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1.
以我国干旱区典型内陆湖泊流域——新疆艾比湖流域为研究区,对其平原区1990--2005年的景观格局动态变化特征进行了研究。结果表明,1990--2005年,研究区农田、湿地及人居地景观的面积增加,其中以农田景观的面积增加量最大;而林地、草地、沙地、戈壁和盐碱地景观的面积呈减少趋势,其中草地、盐碱地和林地景观面积减少较多;各景观类型中以盐碱地、林地、草地和戈壁的转出率较高,而以农田、人居地的转入率较高;研究区景观组份构成没有大的变化,戈壁依然是研究区景观的基质。景观格局变化对区域生态环境的影响主要表现为:农田斑块数量和面积的增加,加大了区域水资源利用压力;林地、草地斑块面积减少,使得平原区绿洲遭受风沙的危害性增大;沙地、戈壁和盐碱地面积减少,使绿洲不同区域生态环境呈现不同变化特征;湿地斑块面积略有增加,对减少艾比湖流域沙尘危害较为有利。  相似文献   

2.
使用基于地形坡度的土壤侵蚀要素提取方法,选择大别山区商城县为研究区,利用TM/OLI和SPOT 5/GF-1数据得到植被覆盖度和土地利用类型图,并结合DEM数据生成的地形坡度因子,基于GIS/RS提取土壤侵蚀信息及其时空变化量。结果显示,研究区2011年和2016年的土壤侵蚀主要分布在南部中低山地区,以轻度侵蚀为主,分别占总侵蚀面积的81.13%和83.97%;土壤侵蚀主要发生在坡度为5°~25°的区域,且随着坡度增大土壤侵蚀越严重;耕地的土壤侵蚀最严重;2011—2016年间虽然大部分区域土壤侵蚀状况不变,但整体有所加重。  相似文献   

3.
以河南省大别山水土保持国家重点生态功能区为研究区,基于RS与GIS获取2012年和2017年研究区植被覆盖、土地利用、土壤侵蚀等遥感解译数据,从生态功能、生态结构和生态压力3个方面,采用综合指数法,对研究区生态状况进行动态监测与评价。结果表明,2012—2017年间,研究区土地利用结构发生较明显的变化,林草地覆盖率上升9.85%,耕地和建设用地面积比上升13.23%,水域湿地面积比变化不大;植被覆盖指数上升 62.74%,中度以上土壤侵蚀面积比略有增加;生态状况变化度ΔF=4.95,整体生态状况等级由良变为优,生态状况变化度评级为显著变好。  相似文献   

4.
山东省生态环境遥感监测及其动态变化研究   总被引:1,自引:0,他引:1       下载免费PDF全文
应用遥感技术对山东省生态环境进行监测,利用GIS技术对遥感监测结果进行解译与分析,同时对2004年-2006年间山东省生态环境时空动态变化进行了分析与评价。结果表明,山东省生态环境类型以耕地和城乡、工矿、居民用地为主,未利用土地面积极小。其生态环境动态变化的主要特点是耕地、草地面积普遍有小幅度减少,以工交建设用地为主的城乡、工矿、居民用地增加较多,林地、水域面积无明显变化,未利用土地面积有所减少,以盐碱地面积减少为主。  相似文献   

5.
利用1985、2000、2013年遥感影像提取的土地覆盖数据,通过景观格局指数、动态度计算、转移矩阵等,分析1985—2013年我国典型地区各类型生态系统景观格局及其动态变化特征、生态系统相互转化时空变化特征等,揭示1985—2013年生态环境格局变化的特点和规律:一级分类生态系统综合变化率,赣江、闽江、白龙江和岷江上游流域分别为4.7%、3.9%、3.3%和1.7%,生态系统变化强度1985—2000年较缓,2000—2013年更剧烈。1985—2013年典型区生态系统的主要转化方向具有持续性和双向性特征,岷江、白龙江和赣江上游流域退耕还林还草政策效果明显,出现较高比例的耕地转为森林和草地;面积占67.4%生态系统类型变化与耕地生态系统和人工表面生态系统变化有关;生态系统变化具有明显的区域差异,生态变化主要表现为沿主要河流谷地的线状延伸,主要城镇居民点附近生态系统类型变化较为突出,人类活动是典型地区生态系统类型格局变化的主要驱动力;典型区尤其是敏感区应加大退耕还林还草政策,减少人类经济活动,降低洪水泥石流灾害发生的概率和程度。  相似文献   

