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Entire Catchment and Buffer Zone Approaches to Modeling Linkage Between River Water Quality and Land Cover——A Case Study of Yamaguchi Prefecture,Japan 被引量:3
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作者 Bahman Jabbarian AMIRI Kaneyuki NAKANE 《Chinese Geographical Science》 SCIE CSCD 2008年第1期85-92,共8页
This study investigated the linkages between river water quality and land use in river catchments in Yama- guchi Prefecture, the western Japan, in order to examine the effect of land use changes of both entire catchme... This study investigated the linkages between river water quality and land use in river catchments in Yama- guchi Prefecture, the western Japan, in order to examine the effect of land use changes of both entire catchment and buffer zone on river water quality. Dissolved Oxygen (DO), pH, Biological Oxygen Demand (BOD), Suspended Solids (SS), Escherichia coli, Total Nitrogen (TN) and Total Phosphorus (TP) were considered as river water quality indica- tors. Satellite images were applied to generating the land use map. Multiple regression model was applied to linking the changes in the river water quality with the land uses in both entire catchment area and buffer zone. The results in- dicate that the integrative application of land use data from the entire catchment and the buffer zone could give rise to more robust model to predict the concentrations of Suspended Solids (r2=0.88) and Total Nitrogen (r2=0.90), rather than models which separately considered land use data in catchment and buffer zone. 展开更多
关键词 land use water quality buffer zone entire catchment Yamaguchi Prefecture JAPAN
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Research on Two Types of Buffer Zone Impact on Surrounding Office Space Environment in Winter in Cold Climate Zone—a Fieldwork in Architectural Design Institute Building of Tsinghua University,Beijing 被引量:1
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作者 Ye-Hao Song Jun-Jie Li +2 位作者 Ning Zhu Jia-Liang Wang Shi-Meng Hao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第5期33-39,共7页
Building buffer zone space is not only one of essential approaches for better mental quality of interior building space, but also an important factor that may influence interior thermal comfort and energy consumption.... Building buffer zone space is not only one of essential approaches for better mental quality of interior building space, but also an important factor that may influence interior thermal comfort and energy consumption. This study aims to analyze regulative advantages of buffer zone to the surrounding functional spaces. Based on a fieldwork test in a typical office building in cold climate zone in Beijing,China,the monitor data show interior physical performance in the Winter. The research selects two types of different buffer zones in the same building. One is a south-faced greenhouse which has large dimension with plenty of vegetation,and the other is a simple atrium in the middle of five floor building with mount of skylights. The factors and their influence to surrounding functional spaces and the whole building are found out from the comparisons of collected data by floor to floor monitor test on both buffer zones at the same time. The comparisons of two types of buffer zones conclude that the greenhouse is more effective to air quality regulation but not so clearly wellperformed to thermal buffering as expected due to the dominate active central heating in the Winter. This fieldwork test results for building performance can be helpful for both architects and engineers in the early phase of sustainable design. 展开更多
关键词 public building buffer zone building performance fieldwork test space effect
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Comparison of structural diversity of tree-crop associations in Peripheral and Buffer zones of Gachabari Sal forest area,Bangladesh
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作者 M.M. Rahman H. Vacik +2 位作者 F. Begum A. Nishad K.K. Islam 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期23-26,共4页
The structural diversity of different tree-crop associations were studied at Gachabari Sal forest area of Madhupur Garh on Buffer and Peripheral Zone during 2006. The total density, basal area of trees in the Buffer a... The structural diversity of different tree-crop associations were studied at Gachabari Sal forest area of Madhupur Garh on Buffer and Peripheral Zone during 2006. The total density, basal area of trees in the Buffer and Peripheral Zone were 155.5 trees·hm^(-2), 795.4 trees·hm^(-2) and 3.9 m2·hm-2, 5.8 m^2·hm^(-2), respectively. No regeneration and natural trees were found in Peripheral Zone and the Zone is totally occupied by exotic species where the Buffer Zone comprised of both natural and exotic trees. The Peripheral Zone belonged to younger and smaller trees whereas the Buffer Zone belonged to mixture of smaller, taller, younger and mature trees simultaneously. For the practicing of different agroforestry systems both Zones have lost their original characters of Sal forest. 展开更多
关键词 Structural diversity Tree-crop associations Sal Peripheral and buffer zone.
