Features provide a comprehensive global overview of extent and diversity of grasslands. Analyzes how humans shaped grasslands through millennia of use and which role they play in present-day agriculture. Quantifies the role of grasslands as biodiversity hotspots as well as the drivers threatening these. Evaluates the ecosystem services grasslands provide e.g. in terms of soil protection and carbon sequestration. Forecasts the probable future of grasslands under various global change scenarios. Summary Grasslands are one of the most extensive vegetation formations worldwide, occurring in any biome from the Arctic to the tropics, from the sea coasts to the alpine zones, and both naturally and due to human land use. This book explores the creation and use of grasslands by humans from the earliest time to the present and examines the impact of recent human interventions and global warming on their productivity, diversity, and survival. The challenges of conserving biodiversity, maintaining livelihoods of land users while protecting the land, and ensuring sustainable use are highlighted. Grasslands are an important land cover and have a world-wide distribution with grass-dominated communities from the equator to the polar tundra, from the sea level to the alpine zone, and occurring both naturally (such as tropical savannas and temperate steppes) and secondary (as in the cultural landscapes of Europe). Grasslands of the world: diversity, management and conservation, edited by Victor Squires, Jürgen Dengler, Haiying Feng and Hua Limin, is a tribute to these important grass-dominated ecosystems. It was written by international teams of grassland experts, who compiled information from more than 90 countries, in the form of regional syntheses and case studies. تفاصيل المقالة

The major aim of processing satellite images is to prepare topical and effectivemaps. The selection of appropriate classification methods plays an important role. Amongvarious methods existing for image classification, artificial neural network method is ofhigh accuracy. In present study, TM images of 1987, and ETM+ images of 2000 and 2006were analyzed using artificial fuzzy ARTMAP neural network within Mehrgan region,Kermanshah province, Iran, with an area of 5957 ha changes in range cover state in thisbasin during 3 periods of time from 1987 to 2000 and 2000 to 2006 were examined. In thisstudy, initially, Land sat data for intended years were corrected geometrically andradiometric ally. Next, different land use classes were defined and training samplesobtained via field visits. The obtained results show that, over time period of 1987-2000, theextent of low-density rangeland and farmland in study region had been increased by 89.09and 321.08 ha, respectively, while good rangeland and fair rangeland faced a decliningtrend of 358.29 ha and 48.89 ha. Also, during time period of 2000-2006, the extent of poorrangeland and farmland within study region has increased by 64.98 and 727.12 ha,respectively, while good rangeland and fair rangeland faced a declining trend of 144.01 haand 648.1 ha. Accuracy of vegetation maps resulting from satellite data classification usingalgorithm of artificial fuzzy ARTMAP neural network was 90.97% and 94% for TM(1987) images and ETM+ (2000,2006) respectively which indicates high accuracy ofARTMAP algorithms for classifying satellite. Therefore, this study proves high efficiencyand potential of artificial fuzzy ARTMAP neural network for classification of remotesensing images. تفاصيل المقالة

Water resources suitability is one of the most important factors to sustainabilityutilization of natural potential by rangeland grazing suitability. To determine this factor inshort time, low cost and high accuracy are most challenges of experts and ranchers. Usingsuitable technique for this subject can be sustainable utilization comprising from rangelandecosystems according to its degradation and heavy grazing. This research was conducted inBoroujerd Sarab Sefid rangeland, Lorestan province, Iran from 2011 to 2012. Some factorssuch as slope, height and direction maps provided by using satellite images, basicinformation, analog and digitized maps such as; topographic and DEM (Digital ElevationModel). Also measurements of field were conducted by excursion and interview withherders to determine places of water resources such as permanent and temporary springsand permanent and temporary rivers too. Water resources area's map was prepared byusing Arc GIS9.3 software with integration of digitized information and field data. At theend water resources suitability were determined by using three sub models such asquantity, quality and distance from water resources. Results show that all of 16 plantvegetation types were dropped in І and П classes of water resources suitability whichdidn‟t have any limitation according to quantity and quality and distance of animalhusbandry and livestock. As a final conclusion this research shows that using RS and GIScould be useful to water resources suitability of rangeland ecosystems with low cost andhigh accuracy and speed, if consider standards and criteria of using GIS and RS. تفاصيل المقالة

Groundwater is among the most important resources of drinking water supply ofthe worldwide population. Use of recharge area is one of the methods for artificiallyrecharging groundwater. Selection of suitable sites for artificial recharge is very importantand must be carried out accurately. There are different types of land use, only rangelandsare appropriate for artificial recharge because of their topographical situations. In thisstudy, the groundwater artificial recharge suitable area of Silakhor, Borujerd of Iranrangelands was investigated and extracted using Geographic Information System (GIS) andAnalytic Hierarchy Process (AHP) method. The layer information of rainfall, soil,lithology, slope, land use and fault components were prepared and weighed by applyingAHP method and were used for artificial recharge site selection. Aquifer artificial rechargemaps showed that in Silakhor catchment 14%, 64.8% and 21.2% of the area of thecatchment had high, moderate and low capability for artificial recharge, respectively. Themost suitable areas were located in the low land areas. تفاصيل المقالة