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Environmental and Human Impacts of Lancang-Mekong Mainstem and Tributary Dams on China, Laos, Thailand, Myanmar, Cambodia, and Vietnam
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作者 Kenneth Ray Olson Wadslin Frenelus 《Open Journal of Soil Science》 2024年第10期555-605,共51页
The Lancang-Mekong River in China, Laos, Thailand, Myanmar, Cambodia, and Vietnam is the soul and heart of mainland Southeast Asia. Over 60 million people depend on the river and its tributaries for food, transportati... The Lancang-Mekong River in China, Laos, Thailand, Myanmar, Cambodia, and Vietnam is the soul and heart of mainland Southeast Asia. Over 60 million people depend on the river and its tributaries for food, transportation, water, and other necessities of life. The river supports one of the world’s most diverse fisheries, second only to Brazil’s Amazon River. Lancang-Mekong and tributaries are already heavily dammed primarily in China, Laos, Thailand, and Cambodia, with many more dams planned or under construction. Dams can worsen the impact of periodic droughts in the Lancang-Mekong basin and block the river’s “pulse effect” that spreads water and nutrients needed for fishing and farming onto the floodplains and delta. The headwaters of the Lancang are in China and its waters are considered a national resource. China regards the Lancang, Yangtze and Yellow rivers as a free resource rather than a shared resource. The primary difference between these rivers is the Lancang flows from China into and through other countries and not directly into a sea or ocean. China and Myanmar have not joined the Mekong River Commission (MRC) as full members but have been Dialogue Partners since 1996. Over the past thirty years, China’s Lancang policies and actions have reflected its national resource interests. China has actively engaged with individual transboundary countries at various levels including environmental, conservation, and economic agreements. The primary objective of this study is to assess the environmental and human impacts of all Lancang-Mekong mainstem and tributary dams and the plans by many countries for more hydropower utilizing the potential of the river as the continent’s energy lifeline. Future dams need to include fish ladders and navigation locks to reduce the environmental impacts on fish populations, natural resources, navigation, and livelihoods. Strengthening of international collaboration via the MRC or by individual or multiple country agreements to address Lancang-Mekong’s sustainable transboundary development goals is recommended. When new Lancang-Mekong and tributary dams are built within any of the transboundary watershed countries, additional communities will need to be resettled. Significant environmental and human impacts are observed. Steps will have to be taken by all the concerned countries to prevent these problems and to ensure that people’s livelihoods are restored after resettlement. 展开更多
关键词 Lancang-Mekong River DAMS human Activities Environmental impacts
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Human impact recorded in the sediment of Honghu Lake, Hubei, China 被引量:6
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作者 YAO Shu-chun XUE Bin XIA Wei-lan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第2期402-406,共5页
Vertical profiles of the total organic carbon (TOC), total nitrogen (TN), phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, Ch... Vertical profiles of the total organic carbon (TOC), total nitrogen (TN), phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, China. The average sedimentation rate was 1.55 mm/a. The results indicated that trophic status of Honghu Lake in the historical period had experienced three stages. Before 1840 the lake was characterized with lower productivity, TOC was less than 9.92 g/kg; TN was 0.902 to 1.24 g/kg. During about 1840-1950, population increased quickly, there was an obvious change in TOC with an average of 13.0 g/kg. Since 1950, human impacts have accelerated the lake eutrophication and nutrients enriched in the sediment with TOC of 21.7 to 93.1 g/kg, TN of 1.77 to 8.78 g/kg. The heavy metal concentration profiles presented similar distribution trends except Pb .and Mn. The results from elements analyses indicated that Honghu Lake had not been polluted by heavy metals except lead. 展开更多
关键词 Honghu Lake lake deposit human impact
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Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010 被引量:5
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作者 LIU Qinping YANG Yongchun +2 位作者 TIAN Hongzhen ZHANG Bo GU Lei 《Chinese Geographical Science》 SCIE CSCD 2014年第2期231-244,共14页
