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1.
Landscape spatial pattern mainly refers to the distribution of patches, which are different in size and shape in space owing to the interaction of various ecological activities. In landscape ecology study, landscape pattern has been one of the key study areas. Water body landscape plays an important role in the development history of a city, but at present city water body landscape in many cities has been destroyed, hence protecting water body in the city is becoming more and more important. In order to protect city water body landscape reasonably, the precondition is to probe the dynamics of water body landscape. Based on historical data and remote sensing data, six indexes including patch number, patch area, landscape dominance index, fractal dimension, patch density and connectivity index etc. were used to analyze landscape pattern dynamics of water body in Kaifeng city since the end of the Qing Dynasty (in the 20th century). The results showed: (1) Since the end of the Qing Dynasty, landscape area of water body in Kaifeng city increased first and then decreased from 1898 to 2002AD; the landscape dominant degree had the same changing tendency with the area. (2) Patch number of water body landscape in Kaifeng city had an increase from 1898 to 2002, but maximum area of patch, minimum area of patch and average area of patch decreased, which resulted in an increase in landscape fragment degree. (3) Connectivity index decreased and fractal dimension increased from 1898 to 2002. The reasons for these changes were the repeated overflows and flooding of the Yellow River and the influence of human activities.  相似文献   

2.
1984-2008年北京湿地景观格局驱动机制(英文)   总被引：3，自引：0，他引：3  
The landscape pattern of Beijing wetlands has undergone a significant change as a result of natural and artificial elements.Supported by remote sensing and GIS technology,using multi-temporal TM images from 1984 to 2008 in Beijing,this paper analyzed the dynamic characteristics of wetlands landscape pattern through selected typical indices including patch area,patch average area,fractal dimension index,diversity,dominance,contagion indices and the spatial centroids of each wetlands type were calculated.Finally,the paper explored the evolution mode and driving factors of wetland landscape pattern.The results were obtained as follows:the total wetland area increased during the period 1984-1996,then decline from 1996 to 2004.The wetland area in 1994 accounted for only 47.37% of that in 2004.The proportion of artificial wetland area was larger than that of natural wetland.The proportion of reservoir wetland was 33.50% to 53.73% and had the maximum average area.pond and paddy field wetland type with the least average area accounted for 16.46% to 45.09% of the total wetland area.The driving forces of the natural river wetland were mainly natural elements;its fractal dimension index was greater than the others.The Shannon diversity index of wetland landscape increased from 1.11 in 1992 to 1.34 in 2004,indicating that the difference between proportions of each wetland type decreased and areas of each wetland type were evenly distributed.The contagion index went down from 65.59 to 58.41,indicating that the connectivity degraded.Miyun Reservoir had the largest area and its area change had a great impact on the location of the centroid.Wetland resources degenerated gradually from the joint effects of natural and artificial factors.During the period 2006-2008,the precipitation increased and the drought condition was relieved.The government implemented series of positive policies to save water resources,and the wetland area increased.  相似文献   

3.
Yangshao culture is the most important mid-Holocene Neolithic culture in the Yellow River catchment,and thus,a study on the impact of human activities on the environment is important.In the current study,the distribution pattern of the cultivated land in late Yangshao culture is reconstructed using GIS tool and site domain analysis(SDA).The results show that the cultivated land during 5.5-5.0 ka BP was mainly distributed in the Weihe River valley,Luohe River valley,northwestern Henan Plain,Fenhe River valley and eastern Gansu region,especially concentrated in the Xi’an-Baoji line of the Weihe River valley.At that time,at least 37,000 km 2 of lands were reclaimed in the middle and lower reaches of the Yellow River,and 132,000 km 2 of lands were affected by agricultural activities.Human activities had become the driving force of land use/land coverage.Charcoal records indicate that the ancestors of Yangshao culture burnt forests for reclamation,leading to the decrease of arbor pollen at 5 ka BP in core areas of the Yangshao culture.The areas that were significantly affected by human activities accounted for 3.2% of the Yangshao culture influenced area,while the moderately affected areas accounted for 20.1% of Yangshao culture influenced area.Meanwhile,92% of the land areas on the edge and outside of the Yangshao culture influenced area were not affected by human activities.The arbor pollen in these areas did not decrease until 4.0 ka BP.  相似文献   

