Optimizing the spatial pattern of land use in a prominent grain-producing area: A sustainable development perspective

Optimization of Chinese land spatial pattern in the transformation process of resource-based cities: a case study in Tongling City, China

Optimizing the spatial layout of the national territory is crucial for realizing the transformation and development of resource-oriented cities in the context of high-quality development in the new period. This paper takes Tongling City as a case study, based on the analysis of the historical development foundation, then uses the SD-FLUS comprehensive model to carry out a systematic analysis of the transformation in five dimensions of economy, society, population, science and technology, resources and environment, and discusses the optimization of spatial pattern under the contextual simulation. The conclusions are as follows: ① The hierarchical framework of "system-indicator-element" is not only internally interconnected, but also inextricably linked with the relationship between the various categories of the land use system. ② Decrease of cropland, forest, water, grassland, and barren decreases from the economic development, social progress, and comprehensive development, and there is a small increase in the area under the scenario of resource and environmental protection, and the direction of the change of the impervious is in the opposite direction. ③ Cultivated land is retained in situ and concentrated to a small extent, forested land is reduced to a small extent while the status quo is maintained, and the Yangtze River water system will be retained and protected to a large extent, but part of the waters of Zongyang County will give way to the expansion of construction land under the development objectives of the new county. Building land will be expanded and extended to the northeast in the original site area, while the southwest corner of the original county center will be expanded to some extent in Zongyang County to promote the county's economic development.

Spatial-temporal evolution of production-living-ecological space and layout optimization strategy in eco-sensitive areas: a case study of typical area on the Qinghai-Tibetan Plateau, China

To achieve sustainable development goals and to solve environmental problems, land resources in eco-sensitive areas should be used and optimized. Qinghai, which is an important eco-sensitive area in China, represents a typical ecological vulnerable region on the Qinghai-Tibetan Plateau. Using land use/cover data for 2000, 2010 and 2020, this study applied a series of quantitative methods to analyze the spatial pattern and structure of the production-living-ecological space (PLES) in Qinghai. The results indicated that the spatial pattern of the PLES in Qinghai was stable over time, but the spatial distribution was very different. The structure of the PLES in Qinghai was stable, and the proportion of each space from high to low was ecological (81.01%), production (18.13%) and living (0.86%). We found that the proportion of ecological space in both the Qilian Mountains and the Three River Headwaters Region was lower than the rest of the study area, except for the Yellow River-Huangshui River Valley. Our study objectively and credibly presented the characteristics of the PLES in an important eco-sensitive area in China. This study further formulated targeted policy suggestions to provide a basis for regional sustainable development, ecological environment protection, and land and space optimization in Qinghai.

Ecological function zoning based on ecosystem service bundles and trade-offs: a study of Dongjiang Lake Basin, China

Although the research framework of ecological function zoning is complex and diverse, there are not many spatially continuous zoning results, which can be effectively applied to watershed management practices. Ecosystem service bundles and trade-offs can identify interactions among multiple ecosystem services, and achieve better social-ecosystem management when applying to ecological function zoning. Taking the Dongjiang Lake Basin, China, as research area, the study used the InVEST model to investigate the trade-offs and synergies of ecosystem services at township and grid scales, respectively. Then, the study conducted ecological function zoning based on the bundles and trade-off intensity among ecosystem services. The results showed that food production showed extremely significant trade-offs with other services in the two scales, in which the trade-off intensity between food production and water purification was the largest, and the water areas were the hotspots of trade-off intensity. Based on the ecosystem service bundles at the township, combined with the trade-off intensity, the watershed was finally divided into four ecological functional zones, namely, agricultural product supply area (southern part in the study area), economic forestry area (northeast regions in the study area), water supply area (western areas of the study area), and forest conservation area (northern areas in the study area), accounting for 29.27%, 14.63%, 17.07%, and 39.03%, respectively. The study contributed to the ecological function maintenance and sustainable development in Dongjiang Lake Basin and provided an important reference in ecological zoning.

Integrating Landscape Ecological Risks and Ecosystem Service Values into the Ecological Security Pattern Identification of Wuhan Urban Agglomeration

