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1.
城市化进程改变了区域的景观结构,引起了景观格局的变化。以大长山岛两期景观分布图为数据源,运用景观生态学的理论与方法,利用景观格局指数定量分析了1995~2006年景观格局的动态变化特征,在此基础上借助CA-Markov模型对大长山岛2017年景观格局进行了模拟与预测,并探讨了景观格局演变驱动机制。结果表明:大长山岛在快速城市化的进程中,景观格局演变的总规律为自然景观向人文景观转变。1995~2006年间,主要表现为农用地、草地、商业及工矿用地面积减少,园林地、水体及水利设施、居民点及公共服务和其它用地增加;而2006~2017年间,表现为农用地、草地、园林地面积减少,居民点及公共服务、水体及水利设施、商业及工矿用地和其它用地增加,但在此期间各景观类型的面积减少和增加的速度有所放缓。  相似文献   

2.
景观格局决定了陆域污染物的源汇过程,是影响河流水质状况的关键因素.由于尺度效应,不同尺度下景观格局与河流水质关系的研究结果不尽相同.然而,景观格局对河流水质影响的尺度效应问题尚缺乏系统研究.收集了国内外4 041条研究数据,采用Meta分析法定量分析了不同尺度下景观格局对河流水质的作用特征,识别了影响河流水质的关键时间和空间尺度以及景观指数.结果表明,相对于降水事件、平水期和年际尺度,丰水期下景观格局对河流水质的影响最大;相对于流域尺度,缓冲区尺度的景观格局对河流水质的影响更大;丰水期-缓冲区尺度是景观格局影响河流水质的关键时空耦合尺度.与耕地、水域、草地以及流域整体景观相比,林地和城镇用地的景观格局对河流水质的影响更大;破碎度是影响河流水质最重要的景观格局因子.在河流水质治理中,应重点考虑缓冲区的景观配置,增加缓冲区林地面积、减少林地和水域的斑块密度和减少城镇用地的面积占比和聚集度,以有效保护河流水质.  相似文献   

3.
淮南矿区土地利用变化对区域景观格局的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
以淮南矿区5期遥感影像图作为基本信息源,利用土地利用转移矩阵和景观格局指数分析了淮南矿区的土地利用变化及其对区域景观格局的影响。土地利用变化相关结果表明:1980 — 2015年淮南矿区及区域土地利用变化主要表现为耕地的减少,建设用地、水域的增加。矿区耕地面积减少117.6 km~2,其中46.7%的面积转换成建设用地,51.2%转换成塌陷水域,其所在区域(流域)耕地减少了274.4 km~2,有63.1%转换成建设用地,33.1%转换成水域。将矿区增加的塌陷水域面积还原作为无采矿活动的对照,分析采矿活动对区域景观格局的影响,结果表明:采矿活动使得区域景观多样性指数增加了0.07,矿区土地利用变化使得区域景观多样性增加、优势度减小,区域景观格局更加趋于多样、均衡。  相似文献   

4.
中国国家公园建设潜在区域识别研究   总被引:9,自引:4,他引:5  
虞虎  钟林生  曾瑜皙 《自然资源学报》2018,33(10):1766-1780
国家公园是保护具有国家代表性资源的自然生态区域,建设国家公园体制是中国国土生态安全保障和生态文明体制改革的重要内容。论文基于国际经验、国家公园功能和政策内涵,依据国家公园主导定位和生态系统服务理念,构建了包含6个关键指标的综合评价模型,包括生态系统完整性、生态重要性、原真性、生物多样性、自然景观价值与人文遗产价值,分别进行单一要素层评价和多指标空间叠加分析,再结合中国生态地理区划、生态功能区划和省级行政区管理等因素进行比对和范围遴选提取,初步确定了中国国家公园建设的潜在区域。结果表明,生态系统完整性、生态重要性、生物多样性、原真性的高值集聚区域具有趋同性,生态系统完整性较好的区域,承担着重要的生态功能,生物多样性也较高,原真性保存较好。中国三大阶梯与自然地理区域的叠加分布特征明显,东西部潜在区域的面积差异较大,西部地区的空间连续性较强,潜在区域的跨界性较为明显。初步遴选出55处未来可以重点考虑建设的陆地型国家公园潜在区域。研究可为中国国家公园建设合理布局提供方法参考和理论借鉴。  相似文献   

