Abstract:[目的]在泰国北部山区开展实地调查，研究该区土壤侵蚀特征，旨在为泛第三极暖湿区的土壤侵蚀预报和水土流失治理提供依据。[方法]以位于北部山区的清莱府为泰国土壤侵蚀典型区域的代表区域，选取18个调查单元（小流域/矩形区），于2018年11月22-29日调查了该区土壤侵蚀的类型与特征、土地利用类型及其空间分布、植被类型及盖度、耕地状况和作物类型、水土保持措施等。[结果]土壤侵蚀主要发生在道路、田地边坡、坡耕地（尤其是新耕种的坡地）和建设用地边坡，部分林下也可见侵蚀沟发育。未经硬化的土路大多存在不同程度的侵蚀，部分道路形成严重的侵蚀沟。坡耕地的侵蚀在新耕种的田块及其边坡处尤为严重，田块内部主要表现为细沟和浅沟侵蚀，以新近种植的菠萝地最为严重。林下土壤侵蚀主要出现在林下裸露的橡胶纯林内，甚至有浅沟和切沟出现。18个调查单元的平均土壤侵蚀模数介于480.9~3 565.3 t/（km·a）之间，总体平均为1 767.9 t/（km·a）。该区域土壤侵蚀模数及其空间变异的主控因素是地形因子。[结论]泰国北部山区虽有大面积的森林覆盖，但采用的水土保持措施相对简单，对开垦坡地的不合理利用引起了严重的人为加速侵蚀，加之该区地形复杂，导致土壤侵蚀严重威胁生态安全和粮食安全。同时，该区的土壤侵蚀基础观测资料缺乏，迫切需要加强土壤侵蚀的基础研究和基础数据的采集，提升对该区域土壤侵蚀过程与机理的认识，注重水土保持措施的综合运用，同时加强土壤培肥、污染防治和土壤保育等措施，保障泰国农业的可持续健康发展。

Abstract:[Objective] To study the decomposition rate of litter leaf and investigate the relationship between litter decomposition rate and their initial quality in order to provide a scientific basis for forest ecosystem material circulation research in Xinglong Mountain of Gansu Province. [Methods] A field litterbag experiment was conducted in Xinglong Mountain from 2013 to 2016. Litter leaf of three main tree species including Picea wilsonii, Populus davidiana and Betula platyphylla was taken as the research object. Samples of litterbags were retrieved at May, August and November in every year. The litter decomposition rate and their initial quality were studyed. The relationship between litter decomposition rate and their initial quality were clarified. [Results] The leaf decomposition rate of P.wilsonii in middle aged forest was 0.16, and the 95% decomposition period was 19.08 a. The leaf decomposition rate of P.wilsonii in pre-mature forest was 0.13, and the 95% decomposition period was 23.70 a. The decomposition rate of litter leaf for P.davidiana and B.platyphylla was 0.11, and the 95% decomposition period was 28.57 a and 27.27 a, respectively. The decomposition rate of litter leaves of P.davidiana and B.platyphylla was significantly lower than that of the needle leaf of P.wilsonii, which was probably due to the home-field advantage of litter decomposition and smaller aperture of decomposition bags. The litter decomposition rate was positively correlated with N content, but negatively correlated with lignin content, C/N value, lignin/N and K conten. Especially, for lignin content, N content and lignin/N values, the correlation coefficients were above 0.7 000. K content, content of lignin, lignin/N, C/P and cellulose content were key indicators affecting the decomposition rate of forest litter in Xinglong Mountain. [Conclusion] Lignin/N is a key quality indicator affecting litter decomposition rate. The higher the initial lignin/N value of litter leaves, the lower the decomposition rate.

Abstract:[Objective] To collect soil samples covered by four different types of vegetation (mudflat, Suaeda glauca, Phragmites australis and Spartina alterniflora) around Jiaozhou Bay coastal wetland in Qingdao City, Shandong Province, in order to explore the leaching characteristics of soil dissolved organic carbon (DOC) in coastal wetland. [Methods] The DOC contents of soil leachate from the soil samples were determined by soil column leaching test in laboratory, and the DOC structure was analyzed by UV-visible spectrophotometry. [Results] The DOC content in soil leachate increased with the increase of soil depth. The highest DOC content was 23.12 mg/L in soil leachate from P. australis, followed by the S. glauca (15.22 mg/L), S. alterniflora (14.44 mg/L) and mudflat (8.38 mg/L). The aromaticity and humification of DOC in the soil leachate of the S. glauca was the highest, and the molecular weight and aggregation degree of DOC in the soil leachate of S. alterniflora was the largest. With the increase of soil depth, the aromaticity and humification of DOC in the soil leachate increased, while the molecular weight and aggregation degree decreased. [Conclusion] The decomposition of vegetation residues and the difference in soil desorption capacity are the main factors influencing the DOC concentration of leachate in different soil layers. The vegetation type is the key factor affecting the DOC chemical structure in soil leachate.

Abstract:[Objective] To explore the impact and dynamic changes of landscape patterns on the soil erosion process, in order to provide a basis for ecological protection and restoration in the upper reaches of Minjiang River. [Methods] Landscape ecology theory and universal soil loss equation were applied to analyze the changes of soil and water loss and landscape pattern in Zagunao watershed in the upper reaches of Minjiang River between 1990 and 2015. [Results] The soil and water loss and landscape pattern of Zagunao Watershed changed obviously during the period from 1990 to 2015. The area of grassland increased from 70125 hm to 82568 hm, and the area of forest and farmland increased slightly. The area of unused land and other land reduced 12542 hm. The vegetation coverage had increased while the soil erosion had decreased significantly during the past 25 years. The area of soil erosion with moderate erosion intensity or higher had decreased, and the area of extreme erosion reduced 36102.69 hm.[Conclusion] The restoration of grassland effectively reduced the amount and intensity of soil erosion in the study area during the past 25 years.

Abstract:[Objective] To explore the relationship between groundwater depth and plant community characteristics and soil physicochemical property, in order to provide a basis for the healthy and harmonious development of ecological environment in Tongliao Plain of West Liaohe River basin. [Methods] Based on the methods of space-time substitution and soil single fractal, the vegetation community characteristics and soil physicochemical property were quantitatively analyzed, and their response mechanism to the change of groundwater depth was discussed. [Results] ① The order of the vegetation diversity indexes under different groundwater depth was showed as: 2-3 m > 1-2 m > 4 m > 3-4 m > 0-1 m. ② The topsoil particles were mainly composed of silt with the content between 52.03% and 84.78%. The average size of soil particles was ranked as: 3-4 m, >4 m, 0-1 m, 1-2 m and 2-3 m. ③ The kurtosis were all very narrow. The fractal dimensions were between 2.34 and 2.49. The distributions of soil particle size were all in poor sorting. Correspondingly, the skewness were nearly symmetrical, nearly symmetrical, nearly symmetrical, negative sand negative, respectively. [Conclusion] With the change of groundwater recharge conditions, the succession of vegetation community in the study area is a process from non-zonal meadow vegetation to the zonal typical steppe vegetation. The critical range of vegetation succession is 2-3 m underground water depth.

Abstract:[Objective] To study the impacts of vegetation restoration stage on ecosystem carbon stocks of red soil regions in Southern China, in order to provide theoretical support for establishing reasonable forest management mode in Pinus massoniana plantation. [Methods] We studied the changes of carbon stocks in plant and soil pools in bare land, Pinus massoniana plantations with different age (10, 20 and 30 years old), and natural secondary forests in Hetian Town, Changting County in Fujian Province. [Results] The restoration of P. massoniana plantations could significantly improve the ecosystem carbon stocks. Compared with bare land, the carbon stocks in 0-10, 20-30, and 30 years old P. massoniana plantations was increased by 2.80, 3.54 and 8.56 times, respectively, but still lower than that in natural secondary forest. The restoration of P. massoniana plantations could increase carbon stocks in the surface (0-10 cm) soil, but had no significant effect on the carbon stocks of deep soil. The increase rate of soil carbon storks was different at different vegetation restoration stages, showing a non-linear increase. [Conclusion] Vegetation restoration on the eroded red soils could improve ecosystem carbon stocks in Southern China, but soil C restoration in this region was a long-term and slow process. Thus, we should pay more attention to protect natural vegetation and avoid soil erosion induced by the vegetation deterioration.

