Search results
Results From The WOW.Com Content Network
Deficit irrigation (DI) is a watering strategy that can be applied by different types of irrigation application methods. The correct application of DI requires thorough understanding of the yield response to water (crop sensitivity to drought stress) and of the economic impact of reductions in harvest. [1]
Scholars Mt. Pleasant and Burt reproduced Iroquois methods of cultivation with Iroquoian varieties of maize at several locations in New York. They reported maize yields of 22 to 76 bushels per acre (1.4 to 4.8 tonnes per hectare). Soil fertility and weather were the main determinants of yield. [14] Mt.
Field Water Efficiency (%) = (Water Transpired by Crop ÷ Water Applied to Field) x 100; Increased irrigation efficiency has a number of positive outcomes for the farmer, the community and the wider environment. Low application efficiency infers that the amount of water applied to the field is in excess of the crop or field requirements.
Water stress is the most ubiquitous stress factor, often denoted as K w. Stress coefficients tend to be functions ranging between 0 and 1. The simplest are linear, but thresholds are appropriate for some toxicity responses. Crop coefficients can exceed 1 when the crop evapotranspiration exceeds that of RET.
In one example, a ten-year experiment in Malawi showed that, by using the fertilizer tree Gliricidia (G. sepium) on land on which no mineral fertilizer was applied, maize/corn yields averaged 3.3 metric tons per hectare (1.5 short ton/acre) as compared to 1 metric ton per hectare (0.45 short ton/acre) in plots without fertilizer trees or ...
Irrigation schemes in the world use about 3 500 km 3 water per year, of which 74% is evaporated by the crops. [7] This is some 80% of all water used by mankind (4 400 km 3 per year). The water used for irrigation is roughly 25% of the annually available water resources (14 000 km 3) and 9% of all annual river discharges in the hydrological cycle.
A maize crop yielding 6–9 tonnes of grain per hectare (2.5 acres) requires 31–50 kilograms (68–110 lb) of phosphate fertilizer to be applied; soybean crops require about half, 20–25 kg per hectare. [21] Yara International is the world's largest producer of nitrogen-based fertilizers. [22]
In an opportunity cropping system, crops are grown when soil water is adequate and there is a reliable sowing window. This form of cropping system is likely to produce better soil cover than a rigid crop rotation because crops are only sown under optimal conditions, whereas rigid systems are not necessarily sown in the best conditions available.