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1.
Serious soil erosion is one of the major issues threatening sustainable land use in semiarid areas, especially in the Loess Plateau of China. Understanding the effects of land use on soil and water loss is important for sustainable land use strategy. Two sub-catchments: catchment A (CA) and catchment B (CB) with distinct land uses were selected to measure soil moisture, runoff and soil nutrient loss in Da Nangou catchment of the Loess Plateau of China. The effects of land use patterns on runoff and nutrient losses were analyzed based on soil moisture pattern by kriging and soil nutrients using multiple regression model. The results indicated that there were significant differences in runoff yield and soil nutrient losses between the two sub-catchments. With similar land uses, the CA produced an average sediment yield of 49 kg ha-1 and 22.27 kg ha-1 during two storm events.Meanwhile, there was almost no runoff in the CB with dissimilar land uses during the same events.Buffer zones should be established to re-absorb runoff and to trap sediments in catchment with similar land use structure such as the CA. Moreover, land use management strategy aiming to increase the infiltration threshold of hydrological response units could decrease the frequency of runoff occurrence on a slope and catchment scale. 相似文献
2.
Serious soil erosion is one of the major issues threatening sustainable land use in semiarid areas, especially in the Loess Plateau of China. Understanding the effects of land use on soil and water loss is important for sustainable land use strategy. Two sub-catchments: catchment A (CA) and catchment B (CB) with distinct land uses were selected to measure soil moisture, runoff and soil nutrient loss in Da Nangou catchment of the Loess Plateau of China. The effects of land use patterns on runoff and nutrient losses were analyzed based on soil moisture pattern by kriging and soil nutrients using multiple regression model. The results indicated that there were significant differences in runoff yield and soil nutrient losses between the two sub-catchments. With similar land uses, the CA produced an average sediment yield of 49 kg ha-1 and 22.27 kg ha-1 during two storm events. Meanwhile, there was almost no runoff in the CB with dissimilar land uses during the same events. Buffer zones should be established to re-absorb runoff and to trap sediments in catchment with similar land use structure such as the CA. Moreover, land use management strategy aiming to increase the infiltration threshold of hydrological response units could decrease the frequency of runoff occurrence on a slope and catchment scale. 相似文献
3.
北京市郊区游憩空间分布规律 总被引：10，自引：2，他引：8
郊区是城市发展的腹地,郊区游憩空间不仅能够满足都市居民出游的需求,而且对维护城市生态安全具有重要意义。本文选取北京作为案例地,对郊区的游憩空间布局规律进行研究。在前期研究的基础上,结合网络、文献、调研收集数据,将游憩空间按照功能划分为3类：公共游憩空间、商业游憩空间与附属游憩空间;将不同功能、不同经营主体与不同土地利用的游憩空间组织起来,从而建立北京郊区游憩空间采样数据库,采用GIS空间分析的技术手段得出结论。研究发现,北京郊区各类游憩空间布局具有空间分异规律。公共游憩空间中风景名胜区分布在远郊的山区;城市公园与城市形态相关;郊野公园属于政策导向型的游憩空间,在一定程度上缓解了资源本底条件造成的游憩空间不均匀分布。商业游憩空间呈现产品的空间分异,并与交通、水系条件密切相关;乡村游憩设施依托于大型景区,并与农业传统相关。北京郊区的游憩空间已经初步具备网络结构并向纵深发展,出现了产业集中区。最后指出北京游憩空间布局中存在的不合理现象和改进的方向。该研究旨在构建都市游憩空间的有机结构,为城市规划与游憩管理提供科学依据。 相似文献
4.
Ole H. Caspersen MSc PhD. Cecil C. Konijnendijk Anton S. Olafsson 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):7-20
Geografisk Tidsskrift, Danish Journal of Geography 106(2):7–20, 2006 In its Regional Plan of 2005, The Greater Copenhagen Authority (abbreviated as “HUR” in Danish) places special emphasis on the future recreational values associated with the regional green structure. In this paper, the development of the urban green structure in Greater Copenhagen is elaborated upon, focusing on land use changes and the effectiveness of regionally coordinated planning measures. EU MOLAND data are used to analyse the development of the region's green structure during the period 1954 to 1998. Analysis of two “green wedges” within the green structure illustrates that the development of the green recreational areas is the result of both formal and more informal planning initiatives. Development has shown equal phases that correspond to the applied regional planning measures and the general economic conditions. However, local preferences in the involved municipalities likewise have played an important role and have resulted in different urbanisation pressure within the two wedges. Land use has transformed from an agricultural to a primarily recreational landscape. In some areas, however, urbanisation pressure has resulted in residential and green industrial areas instead of the planned recreational land use. Based on its historical development it is concluded that future preservation and development of the green structure in Greater Copenhagen requires regional planning measures to be incorporated into municipal plans. In this way the increasingly independent municipalities will comply to objectives of the Regional Plan 2005. 相似文献
5.
