Spatial scale effects on the value of ecosystem services in China's terrestrial area.

Identifying the response characteristics of ecosystem service value (ESV) to changes in spatial scales, known as spatial scale effects, is crucial in guiding the development of corresponding management strategies. This paper examines ESV in China's terrestrial area during the year 2020, revealing the spatial aggregation characteristics of ESV and the trade-off and synergistic relationships of ecosystem services at different spatial scales, ranging from 1 km × 1 km-10 km × 10 km, with a gradient of 1 km. The results indicate: 1) The distribution pattern of ESV in China's terrestrial area is "high in the southeast and low in the northwest." 2) The spatial characteristics of ESV in China's terrestrial area undergo a distinct transition at the 3 km × 3 km scale. In detail, the spatial clustering features show a trend of first rising and then falling with the increase in spatial scale, while the synergistic relationships between different ecosystem services strengthen and the trade-off relationships weaken with the increase of the spatial scale. These findings can inform the formulation of differentiated ecological protection compensation policies and enable cross-area trading of ecological values in China.

Dynamic Evolutionary Analysis of Land Use/Cover and Ecosystem Service Values on Hainan Island.

This study of Hainan Island, based on three periods of land use/cover data from 2008, 2013, and 2017, uses the intensity analysis model and landscape pattern index to portray the dynamic changes of land use on the island and a quantitative analysis of the spatial and temporal evolutionary characteristics of ecosystem service values (ESV) based on the equivalent factor method. At the same time, the response of ESV to landscape pattern changes is explored. The results indicate: (1) From 2008 to 2017, the cultivated land in the coastal areas around Hainan Island continued to expand, which squeezed out forest land and reduced its area. The growth of built-up areas in Haikou City and Sanya City was more dramatic. (2) A weakening trend in the intensity of land use on Hainan Island during the study period. There were significant changes in cultivated land, grassland, and bare land, with forest land, grassland, and water bodies transformed into cultivated land. Built-up areas increased mainly through the occupation of cultivated land, grassland, and water bodies. (3) The fragmentation of landscape patches and the diversity of landscapes on Hainan Island increased, with the distribution of landscape types tending to be balanced. (4) From 2008 to 2017, the overall ESV of the island showed an initial decrease before increasing; the main spatial distribution characteristic of the ESV was "high in the central and low in the surroundings". (5) The mean patch area, the Shannon diversity index, and the largest patch index showed clear positive correlations to ESV.

[Impact of provincial infrastructure investment on the vulnerability of social-ecological system in China]. / æˆ‘å›½çœåŸŸåŸºç¡€è®¾æ–½æŠ•å ¥å¯¹ç¤¾ä¼š-生态系统脆弱性的影响.

The impact of infrastructure investment on social-economic system or ecological system has been widely discussed, yet, the overall impact of infrastructure investment on social-ecological system (SES) is still unknown. This study summarized the impact mechanism of infrastructure investment on social ecosystem vulnerability. We first sorted out the impact mechanism of infrastructure investment on SES vulnerability, and then empirically analyzed the effect of provincial infrastructure investment on SES vulnerability by using spatial autocorrelation and spatial econometric models on the basis of accounting provincial per capita infrastructure capital stock and comprehensive evaluation of SES vulnerability. The results showed that the infrastructure capital stock per capita at provincial level increased significantly during 2004-2017, with a spatial pattern that the north was higher than the south and the east/west was higher than the middle in China. The provincial SES vulnerability was improved, with spatial distribution characteristics of gradually getting worse from east to west in China. There was positive spatial correlation between provincial infrastructure investment and SES vulnerability, with aggregation distribution characteristics. There was inverted U-shaped relationship between infrastructure investment and SES vulnerability in China, that was, the appropriate investment of infrastructure at early could decrease SES vulnerability, while over-investment would increase it. Our results revealed the overall impact mechanism and dynamic characteristics of infrastructure investment on SES vulnerability, and could provide theoretical and policy-making support for the coordination of infrastructure construction and SES vulnerability governance at the macro level for China.

Simulating Land-Use Changes and Predicting Maize Potential Yields in Northeast China for 2050.

Crop potential yields in cropland are the essential reflection of the utilization of cropland resources. The changes of the quantity, quality, and spatial distribution of cropland will directly affect the crop potential yields, so it is very crucial to simulate future cropland distribution and predict crop potential yields to ensure the future food security. In the present study, the Cellular Automata (CA)-Markov model was employed to simulate land-use changes in Northeast China during 2015-2050. Then, the Global Agro-ecological Zones (GAEZ) model was used to predict maize potential yields in Northeast China in 2050, and the spatio-temporal changes of maize potential yields during 2015-2050 were explored. The results were the following. (1) The woodland and grassland decreased by 5.13 million ha and 1.74 million ha respectively in Northeast China from 2015 to 2050, which were mainly converted into unused land. Most of the dryland was converted to paddy field and built-up land. (2) In 2050, the total maize potential production and average potential yield in Northeast China were 218.09 million tonnes and 6880.59 kg/ha. Thirteen prefecture-level cities had maize potential production of more than 7 million tonnes, and 11 cities had maize potential yields of more than 8000 kg/ha. (3) During 2015-2050, the total maize potential production and average yield decreased by around 23 million tonnes and 700 kg/ha in Northeast China, respectively. (4) The maize potential production increased in 15 cities located in the plain areas over the 35 years. The potential yields increased in only nine cities, which were mainly located in the Sanjiang Plain and the southeastern regions. The results highlight the importance of coping with the future land-use changes actively, maintaining the balance of farmland occupation and compensation, improving the cropland quality, and ensuring food security in Northeast China.