5.
丘陵林地土壤酸化修复在维持林地生态系统生产力稳定中具有重要地位.本试验通过在丘陵林地坡顶集中施用石灰、污水污泥和联合施用石灰+污水污泥3种土壤酸化改良剂,研究了3种改良剂对丘陵林地酸化土壤的修复效果.结果表明:①联合施用污水污泥+石灰能够显著(P<0.05)降低土壤酸度,促进土壤有机质和氮素含量快速上升,增加土壤阳离子交换量(CEC),从而有效改良丘陵林地酸化土壤;②土壤改良剂在丘陵林地上坡位集中施用,能够通过径流和泥沙随坡体向下坡迁移的自然扩散机制,使丘陵大面积酸化土壤得到修复;③将城市污水污泥用于丘陵酸化土壤的修复,有利于解决城市污水污泥的污染问题,但只限于非经济林酸化土壤的恢复.  相似文献   

6.
草原区作为影响我国陆地生态系统碳水循环和生态安全的重点区域,对气候变化和人类活动极为敏感.然而,有关气候变化和人类活动对该区域植被恢复相对贡献的认识尚存分歧.以生态系统净初级生产力(NPP)为评价指标,通过对比MODIS观测的实际NPP和基于Thornthwaite Memorial模型估算的潜在NPP的趋势差异,量化了2000~2020年气候变化和人类活动对我国典型草原区(北方温性草原区和青藏高原高寒草原区)植被恢复的相对作用.结果表明,研究区内93%的草地植被呈恢复趋势,NPP平均增加速率达(以C计)2.12 g·(m2·a)-1(P<0.01),其中,近一半植被恢复区受气候变化和人为活动共同控制,约36%和10%植被恢复区分别受气候变化和人类活动的独立控制;此外,不同草地类型气候变化主导植被恢复的面积占比差异大,主要表现为高寒草地明显高于温性草地,气候条件越干旱,气候主导面积占比越大.人类活动不是北方温性草原区和青藏高原高寒草原区植被恢复的主要原因,但在气候条件恶化地区,人类活动可降低甚至抵消气候变化对植被的负面影响.未来需加强长...  相似文献   

7.
The barn owl Tyto alba has been in decline throughout much of its range largely as a consequence of loss of foraging habitat resulting from agricultural intensification. The recent introduction of agri-environment schemes in the UK has resulted in the reinstatement of substantial areas of rough grassland which may be of benefit to small mammals and their avian predators. In this study mature grasslands provided by agri-environmental schemes (farm woodlands, permanent set-aside, 2 and 6 m field margins) were compared to better understand which hold the greatest prey numbers and how new areas of grassland targeted at barn owl conservation should be created and managed. In all habitats apart from farm woodlands, small mammal numbers were positively associated with taller swards. This study suggests that areas cut every 2 or 3 years supported more individuals and species than areas cut annually, although this trend was only significant for common shrews. With the introduction of the new Environmental Stewardship scheme in 2005, our results suggest that the area of suitable foraging habitat for barn owls is likely to increase.  相似文献   

8.
Naturalresources(landform ,geology ,hydrology,creature ,ecologyetc .) ,humanresources (culture ,economy,locationetc .)andlandscapeecologicalspatialstructureofacertainplacecandetermineitsdevelopmentpatternsandlandscapearchitectureaswellasitslimitationofdevelopm…  相似文献   

