共查询到19条相似文献,搜索用时 196 毫秒
1.
Landscape structure is often regarded as an important factor that governs the distribution and abundance of species.Therefore it is critical to understand the landscapes and their dynamics.Patterns of landscape elements strongly influence the ecological characteristics.This study was designed to document and map the current status of the tropical dry deciduous forest of the Tadoba-Andhari Tiger Reserve(TATR),Central India,(using IRS P6 LISS IV data)and to describe its landscape structure at three levels of organization viz.landscape,class,and patch.The study area was classified into 10 land cover classes that include 6vegetation classes.The landscape structure was analyzed using FRAGSTATS using 12 set of indices.The TATR landscapes have a total of2,307 patches with a mean patch size of 25.67 ha and patch density of 1.7patches per km2.Amongst all land cover classes,mixed bamboo forest is dominant—it occupied maximum area(77.99%)—while riparian forest is least represented(0.32%).Mixed forest has maximum number of patches among all vegetation classes.Results have shown that despite being dominant in the area,mixed bamboo forest has low patch density(0.25/100 ha).Dominance of mixed bamboo forest is attributed to large patch sizes and not to the number of patches.This study has focussed on the approach of integrating satellite forest classification and forest inventory data for studying forest landscape patterns. 相似文献
2.
一个世纪来黑龙江省森林景观动态研究 总被引:1,自引:0,他引:1
With the help of GIS tool of ARC/INFO,ARCVIEW and FRAGSTATS,the map of forest resource distribution of Heilongjiang Province was analyzed in 1896,1949 and 1981.Using total area,mean patch size,patch density,coefficient of patch size variation,mean patch fractal dimension and mean shape index,we studied the change of forest landscape pattem and the change of each patch types in this region.As a result,the total area of forest landscape and mean patch size decreased sharply,the quantity and density of patches increased,the juxtaposition of patches weakened,the shape of patch tended to become regular,and the border of patch simplified.All these showed that the forest landscape of this area tended to fragment gradually,and the fragment of Korean pine forest is the severest.the diversity of whole forest landscape and the eveness of landscape types distribution reduced gradually.Human impact,instead of climate change and forest community succession,is the most important reason for such dramatic chages. 相似文献
3.
The population structure and regeneration status of Magnolia punduana Hk. f. & Th., an endemic tree species of northeast India were investigated in fragmented forests in the Jarain Hills and in adjoining areas of Meghalaya state. The population structure was discontinuous in all the fragments with the absence of individuals in higher diameter classes. The number of individuals increased with the size of the fragment patches(p < 0.004). The density of mature trees(≥5 cm dbh) was high(24–30 individuals ha-1) in the largest fragment(>105 ha). The number of seedlings and saplings were also higher in the larger fragments. Human-related disturbances had a negative impact on the species population(p<0.002). Variation in the population density in different forest patches has been attributed to fragment size, site characteristics and ongoing human disturbances. The restricted distribution of the species coupled withexploitation and habitat destruction underlines the need for its conservation. 相似文献
4.
LIShu-juan SUIYu-zheng FENGHai-qing WANGFeng-you LIYu-wen 《林业研究》2004,15(3):181-186
Mao‘ershan region is a representative natural secondary forested region in the eastern mountainous region, northeast of China. Under the support of ARC/INFO, the landscape pattern and landscape diversity of Mao‘erhshan region were sudied by combining the forest type map (1:10 000), which was drawn from the aerial photographs (1999), field investigation and land utilization map (1:10 000). The selected indices included patch number, patch size, patch density index, richness index,dominance index, evenness index and diversity index. The results showed that the landscape dominant forest type in Mao‘ershan region was softwood broad-leaved forest. In all landscape types, the average patch area of natural secondary forests was bigger than that of artificial forest. The patch density index of each landscape formed in artificial forest was higher than that of natural secondary forest. The landscape diversity index and landscape evenness index of natural forest were highest, the landscape heterogeneity was also, but the landscape dominance was lower. In natural forest, the control effects of landscape elements on landscape-structure, function and its change were weakened. The artificial forest was on the contrary. 相似文献
5.