4.
The reservoir wetland, which is the largest artificial wetland in Beijing, constitutes one of the important urban ecological infrastructures. Considering two elements of natural environment and socio-economy, this paper established the driving factor indexing system of Beijing reservoir wetland evolution. Natural environment driving factors include precipitation, temperature, entry water and groundwater depth; social economic driving factors include resident population, urbanization rate and per capita GDP. Using multi-temporal Landsat TM images from 1984 to 2010 in Beijing, the spatial extent and the distribution of Beijing reservoir wetlands were extracted, and the change of the wetland area about the three decade years were analyzed. Logistic regression model was used to explore for each of the three periods： from 1984 to 1998, from 1998 to 2004 and from 2004 to 2010. The results showed that the leading driving factors and their influences on reservoir wetland evolution were different for each period. During 1984-1998, two natural environment indices： average annual precipitation and entry water index were the major factors driving the increase in wetland area with the contribution rate of Logistic regression being 5.78 and 3.50, respectively, and caused the wetland growth from total area of 104.93 km 2 to 219.96 km 2 . From 1998 to 2004, as the impact of human activities intensified the main driving factors were the number of residents, groundwater depth and urbanization rate with the contribution rate of Logistic regression 9.41, 9.18, and 7.77, respectively, and caused the wetland shrinkage rapidly from the total area of 219.96 km 2 to 95.71 km 2 . During 2004-2010, reservoir wetland evolution was impacted by both natural and socio-economic factors, and the dominant driving factors were urbanization rate and precipitation with the contribution rate of 6.62 and 4.22, respectively, and caused the wetland total area growth slightly to 109.73 km 2 .  相似文献   

5.
近60年黄河水沙变化及其对三角洲沉积的影响   总被引：1，自引：1，他引：0  
In order to find out the variation process of water-sediment and its effect on the Yellow River Delta, the water discharge and sediment load at Lijin from 1950 to 2007 and the decrease of water discharge and sediment load in the Yellow River Basin caused by human disturbances were analyzed by means of statistics. It was shown that the water discharge and sediment load into the sea were decreasing from 1950 to 2007 with serious fluctuation. The human activities were the main cause for decrease of water discharge and sediment load into the sea. From 1950 to 2005, the average annual reduction of water discharge and sediment load by means of water-soil conservation practices were 2.02×109 m3 and 3.41×108 t respectively, and the average annual volume by water abstraction for industry and agriculture were 2.52×1010 m3 and 2.42×108 t respectively. The average sediment trapped by Sanmenxia Reservoir was 1.45×108 t from 1960 to 2007, and the average sediment retention of Xiaolangdi Reservoir was 2.398×108 t from 1997 to 2007. Compared to the data records at Huanyuankou, the water discharge and sediment load into the sea decreased with siltation in the lower reaches and increased with scouring in the lower reaches. The coastline near river mouth extended and the delta area increased when the ratio of accumulative sediment load and accumulative water discharge into the sea (SSCT) is 25.4–26.0 kg/m3 in different time periods. However, the sharp decrease of water discharge and sediment load into the sea in recent years, especially the Yellow River into the sea at Qing 8, the entire Yellow River Delta has turned into erosion from siltation, and the time for a reversal of the state was about 1997.  相似文献   

6.
The study employs slope,aspect,relief degree of land surface,land use,vegetation index,hydrology and climate,as evaluation indexes to set up the Human Settlements Environmental Index(HEI) model to evaluate the environmental suitability for human settlements in the Shiyang River Basin.By using GIS spatial analysis technology,such as spatial overlay analysis,buffer analysis and density analysis,the environmental suitability of the human settlement spatial situation and spatial pattern are established to analyze their spatial distribution.The results show that the index of suitability for human settlements in the Shiyang River Basin is between 17.13 and 84.32.In general,suitability for human settlements decreases from the southwest to the northeast.Seen from an area pattern,the suitable region is mainly distributed in the Minqin oasis,Wuwei oasis and Changning basin,which are about 1080.01 km 2 and account for 2.59% of the total area.Rather and comparatively suitable region is mainly distributed around the counties of Gulang,Yongchang and north of Tianzhu,which is about 1100.30 km 2.The common suitable region is mainly distributed outside the counties of Yongchang,Jinchuan and most parts of Minqin County,which are about 23328.04 km 2,accounting for 56.08% of the total area.The unsuitable region is mainly distributed upstream and to the north of the river,which is about 9937.60 km 2,accounting for 23.89% of the total area.Meanwhile,the least suitable region is distributed around the Qilian Mountains,which are covered by snow and cold desert and lie in the intersecting area between the Tengger Desert and Badain Jaran Desert.The total area is about 6154.05 km 2,accounting for 14.79% of the total area.Suitable regions for human habitation are mainly distributed around rivers in the form of ribbons and batches,while others are scattered.The distribution pattern is identical to the residential spatial pattern.In addition,the relationships between HEI and other factors have been analyzed.There is a clear logarithmic correlation between the residential environment and population,that is,the correlation coefficient between the evaluation value and population density reaches 0.851.There is also a positive correlation between the residential environment and economy,which reaches an evaluation value of 0.845 between the residential environment and GDP.Results also show that the environment is out of bearing with the existing population in Shiyang River Basin.Spatial distribution of population is profoundly affected by severe environmental problems,such as the expanded deserts,the hilly terrain and the changing climate.Surface water shortage and slow economic growth are bottlenecks for suitable human settlement in the Shiyang River Basin.Combining these problems with planning for construction of new country and the exploitation of local land,some residential areas should be relocated to improve the residential environment.  相似文献   

