Effects Of Long-term Compost Application On Soil Health In Quzhou Station

Soil health is the foundation of terrestrial ecosystems,and it is very important to improve soil health which can maintain food security and agricultural sustainable development.This study focused on the differences among soil physical,chemical,and biological properties under different long-term composts fertilization strategies and the results of those properties were analyzed synthetically to establish the suitable fertilization strategy to improve soil health.A 20 years long-term experiment was conducted in the Quzhou station of China Agriculture University.Six treatments included no fertilizer(CK),and high dosage of organic compost(EMI),and high dosage of traditional manure(TC1),and conventional dosage of organic compost(EM2),and conventional dosage of traditional manure(TC2),and chemical fertilizer(CF).Another compost are Sludge compost and raw sludge.We use the conventional analysis methods and infrared spectrum scanning,and the delta 13 C isotope analysis,and microbial fluorescence PCR method to analysis the physical properties,and chemical properties,and biological properties,and soil microbial diversity and the structure of organic carbon.Principal component and cluster analyses were applied to get a comprehensive assessment on the effects of different fertilization strategies on soil health.The results show that:Long-term different fertilizer on soil physical and chemical properties have a significant impact on soil,it can improve the foundation soil fertility characteristics.Using different fertilizer after 21 years,soil bulk density decreased obviously,and the processing size order is EMI>TC1>EM2>TC2>CF.The sludge compost soil bulk density and porosity change is not obvious.At the same time after long-term of compost,water holding capacity of the soil is improved,the effect of biological compost is better than sludge compost effect.Long-term use of raw sludge and chemical fertilizer(CF)significantly increased the soil electrical conductivity of processing,and rotten sludge compost decrease soil electrical conductivity.Long-term of compost could enhance soil total nutrients and amount of available nutrient levels on compost soil total nitrogen,total phosphorus content were higher than that of CF treatment.In a word,soil physical and chemical properties are better in compost treatment than traditional compost and chemical fertilizer treatment.Long-term different compost significantly increase the content of soil organic carbon,and changed the composition of organic carbon and its structural characteristics.The EM compost treatment of soil organic carbon content is order to EM1>TC1>TC2>EM2>CF>CK.The EM1 and TC1 treatment significantly improved the components of activated carbon pools.The three components of organic carbon content on raw sludge treatment were significantly higher than that of control,the activated carbon pools on sludge compost treatment is the highest.Soil recalcitrant pools contains carbon hydrocarbons,carboxyl,such as fatty substance through analyzing soil IR scan.The recalcitrant pools contains more aliphatic hydrocarbons,acid anhydride and carboxyl class material in EM1 treatment.And soil organic carbon of aliphatic,hydrocarbons and carboxyl class absorption peak decreases obviously on sludge compost.Delta 13C values reflect the size of the degree of degradation organic matter;the results show that the recalcitrantcarbon pools degradates seriously on EM2 treatment.The sludge compost treatment has the same trend.Long-term of compost promoted the development of soil aggregate,aggregate grade aggregate quantity.After a long period of compost,with the increase of particle size distribution soil aggregate organic carbon content of organic carbon content is reduced after rising first,the change law is(2-1 mm)>(1-0.5 mm)>(0.5 0.25 mm)>(<0.25 mm)grade.Each processing in>2 mm diameter of the aggregate of has more aromatic substances than CK,but no absorption peak of saturated hydrocarbon.The soil micromorphological structure development degree on biological compost is better than chemical fertilizer treatment.The silt soil organic and cementing material aggregate together to form large aggregates,therefore better soil structure has developped.It has a significant effect on soil microbial biomass,composition and diversity on long-term application of different compost.Compared with fertilization of chemical fertilizer(CF)microbial carbon content on biological compost(EM1and EM2,TC1 and TC2)increased by 1.6%-6%.The more biological usage,the higher the microbial quantity increases.It has a significantly influence on the activity of soil enzymes with long-term of compost and chemical fertilizer.It found that soil microbial quantity increased significantly after long-term of compost by fluorescence quantitative PCR detection.It was more conducive to the bacteria growth on EMI and rotten sludge compost soil.Principal component and cluster analyses were applied to get a comprehensive assessment on compost test.According to the results,various biological compost test process can be divided into four groups,the use of different sludge treatment can be divided into three groups.There are 11 microbial flora in different composting process.Finally the analysis showed that the wheat yield and grain protein content has increased in long-term of compost treatment.Principal component and cluster analyses were applied to get a comprehensive assessment on the effects of different fertilization strategies on soil health.The soil heavy metal content did not exceed national standards on long-term biological compost.Use high biological compost soil health comprehensive index is the highest(0.88),followed by the use of rotten sludge compost pile soil health index(0.79),and application of chemical fertilizer treatment of soil health comprehensive index is low.It shows that long-term fertilizer can significantly increase the soil health.