Abstract:Abstract: [Objective]Research on carbon emission effect of“Production-living-Ecological” function change can provide reference for territorial and spatial planning under the background of “carbon peaking and carbon neutrality goals”.[Methods]The research applied the methods including evaluation assignment method, energy consumption method and geographical weighted regression model to reveal the spatial-temporal evolution characteristics of the "production-living-ecology" functions and its effect the carbon emission in Liaoning Province from 2005 to 2020. [Results]① the spatial distribution pattern of the "production-living-ecology" functions in Liaoning Province had not changed much from 2005 to 2020. Most of the areas were dominated by production and ecological functions, the living function areas were obviously expanded, and the spatial difference mainly occurs between the central urban and the surrounding areas; ② From 2005 to 2013, the carbon emissions of counties in Liaoning Province increased rapidly, and from 2013 to 2020, the growth rate was slower but its spatial difference became more obvious. The high carbon emissions were significantly concentrated in Shenyang and Dalian cities；③ At the aspects of spatial pattern and quantitive change, the overall correlation between the "production-living-ecology" function and carbon emission is strong, meanwhile, the spatial differences were obvious and its influenced factors were complex. [Conclusion] Under the constraints of natural conditions and guided by their social and economic development needs, counties in Liaoning province need to clarify the main functions of the land and promote the regional cooperation on the basis of their own advantages and resource endowment, in order to realize of carbon emission reduction of the whole region.

Abstract:[Objective] Under the background of “double carbon”, exploring the carbon emission efficiency of grain production in North China and quantifying its spatial differentiation and dynamic evolution, and analyzing the current situation of carbon emission efficiency of grain production in North China are conducive to promoting green and low-carbon grain production in North China. [Method] The carbon emission coefficient method and the three-stage super-efficiency SBM model were used to measure the carbon emission and carbon emission efficiency of grain production in North China from 2011 to 2020, and then the Theil index and kernel density estimation were used to explore the regional differences and dynamic evolution of carbon emission efficiency of grain production. [Result] ①During the study period, the carbon emissions of grain production in North China showed an “M” type fluctuation downward trend, but the decline was slow. Among them, the use of chemical fertilizers is the main cause of grain carbon emissions. ②The carbon emission efficiency of grain production in North China showed an evolution trend of decreasing first and then increasing. The average efficiency of the first stage was 0.59. Excluding the influence of environmental variables and random errors on the efficiency value, the average efficiency of the third stage was 0.48, which was 18.6 % lower than the efficiency value of the first stage. Chuzhou, Zhumadian, Dezhou and other places have higher efficiency values, while Huangshan, Weihai and other places have lower efficiency values. ③The spatial difference of carbon emission efficiency of grain production is on the rise, and the regional difference is the main factor affecting the overall difference, among which the difference among cities in Henan Province is the most significant. ④During the investigation period of the sample, the kernel density function. changed from “single peak” to “double peak”, the main peak showed a fluctuating rise and a slight right shift trend, and the side peak uplift was small. [Conclusion] The overall level of carbon emission efficiency of grain production in North China is low, and there are obvious spatial differentiation characteristics. In the future, all regions should reduce the redundancy of material input such as chemical fertilizer, and adopt the strategy of “counterpart assistance ” to promote the benign interaction of grain production technology, so as to narrow the regional differences in carbon emission efficiency of grain production among regions.

Abstract:[Objective] To investigate the influence of land use change patterns on the spatial distribution of carbon sinks in the Inner Mongolia section of the Yellow River Basin, and to identify the main driving factors behind, so as to provide a basis for ecological spatial development directions and sink enhancement policies in the study area.[Methods] Taking the Inner Mongolia section of the Yellow River Basin as an example, we used the InVEST-FLUS model to analyze the changes of carbon sink capacity in each period based on land use data in 2000, 2010 and 2020, and simulated the patterns of carbon stock changes in 2040 under three different scenarios of natural development, ecological conservation and agricultural priority, and identified the factors behind the differences in the spatial distribution of carbon sinks with the help of geographic probes. The main driving factors behind the differences in spatial distribution of carbon sinks are identified with the help of geographic probes. [Results]① From 2000 to 2020, carbon storage in the Mongolian section of the Yellow River Basin increased first and then decreased, with an overall increase of 8.63×106t, in which subsurface biological carbon storage increased by 3.91×106t and soil carbon storage increased by 2.28×106t. ②Carbon storage continued to decrease by 3.92×106t in the future natural development scenario, but increased by 22.1×106t in the ecological protection scenario, which was higher than that of 4.99×106t in the agricultural priority scenario. Soil carbon storage was the key to the incremental difference. ③The unbalanced distribution of annual mean rainfall and annual mean temperature is the main factor that causes the difference of various carbon pools in the Mongolian section of the Yellow River Basin. [Conclusion] Reasonable ecological protection policies are more in line with the future requirements of urban intensification and ecological high-quality development, and in the future, we should pay attention to desertification prevention and control and promote forest and grassland construction, so as to provide a guarantee for improving the regional ecological security pattern and sink enhancement policies.

