This study investigated the effects of various grazing systems, including continuous grazing, rotational grazing, and no-grazing systems, on the community biomass in the Stipa breviflora Griseb desert grassland during...This study investigated the effects of various grazing systems, including continuous grazing, rotational grazing, and no-grazing systems, on the community biomass in the Stipa breviflora Griseb desert grassland during the grazing seasons in 2005, 2006, and 2007, based on study sites established in 1999. We found that the seasonal dynamics of the aboveground biomass were quite similar among the three treatments, which reached peak values in period from August to September during each study year. The continuous grazing system reduced the aboveground biomass from 2005 to 2007 under drought conditions, and the rotational grazing and no-grazing systems maintained more aboveground biomass than the continuous grazing system did. The belowground biomass declined with the increase of soil depth among the three treatments, and in the surface 20-cm soil layer it accounted for more than 60% of the total biomass. The belowground biomass was found to be highly correlated with soil depth under rotational grazing. The total belowground biomass within the 0--100-cm soil layer for rotational grazing was sig- nificantly higher than for continuous grazing and no-grazing, and had 15,775 kg/ha more biomass. Our results demonstrate that conservative rotational grazing can alleviate grassland deterioration by reserving more aboveground and belowground biomass than the continuous grazing system does.展开更多
We studied a soil seed bank in the Stipa breviflora desert steppe under three grassland management systems, namely continuous grazing, rotational grazing, and no grazing, from 1999 until 2007. The germinable seed bank...We studied a soil seed bank in the Stipa breviflora desert steppe under three grassland management systems, namely continuous grazing, rotational grazing, and no grazing, from 1999 until 2007. The germinable seed bank species in rotational, continuous and no gazing were 11, 9 and 8 species, respectively. Rotational grazing increased the number of seed bank plant species and perenni- al grasses. The density of germinal soil seed bank was significantly higher in the enclosed area (19,533.33 seeds/m2) than those in rotational (3,233.33 seeds/mz) and continuous grazing areas (2,553.60 seeds/m2). The vertical distribution of the soil seed bank had a similar trend: 75.06%-83.19% of the seeds are distributed in the top 0-5 cm soil layer, 14.16%-21.68% in the 5-10 cm lay- er, and 2.65%-4.95% in the 10-15 cm layer, which varied between the grazing treatments. Density of the soil seed bank was sig- nificantly higher in the enclosed area, and there was no significant difference between rotational and continuous grazing. The Margalef and Shannon-Wiener indices for the soil seed bank were higher for rotational grazing treatment than for continuous grazing. The Sorensen's similarity index for the soil seed bank between the enclosed and rotational grazing areas reached 0.857.展开更多
基金funded by basic special funding from the central public welfare scientific research institutes (No.202-21)public sector projects in the Ministry of Agriculture(Nos. 201003019,201003061)scientific and technological innovation and incentive funds of Inner Mongolia autonomous region and major state basic research development program of China (973 Program) (2010CB833502)
文摘This study investigated the effects of various grazing systems, including continuous grazing, rotational grazing, and no-grazing systems, on the community biomass in the Stipa breviflora Griseb desert grassland during the grazing seasons in 2005, 2006, and 2007, based on study sites established in 1999. We found that the seasonal dynamics of the aboveground biomass were quite similar among the three treatments, which reached peak values in period from August to September during each study year. The continuous grazing system reduced the aboveground biomass from 2005 to 2007 under drought conditions, and the rotational grazing and no-grazing systems maintained more aboveground biomass than the continuous grazing system did. The belowground biomass declined with the increase of soil depth among the three treatments, and in the surface 20-cm soil layer it accounted for more than 60% of the total biomass. The belowground biomass was found to be highly correlated with soil depth under rotational grazing. The total belowground biomass within the 0--100-cm soil layer for rotational grazing was sig- nificantly higher than for continuous grazing and no-grazing, and had 15,775 kg/ha more biomass. Our results demonstrate that conservative rotational grazing can alleviate grassland deterioration by reserving more aboveground and belowground biomass than the continuous grazing system does.
基金Demonstration of Grass Digital Monitoring,Control and Decision-making Techniques (2008GB23260400)Recovery of Degraded Vegetation in Inner Mongolia and Directed Economic Plants Industrial Growing Base,the Research of Forage Yield Remote Sensing Estimation and Carrying Capacity in Hulunbeir Grassland,the National high Technology Research and Development Program of China(2006AA10Z241)+1 种基金National Science and Technology Support Program (2006BAC01A12,2006BAD16B05-2)Modern Agricultural Technology System of Special Funding
文摘We studied a soil seed bank in the Stipa breviflora desert steppe under three grassland management systems, namely continuous grazing, rotational grazing, and no grazing, from 1999 until 2007. The germinable seed bank species in rotational, continuous and no gazing were 11, 9 and 8 species, respectively. Rotational grazing increased the number of seed bank plant species and perenni- al grasses. The density of germinal soil seed bank was significantly higher in the enclosed area (19,533.33 seeds/m2) than those in rotational (3,233.33 seeds/mz) and continuous grazing areas (2,553.60 seeds/m2). The vertical distribution of the soil seed bank had a similar trend: 75.06%-83.19% of the seeds are distributed in the top 0-5 cm soil layer, 14.16%-21.68% in the 5-10 cm lay- er, and 2.65%-4.95% in the 10-15 cm layer, which varied between the grazing treatments. Density of the soil seed bank was sig- nificantly higher in the enclosed area, and there was no significant difference between rotational and continuous grazing. The Margalef and Shannon-Wiener indices for the soil seed bank were higher for rotational grazing treatment than for continuous grazing. The Sorensen's similarity index for the soil seed bank between the enclosed and rotational grazing areas reached 0.857.