| The Three-River(Yellow River,the Yangtze and the Lancang River)Headwaters Region(TRHR)having an area of 366,000 square kilometers,located in the hinterland of the Qinghai-Tibet Plateau and called as the "Asian Water Towers",which is also important for local animal husbandry.However,the effect of climate change and human activity interaction has accelerated the degradation of the grasslands in Qinghai-Tibetan plateau,threatening the ecosystem key functions of grasslands,like the conservation of biodiversity and water supply in the TRHR area.Thus,the national government established the TRHR Nature Reserve and National Park to protect the fragile grassland ecosystem in this area and several notable results were achieved.In this background,the eco-friendly farm factory union(FFU)for livestock husbandry emerged as one of the important industry leading to achieve sustainability in the area.This research mainly focuses on the nutrient recycling among the grassland,livestock production and river systems.18 farm factory unions(FFU)were randomly selected as the research unit in the TRHR Region.During this study,forage samples from native,degraded and artificial grasslands,the dung samples of livestock and water samples of the river that is next to the FFU were all collected within each of FFU respectively.Then the nutrient contents of the circulating chain(soil-vegetationfeces-water)were determined.A comprehensive index(CI)was developed to evaluate the pasture quality,and then relationship between nutrient(nitrogen and phosphorus)and the CI were analyzed using the correlation and regression methods.Additionally,by combining production scale with the economics of the 18 FFU,the sustainable development strategy of eco-friendly husbandry was analysed and discussed in TRHR.During this study,following major results obtained are as follow:1.The results showed that the development of FFU has already realized theintegration of the herdsman,pasture and livestock,which has led to the development of local animal husbandry in the direction of up scaling and intensification,improved the income structure of herders,and promoted the transformation and development of local animal husbandry.The net average annual income of 18 FFU was 67,000 yuan where the highest value was 3.39 million yuan and the per capita annual dividend was3225.92 yuan.The average grazing intensity was 1.3 sheep units/ha.At the same time,88% of the FFU’s net income comes from animal husbandry.2.Total vegetation cover,species richness and the aboveground biomass of the non-toxic plants all were reduced on degraded grasslands.Whereas the planting grassland improved the vegetation cover and the aboveground biomass,but the effect on the richness of the species is not significant.In addition,from forage quality aspect,nitrogen and phosphorus contents were found in order of,natural grassland> degraded grassland> artificial grassland.The net income of the FFU was positively related to the forage yield and the N and P content in the native grassland.3.Grassland degradation had reduced soil moisture content,soil total nitrogen,soluble inorganic nitrogen,soluble nitrogen,and soluble organic carbon,but increased soil pH.The artificial grassland found to have increased soil moisture content,soil total nitrogen,soluble inorganic nitrogen,soluble nitrogen and soluble organic carbon to a certain extent,but had little effect on soil pH.At the same time,the artificial grassland showed increased content of soluble inorganic nitrogen,soluble nitrogen and soluble organic carbon when these were located near the river.4.The forage yield of native grassland and artificial grassland was significantly correlated with soil total nitrogen contents.The soil water content was positively correlated with the total nitrogen storage of artificial soil.The soil pH was negatively correlated with the total nitrogen storage of artificial grassland.At the same time,the total nitrogen and total phosphorus contents of grasses on artificial grasslands was significantly positively correlated with the total nitrogen nutrition of grassland soil.The vegetation nutrient contents of artificial grassland,natural grassland and degraded grassland were significantly positively correlated with soil moisture and negatively correlated with soil pH.There was a significant positive correlation among soil available nitrogen,total nitrogen nutrients,carbon and nitrogen nutrients.Soil pH was significantly negatively correlated with soluble fast-acting nitrogen in different grasslands.In natural grassland,there was a significant positive correlation between grazing intensity,fecal nutrient content,cumulative amount of manure nutrient perunit area,water carbon and nitrogen contents.5.Although the coefficient of variation(CV)of artificial grassland is relatively higher,the production of the both natural and artificial grassland increased,improving the comprehensive indexes and stability of grassland along with the net income of FFU.In summary,the carbon,nitrogen,phosphorus(vegetation,soil and surrounding water body included),pH and water holding capacity of differing types of grassland(the natural,degraded and artificial)under FFU mode are variable in TRHR,but these are far away from the environmental risk of the grassland ecosystem;The improvement of comprehensive levels and stability of grassland along the income of the FFU.For the future development,attentions should be paid to the improve the nitrogen,phosphorus and totality of the grassland ecosystem,meanwhile,the nutrients monitoring of the surrounding water body should not be neglected.The environmental risks caused by the intensification of the animal husbandry should not be ignored and eliminated.From this ecosystem based comprehensive study involving interaction of soil-vegetation-livestock-water and herders.We have concluded that the common development of the cooperative economy and the ecology of the three-river source region will be realized in the near future as the more result oriented findings will be obtained and concluded. |
PDF Full Text Request