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment espec... Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China. 展开更多
关键词 vegetation change human impact urbanization built-up areas nighttime light data Normalized Difference Vegetation Index(NDVI)
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Micro-site Conditions of Epiphytic Orchids in a Human Impact Gradient in Kathmandu Valley, Nepal 被引量:2
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作者 Yagya Prasad ADHIKARI Anton FISCHER Hagen Siegfried FISCHER 《Journal of Mountain Science》 SCIE CSCD 2012年第3期331-342,共12页
We studied distribution and site conditions of epiphytic orchids in a gradient of human interference in Kathmandu valley, central Nepal. The aim was to understand the recent distribution pattern of epiphytic orchids, ... We studied distribution and site conditions of epiphytic orchids in a gradient of human interference in Kathmandu valley, central Nepal. The aim was to understand the recent distribution pattern of epiphytic orchids, with respect to (i) the micro-site conditions and (ii) the type and intensity of land use. The occurrence of epiphytic orchids was recorded for a grid with 1.5 km cell size. The cells represent different types and intensities of human impact. Site factors such as bark rugosity, bark pH, diameter at breast height (dbh; 1.3 m) of host trees, exposure to wind and sunlight intensity were recorded. With regard to the species richness and abundance of epiphytic orchids, we compared different human impact categories from very strong human impact (settlement area) to very low human impact (national park). Remote sensing was used for a supervised classification of land cover. Ficus religiosa turned out to be the most important host species for orchids in urban areas, while Schima wallichii and Alnus nepalensis significantly host orchids in the other categories. Both species richness and abundance of epiphytic orchids were significantly higher under very low human impact (forest in national park) and also some remaining patches of primary forest than the other regions. Micro-climate is crucial for orchid populations. Host bark pH, bark rugosity, sunlight intensity and host exposure were significantly different for all human impact categories in order to harbour epiphytic orchid species. Habitats with a mixture of mature trees are suitable and essential for the conservation of viable populations of epiphytic orchids in settled areas. The study reveals that to improve the population size of orchids it is essential for future urban forestry to: (i) Protect old trees as carriers of existing epiphytic orchid diversity, (ii) protect medium old trees to ensure that they may become old trees, (iii) plant new host trees for the future, (iv) plant in groups instead of single isolate trees. Trees should especially be planted in areas where orchids still exist to provide more trees for orchid population enlargement (e.g. along riparian system). Native species should be favoured; the pool of such native host species is wide. 展开更多
关键词 human impact Host tree Micro-climate Epiphytic orchids Remote sensing CONSERVATION Nepal
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Human impacts on the terrestrial ecosystem of Fildes Peninsula of King George Island, Antarctica
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作者 ZHAO Ye\+1, XU Cui\|hua\+2 (1. Institute of Resource and Environmental Sciences, Beijing Normal University, Beijing 100875, China 2. Laboratory of Industrial Hygiene, Ministry of Public Health, Beijing 100088, China) Foundation item: National Natur 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第1期14-19,共6页
Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based o... Antarctic environment has valuable baseline information for understanding the global change. The objectives of this study were to investigate the impacts of human activities on Antarctic terrestrial ecosystem. Based on the investigation results and the sampling analysis of the environment of Fildes Peninsula, King George Island, Antarctica, it was shown that there are some artificial radioactive elements—? ? 