Evaluating the impact of karst rocky desertification on regional climate in Southwest China with WRF

Abstract

It has been confirmed that the karst rocky desertification (KRD) has severely changed the interactions between atmosphere and terrestrial ecosystem which would cause a significant effect on regional climate system. In this study, the Weather and Research Forecasting model was applied to investigate the biogeophysical impact on temperature and precipitation change by land use/land cover change data with different KRD conditions in 1993KRD conditions in , 2003KRD conditions in , and 2013 in Southwest China. The results showed that an improving trend of KRD has been found in Southwest China, especially in east Sichuan, Chungking, southwest Yunnan, and south Guangxi. The 2-m air temperature decreased by 0~− 1°C in general with this improving trend. The possible reason was the decreasing KRD accompanied by the decreasing albedo, causing the increasing net shortwave radiation and the increasing net radiation. Meanwhile, the increasing evaporation strengthened the latent heat flux and weakened the sensible heat flux so that decreased temperature was addressed in forest areas. The effect of KRD change transferred to the upper troposphere through atmosphere vertical convection, which made the subtropical high to be strengthened and westerly extended. Therefore, the upward moisture flux at the surface (QFX) was weakened in the central part of Guangxi, southern Guizhou, which led to the decrease of the precipitation. Moreover, the southwest monsoon was strengthened, which caused the increasing water vapor flux and led to the heavy rainfall in the west of Yunnan.

Human–desertification coupling relationship in a karst region of China

“…Conversely, a decrease in KRD can improve the regional environment and benefit production and living conditions. For example, increasing the vegetation cover and thus lowering bedrock exposure decreases the local temperature, favoring crop growth and yield (Yang et al, 2019). In the environment restoration process, combating KRD and alleviating poverty are closely linked with the increase of ecological and economic benefits (Li & Xiong, 2021;Zhang et al, 2016).…”

A stratified environmental reference system for better understanding of the relationship between remote sensing observations and ground monitoring of karst rocky desertification

“…Our present findings clarify that the use of an invariant reference state across the whole study area is questionable, particularly for studies conducted over a large geographic area (Liu et al, 2015; Zhang et al, 2017). Low NDVI values are easily identified as high KRD classes in several case studies (Yang et al, 2019; Zhang et al, 2017), however, not KRD but low temperatures in high elevations may limit the vegetation growth and result in the low NDVI. We suspect that this is why incidences of KRD mapping biases were found in previous studies in south‐western China when using a uniform reference.…”

Research on the Resilience Assessment of Rural Landscapes in the Context of Karst Rocky Desertification Control: A Case Study of Fanhua Village in Guizhou Province

“…The degree of influence (D i ) and the degree of influence (C i ) of an element i were added to obtain the centrality of the element, denoted as M i . Centrality indicates the position of the factor in the evaluation index system and the size of its role, as shown in Equation (11).…”

“…Under the background of the Chinese government's implementation of KRDC and ecological civilization construction, China's ecological environment and landscape pattern have undergone significant changes [8][9][10]. The serious KRD problem in karst areas of Southwest China has been gradually addressed, the degree of KRD has been reduced, and the impact of ecological damage has diminished [11][12][13]. The results of China KRD monitoring showed that the area of KRD in Guizhou Province decreased by 8457 km 2 in 2016 compared with 2005 [14].…”