摘要
【目的】研究不同秸秆转化生物炭对红壤性水稻土养分含量及微生物群落结构的影响差异,为土壤改良和秸秆资源的合理利用提供理论参考。【方法】以水稻和玉米秸秆300℃、400℃和500℃裂解得到的生物炭为添加材料,以发育于第四纪的红壤性水稻土为供试土壤,通过135 d室内培育试验,研究秸秆生物炭添加对红壤性水稻土p H、有机碳和养分含量、土壤微生物生物量碳(MBC)的影响,及其对磷脂脂肪酸(PLFA)表征的微生物群落结构的影响。试验共设7个处理:对照(CK)、添加水稻秸秆炭300℃(RB300)、400℃(RB400)、500℃(RB500)和添加玉米秸秆炭300℃(CB300)、400℃(CB400)、500℃(CB500)。【结果】物料类型和制备温度因素显著影响裂解得到生物炭材料的养分含量和化学性质。培育试验表明,两种秸秆生物炭的添加,平均提高土壤p H值0.16个单位;土壤有机碳、速效磷和速效钾水平,分别比对照增加26.1%、20.6%和281.8%。水稻秸秆炭对土壤速效钾水平促进作用较大,而玉米秸秆炭则主要增加速效磷含量。低温裂解秸秆炭(300℃)的添加,并没有显著影响土壤碱解氮和无机氮含量;而添加RB500和CB500处理的碱解氮分别比对照低10.4%和8.1%,硝态氮含量分别比对照高63.6%和100.7%(P<0.05)。添加生物炭处理,微生物生物量碳和磷脂脂肪酸总量平均比对照增加63.4%和47.5%,但添加300℃秸秆炭处理与对照差异不显著;两种秸秆炭的输入均可以增加革兰氏阴性细菌(G-)、革兰氏阳性细菌(G+)、放线菌和真菌的含量,且不同制备温度处理间的差异表现为300℃<400℃<500℃。主成分分析表明,水稻秸秆炭对土壤微生物群落结构的影响较玉米秸秆炭更为显著;不同温度水稻秸秆炭间,群落结构差异明显,而不同温度玉米秸秆炭间没有区分开来。典范对应分析结果表明,生物炭添加可以通过改变土壤性质,间接影响微生物群落结构;其中,土壤速效磷、有机碳和速效钾含量与土壤微生物群落分布显著相关。【结论】水稻和玉米秸秆炭均可以改良红壤性水稻土的酸度,提高土壤养分含量和微生物量水平;两种秸秆炭的添加均改变了土壤微生物群落结构,其中以水稻秸秆炭的影响更为明显。
[Objective]The various effects of different straw biochar on nutrient content and microbial community structure were studied in order to provide information for soil amelioration and proper management of straw residue.[Method]Through a 135-day laboratory incubation experiment and used a red paddy soil that originated from the Quaternary, the influences of rice and corn straw biochar that pyrolyzed at 300℃, 400℃ and 500℃ on soil pH, organic carbon, nutrient content, microbial biomasscarbon and profile of microbial PLFAs community structure were investigated. The experiment consisted of seven treatments： control soil （CK）, soil amended with 300℃ （RB300）, 400℃ （RB400） and 500℃ （RB500） rice straw biochar, soil incorporated with 300℃（CB300）, 400℃ （CB400） and 500℃ （CB500） corn straw biochar. [Result] Feedstock type and pyrolysis temperature had a significant influence on the nutrient contents and chemical properties of biochar products. Compared with control, the two straw biochar amendments increased pH value by 0.16 unit and enhanced the contents of soil organic carbon, available P and available K by 26.1%, 20.6% and 281.8%, respectively. Under the same pyrolysis temperature, the application of rice straw biochar mainly promoted the level of available K while corn straw biochar improved the content of available P. Application of 300℃ straw biochar had no significant effect on soil available and mineral N contents. Compared with the control, soils amended with RB500 and CB500 were, respectively, 10.4% and 8.1% less in available N, while significantly increased by 63.6% and 100.7% in NO3--N concentration. Although the concentrations of microbial biomass carbon and total phospholipid fatty acids for soils amended with straw biochar were 63.4% and 47.5% higher than control soil, there was no significant difference between the control soil and soils with 300℃straw biochar. Both the two types of biochar enhanced the contents of G-, G＋, fungi and actinobacteria and shown as 300℃〈400℃〈500℃. Results of PCA indicated that rice straw biochar amendment had more effect on the structure of soil microbial community than corn straw biochar. The microbial community compositions of three rice straw biochar were separated from each other while no distinctive recognized among the three corn biochar. Results of CCA suggested that straw biochars can affect the composition of microbial community through altering soil chemical and nutrient properties, as soil available P, soil organic carbon and available had significant correlation with the distribution of soil microbial community. [Conclusion] Both the two straw biochars could ameliorate the acidity and nutrient content of red paddy soil, and enhance the level of soil microbial biomass. Soil microbial community structure had been affected in the presence of straw biochars and rice straw biochar had more effective influence than corn straw biochars.
出处
《中国农业科学》
CAS
CSCD
北大核心
2015年第7期1361-1369,共9页
Scientia Agricultura Sinica
基金
国家自然科学基金(41171233)
关键词
秸秆生物炭
土壤养分
微生物生物量碳
磷脂脂肪酸
典范对应分析
straw biochar
soil nutrient
microbial biomass carbon
phospholipid fatty acids
canonical correspondence analysis
