Effects Of Two Utilization Ways On The Forage Yield And Quality Of Sown Pastures In The Loess Plateau

In this study,we investigated the response of forage yield and forage quality of two pasture utilization methods(simulated grazing vs hay making)on the Loess Plateau.There were seven treatments.We tested five types of forage crops,Medicagao sativa,Sorghumand Vicia,Vicia sativa,Avena sativa and Secale cereal(Rye).We also,tested two mixed crops;Sorghumand Vicia with Vicia sativa and Vicia sativa,Avena sativa.We found:1.In general,simulated grazing increased or maintained greater forage production and forage quality compared to hay making.There were significant differences in forage production between two methods for all the crops except Medicagao sativa.The Crude protein,EE and Ash levels of all forage species were significantly higher in simulated grazing compared to making hay.In contrast,NDF and ADF levels were significantly lower than hay making.2.The forage yield and nutrient quality of the mixed planting by Sorghum Vicia and Vicia sativa were lower than that of mono crop planting,but forage yield and nutrient quality of the mixed crop with Avena sativa and Vicia sativa were higher than that of the mono crop planting.This result is indicating that Avena sativa may be better suited than Sorghum to mixed crop with Vicia sativa.3.We used structural equation model to predict relationships of climatic factors and forage yield and quality.We found that the forage yield and quality was positively related and the annual mean precipitation was the key determinant.4.We fitted a model to predict forage yield(X)from nutrient content(Y)under two pasture utilization methods.All the models were validated linear fitting analysis,contrasting equation and the difference of slope difference between Y = X.We found that the model predictions for NDF for Medicagao sativa,NDF for Avena sativa,NDF and ADF of the rye and the EE,ADF and ASH for the Sorghum for forage yield under the simulated grazing.We also can predicted CP,ADF and ASH of Medicagao sativa,the CP,ASH of Vicia sativa,the CP,EE,ADF,NDF,ASH of Avena sativa,the CP,EE of Rye,the CP,ADF of Sorghum under the making hay.This study clarified the cultivated land use pattern and planting method which is suitable the Loess Plateau.