9.
以研究区2000 年TM影像、1:50 000 地形图和1:250 000DEM为基础数据源, 运用景观斑块 分布与多样性特征指数, 测算了黔西南中低山丘原盆谷区不同岩性和地貌类型下景观格局特征。结 果表明: ①灌木林地、疏林地、中覆盖度草地占据着景观中的优势地位, 是明显的景观基质, 控制着 区域景观生态格局及其发展。景观斑块类型在不同岩石和地貌类型区存在较明显差异; ②在连续性 灰岩区、灰岩与碎屑岩互层区和灰岩夹碎屑岩区形成的山间盆地和高原台面上以及北部水热丰富 的河谷地带, 水田、旱地、疏林地、低覆盖度草地集中分布, 浅中切割低山类型中有林地和灌木林地 集中分布; ③在连续性白云岩区形成的深切割( 低、中和高) 丘陵、浅切割( 低、中和高) 丘陵, 低覆盖 度草地和灌木林地集中分布; ④从岩溶石漠化、土壤侵蚀、森林退化的空间格局及其组合来看, 在形 成生态环境的区域差异过程中, 岩性和地貌的空间组合结构起着显著的控制作用。  相似文献   

10.
This article establishes a set of indicators and standards for landscape ecological sensitivity analysis of site resources by using the theories and approaches of landscape ecology.It uses landscape diversity index(H),evenness(E),natural degree(N),contrast degree(C) to study spatial structure and landscape heterogeneity of site resources and thus provides a qualitative-quantitative evaluation method for land planning and management of small ,medium scale areas.The analysis of Yantian District,Shenzhen of China showed that Wutong Mountain belonged to high lanscape ecological sensitivity area,Sanzhoutian Reservoir and Shangping Reservoir were medium landscape sensitivity area and high ecological sensitivity area;Dameisha and Xiaomeisha belonged to medium sensitivity area caused by the decline of natural ecological areas.Shatoujiao,Yantian Pier belonged to low sensitivity area but urban landscape ecological development had reshaped and influenced their landscape ecological roles in a great extent.Suggestions on planning,protection goals an development intensity of each site or district were raised.  相似文献   

11.
本研究于2019-2020年对辽宁滨海(环渤海)湿地开展了春迁徙季、秋迁徙季、繁殖季和越冬季的鸟类多样性调查,共监测到鸟类150种,隶属于16目38科,其中,留鸟25种,夏侯鸟26种,冬侯鸟26种,旅鸟73种;国家一级保护鸟类11种,国家二级保护鸟类20种。调查显示:调查区内鸟类多样性的季节差异明显,春、秋迁徙季,鸟类种类与数量明显高于其他两季,越冬季鸟类的种类数量均最少,丰富度指数、均匀度指数、多样性指数和优势度指数均最低。空间分布显示,盘锦地区鸟类种类和数量均最多,达到78种,473084只;营口地区调查到的鸟类种类最少,为55种;锦州地区鸟类数量最少,只有57723只。从鸟类多样性对比来看,盘锦地区最高,大连地区最低,各地鸟类群落组成的空间差异较为明显,在一定程度上受到该地区鸟类生境种类数量及面积大小的影响。辽宁滨海(环渤海)湿地作为东亚—澳大利西亚候鸟迁徙带上的关键区域,当前正面临气候变化、人类围垦干扰造成的鸟类栖息地减少等不利情况,建议通过扩大保护范围、实施修复和管理对策措施、强化宣传等手段保护鸟类多样性及其栖息生境,巩固渤海综合治理攻坚战的治理成效。  相似文献   

12.
Ecosystems are essential in providing multiple services to society. However, understanding ecosystem services (ESS) in terms of spatial distribution and trade-offs still remains a challenge for landscape planners and natural resource managers. In this paper, we analyzed the supply of a set of ESS – carbon storage, soil erosion protection, biodiversity, and recreation – within the landscape surrounding the city of Bari in Southern Italy. Through an analysis of this landscape, which includes natural protected areas, such as Natura 2000 Network sites, national and regional parks and nature reserves, and in view of the recent Fitness Check of the Nature Directives, we aimed to provide answers to the following questions: (i) Where are the areas of high and low supply of individual ecosystem services located?; (ii) Where do ecosystem service trade-offs (i.e., ‘hotspots’ and ‘coldspots’) occur?; and (iii) To what extent are ecosystem service hotspots and coldspots located within or outside of natural protected areas? Results show that most of the landscape in the study area supplied at least one of the selected ESS and that ESS hotspots were mostly located within forested and/or natural areas. Hotspots occupied 8.0% of the total landscape, with 23.7% located in natural protected areas. Coldspots were scarce and equal to 2.4%; they constituted only 0.1% of natural protected areas. Almost all of the landscape (89.6%) consists of intermediate areas (i.e., between hotspots and coldspots); 76.2% of natural protected areas consists of intermediate areas. This latter finding is relevant because the high intermediate classes are potentially high-performing areas, which lie mainly on the borders of protected spaces; they can positively influence ecological processes and thus enhance a wide-ranging provision of ESS. Our results highlight the importance of analyzing landscapes to facilitate the selection of priority areas where management efforts would yield maximum benefits.  相似文献   

