Most angiosperms — and all major crops — are unable to withstand high concentrations of sodium chloride. Soils containing concentrations of salt amounting to a few hundred millimolar occur naturally, of course, and saline land is estimated to represent between 2.3 and 6.4% of global land surface [1]. As much as 13% of cultivated land is thought to be salt-affected. In some instances, however, a...

Afforestation of agricultural lands has been one of the major land use changes in China in recent decades. To better understand the effect of such land use change on soil quality, we investigated selected soil physical, chemical and microbial properties (0-15 cm depth) in marginal agricultural land and a chronosequence of poplar (Populus euramericana cv. 'N3016') plantations (5-, 10-, 15- and 2...

Land degradation is a major threat to the sustainability of human habitation, and it is essential to assess it quantitatively. Assessment of the human-induced aspect is especially important for planning appropriate prevention measures. This paper used the Three-North Shelter Forest Program region as the study area, and assessed the land degradation dynamic using a time series of summed normaliz...

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General Comments: This manuscript, “Atmospheric reactive nitrogen concentrations at ten sites with contrasting land use in an arid region of Central Asia”, is a good baseline assessment of the concentrations of nitrogenous species for an understudied region of the world, the arid Xinjiang region of China. This study will provide foundational information in understanding air quality over this re...

A large reservoir of bioavailable nitrogen (up to approximately 10(4) kilograms of nitrogen per hectare, as nitrate) has been previously overlooked in studies of global nitrogen distribution. The reservoir has been accumulating in subsoil zones of arid regions throughout the Holocene. Consideration of the subsoil reservoir raises estimates of vadose-zone nitrogen inventories by 14 to 71% for wa...

The arid zone encompasses land that has an imbalance between precipitation and losses through evaporation. Globally, arid zones comprise large part of many countries in the mid-latitudes in both the Northern and the Southern hemispheres. Both Australia and Iran are countries with a large arid zone. This negative water balance in the arid zone affects the type of land use in these countries. At ...

One of the characteristics in Iranian Model of Desertification Potential Assessment (IMDPA) is vegetation. Sincevegetation is very important factor in the degradation of land, so some indices were determined for this item in order toevaluate desertification potential of arid, semi arid and arid sub humid areas of Iran. The indices included vegetationcondition, exploit and revegetation. To calib...

During the 20th century, purely climate climatic factors were rarely responsible for desertification in the Mediterranean region, because droughts are relatively short-lived. Present land degradation in Northern Mediterranean countries is partially due to dramatic land use changes that occurred during the second half of this century and which in many cases lead to an unstable state of ecosystem...