137 Cs in Antarctic environment: the radioactivity of 137 Cs in the surface soil, the surface moss, the fruticose lichen and the crustaceous lichen are 6 00—14 80, 25 07, 29 04 and 58 07 Bq/kg separately; i.e. the sequence of 137 Cs specific activity is as follows: crustaceous lichen>fruticose lichen>surface moss>surface soil, which demonstrates that the crustaceous lichen is one of the most sensitive monitor ways for the effect of the long term diffusion of 137 Cs. The impacts of the scientific research activities on the partial ecosystem of Fildes Peninsula include: the changes of the landscape and the soil material have made a strong freezing thawing process, which decreases the stability of the ground surface, causes the degradation of the vegetation in the some small areas; some small lakes, runoff and lichens in middle areas of Fildes Peninsula have been affected by the wastes of the stations, in the surrounding areas of the expedition stations, the concentration of Cr, Cu, Ni, Pb and Zn in the lichen and the water are higher than that of the contrasting area. Fildes Peninsula is one of the most crowded areas of expedition stations, at some extent, the environment and terrestrial ecosystem have been affected by the human activities. The conservation of the environment and ecosystem should be an important aspect of Antarctic environmental sciences. 展开更多
关键词 ANTARCTICA Fildes Peninsula terrestrial ecosystem human impacts CLC number: X21 Document code: A
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Genetic diversity of Mansonia altissima A. Chev. under different regimes of human impact in the Akure Forest Reserve,Nigeria
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作者 Akindele AKINNAGBE Oliver GAILING Reiner FINKELDEY 《Forestry Studies in China》 CAS 2010年第4期193-200,共8页
Mansonia altissima is an important West African timber tree species. For the purpose of examining the effect of human impact on its genetic diversity, genetic diversity and spatial genetic structure of the species und... Mansonia altissima is an important West African timber tree species. For the purpose of examining the effect of human impact on its genetic diversity, genetic diversity and spatial genetic structure of the species under different regimes of human impact were investigated in the Akure Forest Reserve, Nigeria, using 504 amplified fragment length polymorphism (AFLP) markers. The results indicate a very low genetic diversity in M. altissima within the forest reserve (He = 0.045; PPL = 16.75%; Br = 1.162). The highest genetic diversity was observed in the primary forest (H e= 0.062; PPL - 21.00%; Br = 1.204), with the lowest genetic diversity in the isolated forest patch (He = 0.032; PPL = 9.00%; B r= 1.089). A significant and pronounced spatial genetic structure was found in the logged forest and in the isolated forest patch. In contrast, the primary forest exhibited very weak spatial genetic structuring. As expected, no spatial genetic structure was found in the planted stands of M. altissima. From a conservation point of view, our results suggest that genetic diversity ofM. altissima is at risk in the forest reserve. The scale of human impact in the study area could pose a serious threat to the maintenance of genetic diversity of the species. These results would offer practical applications in the conservation of other tropical tree species. 展开更多
关键词 AFLP Mansonia altissima human impact genetic diversity spatial genetic structure tropical rainforests
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Impact of Plastic Waste on the Human Health in Low-Income Countries: A Systematic Review
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作者 Ramde Wendkoaghenda Sophie Gbandama Koffi Kouame Pacome +5 位作者 Gansore Aminata Camara Kelety Tolno Barthélemy Assogba Ange Wenceslas Vinciale Niare Boubacar Patrice Ngangue 《Journal of Environmental Protection》 2024年第5期572-595,共24页
Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pol... Background: Plastic pollution is the accumulation of waste composed of plastic and its derivatives all over the environment. Whether in the form of visible garbage or microparticles, as it slowly degrades, plastic pollution poses significant threats to terrestrial and aquatic habitats and the wildlife that call them home, whether through ingestion, entanglement or exposure to the chemicals contained in the material. Unfortunately, there is a lack of documentation on the impact of plastic waste on human health in low- and middle-income countries (LMICs). Methods: We searched five electronic databases (PubMed, Embase, Global Health, CINAHL and Web of Science) and gray literature, following the preferred reporting elements for systematic reviews and meta-analyses (PRISMA), for the impact of plastic waste on human health in developing countries. We included quantitative and qualitative studies written in English and French. We assessed the quality of the included articles using the Mixed Methods Appraisal tool (MMAT). Results: A total of 3779 articles were initially identified by searching electronic databases. After eliminating duplicates, 3167 articles were reviewed based on title and abstract, and 26 were selected