A case study of land cover change (1950-2003) and runoff in a Mediterranean catchment 总被引：2，自引：0，他引：2
Dennis M. Fox Emmanuelle WitzViolaine Blanc Cécile SouliéMarc Penalver-Navarro Alain Dervieux 《Applied geography (Sevenoaks, England)》2012,32(2):810-821
Mediterranean environments have been subject to major land cover change since the end of the second world war. Housing, agricultural activities, forests, green spaces and other land uses have shifted due to urbanisation and tourism. These changes influence runoff, and municipal authorities often cannot estimate the net impact of complex land cover transitions. During this period, elected representatives have become increasingly sensitive to the risks of flooding and have implemented a number of channel management strategies. The main objective of this case study was to analyse the impact of land cover change on total storm runoff between 1950 and 2003 in a Mediterranean catchment near St Tropez, France. A secondary objective was to compare these changes to the impacts of channel management on bankfull discharge. Aerial photographs were used to classify land cover in 3 urban categories, vineyards and bare soil, forests, and green spaces. Stream discharge was estimated using a distributed event based total runoff approach. After validating the model for a large winter event (114 mm) for 1982, runoff was calculated for the same event for 1950 and 2003. Land cover changes occurred mainly in the alluvial plain area. Total gauge catchment urban area increased from 30.1 ha to 393.8 between 1950 and 2003 at the expense mainly of agricultural land, but this was compensated in part by an increase in grassed area. Some of the loss in vineyards was replaced by clearing forested land on the first hills close to the plain. Bank stabilisation and channel maintenance since the 1980’s reduced surface roughness and increased channel area, thereby greatly increasing bankfull discharge. While the impact of urbanisation on runoff was small, channel management effects increased bankfull discharge substantially. Flood damage from extreme events was not studied here. 相似文献
6.
1990~2005年间,是广州市经济快速发展和城市景观变化最大的时期,以同时段TM影像解译得到广州市的土地覆被类型图,从数量结构、空间信息及位置转移和景观等方面,分析了广州市土地覆被的动态特征.数量结构的研究结果显示:在快速城市化过程中广州市的耕地、林地等自然资源的利用程度在加大,自1995年起,这种变化的趋势开始减缓;土地覆被类型之间的信息与位置的转移变化频繁,并且表现出空间位置分异的特征.景观特征指数分析结果表明:广州市城市土地覆被向破碎化方向发展,城市建设用地呈扩展之势. 相似文献
7.
快速城市化过程中城市土地覆被的时空动态特征 总被引：6，自引：0，他引：6
1990—2005年间，是广州市经济快速发展和城市景观变化最大的时期，以同时段TM影像解译得到广州市的土地覆被类型图，从数量结构、空间信息及位置转移和景观等方面，分析了广州市土地覆被的动态特征．数量结构的研究结果显示：在快速城市化过程中广州市的耕地、林地等自然资源的利用程度在加大，自1995年起，这种变化的趋势开始减缓；土地覆被类型之间的信息与位置的转移变化频繁，并且表现出空间位置分异的特征．景观特征指数分析结果表明：广州市城市土地覆被向破碎化方向发展，城市建设用地呈扩展之势． 相似文献
8.
北京中心城区内涝成因 总被引：2，自引：1，他引：1
城市化的发展改变了原始的自然水文循环系统,打破了水量的均衡而导致了城市内涝。本文梳理了应对雨水的基本模式,并总结出与城市规划相关的三方面主要致涝因素——城市土地利用、水系统和基础设施。以北京中心城区为案例,综合考虑城市用地变化过程,从城市基本汇水区单元的视角出发,分析城区内涝程度和上述三方面因素之间的关联规律。结果表明平均坡度、河网密度与城市内涝程度呈线性正相关;耕地比率、林地比率、荒地比率与城市内涝程度呈线性负相关;而不透水表面比率和建设用地比率与城市内涝程度呈指数正相关关系。 相似文献
9.