6.
为建立土壤侵蚀动态变化数据库,本文以土地利用数据、植被覆盖指数、最大风速等值线图和DEM数据为信息源,对干旱荒漠区新疆克拉玛依市2000年和2007年的土壤侵蚀状况进行了动态监测与评价。结果表明,受自然条件和人类活动影响,8年间克拉玛依市土壤侵蚀强度有所增加,变化区域主要集中在克拉玛依市中部平原区。该方法的应用实现了土壤侵蚀的定时定量评价。  相似文献   

7.
为全面了解北京城市湿地的现状及近年来的动态变化情况,利用高分辨率卫星遥感数据,综合运用GIS技术与景观生态学方法,定量分析了北京市6环内的湿地空间格局。结果表明,北京6环内城市湿地以河流湿地和湖库湿地为主;2016—2018年间湿地面积有所下降,2年间减少了126.58 hm2,主要转化为草地,少量转化为建设用地和林地;由于城市外围的开发建设强度较大,5-6环湿地被侵占面积相对较大,而4环内湿地面积的波动较小;2016—2018年,北京城市湿地的斑块密度增加,平均斑块面积有所减小,表明湿地斑块随时间变化呈破碎化的趋势,且从城市中心向城市边缘,湿地斑块的破碎化程度增强。  相似文献   

8.
基于TM影像的桂林市植被覆盖时空动态监测与分析   总被引:1,自引:0,他引:1  
以西部地区中等规模城市——桂林市为例,利用1991、2006年两期TM卫星影像数据,在对原始数据预处理的基础上,提取归一化植被指数(NDVI)。依据混合像元二分模型,生成桂林市所辖5城区的两期植被覆盖度监测分类图像,对区域植被覆盖状况进行时空动态变化分析。结果表明,1991年~2006年间,城市植被覆盖区面积总体呈现下降趋势;在划分的3类植被覆盖类型中,低植被覆盖区面积减少幅度最为明显,中、高植被覆盖区面积有不同程度增长;低植被覆盖区主要分布在城市建成区与一些村镇外围区域,中、高植被覆盖区集中分布在城市远郊地带。此外,随着城市化的迅速发展,城乡各类建设用地面积不断增加,城市边缘地带的绿色植被正逐步被人工景观所取代。  相似文献   

9.
遥感技术在察布查尔县土壤侵蚀调查中的应用   总被引:2,自引:0,他引:2  
彭艳平  杨磊  张圣凯 《干旱环境监测》2010,24(3):148-152,157
依据陆地卫星TM遥感影像资料,在ERDAS软件下,通过室内判读与野外调查相结合的方法,解译出土地利用类型图、植被覆盖度图、坡度图。在建立知识库的基础上,利用土壤侵蚀专家分类系统,快速获得察布查尔县土壤侵蚀分类分级状况,为今后该区域的水土保持工作提供参考和依据。  相似文献   

10.
应用遥感技术对南通市生态环境进行监测,利用GIS技术对遥感监测结果进行解译与分析,同时对2006-2009年南通市生态环境时空动态变化进行了分析与评价.结果表明,南通市生态环境类型以耕地、水域和城乡、工矿、居民用地为主,未利用土地面积极小.其生态环境动态变化的主要特点是耕地面积普遍有小幅度减少,以城镇建设用地为主的城乡、工矿、居民用地增加较多,林地面积无明显变化;未利用土地面积有所减少,以盐碱地面积减少为主,减少的面积主要用于耕地和建设用地.  相似文献   

11.
Understanding spatial variability of dynamic soil attributes provides information for suitably using land and avoiding environmental degradation. In this paper, we examined five neighboring land use types in Indagi Mountain Pass - Cankiri, Turkey to spatially predict variability of the soil organic carbon (SOC), bulk density (BD), textural composition, and soil reaction (pH) as affected by land use changes. Plantation, recreational land, and cropland were the lands converted from the woodland and grassland which were original lands in the study area. Total of 578 disturbed and undisturbed soil samples were taken with irregular intervals from five sites and represented the depths of 0-10 and 10-20 cm. Soil pH and BD had the lower coefficient of variations (CV) while SOC had the highest value for topsoil. Clay content showed greater CV than silt and sand contents. The geostatistics indicated that the soil properties examined were spatially dependent to the different degrees and interpolations using kriging showed the dynamic relationships between soil properties and land use types. The topsoil spatial distribution of SOC highly reflected the changes in the land use types, and kriging anticipated significant decreases of SOC in the recreational land and cropland. Accordingly, BD varied depending on the land use types, and also, the topsoil spatial distribution of BD differed significantly from that of the subsoil. Generally, BD greatly decreased in places where the SOC was relatively higher except in the grassland where overgrazing was the more important factor than SOC to determine BD. The topsoil spatial distributions of clay, silt, and sand contents were rather similar to those of the subsoil. The cropland and grassland were located on the very fine textured soils whereas the woodland and plantation were on the coarse textured soils. Although it was observed a clear pattern for the spatial distributions of the clay and sand changing with land uses, this was not the case for the silt content, which was attributed to the differences of dynamic erosional processes in the area. The spatial distribution of the soil pH agreed with that of the clay content. Soils of the cropland and grassland with higher amounts of clay characteristically binding more cations and having higher buffering capacities had the greater pH values when compared to the soils of other land uses with higher amounts of sand naturally inclined to be washed from the base cations by the rainwater.  相似文献   

