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Spatial distribution patterns of wetland plants in relation to environmental gradient in the Honghe National Nature Reserve, Northeast China 被引量:4
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作者 ZHOU Demin LUAN Zhaoqing +1 位作者 GUO Xiaoyu LOU Yanjing 《Journal of Geographical Sciences》 SCIE CSCD 2012年第1期57-70,共14页
Quantifying correlation between the spatial patterns of natural wetland plants and environmental gradient gives better understanding of wetland habitats, which is the fundamental for the strategy making on the protect... Quantifying correlation between the spatial patterns of natural wetland plants and environmental gradient gives better understanding of wetland habitats, which is the fundamental for the strategy making on the protection and restoration of natural wetlands. In this study, the spatial patterns of wetland plants and the environmental gradient of wetland habitats were assessed in the Honghe National Nature Reserve (HNNR) in Northeast China, a wetland of international importance on the Ramsar list. Biophysical parameters’ values of wetland plants were obtained by field sampling methods, and wetland mapping at the community scale was completed using remote sensing techniques. Digital delineation of the surface water system, hydrological zoning and wetness index were produced by spatial analysis methods in Geographic Information System. An ecological ordination method and two clustering methods were used to quantify the relationship between the spatial distribution patterns of wetland plants and the corresponding environmental gradients. Such quantitative analyses also present the specific diversity of different types of wetland plants based on the environmental attributes of their habitats. With the support from modern geo-information techniques, the experimental results indicate how four ecotypes of wetland plants spatially transit from forest swamp, shrub wetland and meadow into marsh wetland with increasing wetness index and water table. And they also show how wetland spatial distribution patterns are controlled by an environmental gradient of wetness. Another key finding of this research work is that our results present the exact fundamental differences between marsh and non-marsh plants of 11 wetland plant communities within the core study area. Hence, this case study gives a good sample for better understanding of the complex correlation between the spatial patterns of wetland plants and their environmental attributes using advanced digital analysis methods. It is also useful to show how to integrate geoinformatic techniques with statistical analysis methods based on the field data base. 展开更多
关键词 WETLAND plant ecology spatial pattern environmental gradient Honghe National Nature Reserve
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Chemometric study of spatial variations of environmental and ecological characteristics in the Zhujiang River (Pearl River) Estuary and adjacent waters 被引量:6
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作者 SONG Xingyu HUANG Liangmin +4 位作者 ZHANG Jianlin YIN Kedong LIU Sheng TAN Yehui YIN Jianqiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第4期60-74,共15页
Chemometric approach based on principal component analysis(PCA) was utilized to examine the spatial variances of environmental and ecological characteristics in the Zhujiang River(Pearl River) Estuary and adjacent... Chemometric approach based on principal component analysis(PCA) was utilized to examine the spatial variances of environmental and ecological characteristics in the Zhujiang River(Pearl River) Estuary and adjacent waters(ZREAW) in the South China Sea. The PCA result shows that the ZREAW can be divided into different zones according to the principal components and geographical locations of the study stations,and indicates that there are distinct regional variances on environmental features and the corresponding phytoplankton biomass and community structures among different areas. The spatial distribution of ecological features was implied to be influenced by various degrees of the different water resources,such as the Pearl River discharges,the coastal current and the oceanic water from the South China Sea. The variation of the biomass maximum zone and the complex impacts on the spatial distributions of phytoplankton biomass and production were also evaluated. 展开更多
关键词 principal component analysis spatial variations environmental conditions ecological distribution PHYTOPLANKTON Zhujiang River (Pearl River) Estuary
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Types, Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in China 被引量:6
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作者 Wang Zhitian and Qin Kezhang Beijing Institute of Geology for Mineral Resources, CNNC, Beijing Zhang Zhongmin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1989年第1期79-92,共14页