Abstract:[Objective] To accurately estimate the amount of soil erosion in flood plain of the Yellow River and hilly regions of Xuzhou City, Jiangsu Province, and explore its temporal and spatial variation, in order to provide reasonable basis for the monitoring and prevention of soil erosion in the region. [Methods] We used USLE model to calculate the soil erosion modulus in flood plain of the Yellow River and the hilly area in Xuzhou City from 2000 to 2014. The maximum, average and grades of the erosion modulus were statistically calculated, and the variation regularity of these indexes over 15 years was analyzed. The regression coefficient image of erosion modulus over the years was calculated, and the variation of soil erosion degree in Xuzhou City was revealed at temporal and spatial scale. [Results] ① Soil erosion in flood plain of the Yellow River and the hilly area of Xuzhou City was dominated by mild erosion, and the erosion in the hilly area showed a zonal distribution with greater erosion grade range. ② Soil and water loss in the Xuzhou City area was gradually weakening, and the intensity and significance of erosion in the hilly area was greater than that in flood plain. ③ The eroded area at each level decreased gradually with the increase of the erosion degree. The extremely intensive erosion area in the flood plain was controlled within 5%, while the erosion area of the extreme intensive in the hill area was controlled within 10%, and the severe erosion in both areas was contained. ④ The areas with greater erosion reduction were mostly distributed around river and lakes, and the regions with significant variations were also distributed near the rivers. [Conclusion] The intensity of soil erosion in Xuzhou City has been weakened over the years, especially in the river basin. However, in some areas of the flood plain, erosion is still increasing. The relevant departments in Xuzhou City should strengthen prevention and control efforts in these areas.

Abstract:[Objective] To investigate the effects of grassland reclamation on the variation of soil aggregates and organic carbon distribution, in order to provide theoretical basis for land use optimization and grassland protection of Siziwang Banner, Inner Mongolia. [Methods] Three soil types (chestnut soil, gray cinnamon soil and meadow soil) were selected from the grassland and cultivated land in the farming-pastoral ecotone of Siziwang Banner, Inner Mongolia. The composition of soil aggregates, soil organic carbon, and soil organic carbon of aggregates with different particle sizes and their contribution rate in the 0-10 cm soil layer were analyzed. [Results] The content of aggregates with particle sizes >3 mm and 0.25～3 mm were lower, but the content of aggregates with particle size ≤0.25 mm was higher in cultivated land than in grassland with chestnut soil and gray cinnamon soil. Moreover, and soil organic carbon of each soil aggregates with different particle size were lower in cultivated land, compared with the other two soil types. The main body of organ carbon storage transformed from soil aggregate with particle size >3 mm to 0.25～3 mm soil aggregate. The contribution rate of non-aggregates to soil organic carbon was increased in the cultivated land soil. The structure of meadow soil was poor with low organic carbon content, which was mainly caused by the salinization, but it was improved by the long-term cultivation and application of organic fertilizer after reclamation for arable land. [Conclusion] After reclamation of the grassland with chestnut soil and gray cinnamon soil into cultivated land, soil structure was degraded and the stability of soil organic carbon was decreased, however, proper reclamation in meadow soil was feasible under suitable conditions.

Abstract:[Objective] To identify the relationships between plant community characteristics and soil water storage following natural vegetation restoration after farmland abandonment, in order to provide a reference for vegetation restoration on the Loess Plateau. [Methods] Samples were collected in plots with different natural restoration years (3, 8, 13, 46, 66 and 89 a), to quantify the changes in soil water (0-100 cm) and ecological characteristics such as plant biomass and plant diversity in the Yunwu Mountain in Guyuan City, the Ningxia Hui Autonomous Region. [Results] With the succession of grassland, the plant community coverage, biomass and species diversity index increased dramatically at the early successional stages (before 13 a), and then gradually stabilized. Soil water content showed an increasing trend along the vegetation restoration years. The succession of vegetation communities had no significant effect on soil water storage in the 0-40 cm soil depths, but in the later stage of succession, the water content below 40 cm depths showed an obvious decreasing trend. Vegetation biomass and species diversity index were positively correlated with soil water content at 0-10 cm depths. [Conclusion] Soil water in the topsoil played a positive role in the variations of plant biomass and species diversity induced by vegetation restoration. However, the increase of the root biomass in the deep soil increased the consumption of soil water storage, especially in the later successional stage.

Abstract:[Objective] To analyze the effect of geomorphic units and land use on the spatial variation of total phosphorus in a small watershed of the Loess Plateau, in order to provide basis for land management. [Methods] In 2017, 267 soil samples were collected in the Wangdonggou watershed. The total phosphorus contents were measured for different geomorphic units and land use types and its spatial distribution was mapped by using ArcGIS 10.2. [Results] The land use patterns and geomorphologic units exhibited an extremely significant effect on the spatial variation of total phosphorus. The content of total phosphorus in different geomorphic units showed as: sorghum> slop> channel. The content of total phosphorus in different land use types showed as: orchards> abandoned orchards> farmland> woodland> wild grassland. [Conclusion] After more than ten years of agricultural intensification, the total phosphorus content has been improved greatly, and the distribution of total phosphorus has been substantially changed by the land use patterns.

Abstract:[Objective] To analyze the influence mechanism of water and salt contents on soil nutrient and enzymatic activity, in order to provide scientific basis for exploring the effect of seawater intrusion on coastal wetland soil. [Methods] The surface soil of the coastal wetland in Jiaozhou Bay was collected and the simulation experiments were conducted in laboratory to determine the soil nutrient index and enzymatic activity under different water salt gradients. [Results] Soil pH value and bulk density (BD) were significantly affected by salinity and moisture, respectively. With the increase of soil water gradient, the total organic matter (TOM), ammonium nitrogen (NH₄⁺-N), available phosphorus (AP), available potassium (AK), sucrase activity (SA), urease activity (UA) and alkaline phosphatase activity (APA) increased initially and then decreased, reaching the maximum value at 30% water gradient. TOM, AP, AK, SA, UA and APA decreased with the increase of soil salinity gradient, while NH₄⁺-N showed an opposite variation trend. The correlation analysis showed that SA was positively correlated with TOM, AP and AK, and APA was positively correlated with TOM, AP, AK and BD. In addition, UA was positively correlated with soil pH value and BD, and had a certain correlation with NH₄⁺-N. [Conclusion] In a certain range, excessive or low water content and increased salt content can inhibit the soil nutrient contents and enzymatic activities, and there is a close relationship between soil nutrients and enzyme activities.

Abstract:[Objective] This paper studied the water use mechanism of farmland shelterbelts with important protection function under the mode of farmland water-saving irrigation, in order to provide a scientific basis for optimizing irrigation of the local farmland and farmland shelterbelt. [Methods] The stable oxygen isotope (δ¹⁸ O) was used to study the water use mechanism of Populus euphratica, Elaeagnus angustifolia and Ulmus pumila in the arid oasis areas under farmland water-saving irrigation mode. The results were compared and analyzed based on the direct judgment method, IsoSource model and water absorption depth model. [Results] The sources of water use was different for different tree species at vary time. In April, P. euphratica mainly used 10-20 cm of shallow soil water, and its contribution rate was 83.3%. E. angustifolia mainly used deep soil water at 80-120 cm and 120-160 cm depth with contribution rates of 50.6% and 16.9%, respectively. Whereas, 82.5% water usage of U. pumila was from 50-300 cm depth of soil water and groundwater. In May, 57.1% of water used by P. euphratica was from 0-30 cm shallow soil water. Surface soil water at 0-10 cm soil depth contributed 50.8% and 52.7% for the water usage of E. angustifolia and U. pumila, respectively. In June, the contribution of water source for P. euphratica usage was 38.7% from 0-20 cm shallow soil, while 10.5% from groundwater. And 76.9% of the water content of E. angustifolia came from shallow soil of 10-20 cm, 49.1% of water usage for U. pumila came from 0-80 cm soil, and another 12.3% from groundwater. The average water absorption depth of P. euphratica was 18, 28, 25 cm, respectively in April, May and June. For E. angustifolia, it was 118, 37, 34 cm, respectively. At the same time, it was 95，37，29 cm for U. pumila, respectively. [Conclusion] When selecting farmland shelterbelt tree species, while ensuring the protection benefit of shelterbelt, we should choose the species with deep soil water or groundwater as the main water source, so as to exert the protective effect of farmland shelterbelt more efficiently.