区位通达性与在京外资企业的区位选择 总被引：9，自引：4，他引：5
利用北京市第二次基本单位普查资料,以邮政编码区为空间单元,采用泊松回归模型探讨了在京外资企业的城市内区位选择及其影响因素。研究涵盖了2001年全部的在京外资企业,模型估计中有效样本240个。外资企业具有显著的向中心城区集聚的分布态势,相对于制造业而言,服务业外资企业更为集中。分析结果表明,区位的通达性和城市结构对在京外资企业区位选择具有显著的影响。接近高速公路、高等院校、外国使馆以及工业园区等对外资企业具有显著吸引作用,离城市中心、火车站和机场距离过远则不利于吸引各类外资企业。研究也发现,制造业外资企业和服务业外资企业以及投资来源地不同的外资企业,在进行城市内部区位选择时存在显著的差异。 相似文献
10.
西苕溪流域不同土地类型下氮元素输移过程 总被引：60，自引：3，他引：60
以西苕溪流域为研究对象,选择最有代表性的5种土地类型,模拟天然大暴雨,通过3次重复实验研究不同形态氮素随暴雨径流及径流沉积物的迁移过程,估算氮素在流域内不同土地利用/土地覆被条件下的损失率。研究结果表明,在相同的降雨条件下,氮素的流失速率和流失量随土地利用/土地覆被类型的不同表现出明显差异,地表径流水相总氮的流失量桑林最大,水田最小。水相不同形态的氮素流失量亦有所不同,悬浮颗粒态氮占地表径流水相总氮的70 %~90 %,水相溶解态氮的流失量以松林为最高,竹林、桑林和水田接近而且较低,不同类型的水相溶解态氮也随土地利用类型的不同表现出各自的特征。各土地类型单位面积、表层10 cm土壤氮素流失高达4.66~9.40 g·m-2,其中随径流沉积物相迁移的氮素占绝大部分(90 % 以上)。估算出的各土地利用类型总氮流失速率,地表径流水相为2.68~14.48 mg·m-2·min-1,径流沉积物相高达100.01~172.67 mg·m-2·min-1。 相似文献
11.
XIAO Yu GAN Shuang HUANG Mengdong LIU Jia MAO Hui ZHANG Changshun QIN Keyu XIE Gaodi 《资源与生态学报(英文版)》2022,13(5):897-911
As a very important part of the urban ecosystem, the urban green space system plays an active role in maintaining the urban ecosystem stability, providing ecosystem services, and improving the quality of the urban environment. In order to deal with the problems brought about by the deterioration of the urban ecological environment, it is necessary to study and analyze the spatial distribution pattern, evolutionary characteristics and ecosystem services of urban green space to maximize its ecological benefits and comprehensive functions. In this study, we took Beijing urban area as an example, and based on the spatial distribution data of urban green space and remote sensing data, we first calculated the urban green space type transition matrix, landscape pattern index and ecosystem services. Then, we analyzed the changes in urban green space landscape patterns, ecosystem services and their spatial distributions from 2000 to 2020, and studied the interactive relationships between landscape changes and changes in ecosystem services. The results showed three key findings. (1) Beijing’s urban green space construction has achieved remarkable results from 2000 to 2020. The area of green space has increased by 77.41%, mainly from cultivated land and construction land. (2) From 2000 to 2020, the amounts of dust retention, SO2 absorption, NO2 absorption, cooling and humidification, carbon fixation and oxygen release, and rainwater runoff reduction in Beijing's urban green space have shown continuous increases in general. (3) There is a close relationship between urban green space landscape changes and green space ecosystem services, and total area (TA) has the highest correlation with ecosystem services. Except for rainwater runoff reduction, the correlation coefficients between TA and ecosystem services are all higher than 0.85. This research can provide theoretical guidance for optimizing Beijing's green space and determining how to maximize the effect of green space for improving the ecological environment, and ultimately provide a scientific basis for the construction of Beijing's ecological environment. 相似文献
12.
城市化对西安市降水及河流水文过程的影响 总被引：1，自引：1，他引：0
为探究城市化对西安市降水机制及城市河流灞河下游水文过程的影响,根据西安市及灞河1970-2015年水文气象资料以及由遥感影像解译得到的土地利用数据,在分析西安市降水、土地利用特征及灞河下游降水、径流变化特征的基础上,运用水文特征参数时间序列法分析城市化对西安市降水的影响以及灞河水文过程的影响。结果表明：1970-2015灞河降水量呈不显著下降趋势,而径流量呈显著下降趋势;西安市土地利用程度较高,土地利用变化表现为耕地及林地向建设用地转移;受城市化影响,西安市降水机制发生了改变,强降水频次呈增加趋势,且城区增幅大于郊区;降水年内分配不均匀,越来越集中于夏季,增加了城市内涝的威胁;城市化对灞河下游降水-径流关系产生了影响,降水对径流的影响呈减弱趋势,而城市化对径流的影响呈增强趋势;此外,受城市化影响,灞河下游径流量年内波动趋缓,特别是汛期;城市化是影响径流变化的主要因素（61.5%）,降水变化是影响径流变化的次要因素（38.5%）;灞河下游径流量的减流主要是水利工程的作用及过量开采傍河地下水。 相似文献
13.
