Experimental Research On Rainwater Use Efficiency Enhancement Of Typical Terraced Orchard In Loess Hilly Region

With the growing shortage of the world within the scope of drought and water resources,development and utilization of water resources has become a new way to solve the water shortage crisis in countries and regions with the growing shortage of water resources around the world.China is one of 13 deprivation country that per capita water resources is 2220m~3 less than 1/4 in the world average level.Water resources was shortage in the Loess Plateau,many areas per capita water resources was less than 500m~3,the water of agricultural irrigation was very tense.in 21 th century,in order to solve the Loess Plateau hilly apple orchard yield and quality,developed the terraced orchard irrigation techniques from the rain,the Loess Plateau Mountain Apple development made great progress.However,after nearly 20 years of rain collecting irrigation of fruit industry development,made significant achievements,based on the restrict by existing rural productivity level,appropriate conservation irrigation need to further development,storage facilities need to be research and develop for further research,the coupling of water and fertilizer of conservation irrigation system needs to be improved and so on.This research is based on develop fruit production technology used rain irrigation in Yanan Ansai Tower Hill orchard from 2000.Through the field of water and fertilizer coupling experiment,the author found that:(1)Water deficit in loess hilly area of terraced orchards flat water with different growth period of fruit has a certain amount of the irrigation can improve the ratio of utilization of water in arid years.The farmers do not pay attention to the rainwater irrigation in Mountain fruit Orchard,the water and fertilizer coupling experiment,showed that the water demands and rainfall was basic same,but the lack of water was obviously.fruit water demans every month were 53.10 mm,92.07 mm,133.80 mm,119.73 mm,106.64 mm,81.60 mm,24.18 mmin month 4-10 in median water year.as a benchmark,natural rainfall recharge about 47% trees in dry year(2015),about 78% trees in flat year(2016 years and the average case),,annual water supply for a certain amount of peace in dry years;reasonable irrigation can improve the utilization efficiency of orchard water per plant increased production of 19.7%~29.7%;The yield of single plant increased with irrigation amount,the yield of supplementary irrigation decreased with the increase of irrigation appropriate for irrigation,saving water efficient production was important in orchard management.(2)Soil moisture decreases with increasing elevation in typical terraced orchard in the loess hilly region,nutrient showed fluctuat with elevation rising.Experimental results showed that the Tower Hill orchard in the range of 1100m~1300m,every 10 m increase of elevation,soil moisture content reduced about 0.64% in 0~200cm,root soil moisture was reduced by about 0.68%.Soil nutrients content increased with elevation Organic matter,total phosphorus,total nitrogen content showed a trend of increasing volatility,total potassium content showed a decreasing trend of volatility(3)The field test showed that during the whole growth period of fruit in the median water year(2016),the test range of optimal irrigation fertilizer management: irrigated 3 times during the growth of apple trees were,winter+ the first fruit growth period+ second fruit growth period,to pay 80% of field capacity,respectively,and in each irrigation water with phosphorus potassium compound fertilizer 1kg/ plant,“yield and yield+ Satisfaction” was the best.irrigation management needs to be further testing or model optimization druing drought and wet years.(4)Further analysisthe test data of fruit production in different areas in Loess Plateau showed that the elevation optimal range of 1100m~1500m was best for planting the red Fuji Apple in Loess Hilly and gully region of.single fruit weight and fruit diameter increase with elevation from 800 m to 1400 m decreased with the elevation from 1400 m to 2000m;the fruit hardness increases in the range of 800m~2000m with the increase of altitude;the soluble solids in elevation of about 1500 m is the highest,the fruit shape index with the elevation increased,the ratio of sugar and acid in 1100m~2000m reduced with the elevation increased.orchard in the elevation range of 1100m~1500m,had the largest rate of large red apple;fruit firmness between 7.25~9.52gkf/cm2;the soluble solids content of the fruit shape index 13.2~14.81%;Fruit shape index was 0.81~0.93;the ratio of sugar and acid >40 concentration distribution area.