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Comparison of structural diversity of tree-crop associations in Periph- eral and Buffer zones of Gachabari Sal forest area, Bangladesh
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作者 M.M. Rahman F. Begum +2 位作者 A. Nishat K.K. Islam H. Vacik 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期165-165,共1页
The original version of this article unfortunately contained three mistakes. (1) The spelling of the [A. Nishad'] name was incorrect. The corrected spelling is given below.
关键词 Structural diversity Tree-crop associations Sal Peripheral and buffer zone.
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Assessing Forest Cover Distribution, Species Diversity, and Richness of the Buffer Zone for Strategic Forest Management Planning for Nimule National Park, South Sudan
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作者 Joseph Mayindo Mayele Augustine Lokule Bongo 《Open Journal of Ecology》 2023年第11期836-864,共29页
Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected ... Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected areas reduce the loss and degradation of natural habitats to various wild species of plants. This study examined the forest resources in five subzones by conducting tree/shrub species inventory to be able to develop an effective forest management plan for the Buffer Zone Forest Reserve for the sustainable conservation of flora and fauna of Nimule National Park. This is with the view to identify the main tree and shrub species;assess the composition, distribution, and abundance of various tree/shrub species;to determine the species diversity as well as the richness of these areas in terms of growth and performance where DBH and heights of trees/shrubs in the circular sample plots were measured. The results revealed the overall mean DBH and H of 13.83 cm and 6.61 m respectively. The highest number of trees was obtained in subzone B followed by D, while the least were found in subzone A. The overall mean tree/shrub density was 0.83 tons/ha. The mean total basal area and volume per hectare were 3252.74 m<sup>2</sup>/ha and 46,540.82 m<sup>3</sup>/ha respectively. The overall species abundance and distribution indicate Combretum spp, Cedrella spp., Grewia mollis, Acacia Sieberiana, Ziziphus abysinica, and Acacia seyal were the most dominant species, with over 12 species richness at the deposition side of the River Nile, 13 species at the western side of the Nile, the Administration site shows only 7 species, the lowland of Mt. Gordon show over 14 different species, whereas over 10 species were found on the top of Mt. Gordon. The overall mean diversity indices and evenness of H’, D, and E depicted 2.507, 0.871, and 0.840 respectively. These results yielded are relatively moderate. Therefore, conservation efforts are very necessary to improve and maintain the quality of vegetation cover. 展开更多
关键词 Species Diversity Species Abundance Species Richness buffer zone Nimule National Park South Sudan
