Crop Irrigation

AGRICULTURAL CROPS Irrigation water, tolerated level AQUATIC LIFE Freshwater organisms Sensitive species, tolerated level <15,000 pg/L 1... 

Keywords Conventional crop irrigation concerns Halophyte irrigation... 

The yield of a crop irrigated with saline water is related to its salinity tolerance, such that once the threshold of tolerance is exceeded, the yield will decline. The following relationship derived by Mass and Hoffman (1977) shows this decrease in yield as soil salinity exceeds the threshold salinity for a species of plant ... 

Reichardt W, Mascarina GB, Padre B, Doll J. 1996. Microbial communities of continuously cropped, irrigated rice fields. Applied and Environmental Microbiology 63 233-238. 

The volume of water used for crop irrigation is measured in acre-feet, where 1 acre-foot is the amount of water needed to cover 1 acre of land to a depth of 1 ft. 

Armon, R., Dosoretz, C.G., Azov, Y. and Shelef, G. (1994) Residual contamination of crops irrigated with effluent of different qualities a field study. Water Science and Technology 30, 239-248. 

Drinking water is necessary for people, livestock, wildlife, crop irrigation, and for recreation. Although 70% of the Earth s surface is covered with water, most is salt water (salinity of 3.5%) and not fit to drink. Only 3% of the water on the Earth is freshwater (water that contains only minimal quantities of dissolved salts) and much of this water is in snow and ice (e.g., glaciers) as well as lakes, streams and groundwater. In some places in the world, freshwater is plentiful (e.g., the Great Lakes) however, in many places water is scarce. Wars have been fought over freshwater resources. 

The objective of these studies therefore is to assure the continued operation of existing diesel engines, particularly those used in crop irrigation, by converting them to dual-fuel engines with minimum modifications and using producer gas as supplementary fuel. It includes the design of a simple gas producer that can be fabricated inexpensively. 

The question of quantitative restrictions on water consmnption for crop irrigation should be addressed more fully by organic farming. Water is one of the key resource issues for the 21 century and as such requires an appropriate response from the organie movement. In some specific situations, water availability may be absolutely limiting on the total amoimt of farming of any kind that can... 

These soils are droughty as they have a very low available water capacity. For some crops irrigation is required. 

Irrigation is needed on light soils and often with later crops. Irrigation can damage the wax layers on the head increasing the risk of spear rot and should end twenty days before harvest. 

Irrigation is essential in most of the earrot growing regions, particularly on sandy soils and for early crops. Irrigation should be seheduled to avoid wet-diy cycles which can cause root sphts and cracking. 

The economic gain per year from the crops irrigated with seawater, gimg,year, is given by... 

Today, seawater desatinalion is mostly used to produce fresh potable water for human consumption and crop irrigation. Industrial applications of desalinated seawater are... 

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