We evaluated the effects of livestock grazing on C content of the plant-soil system (to 60 cm) of two semi-arid grasslands: a mixed-grass prairie (grazed 12 years), and a short-grass steppe (grazed 56 years). Grazing treatments included season-long grazing at heavy and light stocking rates, and non-grazed exclosures. Significantly higher soil C (0-30cm) was measured in grazed pastures compared ...

In many arid and semi-arid regions, collapsible soils are well-known to be problematic in nature negatively affect the performance of engineering structures. Gypseous soil considers one types soil. It represents a real challenge engineers due different problems encountered by projects implemented this The mineralogy, composition, fabric gypseous its ability deform when subjected wetting (due ch...

Contrary to wetlands or moderate climates, the understanding of carbon exchange between ecosystem and atmosphere in arid and semi-arid environments is more challenging due to the sensible feedback of terrestrial ecosystems to environmental variability. Especially in the savannah regions of South Africa the biomes are strongly affected on the one hand by low and sporadic precipitation and on the...

Gypsum is an excellent source of Ca and S, both of which are required for crop growth. Large amounts of by-product gypsum [Flue gas desulfurization gypsum-(FGDG)] are produced from coal combustion in the United States, but only 4% is used for agricultural purposes. The objective of this study was to evaluate the effects of (1) untreated, (2) short-term (4-year annual applications of gypsum tota...

Herbivores are major drivers of ecosystem structure, diversity, and function. Resilient ecosystems therefore require viable herbivore populations in a sustainable balance with environmental resource availability. This balance is becoming harder to achieve, with increasingly threatened species reliant on small protected areas in increasingly harsh and unpredictable environments. Arid environment...

Human arsenic exposure from rice consumption is a global concern. Due to the vast areas of naturally contaminated soils in rice-producing regions, the only possibility for reducing hazardous exposure is to prevent As uptake and translocation to rice grain. Sulfur inhibits As mobility both in soil and plant, indicating that soil S content may be a primary factor controlling As uptake; indeed, gy...

The objective of the study was to provide a model to predict the uptake of arsenic and mercury by plants in response to coal combustion byproducts (CCB) application rates to soil, based on CCB/soil characteristics as determined by sequential extraction of the amended soil. Two greenhouse studies were conducted. The first study consisted of sorghum sudan grass, sunflower, and brake fern, an arse...

Wild jujube, Ziziphus lotus, is a multipurpose xerophytic shrub of the Rhamnaceae family widely distributed in arid and semi-arid regions of Tunisia, where it occupies most soil types. The fruit is the edible part of the plant by local population. The reintroduction of this shrub requires the control of its multiplication in response to water shortage. This study aims to evaluate growth and wat...