LISHu-juan SUIYu-zheng SUNZhi-hu WANGFeng-you LIYu-wen 《林业研究》2005,16(1):i002-i003
Mao‘ershan region is a representative natural secondary forested region in the eastern mountainous region, northeast of China.Under the support of ARC/INFO and GIS technology, the landscape shape and fragment indices of Mao‘ershan experimental plantation were studied by combining the forest type map (1:10000), which was drawn from the aerial photographs (1999), field investigation (1999) and soil utilized map (1:10000). The results showed that the shape index and shape fragment index of natural landscape were higher than those of artificial landscapes and landscape patch fragment index depended on the number of patches. The natural forest had complex shape,suffering little jamming, and its shape index was higher than that of artificial forest. The manual controlled landscape (e.g. nursery, cropland and cutting blank) had regular shape, and its shape index was smaller. The fragment index of patches in natural forest was higher than that of artificial forest. The soft broad-leaved had the highest fragment index of patch amount. 相似文献
6.
Post-fire habitat restoration of sables during winter season in northern slope of the Great Xing'an Mountains 总被引:1,自引:0,他引:1
XIE Fu-ju LI Xiu-zhen XIAO Du-ning Hong S. He 《林业研究》2006,17(3):231-237
Habitat loss and fragmentation have been associated with the decline of endangered species. In 1987, a catastrophic fire in the northern Great Hing'an Mountains of China, where the main habitat of sables (Martes zibellina) is located, aggravated the loss and fragmentation of the forest landscape. Due to restricted distribution and low population density, sables were listed in the national first-grade protected species in China. The objective of this paper was to identify to what extent the habitat of sables had been restored 13 years after the fire. Based on the behavioral data, which came from field survey information by radio-tracking, GPS (Global Positioning System) and forest inventory data, suitability habitat maps were derived using the Ecological Niche Suitability Model (ENSM). In addition, the habitat structure was analyzed with selected landscape indices. Although forest cover mostly had been restored by 2000, the results indicated that, compared to the pre-fire situation, the areas of suitable habitat had been reduced significantly, especially those of less suitable, marginally suitable and moderately suitable designation. Fragmentation was aggravated, and suitable patches were found to be further isolated with the exception of those in most suitable areas. The ratio of the patch perimeter to area in unsuitable, moderately suitable and suitable areas decreased, while the ratios within other suitability types increased. Moreover, the percentage of soft boundaries decreased slightly, which can influence the redistribution of sables. The results above indicated that the suitable habitat had deteriorated, and the restoration of the sables' habitat remained to be done. 相似文献
7.
Effects of environmental factors on species richness patterns of herb layer in Eastern Zhongtiao Mountain 总被引:1,自引:0,他引:1
LIU Qiu-feng KANG Mu-yi WANG Hao LIU Quan-ru 《林业研究》2005,16(3):175-180
The species richness of herb layer was investigated among 43 plots of forest vegetation in the eastern Zhongtiao Mountain, in southern Shanxi Province, China. The forest vegetation was divided into two major vegetation types such as the deciduous forest and the coniferous forest by the two-way indicator species analysis (TWINSPAN). The species richness of herb layer was fitted in the topographic and soil feature factors, as well as the topographic relative moisture index (TRMI) by the generalized linear models (GLM). The results showed that canopy cover and altitude were the most significant environmental factors. Soil pH value and soil nutrients index such as total N, organic matter content had no significant influence. The effect of environment factors on species richness of herb layer had significant difference in vegetation types. For the broad-leaved forest, litter depth and TRMI were the important environment factors. For the coniferous forest, soil clay content was another important environment factor. The range of environmental gradient such as altitude may contribute to the difference. 相似文献
8.
ZHANGFengchun LUQi 《中国林业科技(英文版)》2004,3(4):1-11
Ecosystem degradation occurs in parallel with desertification process in sandy areas of North China. The vast sandy areas in North China are characterized with flexible environments and fragile ecosystems as well as intensive human activities. Due to the annual precipitation gradient decreases from east to west in North China, the whole sandy region falls into 3 main climatic zones: arid, semi-arid and dry sub-humid zones.The ecosystems in each type of climatic zones are different in climatic conditions, human activities, cultural dimensions, vegetation covers, landscapes, and causes and processes of ecosystem degradation. Therefore, the most effective rehabilitation measures of degraded ecosystems in different types of the climatic zones are also different. For the arid sandy areas, vegetation rehabilitation of degraded ecosystems needs to be completely closed, assisting with artificial measures, such as plantation, irrigation or others. For semi-arid sandy areas, the effective measures of vegetation re 相似文献
9.
