| Composting is a traditional and effective approach to treat animal manure with crop straws for its recycling,reduction and harmless.The traditional composting operation takes too long time to get complete maturity,therefore,some manufactures sell products that have not been complete maturity to the market,which not only has negative effect to their credibility but also causes damage to farmland crops.There are two options available to solve this problem,one is to shorten the required time through a scientific and effective way,and the other one is to establish a convenient and efficient system to accurately the qualify of the composting product.This paper focuses on dairy manure,swine manure and crop straws which are the most common agricultural waste in Shanghai,and presents the problem of compost maturity combining with series compost experimentation in the artificial climate chamber.First of all,the most proper ratio for starting should be determined,next the required time to full maturity would be worked out,and then the influence of special additional microbial would be discussed.Followed by the relativity analysis of maturity indexes in experiments,an efficient system for control of compost quality can be set up on the basic of trational physics, chemistry and biology indexes.The conclusions are as follows:1.The effect of initial character on compost maturity was studied. The results have showed that the initial moisture and C/N ratio had the significant relation to the compost.The most appropriate moisture of the starting compost was between 50%and 60%,and the C/N ratio was about 35%.2.The effect of the composting time on the quality of maturity has been studied.The results have showed that the longer the dairy manure composting lasted for,the better the quality taken on,but it was useless for prolong the composting time after the compost achieved complete maturity So,in the condition of without any additional microbes,dairy manure and crop straws compost showed a satisfactory quality after 2 months,and the swine manure and crop straws compost need 3 months or more.3.A comparison of composting of dairy manure and crop straws inoculated with and without additional microbial inoculation has been investigated.The variations of the process indexes related to composting maturity have been studied.The results have showed that,in the composting process of 60 days,the temperature rose rapidly at the initial stage,and the duration of high temperature of the composting with microbial inoculation was 2-3 days longer than the composting without. Although the pH value,moisture and C/N ratio had no significant difference between the two composting processes,the biological indexes had significant differences.It was found that the composting with microbial inoculation could reach the maturity 10 days earlier than the traditional composting.The results of economic analysis of microbial inoculation in composting indicated that,although the microbial inoculation could increase the compost quality to some extent,the cost of microbial inoculation needs to be reduced to gain an economic benefit.4.Compared with the indexes related to composting maturity be tested,the following 6 indexes:temperature,pH value,moisture,C/N ratio,germination index,and root establishment index were chosen to establish an Index System for the compost quality control,as these indexes could reflect the basis character and the maturity process,have the high correlation with the other indexes,represent the change discipline of the other indexes and could be easily pre-treatment and easily tested.The experimental results indicated that,when the temperature was above 50℃for about 5-15 days;pH value was at alkalescency;the moisture ratio was under 0.5;the C/N was about 20;the GI was above 150%and the height of root establishment was higher than 25cm,the composting performed stabilized and fully maturity.
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