نتایج جستجو برای: vegetation density

تعداد نتایج: 453936  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه تربیت مدرس - دانشکده منابع طبیعی و علوم دریایی 1388

this research was conducted in two protect and destroy region in the middle zagros, in illam province. in order to identification of ecological species group and evaluate density of regeneration, effect of many factors such as protection, vegetation, physiographic factors, physical and chemical properties of soil in study locations were studied. to achieve these purpose number of 54 plots using...

Risks assessment of forest project implementation in spatial density changes of forest under canopy vegetation using artificial neural network modeling approach   Nowadays, environmental risk assessment has been defined as one of the effective in environmental planning and policy making. Considering the position and structure of vegetation on the forest floor, the main role of forest under ca...

Vegetation in any landscape reflects its health condition. Monitoring land use change and land cover plays a key role in environmental planning and management. Mazandaran province has always been considered by tourists due to its high tourism potential and consequently the vegetation, especially the forest, has been damaged. In this study, vegetation Contiguity and integrity in Mazandaran using...

رویان, ملوک, سلمان ماهینی, عبدالرسول, سپهری, عادل,

Remote sensing and aerial photography are means of exploring, studying and estimating vegetation variables such as species frequency and density in forests and rangelands. Common remote sensing images usually offer general information about vegetation parameters. For detailed information about vegetation (e.g. estimation of vegetation density and/or frequency), larger scale images are needed. T...

2015
Lobina G. Palamuleni Agnes K. Turyahikayo

In arid and semi-arid environments like the rest parts of South Africa, the state of vegetation density in catchments is an important indicator of the state of the environment. Climate variability coupled with different anthropogenic activities could affect vegetation cover at varying levels. The Upper Molopo River Catchment (UMRC) in the North West Province of South Africa is under this combin...

Journal: Desert 2019
H. Azarnivand H. Khosravi, M. Behrang Manesh P. Dehghana S. Ahmadi

     Drought is a disaster phenomenon especially in arid and semi-arid areas. Vegetation and its production play a main role in the social and economic issues in every country. In this study, Standardized Precipitation Index (SPI) and Normalized Difference Vegetation Index (NDVI) data have been used to monitor drought and the vegetation condition in Sonqor Abad in, Kermanshah province.  Meteoro...

Sistan has recently confronted to periodic drought and water scarcity that destroyed vital resources especially vegetation. Information about reaction of the vegetation species to drought is necessary for protecting and biological restoring this ecosystem, so density of Tamarix aphylla, Salix babylonica and Eucalyptus were investigated using quadrates 50m × 50 m during wet (1366-1376) and droug...

2006
M. Straatsma

Floodplain roughness parameterization is one of the key elements of hydrodynamic modeling of river flow, which is directly linked to safety level estimation of lowland fluvial areas. Necessary input parameters are median grain size for unvegetated areas, vegetation density for forest and vegetation height and density for herbaceous vegetation. This paper presents a method for spatially distribu...

Journal: :journal of rangeland science 2015
amir mirzaei mossivand farshad keivan behjou ehsan zandi esfahan ardavan ghorbani

the aim of this study was to assess the regional effects of fire on the surface cover and forage production of mountainous rangelands of delfan county, lorestan province, iran. the fire took placed in june 2007 with significant effects on the vegetation characteristics in the study area. four fire affected sites were selected for sampling and a close area without fire was considered as control....

2001
Francesca Pozzi Christopher Small

The objective of this study is to investigate the consistency of “suburban” population densities and land covers. We analyzed population density, extracted from the census, and vegetation abundance, derived from Landsat imagery, taking six cities in the U.S.A. as contrasting examples. Combining population density and areal vegetation abundance estimates yields univariate and bivariate distribut...

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