《林业研究》2016,(2)
Natural, protected areas offer many possibilities for recreation in rural areas such as camping, one of the most popular activities. The system established for protected areas in Turkey aims to provide a foundation for conserving areas for recreation. One such area, Abant Natural Park, is convenient for visits from Turkey's two most populated metropolitan areas, Istanbul and Ankara. It also attracts tourists from other regions and countries. The aim of the present study was to evaluate the vegetation loss and land cover changes due to picnic/camping, transhumance, and construction over 40 years(1966–2004) in the park using data on visitor numbers, vegetation patches,corridors and connectivity. For evaluating landscape variables, remote sensing data and aerial photos were used.When aerial photos were imported into the ERDAS Imagine program, ground control points identified, and individual images orthorectified, land degradation was not found in the use of camping areas. Moreover, manmade areas(road, car park and hotel) observably increased, thus decreasing the forest lands. The findings show that the land use types that have had the greatest ecological impact aretranshumance and construction of hotels, which also require infrastructure development. The intensity of the ecological effects mandates precautions to lessen the impacts and the need for continuing assessment to ensure sustainable use of the area. 相似文献
10.
Guddappa Mahalingappa Devagiri Anil Kumar Khaple Siddagangaiah Mohan Puttanaik Venkateshamurthy Sanjay Tomar Arkalgud Nagaraja Arunkumar Geeta Joshi 《林业研究》2016,27(4):799-810
Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron pinnatum.Gap size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration. 相似文献
11.
l "trod notionViolent human disturbance results in global landscape and vegetation fragmentation, including thepolar landscape and alpine vegetation (Cox, 1993).In modern world, environment and development aretWo important problems, which have a direct effecton the destiny of human and the earth. Forestry,which undertakes double missions that are to optimize the environment and promote the development,is the crux to realize the unity of environment anddevelopment (Liu 1985).China is a develop… 相似文献
12.
景观格局是由自然或人为形成的一系列大小、形状各异,排列不同的景观要素共同作用的结果.利用2005年MODIS卫星数据,经过一系列处理后得到湖南省景观图.利用决策树分类法将研究区分为5种景观类型:水、自然植被、耕地、城镇用地、其它用地.选取斑块数、斑块密度、破碎度、斑块分维数、多样性指数、优势度、均匀度、聚集度、分离度等景观指数,从斑块、斑块类型和景观3个层次上对研究区景观格局进行定量分析.结果表明:湖南省景观斑块共39357块,总面积为21.1984万km2;在5种景观类型中,植被和耕地是主要景观类型,占研究区总面积的88.38%;湖南省景观多样性程度低,且斑块空间形状简单. 相似文献
13.
①斑块特征指数分析表明:各景观类型的密度、分维数指数都较小,植被景观的深展指数都不高,扩散比较均匀,没有极端复杂的形状产生,植被景观在演替系列中还没有普遍达到演替的顶级,斑块之间自相似程度较高。②多样性指数分析表明:总体多样性程度高。景观多样性指数、优势度指数与均匀度指数的结果所包含的意义一致,这种一致性充分说明了各植被景观类型分布均匀,各景观类型地位相差较小。③空间构型指数分析表明:保护区的斑块密度为1.001,即1 km2上有1.001个斑块。这说明斑块数目较少。各景观类型分布也较均匀。保护区景观破碎度指数为0.007,这表明该区植被景观在研究期内所表现的生境破碎化程度是很低的。每一植被景观类型破碎度指数最高的是灌丛和灌草丛景观,其次为栲林景观,其余的破碎度都处于较低的水平。内部生境破碎化指数以灌丛和灌草丛景观、栲林景观为最低,它们的单独斑块面积较大,故破碎化指数较低。其它景观类型的破碎化指数相差不大,这与植被顺向演替是相关的。景观分离度指数的排序结果与斑块密度的排序基本一致。 相似文献
14.
大小兴安岭森林植被交错区在全球气候变化研究中的科学意义(英文) 总被引:1,自引:0,他引:1
大小兴安岭是我国纬度最高的地区,也是我国近百年来温度增加最明显的区域。大小兴安岭森林植被交错区位于东经123°~128°,北纬48°~53°之间。作为温带针阔叶混交林向寒温带针叶林的过渡区域,在全球变化研究中占有重要地位。本文对该交错区的地理位置、地形地貌、气候梯度、土壤类型、植被类型等进行了论述。 相似文献
15.
平潭县植被景观多样性研究 总被引:1,自引:0,他引:1
以平潭岛为研究区域,基于遥感、地理信息系统和景观生态学研究方法,对2003年的TM遥感影像图进行判读,结合实地调查,纠正判读,得到平潭岛植被景观现状图。将data格式转成excel格式,计算出研究区植被景观多样性指数,对其进行分析。结果表明,研究区植被斑块为细粒结构,以中小斑块为主,以农业植被景观为基质;次生相思树林为森林景观的主要组成部分,其面积和斑块数为4918.6410hm^2和96块,占景观总面积和总斑块教的16.33%和20.04%;研究区内植被分布不均匀,多样性水平低,景观异质性较差。 相似文献
16.
