The organophosphate (OP) insecticides diazinon and chlorpyrifos have been frequently detected in the San Joaquin River, California, USA. Irrigation tail waters are a significant source of OP pesticides in the watershed. This study tested several management practices for reducing offsite movement of chlorpyrifos to surface water from flood irrigated alfalfa. Management practices evaluated includ...

the manning roughness coefficient is an important parameter in the design and evaluation of furrow irrigation. despite its importance, estimation of this parameter for surface irrigation is very difficult, particularly in furrow irrigation. in this study, an evalue model was used to estimate the manning roughness coefficient in furrow irrigation. the model was based on volume balance and develo...

to better understand the potential for improving biomass accumulation and radiation use efficiency (rUE) of winter wheat under deficit irrigation regimes, in 2006–2007 and 2007–2008, an experiment was conducted at the luancheng Experimental Station of Chinese academy of Science to study the effects of deficit irrigation regimes on the photosynthetic active radiation (Par), biomass accumulation,...

ِdfferent drip (surface and subsurface) and furrow irrigation methods effects on grain, oil and water use efficiency based on grain black cumin(nigella sativa l.) as medicinal plants was investigated. for this purpose, experiment over the past two years (2009 and 2010) in a randomized complete block was designed in three replications. treatments in this research were consisting of 50, 75 and 100...

Water deficit is one of the most important difficulties, in which happes in dry zone and half dry zones.Water deficit, as the determinative factor, determinates the growing and extension of the plant cover inthese areas. Using the supper attractive, may reduce the production in the crops and control the plantcover in face of dry stress and water deficit. In this paper, the effect of supper attr...

[1] Agricultural water use accounts for around 70% of the total water that is withdrawn from surface water and groundwater. We use a new, gridded, global-scale water balance model to estimate interannual variability in global irrigation water demand arising from climate data sets and uncertainties arising from agricultural and climate data sets. We used contemporary maps of irrigation and crop ...

Sub-surface irrigation (SUI) is a new water-saving irrigation technology. To explore the influence of SUI on soil conditions in a cherry orchard and its water-saving efficiency, experiments were conducted from 2009 to 2010 using both SUI and flood irrigation (FLI) and different SUI quotas in hilly semi-arid area of northern China. The results demonstrated the following: 1) The bulk density of t...

daho has approximately 4 million acres of irrigated agricultural land. Most of it is in pasture and hay crops, grain crops, potatoes, and sugar beets, in hierarchical order. Table 1 shows the number of irrigated acres in the state by crop for 1994. Nearly all of this land is irrigated by either sprinklers (59 percent) or surface irrigation systems (40 percent), with only a very small amount (le...

The appraisal of crop water requirements (CWR) is crucial for the management of water resources, especially in arid and semi-arid regions where irrigation represents the largest consumer of water, such as the Doukkala area, western Morocco. Simple and (semi) empirical approaches have been applied to estimate CWR: the first one is called Kc-NDVI method, based on the correlation between the Norma...