for full-text review. Only three articles were retained. The three articles dealt with practices likely to lead to oral exposure to plastic chemicals in human health, as well as the level of awareness of participants concerning the possible impact of plastic on human health, namely, the use of plastic baby bottles, the use of microwaves to cook food and reheat precooked food, the use of plastic bottles to store water in the refrigerator, water purifier containers with plastic bodies and plastic lunch boxes, the reuse of plastic bags and the inadequacy of treatment facilities. Conclusion: Plastic waste poses different risks to human health at every stage of its life cycle. Hence, strategies must be adopted to raise public awareness of the dangers of plastic waste to their health. Trial registration: The review protocol is registered in the PROSPERO international prospective register of systematic reviews (ID = CRD42023409087). 展开更多
关键词 human Population Plastic Waste Health impact Low-Income-Countries (humans Iatrogenic Disease PLASTICS POLICY RECYCLING Waste Management)
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Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan
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作者 Abdallah Gordon Shazali Joseph Mayindo Mayele +1 位作者 Joel Emmanuel Saburi Jubara Nadlin 《Open Journal of Ecology》 2024年第5期483-507,共25页
Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habi... Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the Kruskal Wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-Weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human footprints and tree cutting combined accounted for 9%, indicating the practice of livestock grazing, poaching, encroachment, and fuelwood collection by local communities. However, these activities did not appear to significantly impact the diversity, abundance, and distribution of large mammals in Nimule National Park. Therefore, it is crucial to foster shared responsibilities and engage relevant stakeholders in the management and conservation of large wildlife species. Regular community awareness programs should be implemented to cultivate a sense of ownership. Moreover, it is recommended that a comprehensive survey be conducted on the population status of all mammal species in Nimule National Park, including its surrounding Buffer Zone. Monitoring the impact of human activities on their behavior and habitats using satellite images should also be carried out at least every five to ten years. 展开更多
关键词 Diversity of Large Mammals Abundance and Distribution impactS Biodiversity Conservation human Activities Nimule National Park South Sudan
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Cumulative human impacts in the Bering Strait Region
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作者 Jamie C.Afflerbach Dan Yocum Benjamin S.Halpern 《Ecosystem Health and Sustainability》 SCIE 2017年第8期1-14,共14页
Introduction:Human impacts on Arctic marine ecosystems are increasing in extent and intensity as sea ice shrinks and utilization of marine resources expands.The effects of climate change are being felt across the arct... Introduction:Human impacts on Arctic marine ecosystems are increasing in extent and intensity as sea ice shrinks and utilization of marine resources expands.The effects of climate change are being felt across the arctic while stressors such as commercial fishing and shipping continue to grow as the Arctic becomes more accessible.Given these emerging changes,there is need for an assessment of the current cumulative impact of human activities to better anticipate and manage for a changing Arctic.Cumulative human impacts(CHI)assessments have been widely applied around the world in a variety of ecosystem types but have yet to incorporate temporal dynamics of individual stressors.Such dynamics are funda-mental to Arctic ecosystems.Outcomes:Here,we present the first CHI assessment of an Arctic ecosystem to incorporate sea ice as a habitat and assess impact seasonality,using the Bering Strait Region(BSR)as a case study.We find that cumulative impacts differ seasonally,with lower impacts in winter and higher impacts in summer months.Large portions of the BSR have significantly different impacts within each season when compared to a mean annual cumulative impact map.Cumulative impacts also have great spatial variability,with Russian waters between 2.38 and 3.63 times as impacted as US waters.Conclusion:This assessment of seasonal and spatial cumulative impacts provides an under-standing of the current reality in the BSR and can be used to support development and evaluation of future management scenarios that address expected impacts from climate change and increasing interest in the Arctic. 展开更多
