Is land degradation worsening in Northern China? Quantitative evidence and enlightenment from satellites

Abstract

Land degradation has become an urgent environmental issue globally. The complexity of land degradation hinders its quantification and monitoring, which is needed to realize the sustainable development of land resources. This study constructed a comprehensive index—land degradation status index (LDSI), which integrates in fractional vegetation cover (FVC), net primary productivity (NPP), albedo, and modified temperature vegetation drought index (MTVDI) based on spatial principal component analysis (SPCA). Land degradation was then identified by the dynamics of land degradation status during 2001–2018. This study investigated the spatio‐temporal process and driving mechanism of land degradation in Northern China. The result indicates that: (1) LDSI had a better monitoring performance compared with normalized difference vegetation index (NDVI), (2) although some degraded land had been effectively rehabilitated (17.11%), a highly clustered spatial distribution of land degradation status remained, challenging to break, (3) localized land degradation had expanded (1.063%), mainly in semiarid (0.481%), dry sub‐humid (0.289%), and humid (0.187%) regions, and (4) differences in climate, environmental backgrounds, and human activities were driven land degradation status and process. This study also assessed the effectiveness of ecological projects implemented by the Chinese government. The in‐depth understanding of the change regularity and influencing mechanism in land degradation status and process can provide a scientific basis for formulating ecological policies based on local conditions.

UAV‐SfM‐based field quantification of barchan dune celerity and morphodynamics in Gonghe Basin

“…China is one of the countries seriously affected by desertification, accounting for 17.93% of its land area (Xu & Zhang, 2021). The research results show that the risk of desertification in China will increase over time by the end of this century (Huang et al, 2020), local land degradation was expanding in northern China, mainly in semi‐arid areas (Guo et al, 2023). The activation and stabilization process of sand dunes is closely related to climate change, environmental changes and human activities, and has been widely concerned by the academic community.…”

Mapping Main Grain Crops and Change Analysis in the West Liaohe River Basin with Limited Samples Based on Google Earth Engine

“…Crop planting structure refers to the types, area, and distribution of crops, reflecting the utilization of agricultural resources within a specific region [1], which is the prerequisite for crop area measurement [2][3][4], yield estimation, and growth monitoring [5]. However, land degradation [6], extreme weather events [7], and rapid urbanization [8] pose severe threats and challenges to agricultural production activities [9]. Extracting crop planting information accurately can provide crucial decision-making information for both government authorities and farmers [10], which can strongly support agricultural production, policy formulation, and ecological environment protection.…”