water and nitrogen fertilizer are two main factors of agricultural production and deficiency of each one makes reduction in the yield. deficit irrigation is one of the ways for water management in arid and semiarid areas, but it is effective on the need of nitrogen. excessive use of nitrogen will be a waste of capital and environmental pollution. in this study the interaction of water and nitro...

We examined resource limitations on growth and carbon allocation in a fast-growing, clonal plantation of Eucalyptus grandis urophylla in Brazil by characterizing responses to annual rainfall, and response to irrigation and fertililization for 2 years. Productivity measures included gross primary production (GPP), total belowground carbon allocation (TBCA), bole growth, and net ecosystem product...

abstract one of the ways to increase economic and environmental efficiency of drainage systems is water table management. water table management consists of, controlled drainage and subirrigation. this study examines the effect of controlled drainage on yield, root distribution pattern and water use efficiency of maize (sc 704) in karaj. the experiment was performed as a randomized complete des...

soilless culture of greenhouse vegetables has been a fast developing section in iran during recent years. most growers fertigate plants without enough knowledge about plant water requirements. since some soilless substrates have low water retention capacity, wasting a great amount of nutrient solution can be occurred due to poor management. in this research work, effects of hydro gel amendment ...

experiments were conducted in 1998 and 1999 to study the effects of different levels of potassium and irrigation intervals on yield and water use efficiency of two genotypes of sugar beet (a37.1 and 12681) in khorasan agricultural research center (torogh, iran). potassium levels were; no potassium application, increasing potassium to 5% of soil cation exchange capacity (cec) and second treatmen...

introduction: designing and management of sprinkler irrigation systems depend on the situation and location of its implementation and often rely on professional and long-term tests (9). having a good irrigation system depends on knowledge of the relationship between soil, water, plants, irrigation scheduling, the required amount of irrigation water to the water-holding capacity of soil, climate...

evaluating the performance of irrigation systems by providing the possibility of increasing irrigation efficiency in those systems is an important factor in the field of water resources management. in this study, the performance of three systems were evaluated, including linear move sprinkler irrigation systems in maize, sugar beet and alfalfa fields of magsal agro-industrial company which is l...

effect of different irrigation regimes and nitrogen fertilizer on percentage of grain fatty acids, yield, water and nitrogen use efficiency of pumpkin was studies as split plot based on complete randomized block design with three replications in growing season of 2013. irrigation treatments (320, 420, 600 and 900 mm ha-1) were se as main plots and nitrogen fertilizer (0, 130, 260, 390 and 520 k...

Empirical studies suggest that cost-share programs are unlikely to reduce exploitation of ground water and nonpoint-source pollution. By introducing an induced irrigation technology in our model, we find theoretically that the optimal amount of irrigation water and nitrogen fertilizer increases (decreases) when the increased rate of the marginal net economic benefits from their use with an indu...

Potato grown for early or off-season production plays a crucial role in the economy of several areas in the Mediterranean countries. Irrigation is important for determining yield and earliness, thus a better investigation of plant response under various pedo-climatic conditions can help to improve resource use efficiency and farmer income. A two-year field research (2009-2010) was carried o...