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Pb(II) contamination in aquatic environments has adverse effects on humans even at a low concentration, so the efficient removal of Pb at a low cost is vital for achieving an environmentally friendly, sustainable, and healthy society. A variety of CaCO3-based functional adsorbents have been synthesized to remove Pb, but the adsorption capacity is still unsatisfactory. Herein, calcite CaCO3 microcubes/parallelepipeds are synthesized via simple precipitation and a hydrothermal approach and found to outperform previously reported nano-adsorbents considerably. The CaCO3 achieves a high removal efficiency for Pb(II) (>99%) at a very low dosage (0.04–0.1 g/L) and an initial Pb(II) concentration of 100 mg/L. The CaCO3 presents an excellent adsorption capacity of 4018 mg/g for Pb(II) removal and depicts good stability over a wide range of pH 6–11. The maximum adsorption kinetics are fitted well by the pseudo-second-order kinetic model, whereas the Freundlich isotherm delineates the adsorption data at equilibrium well, indicating a multilayer adsorption process. The ex situ study confirms that the Pb(II) adsorption mechanism by CaCO3 can be attributed to the rapid metal-ion-exchange reaction between Pb(II) and Ca2+. Furthermore, a red shift in the Fourier Transform Infrared (FTIR) spectroscopy peak from 1386 cm−1 to 1374 cm−1 of CaCO3 after Pb removal indicates the adsorption of Pb onto the surface. This adsorbent provides an opportunity to treat wastewater and can be extended to remove other toxic heavy metals. [ABSTRACT FROM AUTHOR]

In the context of achieving global carbon neutrality, forests play a pivotal role in sequestering atmospheric CO2, particularly in China, where forest management is central to national climate strategies. This study evaluates the forest carbon sink capacity in Zixi County, a subtropical region, under varying climate scenarios (SSP2-4.5 and SSP5-8.5). Using the Forest-DNDC (Denitrification–Decomposition) model, combined with high-precision climate data and a random forest model, we simulate forest carbon density and forest carbon sink under different management strategies. The results indicate that under the baseline scenario, forest carbon density in Zixi County increases by 31% over 42 years under the SSP2-4.5 climate scenario and by 28.6% under SSP5-8.5. In the enhancing economic scenario, carbon density increases by 8.5% under SSP2-4.5 and by 7.2% under SSP5-8.5. For the natural development scenario, a significant increase of 130% is observed under SSP2-4.5, while SSP5-8.5 shows an increase of 120%. Spatially, forest carbon sinks in Zixi County total 843,152 T C in 2020, 542,852 T C in 2030, and 877,802 T C in 2060 under the baseline SSP2-4.5 scenario; under SSP5-8.5, these values are 841,321 T C in 2020, 531,301 T C in 2030, and 1,016,402 T C in 2060. In the enhancing economic scenario, the total carbon sink is 34,650 T C in both 2020 and 2030, increasing to 427,351 T C in 2060 under SSP2-4.5, while under SSP5-8.5, it is 46,200 T C in 2020, 34,650 T C in 2030, and 415,801 T C in 2060. The natural development scenario shows the total carbon sink under SSP2-4.5 as 11,157,332 T C in 2020, 3,441,910 T C in 2030, and 1,409,104 T C in 2060, and under SSP5-8.5, it is 10,903,231 T C in 2020, 3,337,960 T C in 2030, and 1,131,903 T C in 2060. Spatial analysis reveals that elevation and forest type significantly affect carbon density, with high-altitude areas and forests dominated by Chinese fir and broadleaf species showing higher carbon accumulation. The findings highlight the importance of targeted forest management, prioritizing species with higher carbon sequestration potential and considering spatial heterogeneity. These strategies, applied locally, can contribute to broader national and global carbon neutrality efforts. [ABSTRACT FROM AUTHOR]

Climate change exerts substantial impacts on human society and the carbon cycle of terrestrial ecosystems. Studying the spatiotemporal characteristics of regional climate change and its impact on carbon sequestration is an important topic in ecology and environmental science. This study utilized meteorological and land use/cover data to explore these dynamics. Statistical methods such as the Mann–Kendall (M-K) test and wavelet analysis were used to simulate the changes in annual average temperature and precipitation in the Poyang Lake Basin from 1980 to 2020. The Carnegie–Ames–Stanford Approach (CASA) model was used to estimate the interannual variation in net primary productivity (NPP) in the region over the past 40 years. Additionally, the present study examined the influence of various factors on NPP changes. The main results are as follows: (1) Over the past four decades, the average temperature in the Poyang Lake Basin was 17.85 °C, while the average precipitation was 1621.35 mm. The average annual temperature rises at a rate of 0.27 °C per decade. (2) A significant shift in the average annual temperature occurred in the early 21st century, and annual precipitation exhibited multiple abrupt changes during the mid-to-late 1990s. Both temperature and precipitation changes follow a 25-year cycle, with temperature hotspots located in the south and precipitation hotspots in the northeast. (3) The impact of climate change on the change in NPP in the Poyang Lake Basin is about 70%, with the annual average temperature having a significant effect on the increase in NPP. This study can provide a scientific foundation for formulating policies aimed at mitigating climate-related disasters and enhancing carbon cycling in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Forests are one of the largest terrestrial ecosystems on Earth, absorbing carbon dioxide from the atmosphere through photosynthesis and storing it as organic carbon, thereby mitigating global warming. Conducting bibliometric analysis of forest carbon storage can identify current research trends and hot issues in this field, providing data support for researchers and policy makers. This review article provides a comprehensive bibliometric analysis of global forest carbon storage research, using databases from the Web of Science Core Collection. CiteSpace software (6.2.6 version) was employed to visualize and analyze the data, focusing on key researchers, institutions, and countries, as well as major research themes and emerging trends. The main findings are as follows: (1) Since the 21st century, the publication volume in this field has been increasing, with the United States and China being the top contributors. (2) There is active collaboration among key authors, institutions, and countries, with a notable close-knit network centered around French author Philippe Ciais. This group includes nearly half of the field's authors and many of them are crucial for advancing research in this field. (3) Cluster and citation burst analyses suggest that future research will focus more on the impact of forest management policies on carbon stocks, with particular attention to the roles of northern temperate forests and mangroves in global carbon storage. These findings provide valuable insights into the current state and future directions of forest carbon storage research. This article is instrumental in elucidating the role of forest ecosystems within the global carbon cycle, evaluating the impacts of anthropogenic activities on forest carbon stocks, and informing the development of effective climate change mitigation strategies. [ABSTRACT FROM AUTHOR]

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]