Institute for Resources, Environment and Sustainability, University of British Columbia, 2202 Main Mall, Vancouver, British Columbia, V6T 1Z4, Canada.
Institute for Resources, Environment and Sustainability, University of British Columbia, 2202 Main Mall, Vancouver, British Columbia, V6T 1Z4, Canada; Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC, Canada.
J Environ Manage. 2018 Apr 1;211:256-268. doi: 10.1016/j.jenvman.2017.12.052. Epub 2018 Feb 4.
Dissolved organic carbon (DOC) leached from Brazilian Cerrado Arenosols can lead to carbon (C) losses and lower soil fertility, while excessive nutrient, e.g. nitrate (NO), leaching can potentially cause water contamination. As biochar has been shown to stabilize C and retain soil nutrients, a greenhouse experiment was conducted to test different biochars' contributions to DOC and NO leaching from a sandy soil. Biochars were made from four local agricultural waste feedstocks (cotton residue, swine manure, eucalyptus sawmill residue, sugarcane filtercake) pyrolysed at 400, 500 and 600 °C. Biochar was mixed with soil at 5% weight in pots and maize seeds planted. Leachate was collected weekly for six weeks and analyzed for DOC and NO concentrations, while fluorescence spectroscopy with parallel factor analysis (PARAFAC) was used to interpret DOC characteristics. Cotton and swine manure biochar treatments had higher DOC and NO losses than eucalyptus biochar, filtercake biochar, and control treatments. Cotton and swine manure biochar treatments at high temperatures lost mostly terrestrial, humified DOC, while swine manure, filtercake, and eucalyptus biochars at low temperatures lost mostly labile, microbially-derived DOC. Through the practical use of fluorescence spectroscopy, our study identified filtercake and eucalyptus biochars as most promising for retaining DOC and NO in a Cerrado Arenosol, potentially reducing stable C and nutrient losses.
巴西塞拉多砂壤土淋溶出的溶解有机碳（DOC）可导致碳（C）损失和土壤肥力下降，而过量的养分（如硝酸盐（NO））淋溶可能会导致水污染。由于生物炭已被证明可以稳定 C 并保留土壤养分，因此进行了一项温室实验，以测试来自砂壤土的不同生物炭对 DOC 和 NO 淋溶的贡献。生物炭是由四种当地农业废弃物原料（棉花残渣、猪粪、桉树锯末、甘蔗滤饼）在 400、500 和 600°C 热解制成的。生物炭以 5%的重量与土壤混合在盆中，并种植玉米种子。每周收集一次渗滤液，分析 DOC 和 NO 浓度，同时使用平行因子分析（PARAFAC）荧光光谱法来解释 DOC 特征。棉花和猪粪生物炭处理的 DOC 和 NO 损失高于桉树生物炭、滤饼生物炭和对照处理。高温下的棉花和猪粪生物炭处理主要损失陆地、腐殖化的 DOC，而低温下的猪粪、滤饼和桉树生物炭主要损失易生物降解、微生物衍生的 DOC。通过荧光光谱法的实际应用，我们的研究确定滤饼和桉树生物炭在保留塞拉多砂壤土中的 DOC 和 NO 方面最有前景，可能会减少稳定 C 和养分的损失。