12.
There has been increasing concern in highlands of semiarid Turkey that conversion of these systems results in excessive soil erosion, ecosystem degradation, and loss of sustainable resources. An increasing rate of land use/cover changes especially in semiarid mountainous areas has resulted in important effects on physical and ecological processes, causing many regions to undergo accelerated environmental degradation in terms of soil erosion, mass movement and reservoir sedimentation. This paper, therefore, explores the impact of land use changes on land degradation in a linkage to the soil erodibility, RUSLE-K, in Cankiri–Indagi Mountain Pass, Turkey. The characterization of soil erodibility in this ecosystem is important from the standpoint of conserving fragile ecosystems and planning management practices. Five adjacent land uses (cropland, grassland, woodland, plantation, and recreational land) were selected for this research. Analysis of variance showed that soil properties and RUSLE-K statistically changed with land use changes and soils of the recreational land and cropland were more sensitive to water erosion than those of the woodland, grassland, and plantation. This was mainly due to the significant decreases in soil organic matter (SOM) and hydraulic conductivity (HC) in those lands. Additionally, soil samples randomly collected from the depths of 0–10 cm (D 1) and 10–20 cm (D 2) with irregular intervals in an area of 1,200 by 4,200 m sufficiently characterized not only the spatial distribution of soil organic matter (SOM), hydraulic conductivity (HC), clay (C), silt (Si), sand (S) and silt plus very fine sand (Si + VFS) but also the spatial distribution of RUSLE-K as an algebraically estimate of these parameters together with field assessment of soil structure to assess the dynamic relationships between soil properties and land use types. In this study, in order to perform the spatial analyses, the mean sampling intervals were 43, 50, 64, 78, 85 m for woodland, plantation, grassland, recreation, and cropland with the sample numbers of 56, 79, 72, 13, and 69, respectively, resulting in an average interval of 64 m for whole study area. Although nugget effect and nugget effect–sill ratio gave an idea about the sampling design adequacy, the better results are undoubtedly likely by both equi-probable spatial sampling and random sampling representative of all land uses.  相似文献   

13.
决定中国区域生态系统生产能力指数的影响因子主要有两类:一是下垫面的影响,山区、丘陵的生产能力高于平原区,在具备生产能力的土地生态类型中,林地生产能力最高,耕地次之,草地最低;二是气候因子的影响,季风气候决定了我国生态系统生产能力的空间分布.呈现西北-东南逐级递增的趋势,造成这种空间分布的主要因素是季风气候造成的降水空间分布.同时,温度也在一定程度上影响了我国生态系统的生产能力,尤其是东部地区.降水对生态系统生产能力的影响强度较温度大.  相似文献   

14.
Because of their intense vegetation and the fact that they include areas of coastline, deltas situated in the vicinity of big cities are areas of greet attraction for people who wish to get away from in a crowded city. However, deltas, with their fertile soil and unique flora and fauna, need to be protected. In order for the use of such areas to be planned in a sustainable way by local authorities, there is a need for detailed data about these regions. In this study, the changes in land use of the Balçova Delta, which is to the immediate west of Turkey’s third largest city Izmir, from 1957 up to the present day, were investigated. In the study, using aerial photographs taken in 1957, 1976 and 1995 and an IKONOS satellite image from the year 2005, the natural and cultural characteristics of the region and changes in the coastline were determined spatially. Through this study, which aimed to reveal the characteristics of the areas of land already lost as well as the types of land use in the Balçova delta and to determine geographically the remaining areas in need of protection, local authorities were provided with the required data support. Balçova consists of flat and fertile wetland with mainly citrus-fruit orchards and flower-producing green houses. The marsh and lagoon system situated in the coastal areas of the delta provides a habitat for wild life, in particular birds. In the Balçova Delta, which provides feeding and resting for migratory birds, freshwater sources are of vital importance for fauna and flora. The settlement area, which in 1957 was 182 ha, increased 11-fold up to the year 2005 when it reached 2,141 ha. On the other hand, great losses were determined in farming land, olive groves, forest and in the marsh and lagoon system. This unsystematic and rapid urbanization occurring in the study region is not only causing the loss of important agricultural land and wetland, but also lasting water and soil pollution.  相似文献   