Based upon a comprehensive study of 123 copper deposits in China. this paper reaches the following conclusions: 1. The crust in China was solidified pretty late; with the accretion of the plate, the copper mineralizat... Based upon a comprehensive study of 123 copper deposits in China. this paper reaches the following conclusions: 1. The crust in China was solidified pretty late; with the accretion of the plate, the copper mineralization moved towards its margin in space and became successively younger in age. 2. The major copper ore types ever found in the world have mostly been discovered in China, in which the porphyry type seems to be the most important and the massive sulfide type in the transitional bed between marine clastic and carbonate rocks is clearly defined. 3. Carbonate strata are widespread in China and their deposition lasted for a long geological period, so the proportion of copper deposits occurring in them is large as compared with other parts of the world. 4. Seven metallogenic epochs can be recognized, in which the Mesozoic one plays the leading role and the middle(late) Palaeozoic and Cenozoic ones are next in importance. Mineralization was comparatively simple in the early geological period. and became diversified later on. In the early epochs copper deposits related to basaltic magmatism and metamorphosed marine sediments predominated, whereas in the later epochs those related to granitic magmatism and continental sedimentation were dominant. 5. There exist in China thirteen metallogenic provinces, of which the Lower Yangtze downwarping belt, Sanjiang fold system, Jiangnan axis and Xikang-Yunnan axis are of greater significance. 6. The crustal mobility in China was rather pronounced, the polycyclic evolution of the crust has resulted in such obvious phenomena as the inheritance of mineralization, the coexistence of various types and the superposition of different genetic types. 展开更多
关键词 Metallogenic environments and Characteristics of Temporal and spatial Distribution of Copper Deposits in China TYPES
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Influence of Spatial-Temporal and Environmental Factors on Larimichthys polyactis, Octopus variabilis, and Species Aggregated Set-Net CPUEs in Haizhou Bay, China 被引量:3
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作者 TANG Yanli MA Shuyang +2 位作者 LIU Changdong WANG Xinmeng CHENG Shasha 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期973-982,共10页
Set-nets are common alongshore fishing gear used in Haizhou Bay, which rely on flow to catch fish. The catch per unit effort(CPUE) of set-net is affected by spatial-temporal and environmental factors but no research h... Set-nets are common alongshore fishing gear used in Haizhou Bay, which rely on flow to catch fish. The catch per unit effort(CPUE) of set-net is affected by spatial-temporal and environmental factors but no research has been conducted on this subject. In this study, we used generalized additive models(GAMs) to explore the influence of spatial-temporal and environmental factors on CPUEs of species aggregated, small yellow croaker(Larimichthys polyactis), and octopus(Octopus variabilis) based on logbooks investigations conducted at 4 stations in an alongshore area of Haizhou Bay from 2011 to 2012. The results showed that all CPUEs exhibited significant spatial-temporal differences at various scales. Aggregated CPUE was high when the sea surface temperature(SST) was 15-18℃ and 20-23℃, which was mainly determined by life history traits of the octopus and small yellow croaker(optimal SSTs 14-17℃ and 19-24℃, respectively). Chlorophyll-a concentration had significant influences on the aggregated, small yellow croaker and octopus CPUEs at optimal ranges of 3.8-6.2 mg m^(-3), 4.2-4.8 mg m^(-3) and 4.5-5.5 mg m^(-3), respectively. Flow through the net had positive relationships with CPUEs. The approximate logarithmic trends in regression curves had a critical point of 2.5 Mm^3 d^(-1), which was the dividing point that differentiated whether the major factor affecting CPUEs was the flow velocity or the fishery resource. Our results from this study will help guide fishery production and improve catch rate of set-net fishing in Haizhou Bay. 展开更多
关键词 spatial-temporal environmental factors set-net small YELLOW CROAKER OCTOPUS generalized additive models Haizhou BAY
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Spatial Design Strategies for Community Parks Based on Environmental Perception 被引量:1
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作者 YANG Liuqing YI Keqian 《Journal of Landscape Research》 2012年第12期1-2,共2页
