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Forests are one oi the most important terrestrial ecosystems and play a crucial role in the construction oi ecological civilization. Understanding the changes in gross ecosystem product ( GEP) and its response to land use change in areas with unique advantages in iorest resources is oi great signiiicance for promoting sustainable development. We examined the GEP oi Zixi County oi Jiangxi Province. Based on the theory and method oi ecosystem value accounting, and on the basis oi the general indicator system ior regulating services ( water source conservation, soil conservation, oxygen supply, carbon iixation, climate control, flood regulation, water puriiication, air cleaning, species conservation) and the general indicator system ior cultural services ( landscape recreation, education), we added negative oxygen ions and health care indicators and introduced iorest ecosystem service correction coeiiicients to construct a GEP indicator system and method with unique advantages in forest resources. We evaluated the spatio-temporal variations of GEP in 2010, 2017 and 2020, and quantified the impact of land use/land cover change on GEP by means of elasticity index and value profit and loss analysis. The results showed that the GEP of Zixi County in 2010, 2017 and 2020 was 16.788 billion, 26.817 billion, and 38.407 billion yuan, respectively. Forests contributed the largest amount of GEP, followed by wetland, farmland, grassland, and town. During the study period, the added value of GEP mainly came from forest ecosystems. Land use change had an important impact on GEP. From 2010 to 2020, the total land use change area in the study area was 8501.88 hm2. The amplitude of land use change was grassland (-2811.17 hm2)>town (1428.06 hm2)>forest ( 1357.67 hm2 )> wetland ( 1031.05 hm2) > farmland (-1005.01 hm2). The absolute changes of various land use types were mainly occurred from 2017 to 2020. The elasticity index of each indicator on forest ecosystems was significantly higher than that of other ecosystems, indicating that GEP had the highest sensitivity to changes in forest area. The results of value profit and loss analysis showed that urban development had reduced GEP to some extent, while the protection of forest and wetland had increased GEP. From 2010 to 2020, the conversion of land use types in Zixi County led to an increase of 1.865 billion yuan in GEP, indicating that land use change in Zixi County had a positive ecological impact on the whole. Our results reflect the green development effect of Zixi County after becoming a national ecological civilization construction demonstration county, which could provide decision-making support for high-quality development, high-level protection and sustainable development and utilization of land resources in the future, and provide reference for other similar areas of GEP accounting. [ABSTRACT FROM AUTHOR]

Compound climate events often pose greater harm to humans and society than single-variable climate issues. This study projects the temporal changes and spatial pattern evolution of four compound climate events (including warm–wet, warm–dry, cold–wet, and cold–dry) and the corresponding population exposure in global land under the shared socioeconomic pathway (SSP) 2–4.5 based on the Coupled Model Intercomparison Project phase 6 simulations. Results show the following: (1) The warm–wet event is significantly decreasing at a rate of 0.06 days per decade, while the cold–wet event is significantly increasing at a rate of 0.06 days per decade. The warm–dry event and cold–dry event show an upward trend but are not significant. (2) All four types of compound events will undergo mutations in the next 80 years, with the warm–dry event having the highest frequency of mutations. (3) West Asia is a high-risk area for warm–dry and cold–wet events. Northern Africa is a hot spot area for the warm–wet event, while Brazil is a hot spot area for the cold–dry event. (4) Areas with exposure levels (population under four compound climate events) of medium or higher are mainly distributed in East Asia, South Asia, and central Africa. When the population exposure exceeds 105 person · day, the area of population exposure to compound events related to dry conditions is greater than that of compound events related to wet conditions. This study has guiding significance for understanding, identifying, analyzing, and preventing compound extreme climate events in the context of global warming. [ABSTRACT FROM AUTHOR]