基于木本泥炭快速构建红壤新垦耕地优质耕作层技术与效果

Techniques and Effects of Quickly Constructing High-quality Tillage Layers for Newly-cultivated Arable Land in Red Soil and Paddy Field Based on Woody Peat and Organic Materials

为了探究木本泥炭对红壤岗地新垦耕地优质耕作层构建的机理以及木本泥炭相对于其他有机物料对红壤新垦耕地的改良效果,采用田间小区试验的方法,研究添加不同有机物料对红壤新垦耕地0—20cm耕作层土壤理化性质和微生物生物量以及水稻产量的影响。试验共设6个不同处理:CK(不添加改良材料)、M30FS(木本泥炭30t/hm2+腐熟秸秆3t/hm2+石灰石粉3.75t/hm2)、M15FS(木本泥炭15t/hm2+腐熟秸秆3t/hm2+石灰石粉3.75t/hm2)、CFS(生物炭15t/hm2+腐熟秸秆3t/hm2+石灰石粉3.75t/hm2)、OFS(有机肥15t/hm2+腐熟秸秆3t/hm2+石灰石粉3.75t/hm2)和FS(腐熟秸秆3t/hm2+石灰石粉3.75t/hm2)。结果表明:(1)与对照相比,添加木本泥炭与有机物料处理显著降低了耕作层土壤容重,提高了土壤总孔隙度和pH,且添加木本泥炭与有机物料处理中土壤肥力均有不同程度提高,其中土壤有机质、全氮、全磷和全钾含量分别提高了36.41%～88.53%,2.22%～37.78%,6.25%～93.75%和27.57%～85.60%,土壤硝态氮、铵态氮、有效磷和有效钾含量分别提高了17.21%～134.85%,1.42%～72.76%,8.71%～156.79%和12.99%～332.39%。(2)添加木本泥炭与有机物料处理对耕作层土壤微生物生物量影响比较明显,与对照相比,各处理中土壤微生物量碳和氮含量分别显著增加了52.95%～219.00%和121.45%～548.73%。(3)添加木本泥炭与有机物料处理中水稻产量均明显提高,其中M30FS增产效果最明显,增幅为39.53%。(4)利用聚类分析方法将添加不同有机物料处理下新垦耕地耕作层土壤质量等级划分为3级,分别为:一级(M30FS)、二级(M15FS,OFS,CFS)、三级(FS,CK),其中经M30FS处理后土壤质量水平等级最高。添加木本泥炭与有机物料可显著降低新垦耕地耕作层土壤容重,提高土壤总孔隙度和pH,解决了红壤黏重和酸化的特征,且土壤养分和微生物量碳、氮含量均得到了提高,改善了土壤理化性状和生物学特征,提高了水稻产量,其中添加30t/hm2木本泥炭对红壤新垦耕地优质耕作层构建效果最明显。

In order to explore the mechanism of woody peat cultivation on the high-quality tillage layer in the newly cultivated land in red soil and the improvement effects of woody peat over other organic materials on the new cropland in red soil,a field experiment was conducted to study the effects of different organic materials addition on soil physicochemical properties,microbial biomass in0-20cm red soil of arid land and rice yield.Six different treatments included:CK(without adding modified material),M30FS(woody peat30t/hm2+straw decay3t/hm2+limestone powder3.75t/hm2),M15FS(woody peat15t/hm2+straw decay3t/hm2+limestone powder3.75t/hm2),CFS(biochar15t/hm2+straw decay3t/hm2+limestone powder3.75t/hm2),OFS(organic fertilizer15t/hm2+straw decay3t/hm2+limestone powder3.75t/hm2),FS(straw decay3t/hm2+limestone powder3.75t/hm2).The results showed that:(1)Compared with the control,the addition of woody peat and organic materials significantly reduced the soil bulk density in tillage layer,improved the soil total porosity and pH.Soil fertilities were also increased after addition of woody peat and organic materials with the varying degrees of improvement,the contents of soil organic matter,total nitrogen,total phosphorus and total potassium increased by36.41%to88.53%,2.22%to37.78%,6.25%to93.75%and27.57%to85.60%,respectively,and ammonium nitrogen,available phosphorus and available potassium increased by17.21%~134.85%,1.42%~72.76%,8.71%~156.79%and12.99%~332.39%,respectively.(2)Adding woody peat and organic materials had a significant effect on soil microbial biomass in tillage layer.Compared with the control,the soil microbial biomass carbon and nitrogen increased significantly by52.95%to219.00%and121.45%to548.73%respectively.(3)The rice yield increased significantly with the application of woody peat and organic materials,of which M30FS gave the biggest increase of39.53%in production.(4)The soil quality of cultivated land under different treatment was divided into3grades by cluster analysis:first grade(M30FS),second grade(M15FS,OFS,CFS),and third grade(FS,CK),among which soil quality level was the highest under M30FS.The addition of woody peat and organic materials could significantly reduce soil bulk density in tillage cultivated layer,alleviate the viscous and acidification in red soil through improving soil total porosity and pH,and increase the soil nutrient and microbial biomass carbon and nitrogen contents,improve soil physical,chemical and biological properties,and finally increase rice yield.In a word,the addition of30t/hm2of woody peat had the most obvious effect on the construction of high-quality tillage layers of new cropland in red soil.