灌溉排水系统工程

The field experiments were carried out in 2007 and 2008 to study the effects and strategies of drip irrigation with saline water for oleic sunflower. Five treatments of irrigation water with average salinity levels of 1.6, 3.9, 6.3, 8.6, and 10.9 dS/m were designed. For each treatment, 7 mm water was applied when the soil matric potential (SMP) 0.2 m directly underneath the drip emitters was below 20 kPa, except during the seedling stage. To ensure the seedling survival, 28 mm water was applied after sowing during the seedling stage. Results indicate that amount of applied water decreases as salinity level of irrigation water increases. The emergence will be delayed when the salinity level of irrigation water is higher than 6.3 dS/m, but these differences will be alleviated if there is rainfall during emergence period. The final emergence percentage is not changed when salinity level of irrigation is less than 6.3 dS/m, and the percentage decreases by 2.0% for every 1 dS/m increase when the salinity level of irrigation water is above 6.3 dS/m, but the decreasing rate will be reduced if there is rainfall. The plant height and yield decrease with the increase of salinity of irrigation water. The height of plants decreases by 0.6–1.0% for every 1 dS/m increase in salinity level of irrigation water.

Limitations on soil water supply can decisively diminish crop yields by influencing the development and advancement of plants. Thus, screening apparatuses that can recognize crop water pressure early have been for some time explored, with covering temperature (CT) being generally utilized for this reason. In this review, we researched the connection between covering temperature recovered from automate delevated vehicles (UAV) based warm symbolism with soil and plant credits, utilizing a rain fed maize field as the area of study. The flight mission was led during the late vegetative stage and at sun oriented early afternoon, when an impressive soil water deficiency was recognized by the dirt water balance model utilized. While the pictures were being taken, soil testing was directed to decide the soil water content across the field. The examining results exhibited the spatial inconstancy of soil water status, with soil volumetric water content (SVWC) introducing 10.4% of variety and values near the super durable shrivelling point (PWP), reflecting CT readings that went from 32.8 to 40.6 _C among the testing areas.