13.
利用Landsat遥感数据定量研究了淮河流域1995—2007年间各湿地类型的规模变化,分析了其变化特征,辨识了湿地消长的热点区域,并研究湿地变化热点空间分异的影响因子。结果表明,研究期间流域内水田、库塘等人工湿地大幅增加(净增量分别占1995年湿地总面积的16.81%、4.57%);湖泊、沼泽等自然湿地则明显减少(净减少量分别占1995年湿地总面积的1.06%、2.79%),且多转为人工湿地。湿地变化热点多分布于流域东部及南部;人工湿地变化热点分布连续而集中,自然湿地变化热点则稀少而分散。高程和气温对人工湿地增长热点及自然湿地减少热点的发生影响强度相对较高;社会经济与可达性因素对热点的发生具有显著作用,但其影响强度相对较弱。整个淮河流域,湿地变化热点的发生受多种要素的耦合作用,但湿地变化热点空间分异的首要因素是流域自然地理等背景条件的约束作用。  相似文献   

14.
将盐城国家级自然保护区(新洋港-四卯酉河段)划分为未围区和围垦区,根据1984-2013 年6 个时相的景观资料,运用RS、GIS 技术和景观生态学方法,分析围垦活动影响下海滨湿地景观格局演变差异。结果如下:①未围区始终保持以自然景观为主,2013 年面积比例占84.6%;1984-2013 年,芦苇和互花米草湿地面积分别增长了4 770.6 和4 202.8 hm2,而碱蓬湿地面积减少了2 656.7 hm2。围垦区大致以2000 年为界,景观结构由自然景观占主导转为人工景观为主;除互花米草外自然植被面积呈下降趋势,而人工景观中水产养殖塘面积不断上升,2013 年比例达60.5%。②未围区景观破碎度自1995 年以后变幅较小,且保持在较低水平,维持在0.27~0.28,斑块形状趋于复杂、自然,景观多样性呈上升趋势,1984-2013 年上升了0.19。围垦区破碎化程度上升明显,1984-2013 年上升了0.27,整体景观趋于简单规则,景观多样性呈下降趋势,1984-2013 年下降了0.26。③未围区景观演变驱动力以自然因素为主,景观类型质心移动具有距离较为连续、方向相对单一的特征。而围垦区由于人类活动介入,围垦区景观类型质心移动更多地表现出无序多变、错综复杂的特征。  相似文献   

15.
贵州天然草地资源的自然特征和评价   总被引:1,自引:0,他引:1  
贵州天然草地是我国南方草地资源的重要组成部分。本文通过1984年对贵州省84个县的草地调查和1331个草地调查样地的分析研究,阐述了贵州草地的次生性和不稳定性、草地分布规律、草地植被和草地类型的特点,进而对贵州草地的生产力和开发利用进行了评价。  相似文献   

16.
在遥感和地理信息系统的支持下,通过解译2003年和2013年两个时期的遥感影像,获取闽江河口湿地自然保护区及周边区域的土地景观类型转化数据,确定相应的转移概率矩阵,应用马尔科夫模型模拟研究区域土地景观演变情况.并选取合适的景观格局指数,对闽江河口湿地自然保护区及周边区域的景观格局变化和驱动力进行研究和分析.结果表明:2003~2023年间,随着人类活动强度的增加,闽江河口湿地自然保护区内自然斑块减少,人工斑块增多,景观趋于破碎化、复杂化.海岸线侵蚀、城市扩张、政策导向等是闽江河口湿地及周边区域景观格局变化的主要驱动因素.  相似文献   