7.
Yanchi County is located in the agro-pastoral ecotone and belongs to the ecologically fragile area of Northwest China.It is important to study the evolution of landscape pattern to curb its environmental degradation.In order to intuitively show how the landscape pattern of the study area changes over time,Landsat Thematic Mappers(TM)and Landsat Operational Land Imager(OLI)data of 1991,2000,2010 and 2017 were used.This paper attempts to apply niche theories and methods into landscape ecology,and constructs a niche model of landscape components by using"n-dimentional hypervolume niche theory"and landscape pattern indices.By evaluating the spatial and temporal evolution of niche from the perspective of two-dimensional space to reflect the changes of landscape pattern in the study area over the past 26 years,new theories and methods were introduced for the characterization of landscape pattern.The results indicate that:1)The larger the attribute and dominance value of landscape components,the higher the ecological niche and the stronger the control effect on the overall landscape.2)The ecological niche of each landscape component was significantly different,just as its control effect on the overall landscape.3)The dynamic change of the ecological niche of each landscape component was different,with grassland,unused land and arable land always in a high dominant position,although the ecological niche of construction land and water area was always low.In general,the introduction of niche theory into the landscape ecology provided a new method to study the changes in regional landscape pattern.  相似文献   

8.
土地覆盖与气候变化对黄河源区径流的影响   总被引：1，自引：1，他引：0  
After dividing the source regions of the Yellow River into 38 sub-basins, the paper made use of the SWAT model to simulate streamflow with validation and calibration of the observed yearly and monthly runoff data from the Tangnag hydrological station, and simulation results are satisfactory.Five land-cover scenario models and 24 sets of temperature and precipitation combinations were established to simulate annual runoff and runoff depth under different scenarios. The simulation shows that with the increasing of vegetation coverage annual runoff increases and evapotranspiration decreases in the basin. When temperature decreases by 2℃ and precipitation increases by 20%,catchment runoff will increase by 39.69%, which is the largest situation among all scenarios.  相似文献   

9.
1989-2003年中国北方土地覆被变化   总被引：2，自引：0，他引：2  
The 13 provinces （autonomous regions and municipalities） in northern China are located in latitude 31°-54°N and longitude 73°-136°E including Beijing, Tianjin, Hebei, Shanxi, Inner Mongolia, Jilin, Liaoning, Heilongjiang, Shaanxi, Gansu, Ningxia, Qinghai, and Xinjiang, where environments are fragile. In recent years, the eco-environmental problems such as vegetation destruction, desertification and soil erosion etc. become serious because of climate change and unreasonable human activities. In this paper, landscape pattern and its evolution in northern China from 1989 to 2003 was investigated by the combined use of RS and GIS based on the basic theory and method of landscape ecology. Land use/cover maps of the study area in 1989, 1999 and 2003 were produced by using 1 km monthly NOAA Advanced Very High Resolution Radiometer （AVHRR） and SPOTNGT Normalized Difference Vegetation Index （NDVI） dataset from national climate bureau of China which were geo-registered to Lambert azimuthal equal-area map projection and were used in the paper. Landscape evolution in the area over the study period was investigated by two methods： （a） the changes of various landscape metrics were analyzed using the landscape structure analysis program FRAGSTATS; （b） the transition matrix of landscape patch types was calculated with the help of the RS and GIS software. The results showed that from 1989 to 2003, the landscape within the study area had undertaken a complicated evolution in landscape structure and composition. The diversity index and evenness index increased during the period, which means that the landscape pattern tended to be diversified and even. The fragmentation index of grassland, forestland and water areas also increased significantly. This showed that the distribution and structure of forestland, grassland and water areas had been changed greatly during the period, especially grassland which became more and more fragmentized, and its fragmentation index increased from 19.23% to 88.72%. The transi  相似文献   

