Abstract:[Objective] The study analyzed soil erosion in different stages during the construction of Three Gorges Project in order to give support to decrease soil erosion and to improve land-use plan.[Methods] Wanzhou District of Chongqing City was taken as research region, the original observed data, revised universal soil loss equation(RUSLE) and GIS method were applied to investigate the dynamic changes of soil erosion.[Results] The result showed that from year 2000 to 2012, soil erosion intensity decline first and reached the lowest in 2007, then rose slightly. Severe erosive area decreased by 34.24%, and mild erosive area increased by 7.66%. The spatial distribution of soil erosion grade variation was similar to that of actual soil erosion during the study period. Soil erosion grade variation also had the same distribution characteristics in different period. The most active change of erosive grade concentrated in the area between Tiefeng mountain and Fangdou mountain. The southeast part of the research area had low activity in grade change. Transfer matrix of soil erosion intensity showed that soil erosion intensity declined from 2000 to 2012. From 2000 to 2007, about 76.56% of the research area stayed at its original level; 22.78% of the area downgraded gradually. The second stage, from 2007 to 2012, trend of change in erosion intensity was stable, merely 9.77% of the area transformed to higher level.[Conclusion] In 2000-2012, the soil erosion of the surface at Wanzhou District was gradually, and the soil erosion decreased obviously, but after 2007, the erosion situation rebounded, and the erosion situation in some areas was still serious. There is still a strong need for adopting soil erosion control measures, for improving land use measures, and reducing erosion and raising the level of soil conservation.

Abstract:[Objective] The responses of natural and artificial grassland to different types of erosive rainfall in loess hilly region of Western China were researched to provide guidance for vegetation construction and soil erosion control in this area.[Methods] Based on the data measured in 2007-2015 from runoff plots located in Anjiagou catchment, Dingxi City, we analyzed the influences of erosive rainfall on the erosions on 20° slopes of artificial grassland and natural grassland.[Results] In the study area, the erosive rainfall mainly occurs from May to September, and is greater in July and August, and correspondingly the amount of erosion caused by it is more than 70% of the annual erosion. Erosions observed on the two different types of grassland were both finely correlated with PI₁₀. The erosive rainfall mainly refers to moderate rain and heavy rain, the amount of erosion caused by the two intensity rainfalls accounts for about 86% of the annual erosion. The erosion amounts observed in artificial and natural grassland caused by moderate & high intensity rainfalls were 90.8% and 91.2% of total erosion amount, respectively. The amount of soil erosion can well expressed by power function with PI₁₀, PI₃₀ as independent variables. Rainfall with 300 MJ·mm/(hm²·h) or greater erosivity caused the largest proportional soil erosion, for artificial and natural grasslands, the proportion was 32.3% and 33.4%, respectively; rainfall with erosivity of 50~100 MJ·mm/(hm²·h) was most frequent, the erosion amount proportions were 26.0% and 29.1% of the total observed erosions, respectively.[Conclusion] The lower amount criteria of erosive rainfall for artificial grassland(coverage of 75%~82%) and natural grassland(coverage of more than 80%) were 11.3 mm and 11.9 mm, respectively; and the maximum I₁₀ were 10.4 mm/h and 11.7 mm/h, respectively. The natural grassland has better effect of soil and water conservation than artificial grassland has.

Abstract:[Objective] Studying the transpiration and its influencing factors of four typical plants communities (Saccharum officinarum, Miscanthus floridulus, Cipadessa cinerascens and Cyclobalanopsis glauca) in karst peak cluster depression areas of Guangxi Zhuang Autonomous Region to provide scientific basis for the research on regional vegetation ecological water demand.[Methods] Field measurements of transpiration rate(T_r), leaf area index(LAI), and related environmental factors in different seasons were conducted from April 2015 to January 2016.[Results] There was an extremely significant difference(p<0.01) between plants transpiration rates in summer and in other three seasons. The seasonal change of transpiration rates of Saccharum officinarum, Miscanthus floridulus, Cipadessa cinerascens and Cyclobalanopsis glauca were 96.55~197.42, 95.26~169.13, 97.20~239.11 and 81.65~124.42 g/(m²·h), respectively. An extremely significant and positive correlation(p<0.01) or a significant positive correlation(p<0.05) was found between transpiration rate and air temperature for the four typical plants, and extremely significant or significant correlation significant correlation with soil water content(SWC), LAI, soil bulk(ρ_b), and air relative humidity(R_H). Air temperature(T_a) and soil water content(SWC) were the key variables for transpiration in Saccharum officinarum; Air temperature was the key variables for Miscanthus floridulus; In the case of Cipadessa cinerascens, soil water content and soil capacity were the main influence factors on transpiration; Leaf area index, soil water content and air temperature were the main influence factors on transpiration for Cyclobalanopsis glauca.[Conclusion] The differences between transpiration rates of different plant com-munities existed and all of them showed seasonal variation trends. The effects of environmental factors on transpirations of the 4 typical plants were different, which can be artificially induced to regulate the ecological water demand of vegetation.

Abstract:[Objective] The effects of freezing and thawing Cycles on nitrogen in fieldspathic sandstone and sand compound soil were examined in Yulin area of Northern Shaanxi Province, which was expected to improve soil fertility in Mu Us sandy land.[Methods] This paper studied the response of nitrogen mineralization processes in different mixed proportions of fieldspathic sandstone and sand compound soil to freezing and thawing by indoor culture experiment feature.[Results] The alternation of freezing and thawing had a signi-ficant effect on the mineralization of soil nitrogen, and the contents of nitrate nitrogen and ammonium nitrogen in three proportions of soils increased rapidly during the first cycle of freezing and thawing. After 2 cycles of freezing and thawing, the contents of nitrate and ammonium in compound soil decreased. In the period of 5 cycles of freezing and thawing, the contents of nitrate nitrogen and ammonium nitrogen in compound soil all began to show stable increasing trend. After 10 cycles of freezing and thawing, the contents of ammonium nitrogen in 1:1, 1:2 and 1:5 compound soil increased by 10%, 49% and 11% respectively, and the contents of nitrate nitrogen increased by 14%, 39% and 34%%. Especially, nitrate nitrogen and ammonium nitrogen contents the 1:2 compound soil were promoted significantly against the ones of 1:1, 1:5 compound soils, it performed better in nitrogen conservation.[Conclusion] Freezing and thawing cycles promoted the mineralization of soil organic nitrogen, which was beneficial to the accumulation of nitrate nitrogen and ammonium nitrogen in soil, which can provide sufficient nitrogen for the growth of crops in early spring.

Abstract:[Objective] The effects of grass coverage on the regulation of soil erosion and nutrient loss were investigated to provide ways for the treatment of soil erosion on loess slope.[Methods] The data of runoff and sediment were collected under simulated rainfall experiments. Statistical analysis was used to investigate the processes of runoff, sediment and nutrient loss in the loess slope with different grass coverage. Different percentage and pattern of grass coverage were selected to analyze the regulation of runoff, sediment and nutrient loss.[Results] With the increase of rainfall duration, the runoff increased correspondingly. However, sediment, runoff total phosphorus and sediment available phosphorus fluctuated. As compared with the ones on bare slope, the quantity of runoff total phosphorus on the slopes with 25%, 50% and 75% coverages were reduced 66%, 85%, 80%; sediment available phosphorus loss on those slopes were reduced 62%, 47%, 21%, respectively. The effects of grass pattern on the regulation of runoff, sediment and nutrient loss ranked as sediment > runoff > sediment available phosphorus > runoff phosphorus.[Conclusion] The regulatory effects of grass coverage on sediment available phosphorus was better than that on runoff total phosphorus. The regulatory effects of grass pattern on sediment and sediment available phosphorus were better than the ones on runoff and runoff total phosphorus.

Abstract:[Objective] Effects of rainfall on runoff and sediment yield and the quantitative relationships were studied in small watershed of red soil region in South China, in order to provide references for controlling soil erosion and optimizing the use of water and soil resources in this region.[Methods] Based on the three years' observations of natural rainfall events of Wubeihe watershed in Wuhua County of Guangdong Province and Zhuxihe watershed in Changting County of Fujian Province in south red soil region,the methods of regression analysis and path analysis and so on were used to study the effects of single rainfall on runoff and sediments. Meantime, the calculation models were built to study the relationship between rainfall and runoff sediment.[Results] ① The results from the methods of regression analysis and path analysis were essentially in agreement:the main rainfall influence factors of runoff were rainfall, duration, 30-minute maximum rainfall intensity(I₃₀) and the interaction of rainfall and duration. The main rainfall influence factors of sediment yield modulus were rainfall, raininess, 30-minute maximum rainfall intensity I₃₀, rainfall erosivity and the interaction of rainfall and raininess. ② Multivariate linear regression model could accurately reflect the dynamic relationship between rainfall and runoff sediment in the two small watersheds. ③ The model was validated by randomly selected data using Excel, including 25 sets of data in Wubeihe watershed and 23 sets of data in Zhuxihe watershed. The results showed that the correlation between calculated runoff sediment values and the measured data was very significant(p < 0.05), especially for Wubeihe watershed, the correlation coefficient was as high as 0.950.[Conclusion] The multiple linear regression model were the best model for describing the quantitative effects of main rainfall-related factors on runoff and sediment both in Wubeihe watershed and Zhuxihe watershed.