Abstract:[Objective] To investigate the influence of compactness on water transport characteristics of iron tailings sand, in order to provide scientific support for soil and water conservation and vegetation restoration in iron mining area. [Methods] The infiltration process and water characteristic curves were measured by means of one-dimensional soil column test and tensometer method at five bulk weight levels of 1.50, 1.55, 1.60, 1.65 g/cm³ and 1.70 g/cm³. [Results] ① As the bulk density increased, the infiltration capacity of iron tailings decreased, and the bulk density had a significant linear negative correlation with the stability of the iron tailings, the cumulative infiltration and the wetting peak distance (p<0.05). ② The water content of the tailings of 1.50~1.60 g/cm³ was obviously stratified with depths, and the water content of the tailings sands of 1.65 g/cm³ and 1.70 g/cm³ was less. ③ The correlation coefficient between the saturated hydraulic conductivity of the iron tailings and the measured value of the Green-Ampt model was 0.886, and the calculation accuracy was high. The Kostiakov model was the best for fitting the different weight-bearing iron tailings infiltration process (R²=0.989). ④ During the dehumidification process, the water holding capacity drop significantly at levels of high bulk density made. The water holding and water retention performance was the best at levels of 1.60 g/cm³. The water characteristic curve fitted with van Genuchten model showed that the saturated water content, residual moisture content, air intake value and shape coefficient decreased with the increase of bulk density. [Conclusion] High compactness seriously inhibited water infiltration and water holding capacity of iron tailings. Loosing tailings matrix should be used to improve the structural properties in the reclamation.

Abstract:[Objective] To explore the effects of different organic matter on soil fertility of newly reclaimed land, in order to provide a scientific basis for subsequent fertilization management of newly reclaimed land. [Methods] Taking three different organic matters as the influencing factor and blank as the control, a 3-year continuous plot experiment was conducted, under a vegetable planting pattern of tree harvest a year, to investigate the effects of different organic matter on fertility and vegetable growth in newly reclaimed red soil. [Results] Among three kinds of organic matters, the treatment of commercial organic fertilizer showed the best effect on newly reclaimed red soil and vegetable growth. [Conclusion] The commercial organic fertilizer can be recommended as one of the foreign organic matter applied in newly reclaimed red soil region. The effect of edible fungus residue is the second, which can be used as an alternative product. The effect of rice straw is poor.

Abstract:[Objective] We aim to understand the spatial distribution law of soil nutrient in Pingshuo mining area in Shuozhou City, Shanxi Province, in order to provide the basis for fertilization decision in the future, and to accelerate the improvement in soil condition in mining area. [Methods] We took Pingshuo mining area as the research area, and collected 30 groups of soil samples respectively from mining undamaged areas, mining damaged areas and harnessing areas. The soil nutrient content was then measured by experiments and analyzed by R and Sufer, to obtain nutrient changes in different areas. Finally, the soil nutrient status was comprehensively evaluated based on the membership value and weight coefficient of each nutrient factor in the sample. [Results] Compared with soil nutrient content grading and the standard of nutrient abundance and deficiency, the nutrient was in a status of deficient or acute deficient in Pingshuo mining area. Except for pH value, the variation coefficients and content of other nutrient indexes fluctuated greatly, especially in the undisturbed areas. Although land reclamation could improve the damaged soil of the mining area to a certain extent, it would take a long time for the damaged soil to be recovered to the status before mining. [Conclusion] Mining and land reclamation in Pingshuo mining area have important influence on soil nutrient content and distribution.

Abstract:[Objective] We aim to investigate the effects of heavy metals in surface sediments of catchment rivers in drinking water source areas (Dongpu reservoir and Dafangying reservoir) in Hefei City of Anhui Province on downstream reservoirs. [Methods] Twenty-three sediment samples were collected from three major river catchment to determine the concentrations of Zn, Cu, Cr, As, Cd, Pb and Hg. The potential ecological risk was assessed by the potential ecological risk index (I_R) and cumulative index method (I_geo). The principal component analysis was used to assess the possible sources of the heavy metals. [Results] The distribution of heavy metal in the study area was different. The contents of As and Cd in sampling locations of C₁ and C₂ on the Surabaya river exceeded the secondary standard limit of soil environmental quality for maintaining human health, and the available Cd in these two sites accounted for 34.97% and 37.67% of total Cd concentration, showing a strong biological availability. Cd ecological risk index was generally high, reaching the intensity level, among which C₁ and C₂ on the surabaya river reached the extremely strong level. In addition, the ecological risk of Hg for location S₈ reached the intensity level, and the ecological risk level of the remaining 6 heavy metals was relatively low. The heavy metals in this region mainly came from human-natural mixed sources and human-made sources, with contribution rates of 51.11% and 27.70%, respectively. [Conclusion] Cd pollution is more serious in the lower reaches of the Sishui River. In order to reduce its impact on the downstream reservoir, Cd pollution control should be strengthened.

Abstract:[目的]探索适用于喀斯特地表干旱遥感监测的技术方法，为石漠化治理监测以及抗旱减灾工作提供技术参考。[方法]运用大气校正法反演地表温度（T_s）和归一化植被指数（NDVI），构建花江峡谷区2013年、2014年和2015年旱季的温度-植被干旱指数（TVDI），并结合地面实测数据对TVDI作为旱情指标进行了验证。[结果]①反演的TVDI与同时期实测的0-10 cm土壤体积含水量数据呈显著的负相关关系（p<0.05）。②3个时期的干旱等级以轻旱为主；轻旱、干旱和重旱累计面积占全区比重大，呈现2014年旱情重于2015年和2013年的特点。③3个时期的旱情在空间分布上，湿润和正常等级在地形上主要分布在海拔900~1 100 m地带，15°~35°的斜坡和缓陡坡，以及阴坡和半阳坡；在石漠化等级上，主要分布在无石漠化区、轻度石漠化区和潜在石漠化区；在土地利用类型中主要分布在有林地、旱地、灌木林地和其他林地。轻旱、干旱和重旱在地形上主要分布在海拔500~900 m，6°~25°的缓坡和斜坡，以及阳坡和半阳坡；在石漠化等级上，轻旱和干旱主要分布在轻度石漠化区、潜在石漠化区、中度石漠化区和强度石漠化区，重旱主要分布在非喀斯特区；在土地利用类型上，轻旱、干旱和重旱主要分布在旱地、园地和其他林地。[结论]TVDI可作为研究区的干旱监测指标，基于TVDI和Landsat-8数据的干旱监测方法在喀斯特峡谷区具有一定适用性。

Abstract:[Objective] The ecological cleanliness in the small watershed of the typical ecological clean basin in South Sichuan Province was evaluated, in order to effectively guide the formulation of the implementation plan for the construction of ecological clean and small watershed in mountainous areas, and to provide scientific theory and data support for the construction of ecological clean small watershed in similar areas and the evaluation of its effect. [Methods] Based on the principles of representativeness, operability and applicability, according to the natural, social and economic characteristics of the Qingxigu small watershed, a comprehensive evaluation index system for eco-cleanliness evaluation in Qingxigu watershed was established by fuzzy mathematics method and analytic hierarchy process. [Results] The comprehensive evaluation index system of ecological cleanliness in Qingxigu watershed included 3 subsystems: ecological region, production region and living region, and 24 evaluation indices were chosen. The weight of the ecological index of watershed regulation of water system and soil conservation measurements was 0.247, the weight of ecological agriculture development was 0.373, the weight of renovating environment of human settlements was 0.380, and the total value of the ecological clean watershed was 0.772, reaching the ‘clean’ level. It indicated that the Qingxigu small watershed was in a healthy, coordinate and stable development. [Conclusion] The construction of eco-clean small watershed could improve the local agricultural condition, adjust production structure, control the non-point pollution, supply the pure and clean water resource and accelerate the sustainable development of the watershed.

