Radhakrishnan Srinivasan, Varadharajan Mohan
Division of Forest Protection, Institute of Forest Genetics and Tree Breeding, Coimbatore, India.
J Basic Microbiol. 2016 Jun;56(6):662-9. doi: 10.1002/jobm.201500639. Epub 2016 Feb 29.
Soil is a complex and dynamic biological system. Agroforestry systems are considered to be an alternative land use option to help and prevent soil degradation, improve soil fertility, microbial diversity, and organic matter status. An increasing interest has emerged with respect to the importance of microbial diversity in soil habitats. The present study deals with the status of microbial diversity in agroforestry systems in Tamil Nadu. Eight soil samples were collected from different fields in agroforestry systems in Cuddalore, Villupuram, Tiruvanamalai, and Erode districts, Tamil Nadu. The number of microorganisms and physico-chemical parameters of soils were quantified. Among different microbial population, the bacterial population was recorded maximum (64%), followed by actinomycetes (23%) and fungi (13%) in different samples screened. It is interesting to note that the microbial population was positively correlated with the physico-chemical properties of different soil samples screened. Total bacterial count had positive correlation with soil organic carbon (C), moisture content, pH, nitrogen (N), and micronutrients such as Iron (Fe), copper (Cu), and zinc (Zn). Similarly, the total actinomycete count also showed positive correlations with bulk density, moisture content, pH, C, N, phosphorus (P), potassium (K), calcium (Ca), copper (Cu), magnesium (Mg), manganese (Mn), and zinc (Zn). It was also noticed that the soil organic matter, vegetation, and soil nutrients altered the microbial community under agroforestry systems.
土壤是一个复杂且动态的生物系统。农林业系统被视为一种替代性土地利用方式，有助于防止土壤退化、提高土壤肥力、微生物多样性和有机质状况。人们对土壤栖息地中微生物多样性的重要性越来越感兴趣。本研究探讨了泰米尔纳德邦农林业系统中微生物多样性的状况。从泰米尔纳德邦古德洛尔、维鲁布尔姆、蒂鲁瓦纳马莱和埃罗德县的农林业系统不同田地采集了八个土壤样本。对土壤中的微生物数量和理化参数进行了量化。在不同的微生物种群中，在所筛选的不同样本中，细菌种群数量最多（64%），其次是放线菌（23%）和真菌（13%）。值得注意的是，微生物种群与所筛选的不同土壤样本的理化性质呈正相关。细菌总数与土壤有机碳（C）、含水量、pH值、氮（N）以及铁（Fe）、铜（Cu）和锌（Zn）等微量营养素呈正相关。同样，放线菌总数也与容重、含水量、pH值、C、N、磷（P）、钾（K）、钙（Ca）、铜（Cu）、镁（Mg）、锰（Mn）和锌（Zn）呈正相关。还注意到，农林业系统下的土壤有机质、植被和土壤养分改变了微生物群落。
