In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental
Natural grassland in the West of Northeast China is located in 40° 0′ - 43° 5′ N latitude and 117° 0′ -127° 5′ Elongitude. It lies in the Lisp River Val
Instead of pure bacteria, induction mutation of activated sludge by ultraviolet (Uv) was studied and used to treat pulping wastewater by continuous-flow. The re