Abstract:[Objective] To study the selection of rain garden plant in North He'nan Province, in order to provide theoretical support for the construction of rainwater garden and sponge city. [Methods] We investigated the 29 typical rain garden plants in the sponge city of Hebi and An'yang City in He'nan Province. Rain garden plants were comprehensively evaluated by analytic hierarchy process (AHP), and the evaluation system was constructed from three criterion layers and 9 index levels. [Results] Drought resistance, humidity resistance, greening and beautifying characteristics, decontamination and pollution reduction ability showed important influences on the selection of plants in rain garden. Lythrum salicaria, Polygonum orientale, Pennisetum orientale, Iris tectorum, Miscanthus sinensis "Gracillimus", Miscanthus sinensis "Variegatu" were evaluated as level 1. Thalia dealbata, Dianthus plumarius, Hylotelephium erythrostictum, Canna indica, Coreopsis drummondii, Verbena officinalis, Dahlia pinnata were evaluated as level 4. The rest of sixteen plants were evaluated as level 2-3. [Conclusion] Plants with a comprehensive evaluation level 1 are the optimal choice for the construction of rainwater gardens in Yubei District. Plants with a comprehensive evaluation level 4 need to be carefully selected for rainwater gardens. Integrated evaluation of plants with level 2-3 are suitable to be planted in areas such as water storage areas, buffer zones, and marginal areas.

Abstract:[Objective] To study the trinity dynamic construction comprehensive efficiency rate of "resource efficiency-environment efficiency-economic efficiency" in the construction of railway dregs field, in order to provide the basis for the study of soil and water conservation and long-term benefit brought by the application of "four sections and one environmental protection" in the construction of railway dregs field. [Methods] The green construction concept and the multidimensional benefits of soil and water conservation was considered. The traditional Malmquist model was employed as a foundation. The construction of dregs field was taken as the research subject, the Malmquist model (QMPI) for construction of railway dregs field was established by introducing the unexpected production caused by construction, with the fully consideration of the utilization of resources and the long-term effects of dynamic investment. [Results] QMPI fully explained the dynamic construction comprehensive benefits of the "resource efficiency-environmental efficiency-economic efficiency" of the railway dregs field. The construction total factor productivity and decomposition efficiency of QMPI were calculated based on the DEA-SOLVER PRO software platform. Meanwhile, the redundancy rate of each element was analyzed. [Conclusion] The construction comprehensive efficiency rate is positively correlated with resource efficiency change (REC)and environment efficiency change(EEC), that is, green construction will promote the comprehensive benefit rate of construction. At the same time, the promotion of the "four savings" will promote "one environmental protection" and thus work together for higher construction benefits.

Abstract:[Objective] To study the landslide displacement prediction model, in order to provide a scientific basis for government departments to implement more reliable disaster prevention and control decisions. [Methods] An iterative unscented particle filter (IUPF) method based on singular value decomposition (SVD) constrain was proposed to establish a landslide displacement prediction model based on displacement parameters. [Results] The SVD method was effectively improved the robustness of Sigma point calculation in the unscented particle filtering method, thereby improving the prediction accuracy of the algorithm and making a more accurate prediction of the landslide stability trend. The algorithm was applied to the application and analysis of the data related to the monitoring project of the Paomashan landslide in Zhenjiang City and the landslide monitoring project on the south side of the Yuhua Interchange in Beijing-Hong Kong-Macao Expressway. [Conclusion] The prediction in landslide displacement with the unscented particle filtering algorithm with SVD constraint can be more accurate, and the predicted data can reflect the deformation trend of the landslide more accurately.

Abstract:[Objective] To calculate the benefits and cost of four green water management measures, in order to provide a new reference pattern for ecological restoration of Xixi watershed, and provide support for improving water resources management mechanisms. [Methods] Taking Xixi watershed of the Jijiang basin as the study area, four green water management measures including stone lines, bench terraces, contour tillage and mulching were simulated by soil and water assessment tool (SWAT) model. The benefits of four measures in increasing green water, soil conservation, water quality protection and agricultural income were calculated, and the benefit and cost of each measure was analyzed. [Results] ① The benefit-cost ratio of stone lines, bench terraces and contour tillage was 19.52, 13.03 and 6.98, respectively, which were far greater than 1, so those three green water management measures were suitable for popularization and application in Xixi watershed. The average benefit-cost ratio of the three measures was 10.18, and the average cost of the three measures in Xixi watershed was 3.97 million RMB per year, and the average benefit of that was 40.47 million RMB per year. ② The benefit-cost ratio of mulching was only 0.63, so it was not suitable for application in the study area at present. [Conclusion] The environmental and economic benefits of stone lines, bench terraces, contour tillage are good and have a good application prospect. Further exploration should be made to reduce the cost of mulching, and the financial subsidies are also need to be provided, so as to promote the application of the green water management measures in the study area.

Abstract:[Objective] We aimed to solve the problem of monitoring data noise and boundary ambiguity in comprehensive evaluation of agricultural water quality, in order to establish a comprehensive evaluation model with good disturbance resistance and grade division. [Methods] A data-driven fuzzy support vector evaluation method was proposed to determine index weight of projection pursuit index and the parameters of fuzzy membership. Improved genetic algorithm was adapted to optimize the projection pursuit function and obtain the relatively objective index weigh. Then the parameters of fuzzy membership were optimized with data, and a comprehensive evaluation model of fuzzy support vector machine was constructed to reduce the influence of monitoring noise on the generalization ability of the evaluation model. In addition, considering the low resolution of the general discrete evaluation grade, the concept of regional division reliability was proposed to explain the reliability of the regional division grade of the sample, to further explain the comprehensive evaluation results. [Results] The model evaluation results were consistent with the results from experts and traditional evaluation. The model maintained more than 85% consistent rate with the monitoring data with 10%～30% random noise, and the reliability of regional division of samples was greater than the critical value, indicating the reliability and robustness of the method. The results from the constructed model were better than the fuzzy comprehensive evaluation and grey clustering method. [Conclusion] The method proposed by the present study is feasible and robust, and it can provide a reference for real-time evaluation of agricultural water quality under the condition of subsequent noise.

Abstract:[Objective] To study the health status of cultivated land resource utilization system in Anhui Province during 2007-2016 in order to provide references for future work. [Methods] The DPSIR index evaluation system was constructed, and the health status of cultivated land resource utilization system in Anhui Province in the past 10 years was measured by using TOPSIS model. Meanwhile, the obstacle model was used to analyze the main restrictive factors. [Results] From 2007 to 2016, the health level of cultivated land resource utilization system in Anhui Province was changed from unhealthy to sub-healthy, and the health condition was improved significantly. Generally, the most serious obstacle in the health criteria of cultivated land resource utilization system was the pressure subsystem. The main obstacles were GDP growth rate, crop disaster area, pesticide use, farmland occupied by construction, and agricultural plastic film use. [Conclusion] Using DPSIR model to construct the evaluation index system of cultivated land resources utilization system and using TOPSIS method to analysis the health level of cultivated land resource utilization system is feasible in Anhui Province. Although the overall health level in Anhui Province shows a steady upward trend, the utilization system of cultivated land resources is still at a sub-health level limited by the pressure subsystem.