Abstract:[Objective] Investigation of the possible effects of salinization on soil acidity could provide some evidence for understanding the acidification process of protected cultivation soil.[Methods] Three types of surface soils and soil profiles with different acidification characteristics were collected from the protected cultivation farmland, open cultivation farmland and natural acid land. The soils were used for studying the differences in relations among active acid, potential acid and base saturation, and the effects of salt accumulation on soil acidity by means of chemical analysis and simulation tests of fertilizer salt addition and salt leaching.[Results] There was some difference in acidity between the protected soils and natural acidic soils. The acid in the protected cultivation farmland was human input, which was different from natural acid soils. Soil acidification of the protected soils mainly occurred in the surface layer, and decreased from the top to the bottom. Under the condition of the same exchangeable acid content, the pH value of the soils from the protected cultivation farmland was the lowest, followed by open cultivation farmland, while the pH value of natural acid soils was relatively high. At the same soil pH values, base saturation of natural acidic soils was significantly lower than those of the protected cultivation farmland and the open cultivation farmland, and base saturation of soils from the protected cultivation farmland was higher than that of open cultivation farmland. The proportion of active acid in the exchangeable acid of the protected cultivation soils was higher than that of the natural acid soil. Increasing the accumulation of soil salt can decrease soil pH value. Salt leaching process of the protected cultivation soils reduced soil salinity, and it was also accompanied by a decrease in soil active acid and an increase in soil pH value.[Conclusion] The study suggested that the accumulation of salts in soil can enhance the transformation of potential acid to active acid. High amount of application of chemical fertilizer not only can promote the decrease of pH value of soil directly through the input of acidic material, but also can further reduce the pH value of the soil to a certain extent as a result of salt accumulation.

Abstract:[Objective] To evaluate and analyze the fluorine pollution degree and its spatial distribution characteristics of river water and sediment in the main and tributary channels of Yongqiangtang River and Zhongheng River that lie in Longwan industrial area in Wenzhou City, Zhejiang Province and to locate the serious water fluoride pollution river channel and pollution source, in order to provide scientific basis for the treatment of river water fluoride pollution.[Methods] On the basis of field sampling, ion selective electrode method, single factor pollution index method and correlation statistics method were used to measure the fluorine content, to evaluate the fluoride pollution degree, and to discuss the fluoride pollution sources.[Results] The exceeding standard rates of water fluorine content of sampling section on the main and tributary channels of Yongqiangtang River and Zhongheng River were 96% and 83.3%. The proportion of sampling sections on the main, east and west tributary channels of middle reaches of Yongqiangtang River, was 60%, 85.7% and 80%, where the water fluoride pollution grades were evaluated as moderate and severe. The sampled section ratios that were determined as severe on the main and east tributary channel of Zhongheng River in industrial area were 80% and 75%. The sediment fluoride pollution grades of Yongqiangtang River and Zhongheng River were mild and less than mild. Water fluorine content and the number of stainless steel enterprises were closely correlated and about 71.4% of the sampled section ratios had their correlations over 0.9.[Conclusion] The treatment of fluoride-polluted industrial wastewater should be focused, the river water fluoride pollution remediation on the tributary channels of middle reaches of Yongqiangtang River, the main and east tributary channels of Zhongheng River in the industrial area should be carried out. On that precondition, the water environmental quality might be improved effectively.

Abstract:[Objective] In this study, areas of severe burned larix gmelinii forests have experienced different regenerate years. The purpose was to provide a basis for exploring the forest ecosystem restoration and reconstruction.[Methods] The natural regeneration conditions, community structure characteristics, species composition, community biodiversity were observed.[Results] The results showed that:The alpha diversity index of each community layer in different regenerate years showed a rank of herb layer > shrub layer > tree layer. The total number of species had a trend of gradual increase along regeneration. This trend was mainly appeared in herb and shrub layers. The number of species in the herbaceous layer was lower than that of the control plot, except for that in 1996(1996 evere burned, S represents severe burned), while the number of species in the shrub layer were larger than the control plots, except for that in 2003S.[Conclusion] In general, severe fire interference is conducive to the vegetation regeneration and succession.

Abstract:[Objective] Studying the effect of plantation density on understory plant diversity of Haloxylon persicum, to give support for ecological function and technical management of Haloxylon persicum.[Methods] Five types (1 250, 1 111, 1 000, 1 333, 1 667 plants/hm²) of 10~15 years' stand density were selected, and indices of important values, species richness, species diversity index, evenness were calculated to study the relationship between stand density and plant diversity of Haloxylon ammodendron plantation in Minqin County, Gansu Province.[Results] ① There were 16 vascular plants in 15 families and 9 genera of the under-growths in Haloxylon ammodendron forest. Among them, there were 6 families, 6 genera and 6 species in shrub layer, and 4 families, 7 genera and 10 species in herb layer. ② The dominant species of shrub layer changed obviously with the variation of plantation density, while the dominant species of herb layer were hardly influenced by density. ③ Plant diversity of understory vegetation responded non-linearly to stand density. As stand density increased, plants diversity increased initially and decreased laterally. ④ Comprehensive evaluation showed, when density arrived at 1 250 plants/hm², the understory plant diversity reached the maximum. At that plantation density, the growth and development of understory vegetation performed well.[Conclusion] The response of plant diversity of understory vegetation to stand density was non-linear. When the density arrived at 1 250 plants/hm², the density was more appropriate for the growth and development of understory vegetation.

Abstract:[Objective] This thesis took the marsh in Lesser Khingan Mountains as the object, to research the component of activated carbon in soil after wetland was transformed to farmland, forests. This abandoned farmland, which is of great scientific significance to the further understanding on the dynamic change of activiated carbon in soil and the corresponding effects of global warming mechanism.[Methods] This research selected four different types of land use(natural marsh, drainaged wetlands, abandoned farmland, farmland) as the objects, based on field investigation and indoor analysis, making a comparison of the content changes and proportion relations among soil organic carbon(SOC), dissolved organic carbon(DOC), microbial biomass carbon(MBC), easily oxidized organic carbon(EOC), light fraction organic carbon(LFOC), particulate organic carbon(POC). This research made an analysis of the relationship between active componets of organic carbon in soil with the correlation analysis.[Results] The content of organic carbon decreases with the increasing depth of soil under different land use patterns. In general, on the soil profile, the content of SOC in natural marsh is greater than that in other land use patterns, while the difference among the other three patterns of land use is not significant(p > 0.05). Under the four different land use patterns, the content of activated carbon component all shows a decrease tendency with increasing of soil depth in the vertical distribution. Generally, the contents of activated carbon component in the four different types of land use patterns are natural marsh > drainage wetlands > abandoned farmland > farmland.The correlation between SOC and DOC, MBC, EOC, POC, LFOC in soil is significant(p < 0.05).There is a significant positive correlation between DOC and MBC in soil(p < 0.05).There is rather a significant positive correlation between LFOC and POC in soil(p < 0.05).The correlation between EOC and other activated carbon components is not significant.[Conclusion] There are effects on the component of activated carbon in soil under different patterns of land use in Lesser Khingan Mountains. Therefore, people should rationally develop the marsh in Lesser Khingan Mountains.

Abstract:[Objective] This study aimed to reveal cyanobacterial biomass and community structure within shielding nylon mesh in different shrub roots with different plantation ages and within shielding nylon mesh, and to clarify the colonized states of cyanobacteria in different shrub roots and within nylon mesh.[Methods] Biomass of cyanobacteria were measured by counting and volume conversion with microscope and these cyanobacteria were identified according to their morphology, structure, size and other characteristics with toxomony book "freshwater algae of China" and so on.[Results] Number of cyanobacteria was as the highest as 9.84×10⁸ cell/g in the root of Hedysarum scoparium which was planted in 1956, and were the lowest(3.16×10⁸ cells/g) in the root of Hedysarum scoparium planted in 1981 and in the root of Artemisia ordosic planted in 1987. Average total volume of cyanobacteria was the highest(1.04×10¹³ μm³/g) in the root of Artemisia ordosic planted in 1964, and the lowest(6.00×10¹¹ μm³/g) in the root of Carnage intermedia planted in 1964. The percentage of filamentous cyanobacteria was the highest(98.4%) in the root of Artemisia ordosic planted in 1987, and the lowest(38.75%) within nylon mesh. Totally 25 cyanobacteria, mainly belonging to Chroococcales, Oscillatoriales and Nostocales, were found. Among them, Oscillatoria princeps is the most dominant cyanobacteria, and Nostoc punctiforme, Microchatetenera thuret and Calothrix linearis were recognized.[Conclusion] Cyanobacterial biomass and their diversity of three kinds of shrub roots were found higher, probably their rhizosphere habitats are favorable for cyanobacterial colonization and reproduction.

