| This study was taken place in Feng County, Shaanxi. We investigated the arbuscularmycorrhizal fungi (AMF) resources in trees’ rhizosphere in Pb-Zn mine area; we alsoresearched the AMF symbiosis and its relationship with soil factors, such as soil enzyme andGlomalin. The main conclusions are as follows:1.20AMF species in8genera were isolated from the rhizosphere soils of five treespecies, Glomus was the dominant genus and Rhizophagus diaphanus was the most commonspecies in this area. In all20AMF species,17species only individually appeared in one ortwo trees rhizosphere. This indicates that host plant species significantly affect the AMFcommunity structure.2.17AMF species in8genera were isolated from the rhizosphere soils of Sabinachinensis, Glomus was the dominant genus and Glomus microaggregatum was the mostcommon species found in the rhizosphere soils of Sabina chinensis. AMF species richness isnegatively correlated with lead content, and AMF spore density is highly significantlynegatively correlated with lead content (P<0.01). This indicates that high concentration leadcauses the damage to AMF, and results in the decrease of AMF species diversity.3. The AMF colonization of Sabina chinensis Linn., Platycladus orientalis L., Juglansregia L., Pistacia chinensis Linn., Fagus longipetiolata Seem., Robinia pseudoacacia Linn.,Populus purdomii Rehd., was up to44.64%on average, the highest colonization ratehappened in the rhizosphere of Sabina chinensis, which reached to56.97%. The lowestcolonization rate happened in the rhizosphere of Robinia pseudoacacia, which was28.5%.The spore density averaged2.34per gram soil and the differences between species weresignificant, the highest spore density was in the rhizosphere of Platycladus orientalis, whichreached to5.50per gram soil. The lowest spore density was in the rhizosphere of Faguslongipetiolata, which was0.50pre gram soil. The rate of AMF colonization was notcorrelated significantly with the spore density. Glomalin was highly significantly positivelycorrelated with available P and available K, and significantly positively correlated with cationexchange capacity (P<0.05), this indicates that AMF can secrete glomalin to promote theformation of soil aggregates, enhancing the fertilizer retention capacity and buffering capacity of the soil. The principal component analysis shows that available K, alkali-hydrolyzable N,available P, soil organic carbon, urease activity, total N, alkaline phosphatase activity andcation exchange capacity are the main factors of indicating the soil nutritional status in Pb-Znpolluted mine. Our results showed that AMF was significantly correlated to the soil factorsand glomalin. These were useful indicators for the building and perfecting of the indexevaluation system in heavy-metal polluted areas.4. Arbuscular mycorrhizal fungi can form a good symbiotic relationship in therhizosphere of Sabina chinensis in different sampling sites in Pb-Zn mine, the rate of AMFcolonization was up to51.05%on average, the spore density was3.84per gram soil onaverage, the rate of AMF colonization was significantly positively correlated with AMF sporedensity. Lead content was significantly negatively correlated with AMF spore density, urease,catalase and total glomalin. Available P was significantly positively correlated with AMFspore density and rate of AMF colonization. This indicates that P plays an important role inthe growth and metabolism of the AMF. Soil organic carbon and glomalin was significantlypositively correlated with cation exchange capacity. This means AMF can promote theformation of soil aggregates by the secretion of glomalin. Thus enhancing fertilizer andbuffering capacity of the soil to prevent soil nutrient loss and soil degradation. |