城市土地利用结构影响因素的通径分析——以重庆市为例 总被引：7，自引：2，他引：5
精确刻画城市用地结构与影响因素间的直接和间接效应对城市土地利用宏观调控和用地结构优化具有重要的意义。采用通径分析法,对重庆市城市土地利用结构与影响因素之间的关系进行定量厘定,结果表明:①人口增长对居住用地比例的直接效应最大(0.446),其通过经济发展、产业结构变化和交通基础设施发展的间接效应分别为-0.189、0.221、-0.042;经济发展、产业结构变化通过人口增长对居住用地的间接效应较大(0.420、0.309)。②产业结构变化、经济发展对工业用地比例的直接效应为-1.357和1.236,对公共服务用地比例的直接效应为1.387、-1.100;人口增长通过经济发展对工业用地比例和公共服务用地比例的间接效应分别为1.163、-1.036,作用方向相反。③经济发展、交通基础设施发展和产业结构变化是影响绿地比例的重要因素;人口增长通过经济发展后的间接效应(0.451)显著于直接效应(-0.117)。④经济发展、产业结构变化和人口增长及三者的耦合作用是影响城市用地结构的主要因素。 相似文献
14.
Land uses and their legacies are a major driver of human impacts on the environment. Decision makers have recognized that the legacies of land-use activities continue to influence ecosystems, particularly aquatic ones, for decades or centuries. The main objectives of this paper are to develop land use legacy maps to (1) assess historical and future (predicted) shifts in dominant land use classes (urban, agriculture, forest) in the Ohio River Basin (ORB), and (2) determine the past and future location of catchments in the ORB exceeding critical land use thresholds (10% and 38% urban and agricultural use of catchment respectively) for water quality and other aquatic resources. Our land use legacy simulations show that approximately 80% of the ORB has remained as agriculture (∼37%), forest (∼34%), urban (∼7%) and other classes (∼2%) from 1930 to 1990. Within the remainder of landscape, agriculture to forest (∼16%) and agriculture to urban (∼1.5%) transitions were the most common land use changes between 1930 and 1990. Our forecast model shows that approximately 94% of the ORB will remain as forest (∼47.46%), agriculture (∼35.77%), urban (∼8.84%) and other classes (∼2.07%) between 2000 and 2050. 1.44% and 1.37% of the ORB is predicted to transition from forest to urban and agriculture to urban between 2000 and 2050, respectively. Our results also demonstrate that 13% and 74% of the catchments in the ORB already exceeded critical urban and agricultural land use thresholds in 1930, respectively. We predict that 37% of catchments in the ORB will have exceeded critical urban land use thresholds by 2050, whereas the proportion of catchments to exceed critical agricultural use will decrease to 45%. 相似文献
15.
中国基础设施与城乡一体化的关联发展 总被引：30，自引：0，他引：30
运用灰色关联分析法,构建了基础设施与城乡一体化关联度模型,进行区域尺度两者的二级指标关联度、标准关联度和动态关联系数的计算,实现了对区域基础设施与城乡一体化关联水平的定量分析。研究结果表明：20年来,中国区域基础设施与城乡一体化发展的关联水平存在着明显的东、中、西空间差异,并随着不同时期区域政策的变化而有所波动。自20世纪70年代末至90年代初,东、中、西梯度差异比较明显,90年代中期这种格局被打破,到2000年出现了更高层面上的东、中、西明显分异。最后,基于不同省区的基础设施与城乡一体化动态关联系数,将全国分为上升型、下降型、U型和小幅波动型四种演化类型,并进行了类型成因分析。 相似文献
16.
公园绿地是城市中重要的绿色基础设施。针对传统可达性分析微观尺度研究不足和交通成本估计失真等问题,以深圳为例,采用公园绿地矢量数据和基于手机SDK（Software Development Kit,软件开发工具包）定位的人口数据作为供需数据源,基于住房分类数据以城中村、保障房、商品房居民划分社会群体,利用改进的高斯两步移动搜寻法计算得到居住小区尺度的公园绿地可达性社会公平情况。研究发现：① 深圳公园绿地可达性存在社会分异：商品房和城中村可达性较好;公租房和安居房社区公园可达性差;人才住房仅对社区公园可达性高;② 驾车可达性最均衡,公共交通方式下不同住房群体间的可达性差异较大。研究补充了中国城市公园绿地可达性社会公平研究的不足,改进了小尺度可达性研究的数据与方法,为公园绿地规划体系提供反思,并可为深圳城市发展提供政策依据。 相似文献
17.