Abstract:[Objective] The purpose of the study was conducted to clarify the effect of fertilization on cabbage (Brassica oleracea L.) yield and N, P, and K nutrient absorption. We expected to provide scientific basis for fertilization reasonably in Lanzhou City.[Methods] A spring cabbage variety "Zhonggan 21" that is cultivated widely in Gansu Province was used as test material in this experiment. Field fertilization with CK (no fertilizer), PK, NK, NP and NPK treatments was carried out in Lanzhou City, Gansu Province in 2013. Dry matters of the cabbage and contents of N, P₂O₅ and K₂O in it were examined respectively at each growth stage. The influences of different fertilizer combination treatments on N, P₂O₅ and K₂O contents and cabbage yield were analyzed, and the absorption rates of N, P and K at different growing stages were explored.[Results] The accumulated amount of dry matter of cabbage exhibited a "S" shaped line. The biomass was relatively low at seeding stage, and increased rapidly after cabbaged phase, but increased slowly and steadily at maturity stage. Nitrogen fertilizer was found having a great influence on biomass at each stage. Phosphate and potash were found having less influences on it. It proved that different fertilizer treatments significantly affected the contents and absorption rates of N, P₂O₅ and K₂O. The results showed that the rates of absorption of N, P₂O₅ and K₂O gradually increased from seedling stage to maturity stage. It also promoted nutrient content. In particular, the N and P accumulations improved obviously at cabbage phase, but K accumulation appeared a great increase at rosette stage.[Conclusion] Ratios of N, P and K fertilizers could significantly affect cabbage biomass, nutrient content and accumulation, nutrition use efficiency and yield. The most important factor is nitrogen fertilizer, the second one is phosphate, the influence from potash is the lowest.

Abstract:[Objective] Explore the characteristics of soil total organic carbon and heavy fraction organic carbon and their relationship to provide scientific bases for studying the carbon fixation effect and soil stability in Ningxia irrigation zone.[Methods] Taking Ningxia irrigation zone as the study area, the contents of total and heavy fraction organic carbon of 5 different types of soil were measured.[Results] Soil type is the main factor for change of soil organic carbon in the Ningxia irrigation zone. After different durations of irrigation and cultivation, total and heavy fraction organic carbon of irrigated soil were both increased. As compared with the non-irrigation and non-cultivation soil, the average increments were 2.27 and 2.02 g/kg, respectively. The increments decreased with the increase of soil depth, but the amplitudes differed among different soil types. There existed significant correlation between fraction organic carbon and total organic carbon.[Conclusion] Heavy fraction organic carbon is an important part of total organic carbon, its correlation with total organic carbon increase with the increase of soil depth. Irrigation and cultivation activities and irrigation time have influence on the soil organic carbon. Studying the fraction organic carbon can better understand soil carbon and soil stability.

Abstract:[Objective] Studying of dynamic characteristics of soil water in the gully region of Loess Plateau is very important to provide supports for the constructions of forest, ecological restoration and management of Platycladus orientalis.[Methods] Sites of 5, 25 and 35 a Platycladus orientalis in typical small basin(Nanxiaohegou basin) in the gully region of Loess Plateau were selected, where the soil moistures in growing season were observed with drying method. On the basis of this, the spatial and temporal distributions of soil moisture in different layers and the desiccation characteristics of each layer were analyzed.[Results] ① The rainfall recharged depth on soil moisture of the Platycladus orientalis concentrated in 0-40 cm while the effect of Platycladus orientalis' roots on soil moisture concentrated in 40-100 cm. ② The temporal variation of 0-100 cm soil moisture during growth season can be divided into recovery period(May) and depletion period(Jun. to Sept.). In the recovery period, the age of the Platycladus orientalis had little effect on soil water distribution. The water storages of 5 a, 25 a and 35 a Platycladus orientalis in 0-100 cm varied between 230.3~304.2 mm, 177.7~249.7 mm and 202.2~283.6 mm, respectively. In the depletion period, the soil moistures of 10-40 cm in different sites ranked:5 a > 35 a > 25 a; while in 60-100 cm, the rank was 5 a > 25 a > 35 a. The 3 sites' water storages of 0-100 cm varied between 131.2~207.2 mm,123.4~220.8 mm and 109.6~204.7 mm, respectively. ③ In the recovery period, there was little difference for the SDIs among different soil layers; while the SDIs in the active layer and transition layer of 25 a and 35 a sites increased with the increase of depth. For root affected layer, its value was relatively stable. In the depletion period, SDI value of the Platycladus orientalis was smaller in the active layer and increased with the increase of depth in the transition layer. For the root layer, the value was relatively stable.[Conclusion] As compared with it in the recovery period, the change degree of soil moisture increased significantly in the depletion period, and the absorption capacity of root increased in older Platycladus orientalis site.

Abstract:[Objective] Exploring the effect of chicken manure co-applied with urea on rhizospheric characteristics and yield, quality of Lablab purpureus, in order to provide theoretical basis for the improvement of quality management in farmland soil and for fertilization optimization of Lablab purpureus plantation.[Methods] A field experiment including four treatments, i. e., CK (neither urea nor chicken manure was applied), CF (100% of nitrogen was provided by urea), CM (100% of nitrogen was provided by chicken manure), and CM+CF (50% and 50% of nitrogen was provided by chicken manure and urea, respectively) was performed. The present study was conducted to determine the effects of different treatments on root exudates contents, microbial population, microbial diversity index in rhizosphere and the yield, quality of Lablab purpureus.[Results] In comparison to CF treatment, CM+CF treatment significantly increased the contents of total amino acid, total organic acid and total sugar in root exudates, showing 61.91%, 43.03% and 31.18% increases, respectively. The populations of bacteria and actinomycetes and contents of microbial biomass carbon and microbial biomass nitrogen were obviously increased by the use of CM+CF treatment. In the meantime, the microbial diversity index was the highest in CM+CF treatment, which had the same variation tendency as total microbial population. However, the microbial diversity indices and microbial population had different variation tendency between CF and CK treatments. Additionally, the CM+CF treatment could significantly increase the yield and improve the quality of Lablab purpureus, indicative of 65.20%, 28.15% and 8.24% increases in yield as compared with the treatments of CK, CF and CM+CF, respectively. Furthermore, the contents of V_c, soluble sugar and free amino acid in legume increased by 45.55%, 36.35% and 43.23% by the use of CM+CF treatment as compared to CF treatment, respectively. However, less effect on rhizosphere and yield, quality of Lablab purpureus in CM treatment was observed in comparison with CM+CF treatment.[Conclusion] As a result, chicken manure co-applied with urea was beneficial on the increases of root exudates, microbial populations and microbial diversity index in rhizosphere and the enhancement of soil nutrient-supply capacity as well as the growth of high-yield and quality Lablab purpureus.

Abstract:[Objective] Revealing the soil moisture characteristics and its response to land use change on Luochuan loess tableland, to provide scientific bases for optimizing land use structure and soil water management on the Loess Plateau.[Methods] Moisture contents in 0-10 m soil profiles under farmland, grassland, apple orchards with different ages (8, 11, 13, 15, 24, 28, and 30 years old) were measured, respectively. Then this paper contrasted and analyzed the characteristics of soil moisture content, soil moisture storage and the desiccation of deep soil layer in various sampling sites.[Results] ① The average soil water contents of different land use types in 0-10 m layer have an order as grassland > farmland≈8-year-old apple orchard > 13-year-old apple orchard≈15-year-old apple orchard > 24-year-old apple orchard≈30-year-old apple orchard > 28-year-old apple orchard. Soil moisture decreased with the increase of soil depth under apple orchard with apple trees older than 24 years, while it increased with the increase of depth in other sampling sites. ② Compared with farmland, the decrease magnitudes of soil moisture within 4-10 m layer were greater than those in 0-4 m layer under apple orchards, and the differences between the two layers got increasing in older apple orchard. ③ The transformation of farmland and grassland into apple orchard can cause soil water storage gradually decreasing and hence worsen water deficit, which might account for 12%~46% of the field capacity. ④ 24-year, 28-year and 30-year orchards caused mild or moderate desiccation with different thickness.[Conclusion] After farmlands and grasslands were turned into apple orchards, the soil water deficit appeared to some degree, and resulted in different thickness of dry layer.

