摘要
施NPK肥是提高人工林土壤肥力的有效措施之一,生物炭作为土壤改良剂,可以改良土壤物理性质,与有机肥同施有利于土壤保持养分;同时,施用生物炭被认为是缓解全球气候变暖的重要途径之一,因此受到关注。然而,关于这些不同施肥方式对土壤微生物群落碳源代谢及生态安全的影响和机制还缺乏了解。本试验以苏北沿海杨树人工林为试验基地,应用4种不同的施肥方式,即CK(对照组)、T1(NPK肥)、T2(NPK肥+生物炭)、T3(高浓度生物炭),分析不同施肥处理对土壤微生物在不同碳源利用方面的差异,以及施用生物炭是否影响土壤微生物代谢活性和碳源代谢多样性。结果表明:不同施肥方式土壤微生物代谢活性大小表现为:T3>T2>T1>CK,其中T3与CK差异显著,表明高浓度生物炭能显著提高土壤微生物代谢活性。微生物碳源利用多样性指数表现为:T3>T2>T1和CK,其中仅有Mc Intosh指数T3显著高于CK,在对6类碳源中的聚合物的利用上,T3显著高于CK,表明高浓度的生物炭添加会促进喜食聚合物的微生物群落生长,并具有改变土壤微生物多样性的潜力。主成分分析结果表明,增加主成分个数能够更有效地表达完整的信息,不同施肥方式在碳源利用上差异不明显,表明微生物群落功能稳定,短期施肥没有改变微生物碳源代谢多样性,而生物炭虽然可以显著提高土壤微生物代谢活性,但并没有显著改变其碳源代谢多样性。
Applying NPK iertlhzer is an et^tecnve way to improve Meanwhile, bio- char as good soil amendment has been shown to help soil keep fertility when it is used with organ- ic fertilizer and has received attention as a means to mitigate climate change. However, the un- derstanding of impact and mechanism of those different fertilizers on carbon metabolism and eco- logical security of soil microbes was very limited. With a poplar plantation in the coastal area of northern Jiangsu as the experimental site, we designed four fertilization treatments, CK （control group）, T1 （ NPK fertilizers）, T2 （ biochar＋NPK fertilizers）, T3 （ high level bioehar）, and an- alyzed the difference in utilizing different carbon sources under different fertilization treatments, to learn whether biochar would cause changes in soil microbial metabolic activity and carbon source metabolism. Our result showed that soil microbial metabolic activity was in order of T3 〉T2 〉TI〉CK, and T3 was significantly higher than CK, indicating high level bioehar might improve soil microbial metabolic activity significantly. The diversity indexes of microbial carbon source uti- lization were in order of T3〉T2〉T1 and CK. Only for the McIntosh index, T3 was significantly higher than CK. In the utilization of six groups of polymers, T3 was higher than CK, which indi- cated that biochar improved the population of microbes that was in favor of polymer utilization, and it also has the potential to change soil microbial functional diversity. Principal component analysis showed that the increase of the number of components in PCA presented information in a more effective way. Meanwhile, the differences in carbon utilization among the different fertiliza- tion regimes were not obvious, which indicated that the functioning of soil microbial community was stable and hard to be changed by short-term fertilization. Although biochar can improve soil microbial metabolic activity, it is unable to change the functional diversity of the microbes.soil f
出处
《生态学杂志》
CAS
CSCD
北大核心
2015年第7期1791-1797,共7页
Chinese Journal of Ecology
基金
国家重点基础研究发展计划项目(2012CB416904)
江苏生物学优势学科建设(PAPD)
江苏省自然科学基金青年专项(BK20130974)资助
关键词
施肥
生物炭
土壤微生物
BIOLOG
碳源利用
fertilization
biochar
soil microbe
Biolog
utilization of carbon sources.