Abstract:[Objective] This study is to analyze the ecological change in Bole City of Xinjiang Wei Autonomous Region by remote sensing method, in order to provide a theoretical basis for ecological protection. [Methods] The Landsat images of Bole City in 1997, 2007 and 2016 were collected as data sources, and four indexes including greenness, humidity, dryness and heat were extracted. The principal component analysis was applied to couple the remote sensing ecological index(RSEI), to monitor and evaluate the ecological environment quality of Bole City. [Results] The research area belongs to the mountain-oasis-desert system(MODS), and the overall RSEI was very low in 1997, 2007 and 2016. The ecological environment quality of Bole City showed a significant improvement trend from 1997 to 2016, as the RSEI increased from 0.250 to 0.422 and the proportion of excellent and good leveles increased from 11.24% to 26.20%. The improved areas were mainly distributed in the northern mountains, the central oasis, the Southern Tianshan Mountains and the western deserts at the northern foot, which were significantly larger than the degraded area. The deteriorated areas were mainly concentrated in the cultivated land and urban construction areas in the central oasis. [Conclusion] The construction of desert ecology and the expansion of oasis have a positive impact on the improvement of ecological environment. In addition, rational resource allocation and land utilization should be carried out as well.

Abstract:[Objective] To reconstruct health process of the Yarkant River using various hydrological methods, in order to provide scientific basis for ecological regulation and control based on river health. [Methods] Monthly discharge data from the Kaqun hydrological station in Xinjiang Wei Autonomous Region from 1957 to 2015 were analyzed. Based on the river restoration targets including river morphology, hydrological condition, and health of the river ecosystem, considering the functional requirements and the accessibility, the river protection objectives were divided into conservative and optimal objectives. To reconstruct a healthy discharge pattern in the Yarkant River, the improved Tennant method, Texas method, the monthly guarantee rate method, and the water demand empirical formula for sediment transport were used. [Results] ① Under conservative river protection targets, healthy discharge during the low flow period, common flow period, and high flow period was 4.93, 13.35, 80.49 m³/s, respectively, the discharge converted water volumes were 5.20×10⁹, 1.41×10⁸, 8.48×10⁸ m³, respectively. While the total annual water requirement for river health was 1.19×10⁹ m³, considering sediment transport demand. ② Under optimal river protection targets, healthy discharge during the low flow period, common flow period, and high flow period was 14.95, 24.14, 182.12 m³/s, respectively, and the outcome converted water volumes were 1.56×10⁸, 2.54×10⁸, 1.92×10⁹ m³, respectively. With the consideration of sediment transport demand, the annual water requirement for river health was 2.33×10⁹ m³. [Conclusion] In comparison with relevant literature and data, it is considered that the research results are reasonable, and it can provide scientific guidance for the river health and water resources regulations and ecological protection in future.

Abstract:[Objective] To quantitatively reveal the spatial distribution and change characteristics of ecological environment quality in Yangling Agricultura Hi-tech Industries Demonstration Zone, in order to provide scientific basis for the planning and management of ecological environment construction. [Methods] Landsat 8 satellite images were collected, the remote sensing ecological model and principal component analysis was employed. [Results] From 2013 to 2018, the ecological environment quality of the district showed an overall upward trend, the average value of remote sensing ecological index increased from 0.45 to 0.50, and the area with an upward trend was 50.77 km², accounted for 38 % of the total area of the region. The ecological environment in the district was better in the northwest than in southeast. The dryness component had the greatest effect on the ecological index model. [Conclusion] The areas with poor ecological environment quality in the district are mainly concentrated in the urban areas with intensive human activities and large industrial parks. In the future planning and development of the district, the area of bare land and construction land should be controlled and reduced, and more attentions need to be paid to ecological landscape and urban greening.

Abstract:[Objective] To analyze the dynamic changes of regional soil erosion intensity and its driving factors, in order to provide scientific basis for regional soil and water conservation. [Methods] Based on 3S technology, the revised universal soil loss equation (RUSLE) was used to estimate soil erosion modulus of Meihekou City, Jilin Province in 2010 and 2017. The changes of soil erosion were analyzed according to land use, slope and soil and water conservation measures. [Results] ① The average soil erosion modulus in 2000 and 2017 were 698.75 and 678.25 t/(km²·a), respectively, indicating the improvement of soil and water conservation in Meihekou City. ② The soil erosion in Meihekou City was correlated with the slope and land use. More than 95% of the soil erosion area were distributed in areas with slope <15°, and the land use was mainly cultivated land and forest land. ③ From 2010 to 2017, the mean soil erosion modulus decreased by 154.08 t/(km²·a), and the amount of soil erosion decreased by 2.65×10⁴ t in the soil and water conservation project implementation area. [Conclusion] The implementation of soil and water conservation project have improved soil and water conservation functions dramatically, but soil erosion is still existing in the treated area, and the improper transformation of land use type has aggravated regional soil erosion. Therefore, the cooperation works among different department need to be done to control the soil and water loss from the sources.

Abstract:[Objective] To study the effect of three-dimensional topography on shear strength and reveal the shear essence of structural plane, in order to provide the basis for understanding the properties of structural plane. [Methods] A 3D laser scanner and a 3D printer was used to completely recast the artificially fabricated structural interview samples. The direct shear test was conducted indoors under the normal stress level 5, to record the surface topography change before and after shearing. The FLAC 3D numerical simulation software was used to simulate the shear mechanical movement of the structural plane under different normal pressures. The distribution of shear stress on the surface of structural plane was analyzed and summarized. [Results] The peak shear strength of the structural plane was related to the normal pressure and three-dimensional topography of the structural plane. Under the same shearing force, with the larger normal stress, the shearing contact area, the shearing stress and the scope of the shearing stress were larger. The small bulge at the top of the structural plane surface was significantly sheared, but the damage area of the small bulge at the lower part was not obvious, indicating that the bulge at the higher part of the structural plane was easier to be sheared. [Conclusion] With the increase of normal pressure, the magnitude and range of shear stress increase, but the region does not change obviously.

Abstract:[Objective] To establish the niche-fitness evaluation index system for cultivated land consolidation from the perspective of ecological suitability, in order to provide scientific references for making differentiated cultivated land consolidation policies. [Methods] Based on niche theory, 10 indicators from three index layers (potential productivity, spatial pattern, location condition) were used to establish the niche-fitness evaluation index system for cultivated land consolidation of the loess hilly region. Taigu County of Shanxi Province was taken as an example. The niche-fitness value in each research unit was determined by the matching degree between the actual and optimal ecological niche of cultivated land. The standard classification method based on GIS was used to divide the priority of cultivated land consolidation. Finally, cultivated land consolidation modes in different areas were determined. [Results] The niche-fitness value of cultivated land consolidation in the study area ranged from 26.02 to 93.57, and the overall distribution was uneven. According to the niche-fitness evaluation results, the study area could be divided into priority consolidation area, general consolidation area and restricted consolidation area, accounting for 49.50%, 30.28% and 20.22% of the cultivated land area, respectively. The results of division were basically consistent with the present situation of cultivated land utilization in the study area. Through the combination analysis of key indicators, three modes of cultivated land consolidation were identified: transforming slope farmland to terraces, construction and perfection of farmland irrigation and water conservancy, and improving road accessibility. [Conclusion] It is feasible to study the priority of cultivated land consolidation by using niche-fitness model.

Abstract:[Objective] This paper aims study the location selection, design planning, scientific management and ecological environment construction of photovoltaic power stations in desert areas in order to provide basis for the sustainable development of photovoltaic industry and ecology. [Methods] By analyzing a large number of references and related topics, the influences of the photovoltaic power station construction and operation period on soil, vegetation, climate, animals, microorganisms and other ecological factors were analyzed, to reveal the disadvantages of the existing photovoltaic power stations in ecological environment, and to predict the future application prospect and development direction. [Results] The construction period of the power station could cause some short-term adverse effects on plants and environment. However, during the operation period, due to wind resistance, sand fixation, shading and humidification of photovoltaic array and artificial management, it was beneficial to vegetation restoration, soil improvement and local microclimate improvement in the sand area. [Conclusion] In the future, the influence of photovoltaic power stations on the ecological environment should be further studied and the corresponding prevention measures should be implemented, to ensure the ecological balance and realize the friendly and coordinated development of photovoltaic power generation and the ecological environment.

