| In this thesis,the water-saving irrigation demonstration area of Wuhai Plantation was investigated,the threshold of irrigation was determined and the benefit was evaluated.The main findings are as follows.1.The soil types of the plantation demonstration land are Aeolian Sandy soil and river sandy soil,and the roots of the main tree species are concentrated in 0 ～ 50 cm soil layer.2.According to the field water holding capacity and the law of Water Movement,the start-up thresholds of Aeolian sand soil and river sand soil irrigation are 5.64%and 8.32% respectively,and the single effective irrigation time is 8 h and 6 H respectively.3.In the past 2 years,the average water-saving benefit of the water-saving irrigation system was 137560.25 yuan.The cost-benefit ratio is 1.12 when used for 5years,which can recover the project input cost and start to gain economic benefit.The benefit is doubled when used for 9 years is 1.99.4.The annual growth of tree height and dbh increased by at least 4.36% and108.33% respectively,and the annual growth of SHRUB crown increased by at least38.10%,the social satisfaction of water-saving irrigation system in plantation demonstration land is 100% as a whole,but the satisfaction ratio of different investigation contents is different. |