By applying environmental perception theories, spatial configurations of community parks were analyzed, and spatial design strategies meeting perceptual psychology of users were proposed to integrate the community par... By applying environmental perception theories, spatial configurations of community parks were analyzed, and spatial design strategies meeting perceptual psychology of users were proposed to integrate the community park environment into daily life of local residents, and create a harmonious and vital living environment. 展开更多
关键词 COMMUNITY PARK spatial design environmentAL PERCEPTION Behavior and PSYCHOLOGY
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Spatial and historical distribution of organic phosphorus driven by environment conditions in lake sediments 被引量:3
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作者 Changwei Lü Jiang He Bing Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第2期32-41,共10页
The chemistry of sedimentary organic phosphorus(OP) and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with enviro... The chemistry of sedimentary organic phosphorus(OP) and its fraction distribution in sediments are greatly influenced by environmental conditions such as terrestrial inputs and runoffs. The linkage of OP with environmental conditions was analyzed on the basis of OP spatial and historical distributions in lake sediments. The redundancy analysis and OP spatial distribution results suggested that both Na OH-OP(OP extracted by Na OH) and Re-OP(residual OP) in surface sediments from the selected 13 lakes reflected the gradient effects of environmental conditions and the autochthonous and/or allochthonous inputs driven by latitude zonality in China. The lake level and salinity of Lake Hulun and the runoff and precipitation of its drainage basin were reconstructed on the basis of the geochemistry index. This work showed that a gradient in weather conditions presented by the latitude zonality in China impacts the OP accumulation through multiple drivers and in many ways.The drivers are mainly precipitation and temperature, governing organic matter(OM)production, degradation rate and transportation in the watershed. Over a long temporal dimension(4000 years), the vertical distributions of Re-OP and Na OH-OP based on a dated sediment profile from HLH were largely regulated by the autochthonous and/or allochthonous inputs, which depended on the environmental and climate conditions and anthropogenic activities in the drainage basin. This work provides useful environmental geochemistry information to understand the inherent linkage of OP fractionation with environmental conditions and lake evolution. 展开更多
关键词 Organic phosphorus spatial and historical distribution environmental conditions SEDIMENT LAKE
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Spatial distributions of tropical tree species in northern Vietnam under environmentally variable site conditions 被引量:6
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作者 Nguyen Hong Hai Kerstin Wiegand Stephan Getzin 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期257-268,共12页
Ecological interactions of species and thus their spatial pat- terns may differ between homogeneous and heterogeneous forests. To account for this, techniques of point pattern analysis were implemented on mapped locat... Ecological interactions of species and thus their spatial pat- terns may differ between homogeneous and heterogeneous forests. To account for this, techniques of point pattern analysis were implemented on mapped locations of tree individuals from two 1-ha tropicalforest plots in Vietnam. We analyzed the effect of environmental heterogeneity on tree distributions; spatial distribution patterns of dominant species; inter-specific associations; and conspecific associations between life stages. Our analyses showed that: environmental conditions were homo- geneous at plot 1 but heterogeneous at plot 2; in both plots, all six domi- nant species were aggregated at various scales up to 30 m, and tree spe- cies were aggregated at larger scales in the homogeneous site than in the heterogeneous site; attraction between pairs of species was remarkably higher at the homogeneous site while negative associations were more frequent in the heterogeneous site; some species, H. kurzii, T. ilicifolia (homogeneous plot) and D. sylvatica, S. wightianum (heterogeneous plot) showed a lack of early life-stage individuals near conspecific adults. Moreover, additional clustering of young individuals was independent from conspecific adults, except D. sylvatica in both sites. These findings are consistent with the Janzen-ConneU hypothesis. Overall, habitat het- erogeneity influences spatial patterns and inter-specific associations of the tree species and evidences of self-thinning are shown in most species. 展开更多
关键词 environmental heterogeneity spatial point pattern analysis tropical evergreen forest northern Vietnam.
