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1.
Glob Chang Biol ; 30(4): e17280, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613249

RESUMO

Coastal wetlands play an important role in regulating atmospheric carbon dioxide (CO2) concentrations and contribute significantly to climate change mitigation. However, climate change, reclamation, and restoration have been causing substantial changes in coastal wetland areas and carbon exchange in China during recent decades. Here we compiled a carbon flux database consisting of 15 coastal wetland sites to assess the magnitude, patterns, and drivers of carbon fluxes and to compare fluxes among contrasting natural, disturbed, and restored wetlands. The natural coastal wetlands have the average net ecosystem exchange of CO2 (NEE) of -577 g C m-2 year-1, with -821 g C m-2 year-1 for mangrove forests and -430 g C m-2 year-1 for salt marshes. There are pronounced latitudinal patterns for carbon dioxide exchange of natural coastal wetlands: NEE increased whereas gross primary production (GPP) and respiration of ecosystem decreased with increasing latitude. Distinct environmental factors drive annual variations of GPP between mangroves and salt marshes; temperature was the dominant controlling factor in salt marshes, while temperature, precipitation, and solar radiation were co-dominant in mangroves. Meanwhile, both anthropogenic reclamation and restoration had substantial effects on coastal wetland carbon fluxes, and the effect of the anthropogenic perturbation in mangroves was more extensive than that in salt marshes. Furthermore, from 1980 to 2020, anthropogenic reclamation of China's coastal wetlands caused a carbon loss of ~3720 Gg C, while the mangrove restoration project during the period of 2021-2025 may switch restored coastal wetlands from a carbon source to carbon sink with a net carbon gain of 73 Gg C. The comparison of carbon fluxes among these coastal wetlands can improve our understanding of how anthropogenic perturbation can affect the potentials of coastal blue carbon in China, which has implications for informing conservation and restoration strategies and efforts of coastal wetlands.


Assuntos
Ecossistema , Áreas Alagadas , Dióxido de Carbono , Ciclo do Carbono , China
2.
J Environ Manage ; 358: 120921, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38652992

RESUMO

Ecological vulnerability and poverty are interrelated and must be addressed together. The resolution of this issue will help us to meet the challenges during the process of implementing concrete actions for realizing the 2030 UN sustainable development goals (SDGs). Ecological restoration projects (ERPs) can enhance ecosystem services (ESs) while providing policy support for improving people's livelihoods. However, processes and mechanisms of ERPs on the ecological environment and socioeconomic development in poverty-stricken and ecologically fragile areas have rarely been studied. To address these issues, we conducted a comparative analysis on the changes of land use and land cover (LULC), ecosystem services (ESs), and socioeconomic development in Bijie City, a karst rocky desertification area in southwest China, before and after the implementation of ERPs in 2000, as well as the complex relationship between these factors. ERPs have affected LULCs, ESs, socioeconomics, and poverty reduction significantly since 2000. Specifically, the total ecosystem service value (ESV) in the study area has increased by more than 3 times in the past 30 years, with the ESV of tourism services and carbon storage increasing the most, from CNY 0.001 and 337.07 billion in 1990 to CNY 11.07 and 108.97 billion in 2019, respectively. The correlation between ESs is mainly synergistic, while the tradeoff between carbon storage and water yield is in a fluctuating upward trend. LULC conversion of cropland to green, and cropland to water, wetland and shrubs has positive effects on carbon storage and water yield, respectively. During study period, GDP, urbanization increased by over 70 times, 5 times, respectively, whereas poverty population, poverty incidence, and employment rate of various sectors (i.e., agriculture, forest, animal, and fishery, or AFAF) decreased by 96.4%, 97.7%, and 18.24%, respectively. Our findings emphasized that ERPs can effectively help poor and ecologically fragile areas to get out of the poverty trap and achieve the "win-win" goals of ecological and socio-economic sustainable development. These results have profound environmental management references to China and other developing countries around the world in realizing ecological restoration, poverty reduction, and the SDGs.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Pobreza , China , Desenvolvimento Sustentável , Ecologia , Humanos
3.
Int J Biol Macromol ; 279(Pt 2): 135262, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39241993

