Semi-arid regions

Your facility is located in a semi-arid region of the United States which has an annual precipitation (including snowfall) of 12 inches of rain. (Snowfall should be converted to the equivalent inches of rain assume one foot of snow is equivalent to one inch of rain.) The area covered by your facility is 42 acres (about 170,000 square meters or 1,829,520 square feet). The area of your facility is 50 percent unimproved area, 10 percent asphaltic streets, and 40 percent concrete pavement. 

To promote the use of poor quality water for irrigation, a field research study was conducted in three semi-arid regions with water scarceness in Syria in order to define, under field conditions, the wheat yield response function to irrigation water salinity, the effect of soil texture and structural characteristics on the irrigation water salinity threshold, and to compare this value with the conventional threshold value. 

These results underline the necessity of establishing regional water quality criteria when planning the use of saline water sources for irrigation. These criteria are of primary importance for establishing suitable strategies for the safe use of saline aquifers in Syria and other arid and semi-arid regions. 

Nyhan, J., Hakonson T., and Drennon, B., A water balance study of two landfill cover designs for semi-arid regions, Journal of Environmental Quality, 19, 281-288, 1990. 

Scanlon, B.R., et al., Intercode comparisons for simulating water balance of surficial sediments in semi-arid regions, Water Resources Research, 38 (12), 12, 2002. 

Arid and semi-arid regions are distinguished on the basis of their annual precipitation sums and include ... 

Semi-arid regions with a precipitation sum of 250 to 500 mm/year and a steppe savannah/prairie/pampa vegetation. 

Most deserts and (semi-) arid regions occur between 10° and 35° latitude (e g. Sahara desert, Kalahari desert), in the interior parts of continents (e g. Australia, Gobi desert) and in rain shadow areas in fold belts (e.g. Peru, Nepal). Large parts of the arctic tundra receive less than 250 mm precipitation per annum and qualify as arid regions too (FAO, 2001). 

Polar and subtropical fronts have shifted southwards in the (geologically) recent past and many regions that are arid today once had a more humid climate. Conversely, many of the present humid regions were much drier in glacial periods, especially between 20,000 and 13,000 BP when aeolian processes influenced land formation more than at present. Mass wasting, fluvial processes and aeolian processes are the most important landform-shaping factors in arid and semi-arid regions. 

Fluvial Landforms in Arid and Semi-Arid Regions... 

Most of Australia s arid and semi-arid regions consist of a highly weathered, extremely old land surface. In the western Platform Archaean... 

Total Mo in soils of China varies from 0.1-6 mg/kg with an average of 1.7 mg/kg. Arid and semi-arid soils have 0.2-4.2 mg/kg total Mo. Average Mo contents in arid and semi-arid regions are 1.58 mg/kg. In general, lower Mo contents are found in soils of arid and semi-arid regions than the humid and tropic/subtropic soils. In soils derived on loess, total Mo is from 0.21-1.45 mg/kg with an average of 0.62 mg/kg. Soils in the North... 

Soils around the Pb-Zn Port Pirie smelter in the semi-arid region of South Australia were found to contain 2,220 mg/kg Pb (about 3 km away from the mine) (Cartwright et al., 1976). Lead concentrations decreased to 140 mg/kg at a distance of 16 km and were further reduced to 32 mg/kg at 33.5 km. In tailing piles of the Leadville mining area of Colorado, U.S., Pb concentrations ranged from 6,000-10,000 mg/kg (Brown et al., 1999). XAFS spectroscopy showed that 50% of the total Pb occurred as adsorbed... 

Reduced Cr(III) may be re-oxidized into Cr(VI) by Mn oxides in soils. Chung et al. (2001) reported that native Cr(III) in subsurface materials of arid and semi-arid regions can be oxidized to soluble chromate by native manganese oxides. If subsurface materials contain a low content of Mn oxides, the re-oxidization of reduced Cr(III) is not significant. 

Han F.X., Binding, distribution and transformations of polluting trace elements in soils of arid and semi-arid regions receiving waste inputs. Ph.D. Dissertation, Hebrew University of Jerusalem. 1998. 

Coccidioidomycosis is caused by infection with Coccidioides immitis. The endemic regions encompass the semi-arid regions of the southwestern United States from California to Texas, known as the Lower Sonoran Zone. It encompasses a spectrum of illnesses ranging from primary uncomplicated respiratory tract infection that resolves spontaneously to progressive pulmonary or disseminated infection. 

Allelopathy found hopeful utilization in plant protection against parasite weeds. The main world parasitic species are the witchweeds (Striga spp.), broomrapes (Orobanche spp.), and eventually dodder (Cuscuta spp.). Witchweeds and broom-rapes attack many economically important crops especially throughout the semi-arid regions. Early detection of parasitic weed infestation and protection is difficult because of the growth habit of a root parasite and huge production of dust-like seeds viable up to 20 years (Kebreab and Murdoch 1999). 

Anderson, K.A. and Johnson, E. 2001, Bioavailable organochlorine pesticides in a semi-arid region of Eastern Oregon, USA, as determined by gas chromatography with electron capture detection. J. AOAC 84 1371-1382. 

The results of this work indicate that triangular and hexagonal morphologies are commonly and rapidly formed by evaporation, do not require bacteria, and have similar size distribution as those found naturally near a Au deposit in Western Australia. The inorganic process of groundwater evaporation is potentially the driving force for the formation of transported Au deposits in the vadose zone, particularly in arid and semi-arid regions of the world. 

Alves, R. R. N., Neto, N. A. L., Brooks, S. E., and Albuquerque, U. P. (2009). Commercialization of animal-derived remedies as complementary medicine in the semi-arid region of Northeastern Brazil. J. Ethnopharmacol. 124, 600-608. 

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