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New Nitrification Inhibitor Dmp-d

Posted on:2005-07-30Degree:MasterType:Thesis
Country:ChinaCandidate:S R LuanFull Text:PDF
GTID:2193360125452763Subject:Botany
Abstract/Summary:PDF Full Text Request
In the world agriculture, it is an important problem that the use efficiency of N fertilizer is very low and N-loss is becoming more serious with the development of agriculture. Some measures have been taken to improve nitrogen fertilizer efficiency and to minimize negative environments effect that was caused by nitrogen in the nitrate form (nitrate leaching and denitrification losses). Using nitrification inhibitors in nitrogen fertilizer is one of the hopeful methods. The purpose of this research is to find a new effective nitrification inhibitor, which does little harm to people and beasts and further to serve our agriculture.The effect of DMP-D as nitrification inhibitors were studied by house culture in different soil. For comparison, dicyandiamide (DCD), a chemical nitrification inhibitor was also used in the experiment. The influence of DMP-D on soil potential nitrification and microorganism were also studied.DMP-D had some effect on the number of the soil microorganisms, can significantly reduce the activity of soil microorganisms and slow down the nitrification potential. DMP-D retard the natural transformation of ammonium into nitrate, by inhibiting the activity of Nitrossmous SPR, the bacteria responsible for the first step of the nitrification process (conversion of ammonium to nitrate). Compare to the control without DMP-D, the addition of DMP-D to N fertilizer resulted in higher levels of NH4+-N and lower levels of NOa'N in various soils during the whole experiment period. DMP-D reduced the rate of nitrification and had no significant effect on N-loss by NH3.DMP-D is a new and highly efficient nitrification inhibitor, which is effective at low application rates in the salt soil. Although DMP-D was applied at rates approximately 4 times lower than DCD in the salt soil, the ability of inhibition of DMP-D is much better than DCD. The inhibitory effect of DMP-D and DCD on the three fertilizers in the threesoil samples was in a descending order of ammonium sulfate>ammonium bicarbonate>urea.With the increasing amount of application or the decrease of the soil temperature, the nitrification inhibition of DMP-D would become obvious. DMP-D may be persistent and had significant nitrification inhibition under low soil temperature. The decomposition of DMP-D could significantly reduce nitrification inhibiting efficiently. KH2PO4 could improve the steady of DMP-D in various soils and prolong nitrification inhibition also.During the wheat pot experiments, DMP-D could reduce mineral N loss through leaching. In compare to the control plots without DMP-D, the average nitrate leaching of DMP-D treated plots were 50% lower. It is obvious that DMP-D can improve nitrogen uptake and can benefit for the growth of the wheat, without any apparent phytotoxicity. To some extent, DMP-D could stimulate the growth of winter wheat growing.The result of the experiment indicated that DMP-D could be used as nitrification inhibitor. The nitrification inhibition of DMP-D did not seem to be as good as DCD in the red soil and yellow soil, while was much better than DCD in the salt soil.Because DMP-D is a new substance as nitrification inhibitor, it is necessary to be submitted to extensive toxicology and ecotoxicology test. The inhibitory effect of DMP-D on nitrification should be studied both in further model experiments as well as in field experiments under various soil conditions. In addition, fur the research is necessary to evaluate the role of soil parameters for the long-term inhibition effect of DMP-D.
Keywords/Search Tags:DMP-D, dicyandiam ide(DCD), NH4+-N, NO3--N, nitrification inhibition, wheat
PDF Full Text Request
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