Abstract:[Objective] The objective of this article was to research the effects of standing condition with respect to slope position on some physiological indexes of Reaumuria soongorica, to provide theoretical basis for the restoration and reconstruction of Reaumuria soongorica in arid and semi arid area.[Methods] The study selected Reaumuria soongorica under natural conditions as experimental material, and some physiological indexes of Reaumuria soongorica grew on different slopes were measured by field and laboratory test.[Results] In the upward of slope position, physiological indexes in Reaumuria soongorica leaves changed as followed:① The chlorophyll (a,b,c) contents of Reaumuria soongorica leaves decreased. ② The proline and soluble sugar contents increased, while soluble protein content firstly decreased then increased. ③ The activity of SOD increased firstly and then decreased; the activity of CAT was on the contrary; and the activity of POD and MDA content showed gradually decreasing trends. ④ Nitrate reductase activity increased gradually with the increase of slope positions; while the content of free amino acids increased gradually.[Conclusion] When growing on different slope positions, Reaumuria soongorica adapt to the habitat change mainly by regulating chlorophyll content, SOD, CAT and POD.

Abstract:[Object] In order to improve the detection efficiency of soil and water conservation of the development and construction project, roundly reflecting the soil erosion state and soil and water conservation during construction in real time.[Methods] Based on a lot of practical work of soil and water conservation monitoring, combined with the latest regulation of soil and water conservation monitoring issued by the Ministry of Water Resources, relied on the development of the current aerial remote sensing and unmanned aerial vehicle(UAV) image technologies.[Results] According to the functional requirement analysis of the management system for development and construction project, a soil and water conservation monitoring information management system including data collection, data and information base, application system level, function layer and infrastructure layer was established, and the schematic design were carried out for six sub-systems.[Conclusion] The information management system of soil and water conservation monitoring is reasonable, which can improve monitoring accuracy, ensure the scientificity and accuracy of monitoring data, and provide reference for detailed design in the next step.

Abstract:[Objective] Settlement places, including the urban and village areas, are the central areas of human activities. And they are also the hot and difficult spots for the precise interpretation of remote sensing. In order to extract settlement place in hilly area completely, this paper proposed a new method(SF) that can extract target information from the cooperation of multispectral image and panchromatic image.[Methods] The results had been analyzed comprehensively using GF1 image to extract settlement place in Henshan District Yuling City, Shaanxi Province automatically.[Results] The result showed that the extraction accuracy of SF was improved by 19.56% in comparison with the normal method that extracts target information from fusion data only(F); the number of incorrect pixels was decreased by 39.34%, and the missed pixel's number was reduced by 5.34%.[Conclusion] It can be seen that, SF method not only can effectively improve the extraction accuracy of settlement in hilly region, but also can save post-processing work for the reason that the wrong extraction has been reduced significantly. At the same time, it is also a good reference for the extraction of other land-use type.

Abstract:[Objective] 5 typical side slope plant communities that had been revegetated for 8 years on a section of Daguang highway, that is Fugou-Xiangcheng highway (abbreviated as Fuxiang highway), were selected as research objects. Their stability were measured to provide theoretical foundation for the sustainable landscape construction.[Methods] The data of vegetation community and soil were surveyed and measured. 15 factors of 4 indices involved plant community stability, including species diversity, communities biomass, soil moisture and soil nutrient were used to evaluate the community stability with subordination function method.[Results] Lolium perenne + Trifoliumrepens Linn + Melia azedarach vegetation community had the highest scores of species diversity index, biomass of vegetation communities index and soil moisture index, while the Bidens pilosa + Lolium perenne vegetation community had the highest soil nutrient index. The rank of the 5 typical vegetation communities was Lolium perenne + Trifoliumrepens Linn vegetation community + Melia azedarach vegetation community > Bidens pilosa + Lolium perenne vegetation community > Lolium perenne + Medicago sativa vegetation community > Bidens pilosa + Lolium perenne + Medicago sativa vegetation community > Euonymus fortune vegetation community.[Conclusion] Based on the stability analysis of these vegetation communities, it was concluded that Melia azedarach, Lolium perenne, Trifolium repens and Medicago sativa were the first selected plants for the sustainable landscape in Fuxiang highway. It is better to enrich the vegetation community layers and plant furnishing mode, such as Melia azedarach/Broussonetia papyrifera/Ailanthus altissima/Robinia pseudoacacia + Lolium perenne + Medicago sativa, Melia azedarach/Broussonetia papyrifera/Ailanthus altissima/Robinia pseudoacacia + Amorpha fruticosa + Trifolium repens + Lolium perenne, Melia azedarach/Broussonetia papyrifera/Ailanthus altissima/Robinia pseudoacacia + Amorpha fruticosa + Medicago sativa + Lolium perenne.

Abstract:[Objective] This study aimed to explore the regulating effects of different slope land use patterns and tillage methods on soil moisture and soil & water loss in karst area of Central Guizhou Province, and to provide references for soil & water conservation on karst hillslope.[Methods] Yangjichong small watershed in Longli County, Longchang small watershed in Xiuwen County were took as the research areas, and the soil moisture, runoff and soil erosion were observed by using runoff plot method.[Results] The soil moistures among forestland, abandoned land and farmland were not significantly different(p > 0.05), though soil erosion was significantly different(p < 0.05). The effects on runoff among forestland, abandoned land and farmland were relatively complicated:runoff on abandoned land was significantly lower than the ones on forestland(p < 0.05); while there were no significant differences between forestland and farmland, and between abandoned land and farmland(p > 0.05). The study results of 2 typical tillage methods on soil moisture and soil & water loss indicated that the regulating effects of vegetable planted(spring cabbage) were better than the one of corn planted(monocrop), however, there were no significant differences between these 2 tillage methods on soil moisture and soil & water loss(p > 0.05).[Conclusion] Among the 3 different land use patterns, abandoned land had significant effect on soil and water conservation as compared to the ones of forestland and farmland in karst area of central Guizhou Province, and there was no significant difference between vegetable planted and planted corn.

Abstract:[Objective] The study was aimed to conduct a suitability evaluation of soil and water conservation measures for real-estate projects, which was expected to provide reference for water and soil conservation schemes and the practice in real-estate projects.[Methods] This paper explored the characteristics of soil and water loss of four different types(for residence, commerce, industry, health care and education) real-estate projects in the plain area of Beijing City, and adopted AHP(Analytic Hierarchy Process) to conduct a suitability evaluation of the soil and water conservation measures of various real-estate projects.[Results] Afforestation and beautification, grass brick greening and temporary covering were perfectly suitable for real-estate projects, while seepage well and permeable concrete pavement were not applicable.[Conclusion] Therefore, considering the optimization of soil and water conservation and based on the suitability evaluation results of soil and water conservation measures of real-estate projects, a variety of extremely or moderately suitable soil and water conservation measures should be preferred.

Abstract:[Objective] Simulating the land use change and evaluating the landscape ecological risk of Haitan Island, to provide basis for land use planning and policy development.[Methods] Under the background of planning and constructing in Pingtan County Experimental Area in Fujian Province, this study combined the model of Markov model and the CLUE-S model to simulate spatial distribution pattern of land use in 2021, under the scenarios of either spontaneously developing pattern or rapid urbanization development. The possible evolved landscape patterns under different development scenarios were predicted by landscape index and landscape ecological risk index.[Results] ① The forecast results of 2021 are compared to the land use situation in 2013. The areas of forest, shrub, wetland, farmland decreased by 9.58%,5.53%,2.33%,8.82%, respectively under the scenario of spontaneous development mode; while, these items decreased by 12.86%,6.16%,2.40%,11.67% in the rapid urbanization development scenario. Construction land areas increased by 24.56% and 31.79% in scenarios of spontaneous development and rapid urban development. ② Haitan island landscape patch fragmentation will becoming increasingly serious. The numbers of plaques in forests, shrubs, wetlands, croplands, construction sites and unused land increased differently; the construction land will on the rise but the unused land might change little. ③ The landscape ecological risk indexes were 0.334, 0.337, 0.351 in 2013 and under different development models in 2021.[Conclusion] The whole landscape of Haitan Island tends to be broken and discretized. Landscape ecological risk index is on the rise and the degree of fragmentation of landscape patches is becoming more and more serious.

