Effect of water harvesting techniques on vegetation characteristics (natural and planted), runoff and sedimentation at semi-arid area

Abstract

Abstract

Agriculture production in Palestine depends on rainfall which is highly variable spatially and temporally. Water is the key environmental factor that determines plant growth at the Eastern slopes, and because of the characteristics of rainfall, in general, and low precipitation in particular the productivity of plants is very low (MOA, 2012). Therefore, this study was conducted at Al-Ubeidiya in Bethlehem governorate to evaluate the effect of using water harvesting techniques on the productivity of barley and natural vegetation through its influence on runoff and soil sedimentation during 2013, 2014 and 2015. Split plot design was used to compare between treatments. the results showed the positive effects of water harvesting practices on barley productivity where the spike and straw weight increased significantly compared with the conventional cultivation, spike, straw weights and plant height gave the best results in strip planting followed by P-S-P then the contour ridges while the lowest values were in the traditional planting (S-P). In natural vegetation study, surface runoff was decreased significantly by 49.5% and 45.4% in gentle slope (10%) by using contour ridges at 3m and 5m distances, respectively, compared with control area, as well as water runoff in steep slope (20%) reduced by 43.6% and 32.2% in contour ridges at 3m and 5m distances. Also the data showed the positive effects of contour ridges at 3m and 5m distances in the two slopes (gentle 10% and steep 20%) on natural vegetation characteristics. Results showed that plant biomass was recorded the highest values in area treated by contour ridges at 5m distance in gentle and steep slopes, it was 203.4kg/dunum and 174.8 kg/dunum, respectively, and it was significantly increased by 158.9 kg/dunum and 113.1kg/dunum in area treated with contour ridges at 3m distance in gentle and steep slopes respectively. In addition plant density increased significantly in contour ridges with 3 m and 5 m distances in gentle slope were it recorded the highest plant density (49.4 plants/0.25m2 and 52.7 plants/0.25m2, respectively) compared with the other treatments. In addition plant cover result showed no significantly difference between all treatments. Using simple way to enhance field crops production and improve rangeland performance is possible, but it needs previous planning and period of time to see the positive effects on the land.