17.
1IntroductionLandscapefragmentationanditsimpactsonbiologicaldiversityhavebeenthehighlyconcernedtopicsintherecentyearsbiologi...  相似文献   

18.
As natural woodlands decline in both extent and quality worldwide, there is an increasing recognition of the biodiversity conservation value of production landscapes. In low-input, low-productivity grazing systems in Australia, the modification of natural woodlands through overstorey tree and woody regrowth removal are vegetation management options used by landholders to increase native grass production for livestock grazing; however, there is little empirical evidence to indicate at what tree densities biodiversity attributes are compromised. We examined the effects of overstorey tree density and understorey regowth on the floristic composition, stand structure and species richness of eucalypt woodlands in a grazing landscape in the Traprock region of southern Queensland, Australia. We sampled 47 sites stratified according to vegetation type (Eucalyptus crebra/Eucalyptus dealbata woodland; Eucalyptus melliodora/Eucalyptus microcarpa grassy woodland), density of mature trees (<6 trees/ha; 6–20 trees/ha; >20 trees/ha), and presence/absence of regrowth. Distinct patterns in composition were detected using indicator species analysis and non-metric multidimensional scaling, with low density areas compositionally indistinguishable, although distinct from other land management units. Within vegetation type, medium tree density woodlands were compositionally similar to high density and reference woodlands. Species richness ranged from 18 to 67 species per 500 m2 across all sites. No differences in total or native species richness were detected across management units; however, some differences in exotic species richness were detected. Differences in grass cover existed between low and high density management units, yet no difference in grass cover was evident between low and medium density management units. Our results suggest that medium tree densities may provide biodiversity benefits concordant with more natural areas, yet not adversely impact on pasture production. Retaining trees in grazing landscapes provides significant landscape heterogeneity and important refuges for species that may be largely excluded from open grassland habitats. Maintaining a medium density of overstorey trees in grazed paddocks can provide both production and biodiversity benefits.  相似文献   

19.
Characterizing the paleoenvironmental context of the first hominids is a key issue for understanding their behavioral and morphological evolution. The present study aims at reconstructing the paleoenvironment of the TM266 vertebrate assemblage (Toros-Menalla, Northern Chad) that yielded the earliest known hominid Sahelanthropus tchadensis (7 Ma). For the first time, a quantitative analysis is carried out on the fossil mammal assemblage associated with that hominid. Two complementary approaches were applied: (1) the analysis of the relative abundances of taxa and their habitat preferences; and (2) the study of the distribution of taxa within three meaningful ecovariables: locomotion, feeding preferences, and body mass. The resulting taxonomic and paleoecological structures are used to reconstruct the diversity and the relative extent of the habitats in that part of northern Chad seven million years ago. The paleoenvironment was composed of open areas with dry and humid grasslands, prevailing over wooded habitats. Water was also widely available as freshwater bodies and certainly swamps. It appears that the high habitat diversity of the landscape is a common feature among paleoenvironments associated with early hominids.  相似文献   

20.
为揭示鸭绿江口滨海湿地景观格局动态,支撑滨海湿地资源保护利用与科学规划,本文以1990、2000、2010和2019年遥感影像为数据源,利用景观格局指数和多元回归分析,对鸭绿江口滨海湿地景观格局变化及其社会驱动力进行分析。结果表明:近30年来芦苇湿地和林地显著萎缩,动态度分别为?1.00%和?1.22%,而水库坑塘、养殖场和建设用地面积大幅增加,动态度分别为5.95%、0.83%和5.29%;与1990年相比,2019年水稻田、养殖场、水库坑塘等人工湿地和建设用地斑块数量和密度增大,芦苇湿地斑块面积和密度、破碎化指数及平均分形维数减小;根据景观多样性指数、均匀度指数等整体景观格局指数,湿地景观动态变化可以以1995年和2010年为节点分为3个阶段,景观多样性指数和均匀度指数的降低以及最大斑块面积指数和蔓延度指数的升高反映了人类活动对景观格局的深刻影响;国民生产总值和水产养殖产量等社会经济指标的提升是景观变化、天然湿地面积减少及景观斑块趋于规则化的主要关联因子。  相似文献   

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