Abstract:[Objective] This paper studied the infiltration process and infiltration parameters of the Dagu River aeration zones in the seasonal river, and established a suitable model for describing the seasonal river infiltration.[Methods] Based on the experimental data of vertical infiltration of 3 representative rivers on the upper, middle and lower reaches of Dagu River, Horton model, Kostiakov model and Philip model were fitted by Matlab software, the infiltration parameters were obtained, and the suitability of the infiltration model was evaluated.[Results] ① In the upper, middle and lower reaches, with the successive decreases of sand porosity, particle size, permeability coefficient, dry bulk density increased correspondingly, and the steady infiltration rate decreased, with rates of 0.006 6, 0.004 1, 0.002 5 cm/s. ② The Isqcurvefit function in Matlab software was applied to obtain infiltration parameters of infiltration model. ③ The Horton model had the highest fitting coefficients for the infiltration process of the upper, middle and lower reaches of the river bed.[Conclusion] The Horton model performed the best in the simulation of infiltration process, and the model parameters have virtual physical meaning, and can be used to describe the infiltration process of seasonal river bed.

Abstract:[Objective] In order to provide reliable theoretical foundation for the determination of reasonable working parameters for the machine of paving straw-checker sand barriers, the feasibility of inserting straws with Discrete Element Method (DEM) was investigated, and the relationship between the resistance of inserting straw and the speed of the disk blade was analyzed qualitatively.[Methods] A numerical model was built based on DEM for the complex system of sand particles, straws and disk blade, and the dynamic process of disk blade inserting straw was simulated with DEM. Besides, the influence factors on inserting resistance were discussed, such as inserting and moving velocities of disk and distance between straws.[Results] The inserting resistance of disk blade increases with the decrease of the distance between straws and the increase of horizontally moving velocity and vertical inserting velocity.[Conclusion] DEM can be applied to numerically study of straw-checkerboard paving on the surface of sand.

Abstract:[Objective] Using Longdongshui landslide as a case, this article analyzed the genesis mechanism of this kind of landslide from the aspects of hydrostatic pressure and sliding belt softening, and aimed to provide theoretical basis for further identification and research of this kind of landslide.[Methods] Through detailed field geological survey, remote sensing camera, engineering geological mapping and analysis of discrete element numerical simulation, the characteristics of deformation and failure of the landslide were assessed, and the mechanism of the disaster was explored.[Results] The rolling syncline shape by geological structure formed the rudiment of the landslide; soft and hard interbedding structure provided the material basis for the landslide; three directional emptiness for landform condition provided space for the motion and deformation space; unloading and tectonic fracture provided precedent infiltration channel for surface water; water softening effect of the potential sliding surface by groundwater and static water pressure were the triggering factors of landslide.[Conclusion] The movement of the sliding body is not only the effect of the hydrostatic pressure of the posterior margin, but also is the physical softening of the groundwater. It is the joint effect of the hydrostatic pressure and the physical softening of the trailing edge fracture that will result to, and furthermore, the trailing edge hydrostatic pressure plays an accelerated role in the deformation and sliding of the slope.

Abstract:[Objective] Exploring the influence of imogolite on the dispersion and coagulation characteristics of montmorillonite and kaolinite, to provide a theoretical basis for soil and water conservation and environmental protection work.[Methods] Montmorillonite and kaolinite solutions were respectively mixed with a certain proportion of imogolite solution. After that, turbidimetric method and ion exchange method were used for the measurements of the dispersion of clay and charge characteristics of clay; and electronic microscope was used to observe the effect of imogolite on the dispersion & flocculation characteristics of montmorillonite and kaolinite.[Results] The mixture kept coagulated in any pH value when imogolite and montmorillonite was mixed in a of proportion of 1:1; solution of Kaolin without iron removal processing was observed agglomerated when pH value was below 5.9 but dispersed when pH value was more than 6.0. The aggregation characteristics of kaolin without iron removal processing reversed when about 5% of imogolite was added.[Conclusion] From the microscopic point of view, imogolite mixed solution was in coagulated state whether in acidic or alkaline condition. When the solution of imogolite was acidic, it agglomerated because of the gravitational coagulation between variable charge of itself and the permanent charge of clay crystallinity minerals; when the solution was alkalinity, the surface of imogolite became neutral and agglomerated.

Abstract:[Objective] To provide a reference for the flood-control safety of the loess plateau check dam system, a BP neural network combination model was tried to apply for predicting runoff from a storm-flood event.[Methods] The BP neural network(BPNN) combination model(BPNNC) was constructed on the base of multiple linear regression model(MLR) and detrended cross-correlation analysis(DCCA). Its output was compared with those from other three single models(MLR, BP neural network and DCCA) by the model evaluation indexes of mean square error(MSE), mean absolute error(MAE), mean absolute percentage error(MAPE), and deterministic coefficient(DC).[Results] The four values of MSE, MAE, MAPE and DC from BP neural network combination model were 2.144, 5.453, 0.074 and 0.988, respectively, which were better than the ones of the single models. The order of model precisions from high to low was BP neural network combination model, BP neural network model, multiple linear regression model and detrended cross-correlation analysis, successively.[Conclusion] The BP neural network combination model is more stable as compared with the single models, which can be used to predict the runoff from a storm-flood event.

Abstract:[Objective] Conducting a spatial analysis on wetlands ecosystem restoration along Yangtze River in Anqing City, Anhui Province, in order to provide scientific basis for improving the wetland ecological environment. Wetland restoration is critical to manage these conditions.[Methods] In this study, hydrological regulation and habitat suitability, as the most important functions of wetland, were selected to identify suitable wetland restoration sites. Using these two function layers, together with the spatial analysis function of geographic information system(GIS) and remote sensing(RS) image data, we identified and prioritized suitable sites for wetland restoration in the study area. Those areas which have high hydrological regulation and are good or fair habitat suitability for water birds, can support wetland restoration. The potential sites were prioritized in terms of patch size and proximity of natural wetlands and water bodies.[Results] We obtained two priority classes(the high one and a low one) of wetland restoration in a spatial scale. The results of this study showed that the areas with high and low priority classes for wetland restoration are 82 628 and 247 039 hm², respectively, which account for 1.23% and 3.67% of the total study area.[Conclusion] The high-priority class areas would be used for the wetland restoration. Besides the wetland restoration in the northeast region, wetland landscape pattern is also more advantageous for wetland ecological function. It will provide scientific basis for the implementation of northeast region wetland restoration.

Abstract:[Objective] The objective of this paper was to discuss the evaluation method of rural river ecological restoration technology, and to provide theoretical basis for the ecological restoration of rural river.[Methods] Considering economic benefits, social and ecological environmental benefits, the impact of river basic functions, pollution and natural conditions, this paper established an index system of comprehensive assessment on the ecological restoration of rural river by fuzzy analytic hierarchy process(FAHP).[Results] The comprehensive assessment values of four kinds of ecological restoration technologies of Zipeng Town reach of Paihe River in Hefei City were as follows:the evaluation values of phytoremediation, river aeration, constructed wetlands and ecological floating bed were 85.058, 70.255, 73.456 and 68.018 respectively. Phytoremediation was determined to be adopted for the ecological restoration.[Conclusion] The application of ecological restoration technology assessment system established by the FAHP was comprehensive and objective. If combined with the decided selection criteria, it can provide references for the selection of appropriate ecological restoration technology of rural river.

Abstract:[Objective] It is necessary to study farmland meta-ecosystem service value to reflect the region ecosystem safe and farmer livelihood sustainable in arid area.[Methods]This paper calculated farmland meta-ecosystem value and analyzed the influence factors of eight county protection of desertification land perimeter of Hexi Corridor in the arid region by ecological economic method and multiple regression.[Results] The result showed that farmland meta-ecosystem unit area service value increased from 19 966 yuan/hm² to 21 511 yuan/hm², the increment was 1 545 yuan/hm², the annual average growth was 0.58%. Raw material production, waste treatment, soil formation, erosion control and food production were the main increased items. Farmland meta-ecosystem total value increased from 2.94×10⁹ yuan to 4.25×10⁹ yuan,the increment was 1.31×10⁹ yuan, the annual average growth rate was 2.88%. The quantity of basic service value and social security function value had greater increases than environment pollution service value and water consumption function value had, but the increase rates of environment pollution service value and water consumption function value were faster than those of basic service value and social security function value. The changes of farmland meta-ecosystem unit area service value of the eight countries had spatial and type differences, Except of Dunhuang City, farmland meta-ecosystem total service values of seven countries increased. The variation of farmland meta-ecosystem service value in the study area was mainly affected by grass agriculture production, rural per capital income, chemical fertilizer consumption, scale economic crops and grain yield per hectare.[Conclusion] The Reversion of ecological degradation has positive influence on farmland meta-ecosystem value of most country, but environment pollution and water consumption were increasing constantly, for that reason, the vulnerability of land desertification reverse trend is still high.

