Characteristics of seed rain on abandoned slopes in the hilly-gullied Loess Plateau, Northwest China
The objective of this study was to analyze the dynamic characteristics of seed rain on abandoned slopes in the hilly-gullied Loess Plateau region and identify the relationship between seed rain and standing vegetation.Three abandoned slopes were chosen as sampling sites in Zhifanggou watershed.Thirty traps were installed at each site to collect seed rain from October 2010 to April 2013.Standing vegetation was surveyed to identify dominant species in August 2011 and 2012,respectively.Thirty-seven species belonging to seventeen families were identified in the seed rain,and the dominant species,i.e.,Lespedeza davurica,Astragalus scaberrimus,Setaria viridis,Cleistogenes squarrosa,Stipa bungeana,Bothriochloa ischcemum,Artemisia scoparia,A.gmelinii,and Heteropappus altaicus,took up to 95.8％ of the total seed rain.Three species in seed rain were not found in the standing vegetation.The Sorensen similarity index between seed rain and standing vegetation was 0.77.Seed rain densities were 3737 and 6449 seeds · m-2 in May 2011-April 2012 and May 2012-April 2013,respectively,and alternate bearing existed.During the study period,seed rain from different positions varied from 3853 to 37923 seeds · m-2and belonged to 7-15 species.The results indicated the space limitation of seed dispersal.Seed rain densities were in the middle of the pack compared with similar ecosystems in other studies.High temporal and spatial heterogeneity of seed rain was observed because of rainfall,micro-topography and so on.
国家科技期刊平台
NSTL
万方数据
维普
