Sdudies On The Effect Of The Different Dosage Of Biochar On The Black Soil Nitrification And Respiration

Biochar can reform soil that is a favorable modifier of soil. In recent years, biochar has become a researching hotspot, because it has good adsorbability that can absorb NO₃^-. Thus it can decrease volatilization of ammonia and increase fertilizer retention capacity. The results of the study can not only guide to the utilization of waste straw, realize resource recycling, but also to reduce greenhouse gas emissions, protect the atmospheric environment farmland, improve the utilization rate of nitrogen fertilizer to provide technical support, has important practical significance. The results are as follows:?1? In the culture condition of this paper?the water content of soil was controlled as 20%, the temperature was 25?, the 4% additive of biochar was able to promote ammonium nitrogen immobilization in soil best while nitrogen ran off least. Biomass carbon keep the non commutativity ammonium nitrogen in the soil, let it not the ammonium nitrogen loss with the solution, has a very strong adsorption of ammonium nitrogen.?2? Compared with CK, all kinds of biochar treatments inhibited nitrification. The inhibited effects were remarkable but different. When the additive of biochar was 4%, nitrate nitrogen content in soil was lowest.Biomass carbon to ammonium nitrogen in the soil are at the same time, also hinders to transformation of nitrate, ammonium nitrogen and nitrate nitrogen content is low.?3? With the culturing time ascending, the gross nitrification rates of all treatments presented downtrend. The lower additives?0.5% and 1%? of biochar could inhibit the soil nitrification rate markedly whereas the higher additives?2%, 3%, 4%, 5%? of biochar would promote the soil nitrification rate.?4? The soil respiration rates of all treatments presented downtrend with culturing time prolonging. When the additive of biochar was 1% or 4%, the inhibition of soil respiration was best compared with CK and other treatments.?5? The ammonium nitrogen holding capacity of 4% additive biochar was better than 10% DCD.The inhibiting effect of 10% DCD was better than 4% biochar. Add 10% of DCD treatment on soil nitrification rate of inhibition effect is better than the low content?0.5%, 1%? of biomass carbon processing. In the later period of culture, the inhibiting effect of 1% biochar was better than 10% DCD.