Study On Production Performance And Soil Nutrient Characteristics Of Soybean Grass Mixed Grassland With Different Planting Modes

Soybean grass mixed sowing can not only improve the crude protein content of Gramineae and enhance the sustainable utilization of grassland,but also has the advantages of fertility.Horqin sandy land is one of the typical sandy soil in China.Therefore,how to improve the yield and quality of forage and improve soil fertility has become a research hotspot.Therefore,alfalfa and Bromus inermis were selected as mixed sowing grass species in this paper.Two factor field experiment was adopted.The planting method was set as the first factor,including peer mixed sowing,cross mixed sowing and inter row mixed sowing;The second factor was the sowing proportion of grass and beans,which were B1:1:1,B2:3:2,B3:2:1,B4:5:2 and B5:3:1 respectively;Taking single alfalfa CKD（0:1）and single Bromus inermis CKH（1:0）as the control,the effects of Mixed Sowing on grassland production performance,nutritional quality and soil physical and chemical properties were discussed,so as to provide a scientific theoretical basis for grass mixed sowing in Horqin sandy land.The results showed that:1.The mixed sowing mode had no significant effect on the total yield of alfalfa,Alfalfa+Bromus inermis（P>0.05）,but had a very significant difference on the total yield of Bromus inermis（P<0.01）;The mixed sowing ratio had no significant difference on the total yield of alfalfa and Bromus inermis（P>0.05）,but had a very significant difference on the total yield of Alfalfa+Bromus inermis（P<0.01）;Under the interaction of mixed sowing mode and mixed sowing proportion,the total yield of alfalfa,Bromus inermis and Alfalfa+Bromus inermis had a very significant difference（P<0.01）.The yield of Bromus inermis in the mixed sowing mode was lower than that in the cross and inter row mixed sowing modes;The yield of alfalfa and the total yield of forage reached the maximum,which were 11.26 t·hm^-2and 13.55 t·hm^-2respectively;The yield of Bromus inermis was higher under the treatment of inter row mixed sowing（3∶1）.2.The mixed sowing method had a very significant correlation with the content of nitrogen and phosphorus in the first and third crops of Alfalfa（P<0.01）,the content of carbon,nitrogen and phosphorus in the second and third crops of Alfalfa（P<0.05）,the content of phosphorus in the second and third crops of Bromus inermis（P<0.01）,and the content of C in Bromus inermis（P<0.05）;The mixed sowing ratio had significant correlation with the content of nitrogen,carbon and phosphorus in the first and second crops of Alfalfa（P<0.05）,the content of nitrogen,carbon and phosphorus in the third crop of Alfalfa（P<0.01）,and the content of nitrogen,phosphorus and carbon in the first and second crops of bromegrass（P<0.01）;Under the interaction of mixed sowing mode and proportion,there was a very significant correlation between the second and third nitrogen content of alfalfa,the phosphorus content of the first and third stubbles,and the carbon content of the first and second stubbles（P<0.01）,and there was a significant difference between the three stubbles of Alfalfa（P<0.05）.Under the interaction of mixed sowing mode and proportion,there was a very significant correlation between the nitrogen and phosphorus of each stubble of awnless Finch and the carbon of the first and second stubbles（P<0.01）.3.The mixed sowing mode had no significant effect on forage acid detergent fiber,neutral detergent fiber and relative feed value（P>0.05）,had a significant effect on the crude protein of the first crop of Alfalfa（P<0.05）,had a very significant difference on the crude protein of the second crop of Alfalfa（P<0.01）,and the mixed sowing proportion had a very significant difference on the crude protein of each crop of Bromus inermis（P<0.01）;The mixed sowing proportion had a significant effect on the neutral detergent fiber of Alfalfa in the second and third stubbles（P<0.05）,and on the acid detergent fiber of Alfalfa in the third stubble（P<0.05）.The mixed sowing mode and proportion could effectively improve the crude protein content of forage,and had a significant effect on the relative feeding value of Alfalfa（P<0.05）.The Forage Value of the two forages decreased gradually with the increase of grass in the mixed sowing proportion.4.There was a significant correlation between mixed sowing and soil carbon content in 0-10cm（P<0.01）;The effect of mixed sowing ratio on soil carbon was significant（P<0.05）;Under the interaction of mixed sowing mode and proportion,there was a significant correlation between the contents of nitrogen,phosphorus and carbon in0-10cm soil（P<0.01）.There was significant difference in carbon content of soil10-20cm by mixed sowing method（P<0.05）;The mixed sowing proportion had no significant difference on the content of nitrogen,phosphorus and carbon in 10-20cm soil（P>0.05）.Under the interaction of mixed sowing mode and proportion,there was significant difference on the content of phosphorus in 10-20cm soil（P<0.05）;The mixed sowing method had no significant difference on the content of nitrogen,phosphorus and carbon in soil 20-30cm（P>0.05）,and the mixed sowing proportion and the interaction of mixed sowing method and proportion had no significant difference on the content of nitrogen,phosphorus and carbon in soil 20-30cm（P>0.05）.5.Compared with single alfalfa and Bromus inermis,the soil urease activity of peer mixed sowing and inter row mixed sowing decreased,and there was no significant difference compared with single alfalfa and Bromus inermis（P>0.05）.Under the ratio of 3∶2,cross sowing increased the urease activity of 0-10cm soil,which was significantly higher than that of other proportions（P<0.05）;The effect of Mixed Sowing on catalase in soil 0-10cm was significant（P<0.05）.