Ecologicol Studies on The Forest Soil Protozoa of Mount Luojiashan and Exploration of Quantitative Methods For Soil Protozoa

The forest soil protozoa of Mount Luojia was studied quantitatively with both direct and culture counting methods from January to December in 1993.It was dicovered that the summit of the annual abundance dynamics of protozoa was in spring (March,April & May),the valley in winter (January & Febrary),and the abundance fluntuated gently in summer and fall.The results of regression analyses showed that there were obvious positive correlations between the annual dynamics of protozoan abundance and the variations of water amount and Ph value of the soil,and there was no obvious correlation between the dynamics and the variations of the soil temperature.The dominant species were Bodo edax,Trinema lineare,T.enchelys, B.globosus,Centropyxis elongata,Cryptomonas ovata,Cyclopyxis eurostoma and Cercomonas longicauda.The common species were B.edax,B.globosus,Pleuromonas jaculans,T.lineare,T.enchelys,Centropyxis elongata,Colpoda inflata,C.steinii,Leptopharynx costatus,Frontonia depressa,Cercomonas longycauda,C.cucullus and Monas minimum.The variation trend of protozoan abundance showed by the two counting methods was consistent,but the results of the culture method were 102 to 103 times as much as the ones of the direct counting method.This demonstrated that most of protozoan individuals existed in cyst forms and only small numbers in active forms in soil,and on the other hand,the culture counting method overestimated the standing crop of soil protozoa.Therefore,we believed that direct counting method gives more reliable estimations of the abundance of soil protozoa and it is better to adopt direct counting method if the objective conditions permit.