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Construction of a Linear Engineering Visual Landscape Interference Model for the Buffer Zone of the Libo Heritage Site Based on the AHP-Fuzzy Comprehensive Evaluation Method:A Case Study of the Guiyang-Nanning High-Speed Railway
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作者 WEI Wei MA Zhenrui XIAO Shizhen 《Journal of Landscape Research》 2025年第5期12-19,共8页
The buffer zone of a World Natural Heritage Site constitutes a critical element of the heritage site protection system.It not only functions as an ecological security barrier,but also significantly influences the visu... The buffer zone of a World Natural Heritage Site constitutes a critical element of the heritage site protection system.It not only functions as an ecological security barrier,but also significantly influences the visual integrity and aesthetic value of the core area’s landscape.Given the rapid development of transportation infrastructure,particularly the growing number of high-speed railways traversing ecologically sensitive regions,the scientific assessment of their impact on the landscape environment of heritage sites has emerged as a pivotal concern in heritage conservation and regional development.This study focused on the section of the Guiyang-Nanning High-Speed Railway that traverses the buffer zone of the Libo World Natural Heritage Site in Guizhou Province.Beginning with five primary indicators,including natural landscape and aesthetic value,geological geomorphology and Earth history value,biodiversity value,integrity and protection management,and impact on ecological environment,a visual landscape impact assessment system for high-speed railways was developed based on the analytic hierarchy process(AHP)and the fuzzy comprehensive evaluation method(FCE).Through expert scoring,hierarchical weight calculation,and fuzzy membership degree analysis,a comprehensive assessment was conducted on the landscape ecological quality,visual coordination,and aesthetic perception within the buffer zone following the construction of high-speed railways.The findings indicate that the construction of the Guiyang-Nanning High-Speed Railway generally harmonizes well with the landscape environment of the heritage site.The level of visual disturbance remains within an acceptable range and has not significantly damaged the overall aesthetic value or authenticity of the heritage site.Although the integrity of the landscape in certain local areas has experienced a slight decline due to the exposure of bridge and slope structures,the adverse effects have been effectively mitigated through engineering interventions such as vegetation restoration and color coordination.This study innovatively integrates the AHP with fuzzy mathematics methods to achieve a comprehensive evaluation that combines both qualitative and quantitative approaches.This integration provides a scientifically grounded analytical path and a practical technical framework for assessing the visual impact of linear infrastructure projects,such as high-speed railways,within the buffer zones of World Heritage Sites.The findings offer valuable insights for the protection of landscapes and the sustainable development of infrastructure in heritage sites. 展开更多