10.
The middle reaches of the Yellow River represent an important area for the protection and development of the Yellow River Basin. Most of the area of the river basin is within the Loess Plateau, which establishes it as a fragile ecological environment. Firstly, using high-resolution data of land use in the watershed from the past 30 years, landscape ecological risk(LER) sample units are defined and an ecological risk index(ERI) model is constructed. Kriging interpolation is used to display the LE...  相似文献   

11.
By using GIS and remote sensing techniques, the paper discusses how human activities have changed along the Yellow River in Henan province, China and how these altered activities have influenced the wetland landscape pattern change from 1987 to 2002. Results show that the total area of the wetland reduces dramatically compared to 1987, the total area of wetland reduces by 19.18%, the number of the patches in 2002 increases by 21.17%, the density increases by 50%, and the total perimeter increases by 1,290,491 m. Disturbed by human activities, landscape diversity index decreases from 1.1740 in 1987 to 0.9803 in 2002. During the last 20 years, the total area of the rice wetland increases, while the others decrease. Among those, the area of the bulrush wetland decreases most. In 1987, it takes 0.5% of the total area, but in 2002, it only takes 0.11%. The interpenetration of human influences on the wetland natural system has been long and close. The impacts of human activities on the spatial pattern of the wetland landscape along the Yellow River in Henan from 1987 to 2002 are great.  相似文献   

12.
近20年来河南沿黄湿地景观格局演化   总被引：61，自引：7，他引：54  
丁圣彦  梁国付 《地理学报》2004,59(5):653-661
在遥感和GIS技术的支持下,结合河南沿黄湿地的区域特点,确定了河南沿黄湿地景观分类系统,通过采用景观多样性指数、优势度、景观破碎化指数、分布质心和扩展度等景观的空间格局指数,比较系统地分析了近20年河南沿黄湿地景观空间格局变化。结果表明：(1) 河南沿黄湿地的分布面积呈显著下降趋势。1987~2002年湿地面积减少了19.18 %,斑块数量增加了21.27 %,斑块密度净增加0.5倍。斑块总边缘增加了129 0491 m,斑块平均边缘减少了117.84 m。(2) 随着人类干扰强度增加,景观多样性下降,优势度增高。研究区景观多样性指数1987年为1.174,2002年降为0.9803,优势度指数由1987年的0.4355提高到2002年的0.6291。湿地的破碎化程度随着湿地面积的减小和斑块数量的增加,其破碎化程度越来越大,破碎化指数由1987年的0.0141增加到2002年的0.0172。(3) 湿地景观要素中,稻田湿地面积在增加,而水库坑塘、河流、滩地、荒草沼泽地面积都在不断减少,其中荒草沼泽 (芦苇沼泽) 湿地面积减少幅度最大。1987年荒草沼泽湿地占整个湿地地区的0.5%,但到2002年只占0.11%。表明近20年来,人类活动对河南沿黄湿地景观格局变化的影响程度较大。  相似文献   

13.
河南黄河沿岸地区景观格局演变   总被引：18，自引：0，他引：18  
梁国付  丁圣彦 《地理学报》2005,60(4):665-672
利用1987年和2002年的遥感影像,借助于地理信息系统技术,结合河南黄河沿岸的区域特征,运用景观生态学的基本理论,分析河南黄河沿岸地区景观格局的演变,用于了解在自然过程和人类活动共同作用下的河南黄河沿岸地区景观格局的演变过程及影响机理。结果表明,在研究区域内,水浇地景观类型为占优势的景观类型。1987~2002年景观格局动态变化显著：河流景观、水浇地景观、林地景观和滩地景观类型的面积呈减小趋势,坑塘景观、稻田景观、旱地景观和建设用地景观类型面积则呈增加趋势。景观斑块总数量呈现出略微减少的趋势。景观空间特征表现为景观多样性增加,各景观类型所占比例差异减小。破碎化指数减小,景观整体破碎化程度有所减缓。景观空间构型明显,基本上是以大斑块为主,呈聚集型分布。特别是占优势的景观类型,斑块更加集中连片。自然过程特别是人类活动对河南黄河沿岸地区景观格局的变化有深刻的影响。  相似文献   

14.
黄河三角洲滨海湿地的景观格局空间演变分析   总被引：18，自引：0，他引：18  
利用GIS技术、RS影像和Fragstats3.3等景观统计软件,从景观面积变化、景观斑块特征和景观整体水平格局等方面,对比研究了黄河三角洲2000年和2009年湿地不同时空尺度的景观格局变化。结果表明:10 a间黄河三角洲滨海湿地海岸线和陆地面积整体呈增长趋势,天然湿地面积急剧减少,平均分维数大部分降低,湿地景观破碎度降低,多样性和均匀性指数增加,蔓延度指数增加。湿地景观格局指数的变化反映了旱田及水田的大面积种植,盐田养殖业的大力发展以及石油开采等人为活动对景观格局的深刻影响,人类活动已经成为黄河三角洲滨海湿地景观格局变化的主要驱动因子。  相似文献   

