Study on Mode and Technology of Grassland Establishment and Ecological Animal Husbandry in the Karst Rocky Desertification Area
Author:Chi Yong Kuan
Supervisor:xiong kang ning shen xiao yun
South China karst is one of the three karst concentrated contiguous regions in the world.It has the characteristics of wide distribution area,many types of landforms and complete development sequences,which is rare in the world.Rocky desertification is the most serious and typical ecological environment problem in the region,which seriously threatens the ecological security and socio-economic sustainable development of the eight provinces in southern of China.The grass and livestock project is an important part of the comprehensive control project for rocky desertification,it is an important measure to quickly repair the damaged ecological environment and develop the economy in the karst rocky desertification areas.Furthermore,it is of great significance to promote ecological reconstruction and economic development in karst rocky desertification areas.Based on the systematic theories and multivariate multi-scale analysis principle of geography,karstology,ecology,grassology,animal husbandry,according to the key scientific and technological problems about grassland establishment and ecological animal husbandry to be solved in the rocky desertification area,this paper takes the demonstration zone of the medium-intensive rocky desertification comprehensive control zone in the Guanling-Zhenfeng of karst plateau-gorge in Huajiang and the potential-light rocky desertification comprehensive control in the Salaxi of karst plateau-mountain in Bijie as the core research and demonstration zone from 2012 to 2019.Through comprehensive use of field test and monitoring,laboratory analysis,comparative analysis,mathematical statistics and geographic information system research methods and other systematic research techniques,it was systematically studied the mechanism of high-efficiency planting and optimization for grassland and the mechanism of healthy breeding and strategy for ecological animal husbandry in the rocky desertification area.On this basis,the research of model construction,technology research and development,demonstration verification and transfer promotion was carried out in order to provide scientific and technological support and reference for rocky desertification control and economic industry development.The specific research contents and conclusions are as follows:(1)High efficiency establishment and optimization of grassland in the karst rocky desertification areaComparative analysis of grass emergence test by compacted soil,mulching film,shredded grass mulching and different cover soil level was carried out.The results showed that four grasses such as alfalfa has the earliest emergence,the highest emergence rate and the most stable variation coefficient and in the medium cover soil and mulching treatment,followed by the treatment of compacted soil and shredded grass mulching,and the worst performance was no control.The emergence time of grass increases with increasing cover soil thickness,moderate cover soil and mulching film had the best effect on water conservation and soil moisture preservation,it was one of the best methods for pasture planting.Through monitoring recovery effects of the soil physical and chemical properties of 15 kinds of forest-grassland configuration patterns in different rocky desertification grades such as“pepper and alfalfa”and“prickly pear+perennial ryegrass”,the results showed that:the allocation of forest-grassland has an improvement effect on soil physical and chemical properties in rocky desertification area,with the increase of years,the improvement effect of different allocation modes was also different,but the overall situation tended to be good.The improvement situation of soil quality in the moderate-intensive rocky demonstration area is better than that in the potential-middle rocky demonstration area.The soil physical properties of the forest-grassland allocation patterns in the two demonstration areas were basically better than those in the pure forest land,and the chemical properties were not obvious.The soil nutrient index of 15 forest-grassland patterns modes in the two experimental areas was lower than the standard value,and it was necessary to supplement the lack of nutrients.Through the fertilization improvement experiment on the degraded grassland such as alfalfa,the results showed that:the soil physical and chemical properties of three degraded grassland types were significantly different after mowing and fertilization(except for the control group).The physical properties of the improved soil were significantly increased(P<0.05)in soil water content,field capacity,capillary capacity,total porosity and capillary porosity when K/N fertilizer ratio was 60 kg/hm~2:60kg/hm~2.The total nitrogen,total potassium,hydrolyzed nitrogen and available potassium of each fertilization treatment in the two demonstration areas were generally higher than that of the control group,and the total phosphorus and the effective phosphorus of all the fertilization treatments were generally low.(2)Healthy breeding and strategy of grassland and ecological animal husbandry in the karst rocky desertification areaTo study effects of karst grassland fertilization on pasture-livestock,the experiments of applying ammonium sulfate,ammonium nitrate and no fertilizer(control group)on the grassland was carried out,the results showed that the sulphur content in the grass of applying ammonium sulphate was significantly higher than that in the ammonium nitrate fertilization group and the control group(P<0.01),but there was no significant difference between the ammonium nitrate fertilization and the control group.The selenium content in the grass of applying ammonium fertilization was significantly lower than that of applying ammonium nitrate and control group(P<0.01),but there was no significant difference in the selenium content between ammonium nitrate fertilization group and control group(P>0.05).The contents of selenium,copper,iron,hemoglobin(Hb),hematocrit(PCV)and the serum ceruloplasmin content(Cp),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX),blood catalase(CAT)and malondialdehyde(MD)were extreme significantly lower than those of ammonium nitrate fertilization group and the control group(P<0.01).In general,application of ammonium sulphate to grassland affects the trace element content of forage,the physiological metabolism and blood physiological and biochemical parameters of trace elements