关键词 Heritage site buffer zone Analytic hierarchy process(AHP) Fuzzy comprehensive evaluation method(FCE)
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Assessment of buffer zone for aquatic organisms in pesticide application 被引量:2
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作者 Nigar Yarpuz-Bozdogan 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2016年第5期227-234,共8页
In pesticide applications,the buffer zone helps to protect water sources against pesticide contamination.In 2014,in the Adana province,the percentage of herbicides used was approximately 12%in corn,sunflower,soybean a... In pesticide applications,the buffer zone helps to protect water sources against pesticide contamination.In 2014,in the Adana province,the percentage of herbicides used was approximately 12%in corn,sunflower,soybean and cotton.To control the weeds,fifteen active ingredients(a.i.)were used in these crops in 2014.These a.i.were acetochlor,aclonifen,benfluralin,bromoxynil,clethodim,dicamba,fluazifop-p-butyl,foramsulfuron,linuron,mesotrione,nicosulfuron,oxyfluorfen,prometryn,trifluralin and tritosulfuron.The aim of this study was to assess the risk of these herbicides on aquatic organisms and estimate buffer zone distances for the above agricultural crops in herbicide application.Risk index(RI)values were calculated according to German Drift Model(GDM)and Dutch Drift Model(DDM).Consequently,buffer zone needs for herbicide application of five a.i.,namely acetochlor,benfluralin,linuron,prometryn,and trifluralin,were determined in this study.Results showed that acetochlor a.i.has the highest risk to aquatic organisms and needs a buffer zone distance of more than 57 meters in sunflower cultivation.It was assessed that buffer zone distances should be more than 1.32 m for linuron in soybean,3.5 m for benfluralin in sunflower,4.13 m for prometryn(1.5 kg a.i./hm^(2))in sunflower and 4.19 m for trifluralin in cotton and soybean,and 5.54 m for prometryn(2.0kg a.i./hm^(2))in cotton.There was no need for a buffer zone in corn. 展开更多
关键词 buffer zone PESTICIDE HERBICIDE risk index COTTON SUNFLOWER CORN SOYBEAN
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Spatial Variability of Microclimate Characteristics in Transition Zone of the Forest: A Case Study of Slătioara Secular Forest
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作者 Marius Dan Șandru 《Open Journal of Forestry》 2024年第4期369-396,共28页
Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. W... Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. With this study, we investigate to what extent microclimatic variables (air temperature—T_air, air humidity—H_air, soil temperature—T_soil, soil humidity—H_soil wind intensity (WIND) and photosynthetically active radiation intensity (PAR)) are correlated with the distance from the edge to the forest interior and the habitat type (forest interior, inner and outer edge and meadow) in the Slătioara Secular Forest Reserve. In order to measure these microenvironment variables we used the strip transect method, positioned perpendicular to the forest edge. Differences in the microenvironment variables considered in the analysis between the four habitat types were assessed using one-way ANOVA followed by Tukey-test post-hoc. To assess differences along transects, each of the six measurements went through a one-way ANOVA against distance to edge, followed by a Levene’s test for variances and finally a Tukey-test post-hoc. The results indicate that the values of microclimatic variables were significantly different in relation to the gradient of distance from the edge and to the habitat type (interior-exterior forest) and that edge habitats are significantly more susceptible to lower humidity, high winds, lower light and higher air temperatures than forest interior habitats. The ecological study of the edge areas in this reserve provides the basis for future research on forest dynamics and can guide conservation efforts to maintain the diversity and endemism of species in the Slătioara Secular Forest. 展开更多
关键词 Component Forest Microclimate Edge Effects Edge-Interior Relationships Forest buffer zone Edge Influence Microclimatic Influences
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汶水河流域滨水缓冲带安全宽度规划研究
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作者 秦志强 邹晔 +3 位作者 郭人泰 郭刘鹏 王超 薛良方 《环境污染与防治》 北大核心 2025年第4期35-41,47,I0002,I0003,共10页
基于SWAT模型建立了汶水河流域非点源污染模型,估算了流域内污染物负荷,利用经验公式预测了径流通过滨水缓冲带边界时的污染物浓度,通过相关性分析识别了决定该河段滨水缓冲带最小安全宽度的关键变量。结果表明:1)SWAT模型适合进行径流... 基于SWAT模型建立了汶水河流域非点源污染模型,估算了流域内污染物负荷,利用经验公式预测了径流通过滨水缓冲带边界时的污染物浓度,通过相关性分析识别了决定该河段滨水缓冲带最小安全宽度的关键变量。结果表明:1)SWAT模型适合进行径流、总氮(TN)和总磷(TP)模拟。2)地表径流中TN和TP负荷由上游至下游呈增加趋势。3)滨水缓冲带安全宽度受到连接度、坡度、耕地面积和人口密度的影响。上、中、下游滨水缓冲带应各自维持77.90、33.37、60.65 m的安全宽度。 展开更多
关键词 非点源污染 SWAT模型 滨水缓冲带 安全宽度 径流
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长潭水库小流域地表水质对景观格局的响应特征及尺度效应研究 被引量:1
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作者 邹奕巧 赵钿钿 +5 位作者 马桂莲 吴江 林雪锋 盖旭 张涵丹 陈光才 《长江流域资源与环境》 北大核心 2025年第5期1062-1072,共11页
水质对土地利用和景观格局的变化较为敏感,为探究不同尺度下的景观格局与水质之间的关系,研究以长潭水库为例,基于2021年水质监测数据,对各入库支流以100m为间隔进行缓冲区划分,计算50~650 m7个带状缓冲区的景观特征,并采用Pearman相关... 水质对土地利用和景观格局的变化较为敏感,为探究不同尺度下的景观格局与水质之间的关系,研究以长潭水库为例,基于2021年水质监测数据,对各入库支流以100m为间隔进行缓冲区划分,计算50~650 m7个带状缓冲区的景观特征,并采用Pearman相关分析和冗余分析对水质与景观格局的响应关系进行研究。结果表明:(1)库区小流域以林地为主,耕地和水体次之;林地面积占比随着缓冲半径的增加而增加,耕地和建设用地相反。(2)耕地、建设用地、蔓延度指数(CONTAG)和香农多样性指数(SHDI)与水质指标呈正相关关系,其中耕地是库区水质污染的重要来源;(3)景观格局对水质的解释率在250m半径最高。在该范围内,景观破碎化程度高,人类活动最为强烈。建议在各支流250 m范围内严格控制耕地的耕种模式,通过建设河岸缓冲带、水库前置库等方法来提高对污染物的拦截能力,从而保护库区小流域的水环境安全。 展开更多
关键词 景观格局 缓冲区 水质特征 冗余分析
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阿尔泰山路网格局对自然保护地景观生态的影响 被引量:1
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作者 侯金超 韩芳 +1 位作者 王伯礼 胥睿 《生态学杂志》 北大核心 2025年第7期2365-2376,共12页