Abstract:[Objective] To analyze the temporal and spatial characteristics of net carbon emissions from agriculture at the county scale in Fujian Province, with a view to providing a reference basis for the formulation of carbon emission reduction countermeasures in Fujian Province and other provinces and municipalities. [Methods] We constructed an accounting inventory of agricultural carbon emissions based on 12 carbon sources in plantation and livestock industries, and measured the total agricultural carbon emissions by using the carbon emission factor method; selected seven major crops to calculate the carbon uptake by combining with the agricultural characteristics of Fujian Province; and analyzed the spatial and temporal characteristics of the net agricultural carbon emissions in Fujian Province from 2001 to 2020 by using the exploratory spatial analysis method. [Results] ① During the study period, the net carbon emissions showed an inverted "V" trend of first increasing and then decreasing. In terms of carbon sources, carbon emissions from agricultural land use accounted for a larger proportion; in terms of carbon sinks, rice, vegetables and sugarcane contributed more to carbon sequestration. The intensity of agricultural carbon emissions in most counties (cities) showes a decreasing trend, but the average annual decline is small. ② There is a significant global spatial positive correlation of carbon emissions in counties in Fujian Province, showing spatial agglomeration characteristics, and the agglomeration pattern is dominated by high-high and low-low agglomeration. The spatial distribution pattern of the intensity of agricultural carbon emissions changes considerably, with an overall decreasing trend, in which about half of the counties (cities) are in the lower intensity zone. ③ The spatial class distribution pattern of counties (cities) in Fujian Province from 2001 to 2020 has changed to a certain extent, with an increase in the number of medium-emission zones and medium-low-emission zones, and a decrease in the number of high-emission zones, medium-high-emission zones and low-emission zones, and the polarization has been alleviated. [Conclusion] In recent years, most counties inFujian Province have shown a decreasing trend in agricultural carbon emissions and carbon emission intensity, and carbon emission reduction has achieved certain results, but the decline is not large, the future should also be from the policy incentives, optimization of industrial structure and other aspects of the measures taken to strengthen the effect of emission reduction, and to promote the transformation of agriculture low-carbon.

Abstract:[Objective] The succession of vegetation community in the process of grassland shrub encroachment will affect the soil organic carbon pool, and the active components of soil organic carbon ( SOC ) can quickly reflect the change of soil organic carbon pool. By exploring the effect of shrub encroachment on the active components of SOC in alpine meadow, it is expected to provide data support for the study of soil organic carbon pool change and carbon sequestration in grassland of Qinghai-Tibet Plateau under the background of global climate change. [Methods] Taking the Caragana erinacea shrub meadow in the Qinghai-Tibet Plateau as the research object, the changes of soil physical and chemical properties, carbon cycle enzyme activities and SOC active components in 0-10 cm, 10-20 cm and 20-40 cm at different shrub encroachment stages ( non-shrub, moderate-shrub and severe-shrub meadow ) were analyzed. [Results] ① The soil water content ( SWC ) in the 0-20 cm soil layer decreased significantly, and the SOC content in each soil layer was the highest in the heavy shrub meadow, and the soil pH increased significantly in the moderate shrub meadow. ② The soil amylase activity ( SAA ) of moderate shrub meadow was significantly lower than that of non-shrub meadow, and the soil sucrase activity ( SSA ) of 10-40 cm soil layer was also significantly lower. SSA was significantly stronger than that of non-shrub meadow in the severe shrub stage. ③Compared with non-shrub meadow, the content of readily oxidizable organic carbon ( ROOC ) in 0-10 cm, 10-20 cm and 20-40 cm of moderate shrub meadow decreased by 16.79 %, 21.73 % and 31.11 %, respectively, and the content of dissolved organic carbon ( DOC ) and microbial biomass carbon ( MBC ) in 0-10 cm soil also decreased significantly. The contents of particulate organic carbon ( POC ) and ROOC in 0-10 cm soil increased significantly by 24.37 % and 29.54 %, respectively. The contents of MBC and DOC in 10-20 cm soil increased significantly by 12.96 % and 10.38 %, respectively. The contents of MBC and DOC in 20-40 cm soil increased significantly by 57.62 % and 22.10 %, respectively. ④ Soil organic carbon active components were significantly positively correlated with TN, SWC, SOC and carbon cycle enzyme activity, and ROOC was significantly negatively correlated with pH. [Conclusion] The content of soil organic carbon active components in the early stage of Caragana erinacea shrub encroachment in the study area decreased, while the soil organic carbon and its active components were accumulated in the later stage of shrub encroachment, which may have a positive effect on the accumulation of soil organic carbon and the improvement of soil quality in this area.

