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We investigate the eco-environmental effects and the driving factors of transforming the production–living–ecological space (PLES) land use function and offer a scientific foundation for developing regional territorial area and environmental preservation. Eco-environment quality index and ecological contribution ratio are used to analyze the spatial–temporal evolution characteristics and eco-environment effects of land use transformation in the Yangtze River Delta Urban Agglomeration (YRDUA) over the three time periods of 2000, 2010, and 2020, and the geographic detectors are used to analyze the factors that influence the spatial difference of eco-environment quality (EEQ). The findings indicate the following: (1) The land use transformation of YRDUA is primarily shown in the shrinkage of the production land area, the stability of ecological land, and the rapid increase of living land. The area of ecological land, such as water, forest, and pasture, has remained relatively steady from the perspective of secondary land types. In contrast, the area of urban and rural living land has significantly increased. (2) Most land use environment comprises the lower-value zone, accounting for about 50%. The area of the low-value zone has continued to rise owing to the rapid urban and rural living land development, tending to continuous growth. (3) Both the ecological improvement and degradation trends are present simultaneously, although the ecological improvement trend is less prominent than the environmental degradation trend. The primary factor is improving the eco-environment by transforming agricultural production land into forest, water, and ecological pasture land. The degradation of the regional EEQ is mostly due to the occupation of agricultural production land by urban and rural living land. (4) Considering natural elements such as altitude, precipitation, and slope, the extent of land use impacts the EEQ. The combination of several factors has changed the EEQ of the YRDUA. The effect of any two elements is stronger than that of a single factor. [ABSTRACT FROM AUTHOR]

The Grain for Green Project (GGP) has influenced Shaanxi Province's land-use pattern, resulting in a shift in ecosystem service value (ESV). Exploring the spatial and temporal evolution of the pattern of land use and ESV in Shaanxi Province, before and after the project's implementation, can give a theoretical foundation for regional land-use planning. For this study, we used the transfer matrix and the value equivalent approaches to investigate the influence of project implementation on the spatial distribution and evolution of patterns of land use and ESV in Shaanxi Province based on four periods of land-use data from 1990 to 2020. The results suggest the following: (1) Farmland, forestland, and grassland were the most common land-types in Shaanxi Province. Farmland, forestland, and grassland in Shaanxi Province were all altered dramatically over the research period due to the GGP. Farmland was turned mostly into forestland and grassland, and forestland and grassland areas progressively grew. (2) The ESVs in Shaanxi Province were USD 3802.82, 3814.90, 3836.20, and 3806.50 billion in 1990, 2000, 2010, and 2020, respectively. The most value was supplied by hydrological management, while water resources provided the lowest value. Forestland and grassland were the most valuable land-types in high-value locations, whereas built-up land was the most valuable land-type in low-value areas. (3) While the GGP has increased the ESV of forestland and grassland, it has harmed the acreage of other land-types, resulting in a decline in the total ESV in Shaanxi Province. [ABSTRACT FROM AUTHOR]

Exploring soil water dynamics under different land use types is important for water resource management and vegetation restoration in the Loess Plateau. In this study, we investigated the hydrogen and oxygen isotopic compositions of soil water from four different land use types to explore the mechanism of soil water movement and transformation and analyse the influence of land use. The results show that the range of stable isotopes (δD and δ18O) in soil water was smaller than that in precipitation. Values for δD and δ18O in soil water showed relatively similar temporal variation, heavy isotopes were enriched in the soil water in July and depleted in October. Stable isotope values in shallow (<100 cm depth) soil water and deep (>200 cm depth) soil water were low. The δD and δ18O values in woodlands decreased gradually with increasing depth. Across the four land use types, the maximum variation in δD and δ18O was in the shallow depth of the soil profile. Groundwater was recharged mainly from precipitation and then from soil water. The ratio of groundwater recharge by soil water under different land use types followed this rank order: woodland (35.70%) > grassland (31.14%) > shrubland (29.47%) > cropland (29.18%). Matrix flow and preferential flow coexisted during infiltration, and the occurrence of preferential flow was related to the land use type. The main reason for the variation in isotopic composition in soil water is the difference in soil evaporation, which is influenced by different vegetation cover. Owing to the difference in soil evaporation and fractionation, precipitation on cropland, shrubland, and grassland can recharge more soil water than on woodland. [ABSTRACT FROM AUTHOR]