道路网是导致区域土地利用和景观格局变化加剧的关键因素之一,如何衡量路网修建与生态保护之间的关系是目前的一个热点问题。本文以阿尔泰山自然保护地为研究区域,利用2020年不同等级路网数据,选取2000年、2010年和2020年的土地利用数据... 道路网是导致区域土地利用和景观格局变化加剧的关键因素之一,如何衡量路网修建与生态保护之间的关系是目前的一个热点问题。本文以阿尔泰山自然保护地为研究区域,利用2020年不同等级路网数据,选取2000年、2010年和2020年的土地利用数据,采用缓冲区分析、土地动态变化、景观格局分析方法,探讨路网两侧不同距离范围内土地利用和景观格局之间的关系。结果表明:(1)2000—2020年,各等级道路都在不同程度上加剧了土地利用类型变化,尤其是低等级道路两侧土地利用类型改变得更加明显;(2)2000—2020年各等级道路中林地和草地是其他土地类型的主要来源,省道和国道中,林地和草地对水域和未利用地贡献率最高(>6.84%),县道、乡道和等外道路中,林地和草地对居民用地和未利用地贡献率最高(>6.15%);(3)2000—2020年各等级道路缓冲区的斑块面积和斑块形状指数都有了一定的增加,低等级道路缓冲区斑块面积增长速度高于高等级道路,且道路斑块形状也更为复杂,景观破碎化更显著。综上,低等级道路两侧土地利用类型变化明显,林地和草地受道路建设的影响较大。今后路网建设不仅需要提前评估对沿线生态环境的影响,减少路网建设前后对阿尔泰山自然保护地生态系统带来的负面影响,还需要建立长期监督机制,确保对生态环境变化能及时管理和控制。 展开更多
关键词 土地利用 缓冲区 景观格局 阿尔泰山自然保护地
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不同内外部因素对生态缓冲带氮磷污染净化效果的影响
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作者 陈磊 陈应健 +4 位作者 夏小林 张靖雨 高畅 郭伟玲 邹志科 《水土保持通报》 北大核心 2025年第5期1-10,共10页
[目的]探究生态缓冲带(EBZs)在不同内外部因素综合作用下对径流和渗流水体中氮、磷污染物的净化效果,为农业面源污染治理提供优化设计依据。[方法]采用正交试验,选取植被配置方式、坡度两个内部因素以及入流污染物浓度、入流流量两个外... [目的]探究生态缓冲带(EBZs)在不同内外部因素综合作用下对径流和渗流水体中氮、磷污染物的净化效果,为农业面源污染治理提供优化设计依据。[方法]采用正交试验,选取植被配置方式、坡度两个内部因素以及入流污染物浓度、入流流量两个外部因素,探究生态缓冲带在不同内外部因素综合作用下对径流和渗流水体中氮、磷污染物的净化效果,并利用极差分析法分析不同内外部因素对生态缓冲带截污能力的影响程度。[结果]生态缓冲带对地下渗流中TN,TP的削减效果(21.31%和29.80%)明显优于对地表径流中TN,TP的削减效果(16.91%和23.04%);复合植被配置生态缓冲带截污效果优于纯草本配置,其中灌木+草本截污效果最佳,对地表径流和地下渗流中TN和TP的平均削减率分别为20.16%,27.24%以及24.54%,33.89%;生态缓冲带不同内外部因素对不同类型污染物的具体影响程度存在显著差异,总体上,由大到小均按照以下顺序排列:植被配置类型>入流污染物浓度>坡度>入流流量。[结论]对生态缓冲带截污能力影响最大的因素是植被配置类型,但随着缓冲带坡度、入流流量和入流污染物浓度增大,不同植被配置缓冲带对污染物的削减率总体均呈下降趋势。 展开更多
关键词 生态缓冲带(EBZs) 影响因素 面源污染 径流 渗流 削减率
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太中银铁路对沿线土地利用及生态风险影响
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作者 雷泽鑫 李丽君 +1 位作者 韦妍柔 赵旭强 《铁道工程学报》 北大核心 2025年第3期90-95,共6页
研究目的:黄土高原地区铁路建设在推动经济发展的同时,对区域土地利用及脆弱生态造成显著影响。为探讨铁路建设对黄土高原土地利用的影响,本文通过太中银铁路建成前后景观指数变化确定铁路建设沿线的关键干扰范围,并基于此对干扰区内土... 研究目的:黄土高原地区铁路建设在推动经济发展的同时,对区域土地利用及脆弱生态造成显著影响。为探讨铁路建设对黄土高原土地利用的影响,本文通过太中银铁路建成前后景观指数变化确定铁路建设沿线的关键干扰范围,并基于此对干扰区内土地利用类型和生态风险动态变化进行归纳。研究结论:(1)铁路沿线3km内景观格局显著变化,特别是铁路建设期间,斑块形态趋于简单集中,景观破碎化加剧、多样性提升;(2)铁路显著干扰范围内土地利用变化强度大、速度快、变化程度高,区域开发强度在铁路建设及运营阶段逐步加大;(3)显著干扰范围内,生态风险指数(ERI)在铁路建设期显著增加、高风险区域快速扩展;铁路运营期间生态风险趋于稳定,但部分高风险区域仍然持续存在,反映出铁路建设与运营对生态环境的长期影响;(4)本研究结果可为黄土高原地区铁路规划与建设中的生态保护提供科学依据,强调发展与保护之间寻求平衡的重要性。 展开更多
关键词 铁路建设 黄土高原 缓冲区 土地利用/覆被变化 生态风险指数
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Spatial Distribution and Fluorescence Properties of Soil Dissolved Organic Carbon Across a Riparian Buffer Wetland in Chongming Island,China 被引量:13
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作者 WANG Yu-Lai YANG Chang-Ming +1 位作者 ZOU Li-Min CUI Heng-Zhao 《Pedosphere》 SCIE CAS CSCD 2015年第2期220-229,共10页