Abstract:[Objective] The desertification and its driving factors in Gansu Province was analyzed to provide a scientific basis for the comprehensive prevention and control of desertification and the promotion of ecological projects such as the "Three Norths". [Methods] Trend analysis and spatial autocorrelation analysis were used to characterize the spatial and temporal distribution of desertification in Gansu Province from 2000 to 2022, and geographically and temporally weighted regression was used to analyze the influencing factors. [Results] ○1The overall desertification in Gansu Province presented the characteristics of "desertification in the northwest and greenness in the southeast". The north-west region, which was affected by both wind erosion and salinization, had the most serious desertification, which gradually decreased towards the south-east; the central region, which was affected by soil and water loss, still had a serious degree of desertification; while the south region had a less serious degree of desertification. In terms of time, the degree of desertification in Gansu Province gradually improved during the 23-year period, and the degree of improvement was stronger in the southern region than in the northern region. ○2In terms of spatial autocorrelation, desertification in Gansu Province was mainly characterized by aggregation, i.e., the degree of desertification showed obvious positive spatial correlation. ○3Increased precipitation was most beneficial in mitigating desertification and had a greater impact in the northwest than in the southeast, while wind speed and population exacerbated desertification, and desertification was exacerbated by warmer temperatures in the southwest and vice versa in the rest of the region. [Conclusion] From 2000 to 2022, desertification in Gansu Province showed an improving trend, while desertification in the northwestern part of the province was still serious, and there was obvious spatial and temporal heterogeneity in the drivers of desertification in Gansu Province, and the most important factor affecting desertification was precipitation.

Abstract:[Objective]To carry out research on the evaluation of the ecosystem health level of the Gansu section of the Yellow River Basin, and to provide theoretical reference and decision-making basis for the ecological protection and high-quality development of the basin.[Methods] Based on the 2011-2021 panel data, the PSR model was used to construct an ecosystem health evaluation index system for the Gansu section of the Yellow River Basin, the entropy value method and the comprehensive index method were used to comprehensively evaluate the ecosystem health level, and the GM-ARIMA model was used to predict the ecosystem health changes in the next ten years.［Results］(1) From 2011 to 2021, the overall ecosystem health index of each city and state shows an upward trend, with Gannan ecosystem health in the Gannan Yellow River Important Water Supply Ecological Functional Area, in which Gannan ecosystem health is ranked as "inferior", Linxia ecosystem health from "inferior" to "poor", Loess Plateau Area, in which Lanzhou ecosystem health is ranked as "medium" to "good", Tianshui, Dingxi, and Pingliang ecosystem health is from "inferior" to "poor", Baiyin and Qingyang ecosystem health is in the "inferior" range, and Wuwei, a wind-sand comprehensive prevention and control area, has ecosystem health ranked as "inferior"; (2) The projected results of the ecosystem composite index for the period 2022-2031 show an increasing trend, but there is no significant change in the ecosystem health rating.[Conclusion] The overall level of ecosystem health in the Gansu section of the Yellow River Basin is not high, and current ecological protection and environmental improvement measures have not yet fully resolved the challenges facing the region''s ecosystem, which will need to be further strengthened in the future by enhancing regulation and management to improve the health of the region''s ecosystems.

