Vegetation in Arid Areas of the Loess Plateau Showed More Sensitivity of Water-Use Efficiency to Seasonal Drought

Abstract

Studying the impact of regional or seasonal drought on vegetation water-use efficiency (WUE) can identify an effective theoretical basis by which vegetation can cope with future climate change. Based on remote sensing data and climate grid data, in this study, we calculated the ecosystem WUE and standardized precipitation evapotranspiration index (SPEI), analyzed the temporal and spatial divergence of seasonal drought and WUE, and explored the relationship between WUE and seasonal drought in the Loess Plateau. The results indicate that from 2001 to 2019, the humidity in spring and summer on the Loess Plateau shows an increasing trend, and the aridity in fall also shows an increasing trend. Averaged over four seasons, WUE presents distribution characteristics of “high in the southeast and low in the northwest”, with the highest WUE in summer. However, the geological distribution of the sensitivity of WUE to seasonal drought was significantly different. Spring drought increased WUE, whereas summer drought led to a decrease in WUE. When fall drought was less severe, the WUE increased; WUE response to winter SPEI was negative, but the sensitivity did not change with variation of drought degree. The sensitivity of WUE to the magnitude of seasonal drought was affected by regional dry and wet conditions. A clear seasonal divergence was found in four climate regions, along with increased drought intensity, and the sensitivity of WUE to drought magnitude in arid areas was generally higher than that in semi-arid, semi-humid areas, or humid areas. With this study, we deeply explored how ecosystems deal with the water supply strategy of seasonal drought, which is of great significance in the understanding of the coupling relationship between the carbon–water cycle and climate change.

Land Use Change Analysis to Springs Conditions in Gunungpati Sub-District, Semarang City

“…Residents have mostly used Spring water with clear water to meet household needs and drinking water sources, such as Gede spring in Kandri Village and Bahurekso spring in Pakintelan village. The clarity of the spring is affected by the condition of the surrounding vegetation (Ansari et al, 2021;Pei et al, 2022;Krogh & Pomeroy, 2019). The Table 3 presents the results of measurements of pH, temperature and turbidity of the springs.…”

Stronger Cumulative than Lagged Effects of Drought on Vegetation in Central Asia

“…It can also provide a record of hydrological climate change [2]. Drought is one of the major limiting factors for terrestrial ecosystems, with significant ecological and human amenity impacts [3]. An important feature of drought is low soil water use efficiency, which is usually caused by reduced rainfall and increased evapotranspiration [4].…”