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Combining Environmental Factors and Lab VNIR Spectral Data to Predict SOM by Geospatial Techniques 被引量:3
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作者 GUO Long ZHANG Haitao +1 位作者 CHEN Yiyun QIAN Jing 《Chinese Geographical Science》 SCIE CSCD 2019年第2期258-269,共12页
Soil organic matter(SOM) is an important parameter related to soil nutrient and miscellaneous ecosystem services. This paper attempts to improve the performance of traditional partial least square regression(PLSR) mod... Soil organic matter(SOM) is an important parameter related to soil nutrient and miscellaneous ecosystem services. This paper attempts to improve the performance of traditional partial least square regression(PLSR) model by considering the spatial autocorrelation and soil forming factors. Surface soil samples(n = 180) were collected from Honghu City located in the middle of Jianghan Plain, China. The visible and near infrared(VNIR) spectra and six environmental factors(elevation, land use types, roughness, relief amplitude, enhanced vegetation index, and land surface water index) were used as the auxiliary variables to construct the multiple linear regression(MLR), PLSR and geographically weighted regression(GWR) models. Results showed that: 1) the VNIR spectra can increase about 39.62% prediction accuracy than the environmental factors in predicting SOM; 2) the comprehensive variables of VNIR spectra and the environmental factors can improve about 5.78% and 44.90% relative to soil spectral models and soil environmental models, respectively; 3) the spatial model(GWR) can improve about 3.28% accuracy than MLR and PLSR. Our results suggest that the combination of spectral reflectance and the environmental variables can be used as the suitable auxiliary variables in predicting SOM, and GWR is a promising model for predicting soil properties. 展开更多
关键词 VISIBLE near infrared spectral reflectance environmental factors spatial characteristics partial least SQUARES regression geographically weighted regression
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Spatial Effect of Environmental Regulation on Carbon Emissions 被引量:3
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作者 Wang Min 《Meteorological and Environmental Research》 CAS 2018年第1期57-61,共5页
Based on Chinese provincial panel data from 2003 to 2014,the spatial dependence between the environment regulation and carbon emissions is tested by spatial autocorrelation analysis. Besides,spatial lag model and spat... Based on Chinese provincial panel data from 2003 to 2014,the spatial dependence between the environment regulation and carbon emissions is tested by spatial autocorrelation analysis. Besides,spatial lag model and spatial error model are built to empirically test the marginal effect of environmental regulation on carbon emissions and its spatial effect. The result shows that the influence trajectory of environmental regulation on carbon emissions performances inverted " U" type. It is " green paradox effect" before the inflection point and " reversed transmission reduction effect" after the inflection point. Moreover,the carbon emissions show significant spatial spillover effect. In order to achieve the desired effect of environmental regulation and promote carbon reduction,we should increase the environmental regulation intensity reasonably,select rational environmental regulation policy tools,and sufficiently consider the spatial spillover effect of carbon emissions. 展开更多
关键词 environmental regulation Carbon emissions spatial effect
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Effect of FDI on China's environmental pollution: Evidence based on spatial panel data 被引量:1
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作者 ZHENG Yue-ming 《Ecological Economy》 2018年第2期141-146,共6页
It is clearly stated in the 19th people's congress that we should make the environmental protection as our national policy. Therefore, it is of great importance to study this issue. This article is going to consid... It is clearly stated in the 19th people's congress that we should make the environmental protection as our national policy. Therefore, it is of great importance to study this issue. This article is going to consider 30 provinces of China as the cross-section, and utilize the data sample from 2006 to 2015 of these cross-sections to formulate a Spatial Panel Data Durbin Model to analyze the effect of FDI. By using these data, this article creates a comprehensive environmental pollution index with the help of entropy. The result indicates that the effect of FDI on environment has a non-linear and spatial spillover characteristic. Before reaching the critical value, FDI has a negative effect on environment; however, with the accumulation of FDI, it will create a significant positive effect on the environment. 展开更多
关键词 FDI environmental pollution spatial panel data Durbin model
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Memantine combined with environmental enrichment improves spatial memory and alleviates Alzheimer's disease-like pathology in senescence-accelerated prone-8(SAMP8) mice 被引量:2
