桑枝和蚕沙的基础成分测定及堆肥试验

The Main Nutrients Determination and Composting Experiment of Mulberry Branches and Silkworm Faeces

桑枝和蚕沙是蚕桑生产的大宗副产物,用其制作堆肥是资源化利用和无害化处理的有效途径。测定结果表明,桑枝条的木质化程度越高,枝条的碳氮比(C/N)也越高;混入残余桑叶碎片和叶梗的蚕沙与蚕粪比较,其C/N显著降低。堆肥试验设置1号堆(100%桑枝)、2号堆(20%蚕沙+80%桑枝)、3号堆(100%蚕沙)3个处理组,测定各组堆肥腐熟过程中的物质变化及腐熟后的堆肥品质,结果显示:堆肥过程中各堆体的高温(≥50℃)持续天数由长到短依次为1号堆、2号堆、3号堆;堆肥的前60 d是堆体中各种养分物质含量变化最为剧烈的时期。各处理组堆体腐熟后,有机质含量由高到低依次为1号堆、2号堆、3号堆,有效氮、磷、钾及速效总养分含量由高到低依次为3号堆、2号堆、1号堆。综上认为:堆肥需要根据原料的组成合理调节氮源用量;2号处理组堆肥的品质最优,即在桑枝堆体中添加一定量的蚕沙,既可保证较高的有机质含量,又可提高堆肥的速效肥力。

Mulberry branches and silkworm faeces are the main by-products in sericulture.Reusing these by-products to make compost is an effective way of resourceful utilization and harmless treatment.Determination results showed that the C/N ratio of mulberry branches became higher as the lignification degree increased.The C/N ratio of silkworm faeces decreased significantly with mixing of mulberry leaves and stems.The composting experiment set up 3 treatment groups,namely,Pile No.1(100%mulberry branches),Pile No.2(20%silkworm faeces+80%mulberry branches)and Pile No.3(100%silkworm faeces).The substance changes during the compost maturation and the compost quality after maturation in each group were determined.Results showed that the days of the high temperature(≥50℃)of each pile in descending order was No.1,No.2 and No.3 during composting and various nutrient content changed the most dramatically in the first 60 days.After maturation of each pile,the organic matter content in descending order was No.1,No.2 and No.3,and the effective nitrogen,phosphorous,potassium and the total quick effective nutrients content in descending order was No.3,No.2 and No.1.To sum up,composting required reasonable adjustment of nitrogen application based on the composition of raw materials.Pile No.2 had the best quality of compost which indicated that adding a certain amount of silkworm faeses to mulberry branch pile could guarantee comparatively high organic matter content as well as improve the quick effective fertility of compost.