Abstract:[Objective] To comprehensively evaluate the ecological revetments of rural river,in order to improve the comprehensive level of ecological management of rural rivers in the construction of new countryside.[Methods] Comprehensive evaluation systems of ecological rural river revetments in plains, hills and mountain areas were built from five aspects, namely:cost, construction materials, effects on the function of water conservancy, ecological function and social landscape features. Index weights of ecological rural river revetments in the three areas above mentioned were calculated using analytic hierarchy process and the ecological revetments were evaluated using rank-sum ratio.[Results] Seven kinds of ecological revetments, including ecological stone cage revetment, ecological concrete revetment, plant revetment, timber revetment, rock revetment, ecological brick retaining wall and ecological bag revetment, were chosen to be comprehensively evaluated in three kinds of rural rivers. It was concluded that the ecological rick retaining wall and the plant revetment are suitable for the middle and lower reaches of Shiwuli River, their indexes of WRSR are 0.692 3 and 0.662 2; the ecological brick retaining wall and the ecological concrete revetment are suitable for the Caishi section of Cihu River, their indexes of WRSR are 0.663 5 and 0.659 0; and the ecological concrete revetment and the ecological stone cage revetment are suitable for the upstream of Jiuhua River, their indexes of WRSR are 0.551 6 and 0.537 8.[Conclusion] The result of this evaluation system is reasonable and can be used to improve the construction level of ecological revetments of rural river.

Abstract:[Objective] Exploring the optimization of low-carbon economy oriented land use structure to provide support for government land use planning and adjustment.[Methods] The best land use structure program was carried out by adopting gray multi-objective linear programming method to establish an objective function.[Results] In reference with land use planning scheme, we found that the medium carbon emission scheme in Fuzhou City is the best land use structure program. This medium carbon emission scheme was predicted that can decrease carbon emissions as much as 1.30×10⁷ t, increase economic benefits as high as 7.70×10¹¹ yuan and increase ecological benefits as high as 7.85×10¹⁰ yuan by 2020.[Conclusion] The low-carbon economy oriented land use structure would be in favour of the regional economic benefits and ecological environment improvement, which can reach the carbon reduction target.

Abstract:[Objective] Surveying the treatment status and put forwarding the manage countermeasure of spare earthworks in municipal production and construction projects, to explore suitable management approach and countermeasures for spare earthworks in urban construction projects.[Methods] Taking Beijing City as a case, the paper analyzed current situation and the existing problems of municipal production and construction projects, and then put forward the management countermeasures with reference to native and alien earthwork management experience.[Results] A basic understandings of spare earthwork management and related environmental problems were showed in the paper, including inter-coordination use, placement of spoil ground, earthwork outsourcing processing, residue ground, resource utilization of construction waste, etc. Referring to native and alien earthwork management experience, we put forward several management measures for extra earthwork in production and construction projects in Beijing City, including strengthening the protection and publicity of soil resources, adding earthwork management to the preliminary scheme of the construction project, developing reuse technology of construction waste and river sludge, establishing earthwork information platform, etc.[Conclusion] The current management measures of the production construction project have not met the demand of urban construction and development. Therefore, to improve the utilization efficiency of extra earthwork in urban production and construction projects, the management system of earthwork should be established and improved in the future through the reinforcement of legal protection, capital investment, policy support, technology improvement and information communication.

Abstract:[Objective] Constructing a multiple linear regression model of describing soil chloride ion with high spectral bands as independent variables to get soil salinization information, in order to provide a more effective method for the high precision extraction of salt, and to provide scientific basis for the reconstruction of agricultural ecological environment.[Methods] 93 field soil samples were collected and processed by high ASD spectrometer in Kenli County of Shandong Province on October 5 to 7, 2014. A estimating model was built using multiple regression and principal component analysis method to evaluating the content of chloride ion quickly.[Results] The chloride ion is sensitive in the 749, 830, 987, 1 301, 1 432 and 1 486 nm of spectral bands. An optimum model for predicting chlorine ion content in indoor dried soil was obtained on the basis of soil spectral analysis, this model was verified by Student's t test.[Conclusion] The cations in the soil components of the study area are mainly sodium ions, the anions are mainly chloride ions, and this model makes it possible to obtain soil salinity indirectly.

Abstract:[Objective] Taking Xingyun Lake in Yunnan Province as an example, the lake health evaluation, with basin impact factors were taken account to provide reference and demonstration for the health evaluation of the plateau lakes in Central Yunnan Province.[Methods] Based on the investigation and analysis of the driving factors of the lake condition, considering the influence of the impact factors from the basin scale on the lake environment, the revised evaluation index system of the plateau lake considering the basin impact factors was constructed, and the specific quantitative evaluation and characteristics of recognition of Xingyun Lake health status in Yunnan Province were carried out under the support of remote sensing and GIS technology.[Results] The quantitative values of the evaluation indexes under the 5 criterion layers of the Xingyun Lake that include hydrology and water resources, the physical structure of the lake, the water quality, the biological and social service functions were obtained. The overall health status of the Xingyun Lake belongs to the general level. The main constraints originated from water quality, biological, hydrology and water resources.[Conclusion] The assessment index system and method used in this work overcome the spatial scale restriction that conventionally understand and assess lake degradation problem only from the lake itself and the subsequent insufficient consideration about driving indexes problem. The method and technique applied in the Xingyun Lake health evaluation will give benefit to other plateau lake assessment in Central Yunnan Province.

Abstract:[Objective] The functional characteristics of ecological service and the variation trend of key ecological functional areas(Dujiangyan City) were analyzed and predicted to provide a scientific basis for environmental protection and goal determination of rational urban development for this region.[Methods] Based on the land cover data of three Landsat remote sensing images in 1995, 2007 and 2014, calculation method of ecosystem service value from Costanza and the 2002 edition value equivalent method of proposed by Xie Gaodi in 2002 for regional correction, and combing coefficient of sensitivity, we discussed the changes of Dujiangyan's ecosystem service value from 1995 to 2014. Using the Grey Dynamic Model (1,1), the development trend of ecosystem service value in Dujiangyan City were forecast.[Results] ① In the study area, forest and farmland were two main factors, which accounted for more than 80% of the total area. The land cover changed a lot in 1995-2014, and the ecological land reduced. ② The total value of ecosystem services decreased by 629.46 million yuan during 1995-2014 in Dujiangyan City. Forest was the most valuable ecosystem in the area, which accounted for more than 83% of the total value, followed by farmland, water, grass and unused land. Water conservation and waste gas treatment were two most prominent ecological services, which accounted for more than 56% of the ecosystem services in this area. ③ The GM (1,1) predicted the land cover change and ecosystem services value in the study area from 2021-2035. The results suggested that during this period, ecosystem services value will be slowly increased by 136.6 million yuan in the study area, and the average annual growth rate is 0.17%.[Conclusion] The increase of the traffic mainly caused the reduction of the regional ecosystem service value, leading to the decrease of ecological land area. The increase of those land cover types with high ecological values, such as forest and water is an effective measure to maintain and improve regional ecological functions.

Abstract:[Objective] Studying the spatial-temporal variation and the influencing factors of ecosystem water source supply service in Upper Hanjiang Basin during 2000 and 2010, in order to provide basis for scientific management and policy formulation of regional water resources.[Methods] The water yield module within InVEST model was used to analyze the supply service.[Results] Forestland, wetland and construction land areas increased in the decade, while farmland area decreased. Grassland area remained stable. Annual mean vegetation coverage was in an overall rise with a gradient of 0.005 1/a. Water yields of upper Hanjiang basin in 2000, 2005 and 2010 were 46.70, 52.21 and 47.29 billion cubic meters, respectively.[Conclusion] Spatiotemporal variation of water source supply amount in the study area was a combination result of climate and land use change. Increased precipitation had a positive role in increasing water yield. Change of underlying surface caused by land use change and ecosystem improvement could be the main driving forces of the declined water supply in upper Hanjiang basin.

Abstract:[Objective] The spatio-temporal characteristics of cultivated land resources security in Anhui Province in recent 14 years were illustrated, in order to provide directions for economic development and land resource protection.[Methods] In terms of 27 selected indicators from three aspects as quantitative security, qualitative security and ecological security, an integrated assessment system of cultivated land resources was established.[Results] ① The quantitative and qualitative security of cultivated land resources showed decreasing and increasing trends, respectively. Ecology security remained stable, and the integrated security showed an upward trend. ② The spatial characteristics of quantitative security showed high values in the east and North of Anhui Province and low values in the South of Anhui Province; the values of qualitative security were higher in the middle and south of Anhui Province; moreover, the ecological security in the middle and south regions was lower than that in other areas; the spatial characteristics of integrated security of cultivated land resources was similar to that of quantitative security. The cities with low integrated security levels presented a characteristics of concentration to dispersal, and it was opposite for the high integrated security level cities. ③ The main obstacle factors of quantitative, qualitative and ecological security of cultivated land resources showed an obvious variation features.[Conclusion] The situation of the cultivated land resources security in Anhui Province was still severe. Appropriate method, therefore, should be taken to improve the level of security.