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作者 Jingde Dong Mi Zhou +2 位作者 Xiaoqiang Wu Mingyang Du Xiaoshan Wang 《The Journal of Biomedical Research》 CAS 2012年第6期439-447,共9页
Memantine is a N-methyl-D-aspartate (NMDA) receptor antagonist approved for the treatment of moderate to severe Alzheimer's disease (AD). Environmental enrichment (EE) has shown significant beneficial effects on f... Memantine is a N-methyl-D-aspartate (NMDA) receptor antagonist approved for the treatment of moderate to severe Alzheimer's disease (AD). Environmental enrichment (EE) has shown significant beneficial effects on func- tional improvement in AD. In this study, we sought to determine whether combining these two distinct therapies would yield greater benefit than either drug used alone. We investigated the effect of memantine combined with EE on spatial learning and memory and AD-like pathology in a widely used AD model, the senescence-accelerated prone mice (SAMP8). The SAMP8 mice were randomly assigned to enriched housing (EH) or standard housing (SH), where either memantine (20 mg/kg) or saline was given by gastric lavage once daily continuously for eight weeks. Our results showed that, when provided separately, memantine and EE significantly improved spatial learning and memory by shortening escape latencies and increasing the frequency of entrance into the target quadrant. When combined, memantine and EE showed additive effect on learning and memory as evidenced by significant shorter escape latencies and higher frequency of target entrance than either drug alone. Consistent with the behavior results, pathological studies showed that both memantine and EE significantly reduced hippocampal CA1 neurofibrilliary tangles (NFTs) as well as amyloid beta precursor protein (APP) levels. Combining both therapies synergistically lessened NFTs and APP expression compared to either drug alone in SAMP8 mice, indicating that the combination of memantine with EE could offer a novel and efficient therapeutic strategy for the treatment of AD. 展开更多
关键词 MEMANTINE environmental enrichment SAMP8 mouse spatial memory Alzheimer's disease (AD)
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Impact of Holocene environmental change on temporal-spatial distribution of Neolithic sites in Huaihe River Basin, Anhui Province 被引量:5
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作者 HUANG Run ZHU Cheng +1 位作者 GUAN Yong ZHENG Chaogui 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期199-208,共10页
The Huaihe River basin of Anhui is not only a transitional zone of physical geography, but also a convergent area of many cultures in China. It is one of the sensitive ecotones to global changes and the birthplace of ... The Huaihe River basin of Anhui is not only a transitional zone of physical geography, but also a convergent area of many cultures in China. It is one of the sensitive ecotones to global changes and the birthplace of Chinese civilization. Using the field archaeological data and the sporo-pollens and the age data of the drilling cores, we analysed Neolithic cultural development and environmental evolution in the Huaihe River basin of Anhui. According to the combination of some research results in archaeology with environmental evolution research, this paper discusses the relationship between culture and environment in the Huaihe River basin of Anhui. The Neolithic cultural development was strongly impacted by the environmental change. The primitive culture (Shishanzi) was developed in the beginning of the Holocene Megathermal Period with distinct regional feature of the culture. From 6.5 kaBP to 5.5 kaBP, the climate changed warmer and wetter. The frequent occurrence of flood and waterlog due to such a climate regime and high sea level caused the earth's surface environment deteriorated in the Huaihe River basin of Anhui and the interruption of the Neolithic cultural development, hence a lack of archaeological sites. From 5.5 kaBP to 4.0 kaBP, the climate changed from wet to dry, the natural environment was propitious to human survival. Dawenkou Culture and Longshan Culture flourished in this period. The Neolithic cultural development, the number of the sites and their distribution characteristics of the sites in the study area differed apparently from those in Central China and Shandong Province. 展开更多
关键词 HOLOCENE environmental change Neolithic site temporal-spatial distribution Huaihe Riverbasin of Anhui
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Spatial associations between NDVI and environmental factors in the Heihe River Basin 被引量:15
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作者 YUAN Lihua CHEN Xiaoqiang +2 位作者 WANG Xiangyu XIONG Zhe SONG Changqing 《Journal of Geographical Sciences》 SCIE CSCD 2019年第9期1548-1564,共17页
