degraded soils in northwest china are mostly nonproductive due to imbalanced nutrient and inadequate water supply. the effects of manure application at three different rates (7.5, 15.0, and 22.5 t ha–1) combined with chemical fertilizers on soil water and water-use efficiency in maize [compared with chemical fertilizers (control)], under semi-arid conditions in dark loessial soil and over a per...

in order to improve irrigation water productivity (wp) at rice production, a field experiment was conducted at shahid fozveh research station (esfahan region) during 2001-2003. experiment was arranged in a split plot design (rcbd) with three replications. the treatments were: three levels of irrigation managements including i1: permanent flooding under 3.5cm water during growth period, i2:perma...

Stomatal conductance links plant water use and carbon uptake, and is a critical process for the land surface component of climate models. However, stomatal conductance schemes commonly assume that all vegetation with the same photosynthetic pathway use identical plant water use strategies whereas observations indicate otherwise. Here, we implement a new stomatal scheme derived from optimal stom...

in this research, some of the echo-physiological characteristics of pistachio trees were studied to understand crop response to drought stress and determine the best irrigation interval. this experiment was carried out in an orchard with a sandy loam textured soil and a commercial cultivar of pistachio named ouhadi grafted on pistacia vera l. rootstock for three years. the irrigation system sel...

abstract- maize production, which is ranked after wheat and barely in fars province, iran, needs a considerable amount of irrigation water that is not available in scarce water conditions in drought situations. therefore, proper planting method can improve irrigation water management. the objectives of the present study were to investigate the effects of two planting methods, on-bed and in furr...

By use of a common primary-production model and identical photosynthetic parameters, four different methods were used to calculate quanta (Q) and primary production (P) at depth for a study of high-latitude North Atlantic waters. The differences among the four methods relate to the use of pigment information in the upper water column. Methods 1 and 2 use pigment biomass (B) as an input and a su...

The growing scarcity of water resources worldwide is conditioned not only by precipitation changes but also by changes to water use patterns; the latter is driven by social contexts such as capital intensity, trade openness, and income. This study explores the determinants of water use by focusing on the effect of trade openness on the degree to which water is withdrawn and consumed. Previous s...