Abstract:[Objective] Bailongjiang Watershed was selected as a case to study the spatiotemporal change of ecological carrying capacity(ECC) and its driving mechanism from the perspective of land use change for the purpose of the ecological environment management and sustainable development of the watershed.[Methods] Based on the theory of ecological footprint, the spatial and temporal changes of the ECC of the watershed during the latest 25 years were analyzed by the remote sensing data and transfer matrix analysis method from 1990 to 2014.[Results] ① On the time scale, the ECC of watershed during the latest 25 years changed with a general trend of "decrease-increase-decrease", but had different trend for different land use type. ② On the spatial scale, the watershed ECC showed an uneven spatial distribution:the area with higher value located in the northwestern and southwestern parts, and the area with low value located in the northeastern parts; the higher of the altitude and gradient, the higher of ECC. ③ From 1990 to 2002, 2002 to 2010 and 2010 to 2014, the change of the watershed ECC varied frequently with apparent transfer, respectively.[Conclusion] The watershed ECC fluctuated increasingly while the ecological quality was improved during the latest 25 a. The spatial pattern of the watershed ECC changed with obvious spatial heterogeneity due to the landform characteristics and land use/cover change, the grain for green project also affected the change of watershed ECC.

Abstract:[Objective] In order to understand the ecological benefits of returning farmland to forest in Baoji City, and to provide reference for related ecological research.[Methods] Based on the area data of returning farmland to forest in Baoji City, Shaanxi Province from 1999 to 2015, this paper computed the ecological benefits arising from the protection of water, conservation of soil, carbon sequestration, purification of the environment, improvement of microclimate and conservation of biological diversity, in reference to the appendix of ecological benefit physical quantity evaluation formula and reference setting for returning farmland to forest project in ecological benefit monitoring and assessment technique and management norm of returning farmland to forest project.And the ecological value of returning farmland to forest project was also calculated using the shadow project and shadow price method in Baoj City.[Results] The total value of forest ecological benefit from 1999 to 2015 in Baoji City was 1.06×10¹⁰ RMB, in which the protection of water resources and carbon sequestration & oxygen production contributed the most, the proportions were 36.8% and 27%. The conservation of biological diversity contributed 22.8% of it; The improvement of the microclimate, soil conservation and environmental purification value contributed 12.2%. 0.8% and 0.4% of it, respectively.[Conclusion] It can be seen that the project of returning farmland to forests plays an important role in water conservation and improvement of the environment in Baoji City. And it is of great significance for the protection of water resources and the improvement of air quality in this area.

Abstract:[Obiective] Effects of stirring soil particle suspension on the analysis of soil texture were researched to provide guidance for the determination of soil mechanical composition accurately.[Methods] The comparison and analysis were carried out under different conditions, such as stirring stroke, stirring number, stirring when soil particle suspension was placed at different time and stirring at different determination time, in the determination of soil mechanical composition by gravimetric method.[Results] The stirring stroke, stirring number and stirring after suspension all had no effect on clay particle content, but had impacts on the silt and sand content. Stirring rod stirred from the liquid level down to the bottom of the precipitation tube was conducive to uniform distribution of particles, determination of the clay, silt and sand content was stable, precision was good. At the condition of the suspension setting time was more than 1 h, measurement of silt and sand content was unstable when it was stirred 30 times. Measurement of silt sand and clay content was stable, precision was good when it was stirred 45 times. The addition of stirring before the second test points had no impact to the results.[Conclusion] The optimized method was helpful to reduce the errorwas accurate and reliable, and suitable for simultaneous detection of multiple samples.

Abstract:[Objective] Evaluating urban land use efficiency and cultivated land use efficiency of Chengdu-Chongqing urban agglomeration, to promote the common development of new urbanization and agricultural modernization.[Methods] Taking Chengdu-Chongqing urban agglomeration as a research object, the paper built up an evaluation system of urban land use efficiency and cultivated land use efficiency. Super SBM model, gravity center model and coupled coordination model were used to analyze the spatial-temporal pattern and coupling coordination degree of the two.[Results] From 2005 to 2014, urban land use efficiency followed a fluctuating ascending trend and the efficiency center of gravity shifted vertically to the south. The cultivated land use efficiency presented a V type as a whole. Gravity center changed greatly in the horizontal direction to the east. The coupling type and coordination degree with respect to the utilization efficiency of coupling coordination of urban land and cultivated land showed a shape like spindle. There was great number of high-coupling & medium coordination cities in the research object. Cities along Nanchong-Luzhou changed greatly in terms of coordination type.[Conclusion] The coupling degree of urban land use efficiency of Chengdu-Chongqing urban agglomeration is relatively high and has a positive development trend.

Abstract:[Objective] The objective of this paper was to evaluate land utilization performance and analyze obstacle factors and to provide scientific basis for the improvement of urban land utilization efficiency and allocation of land resource reasonably.[Methods] An indicator system of land utilization performance evaluation, especially for the northwestern region of China, was set up in consideration of local natural environment characteristics. The system mainly had topics of land utilization structure, land utilization degree and land utilization efficiency. The level of urban land utilization performance and the obstacle factors of land utilization were measured based on the data of Hohhot-Baotou-Ordos from 2004 to 2013 using TOPSIS and the model of land utilization obstacle degree.[Results] Research showed that the performance of land utilization of Hohhot-Baotou-Ordos was ascending differently. The performance of land utilization of Hohhot went steadily up. Baotou was stable and Ordos was slower. The main obstacle factors were land utilization structure and social benefits of land utilization.[Conclusion] The performance was closely related to the amount of endowment resources and policy implementation. This paper advised that cities of Central Inner Mongolia should strengthen the urban public facilities and social benefits, optimize the land use structure, and improve land use intensive degree. Cities in central Inner Mongolia have close economic, trade and social intrinsic ties. Land utilization should be improved based on cities integration to form industrial agglomeration and promote the optimization of land resources as a whole.

Abstract:[Objective] Studying the relationship among slope & aspects, land use change and net primary productivity, so as to provide scientific basis for regional ecological sustainable development.[Methods] We took Baoji City as an example to study the effect of land use change on regional net primary production based on different slopes and aspects with the help of digital elevation model and the Landsat TM images. We used the CASA model to estimate net primary production of Baoji City.[Results] From 2000 to 2010, the change of net primary productivity in Baoji City was concentrated in forest land, cultivated land and grassland, among which forest land had the greatest influence. More than 96% of forest lands remained unchanged in the past ten years, and about 77% of grasslands was transformed into forest lands. The total area of forest lands was 12 239.67 km². The net primary productivity of forest lands in the sloping land was the most significant, with a net increase of 166 668.60 g/(m²·a); and the net primary productivity increment in the semi-shady aspect area was the highest, reaching 182 230.00 g/(m²·a). The influence of cultivated land on the net primary productivity concentrated on the flat land and the gentle slope. The aspect's range is from the sunny aspect to the semi-shady aspect and the highest value was 59 479.5 g/(m²·a) at the sunny slope. The change of grassland was less affected by the aspect condition, so its effect on the net primary productivity was relatively balanced in the slope condition, and the slope distribution was mainly slope and gentle slope.[Conclusion] Overall, the ecosystem of Baoji City keeps a good situation. Moreover, keeping net primary production in sustained growth is very important, and to maintain the sustainable development of ecological environment, we should take better account of Baoji's location and terrain to make good use of the forest land in sloping land and the semi-shady aspect.

Abstract:[Objective] The aim of study was to analyze the effects of forest ecological service value transfer from upstream in Hunhe River basin on water supply in Shenyang City cluster, which might contribute to make forest ecological compensation standard of the river basin.[Methods] From the perspective of forest ecological service transfer, forest ecological service value transfered from upstream were calculated with ArcGIS 9.3 buffer and overlay analysis platform from 2010 to 2014, and then it studies the effects of forest ecological service on water supply in Shenyang City cluster were studied using the path analysis.[Results] Forest ecological service value transfered from the upstream in Hunhe River basin reached 5.647 billion RMB from 2010 to 2014. Forest ecological service of the water conservation and the soil conservation in the upstream had impacted on the water supply in Shenyang City cluster by surface water, groundwater and chemical oxygen demand(COD).[Conclusion] Forest ecological service value transfer in the upstream generates positive externality, which comprehensively influences on the water supply in Shenyang City cluster by direct effect and indirect effect from multiple factors.

