替代稳态下阜康北部荒漠生态弹性的时空格局

Abstract: The ecological resilience of desert ecosystems under alternative stable states reflects the ecosystem’s ability to recover from environmental disturbances, which has important theoretical implications for understanding the desert ecosystem processes. Recent research has focused on some intensively studied ecosystems such as lakes and forests, whereas studies related to the ecological resilience of desert ecosystems have hardly considered alternative stable states as well as the temporal changes in resilience. In this study, based on the MODIS global vegetation index from January 2001 to December 2020, we used Breaks for Additive Season and Trend and state- space modeling to determine the temporal- spatial pattern of ecological resilience under alternative stable states quantified by the exit times for a transect extending from the southern edge to the hinterland of Gurbantunggut Desert in north Fukang. Moreover, mechanisms underlying the temporal- spatial pattern of ecological resilience were explored. The results of this study indicated the following: (1) Resilience+ and Resilience− showed a decreasing trend within the study period but with significant differences between the southern edge and the hinterland of the desert. (2) Ecological resilience also showed a lagged response to precipitation changes. (3) Differences in the seasonal patterns of precipitation could weaken the correlation between precipitation and ecological resilience. In summary, the spatial distribution of ecological resilience is generally controlled by the precipitation patterns, but the spatial heterogeneity of vegetation due to site conditions increases the complexity of the spatial distribution of ecological resilience, with the relationship between ecological resilience and precipitation resulting from the combined effects of the composition of vegetation, adaptation of plants to changes in precipitation, and the seasonal pattern of precipitation. Our study is important for understanding the mechanisms that desert ecosystems utilize to maintain functional stability as well as in desert conservation and ecological restoration.