Evaluation Of The Benefits Of Jujube Grass Intercropping In The Arid And Sandy Areas Of Southern Xinjiang

Large areas of dwarf,open-sided jujube trees are planted in Hotan,an arid and sandy region in southern Xinjiang.The wide row cultivation method and drip irrigation water conservation technology provide good space and irrigation conditions for intercropping,and three controls were established by setting up different intercropping herbaceous plants(total10 economic,green manure or fodder plants)in local jujube orchards,and considering the local traditional management mode of clear plowing and the influence of intercropping water and fertilizer supply: clear plowing + basal fertilizer application + irrigation,clear plowing +basal fertilizer application and clear plowing,etc.Three controls were established: clear tillage + basal fertilizer + irrigation,clear tillage + basal fertilizer and clear tillage.We measured the microclimate,growth of jujube trees,soil nutrients,salinity and alkalinity,and the output of trees and products under intercropping at different growth periods of jujube trees and intercropping plants,and compared the advantages and disadvantages of different intercropping plants and their applications in terms of improving the microclimate,improving the soil and increasing the output of jujube plantations.value.The following main results were obtained:(1)Melilotus officinalis(L.)Pall could be the best intercropping grass to improve the microclimate of jujube orchards in the arid and sandy areas of southern Xinjiang,which significantly reduced the daily difference of air temperature by 1.43℃,the ratio of the highest daily air relative humidity to the lowest humidity value by 37.6%,the daily difference of surface temperature by 4.21℃,and the water content of soil 0-20 cm by 0.46%compared with the clear-cut control,followed by Medicago sativa L..While Zea mays L.,Brassica rapa var.oleifera,Cyperus esculentus var.sativus,Phleum pratense L.and Sorghum bicolor × sudanense were not conducive to the improvement of jujube garden microclimate compared to the clear-cut control.(2)Medicago sativa L.had the best effect in improving soil nutrients and salinity in arid and sandy areas of southern Xinjiang,with an increase of 12.16% in total phosphorus,0.25%in total potassium,1.52% in ammonium nitrogen,63.41% in nitrate nitrogen,0.78% in p H,43.11% in fast-acting phosphorus,6.04% in fast-acting potassium,and 15.36% in organic matter compared with the clear-cut control.The organic matter increased by 15.36%,followed by Cyperus esculentus var.sativus.Amaranthus caudatus L.had no significant effect compared with the clear-cut control,while Zea mays L.,Brassica rapa var.oleifera,Sorghum bicolor × sudanense,Sophora alopecuroides L.,Arachis hypogaea L.,Phleum pratense L.and Melilotus officinalis(L.)Pall increased the consumption of soil nutrients and secondary salinization of the soil.(3)The stand and product output benefits of Sorghum bicolor × sudanense were the best,with a significant 62.46% increase in fruit set rate,6.36% increase in date production value,4.04% increase in total fruit sugar content,and 43.49% increase in total profit in the first year of cultivation compared to the clear-cut control,followed by Phleum pratense L..Medicago sativa L.,Zea mays L.,Brassica rapa var.oleifera,Sophora alopecuroides L.,Arachis hypogaea L.,Cyperus esculentus var.sativus and Amaranthus caudatus L.all showed some improvement over the clear-cut control,while Melilotus officinalis(L.)Pall had essentially no effect on output.(4)When all three benefits were evaluated,intercropping Medicago sativa L.was the best in jujube orchards in the arid and sandy areas of southern Xinjiang.