RESUMO

Reducing pesticide residues while extending their efficacy period is a critical challenge in the development of controlled-release pesticides. This study focuses on loading avermectin onto lignin-modified epoxy resin nanocarriers via the creation of photostable nanocapsules (NCs) for evaluating their efficacy against Plutella xylostella. This study also assesses the NCs' resistance to water scour on plant leaves by comparing them with traditional preparations. These NCs feature a stable core-shell structure, an encapsulation efficiency of 92.90 % and slow-release properties. Compared to emulsifiable concentrate (EC) and microemulsion (ME) under UV irradiation, the loading of nanocarriers significantly prolonged the degradation time of avermectin by fivefold. The Nano-formula demonstrated enhanced insecticidal activity in comparison to traditional preparations. Field tests revealed that the efficacy of the NCs on Day 7 (92.55 %) and Day 14 (78.54 %) significantly surpassed that of traditional preparations. Additionally, NCs are more readily washed off cabbage leaves by water than EC and ME, aiding in the reduction of pesticide residues. This technology is particularly suitable for leafy vegetable crops in arid regions or greenhouses, enhancing effectiveness period while minimizing pesticide residues. This research offers novel insights and directions for the development of controlled-release pesticides.


Assuntos
Portadores de Fármacos , Inocuidade dos Alimentos , Inseticidas , Ivermectina , Nanocápsulas , Portadores de Fármacos/química , Portadores de Fármacos/efeitos da radiação , Portadores de Fármacos/normas , Lignina/química , Resinas Epóxi/química , Inseticidas/química , Inseticidas/efeitos da radiação , Inseticidas/normas , Resíduos de Praguicidas/análise , Nanocápsulas/química , Nanocápsulas/efeitos da radiação , Nanocápsulas/normas , Raios Ultravioleta , Ivermectina/análogos & derivados , Brassica/química , Folhas de Planta/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/efeitos da radiação , Preparações de Ação Retardada/normas
4.
Sci Total Environ ; 926: 172093, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38556019

RESUMO

Monitoring ecological resource change in mountainous and hilly areas (MHAs) is vital for theoretical and practical advancements of ecological resource utilization and management in complex ecosystems. The factors driving structural and functional changes in green eco-spaces (GES) in these areas are complex and uncertain, with notable spatial scale effects. However, analyzing the multi-scale driving mechanisms of ecological and socioeconomic factors at a fine spatiotemporal scale presents significant challenges. To address these challenges, we analyzed dynamic changes in GES and eco-socio-economic development in Shanghang County, a typical mountainous region in southern China. We used multiple linear regression and multi-scale geographically weighted regression model to identify key factors driving GES changes and their multi-scale effects at both global and local levels. Over the past two decades, the GES area in the study area has exhibited a consistent pattern of decline, characterized by phases of gradual decline (2000-2005), sharp decline (2005-2009), slow decline (2009-2019). Key global factors driving GES changes included elevation (ELE), slope (SLOPE), population density (PD), distance to settlements (SETTLE), and distance to administrative centers (ADMIN). These factors exhibited significant spatial heterogeneity and multi-scale effects on GES changes. Specifically, SETTLE, PD, SLOPE, and ELE consistently drove GES changes at the local level, while ADMIN only showed significant localized effects during 2005-2009. The synergy between SETTLE and SLOPE had a considerable impact on GES changes, increasing over time, whereas ELE and PD demonstrated a consistent trade-off effect. These findings provide detailed spatiotemporal insights into the driving mechanisms of natural ecological resources, offering crucial guidance for environmental management, land source management, regional economic development, and biodiversity conservation in Shanghang and analogous subtropical hilly regions worldwide.

5.
Mol Biomed ; 4(1): 38, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37922035

RESUMO

Recent studies challenge the dogma that a 21-mer phosphopeptide P140 protects against direct cell damage in the phase-III clinical trial (NCT02504645) for lupus, involving reactive oxygen species (ROS)-dependent release of citrullinated histone H3 (H3cit)-linked neutrophil extracellular traps. An open question is the cellular location of ROS production and H3cit formation in lupus. In this study, we examined the effects of P140 peptides on ROS production and H3cit location in lupus with in vivo and situ fluorescence imaging with subcellular resolution. We developed a mouse model of the B6 strain harbouring a bioluminescent reporter under the control of the Lysozyme M promoter. Based on the imiquimod-induced disease model of B6 mice, we used bioluminescent imaging, flow cytometry analysis, and immunohistology staining to study the effects of P140 peptides in lupus. We found a profound accumulation of CX3CR1-positive macrophages in the lungs of lupus mice after the application of P140, accompanied by lung fibrosis formation. The defined P140-mediated macrophage responses were associated with an increase of H3cit in the cytosol, interleukin-1 receptor type 1 on the extracellular membrane, and intracellular production of ROS. Of interest, the disease of imiquimod-induced lupus was prevented with an antioxidant drug apocynin. This study shows that P140 peptides play a role in aggravated murine lupus in a manner dependent on ROS production and H3cit upregulation through pulmonary macrophages.