The Heihe River Basin is located in the arid and semi-arid regions of Northwest China.Here,the terrestrial ecosystem is vulnerable,making it necessary to identify the factors that could affect the ecosystem.In this st... The Heihe River Basin is located in the arid and semi-arid regions of Northwest China.Here,the terrestrial ecosystem is vulnerable,making it necessary to identify the factors that could affect the ecosystem.In this study,MODIS-NDVI data with a 250-m resolution were used as a proxy for the terrestrial ecosystem.By combining these with environmental factors,we were able to explore the spatial features of NDVI and identify the factors influencing the NDVI distribution in the Heihe River Basin during the period of 2000–2016.A geographical detector(Geodetector) was employed to examine the spatial heterogeneity of the NDVI and to explore the factors that could potentially influence the NDVI distribution.The results indicate that:(1) the NDVI in the Heihe River Basin appeared high in the southeast while being low in the north,showing spatial heterogeneity with a q-statistic of 0.38.The spatial trend of the vegetation in the three sub-basins generally increased in the growing seasons from 2000 to 2016;(2) The results obtained by the Geodetector(as denoted by the q-statistic as well as the degree of spatial association between the NDVI and environmental factors) showed spatial heterogeneity in the associations between the NDVI and the environmental factors for the overall basin as well as the sub-basins.Precipitation was the dominant factor for the overall basin.In the upper basin,elevation was found to be the dominant factor.The dominant factor in the middle basin was precipitation,closely followed by the soil type.In the lower basin,the dominant factor was soil type with a lower q-statistic of 0.13,and the dominant interaction between the elevation and soil type was nonlinearly enhanced(q-statistic = 0.22). 展开更多
关键词 NDVI environmental factors VEGETATION Geodetector Q-STATISTIC spatial HETEROGENEITY Heihe River BASIN
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Systematized Literature Review on Spatial Analysis of Environmental Risk Factors of Malaria Transmission
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作者 Tiago Canelas Carlos Castillo-Salgado Helena Ribeiro 《Advances in Infectious Diseases》 2016年第2期52-62,共11页
Malaria is still the major parasitic disease in the world, with approximately 438,000 deaths in 2015. Environmental risk factors (ERF) have been widely studied, however, there are discrepancies in the results abo... Malaria is still the major parasitic disease in the world, with approximately 438,000 deaths in 2015. Environmental risk factors (ERF) have been widely studied, however, there are discrepancies in the results about their influence on malaria transmission. Recently, papers have been published about geospatial analysis of ERF of malaria to explain why malaria varies from place to place. Our primary objective was to identify the environmental variables most used in the geospatial analysis of malaria transmission. The secondary objective was to identify the geo-analytic methods and techniques, as well as geo-analytic statistics commonly related to ERF and malaria. We conducted a systematized review of articles published from January 2004 to March 2015, within Web of Science, Pubmed and LILACS databases. Initially 676 articles were found, after inclusion and exclusion criteria, 29 manuscripts were selected. Temperature, land use and land cover, surface moisture and vector breeding site were the most frequent included variables. As for geo-analytic methods, geostatistical models with Bayesian framework were the most applied. Kriging interpolations, Geographical Weighted Regression as well as Kulldorff’s spatial scan were the techniques more widely used. The main objective of many of these studies was to use these methods and techniques to create malaria risk maps. Spatial analysis performed with satellite images and georeferenced data are increasing in relevance due to the use of remote sensing and Geographic Information System. The combination of these new technologies identifies ERF more accurately, and the use of Bayesian geostatistical models allows a wide diffusion of malaria risk maps. It is known that temperature, humidity vegetation and vector breeding site play a critical role in malaria transmission;however, other environmental risk factors have also been identified. Risk maps have a tremendous potential to enhance the effectiveness of malaria-control programs. 展开更多
关键词 MALARIA spatial Analysis environmental Risk Factors Malaria Transmission Malaria Determinants
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Environmental baseline evaluation of lead in shallow groundwater based on statistical and spatial outlier identification
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作者 Linhua Sun 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第3期416-421,共6页