关键词 Arctic marine ecosystems cumulative human impacts Bering Strait sea ice limate change
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Surface pollen assemblages as indicators of human impact in the warm temperate hilly areas of eastern China 被引量:7
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作者 DING Wei PANG RuiMing XU QingHai LI YueCong CAO XianYong 《Chinese Science Bulletin》 SCIE EI CAS 2011年第10期996-1004,共9页
Investigation of 78 surface pollen samples from warm temperate hilly areas of eastern China shows that pollen assemblages in areas of different land use are significantly different.Pollen concentrations in wastelands ... Investigation of 78 surface pollen samples from warm temperate hilly areas of eastern China shows that pollen assemblages in areas of different land use are significantly different.Pollen concentrations in wastelands are higher than in plantations;these,in turn,are higher than in farmlands;implying that pollen concentration decreases with increasing human impact.Arboreal pollen dominated by Pinus and Quercus is common in all samples.Herbaceous pollen percentages are higher while shrub pollen,fern spores and fern allies are lower in farmlands than in wastelands.Crop pollen is only detectable in and near farmlands;its percentages and concentrations decrease in wastelands.Cereal and Cruciferae pollen percentages average 16.7% and 6.7% in farmland respectively,but Cereal reduces to less than 3% and Cruciferae to less than 0.5% in nearby wastelands.Principle coordinates analysis and clustering analysis indicate that pollen assemblages from farmlands are distinguishable from those under other vegetation types.Occurrence of Poaceae,Chenopodiaceae,Artemisia,and Compositae pollen and Selaginella sinensis spores are closely related to human activities,and their types and frequencies indicate intensity of human impact.The spatial distribution of crops,Chenopodiaceae,and Artemisia reflects changes in both natural environments and human activities.Percentages of cereal and Cruciferae pollen,for example,increase with decreasing altitude,but decrease with increasing latitude.Understanding pollen assemblages under artificial and human-disturbed vegetation in hilly areas may aid understanding of human impacts on the plains during the early-middle Holocene. 展开更多
关键词 丘陵地区 中国东部 人类影响 暖温带 孢粉 地表 花粉浓度 十字花科
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Holocene grassland vegetation, climate and human impact in central eastern Inner Mongolia 被引量:8
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作者 HUANG Fei1, Kealhofer Lisa2, XIONG Shangfa3 & HUANG Fengbao1 1. Nanjing Institute of Geology and Paleontology,Chinese Academy of Sciences,Nanjing 210008,China 2. Anthropology and Sociology Department,Santa Clara University,CA 95053,USA 3. Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 《Science China Earth Sciences》 SCIE EI CAS 2005年第7期1025-1039,共15页
Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen rec... Phytolith and pollen preserved in the Taipusi Banner paleosol profile, central eastern Inner Mongolia, provide evidence of Holocene grassland vegetation, climate and human impact. The combined phytolith and pollen records reveal a major change in vegetation composition about 5000 a BP. Before 5000 a BP, the vegetation was dominated by Aneurolepidium Chinese-Stipa grandis grassland of C4 grasses. After 5000 a BP, C4 grasses rapidly retreated, indicating a shift to colder and more arid conditions. The gradual invasion of Stipa krylovii, Ag-ropyron desertorum, Ephedra, Chenopodiaceae and Caragana reveal the onset of grassland degeneration. Between 10000 and 8720 a BP, the Aneurolepidium Chinese-Stipa grandis grassland included a small proportion of Artemisia shrub and Echionopos type plants, implying a strong winter monsoon and very weak summer monsoon. From 8720 to 7000 a BP, C4 grasses were common, indicating a strengthening of the summer monsoon. Between 7000 and 5000 a BP, the Holocene thermal maximum was evident, with a significant expansion of C4 grasses and the presence of some trees (such as Pinus and Betula, and so on) in or near the study site. From 4200?000 a BP, a sandy grassland of Artemisia and Agropyron desertorum together with Aster-type taxa occurred. Precipitation amelioration took place between 3000 and 2170 a BP, with a rapid development of Echinops type plants and a small expansion of C4 grasses. From 2170 a BP to present, human activities accelerated the process of grassland degeneration. 展开更多
关键词 PHYTOLITH and POLLEN records grassland environment change human impact HOLOCENE CENTRAL EASTERN Inner Mongolia.