Abstract:[Objective] This study conducted rechecked division of key preventing and controlling area of urban-type soil erosion at county-level, to provide support for deep development of the prevent and control methods of soil erosion at county-level.[Methods] According to the key factors such as land use status, soil erosion intensity, vegetation coverage extracted from ArcGIS and eCognition, we explored the soil erosion division with regard to key prevention area and key control area in Xigu District, Lanzhou by combining qualitative and quantitative methods, and top-down and bottom-top methods.[Results] The district has characteristics of small jurisdiction, large population, developed economy, small proportion of the primary industry, land use fragments, serious soil erosion, potential erosive harm and others. We determined the qualitative and quantitative index of the above two areas:two key prevention areas and two key control areas.[Conclusion] ① Our main efforts of soil and water prevention should be pay to the upstream hilly regions to prevent downstream cities from being suffered erosion. ② Forest close and natural revegetation should be taken into effect in the mountains that have abundant rainfall. ③ Farm mechanization should be developed to increase the income of farmers.

Abstract:[Objective] This paper mainly analyzed the effect of water resource supply on land use structure. It might provide the bases for the policies with respect to coordinated utilization of urban land resource and water resource in the Yangtze River delta, and for decision support of water-saving society construction of the 13th Five-Year Plan, as well.[Methods] Based on the theory of structural-functionalism, having the basic functions of urban production, life and public service as core, a mathematical model was built between several pairwise factors, as productive water and productive land, living water and living land, service water and service land in the Yangtze River Delta during 2001-2014.[Results] ① There was a significant positive correlation between the supply of living water and the scale of living land. And a significant positive correlation between the supply of productive water and the scale of production land was also detected. However, the service water had no significant effect on the service land. ② The regression coefficient was 0.339 3 between living water and living land, and was 0.086 7 between productive water and productive land. ③ From the regression coefficient, the influence of water supply on living land was much greater than that on productive land. The effect of water resource supply on land use structure was positively correlated with GDP and urban scale rank. In general, a city with more GDP and larger scale might easily undergone severe feedback from water resource supply.[Conclusion] The influences of water supply on the life land and production land both existed. The influence on the public service land had not yet appeared in the Yangtze River Delta. If water resources are becoming scare, the development and utilization of urban land resources will be directly affected in large city.

Abstract:[Objective] To provide scientific basis for soil and water conservation, the dynamic monitoring and temporal and spatial variations of soil erosion in Fujian Province from 1990 to 2015 were studied.[Methods] Choosing Fujian Province as a study area, combined with GIS and RS technologies, the research was carried out based on USLE model.[Results] ① The soil erosion intensity of Fujian Province was general light. The soil erosion areas were found primarily in the western and southeastern of Fujian Province and less in central and northern parts. As to the spatial variation of soil erosion, a decreasing trend from the southeast coastal area to the northwest inland area was found existed. During the past 25 years, the transfer of soil erosion intensity mainly occurred between the light/moderate erosion and slight erosion. ② From 1990 to 2015, the area of soil erosion reduced by 3 825.55 km² totally, which was mainly covered by light erosion intensity. Especially after 2010, the area of soil erosion showed a faster shrink. Meanwhile, soil erosion in coastal areas got improvement more evidently than the erosion in inland areas.[Conclusion] The improvement of soil erosion in Fujian Province was obvious during the past 25 years, which showed significant benefits in soil erosion control.

Abstract:[Objective] The gray water footprint was considered to evaluate the situation and trend of sustainable utilization of water resources in Jiangsu Province, and to provide scientific basis and policy support to some extent for the determination of reasonable water sustainable utilization strategies, and to give some innovative advices for water resources management.[Methods] The study calculated water footprint and its characteristics in Jiangsu Province from 2005 to 2015 by applying the water footprint theory, and analyzed the situation of sustainable utilization of water resource in terms of water footprint structure, social benefit, economic benefit and ecological security. In addition, GM(1,1) was used to predict the development trend in the next five years.[Results] ① The water footprint of Jiangsu Province showed an inverted U-shaped curve in the study period, got the highest(1.22×10¹⁰ m³) in 2011, and showed a fast declining trend. ② Jiangsu Province can self-supply (average water self-supplication is 88.1%) in supply water resources. It is in a high level of economic and social benefit, but still be in a state of serious water shortage. ③ According to the "Inertia development" situation, the water footprint in 2020 will have a 0.92% decline as compared with that in 2015.[Conclusion] As the strictest water resources control system was applied, water use efficiency has been improved, and the water resources utilization of Jiangsu Province presents a trend of sustainable development.

Abstract:[Objective] The change characteristics of land use pattern in Bayan County, Heilongjiang Province were explored to laid foundation for land use pattern optimization.[Methods] AutoLogistic regression model and spatial statistical analysis method were used.[Results] ① Introducing the spatial autocorrelation factor to construct AutoLogistic regression model is more applicable and reliable than the traditional Logistic model in analyzing the change characteristics of regional land use pattern. ② The land use pattern is closely related to natural and human factors. Elevation, landform, pH value, soil organic matter, distance to town center, distance to waters, distance to roads, location index, centralization degree, land use diversity and land use intensity are the main influencing factors of land use pattern change. ③ The obvious spatial differentiation characteristics of the distribution of different land use types were restricted by influencing factors. The paddy, water and grassland were mainly distributed in the areas of level 1 elevation. The dry land, paddy, garden and construction land were mainly distributed in the 2 and 3 levels of soil organic matter. The dry land, garden and construction land were mainly distributed in the areas of level 1 distances to the town center and the level 4 and 5 land use intensity.[Conclusion] The land use pattern of the study area shows obvious spatial differentiation characteristics under the combined effects of various factors.

Abstract:[Objective] The response of soil water dynamics in Scotch pine sand-fixation forest to rainfall infiltration was analyzed to provide basis for further studying sand soil water management.[Methods] Watchdog soil moisture automatic monitoring system were used to record soil water content of 0-120 cm soil layers in Scotch pine(Pinus sylvestnis) sand-fixation forest in Hunshandake sandland, form June 20 to October 31 year 2014, and form May 1 to September 30 year 2015, respectively. And at the same time, we selected the 3 kinds of rainfall events to study soil moisture content variation with respect to rainfall infiltration under different influence processes in different depth soil layers of Scotch pine sand-fixation forest.[Results] In 19.4 mm rainfall event, it took 4 h for the rainfall infiltration reached to 20 cm soil layers in Scotch pine sand-fixation forest, it took 5 h in moving sanddunes; in 30.2 mm rainfall event, 13 h and 9 h elapsed when the rainfall infiltrations reached to 40 cm soil layers in Scotch pine sand-fixation forest and in moving sanddunes; in 47.1 mm rainfall events, 27 h and 24 h elapsed when the rainfall infiltrations reached to 80 cm soil layers in Scotch pine sand-fixation forest and in moving sanddunes. Depth of rainfall infiltration in Scotch pine sand-fixation forest reached to 80 cm soil layers in 19.4~30.2 mm rainfall events comparatively, depth of rainfall infiltration in moving sanddunes was more than 80 cm soil layers even in 19.4 mm rainfall events, it was more than 120 cm soil layers in 30.2 mm or 47.1 mm rainfall events.[Conclusion] Different rainfall events significantly affected on rainfall infiltration process and depth of rainfall infiltration in Scotch pine forest.

Abstract:[Objective] The study aimed to grasp the coupling coordination relationship between urbanization and ecological environment in the Yangtze River economic belt from 2005 to 2014, and to provide theoretical basis for the overall planning of the healthy development of the whole region.[Methods] Taking the Yangtze River economic belt in nine provinces as the study area, we developed an evaluation system for urbanization and ecological environment coordinated development. Using variation coefficient and coupling measurement model, the paper analyzed the Yangtze River economic belt coupling coordination relationship of urbanization and ecological environment from spatial and temporal aspects.[Results] ① In the aspect of temporal characteristics, the coordinated degree was continuing to rise from 2005 to 2014, and the index of urbanization was faster than the index of ecological environment. ② In the aspect of spatial characteristics, the coordinated degree showed regional differences. And from the perspective of province, the coordinated development level of urbanization and ecological environment has obvious spatial variation, showing the "northeast-southwest" spatial characteristics corresponding to high-low distribuion.[Conclusion] The coordinated development level of urbanization and ecological environment in the Yangtze River economic belt showed a high Northwest-low Southwest spatial pattern, and existed an obvious spatial difference. In the future, we should pay attention to the coordinated development of the whole region.