A series of methods have been applied for evaluating the environmental baseline—especially on a regional scale—because of its importance for local environmental management. However, most of the methods have been sta... A series of methods have been applied for evaluating the environmental baseline—especially on a regional scale—because of its importance for local environmental management. However, most of the methods have been statistical in nature, and spatial variability has not been considered simultaneously. In this study, the combined use of statistical and spatial methods has been carried out to analyse lead concentrations in the shallow groundwater in the urban area of Suzhou, northern Anhui Province, China. The environmental baseline of lead in the shallow groundwater has been evaluated to be3.836–8.240 lg/l after removal of either statistical or spatial outliers. The results are similar to those obtained by model-based objective methods, and further demonstrate that the combination method is more reasonable for environmental baseline evaluation. 展开更多
关键词 地下水环境 浅层地下水 和空间 基线 统计 评价 识别 环境管理
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Spatial Distribution of <i>Anopheles sinensis</i>and Its Relationship with Natural Environmental Factors in Wanning County on Hainan Island, China
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作者 Liang Wen Qinghua Li +6 位作者 Minghe Lin Chengyi Li Chenyi Chu Shaowen Weng Wenyi Zhang Yong Wang Shenlong Li 《Journal of Geographic Information System》 2021年第1期36-51,共16页
<i>Anopheles</i> <i>sinensis</i> is widely distributed in Wanning County, it is necessary to understand the spatial distribution characteristics of <i>Anopheles</i> <i>sinensi... <i>Anopheles</i> <i>sinensis</i> is widely distributed in Wanning County, it is necessary to understand the spatial distribution characteristics of <i>Anopheles</i> <i>sinensis</i> in order to maintain the elimination of malaria in Wanning. During May and October 2009, we sampled adult mosquitoes at 36 villages within Wanning County on Hainan island, and collected meteorological and geographical data at each sampling site. We used these data to analyze the spatial distribution of adult <i>Anopheles</i> <i>sinensis</i> mosquitoes, and logistic regression analysis was applied to explore the association of the spatial distribution of <i>Anopheles</i> <i>sinensis</i> with the geographical and meteorological factors. We found that the density of <i>Anopheles</i> <i>sinensis</i> showed a significant positive spatial correlation. From May to October, on the whole, the high-density area was located in the central part of Wanning County. But each month there was a relatively high-density cluster, and their location and range were not exactly the same. From east to west, the density of <i>Anopheles</i> <i>sinensis</i> increased initially and then decreased, but from south to north, there were different trends in the periods of May to August and September to October. Logistic regression analysis showed that the main environmental factors related with the distribution of <i>Anopheles</i> <i>sinensis</i> were land use type, soil type, distance to road, air pressure and relative humidity. These analysis results showed that the distribution of <i>Anopheles</i> <i>sinensis</i> had obvious spatial heterogeneity in Wanning County, which was related with geographical and meteorological factors. The mechanism of these environmental factors on the distribution of <i>Anopheles</i> <i>sinensis</i> needs to be further studied. 展开更多
关键词 Anopheles sinensis spatial Distribution Space-Time Clustering environmental Factors spatial Epidemiological Analysis
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Spatial and environmental effects on plant communities in the Yellow River Delta,Eastern China 被引量:3
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作者 SONG Chuang-ye1, 2, LIU Gao-huan1, LIU Qing-sheng1 1 Institute of Geographic Sciences and Nature Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Graduated School of Chinese Academy of Sciences, Beijing 100039, China 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期117-122,共6页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pat... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods.Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis.The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium.Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation.Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively.Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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Development of a Geographic Information Systems Baseline Spatial Geodatabase Template for Evaluating Potential and Predicted Environmental Impacts for Sustainable Environmental Impact Assessment of Mining in Sierra Leone
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作者 Samuel Mohamed Kamara 《Journal of Geoscience and Environment Protection》 2020年第10期262-284,共23页
