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Feng S, Zhao W, Yan J, Xia F, Pereira P. Land degradation neutrality assessment and factors influencing it in China's arid and semiarid regions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 925:171735. [PMID: 38494018 DOI: 10.1016/j.scitotenv.2024.171735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 02/18/2024] [Accepted: 03/13/2024] [Indexed: 03/19/2024]
Abstract
The ecosystems in China's arid and semiarid regions are notably fragile and experiencing dramatic land degradation. At the 12th Conference of the Parties (COP12) to the United Nations Convention to Combat Desertification (UNCCD) in October 2015, a definition for land degradation neutrality (LDN) was proposed and subsequently integrated into the Sustainable Development Goals (SDGs). Research on LDN has developed in terms of conceptual framework constructions, quantitative assessments, and empirical studies. However, LDN and its drivers must be clarified in China's arid and semiarid regions since some representative processes have yet to be fully considered in the assessment. Here, we develop an LDN indicator system specialised for the area, assess their LDN status, and determine the impacts of human activities and climate change on LDN. Our research aims to refine the LDN indicator system tailored for China's arid and semiarid regions by incorporating the trends of wind and water erosion. We also identify the influence of human activity and climate change on LDN, which provides insightful strategies for ecological restoration and sustainable development in drylands with climate-sensitive ecosystems. The results show that: (1) In 2020, more than half of areas of China's arid and semiarid regions achieved LDN, with more pronounced success in the southeastern areas compared to the central regions. (2) For LDN drivers, elevation shows negligible influence on LDN, whereas increased temperature promotes LDN achievement. Conversely, factors like vapour pressure deficit and v-direction wind speed hinder it. In conclusion, China's arid and semiarid regions achieved LDN, and the dominant factor that substantially influences LDN varies across geographical zones, with higher wind speeds and elevated GDP levels generally obstructing LDN in most areas.
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Affiliation(s)
- Siyuan Feng
- School of Public Administration and Policy, Renmin University of China, Beijing 100872, China; State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; Institute of Land Surface System and Sustainable Development, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
| | - Wenwu Zhao
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China; Institute of Land Surface System and Sustainable Development, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
| | - Jinming Yan
- School of Public Administration and Policy, Renmin University of China, Beijing 100872, China.
| | - Fangzhou Xia
- School of Public Administration and Policy, Renmin University of China, Beijing 100872, China.
| | - Paulo Pereira
- Environmental Management Laboratory, Mykolas Romeris University, Vilnius, Lithuania
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Liu Z, Chen Z, Yu G, Yang M, Zhang W, Zhang T, Han L. Ecosystem carbon use efficiency in ecologically vulnerable areas in China: Variation and influencing factors. FRONTIERS IN PLANT SCIENCE 2022; 13:1062055. [PMID: 36578349 PMCID: PMC9791104 DOI: 10.3389/fpls.2022.1062055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
Ecologically vulnerable areas (EVAs) are regions with ecosystems that are fragile and vulnerable to degradation under external disturbances, e.g., environmental changes and human activities. A comprehensive understanding of the climate change characteristics of EVAs in China is of great guiding significance for ecological protection and economic development. The ecosystem carbon use efficiency (CUEe) can be defined as the ratio of the net ecosystem productivity (NEP) to gross primary productivity (GPP), one of the most important ecological indicators of ecosystems, representing the capacity for carbon transfer from the atmosphere to a potential ecosystem carbon sink. Understanding the variation in the CUEe and its controlling factors is paramount for regional carbon budget evaluation. Although many CUEe studies have been performed, the spatial variation characteristics and influencing factors of the CUEe are still unclear, especially in EVAs in China. In this study, we synthesized 55 field measurements (3 forestland sites, 37 grassland sites, 6 cropland sites, 9 wetland sites) of the CUEe to examine its variation and influencing factors in EVAs in China. The results showed that the CUEe in EVAs in China ranged from -0.39 to 0.67 with a mean value of 0.20. There were no significant differences in the CUEe among different vegetation types, but there were significant differences in CUEe among the different EVAs (agro-pastoral ecotones < Tibetan Plateau < arid and semiarid areas < Loess Plateau). The CUEe first decreased and then increased with increasing mean annual temperature (MAT), soil pH and soil organic carbon (SOC) and decreased with increasing mean annual precipitation (MAP). The most important factors affecting the CUEe were biotic factors (NEP, GPP, and leaf area index (LAI)). Biotic factors directly affected the CUEe, while climate (MAT and MAP) and soil factors (soil pH and SOC) exerted indirect effects. The results illustrated the comprehensive effect of environmental factors and ecosystem attributes on CUEe variation, which is of great value for the evaluation of regional ecosystem functions.
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Affiliation(s)
- Zhaogang Liu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Zhi Chen
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Guirui Yu
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Meng Yang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
| | - Weikang Zhang
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Tianyou Zhang
- College of Grassland Agriculture, Northwest A&F University, Yangling, China
| | - Lang Han
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, China
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