Effects of different land use patterns on the soil microbial community diversity in montane region of eastern Liaoning Province, China.

Abstract

An experiment was conducted to examine the differences of soil microbial diversity across different land use patterns in montane region of eastern Liaoning Province, China. The relationships between soil physicochemical properties and soil microbial diversity in five different land use types, including Quercus mongolic forest, shrubland, Larix gmelinii plantation, Pinus koraiensis plantation, and Zea mays cropland were analyzed by Biolog-Eco method. The results showed that both soil total C and N contents were the highest in the Q. mongolica forest, which were 57.74 and 4.40 g·kg-1, followed by shrubland, but only 17.46 and 1.31 g·kg-1 in the Z. mays cropland, respectively. There were significant differences in microbial utilization rate of different land use types. The carbon utilization capacity by soil microbial communities was following the order of Q. mongolica forest > shrubland > L. gmelinii plantation > P. koraiensis plantation > Z. mays cropland, indicating that soil microbial metabolism and activity in Z. mays cropland were the lowest. The Shannon diversity index (2.997), Simpson diversity index (0.942) and McIntosh diversity index (5.256) of soil microbial community in the Z. mays cropland were significantly lower than those in other ecosystems. The average absorbance value (AWCD) was associated with Simpson diversity index and McIntosh diversity index. Esters, alcohols and amines were the primary carbon sources for the differentiation, which might be due to a joint action of many factors such as litter, soil nutrients, and specific soil microorganisms. The soil nutrient and soil microbial community diversity in forest land after reclamation sharply decreased, causing the loss of soil fertility and productivity. The region should keep the Q. mongolica forest, which could help restore soil fertility.