In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturb...In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturbance, a grazing trail was carried out during a 21-year period from 1974 at a sown grassland of the National Grassland Research Institute, located in Nishinasuno, the central area of Japan. The data sets of biomass for each mouth(from April to November)of the 21 year period were analyzed in this paper. The botanical composition of aboveground biomass varied greatly with both season and year. The biomass ratio of improved herbage species to invaded native plants gradually decreased each year. This may have been owing to meteorological factors, such as low air-temperature in winter, dry and hot summers, grassland management(including grazing intensity and fertilizer application), and inter-specific competition between native and introduced herbage plants.展开更多
[Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 tre...[Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 treatments of heavy grazing and light grazing,and each treatment contained 6 plots,with randomized complete block design. A blank control was set near test plot. Ninety disease-free and healthy 2-year-old Yunling Black Goats with consistent body condition were selected and divided into 2 groups: heavy grazing ( 55) and light grazing ( 35) . The goats were conduc- ted rotation grazing in 6 plots,and the average stocking rates were 12. 6 and 8 goat /hm 2 . The plant height,coverage,underground biomass and pasture plant nutrition of 2 treatments were measured,respectively. [Result]The cocksfoot height had significant difference with control under graz- ing conditions ( P 〈0. 05) ,while the heights of ryegrass and white clover in control plot had no significant difference with that in grazing plot ( P 〉 0. 05) . Grazing intensity had different effects on coverage of different plants; grazing utilization reduced the coverage of cocksfoot and ryegrass, which had little impact on coverage of white clover; viewed from the whole plant communities,the coverage in control plot was greater than that in grazing plot. The underground biomass in 0 -20 cm soil depth in grazing plot accounted for about 90%; with the increase of grazing intensity,un- derground biomass was decreased. The crude protein ( CP) and crude fat ( EE) content of forage decreased,while acid detergent fiber ( ADF) and neutral detergent fiber ( NDF) increased. [Conclusion]The research provided scientific basis for determination of suitable grazing system and sus- tainable utilization of pasture resources.展开更多
文摘In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturbance, a grazing trail was carried out during a 21-year period from 1974 at a sown grassland of the National Grassland Research Institute, located in Nishinasuno, the central area of Japan. The data sets of biomass for each mouth(from April to November)of the 21 year period were analyzed in this paper. The botanical composition of aboveground biomass varied greatly with both season and year. The biomass ratio of improved herbage species to invaded native plants gradually decreased each year. This may have been owing to meteorological factors, such as low air-temperature in winter, dry and hot summers, grassland management(including grazing intensity and fertilizer application), and inter-specific competition between native and introduced herbage plants.
基金funded by Scientific Research Project of Public Service Industry " Bearing Capacity and Livestock Configuration of Pasture in Different Regions (200903060)
文摘[Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 treatments of heavy grazing and light grazing,and each treatment contained 6 plots,with randomized complete block design. A blank control was set near test plot. Ninety disease-free and healthy 2-year-old Yunling Black Goats with consistent body condition were selected and divided into 2 groups: heavy grazing ( 55) and light grazing ( 35) . The goats were conduc- ted rotation grazing in 6 plots,and the average stocking rates were 12. 6 and 8 goat /hm 2 . The plant height,coverage,underground biomass and pasture plant nutrition of 2 treatments were measured,respectively. [Result]The cocksfoot height had significant difference with control under graz- ing conditions ( P 〈0. 05) ,while the heights of ryegrass and white clover in control plot had no significant difference with that in grazing plot ( P 〉 0. 05) . Grazing intensity had different effects on coverage of different plants; grazing utilization reduced the coverage of cocksfoot and ryegrass, which had little impact on coverage of white clover; viewed from the whole plant communities,the coverage in control plot was greater than that in grazing plot. The underground biomass in 0 -20 cm soil depth in grazing plot accounted for about 90%; with the increase of grazing intensity,un- derground biomass was decreased. The crude protein ( CP) and crude fat ( EE) content of forage decreased,while acid detergent fiber ( ADF) and neutral detergent fiber ( NDF) increased. [Conclusion]The research provided scientific basis for determination of suitable grazing system and sus- tainable utilization of pasture resources.