Urban agglomerations are the main form of China's future promotion of new urbanization development. Nevertheless, their accelerated expansion and development are increasingly threatening the security of regional ecosystems. The identification and optimization of ecological safety patterns (ESPs) is the fundamental spatial way to guarantee the ecological safety of urban circles and realize the sustainable development of the socio-economic and ecological environment. Nevertheless, from the perspective of urban green, low-carbon, and ecological restoration, regional safety evaluation still lacks a complete framework integrating ecological elements and social and natural indicators. Moreover, the evaluation method of ESPs also has a lack of judgment on the long-term change dynamics of regional landscape ecological risks and ecosystem service values. Thus, we proposed a new regional ecological security evaluation system based on ecosystem service value (ESV) and landscape ecological risk (LER), using the Wuhan urban agglomeration (WUA) as the research object. This study analyzed LER and ESV's spatial and temporal changes over nearly 40 years from 1980 to 2020. LER and LSV were used as ecological elements combined with natural and human-social elements to jointly model the resistance surface of the landscape pattern. Applying the minimum cumulative resistance model (MCR), we identified green ecological corridors, constructed the ESPs of WUA, and proposed optimization measures. Our results show that: (1) The proportion of higher- and high-ecological-risk areas in WUA has decreased from 19.30% to 13.51% over the past 40 years. Over time, a "low-high-low" hierarchical distribution characteristic centered on Wuhan city was gradually formed in the east, south, and north; the total value of ecosystem services increased from CNY1110.998 billion to CNY1160.698 billion. The ESV was higher in the northeastern, southern, and central parts of the area. (2) This study selected 30 ecological source areas with a total area of about 14,374 km2 and constructed and identified 24 ecological corridors and 42 ecological nodes, forming a multi-level ecological network optimization pattern with intertwined points, lines, and surfaces, increasing the connectivity of the ecological network and improving the ecological security level of the study area to a large extent, which is of great significance to promote the ecological priority and green-rise strategy of WUA and the high-quality development path of the green ecological shelter.

Coupling coordination analysis and spatiotemporal heterogeneity of the agricultural eco-economic system in the main grain-producing areas of Jilin Province

Jilin is a major agricultural province and an important grain-producing area in China. Under the requirements of ensuring national grain security and green development for regional agriculture, the coordinated development of agricultural ecology and the economy in grain-producing areas is a crucial issue. Sixteen major grain-producing counties in Jilin Province were selected and a comprehensive evaluation index of the agricultural eco-economic system was established to analyze the relationship between the two subsystems in the main grain-producing areas from 2004 to 2018. The study aimed to determine the relationship between agricultural ecology and the economy in the grain-producing areas of Jilin and how to promote high-quality development of the agricultural system according to the local conditions. The results showed that (1) the coupling coordination degree (CCD) in the main grain-producing areas was steadily improved during the study period and was closely related to the impact of agricultural policies; (2) the CCD of the central area was less than that of the west, mainly because the agricultural ecological development lagged far behind the economy; (3) agricultural modernization, environmental protection, and increasing grain added value were important ways to promote CCD development in the grain-producing areas. This study emphasized the importance of the coordinated development of agricultural ecology and the economy and provides an important reference for formulating regionally differentiated development strategies and achieving sustainable agriculture in main grain-producing areas.

Optimizing the Use of Cultivated Land in China's Main Grain-Producing Areas from the Dual Perspective of Ecological Security and Leading-Function Zoning

In order to achieve the coordinated development of ecological protection and cultivated land use, ecological security and cultivated land use functions (CLUFs) in the study area were evaluated by constructing a comprehensive evaluation index system. The leading CLUFs were measured, and it was determined to use the normalized revealed comparative advantage (NRCA) index. The spatial superposition analysis of the ecological security level and the leading CLUFs was carried out to obtain the zoning of the coordinated development of ecological security and cultivated land use, and differentiated utilization strategies were proposed for different zones. The results of this study showed the following: (1) The ecological security level of cultivated land in Yuanyang County can be divided into high, medium, and low security levels, accounting for 30.68%, 43.42%, and 25.9% of the total cultivated land area, respectively. The overall ecological security level is high. (2) The current cultivated land use mainly has a production function, accounting for 38.39% of the total cultivated land area, the leading CLUFs that are 34.16% of the cultivated land are the ecological function, and 27.45% of the cultivated land is the living function. (3) The spatial superposition analysis of the ecological security level and leading CLUFs yielded four zones of cultivated land use enhancement, including a production core zone, and different control strategies were proposed for the different zones. These strategies may help to fully realize the multifunctionality of the cultivated land without compromising ecological protection. Implementing differentiated protection for cultivated land in different use zones can achieve the coordinated development of ecological protection and cultivated land use, thus promoting the sustainable use of cultivated land resources.

Evaluation of the Ecological Environment Quality of the Kuye River Source Basin Using the Remote Sensing Ecological Index

Landsat remote sensing images obtained from 2000, 2005, 2010, 2015, and 2020 were analyzed. The normalized vegetation index (NDVI), moisture index (WET), land surface temperature (LST), and normalized building-soil index (NDBSI) were extracted based on the four aspects of greenness, humidity, heat, and dryness. The Remote Sensing Ecological Index (RSEI) was calculated using principal component analysis to quantitatively analyze and dynamically monitor and evaluate the ecological environment changes in the Kuye River Basin over the past 20 years. From the perspective of spatial and temporal distribution, the ecological and environmental quality of Kuye River Basin had a downward trend from 2000 to 2020. The overall RSEI grade was medium or poor, and the average RSEI decreased. The proportion of excellent and good grade watershed areas decreased, whereas that of medium, low, and poor grade watershed areas increased over the study period. Spatially, RSEI decreased gradually from southeast to northwest. The degraded areas were mainly distributed in urban areas with frequent human activities. Conversely, the superior eco-environmental quality areas were mainly distributed in eastern sections of the watershed. Compared with 2000, the eco-environmental quality of the Yulin urban area and Shenmu County in the southern section of the watershed are worsening.