Center of Biomass and Biochar Green Technology, Institute of Resource, Ecosystem and Environment of Agriculture, Nanjing Agricultural University, 1 Weigang, Nanjing, 210095, China.
Sci Rep. 2018 Jan 16;8(1):802. doi: 10.1038/s41598-018-19331-z.
The role of extractable pool of biochar in crop productivity and soil greenhouse gas (GHGs) emission is not yet clear. In this study, two biochars with and without extraction was added to a paddy before rice transplantation at 20 t·ha. Crop yield, plant traits and greenhouse gas emission monitored throughout a rice-wheat rotation. Between the biochar treatments, changes in bulk density and microbial biomass carbon were insignificant. However, the increase in organic carbon was similar between maize and wheat biochars while higher under bulk wheat biochar than extracted one. The increase in available P and K was higher under wheat than maize biochar regardless of extraction. Moreover, the increase in plant traits and grain yield, in rice season only, was higher under bulk than extracted biochars. Yet, there was no difference in changes in GHGs emission between bulk and extracted biochars regardless of feedstock. Nevertheless, increased methane emission for rice season was lower under extracted biochars than bulk ones. Overall, crop productivity rather than GHGs emission was affected by treatment of extraction of biochars. Thus, use of unextracted biochar is recommended for improving soil crop productivity in the paddy soils.
生物炭可提取池在作物生产力和土壤温室气体（GHG）排放中的作用尚不清楚。本研究在水稻移栽前，向稻田中添加了 20 t·ha 的具有和不具有提取功能的两种生物炭。在水稻-小麦轮作期间监测了作物产量、植物特性和温室气体排放。在生物炭处理之间，体积密度和微生物生物量碳的变化不显著。然而，玉米和小麦生物炭之间的有机碳增加相似，而整粒小麦生物炭的增加高于提取的生物炭。无论提取与否，小麦生物炭的有效 P 和 K 增加均高于玉米生物炭。此外，仅在水稻季节，整粒生物炭下植物特性和籽粒产量的增加高于提取的生物炭。然而，无论原料如何，生物炭的大块和提取对温室气体排放的变化均无差异。尽管如此，与整粒生物炭相比，提取生物炭下水稻季节的甲烷排放较低。总体而言，生物炭的提取处理影响作物生产力而不是温室气体排放。因此，建议在稻田中使用未提取的生物炭来提高土壤作物生产力。