The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few stud... The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few studies have investigated the sources and properties of DOC in riparian zones.A total of 34 soil samples were collected across four riparian buffer zones(Zones A-D) on Chongming Island,China.The vertical distributions of soil organic carbon(SOC) and DOC,fluorescence excitation-emission matrix(EEM) spectra of DOC and the optical indices,including fluorescence index(FI),index of recent autochthonous contribution(BIX),and humification index(HIX),were measured across the riparian environment to investigate the sources and fluorescence properties of DOC.The results showed that SOC stored in the surface soil(0-30 cm) accounted for 40%of the total soil profile SOC.The DOC accumulated in Zones A-C,which accounted for 5%of the SOC.The fluorescence EEM spectra of DOC showed that DOC contained humic-like and protein-like substances,which were mainly derived from recent plant debris by microbes.A large amount of humic-like substances were sorbed to minerals in the surface soil(0-30 cm).In addition,the riparian topography and soil physico-chemical properties(pH,EC and moisture) dictated the transformation and transport of DOC.The results suggested that EEMs could reveal the source of DOC in riparian soil systems,and that optical indices were complementary tools that revealed the characteristics of soil DOC and provided supplemental evidence about DOC sources. 展开更多
关键词 excitation-emission matrix(EEM) riparian buffer zone fluorescence index(FI) humification index(HIX) optical indices
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植被缓冲带固土护坡效应研究——以涪江流域潼南段为例 被引量:2
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作者 王鑫皓 黄盛 +4 位作者 李通 祁子寒 胡月 李克文 闫相君 《中国水土保持科学》 北大核心 2025年第2期199-209,共11页
植被缓冲带是河岸生态系统的重要组成部分,在固土护坡方面具有重要的作用。本研究以涪江流域潼南段河岸植被缓冲带为研究对象,通过样方调查、室内试验和野外试验等,确定沿岸植被缓冲带的物种组成和优势种,根系的力学和形态特征以及固土... 植被缓冲带是河岸生态系统的重要组成部分,在固土护坡方面具有重要的作用。本研究以涪江流域潼南段河岸植被缓冲带为研究对象,通过样方调查、室内试验和野外试验等,确定沿岸植被缓冲带的物种组成和优势种,根系的力学和形态特征以及固土护坡效果。主要结果:1)河流沿岸缓冲带共有植物2门3纲16目19科30属35种,主要为被子植物和蕨类植物2大类,优势物种为狗牙根、芦苇、草木樨、狗尾草、小蓬草。2)当根系直径<0.2 mm时,狗牙根根系的抗拉强度最高;当根系直径>0.2 mm时,草木樨根系的抗拉强度最高。3)植物根系的存在具有明显抗冲效果,最大冲刷深度时间延迟1~4 min,冲刷深度降低938 mm,侵蚀量减少20.17%~58.90%,狗牙根的抗冲刷效果明显好于狗尾草;根系的存在能够显著提升土体的抗剪强度,使剪切峰值延缓0.26~4.80 cm,剪切峰值提升4.76~11.37 kPa,能量消耗增加23.76%~46.11%。抗剪切效果最好的是芦苇,其次是小蓬草,最后是草木樨。综上,为了兼顾植物根系的抗冲刷效果和抗剪切效果,推荐狗牙根和芦苇进行浅根–深根搭配种植来提升河岸的水土保持能力。 展开更多
关键词 植被缓冲带 水土保持 抗冲性 抗剪强度
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顾及缓冲区范围与负样本优化的随机森林地质灾害易发性评价 被引量:1
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作者 刘少泽 崔美娟 +1 位作者 付晓祎 唐宗源 《科学技术与工程》 北大核心 2025年第15期6220-6229,共10页
为了提升地质灾害易发性评价的精度,以浙江省杭州市富阳区为研究区,提出了考虑缓冲区优化策略的随机森林地质灾害易发性评价方法。首先,选取归一化植被指数、距道路距离、距断层距离、汛期降雨量、坡度、坡向、起伏度、距水系距离和岩性... 为了提升地质灾害易发性评价的精度,以浙江省杭州市富阳区为研究区,提出了考虑缓冲区优化策略的随机森林地质灾害易发性评价方法。首先,选取归一化植被指数、距道路距离、距断层距离、汛期降雨量、坡度、坡向、起伏度、距水系距离和岩性共9个评价因子,通过多重共线性分析确保因子的独立性。其次,构建0.5、1、1.5、2 km 4种缓冲区范围,以随机采样方法生成负样本点,避免正负样本交叉污染,提高样本代表性和模型的区分能力,并增设一组无缓冲区的随机采样点作为参照。接着,采用随机森林算法对地质灾害易发性模型进行训练和测试,结果表明缓冲区优化策略能够显著提升模型预测精度,且缓冲区的设定存在最优边界。其中,1 km缓冲区对应的模型AUC(area under curve)值最高为0.815,表明该缓冲区设定下采集的负样本能够更加准确地区分地质灾害特征。最后,基于最优缓冲区与随机森林算法(random forest,RF)模型的易发性评价结果,高易发区主要集中在西北部和东南部的山区地带,且频率比随着易发性等级升高而不断增大,验证了这一方法的科学性,可为富阳区的地灾防治工作提供依据。 展开更多
关键词 地质灾害 缓冲区 随机森林 易发性评价 地理信息
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昆石高速公路修建对周边景观格局的影响 被引量:1
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作者 文元勇 段文红 +4 位作者 仝跃 刘娇 杨子江 田涛 钟荣华 《云南大学学报(自然科学版)》 北大核心 2025年第3期485-493,共9页