6.
Sci Total Environ ; 898: 165515, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37451465

RESUMO

Urbanization shows continuous expansion and development, ushering in the co-evolution of urban environments and vegetation over time. Recent remote sensing-based studies have discovered prevalent vegetation growth enhancement in urban environments. However, whether there is a temporal evolution of the growth enhancement remains unknown and unexplored. Here we expanded the existing framework for assessing the long-term impact of urbanization on vegetation greenness (enhanced vegetation index, EVI) using long time series of remote sensing images and applied it in Changsha, the capital city of Hunan province in China. Results showed that vegetation growth experienced widespread enhancement from 2000 to 2017, and increased 1.8 times from 2000 to 2017, suggesting strong continuous adaptive capability of vegetation to urban conditions. Although the overall impact of urbanization was negative due to the replacement of vegetated surfaces, the growth enhancement nevertheless offset or compensated the direct loss of vegetated cover during urbanization in the magnitude of 28 % in 2000 to 44 % in 2017. Our study also revealed large spatial heterogeneity in vegetation growth response among various districts at different urbanization levels and found an emergent trend under the observed spatial heterogeneity toward an asymptotic maximum with urbanization, showing EVI converges to 0.22 in highly urbanized areas. We further found that the positive effect of urbanization on vegetation growth is a function of urbanization intensity and time, which implies that the effect of the urban environment on vegetation can be simulated and predicted, and can be verified in more cities in the future. Our study is the first to successfully quantify long-term spatial patterns on the co-evolution of urbanization and vegetation, providing a new understanding of the continuous adaptive responses of vegetation growth to urbanization and shedding light on predicting biological responses to future environmental change.


Assuntos
Monitoramento Ambiental , Urbanização , Monitoramento Ambiental/métodos , Cidades , China , Telemetria
7.
Sci Total Environ ; 863: 160705, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36496025

RESUMO

Understanding the co-evolution and organizational dynamics of urban properties (i.e., urban scaling) is the science base for pursuing synergies toward sustainable cities and society. The generalization of urban scaling theory yet requires more studies from various developmental regimes and across time. Here, we extend the universality proposition by exploring the evolution of longitudinal and transversal scaling of Chinese urban attributes between 1987 and 2018 using a global artificial impervious area (GAIA) remotely sensed dataset, harmonized night light data (NTL), and socioeconomic data, and revealed agreements and disagreements with theories. The superlinear relationship of urban area and population often considered as an indicator of wasting land resources (challenging the universality theory ßc = 2/3), is in fact the powerful impetus (capital raising) behind the concurrent superlinear expansion of socio-economic metabolisms (e.g., GDP, total wage) in a rapidly urbanizing country that has not yet reached equilibrium. Similarly, infrastructural variables associated with public services, such as hospitals and educational institutions, exhibited some deviations as well and were scaled linearly. However, the temporal narrowing of spatial deviations, such as the decline in urban land diseconomies of scale and the stabilization of economic output, clearly indicates the Chinese government's effort in charting urban systems toward balanced and sustainable development across the country. More importantly, the transversal sublinear scaling of areal-based socio-economic variables was inconsistent with the theoretical concept of increasing returns to scale, thus validating the view that a single measurement cannot unravel the intricate web of diverse urban attributes and urbanization. Our dynamic urban scaling analysis across space and through time in China provides new insights into the evolving nexus of urbanization, socioeconomic development, and national policies.

8.
Heliyon ; 8(8): e10043, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35991979

RESUMO

It is challenging to visualize noninvasively the formation of neutrophil extracellular traps, known as NETosis, and therefore difficult to monitor disease progression. A desirable molecular imaging probe is the iron oxide nanoparticle (NP) that could induce reactive oxygen species. Here, we used C57BL/6 mice with pristane-induced lupus, which mimics systemic lupus erythematosus. Administration of anti-Ly6G antibody-conjugated NP allowed detection of NETosis with fluorescent molecular imaging, as evidenced by flow cytometric analysis of citrullinated histone H3 expression in lung neutrophils. This finding was consistent with NP-induced blood NETosis in a spontaneous lupus model of B6.MRL-lpr mice. A chronic assessment was performed in which the lupus mice were protected from enhanced oxidative burst by anti-Ly6G NP. This NP can migrate from the peritoneal cavity to the lungs, as visualized by magnetic particle imaging. Overall, our study provides evidence for a highly sensitive assessment of NETosis in lupus through magnetic particle imaging.

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