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Reconstruction of cultivated land during mJid- Holocene in the middle and lower reaches of Yellow River and human impact on vegetations 被引量:1
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作者 HOU Guangliang LAI Zhongping +1 位作者 XIAO Jingyi E Chongyi 《Journal of Geographical Sciences》 SCIE CSCD 2012年第5期933-945,共13页
Yangshao culture is the most important mid-Holocene Neolithic culture in the Yellow River catchment, and thus, a study on the impact of human activities on the environment is important. In the current study, the distr... Yangshao culture is the most important mid-Holocene Neolithic culture in the Yellow River catchment, and thus, a study on the impact of human activities on the environment is important. In the current study, the distribution pattern of the cultivated land in late Yangshao culture is reconstructed using GIS tool and site domain analysis (SDA). The results show that the cultivated land during 5.5-5.0 ka BP was mainly distributed in the Weihe River valley, Luohe River valley, northwestern Henan Plain, Fenhe River valley and eastern Gansu region, especially concentrated in the Xi'an-Baoji line of the Weihe River valley. At that time, at least 37,000 km2 of lands were reclaimed in the middle and lower reaches of the Yellow River, and 132,000 km2 of lands were affected by agricultural activities. Human activities had become the driving force of land use/land coverage. Charcoal records indicate that the ancestors of Yangshao culture burnt forests for reclamation, leading to the decrease of arbor pollen at 5 ka BP in core areas of the Yangshao culture. The areas that were significantly affected by human activities accounted for 3.2% of the Yangshao culture influenced area, while the moderately affected areas accounted for 20.1% of Yangshao culture influenced area. Meanwhile, 92% of the land areas on the edge and outside of the Yangshao culture influenced area were not affected by human activities. The arbor pollen in these areas did not decrease until 4.0 ka BP. 展开更多
关键词 MID-HOLOCENE Yangshao culture cultivated land human activity and its impact on environment themiddle and lower reaches of the Yellow River
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Health and Economic Impacts of Air Pollution in China: A Comparison of the General Equilibrium Approach and Human Capital Approach 被引量:7
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作者 YUE WAN HONG-WEI YANG TOSHIHIKO MASUI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第6期427-441,共15页
In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the... In China, combustion of fossil fuels and biomass has produced serious air pollution that does harm to human health. Based on dose-response relationships derived from epidemiological studies, the authors calculated the number of deaths and people with health problems which were thought to be attributable to China's air pollution in the year of 2000. In order to estimate the corresponding economic impacts from the national point of view, the general equilibrium approach was selected as an analysis tool for this study. A computable general equilibrium (CGE) model was constructed involving 39 sectors and 32 commodities. The human capital approach (HCA) was also used for comparison. The economic burden of disease for people estimated by HCA was equivalent to 1.26‰ (ranging from 0.44‰ to 1.84‰) of China's gross domestic product (GDP). China's GDP loss estimated by the general equilibrium approach reached 0.38‰ (ranging from 0.16‰ to 0.51‰). The difference between the two approaches and the implications of the results were discussed. 展开更多
