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773.
Zhijun Ma Ying Chen David S. Melville Jun Fan Jianguo Liu Jinwei Dong Kun Tan Xuefei Cheng Richard A. Fuller Xiangming Xiao Bo Li 《Conservation biology》2019,33(5):1066-1075
Nature reserves (NR) are the cornerstone of biodiversity conservation. Over the past 60 years, the rapid expansion of NRs in China, one of the world's megadiverse countries, has played a critical role in slowing biodiversity loss. We examined the changes in the number and area of China's NRs from 1956 to 2014 and analyzed the effect of economic development on the expansion of China's NRs from 2005 to 2014 with linear models. Despite a continuing increase in the number of NRs, the total area of China's NRs decreased by 3% from 2007 to 2014. This loss resulted from downsizing and degazettement of existing NRs and a slowdown in the establishment of new ones. Nature reserves in regions with rapid economic development exhibited a greater decrease in area, suggesting that downsizing and degazettement of NRs are closely related to the intensifying competition between economic growth and conservation. For example, boundary adjustments to national NRs, the most strictly protected NRs, along the coast of China's Yellow Sea, a global biodiversity hotspot with a fast-growing economy, resulted in the loss of one-third of the total area. One of the most important ecosystems in these NRs, tidal wetlands, decreased by 27.8% because of boundary adjustments and by 25.2% because of land reclamation. Our results suggest conservation achievement, in terms of both area and quality, are declining at least in some regions in the Chinese NR estate. Although the designation of protected areas that are primarily managed for sustainable use has increased rapidly in recent years in China, we propose that NRs with biodiversity conservation as their main function should not be replaced or weakened. 相似文献
774.
Zhu Shu Zhang Pei Liang Yu Wang Mingxia Xiong Juan Tan Wenfeng 《Environmental science and pollution research international》2020,27(31):38397-38406
Environmental Science and Pollution Research - Proton adsorption behavior on the surface of Al-substituted goethites as a function of pH and ionic strength was investigated and simulated with the... 相似文献
775.
Zhou Xueming Tan Jihua Qin Juanjuan Hu Jingnan Duan Jingchun Chen Rongzhi 《Environmental science and pollution research international》2019,26(12):11875-11887
Environmental Science and Pollution Research - Beijing and its surrounding areas implemented a series of stringent measures to ensure good air quality during the Asia-Pacific Economic Cooperation... 相似文献
776.
国家级公益林生态效益价值核算 总被引:1,自引:0,他引:1
对国家级公益林生态效益的研究是当前制定森林生态补偿政策方面的一个研究热点。构建了国家级公益林生态效益的评估体系,并运用市场价值法、影子价格法等多种方法对国家级公益林的生态效益进行了实物量与价值量评估。结果表明,国家级公益林面积为9.38×1011m2,其生态服务功能的实物量总计为29566.69亿t,提供的生态效益总价值为261179.86亿元,单位面积价值为27.85元/(m2.a)。国家级公益林的生态效益巨大,平衡兼顾其生态效益有助于促进生态保护的协调。 相似文献
777.
Liping Liu Barnabas C. Seyler Hefan Liu Li Zhou Dongyang Chen Song Liu Chang Yan Fumo Yang Danlin Song Qinwen Tan Fengju Ji Cheng Feng Qiuwei Wang Yunchun Li 《环境科学学报(英文版)》2022,34(4):179-193
Integral to the urban ecosystem, greening trees provide many ecological benefits, but the active biogenic volatile organic compounds (BVOCs) they release contribute to the production of ozone and secondary organic aerosols, which harm ambient air quality. It is, therefore, necessary to understand the BVOC emission characteristics of dominant greening tree species and their relative contribution to secondary pollutants in various urban contexts. Consequently, this study utilized a dynamic enclosure system to collect BVOC samples of seven dominant greening tree species in urban Chengdu, Southwest China. Gas chromatography/mass spectrometry was used to analyze the BVOC components and standardized BVOC emission rates of each tree species were then calculated to assess their relative potential to form secondary pollutants. We found obvious differences in the composition of BVOCs emitted by each species. Ficus virens displayed a high isoprene emission rate at 31.472 μgC/(gdw (g dry weight)•hr), while Cinnamomum camphora emitted high volumes of D-Limonene at 93.574 μgC/(gdw•hr). In terms of the BVOC emission rates by leaf area, C. camphora had the highest emission rate of total BVOCs at 13,782.59 μgC/(m2•hr), followed by Cedrus deodara with 5466.86 μgC/(m2•hr). Ginkgo biloba and Osmanthus fragrans mainly emitted oxygenated VOCs with lower overall emission rates. The high BVOC emitters like F. virens, C. camphora, and Magnolia grandiflora have high potential for significantly contributing to environmental secondary pollutants, so should be cautiously considered for future planting. This study provides important implications for improving urban greening efforts for subtropical Chinese urban contexts, like Chengdu. 相似文献
778.