Abstract:[Objective] To explore whether the relationship among ecological protection, production development and life improvement can be coordinated in the process of poverty alleviation and development in Tujia and Miao Autonomous Prefecture in Hu'nan Province, in order to realize the centralized integration of poverty alleviation resources and seek the appropriate model for poverty alleviation and development in poverty-stricken counties in key ecological functional areas. [Methods] Based on the precise poverty alleviation strategy in combination with the living, production and ecology win-win theory, the poverty alleviation evaluation index system was built, and the weight of the index was determined by objective and subjective weighting method. Then the production, living and ecology index and comprehensive poverty alleviation performance index of the research area from 2010 to 2016 was calculated. [Results] ① The poverty alleviation performance in West Hu'nan Province had been improved, and the comprehensive index of poverty alleviation performance had increased by 2~4 times in the past six years, especially after the implementation of the precise poverty alleviation strategy. ② The production index in poverty-stricken areas had increased by 5.8 times on average, which was the fastest, but the research area should not focus on production development while neglect the improvement of living and ecology. ③ Poverty alleviation and development in poverty-stricken counties in key ecological functional areas should consider regional characteristics and coordinate the relations among production, living and ecology so as to achieve sustainable development. [Conclusion] The primary task of poverty-stricken counties in the key ecological functional areas of West Hu'nan Province is to get rid of poverty, but the protection of ecological environment and the improvement of living conditions are equally important, beyond economic development.

Abstract:[Objective] To explore the effectiveness of sponge city construction and its key driving factors, in order to provide theoretical basis and policy guidance for sponge city construction in different areas in China. [Methods] The evaluation index system of sponge city construction was established from four aspects including water environment safety, the utilization of water resource, water pollution control and water habitat construction. According to the topography, climate and development scale, Beijing, Chongqing and Zhenjiang City were selected as the study areas. The change of sponge city construction and its key influencing factors was quantitatively analyzed by principal component analysis and fuzzy-gray comprehensive evaluation model. [Results] From 2006 to 2015, the index of sponge city construction showed an upward trend. Of all the sub-target layer construction indexes, only the water resources utilization index of Beijing and Chongqing City has decreased. [Conclusion] Chinese sponge city construction has achieved initial success, and urbanization is closely related to the change of sponge city construction index. The construction of sponge city in North China and East China should also strengthen the control of the reservoir volume per unit area and agricultural pollution load; and based on topographic analysis, the construction of sponge city in mountainous cities should also strengthen the control of water saving and domestic wastewater discharge.

Abstract:[Objective] To evaluate the eco-security status in Xichuan County of He'nan Province, the core water source area of Danjiangkou reservoir, in order to put forward corresponding control measures to ensure the long-term performance of the middle route of south-to-north water diversion project. [Methods] Based on the improved PSR(presure-state-response) model, AHP (analytic hierarchy process) and GIS technology, the temporal and spatial evolution of ecological security in Xichuan County was evaluated. The main driving factors of ecological security in Xichuan County was analyzed by principal component analysis. [Results] ① The eco-security situation of Xichuan County fluctuated, but overall improved. Compared with 2000, the towns with medium and primary warning were reduced by 3, while the towns with the relatively safe increased by 6 in 2015. ② The spatial pattern of eco-security in Xichuan County was higher in the northeast and southwest, but lower in the northwest and southeast. ③ According to the driving force analysis, it was found that the main reason for the improvement of eco-security level in Xichuan County was the positive response of environmental governance. [Conclusion] The benign transformation of ecological security needs to promote regional eco-security and sustainable socio-economic development by actively guiding human activities and multi-raising measures.

Abstract:[Objective] To select the mixed forest types with good protection function, in order to provide a theoretical basis for guiding the optimization and upgrading of limestone mountain forests in Shandong Province. [Methodes] We selected 8 different mixed forests of 5-year-old in the typical limestone mountainous area of Shandong Province, and the Platycladus orientalis forest was used as the control. Field investigation was conducted and quantitative analysis methods were used to study the soil improvement and erosion reduction benefit from three aspects: the growth condition of mixed forests stand and benefit of improving soil physicochemical properties, the soil hydrological benefit of forest land and the soil erosion abatement benefit. Totally, 13 indexes including canopy density, crown width, tree height, soil bulk density, total porosity, available nitrogen, available phosphorus, available potassium, soil saturated water storage, steady infiltration rate, infiltration time, amount of erosion and thickness of litter layer were selected. The comprehensive evaluation of different mixed forest stands was carried out by analytic hierarchy process (AHP). [Results] The P. orientalis+Melia azedarach mingled forest had the best soil erosion reduction benefit, followed by the P. orientalis+ Robinia pseudoacaia and P. orientalis+Cotinus coggygria mingled forest. [Conclusion] The soil improvement and erosion reduction benefit of mixed forests is better than that of pure forests. The soil improvement and erosion reduction benefit of P. orientalis+M. azedarach, P. orientalis+ R. pseudoacacia and P. orientalis+C. coggygria are the best, which is suitable for limestone mountains.

Abstract:[Objective] To investigate the pollution distribution of livestock production and the spatial distribution characteristics of arable land carrying capacity in Sichuan Province, in order to provide a theoretical basis for sustainable development of agriculture in this area. [Methods] Total livestock manure production, the losses of manure pollutants, and the availability of agricultural lands were estimated. The ArcGIS was used to evaluate land resource requirements and environmental risks of livestock production, as well as agricultural carrying capacity. [Results] Total livestock manure production in Sichuan Province was 2.94×10⁷ t in 2016. The losses of pollutants were dominated by COD (chemical oxygen demand, not a pollutant), while the least was total phosphorus (TP). The average PEL (pig equivalent load), nitrogen (N) and phosphorus (P) carrying capacity was 50 310, 327, and 85 kg/hm², respectively, resulting in an average risk threshold value of 1.34 (grade Ⅳ). However, the load warming values varied greatly across the region, with the highest in Aba (6.61) and Ganzi (6.93). [Conclusion] At present, the production of livestock and poultry manure has been a threat to the environment in Sichuan Province, the source of livestock and poultry manure pollution is mainly cow dung and pig dung. The model of livestock and poultry breeding in the combination of agriculture and pastoral, breeding and ecological circulation should be promoted.

Abstract:[Objective] In order to provide reference for understory herbaceous communities management in Pinus sylvestris var. mongolica plantations, the dynamic of understory herbaceous communities were investigated and the relationships between diversity index and stand age in P. sylvestris var. mongolica plantations were explored. [Methods] The P. sylvestris var. mongolica plantations with different ages (8, 18, 27, 35 and 48-year-old) in Zhanggutai area in the Southern Horqin sandy land were selected as the study objects, the vegetation species, quantity, coverage and biomass of these plantations were investigated and the effects of stand age on diversity index were quantified. [Results] The importance value of Digitaria sanguinalis was the highest in all ages of the P. sylvestris var. mongolica plantations, indicating that the D. sanguinalis could adapt well to understory environment and was the dominant species of understory vegetation. With the increasing of stand age, the biomass and diversity of understory herbaceous vegetation decreased initially and then increased, and the lowest values occurred in the 27-year-old P. sylvestris var. mongolica plantations. Stand age showed binary regression relationships with Patrick richness index, Shannon-Wiener index, Pielou evenness index and Simpson dominance index. [Conclusion] The degradation phenomena existed understory herbaceous vegetation in half-mature and near-mature P. sylvestris var. mongolica plantations, thus artificial promoting measures such as thinning, intertillage and enclosuring should be adopted to promote herbaceous vegetation growth and succession.

Abstract:[Objective] To explore the evolution and susceptibility of landslide activity intensity in meizoseismal area of Wenchuan earthquake in order to provide important practical basis for landslide and debris flow risk management. [Methods] Twelve debris flow basins were selected as study area along Longxi River in Longchi Town, Dujiangyan City, Sichuan Province. Based on the interpretation analysis of the remote sensing images after the earthquake, the evolution characteristics of the landslide after earthquake were studied. At the same time, the probability comprehensive discriminant analysis method and the analytic hierarchy process were used to analyze the susceptibility of landslide. [Results] The 825 co-seismic landslides occurred in the region after the earthquake, and the intensity of landslide activity reduced gradually. From 2009 to 2017, 376 new landslides occurred outside of the co-seismic landslide areas. In February 2017, the number of active landslides reduced to 368, accounting for 30.6% of the total landslides. The area under curve (AUC) method was used to test the multi-period evaluation results, the accuracy was 75.6% to 81.4%, and the evaluation results were satisfactory. [Conclusion] The number of active landslides after earthquakes and the area of high sensitive zone in meizoseismal area show a decreasing trend, indicating that the landslides after earthquakes are in the process of gradual recovery, but the activity intensity of geological hazards is still far higher than that before the earthquake.