关键词 Air pollution HEALTH Economic impact CGE model human capital approach
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Study on the Spreading of Environmental Impact of Human Being' s Activities and Its Crucial Factors in Upper Minjiang River 被引量:1
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作者 FanHong ZhaoHong-da 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期949-956,共8页
This paper focuses on the historical transition of human being's activities and the eco-environment in the upper reaches of Minjiang River. The history is divided into 4 periods, each with its own feature. During ... This paper focuses on the historical transition of human being's activities and the eco-environment in the upper reaches of Minjiang River. The history is divided into 4 periods, each with its own feature. During the period of nomad immigration, the top-line of the subalpine forest was forced downward by the expanding subalpine meadow. During the period of farming nationality immigration, the bottom-line of middle mountain forest had moved upward forced by the needs for land or timber of the increasing population in the valley basia During the period of the early exploiting, the focus resource was the timber. The total output was limited, comparing with the later period, because of the bad accessibility. But it was large enough to impact the forest ecosystem of the deforesting area. The recent 50 years is the crucial period of economic development and eco-environment degradation. This paper points out that the impact of human being's activities for environment lies on 3 factors: 1) physical features control the location and tendency eco-environmental change; 2) population and productivity control the scale and speed of eco-environmental change; 3) regional accessibility controls the time and location of eco-environmental change. 展开更多
关键词 historical period human being's activities environmental impact crucial factors
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Impacts of human activities on water cycles in Haihe Basin
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作者 LI Lijuan Institute of Geography, Chinese Academy of Sciences, Beijing 100101 CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第3期105-109,共5页
This paper studies effects of human activities on water cycle in Haihe basin, focusing on the effects on the key elements of water balance and environmental issues caused by unreasonable water development and utilizat... This paper studies effects of human activities on water cycle in Haihe basin, focusing on the effects on the key elements of water balance and environmental issues caused by unreasonable water development and utilization. The water cycle system becomes closer than in nature with the river runoff decrease and evapotranspiration increase. River runoff reduction, groundwater over-exploitation, and water pollution have caused a series of environmental problems in the area. The main issues are river dried up, sedimentation and salt accumulation, groundwater depression, land subsidence, sea water intrusion, as well as water pollution. The author believes that the highest level of water development should below 50 percent as a whole. The best way to meet increasing water demands of human activities is to raise efficiency of water resources use. Meanwhile waste water discharge should be reduced through treatment and recycle technology. 展开更多
