Exploring long‐term datasets of land use, economy, and demography variations in karst wetland areas to detect possible microclimate changes

Abstract

This study explores the possibility of deciphering changes in the total area of a karst wetland due to shifts inland use, economy and population over a long-term period (35 years) and microclimate changes . To achieve this goal, we focused on Huangcaozhou Karst Wetland, a national karst wetland park located in China. Based on remote sensing interpretation, long-term climate data, and statistical yearbook datasets, our results showed that from 1984 to 2019, owing to the rapid rates of urbanization and economic development, swamplands in our study area decreased by 16.4%, while urban lands increased up to 16.7%. The inflection point on the land use and land cover (LUCC) curve we constructed appeared in 2006, after which the areas of swampland, rocky desertification land, and wasteland sharply decreased and those of urban land and farmland increased. This is consistent with the increase in gross domestic production (GDP) and the totalnumber of inhabitants. From 1958, when Luxi registered an annual average temperature of 14.8 C, to 2019, the air temperature increased with a gradient of 0.157 C per decade, until it reached an average of 15.3 C. We did not find a clear trend for the number of annual rainy days (average of 140.6 rainy days per year) but the mean torrentiality (average annual volume divided by the annual number of rainy days) shows a slight trend of increase (0.72 mm per day per decade). Precipitation we found has gradually declined. We concluded that economic and demographic changes are interacting with microclimate changes, which are affected by the regional eco-environment over a long-time scale in the Huangcaozhou Karst Wetland, causing the wetland quality significantly varied in recent decades. This would help to develop more efficient land management plans to better correctly handle new human activities allowing policymakers to regulate the wetland ecosystem in Southwestern China.

Health risk assessment of heavy metal pollution in groundwater of a karst basin, SW China

“…Comparing these concentrations with the limit values specified for Grade Ⅲ water in the Standard for Surface Water Environmental Quality (GB 3838−2002), Standard Groundwater Quality (GB/T 148−2017), the Standard for Drinking Water Quality (GB 5749−2006), as well as the US EPA drinking water quality standard (Lan et al 2022;EPA, 2006), revealed that concentrations of Al, Pb, Zn, Fe, Cd, Mn, As and Hg in our water samples exceeded all three standard limitations mentioned above. The maximum concentrations of these elements exceeding the standard limitations reached 26.37, 12.40, 1.31, 25.97, 12.20, 20.34, 5.47 and 9.40 times of the standards, respectively.…”

“…In our integrated health risk study of adults and children exposed to metal elements in water across China, it was observed that health risks in most regions primarily stem from carcinogenic metal elements, particularly Cr in the water (USEPA, 1992;Li, 2020;Lan et al 2022). In our investigation within the Nandong Underground River Basin (NURB), we identified that the main source of health risk for local residents exposed to metal elements in the water is also Cr, followed by Cd and As.…”

“…Moreover, the universal nature of exposure parameters in health risk assessment models might overlook individual differences. Additionally, the heterogeneity of the metal concentrations in the water can result in spatial and temporal variations, introducing uncertainty into the evaluation results (Lan et al 2022).…”

Concentration Characteristics and Health Risk Assessment of Heavy Metals in the Water of Nandong Underground River Watershed, China

“…Among these elements, Fe, Al and Mn show the higher concentrations than the other 8 elements, and reach 10 -2 μg•L -1 range. According to the limit values of Grade Ⅲ water specifies in Standard for Surface Water Environmental Quality (GB 3838-2002), Standard for Groundwater Quality (GB/T 148-2017), the Standard for Drinking Water Quality (GB 5749-2006) and the US EPA drinking water quality standard [29,30,31,32,33], the concentrations of Al, Pb, Zn, Fe, Cd, Mn, As and Hg from our water samples exceeded all the three standard limitations mentioned above. Maximum concentrations of all the exceeded standard limitations elements reached 26.37, 12.40, 1.31, 25.97, 12.20, 20.34, 5.47 and 9.40 multiple of standards respectively.…”

pH-Related Changes in Soil Bacterial Communities in the Sanjiang Plain, Northeast China

“…Wetlands have the unique characteristics of land and water systems, with distinct ecosystem structures, processes, and functions, e.g., water purification, water conservation, flood storage and regulation, pollution degradation, climate regulation, and regional water cycles [1,2]. Therefore, wetland ecosystems provide important contributions to ecotourism and biodiversity conservation [3][4][5]. Soils are the dominant component of wetlands and play important ecological functions in the wetland biogeochemical cycle and vegetation composition [6].…”