نتایج جستجو برای: because of poor vegetation
تعداد نتایج: 21181358 فیلتر نتایج به سال:
The bogs in Northern Michigan are unusual ecosystems that contain a thick layer of peat that separates the surface vegetation from the nutrient-rich groundwater below it. Because of the thick layer of peat, nutrient-poor rain is the sole source of water for the surface vegetation, which allows the bog to stay nutrient-poor. In order to measure nutrient dynamics throughout bogs, we decided to in...
To investigate land use changes, Qale Shahrokh basin (15098.1 ha area) was selected. Satellite images of Landsat sensors (MSS, TM and ETM+) were used. After improvement and different enhancement analysis of images such as FCC, PCA, the study area was checked using GPS and topographic maps (1:50000) and other information. Land use units were determined using classified random sampling method. Ma...
To investigate land use changes, Qale Shahrokh basin (15098.1 ha area) was selected. Satellite images of Landsat sensors (MSS, TM and ETM+) were used. After improvement and different enhancement analysis of images such as FCC, PCA, the study area was checked using GPS and topographic maps (1:50000) and other information. Land use units were determined using classified random sampling method. Ma...
In recent decades, land use changes have been one of the most important environmental issues worldwide. This study was carried out to investigate and analyse land use changes in dust sources of south and south-east Ahwaz and surrounding lands using remote sensing technique. Firstly, based on the standard precipitation index (SPI), the years 1986, 2002 and 2016 were selected as years with near n...
in this study, the environmental effects of land use changes on vegetation cover and emitted land surface temperature in two urban and non-urban areas of ardakan in yazd province, iran, were studied and compared temporally, using remote sensing technique. for this purpose, contemporary land sat satellite images in 1990 and 2002 were acquired and used. then vegetation cover maps were generated u...
drought is a major problematic phenomenon mostly for semi-arid areas of iran. during drought periods, reduction in vegetation levels causes such problems as soil erosion, surface runoff, flood risk, etc. therefore, the assessment of drought effects on plant covers is the most important issue. this research was conducted in 2015 using the extracted vegetation indices from moderate resolution ima...
Studying MODIS Satellite Data Capability to Prepare Vegetation Canopy Map in Qazvin Plain Rangelands
Using satellite imagery is a reasonable option to overcome the field visits problems and limitations to evaluate the vegetation cover over the years. The present research has conducted to specify the percentage of vegetation cover of rangelands using Geographic Information System (GIS) and vegetation indices. The study area is located in Qazvin plain rangelands, Iran. In this study, the MODIS s...
abstract cooperative learning refers to small groups of learners working together as a team to solve a problem, complete a task, or accomplish a common goal. in a cooperative environment one’s success is directly related to the success of other members because the focus on the individual shifts towards the group. to test the effectiveness of the method, using jigsaw technique, a study was cond...
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