Abstract:[Objective] To analyze the response relationships between vegetation cover and temperature and precipitation since the implementation of natural forest protection program (NFPP) in Fukang forest farm, in order to provide data support for the ecological benefit evaluation of NFPP. [Methods] Based on the MODIS/NDVI data and the temperature & precipitation data from 2000 to 2015 in Fukang forest farm, the methods of mean value, regression analysis, distance fluctuation and correlation analysis was used to explore the vegetation cover characteristics, climate change status in the farm and the response relationships between them. [Results] ① From 2000 to 2015, the vegetation cover in the study area was at a low level and showed a slight fluctuating downward trend. By analyzing the changes of NDVI at different levels, the most obvious change of vegetation cover in the past 15 years was the part of NDVI>0.65, which was the main part of the decline of NDVI in the study area. The level of ‘low’ and ‘high’ NDVI increased but was not obvious, and the level of ‘medium’ NDVI increased obviously and accounted for a relatively large proportion. ② Since the implementation of NFPP, the annual average temperature in the study area showed a fluctuating downward trend. The annual precipitation showed a significant fluctuating upward trend. ③ Since the implementation of the NFPP, the correlation coefficient between vegetation cover change and temperature change was only 0.053 9, while the correlation coefficient between vegetation cover change and precipitation change showed a significant correlation. Vegetation cover change was less affected by temperature than by precipitation. [Conclusion] Since the implementation of the NFPP, the vegetation coverage in the Fukang forest farm has showed a fluctuating downward trend, but the decline is not significant. The climate tends to change from warm and dry to cold and wet, and the trend is not obvious. The relationship between vegetation cover fluctuations and precipitation fluctuations is significantly stronger than that of temperature. The implementation of the NFPP in the Fukang forest farm has improved the surrounding climate, but it is still necessary to strengthen the protection and restoration of the vegetation in this region.

Abstract:[Objective] To analyze the spatial relationship between topographic relief and population/economy, in order to provide a reference for the rational distribution of population and the optimization of economic pattern in Sichuan Povince. [Methods] Based on ASTER GDEM data, the optimal statistical unit of topographic relief in Sichuan Province was determined by mean change-point method, and the distribution pattern of topographic relief was analyzed. The spatial relationships between topographic relief and population/economy were discussed by spatial autocorrelation analysis. [Results] Sichuan Province was mainly covered by mountains and hills, and the overall trend was high in the west and low in the east. The topographic relief was negatively correlated with population/economy, and the clustering characteristics were significant. Ganzi, Aba, and Liangshan Autonomous Prefecture were areas with high topographic relief, low population distribution, and low economic levels. Chengdu City was a region with low topographic relief, high population distribution, and high economic level. The southern part of Nanchong City and Langzhong City were areas with low topographic relief, high population distribution, and low economic level. Due to natural resources and geographical location, the topographic relief showed no significant impact on the population/economy in Renhe District of Panzhihua City, and Shiqu County of Ganzi Autonomous Prefecture. [Conclusion] The topographic relief in Sichuan Province was negatively correlated with the population/economy, but this relationship varied from region to region.

Abstract:[Objective] To analyze the geomorphological classification indicators at the micro scale, in order to provide data support for soil erosion, prevention and control of geological disasters and agricultural planning decisions in Gansu Province.[Methods] Based on the digital elevation model (DEM) data, the optimal analysis window of the geomorphological feature classification and the geomorphological characteristics of Gansu Province were obtained by the window increment analysis, mean-variation analysis, overlay analysis and water box dimension test. [Results] ① According to the mean-variation analysis, the optimal analysis window for DEM classification experiment in Gansu Province was 29×29. ② Based on the classification index system, the geomorphological of Gansu Province could be divided into 13 categories, according to the surface fluctuations, surface cutting degree and topographic position index (TPI) index factor. [Conclusion] Five small watersheds in the study area were selected to test the classification results of the geomorphological features of Gansu Province, and the classification results were in accordance with the actual situation. This paper constructs a classification index system of geomorphological characteristics in Gansu Province, and realizes the classification test of geomorphological characteristics in Gansu Province.

Abstract:[Objective] To explore the applicability of different evaluation methods to kiwi fruit base in Xiuwen County, Guizhou Province, in order to provide scientific basis for selecting cultivation base of kiwi and soil health risk research. [Methods] The pollution situations of the heavy metals in soil were analyzed using the single factor pollution index and Nemero comprehensive index method. Moreover, the potential ecological risk of the heavy metals was evaluated using Hakanson potential ecological risk index and fuzzy mathematics method. [Results] The content of Cu, Ni and Hg in the base A were 1.03, 1.14 and 2.3 times higher than those of the national soil environment quality standard, respectively. The contents of Cu and Hg in the base B were 1.03 and 2.0 times higher and the content of Cu, Ni and Hg in the base C were 1.18, 1.01 and 1.77 times higher than those of the national soil environmental quality standard, respectively. The results by Nemero comprehensive index method showed that the soil of base A belonged to mild pollution, base B and C was non-pollution. The comprehensive pollution indexes of heavy metals in the soil of the three bases were ranked as: base A (1.09) > base C (0.93) > base B (0.91). The principle of potential ecological hazard index showed that the comprehensive index of environmental risk was less than 150 in all the three bases, indicating that the ecological pollution index of eight heavy metals to the environment was light. The comprehensive pollution indexes of soil heavy metal environmental risk in three bases were ranked as: base A (83.61) > base C (78.89) > base B (75.46). The soil in A, B and C base was clean evaluated by fuzzy mathematics method, and the evaluation value of three bases was ranked as : B (97.16) > C (95.44) > A (94.31). [Conclusion] Comprehensive analysis showed that the pollution characteristics of heavy metals in the soil of three bases of kiwi fruit were basically the same, and the main heavy metal pollution was from Cu, Ni, Hg, but the pollution was light, and the soil was in good condition.

Abstract:[Objective] To analyze the characteristics and causes of flood disasters in Hanyuan County, Sichuan Province in Qing Dynasty, in order to provide scientific support for disaster preventions and mitigations. [Methods] The flood disaster data of Hanyuan County in Qing Dynasty was collected. Mathematical statistics analysis methods were used to study the level, frequency, period and causes of the flood disasters in Qing Dynasty. [Results] There were 55 flood disasters with an average frequency of once per 4.87 years in Hanyuan County in the Qing Dynasty. Mild floods, moderate floods, major floods and catastrophic floods accounted for 14.55%, 60.00%, 21.82% and 3.64% of the total flood disasters, respectively, with moderate floods being the main events. Flood disasters showed a fluctuated increasing trend and obvious stages. The periods during 1644-1739 and 1770-1809 were the stage of frequent flood disasters, the periods during 1740-1769 and 1810-1911 were the stage of high-risk flood disasters, and there were five major flood events. The flood disasters in Hanyuan County in Qing Dynasty were marked by a shock period of about 5 years and 10 years, and the flood frequency was high. [Conclusion] There is a high probability of flood disasters in the extreme years of the sunspot, the prosperity period of India summer monsoon and the year of the ENSO events. The rapid of population growth, agricultural reclamation, forest destruction and human-made disorderly development aggravated the frequency and severity of flood disasters.