15.
In many European mountain regions, natural forest regrowth on abandoned agricultural land and the related consequences for the environment are issues of increasing concern. We developed a spatial statistical model based on multiple geophysical and socio-economic variables to investigate the pattern of natural forest regrowth in the Swiss mountain area between the 1980s and 1990s. Results show that forest regrowth occurred primarily in areas with low temperature sum, intermediate steepness and soil stoniness as well as close to forest edges and relatively close to roads. Model results suggest that regions with weak labor markets are favored in terms of land abandonment and forest regrowth. We could not find an effect of population change on land abandonment and forest regrowth. Therefore, we conclude that decision makers should consider non-linearities in the pattern of forest regrowth and the fact that labor markets have an effect on land abandonment and forest regrowth when designing measures to prevent agricultural land abandonment and natural forest regrowth in the Swiss mountains.  相似文献   

16.
焦作韩王矿塌陷区土壤质量变化规律   总被引:2,自引:1,他引:2  
矿区煤炭开采引起的地表塌陷是土壤质量变化的一个主要原因。本文通过对焦作韩王矿塌陷区的土壤理化、生物特性进行研究,结果表明:(1)随着土壤深度的加深,含水量、有机质含量减小,容重、pH增大;自塌陷坡上坡而下到塌陷盆地中心,含水量依次增大,下坡位置容重和有机质含量最高。(2)塌陷区普遍受到重金属Cu、Pb、Zn、Cd的严重污染。(3)自塌陷坡上坡而下到塌陷盆地中心,不同微生物表现出不同的规律;土壤垂向变化方面,微生物表现出来的规律一致。  相似文献   

17.
Soils play a vital role in the quality of the urban environment and the health of its residents. City soils and street dusts accumulate various contaminants and particularly potentially toxic elements (PTEs) from a variety of human activities. This study investigates the current condition of elemental concentration in the urban soils of Hamedan, the largest and the fastest-growing city in western Iran. Thirty-four composite soil samples were collected from 0 to 10 cm topsoil of various land uses in Hamedan city and were analyzed for total concentration of 63 elements by ICP-MS. The possible sources of elemental loadings were verified using multivariate statistical methods (principal component analysis and cluster analysis) and geochemical indices. The spatial variability of the main PTEs was mapped using geographic information system (GIS) technique. The results revealed a concentration for As, Co, Cr, Mn, Mo, Ni, and V in the soil samples comparable to the background values as well as a range of associations among these elements in a single component suggesting geogenic sources related to geological and pedogenic processes, while the soils mostly presented a moderate to considerable enrichment/contamination of Cd, Zn, Pb, and Sb and moderate enrichment/contamination of Cu, Zn, and Mo. It was found that anthropogenic factors, vehicular traffic in particular, control the concentration of a spectrum of elements that are typical of human activities, i.e., Cd, Cu, Hg, Pb, Sb, and Zn. Lead and Sb were both the most enriched elements in soils with no correlation with land use highlighting general urban emissions over time and the impact of transport networks directly on soil quality. The highest concentrations of As were recorded in the southern part of the city reflecting the influence of metamorphic rocks. The effect of the geological substrate on the Co and Ni contents was confirmed by their maximum concentrations in the city’s marginal areas. However, high spatial variability of urban elements’ contents displayed the contribution of various human activities. In particular, the increased concentration of Cd, Sb, and Pb was found to be consistent with the areas where vehicular traffic is heaviest.  相似文献   

18.
为了科学评估北京市平原区造林工程的生态影响,利用高分卫星数据获取2018—2020年北京市平原区造林面积、分布及变化信息,分析了造林工程的空间格局特征,并采用形态空间格局分析(MSPA)方法及最小累积阻力(MCR)模型,构建了北京市平原区生态网络,通过情景模拟分析造林工程对生态源地、生态廊道产生的影响。结果显示,2018—2020年北京市平原区造林工程主要沿西北东南方向实施,实现了对原有林地资源分布不均衡问题的解决。热点建设区域为北部的延庆及东南部的通州、大兴,呈现由城市边界逐步向市中心蔓延的发展趋势。在不考虑其他因素对土地利用的影响的前提下,造林工程的实施使平原区林地面积增长了9.8%。通过情景模拟发现,造林工程的实施使生态网络向连通、完整、均衡方向发展。其中,生态源地面积增长了131.0 km2,主要生态源地连通性提升了41.1%,生态廊道的分布由主要分布在西北部山区向西北、东南两个方向均有密集分布转变。综上,造林工程的生态环境效应显著,造林工程的实施对生态环境质量改善具有重要意义。  相似文献   

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