《Scandinavian Journal of Forest Research》2012,27(7):651-667
AbstractAltered forest landscape structure has been suggested as a possible cause for the decline of some specialized forest species in Fennoscandia. Here, we present a time series of boreal landscape changes in 1954–2005 in 16 5×5 km sub-areas in Sweden, based on aerial photo interpretation. We explored how coniferous forest vegetation types, known to be important to some specialized forest species, have been fragmented and also declined in mean patch size and their proportion of the landscape. We divided the studied area into a western (inland) and eastern (coastal) part based on different timing of landscape changes. The mean patch area of forest >50 yrs declined from ~90 ha in 1954 to 10 ha in 2005 in the inland and from 30 ha to only ~5 ha patches in the coastal area. Common vegetation types, such as mesic and moist forest >50 yrs showed a similar declining trend. In our study area, the long-term decline 1971–2005 of the specialized forest species grey-sided vole (Myodes rufocanus) coincided with the decline of mean focal patch size of forest >50 yrs. The data presented here can be used in further analyses of species–landscape interactions along spatiotemporal gradients. 相似文献
17.
Niu Jianzhi* Gao Jiarong Wang Fengyou College of Soil Water Conservation Beijing Forestry University Beijing P. R. China Heilongjiang Forestry Department Harbin P. R. China 《中国林学(英文版)》2003,5(4)
1IntroductionLandscapeisaregionconsistingofmanydifferenthetero-ecosystems.Theindividualeco-system抯structureandfunctionoflandscapewillchangeunderdifferentspatialandtemporalconditions,becausetheyareaffectedbyvariousfactors,suchasexchangeprocessofenergy,mattersandorganisms,biologicalandabiologicalactions,andhumanactivities.Landscapedynamicchangeisoneofthekeyresearchissuesoflandscapeecology(FormanandGodron1986,NavehandLiebermann1993,Sun1995).Itisgenerallyreflectedbyquantitativelyanalyzinglandsc… 相似文献
18.
利用Quickbird和ETM影像对浙江省绍兴县北部平原220 km2区域内50个村庄景观格局热效应进行了研究。通过环境亮温与建筑、水体、草地、林地、绿地(草地+林地)5种地类斑块共45个景观指数间的数量关系分析,结果表明:各景观指数与环境亮温间具有良好的线性关系;众多景观指数可分为密度类指数、覆盖率类指数、形状指数、核心区规模指数、100 m缓冲区相关指数、其它指数6类,其中优势斑块和景观总体的密度类指数、覆盖率类指数是环境亮温的主要作用因子;有关建筑斑块及核心区景观总体规模的指数(建筑的覆盖率、块均面积、聚合度,核心区的总面积、总周长、总块均面积)与环境亮温为正相关关系,其它多为负相关,因此建成区规模较小、各地类以众多小斑块均匀分布、建筑覆盖率低且形状狭长的村庄更有助于环境降温。建立了4个亮温预测模型(Ra2>0.9),筛选出相应的亮温预测及调控因子组;在核心区,环境亮温的单因子拟合效果欠佳,景观格局结构指数的作用不能忽略,结构指数对亮温的作用贡献约占总量的25%。 相似文献
19.
利用1995年和2007年两期TM和ETM遥感影像数据,结合实地调查,研究了重庆市主城区20世纪90年代中期以来绿地景观格局时空变化特点与成因,讨论了不同绿地类型景观区域格局变化。结果表明,(1)重庆成直辖市以来,研究区整体上绿地景观多样性增加,优势度下降,破碎化增加,景观结构变化呈上升趋势。(2)有林地和其他林地比重减轻,景观破碎度增加;高覆盖度草地面积增加明显,破碎化轻微增加,低覆盖草地破碎化降低。(3)绿地景观斑块形状较规则,其中林地景观斑块形状更复杂,属研究区内优势植被类型。(4)研究区内绿地景观同非绿地景观类型间转化明显,表明其受到较强烈的干扰。其中在海拔200 m以下、坡度6&#176;下城市绿地受到干扰最强烈。北碚区和沙坪坝区内绿地景观年变化速率最高。(5)自然灾害(火灾和酸雨)和人为经济、社会活动(包括植被经营和管理、旅游开发和其他人为干扰活动等)是研究时段内绿地景观格局变化主要驱动因素。 相似文献