Rangelands are uncultivated lands that include grasslands, savannahs, steppes, shrub lands, deserts and tundra. The native vegetation on rangelands is predominantly grasses, forbs and shrubs (Kothmann, 1974). Rangelands cover 31 percent of the land surface area of the United States (Havstad et al., 2009), and up to half of the land surface area worldwide (Lund, 2007). Most land areas that are n...

although the geographic and climatic conditions of the desert itself is not really growing, knowing about the iranian desert is important. what expands the deserts is the relationship of the desert areas with of the natural environment itself. degradation of water resources, soil and especially vegetation in the desert belt of iran provided conditions caused desertification and their spread on ...

Chinese temperate grasslands play an important role in the terrestrial carbon cycle. Based on the parameterization and validation of Terrestrial Ecosystem Model (TEM, Version 5.0), we analyzed the carbon budgets of Chinese temperate grasslands and their responses to historical atmospheric CO2 concentration and climate variability during 1951–2007. The results indicated that Chinese temperate gr...

Algae are very large and diverse group of simple, typically autotrophic organisms that can carried out photosynthesis and have ability to capture energy from sunlight. Algae play an important role in sustainable and organic agriculture where it is used as biofertilizer and soil stabilizers. Algae, particularly the seaweeds, are used as fertilizers, resulting in less nitrogen and phosphorous run...

For the first time, an assessment of phenotypic variability and genetic polymorphism was performed on endemic plants Scutellaria tuvensis Juz. growing in Tuva (five populations; Russia). Based morphological traits individuals, principal component analysis clustered individuals into three groups depending characteristics their habitats: group 1 turned out to be sampled from beach gravel, 2 a det...

the jirds, meriones persicus and m. libycus are two widespread species in iran. meriones libycus can be found in low lands of deserts and semi desert areas, but meriones persicus in high rocky regions of khorasan. in this research 190 skulls belonging to meriones persicus and meriones libycus of northeast of iran were at first identified on the basis of morphologic characters, and then were div...