Baseline Environmental Impact Assessment (EIA) of mining projects in Sierra Leone creates a challenging environment for data collection and impact prediction. Application of geographic information systems provides sui... Baseline Environmental Impact Assessment (EIA) of mining projects in Sierra Leone creates a challenging environment for data collection and impact prediction. Application of geographic information systems provides suitable spatial analysis data collection methods to reduce the challenges created by mining environments. This research develops a baseline spatial geodatabase template for evaluating potential and predicted environmental impacts assessment of mining projects in Sierra Leone. It is observed that spatial analysis of impacts of mining projects on the environmental attributes, especially air, noise, water, land, and socio-economy in mining areas is largely unexplored in Sierra Leone. The literature review revealed that no complete GIS spatial data geodatabase collection template appears to have been developed to date to provide an integrated sustainable spatial analysis and modelling tool for EIA and environmental management of mining in Sierra Leone. Therefore developing a Geographic Information Systems baseline geodatabase template for the evaluation of potential and predicted environmental impact for sustainable environmental impact assessment of mining in Sierra Leone will: 1) provide support to the data acquisition process of environmental impact assessment, 2) offer a concept for developing analysis methods for environmental management of mining, 3) minimize the undesired environmental impacts of mining, and 4) give an optimal proposal for data collection and analysis of mining industry in attaining sustainable development in Sierra Leone. Due to the limited available data, a conceptual GIS database template has been developed rather than a database case study of a mining site. No site investigation and data collection were undertaken. The geospatial database template was designed using ArcCatalog, ArcGIS 10.7.1. software, through the following steps: exploration of the general data requirement of environmental impact assessment studies of mining, the definition of the general baseline datasets requirement of environmental impact assessment in mining, structuring of the environmental impact assessment baseline spatial geodatabase, creating the geographic geodatabase dictionary, selecting, matching geographic data with geodatabase structure, designing the feature class and attributes, creating the baseline GIS geodatabase template. The GIS spatial geodatabase template has several advantages for environmental impact assessment of mining including avoiding data redundancy, integrating data into a single database, creating uniformity in data collection, easy to find and track data, integrated spatial and non-spatial data, and reducing the volume of data. 展开更多
关键词 GIS environmental Impact Assessment spatial Geodatabase Sustainable environment
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Employment effect of China's environmental regulation: Evidence based on spatial panel data
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作者 ZHENG Yue-ming WANG Ying-dong 《Ecological Economy》 2018年第3期174-179,共6页
This article considers 30 provinces of China as the cross-section subjects, and utilizes the data sample from 2009 to 2015 of these cross-sections to formulate a Spatial Panel Data Durbin Model to analyze the effect o... This article considers 30 provinces of China as the cross-section subjects, and utilizes the data sample from 2009 to 2015 of these cross-sections to formulate a Spatial Panel Data Durbin Model to analyze the effect of environmental regulation on employment. The result indicates that environmental regulation has negative effect on employment with the consideration of spatial spillover effect, and this adverse effect is not significant mathematically. With the enhance of environmental regulation, the negative impact on employment will decrease accordingly, even may eventually promote job growth, which means there may be a non-linear relationship between them. Specifically, the direct effect of environmental regulation on employment indicates that it is beneficial for job growth whereas the indirect effect illustrate that it is detrimental for employment. 展开更多
关键词 environmentAL REGULATION EMPLOYMENT spatial PANEL data Durbin model
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THE TEMPORAL AND SPATIAL PATTERNS OF ENVIRONMENTAL RISK EVENTS IN THE PAST 30 YEARS IN SHENYANG CITY
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作者 Bi Jun Tang Yijian Zhang Shen(Institute of Geography, CAS, Beijing 100101People’s Republic of China)Wang Huadong(Institute of Environmental Sciences, Beijing Normal University, Beijing 100875People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第1期76-86,共11页
The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists si... The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists significant difference of the RFs between periods of 1966-1977 and1978-1991 (t=7.353**, t0.01=2.807). During the past 30 years, there areno significant changes of the spatial patterns of the environmental risk,while the proportions of environmental risk among the districts are extremely different. In Shenyang city, there exists a series of high riskenterprises, and the chemical industry is the one with highest risk. 展开更多
关键词 environmental risk events temporal and spatial patterns risk frequency
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