The Study On The Characteristics Of Microorganism Of Livestock Dung In The Process Of Decomposition

Dung deposition was the important repository of nutrients in grazing ecosystem, and also an important part of material recycling. Microbial was the main factor influencing the decomposition of dung deposition. Studying the microbial activity in the process of dung deposition decomposition was the basic for a thorough comprehensive understanding of dung decomposition characteristics of grazing ecosystem, and also had a practical significance for scientific management and utilization on grazing ecosystem. In Baiyinxile Ranch in Xilinguole of Inner Mongolia from June,2008 to November,2009. Changes of microbial activity, enzyme activity, respiratory rate and calorific values were measured in the decomposition process of horse, cattle and sheep dung with two different approaches which were on or under the ground artificially. The main results were showed as follows:1.In fresh dung of these three animals, bacterial and fungus abundance were the highest in horse dung, the second was cow dung, the lowest was sheep dung, actinomycetes number in three dung had no obvious differences. In the decomposition of dung, all microbial biomass of three categories had a general uptrend. With the dealt under the ground, actinomycetes and fungus number in horse and sheep dung increased and decreased respectively, and didn't change significantly in cow dung; bacteria number seemed not been influenced with the dealt under the ground.2. The protease activity was low in fresh dung of these three animals. In decomposition process, the activity increased obviously, and all showed high when decomposed 30 and 90days. Protease activity of horse dung which buried under the ground became lower but cow and sheep dung appeared opposite. The order of urease activity in fresh dung samples were: horse dung> cattle dung> sheep dung. When decomposed 30 days, urease activity in horse and cow dung decreased but increased in sheep dung, and then all remained constant in three dung. Urease activity in three dung had no discernible effect with the dealt under the ground. Cellulase activity was the highest when decomposed 30d, with the decomposition prolonged, activity decreased and became lowest when decomposed 60 or 90days, and then increased.3. The respiration rate order of fresh dung were horse dung> sheep dung > cattle dung. With the decomposition prolonged, respiration rate of three kinds of grazing dung deposition declined overall. Compared with the dealt the dung on the ground, lowering extent which buried in the ground was smooth. Respiratory rate of dung which under the ground was significantly higher than it's on the ground. But the respiratory rate of cattle and sheep dung which on the ground was higher than its under the ground when decomposed 1 month.