长三角快速城市化地区景观多功能性演变——以苏州市为例 总被引：2，自引：0，他引：2
评估快速城市化地区的景观多功能性演变特征对于理解城乡发展转型下的资源配置与优化、制定合理的区域土地管理与规划政策至关重要。论文以长三角经济区中城市化进程最为突出的代表性城市——苏州市为研究区,选取居住承载、粮食供给、生境维持、水源涵养、气候调节与土壤保持6种景观功能指标,通过空间分析、SOFM网络模型等方法,基于1 km景观单元对区域景观多功能性的热点演变规律、权衡协同演化关系等进行分析。研究表明：① 受城市扩张影响,2000—2015年间苏州市景观多功能以居住承载功能的扩散态势为主,其他景观功能均呈现差异化缩减趋势,其中粮食供给与生境维持的功能弱化最为显著,且3种调节功能的空间分布特征存在一致性。② 随时间推移,苏州市景观多功能性逐渐增强,其高值区(>2)范围集中分布在林草地与耕地景观。在社会经济发展影响下,区域景观多功能性时空演变特征由强到弱并逐渐趋于稳定,演变热点区主要分布在乡村地区与城乡结合部,冷点区则以生态空间集聚为主。③ 景观多功能之间权衡与协同关系在研究期内的特征规律并未因时间序列演进表现出差异性,但权衡与协同程度存在波动性变化趋势。结合多功能权衡特征与多功能性热点变化规律,可在景观单元与乡镇行政单元上将苏州市划分出8类主导景观功能与4类城乡发展分区。整体而言,长三角快速城市化地区的景观多功能性优势呈“城市→近郊区→远郊区→乡村”的圈层式空间迁移过程,但多功能性映射出的土地利用多样化势必会导致更多的土地利用冲突问题,决策者应在多尺度时空耦合视角综合考虑景观管理或土地利用政策的设计与实施。 相似文献
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太湖流域浙西区不同土地类型的面源污染产出 总被引：34，自引：1，他引：33
以太湖流域浙西水利分区为研究区,采用Arcgis的水文分析模块,对浙西区进行流域划分,选取以单一农业用地为主的子流域,利用GIS叠加分析方法,获取各子流域的降水、径流深度、土地利用结构信息,分析研究区主要土地利用类型与径流量的统计关系,建立该区年尺度的径流估算模型。基于林地、耕地为主的子流域水质监测数据,结合径流估算模型,分析占该区90%土地利用面积的林地、耕地与径流污染物浓度的定量关系,研究结果显示,该研究区以林地为主的流域径流各水环境指标为：COD浓度为2.95 mg/l,BOD浓度为1.080 mg/l,总氮浓度为0.715 mg/l,总磷浓度为0.039 mg/l;耕地为主的流域径流水环境指标为：COD浓度为5.721mg/l,BOD浓度为3.097 mg/l,总氮浓度为2.092 mg/l,总磷浓度为0.166 mg/l。这一研究结果适合应用于太湖流域上游山区、丘陵地区年尺度面源污染估算。 相似文献
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Yelena Ogneva-Himmelberger Hamil Pearsall Rahul Rakshit 《Applied geography (Sevenoaks, England)》2009,29(4):478-487
Several studies indicate that there is a positive relationship between green vegetation land cover and wealthy socio-economic conditions in urban areas. The purpose of this research is to test for and explore spatial variation in the relationship between socio-economic and green vegetation land cover across urban, suburban, and rural areas, using geographically weighted regression (GWR). The analysis was conducted at the census block group level for Massachusetts, using Census 2000 data and impervious surface data at 1-m resolution. To explore regional variations in the relationship, four scenarios were generated by regressing each of the following socio-economic variables – median household income, percentage of poverty, percentage of minority population, and median home value – against two environmental variables – percent of impervious surface and population density. GWR results show that there is a considerable spatial variation in the character and the strength of the relationship for each model. There are two main conclusions in this study. First, the impervious surface is generally a strong predictor of the level of wealth as measured by four variables included in the analysis, at the scale of census block group; however, the strength of the relationship varies geographically. Second, GWR, not ordinary least squares technique, should be used for regional scale spatial analysis because it is able to account for local effects and shows geographical variation in the strength of the relationship. 相似文献