毛乌素沙地沙柳根际AM真菌资源和空间分布

2006年10月,从毛乌素沙地4个自然生境下沙柳(Salix psammophila)根际0～10,10～20,20～30,30～40和40～50 cm 5个土层分别采集土壤样品,研究了沙柳根际AM真茵种类和空间分布.结果表明,在分离的4属12种AM真菌中,摩西球囊霉(Glomus mosseae)和缩球囊霉(Glomus constrictum)是优势种.AM真菌分布和定殖与样地生态条件和采样深度密切相关,易误巨孢囊霉(Gigaspora decipiens)只出现在米脂样地,网状球囊霉(Glomus reticulatum)等只出现在东胜样地,双网无梗囊霉(Acaulospora direticulatum)和黄色盾巨孢囊霉(Scutellospora armeniaca)只出现在榆林样地,卷曲球囊霉(Glomus convolutum)只出现在伊金霍洛旗中科院研究站样地.AM真菌孢子密度和总定殖率最大值都出现在东胜样地,孢子密度和菌丝、菌丝套定殖率的最大值都出现在0～20 cm土层.AM真菌孢子密度与土壤温度和速效P呈极显著正相关,泡囊定殖率与土壤温度和速效P呈极显著正相关,与土壤有机质呈显著负相关;丛枝定殖率与速效P呈极显著正相关;总定殖率与速效P呈正相关.可见,沙柳根际AM真菌分布和定殖具有明显的空间并质性,且与土壤速效P等土壤因子关系密切.

Resource and Spatial Distribution of Arbuscular Mycorrhizal Fungi from the Rhizospere of Salix Psammophila in the Maowusu Sandlands

In October 2006,the soil samples were collected from the rhizospheres of Salix psammophila from 0～10,10～20,20～30,30～40,40～50 cm depth soil layers in four natural environments of the Maowusu Sandlands,diversity and spatial distribution of arbuscular mycorrhizal fungi were investigated.Using oxidize method with the heavy chrome sour potassium,Phillips and Hayman method etc.,the results showed that there were four genera and twelve species of AM fungi isolated from the the soil samples under the Salix psammophila.Glomus mosseae and Glomus constrictum were dominant species,the colonization and spatial distribution of arbuscular mycorrhizal fungi had a close relationship with the different ecological environments and the depths of the soil layers,for example,Gigaspora decipiens only occured in Mizhi site,Glomus reticulatum,Glomus pansihalos,Acaulospora rehmii and Scutellospora calospora only occured in Dongsheng site.Glomus direticulatum and Scutellospora armeniaca only occured in Yulin site,Glomus convolutum only occured in Chinese Science Recearch Center in Yijinhuoluoqi site.The average of spore density and the total colonization in Dongsheng site were highest among of the four sites.The highest spore density,percent colonizations of hyphal and mycelial mantle all existed at the 0～20 cm sections.The spore density had a very positive correlation with the soil temperature and the soil available P,The percent colonizations of vesicle had a prominently positive correlation with the soil temperature and the soil available P,and had a negative correlation with organic matter;the percent colonization of arbuscular had a positive correlation with the soil available P;the total percent colonization of vesicle of AM fungi had a prominently negative correlation with the soil available P.Therefore,the spatial distribution and colonizations of AM fungi from the rhizospere of salix psammophila had a significantly spatial difference and had a consanguineous correlation with the edaphic factor including the soil available P ect.