15.
Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province.  相似文献   

16.
以朝阳港潟湖湿地为研究区,将朝阳港潟湖湿地景观类型划分为两大类七个亚类,其中自然景观主要包括河口湿地、潟湖浅滩、沼泽和盐碱荒地;人工景观主要包括养殖池、盐田和农用地。1954～2007年的50余年间,朝阳港潟湖湿地景观总体变化趋势是从大斑块、类型较单一的自然景观为主体的景观格局向小斑块、多种景观类型共同控制的景观格局转变,不同时期景观类型及其面积变化的主要驱动因素是人类活动。为了度量人类活动干扰对潟湖湿地的影响,以景观生态学为基础,构建了人类干扰强度模型方法,对1954年以来不同时期人类活动对潟湖湿地的干扰强度进行了量化分析,提出了湿地的人类干扰强度分级标准。研究结果表明,1954～1971年期间,朝阳港潟湖湿地的人类干扰强度为轻微干扰;此后,人类对潟湖湿地的干扰强度为强干扰。对比不同时期人类活动对该潟湖湿地的干扰强度,发现在1972～1983年间人类活动对该潟湖湿地的干扰强度突然增大,该潟湖湿地的开发高峰期主要是20世纪70年代至80年代初。检验结果证明,人类干扰强度模型的计算结果是可信的。  相似文献   

17.
1 Introduction Agriculturallandscape is the m osaics ofnaturaland hum an-managed patches thatvary in size, shape and arrangement(Forman and Gordron,1986).The spatialpattern in the landscape may influence a variety of ecological processes,such as water run…  相似文献   

18.
河南黄河流域湿地面积占河南省湿地总面积的近1/3,保护与恢复湿地是推动生态文明建设的重要举措。分析了河南黄河湿地现状、特点和存在的主要问题,提出了湿地保护和恢复建议,包括提高公众认识、加快湿地保护制度和自然保护区体系建设、加强科学管理等。  相似文献   

19.
滨海湿地是受人类活动影响最显著的地区之一,研究以山东渤海滨海地区为对象,针对1990、2000、2010、2019年遥感影像数据,运用人类活动强度模型和皮尔逊相关系数等方法,探究人类活动影响下滨海湿地演变规律,揭示人类活动与土地利用类型的一般关系,得出以下结论：（1）1990—2019年研究区湿地面积总体增加,人工湿地显著增加,自然湿地显著减少,大面积自然湿地向人工湿地转化,其中黄河三角洲是研究区内自然湿地保留最完好的地区;（2）1990—2019年人类活动强度不断增加,平均值由1990年的8.48上升至2019年的17.07,增幅为101.30%;在不同人类活动强度区,湿地对其起到的主导作用与强弱程度成反比;（3）研究期内,伴随盐田及建设用地面积的不断增加和自然湿地向其他地类的转化,人类活动中-高强度区湿地面积总量较少但不断增加,低强度区湿地面积不断减少但总量较多;（4）从各城市相关性检验结果来看,不同城市人类活动影响因素与湿地面积的相关性存在一定差异,总体上人类活动影响因素与人工湿地呈显著相关,与自然湿地呈显著负相关或不相关。研究可为山东渤海滨海地区湿地保护及应对人为过度开发湿地的行为提供科学依据和重要借鉴。  相似文献   

20.
1988～2002年开封市景观动态变化   总被引：26，自引：2，他引：24  
在遥感和GIS技术的支持下,通过采用分维数、多样性指数、破碎度指数和边界密度等指数,分析了1988～2002年开封市景观动态变化。结果表明:（1）研究区斑块数增加,由1988年的28784个增加到2002年的32311个;景观破碎度增大;景观形状趋于复杂。（2）建设用地、水域和城市绿地面积增加;耕地（主要是水浇地）、未利用土地和园地等面积减小。（3）建设用地的空间质心向西南方向转移,城市绿地的空间质心向东北方向转移,水域空间质心向东南方向转移。（4）在景观斑块之间,高密度建设用地转移很少,保持较高的稳定性;低密度建设用地主要转为高密度建设用地;而旱地、水浇地等耕地主要转变为低密度建设用地;未利用土地主要转移为旱地、城市绿地和水域。人类活动和黄河同时控制着开封城市发展方向、发展策略和景观类型之间的转化等方面。  相似文献   

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