The Response Of Alfalfa To Fertilization In East Of Yellow River In Ningxia

At present,desertification in East of Yellow River in Ningxia is still very serious with overgrazing existing.The production of forage cannot meet the needs of local animal husbandry development.Alfalfa is a kind of perennial quality forage and it has strong adaptability to the environment.Alfalfa cultivation can effectively improve soil and soil fertility while providing feed for livestock.With the development of animal husbandry,the demand for alfalfa continues to increase,and fertilization has become an effective way to increase the production of alfalfa.However,current research on alfalfa fertilization is not yet mature.In this study,we conducted a fertilization experiment on alfalfa in East of Yellow River in Ningxia to explore the effects of different amounts of nitrogen fertilizer,compound fertilizer and Kelp Bio-organic Fertilizer on the growth of alfalfa in East of Yellow River in Ningxia and the role it plays in improving soil fertility in desertification areas.We aim to explore the best fertilization types and fertilizer amounts on alfalfa,providing basis for the scientific fertilization of alfalfa and exploring new ways of reforestation in desertification areas.The main findings are as follows:(1)Applying nitrogen fertilizer can significantly improve the plant height and biomass.To a certain extent it can promote chlorophyll generation and improve net photosynthetic rate of alfalfa leaves.However,excessive nitrogen fertilizer can inhibit the branches of alfalfa,reducing its fresh-dry ratio and affecting its quality.It can also reduce the contents of available P,available potassium and soil organic matter.Inappropriate fertilization will do some damage to the soil.The optimal amount of nitrogen fertilizer for alfalfa in East of Yellow River in Ningxia is 120kg/hm2.(2)Applying compound fertilizer can significantly increase the content of available P in the soil,increasing soil organic matter to a certain extent and increasing soil fertility.It will effectively increase the yield of alfalfa by promoting more branches of alfalfa.At the same time,the application of compound fertilizer can significantly increase the chlorophyll content and increase the net photosynthetic rate of alfalfa leaves.However,it has no significant effect on the quality of alfalfa.The optimal amount of compound fertilizer for alfalfa in East of Yellow River in Ningxia is 180kg/hm2.(3)The Kelp Bio-organic Fertilizer had the best comprehensive effect on alfalfa,and was superior to nitrogen fertilizer and compound fertilizer in terms of increasing alfalfa plant height,the branches of alfalfa,net photosynthetic rate of alfalfa leaves,and the yield of alfalfa.Kelp Bio-organic Fertilizer can improve the fresh-dry ratio of alfalfa to a certain extent and improve its quality.Application of Kelp Bio-organic Fertilizer can also significantly increase the content of soil organic matter and improve soil fertility.The optimal amount of Kelp Bio-organic Fertilizer for alfalfa in East of Yellow River in Ningxia is 480 kg/hm2,two times in the same doses were applied to the field.The first fertilization was performed during the return to the young stage(April 15th).The second fertilization was performed after the first castration(June 15).