in Guizhou semi-fine wool sheep,therefore,ammonium nitrate fertilizer was more suitable for grassland with deficiency of selenium and other trace elements.To study effects of trace elements on healthy breeding of featured livestock in karst grassland,a comparative analysis of grazing experiment for Guizhou semi-fine wool sheep was carried out in normal grassland(control group)and zinc-deficient grassland(experimental group).The results showed that the Zn content in soil of the experimental group was significantly lower than that in control group(P<0.01),and there was no significant difference in the content of other elements(P>0.01).The Zn content in blood of Guizhou semi-fine wool sheep in experimental group was significantly lower than that in control group(P<0.01),and there was no significant difference in other elements between the experimental group and the control group(P>0.01).The white blood cell count(WBC),lymphocyte(LY)and neutrophils(E)in the blood of Guizhou semi-fine wool sheep in experimental group were very significantly lower than those in control group(P<0.01).The activity of alkaline phosphatase(AKP),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and catalase(CAT)in the blood of the experimental group were significantly lower than those in the control group(P<0.01),while the MDA content was significantly higher than that of the control group(P<0.01).From the above,the zinc deficiency in grassland had a significant effect on the blood physiological and biochemical parameters for livestock,and it had the most significant effect on the body’s antioxidant enzymes,it can cause abnormalities in the body’s antioxidant system function and immune function,and affect its normal growth and development.Therefore,zinc supplementation was essential for zinc deficiency in grassland and animals,and it was an important way to maintain the healthy and sustainable development of karst specific livestock industry.We selected the yellow cattle of Guanling and black goats of Guizhou in the Huajiang demonstration area,the yellow cattle of Weining and Guizhou semi-fine wool sheep in the Salaxi demonstration area to carry out the diet experiment of the balance of energy and protein on the weight of cattle and sheep.The results showed that the weight gain was significantly increased after the experiment(P<0.05),but the difference in net weight gain was not significant(P>0.05)by comparative analysis.But from the effect of weight gain,yellow cattle of Guanling,Guizhou semi-fine wool sheep and other karst characteristics of ruminant livestock showed the best effect of growth was in medium energy and protein,followed by low energy and high protein effect,and the lowest was high energy and low protein.When cattle and sheep feed on“high protein and low energy”diet,the protein in the diet was difficult to be used by cattle and sheep,which results in the waste of protein nutrition in the diet.Moderate protein and energy was the best way to balance energy and protein feeding.A comparative study of the meat quality for Guizhou’s semi-fine wool sheep with karst characteristic and Liangshan semi-fine wool sheep,Yunnan semi-fine wool sheep,Pengbo semi-fine wool sheep,Xiangxiong semi-fine wool sheep and Qinghai semi-fine wool sheep in Southwest China were carried out.The results showed that The total amino acid content of Guizhou semi-fine wool sheep was 18.34%,which was the highest in the semi-fine wool sheep of southwest.In the amino acid scoring,the essential amino acid index(EAAI)evaluation,and the essential amino acid chemical score(CS),the quality of Guizhou semi-fine wool was the best.Through the comprehensive comparison of routine nutritional composition,trace element,amino acid score,essential amino acid index and chemical score of essential amino acid of Guizhou semi-fine wool sheep and other semi-fine wool sheep in the karst region,it was found that Guizhou semi-fine wool sheep was a high-quality mutton resource.By synthesizing the main meat quality evaluation indicators such as conventional nutrition and amino acid content,the meat quality of the characteristic yellow cattle in the karst area is better than that of the Simmental cattle.(3)Mode construction and technology developmentBased on the theory of suitability and restriction theory,human-land relationship theory,etc.,the boundary conditions of the typical mode were determined,combining the structure and functional characteristics of the mode to contrast and analyze the structure and function of the mode,and constructing two overall core mode of adversity characteristics forest-grassland planting and ecological animal husbandry mode of characteristic healthy breeding in rocky desertification area of Huajiang and high-efficient grassland production and ecological animal husbandry mode of standardized characteristics healthy breeding in rocky desertification area of Salaxi.Through summarizing the existing technology and mature technology,we researched and developed a series of key common technologies such as the germination experiment device and method,and the standardized establishment of grass in the rocky desertification area.It should be based on the characteristics of its dry and hot valleys in rocky desertification area of the karst plateau-canyon,it should be research and develop key technologies such as high yield of warm season forage under the premise of maintaining water and soil restoration environment.According to site conditions,it should research and develop high-efficiency production technology of cool-season pastures in rocky desertification area of the karst plateau-mountain.(4)Demonstration application and promotionSince October 2012,the demonstration area has accumulated about 5,000 hm~2 and 2,300 heads of cattle and sheep have been demonstrated in healthy farming.in the core demonstration area.Using raster data space analysis of ArcGIS to realize the promotion of suitability evaluation in the two demonstration modes.The most suitable area for promotion in the“Huajiang Mode”in South China karst area was27.38×10~4 km~2,the suitable area for promotion area was 45.89×104 km~2,the basic suitable area for promotion was 54.69×10~4 km~2,the barely suitable area for promotion was 39.28×10~4 km~2,the unsuitable area for promotion was 27.14×10~4 km~2.The most suitable area for promotion in the“Salaxi Mode”was20.33×10~4 km~2,the suitable area for promotion was 43.47×10~4 km~2,the basic suitable area for promotion was 50.72×10~4 km~2,the barely suitable area for promotion was 45.92×10~4 km~2,and the unsuitable area for promotion was 33.26×10~4 km~2.