Abstract
Understanding the changing relationships between vegetation coverage and precipitation/temperature (P/T) and then exploring their potential drivers are highly necessary for ecosystem management under the backdrop of a changing environment. The Jing River Basin (JRB), a typical eco-environmentally vulnerable region of the Loess Plateau, was chosen to identify abrupt variations of the relationships between seasonal Normalized Difference Vegetation Index (NDVI) and P/T through a copula-based method. By considering the climatic/large-scale atmospheric circulation patterns and human activities, the potential causes of the non-stationarity of the relationship between NDVI and P/T were revealed. Results indicated that (1) the copula-based framework introduced in this study is more reasonable and reliable than the traditional double-mass curves method in detecting change points of vegetation and climate relationships;(2) generally, no significant change points were identified during 1982-2010 at the 95% confidence level, implying the overall stationary relationship still exists, while the relationships between spring NDVI and P/T, autumn NDVI and P have slightly changed;(3) teleconnection factors (including Arctic Oscillation (AO), Pacific Decadal Oscillation (PDO), Nino 3.4, and sunspots) have a more significant influence on the relationship between seasonal NDVI and P/T than local climatic factors (including potential evapotranspiration and soil moisture);(4) negative human activities (expansion of farmland and urban areas) and positive human activities (Grain For Green program) were also potential factors affecting the relationship between NDVI and P/T. This study provides a new and reliable insight into detecting the non-stationarity of the relationship between NDVI and P/T, which will be beneficial for further revealing the connection between the atmosphere and ecosystems.
Dokumententyp: | Zeitschriftenartikel |
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Fakultät: | Geowissenschaften > Department für Geographie |
Themengebiete: | 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie |
Sprache: | Englisch |
Dokumenten ID: | 84176 |
Datum der Veröffentlichung auf Open Access LMU: | 15. Dez. 2021, 15:10 |
Letzte Änderungen: | 15. Dez. 2021, 15:10 |