摘要
通过野外取样和室内分析,初步研究了科尔沁沙地两种生物结皮在干、湿两种处理下土壤种子库种类组成、密度以及物种多样性等特征。结果表明:①科尔沁沙地藻结皮和苔藓结皮土壤种子库的总密度为干旱藻结皮<湿润藻结皮<干旱苔藓结皮<湿润苔藓结皮。两种结皮上种子库的数量存在显著差异,对于干、湿处理的两种结皮,苔藓结皮上种子库的总密度均大于藻结皮上种子库的总密度;②两种生物结皮在干旱、湿润两种处理中共出现了6科、15种植物,种子库的组成以一年生草本植物、中生植物为主,二者百分比均超过76%;③在干旱藻结皮、湿润藻结皮、干旱苔藓结皮和湿润苔藓结皮上,种子库物种多样性表现出湿润处理下的结皮高于干旱处理的结皮。由此表明,在半干旱的科尔沁沙地,水分是限制结皮土壤种子库中种子萌发的主要因子,而生物结皮则通过对水分入渗与再分配的调控作用影响结皮种子库中种子的萌发。
The present paper taking Horqin sand land as the research region,by field sampling,the algae crust in semi-fixed dune and moss crust in fixed dune were collected. The two kinds of crusts were arranged in dry and moist treatments to analyze the sorts,densities and species diversity of seed bank.Some conclusions can be drawn from this study.①The total density of soil seed bank increased with the order of dry algae crust 〈 moist algae crust 〈 dry moss crust 〈 moist moss crust.Under each water treatment,there were significantly differences between algae crust and moss crust.②There were fifteen kinds of plants belong to 6 family germinated in the two sorts of crusts,and annual herbaceous plants and mesophyte were dominant in the seed banks（76.27%～100%）,mainly Chenopodium acuminatum,Eragrostis pilosa and Aristida adscensionis.③Due to the different treatment of crust,crusts under moist condition had higher species diversity,which proved in semi-arid region of Horqin sandy land,biological crust had direct effect on soil seed bank by the function of changing the water infiltration and reassignment.It was also indicate water is the main restrictively factor to constrain the germination of biological crust seed bank.
出处
《水土保持学报》
CSCD
北大核心
2007年第6期187-191,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(40601008)
中科院寒旱所创新项目(O650444001)
关键词
科尔沁沙地
生物结皮
土壤种子库
Horqin sandy land
biological crust
soil seed bank