Abstract:[Objective] To study the relationships between economic development and resource consumption, environmental pollution and eco-environment pressure, in order to reveal the decoupling characteristics of eco-economic system of Fuzhou City, Fujian Province during 2010-2015. [Methods] Ecological footprint model, multi-factor comprehensive evaluation method and improved de-coupling model was used to analyze the eco-environment pressure and economy development status. [Results] ① The additional ecological carrying capacity required to support the regional development increased from 2.89 times in 2010 to 3.37 times in 2015, and the internal contribution rate of the footprint account was ranked as: carbon footprint > cropland > built-up land > forest land > grazing land > fishing grounds. ② The types of the three decoupling coupling elements in the range of every stages were all decoupling type, and there was no critical state or coupling type. [Conclusion] ① The overall eco-environment pressure in Fuzhou City is relatively large, and the dominant pressure in the internal structure of ecological environment is the environmental pollution pressure. ② The development approach in Fuzhou City is still in a sustainable scope, but the decoupling relationship of three decoupled element groups present different temporal evolution feature.

Abstract:[Objective] In order to select the optimal plant varieties for the ecological remediation of crude oil contaminated soil in Eastern Gansu Province, 4 kinds of indigenous plants of this area were selected as the experimental material, and site ecological remediation project was conducted with an experimental period of three months. [Methods] The degradation rate of total petroleum hydrocarbons (TPH), the number of crude-oil degrading bacteria and some plant growth indicators in rizospheric soil of four indigenous plants under different TPH concentrations stress were investigated by the conventional method. [Results] ① The rizospheric soil TPH degradation rate of Medicago sativa and Calendula officinalis was higher than that of leguminous plants(p<0.05), and the chrysanthemum plants were significantly higher than the legumes during severe pollution. ② The increase of TPH concentration could significantly inhibit the root length of compositae plants and the amount of rhizospheric crude-oil degradation bacteria of leguminous plants (p<0.05), while significantly promoted the dry weight of the aboveground part of M. sativa and plant length and dry weight of the underground part of C. officinalis (p<0.05). ③ The results of variance decomposition demonstrated that the interaction effect among the amount of crude-oil degradation bacteria×TPH transfer efficiency and the interaction of plant growth indexes×the amount of crude-oil degradation bacteria were the key factors determining the TPH degradation rate of C. officinalis and Gerbera jamesonii. [Conclusion] The response of 4 indigenous plants to the ecological restoration of crude-oil contaminated soil was varied from species to species, and the compositae plants exhibited better resistance and remediation effect, thus it had certain application potential in Eastern Gansu Province.

Abstract:[Objective] Summary and review of the research status on the preferential flow-induced sliding effects developed by the existence of dominant channels such as joints, fissures and holes in the slope were conducted, in order to draw the attention of scholars to the application of preferential flow theory in the study of slope geological hazards and provide scientific basis for accurate forecasting and early warning of landslides. [Methods] According to the definition and types of preferential flow, the influential factors of preferential flow were analyzed, and the current status of the influence of preferential flow on slope stability, the preferential flow detection technology and the stability evaluation model of slope were reviewed and evaluated emphatically. The developing process of preferential flow-induced landslide effect on loess slope was summarized as four stages, and the typical landslides were taken as examples. Finally, the issues of the preferential flow-induced sliding mechanism were clarified. [Results] The preferential flow widely developed in the dominant seepage channels of the loess slope is a reasonable explanation for slope instability under the condition of limited rainfall depth. However, the theory and application of preferential flow in landslide hazards prediction still need more practical tests. [Conclusion] Slope preferential flow is an important theory in hillslope hydrology, unsaturated soil mechanics, geo-hazards science and other related disciplines. Many achievements have been made over the years. In the future, it is necessary to further study the effect of preferential flow-induced sliding on loess slopes, and strengthen the application of multidisciplinary and new technologies to improve the level on scientific prediction and prevention of geo-hazards.

Abstract:[Objective] The sediment transport path, sediment connectivity and its influencing factors in the small watershed under the condition of extreme rainstorm of the reservoir were explored in order to explore the causes for dam failure and provide basis for the channel flood control. [Methods] Qingshuigou and Shejiagou small watersheds with similar areas and different shapes were selected to investigate the sedimentation in the channel after the rainstorm event occurred in Zizhou County, Shaanxi Province, on 26th July, 2017. The channel was divided into dam-gully section and natural gully section. The area and the shape coefficient of the watersheds, channel gradient and the type and distribution of check dams were used as factors to analyze the differences in sediment connectivity of the channels between the two small watersheds. [Results] Under the extreme rainstorm, all the check dams in Qingshuigou and Shejiagou were opened. The sediment connectivity showed a strong growth trend from the upstream to the downstream in Qingshuigou watershed, while it increased initially and then decreased in Shejiagou watershed. The sediment connectivity of the Qingshuigou watershed was stronger than that of Shejiagou watershed. Additionally, the soil erosion in Qingshuigou watershed was also more serious than that in Shejiagou watershed. Parallel dam system and hybrid dam systems, as well as check dams with horizontal tubes, shafts and drains showed better flood control capacity. [Conclusion] The area, the shape coefficient of watershed and channel gradient all affect the connectivity of channel sediment, while the type and distribution of check dams are the major factors.

Abstract:[Objective] The basic approaches in soil protection in burned forest areas were discussed in order to expound the emerging field of bioengineering applied to soil restoration and stabilization, to soil protection against different types of erosion, in the maintenance of landscape quality and in terms of biodiversity and aesthetic values. [Methods] This study was conducted by reviewing and evaluating the current techniques of bioengineering applied to soil conservation and restoration after forest fires in Spain, setting out some basic principles and describing a few successful examples of applications in various areas affected by forest fires. [Results] The key part of the fundamentals of bioengineering applied to conservation and restoration of soils is based on some traditional principles of soil conservation, especially in regard to the ecological coherence with the specific site of intervention and the use of simple techniques. Also we should not underestimate the role of more recent techniques of civil engineering. These techniques (e.g. use of gabions) are subjected to a process of introducing a greater role for the biological elements (mainly plant materials) which are the main actors in stabilizing the soil in relation to the climate and biophysical characteristics of the area of intervention. Along with living materials, various biomaterials such as plant residues, cut bushes, lignified elements and the wide range of geotextils are also used. These techniques are gathered into four main groups: ① techniques to protect soil, ② stabilization of the ground, ③ combination of reconstruction techniques, and ④ additional stabilization techniques. [Conclusion] Bioengineering applied to soil conservation provides a more environmentally tailored approach that promotes more efficiency in the long term. It also shows advantages in aspects such as its low cost, better adaptation and benefits of multifunctional landscapes. Nevertheless, it includes some important drawbacks such as manpower requirements and the lack of knowledge and availability of suitable plant material, especially in areas of dry climate conditions. Despite these difficulties, bioengineering is an emerging, promising and fast growing applied technique for the new demands on soil protection in the cases of emergency interventions after forest fires impacts.

Abstract:[Objective] The countermeasures for soil salinization control based on the comprehensive utilization of regional resources and management of soil and water resources were discussed in order to develop a new strategy for the management of soil and water resources and provide support for agricultural sustainable development, ecological protection and environmental management in semiarid and arid areas. [Methods] We reviewed the details on the measurements of salt-affected soils worldwide, and summed up the research experiences based on the field investigation in arid areas suffering from soil salinization in Northwest China. A new strategy was proposed by integrated analyzing the main issues existing in saline-alkali treatments. [Results] The main approach of the new developed strategy has two steps: to separate the salts from soil firstly, and then to desalt the salted drainage for irrigation, that would improve the efficiency of soil salinization control measures. It can be abbreviated as "double desalinization approach (DDA)" of soil salinization control measures. The strategy of DDA of soil salinization control measures can be summarized as "reducing regional water loss, leaching of soil salts with less water, intensive desalination of salted soil, and efficient utilization of soil and water resources". Among them, reducing regional water loss is the premise of water resource management and ecological protection in arid area. Leaching of soil salts with less water is the basis to reduce the cost of salt leaching time and water resources. Intensive desalination of salted soil is the key technology to separate the salts and water for reusing. And efficient utilization of water and soil resources is the core economic principle of agricultural development in semiarid and arid areas. [Conclusion] The new strategy of DDA of soil salinization control measures can increase the efficiency of desalination of soil and water by intensive management of soil and water resources in the arid areas. The risks relating to regional natural resources, environment and ecology of this strategy are relatively lower than the traditional methods, and the benefits of management could last for a longer time. The strategy can maintain and improve the regional economic development and the ecological services of ecosystem.