为了揭示高速公路建设区的景观格局演变规律,以昆明至石林风景区公路(昆石高速)为例,通过ArcGIS 10.3软件和Fragstats 4.2软件,建立不同范围缓冲区,结合景观格局指数分析昆石高速公路2000—2020年间的景观格局演变.结果表明:高速公路建... 为了揭示高速公路建设区的景观格局演变规律,以昆明至石林风景区公路(昆石高速)为例,通过ArcGIS 10.3软件和Fragstats 4.2软件,建立不同范围缓冲区,结合景观格局指数分析昆石高速公路2000—2020年间的景观格局演变.结果表明:高速公路建设导致了景观格局整体向破碎化发展,道路两侧1 km缓冲区内自然景观斑块数、斑块密度、景观分离度增加;不同景观类型对高速公路修建的响应范围存在差异,总体上看,昆石高速公路修建的景观响应主要范围为公路沿线两侧宽度200~500 m;合理的生态保护和水土保持措施,可以有效地缓解高速公路沿线景观破碎化,扰损的景观生态经过一定恢复期限能够逐步恢复. 展开更多
关键词 景观格局 高速公路建设 缓冲区 昆石高速
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淮南煤矿区典型地表水水质特征及其土地利用类型结构响应
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作者 朱芬芬 李湘凌 +3 位作者 赵燕 袁竹青 穆璐璐 蔡诗颖 《环境科学学报》 北大核心 2025年第7期168-180,共13页
为探究高潜水位采煤矿区地表水质特征及其对土地利用类型结构的响应,分别采集淮南市北部西淝河、泥河地表水24组和典型塌陷坑塘的地表水19组.分析地表水的总氮(TN)、总磷(TP)、高锰酸盐指数(COD_(Mn))、氨氮(NH_(3)-N)、溶解氧(DO)、pH... 为探究高潜水位采煤矿区地表水质特征及其对土地利用类型结构的响应,分别采集淮南市北部西淝河、泥河地表水24组和典型塌陷坑塘的地表水19组.分析地表水的总氮(TN)、总磷(TP)、高锰酸盐指数(COD_(Mn))、氨氮(NH_(3)-N)、溶解氧(DO)、pH、Cu、Zn、Pb和As含量,采用“一票否决制”评价地表水水质;运用ArcGIS提取50~1000 m缓冲尺度下的土地利用类型,采用相关性、冗余分析法及岭回归分析法研究了河流及塌陷坑塘地表水水质与土地利用类型的关系.结果表明:①研究区河流地表水为Ⅲ类~劣Ⅴ类,塌陷坑塘地表水水质除个别点位外均为劣Ⅴ类,TN、TP和COD_(Mn)是地表水中主要污染物,其中TN的污染贡献最大;河流地表水和塌陷坑塘地表水水质分别受到塌陷和坑塘养殖及煤矸石填埋影响大.②不同缓冲尺度下的土地利用类型结构对地表水解释率低,但河流地表水和塌陷坑塘地表水分别在塌陷影响和坑塘利用方式的约束条件下,河流地表水及坑塘地表水水质对土地利用类型结构的响应水平明显提高;河流地表水具有更高的响应水平,土地利用类型结构对河流地表水水质变化最大解释率及模型可决系数分别为69.2%和0.88.③在300 m最佳缓冲尺度下,塌陷对河流地表水TN、TP和COD_(Mn)影响(显著正向)最大,其次为耕地(显著负向).因此,在高潜水位采煤矿区引入塌陷影响约束条件可以有效提高河流地表水的水质对土地利用类型结构的响应水平,研究结果为煤矿区土地利用的管理提供了重要的依据,也为改善矿区河流水质提供了参考. 展开更多
关键词 煤矿区 塌陷 地表水水质 土地利用类型结构 缓冲区分析
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永定河门头沟段生态岸线现状特征分析
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作者 兰怡杭 汪文龙 张振明 《湿地科学》 北大核心 2025年第2期252-261,共10页
门头沟区位于北京市西南部,境内有永定河流经。永定河作为北京市重要的水源地之一,其生态岸线对永定河的生物多样性、水质和可持续发展有着重大影响。以北京市永定河门头沟段生态岸线为研究对象,通过实地考察、实验室分析等方法,开展生... 门头沟区位于北京市西南部,境内有永定河流经。永定河作为北京市重要的水源地之一,其生态岸线对永定河的生物多样性、水质和可持续发展有着重大影响。以北京市永定河门头沟段生态岸线为研究对象,通过实地考察、实验室分析等方法,开展生态岸线现状调查,提出修复建议,并分析水质状况和底栖动物多样性。研究结果表明,从物理特征可以看出永定河岸线存在硬质化及景观单调等问题;水质状况大部分可以达到地表水Ⅲ类水域标准,永定河岸线水体氨氮质量浓度在0.048~1.070 mg/L之间,总氮质量浓度在0.439~1.850 mg/L之间,总磷质量浓度在0.042~0.221 mg/L之间,pH在7.40~8.58之间,溶解氧质量浓度在7.18~8.26 mg/L之间,高锰酸盐指数在1.30~4.07 mg/L之间;底栖动物Margalef丰富度指数在0.88~2.63之间,底栖动物Shannon-Wiener多样性指数在0.5~1.7之间。根据当前岸线物理特征、水质状况、底栖动物多样性综合分析,筛选出物理特征状况较差、水质较差、底栖动物多样性水平较低的岸线采样点,并根据各种不足分别提出了护岸工程、河岸缓冲带与小微丁坝3种修复建议措施。 展开更多
关键词 永定河门头沟段 生态岸线 护岸工程 河岸缓冲带 小微丁坝
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基于软隔离解决DSS 900 MHz边界同频干扰的方法
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作者 周杰华 陈翔 许国平 《邮电设计技术》 2025年第8期47-50,共4页
随着900 MHz频段的低频重耕用于5G建设,当前900 MHz频率同时承载了3G/4G/5G 3张不同制式的网络,因此在不同网络的交界区因频率重叠易引起同频干扰。提出一种软隔离方案解决同频干扰问题,通过配置切换参数,与L1.8 GHz/2.1 GHz/900 MHz、N... 随着900 MHz频段的低频重耕用于5G建设,当前900 MHz频率同时承载了3G/4G/5G 3张不同制式的网络,因此在不同网络的交界区因频率重叠易引起同频干扰。提出一种软隔离方案解决同频干扰问题,通过配置切换参数,与L1.8 GHz/2.1 GHz/900 MHz、NR2.1 GHz/3.5 GHz/900 MHz进行互操作,提升DSS 900 MHz切换准入门限,降低DSS 900 MHz切换出门限,使用户在隔离区中主要占用4G、5G中高频网络,从而降低隔离区内900 MHz网络同频干扰。此方案能有效降低维优成本,避免在隔离区内因拆站及清频,带来的网络性能感知劣化。 展开更多
关键词 软隔离 互操作 隔离区 同频干扰 频率重叠
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