关键词 impactS human activity water cycle Haihe basin
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The impact of HDL in human blood on acute toxicity of mice
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《中国输血杂志》 CAS CSCD 2001年第S1期424-,共1页
关键词 HDL The impact of HDL in human blood on acute toxicity of mice
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基于任务清单的柔性拔牙CBL病例资料库的构建与应用价值
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作者 于鸿滨 易春艳 +3 位作者 殷凌云 黄燕飞 李昌全 欧阳骞 《云南医药》 CAS 2024年第3期47-49,共3页
目的 探讨基于任务清单的柔性拔牙CBL病例资料库的构建与应用。方法 本研究在开展柳传志环(PDF环)结合“以病例为引导”的教学法应用于牙槽外科临床带教的基础上,选择阻生牙微创拔除术为经典案例,应用于临床带教,开展柔性拔牙临床医学... 目的 探讨基于任务清单的柔性拔牙CBL病例资料库的构建与应用。方法 本研究在开展柳传志环(PDF环)结合“以病例为引导”的教学法应用于牙槽外科临床带教的基础上,选择阻生牙微创拔除术为经典案例,应用于临床带教,开展柔性拔牙临床医学人文教育。结果 构建基于任务清单的柔性拔牙CBL病例资料库具有较强的临床实用性和较好的客观性,对实习医师医学人文素养的培育、临床思维能力的培养、自我学习能力的激发、发散思维模式的训练、知识体系的逻辑性归纳等方面有着明显优势。结论 本研究基于任务清单的柔性拔牙CBL病例资料库的构建具有较大的优势,能够使其成为带教教师不断学习和临床带教的手段,值得广泛应用于临床实习带教。 展开更多
关键词 任务清单 柔性拔牙 病例资料库 阻生牙 医学人文教育
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学术成果宏观评价的新探索——评《中国人文社科成果的国际影响力研究》
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作者 叶继元 陶蕊 《图书馆杂志》 CSSCI 北大核心 2024年第6期40-42,48,共4页
构建公正合理的学术评价体系是学术研究健康发展的要旨。加强中国人文社科学术成果国际影响力评价研究,不仅有利于我国人文社科学术研究的发展,还有助于弘扬中华文化,提高国家文化软实力和国际话语权。武汉大学杨思洛教授等的新作《中... 构建公正合理的学术评价体系是学术研究健康发展的要旨。加强中国人文社科学术成果国际影响力评价研究,不仅有利于我国人文社科学术研究的发展,还有助于弘扬中华文化,提高国家文化软实力和国际话语权。武汉大学杨思洛教授等的新作《中国人文社科成果的国际影响力研究》一书结构系统,内容翔实,系统地讨论了中国人文社科成果国际影响力评价这一主题,在理论研究、评价方法和学术观点方面均有新意,是学术成果宏观评价的新探索。 展开更多
关键词 人文社科 学术成果 国际影响力 学术评价
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基于ImPACT等式的人类活动环境影响分析——以甘肃省虚拟水消费为例 被引量:11
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作者 焦文献 徐中民 +1 位作者 尚海洋 程怀文 《冰川冻土》 CSCD 北大核心 2006年第5期748-754,共7页
应用ImPACT等式,分析了甘肃省1990—2003年虚拟水消费中人类活动对环境的影响.结果表明:相比1990—1995年,1996—2000年和2001—2003年甘肃省收入显著提高,而使用强度(单位GDP的农产品消费量)和效率(单位农产品消耗的虚拟水量)大幅度改... 应用ImPACT等式,分析了甘肃省1990—2003年虚拟水消费中人类活动对环境的影响.结果表明:相比1990—1995年,1996—2000年和2001—2003年甘肃省收入显著提高,而使用强度(单位GDP的农产品消费量)和效率(单位农产品消耗的虚拟水量)大幅度改善,对环境影响(虚拟水消费量)起到了调节作用.收入弹性分析表明,收入增加1%将引起人均农产品消费量增加0.13%,使用强度下降0.87%,而环境影响增加0.14%.2000年甘肃省城镇和农村虚拟水消费对比分析表明,农村的虚拟水强度(0.706 m3.元-1)显著高于城镇(0.051 m3.元-1),合理改善消费结构能降低虚拟水强度从而减轻对环境的影响.应用ImPACT等式设置环境目标并检验其可行性,结果表明:在1990—2003年的基础上,使用强度降低1.5倍,效率提高1倍,能够保障经济的增长,并在合理的时间范围内(28 a)实现虚拟水消费量减少到2003年的50%,是一种可行的选择方案. 展开更多
关键词 环境影响 人类活动 IPAT等式 impact等式 虚拟水
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塑料颗粒对人体健康影响的研究进展
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作者 冯亚慧 李灼 李文静 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第9期1310-1317,共8页
随着塑料制品在全球的大量使用,塑料污染日趋严重,由塑料破碎形成的塑料颗粒近年来受到广泛关注。塑料颗粒的来源多种多样,可以通过呼吸道吸入、消化道摄入、皮肤直接接触等方式进入人体,再通过氧化应激、炎症反应等机制对人体多个系统... 随着塑料制品在全球的大量使用,塑料污染日趋严重,由塑料破碎形成的塑料颗粒近年来受到广泛关注。塑料颗粒的来源多种多样,可以通过呼吸道吸入、消化道摄入、皮肤直接接触等方式进入人体,再通过氧化应激、炎症反应等机制对人体多个系统造成影响;另外,塑料颗粒还可与添加剂、重金属、细菌、病毒等有毒污染物共暴露,对人体产生影响。文章从塑料颗粒的定义、来源、进入人体的方式、检测方法以及对人体各个系统的影响进行总结,为后续防治塑料污染以减少塑料颗粒对人体的有害影响提供思路。 展开更多
关键词 塑料颗粒 微塑料 纳米塑料 人体健康 影响
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