Ying Wang Ailing Zhu Yingying Fang Changjun Fan Yanli Guo Zhiqiang Tan Yongguang Yin Yong Cai Guibin Jiang 《环境科学学报(英文版)》2022,34(5):403-410
A simple and efficient dithizone-functionalized solid-phase extraction (SPE) procedure, online coupled with high-performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry, was developed for the first time for enrichment and determination of ultra-trace mercury (Hg) species (inorganic divalent Hg (Hg(II)), methylmercury (CH3Hg(II)) and ethylmercury (C2H5Hg(II)) in cereals and environmental samples. In the proposed method, functionalization of the commercial C18 column with dithizone, enrichment, and elution of the above Hg species can be completed online with the developed SPE device. A simple solution of 2-mercaptoethanol (1% (V/V)) could be used as an eluent for both the SPE and HPLC separation of Hg species, significantly simplifying the method and instrumentation. The online SPE method was optimized by varying dithizone dose, 2-mercaptoethanol concentration, and sample volume. In addition, the effect of pH, coexisting interfering ions, and salt effect on the enrichment was also discussed. Under the optimized conditions, the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(II), 0.07 ng/L for CH3Hg(II), and 0.04 ng/L for C2H5Hg(II) with recoveries in the range of 85%–100%. The developed dithizone-functionalized C18 SPE column can be reused after a single functionalization, which significantly simplifies the enrichment step. Moreover, the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis. This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples. 相似文献
779.
Wang Haiyan Tan Bo Zhang Xuedong 《Environmental science and pollution research international》2020,27(31):38776-38787
Environmental Science and Pollution Research - Coal gangue hills are prone to spontaneous combustion, thereby polluting the environment of mining areas such as the soil, groundwater, and... 相似文献
780.
Renny K. Hadiaty Heok Hui Tan Lynne R. Parenti Daisy Wowor Sopian Sauri Kwek Yan Chong Darren C. J. Yeo David S. Wilcove 《Conservation biology》2015,29(5):1357-1367
Anthropogenic land‐cover change is driving biodiversity loss worldwide. At the epicenter of this crisis lies Southeast Asia, where biodiversity‐rich forests are being converted to oil‐palm monocultures. As demand for palm oil increases, there is an urgent need to find strategies that maintain biodiversity in plantations. Previous studies found that retaining forest patches within plantations benefited some terrestrial taxa but not others. However, no study has focused on aquatic taxa such as fishes, despite their importance to human well‐being. We assessed the efficacy of forested riparian reserves in conserving freshwater fish biodiversity in oil‐palm monoculture by sampling stream fish communities in an oil‐palm plantation in Central Kalimantan, Indonesia. Forested riparian reserves maintained preconversion local fish species richness and functional diversity. In contrast, local and total species richness, biomass, and functional diversity declined markedly in streams without riparian reserves. Mechanistically, riparian reserves appeared to increase local species richness by increasing leaf litter cover and maintaining coarse substrate. The loss of fishes specializing in leaf litter and coarse substrate decreased functional diversity and altered community composition in oil‐palm plantation streams that lacked riparian reserves. Thus, a land‐sharing strategy that incorporates the retention of forested riparian reserves may maintain the ecological integrity of fish communities in oil‐palm plantations. We urge policy makers and growers to make retention of riparian reserves in oil‐palm plantations standard practice, and we encourage palm‐oil purchasers to source only palm oil from plantations that employ this practice. 相似文献