Impact of biochar and manure application on in situ carbon dioxide flux, microbial activity, and carbon budget in degraded cropland soil of southern India
Impact of biochar and manure application on in situ carbon dioxide flux, microbial activity, and carbon budget in degraded cropland soil of southern India
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DOI：
10.1002/ldr.4234
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发表时间：
2022-02
影响因子：
4.7
通讯作者：
Mayuko Seki;S. Sugihara;Hidetoshi Miyazaki;M. Jegadeesan;P. Kannan;I. Bertrand;Haruo Tanaka
中科院分区：
文献类型：
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作者：
Mayuko Seki;S. Sugihara;Hidetoshi Miyazaki;M. Jegadeesan;P. Kannan;I. Bertrand;Haruo Tanaka
生物炭的应用是防止土地退化的一种有效的土壤有机碳(SOC)管理方法，但其对二氧化碳(CO2)通量和相关微生物响应的影响的定量信息仍然很少，特别是在退化的热带农业生态系统中。我们进行了为期27个月的田间试验，定期测量环境因素、二氧化碳外排速率、微生物生物量C(MBc)和SOC存量，并评估土地管理(对照(C)、生物炭(B；8.2mgC ha−1)、农家肥(FYM)(M；1.1mgC ha−1年−1))以及两者的混合物(BM)对印度南部热带碱性农田二氧化碳通量、微生物响应(微生物活性)和碳收支的影响。根据二氧化碳外排速率与环境因子之间的关系，估算了C、B、M和BM处理的累积二氧化碳通量分别为2.4、2.7、4.0和3.7mgCha−1。生物炭的应用增加了土壤水分，但不影响二氧化碳通量，导致了正的碳收支(6.7mgC ha−1)，这是因为微生物对土壤水分增加的反应有限，因为微生物对土壤水分的反应很少。生物炭和FYM配合使用并没有增加CO2通量，而是增加了最大的有机碳增量(8.9mgC ha−1)和正的碳收支(9.1mgC ha−1)，这是因为两个处理之间的微生物响应差异不大。因此，在印度南部退化的农田中，生物炭结合FYM可能是一种有效的SOC管理方法。
Biochar application is attracting attention to be an effective soil organic carbon (SOC) management to prevent land degradation, though quantitative information of its effect on carbon dioxide (CO2) flux and associated microbial responses is still scarce, especially in degraded tropical agroecosystems. We conducted a 27‐month field experiment with periodically measuring environmental factors, CO2 efflux rate, microbial biomass C (MBC), and SOC stock, and evaluated the impact of land management (control (C), biochar (B; 8.2 Mg C ha−1), farmyard manure (FYM) (M; 1.1 Mg C ha−1 yr−1), and a mixture of both (BM) on CO2 flux, microbial responses (MBC and qCO2 as microbial activity) and C budget, in tropical alkaline cropland of southern India. Based on the relationship between the CO2 efflux rate and environmental factors, cumulative CO2 flux was estimated at 2.4, 2.7, 4.0, and 3.7 Mg C ha−1 in the C, B, M, and BM treatments, respectively. Biochar application increased soil moisture though did not affect CO2 flux, causing a positive C budget (6.7 Mg C ha−1), because of the limited response of microbes to increased soil moisture due to the small amount of SOC. Biochar and FYM combined application did not increase CO2 flux compared with FYM alone, contributing to the largest SOC increment (8.9 Mg C ha−1) with a positive C budget (9.1 Mg C ha−1), due to little difference of microbial responses between the two treatments. Hence, biochar application combined with FYM could be an effective SOC management in the degraded cropland of southern India.