Abstract:[Objective] Analyzing the spatial-temporal evolution and influencing factors of carbon emissions in Qingdao City is of great significance for ecological protection and high-quality development.[Methods] Based on the land use data, nighttime light data, and social and economic data of Qingdao city from 2000 to 2020, carbon emissions from land use were calculated. By constructing a fitting model between carbon emissions and nighttime light values, the spatial distribution difference and trend of carbon emissions of different land use types in Qingdao city were revealed. The decoupling status between carbon emissions and economic development in Qingdao city was analyzed through the Tapio decoupling model. The contribution degree of various influencing factors of land use carbon emissions was analyzed by using Kaya decomposition and LMDI models. [Results] ①The net carbon emissions from land use in Qingdao city generally showed an increasing trend from 2000 to 2020. From 13,096,400 tons in 2000 to 36.4820 million tons in 2020, an increase of nearly 1.79 times;②The overall carbon emissions in Qingdao city presented a spatial distribution pattern of "high in the middle and low around", and industrial energy consumption was the main source of carbon emissions from construction land, with high carbon emission areas mainly concentrated in the Jiaozhou Bay area;③The relationship between economic development and carbon emissions in Qingdao city has undergone a transition from "expansion link to weak decoupling to strong decoupling";④The factors that promote the growth of carbon emissions in Qingdao are population size and economic effect, and the factors that inhibit the growth of carbon emissions in Qingdao are energy structure and energy intensity. [Conclusion] In the future, it is necessary to further adjust the industrial structure, accelerate the development of a low-carbon economy, and reduce carbon emissions from the source through measures such as technological innovation and energy structure adjustment.

Abstract:[Objective]Within the framework of the dual carbon target vision, addressing the scale effects of forest land changes and quantifying the carbon sequestration benefits at multiple watershed levels not only introduce a fresh perspective into forest land research but also aid in cording and optimizing the forest land pattern. That holds great significance in enhancing future regional carbon sequestration potential.[Methods]Focusing on Chongqing as the study area, we analyzed the spatiotemporal dynamic changes in forest land and carbon storage from 2000 to 2030 at the multi-watershed scale, utilizing PLUS model, landscape pattern indices, biomass expansion factor method and grey correlation degree. Furthermore, we explored the correlation between forest land pattern changes and carbon storage under natural development scenarios.[Results](1)Between 2000 and 2020,the forest area increased by 3404.55 km2,primarily due to the conversion of cultivated land. The forest landscape pattern in the first-grade watershed showed a tendency towards clustering and regularity, with a relatively reduced degree of fragmentation. There were distinct differences in the historical laws and future trends of forest landscape pattern changes in the secondary watershed’s “district and group”.(2)In the initial two decades, the carbon storage of forest land exhibited an increasing-decreasing trend, resulting in an overall increase. The Dongting Lake system in the first level basin witnessed the highest increase in carbon storage, and the high-value area of carbon storage increment in the seconde level basin shifted from north to south.(3)The total carbon storage is predicted to increase by 2030 which is strongly correlated with the irregular index. The scale effect leads to the spatial heterogeneity of landscape pattern change and the correlation degree between landscape pattern index and carbon storage in the primary and secondary basins.[Conclusion]The research outcome contribute to understanding the patterns of forest land changes from a cross-watershed scale perspective. This, in turn, provides a scientific foundation for the Ministry of Natural Resource or relevant forestry departments to formulate effective utilization and protection policies for forest land resources at different scales, It also supports the sustainable development of Chongqing, enhances carbon sink efficiency, and facilitates the achievement of carbon neutrality goals.

Abstract:[Objective] To In order to better monitor and evaluate the ecological quality of hilly areas, it is necessary to construct a accurate remote sensing ecological index of middle and high vegetation areas, and explore the influencing factors of its ecological quality, so as to provide scientific support for the balance between development and ecology in Taojiang County. [Method] To address the saturation issue of the Normalized Difference Vegetation Index (NDVI) in densely vegetated areas, this study introduces the kernel Normalized Difference Vegetation Index (kNDVI) and integrates it with humidity, dryness, and heat factors to formulate a Modified Remote Sensing Ecology Index (MRSEI). Utilizing this index, the ecological environment quality and its temporal variation in Taojiang County from 2000 to 2021 were quantified. Additionally, a parameter optimized geographic detector model was employed to analyze the driving forces of six influencing factors, including vegetation coverage, precipitation, temperature, land use, altitude, and population density. [Result] (1) Compared with the RSEI model, the MRSEI model can effectively address the issue of NDVI saturation in areas with high vegetation cover, enabling a more precise monitoring of the ecological environment in Taojiang County; (2) The average RSEI values for the five periods from 2000 to 2021 in the study area were 0.77, 0.84, 0.83, 0.75 and 0.79, respectively, indicating a satisfactory performance in ecological environment quality with a trend of improvement-deterioration-improvement; (3) From the analysis of the factors influencing ecological environment quality, land use emerges as a key factor determinant in the study area. In the factor interactive detection analysis, the interaction between land use and elevation were strongest. [Conclusion] In summary, variation of the ecological environment quality in Taojiang County is primarily influenced by a combination of natural and anthropogenic factors. The research results can provide technical reference for carrying out effective ecological environment protection and restoration measures in Taojiang County.