Efficient Production Mechanism Of Grassland And Technology Of Healthy Breeding Of Cattle And Sheep In The Karst Rocky Desertification

The Karst rocky desertification causes the loss of resources,the adverse ecological environment,the traditional backwardness of grassland development and feeding methods,and the slow development of socio-economic,which is facing difficult conditions of ecology and economic.According to the basic principles of physical geography,agro-environmental sciences,botany,biochemistry,animal nutrition,combined with various theories such as ecological niche,adaptive control and nitrogen metabolism in the rumen,this paper selected Huajiang comprehensive demonstration area with medium-intensive rocky desertification of karst plateau-canyon and the Salaxi comprehensive prevention and control demonstration area with potential-light rocky desertification of karst plateau-mountain of Bijie in Guizhou province,used a variety of research methods like analysis of variance,cluster analysis,correlation analysis,regression analysis and factor analysis,based on the background survey from 2015 to 2016,four representative species that Medicago sativa and Dactylis glomerata were selected for forage modulation experiment in spring of 2017.The seedling preservation experiments were carried out using cover film,straw,etc.Grassland soil fertilization experiments and grassland mowing experiments are aimed at the different grading periods of soil physical and chemical properties in different rocky desertification areas and pastures.The 16 indexes of 88 samples were repeated 2 times,and 2878 data were statistically analyzed,the routine ingredients and the quality evaluation of hay were analyzed,the health feeding evaluation of cattle and sheep was carried out by combing with digestion and metabolism principle of cattle and sheep,which is to provide scientific and technological reference for rocky desertification control and the development of ecological animal husbandry.1.Through different sowing depth and mulching materials to reveal the mechanism of keep a full stand of forage seedlings and find the trench depth,soil cover thickness and mulching method to suit rocky desertification of different grade.In the potential-light rocky desertification area,the sowing depth should be shallow ditches and shallow soil cover,the selection order of mulching mode is the best mulching film,followed by mulching litter,mulching straw and no mulch.In the moderate-intense rocky desertification area,the sowing depth should be shallow ditches and shallow soil cover,the selection order of mulching mode is the best mulching film,followed by mulching straw,mulching litter and no mulch.2.According to the soil nutrients and available soil holding capacity for grassland under different grades of rocky desertification environment,combining with the nutrient requirements of forage and utilization rate of fertilizer,soil testing and formula fertilization can increase pasture production and save fertilizer and cost.In the moderate-intense rocky desertification area,comparing with conventional fertilization,the forage yield of Medicago sativa was increased by 24.3% and 35.6%,respectively,and increased by 85.4% and 68.4% compared with the control group.In the potential-light rocky desertification area,the forage yield of Dactylis glomerata L.was increased by 23.3% and 74.7%,respectively,and increased by 73.4% and 108.8% compared with the control group.3.The mechanism of the mowing period for Medicago sativa L.and Dactylis glomerata.in different phenological periods is affected by the double dynamics of pasture production and nutrient accumulation.Medicago sativa L.had the best mowing at the early flowering stage.Although the plant height,stem-leaf ratio and forage yield were higher in Medicago sativa,the crude protein content decreased and the feeding value was low.Dactylis glomerata should be mowed from heading stage to flowering stage,and its plant height,tiller number of per plant,yield and feed value is high,and the crude protein content can reach 20 or more.4.Through the metabolism of carbohydrates,crude protein and crude fat by cattle and sheep,according to the nutritional composition of forage grasses at different cutting times,it was concluded that the relative feeding value of Medicago sativa at the early flowering stage was the highest,reaching 175.97.Castration at this time,rich in crude protein content.The relative feeding value of Dactylis at the jointing stage was the highest,reaching 104.81.The dry matter digestibility of cattle and sheep in the jointing stage was much higher than that in the heading stage and flowering stage.5.Integrating the technology system of high-efficient production of grassland and healthy breeding of cattle and sheep in rocky desertification area.The high yield mechanism of grassland fertilization was integrated the key technology of grassland formula fertilization,the film mulching technology suitable for rocky desertification area was extracted from the mechanism of keep a full stand of grass seedlings with different mulching methods,and then all the techniques were integrated to form the technology system of high-efficient grassland production and healthy breeding of cattle and sheep in the karst rocky desertification environment.