Li Chuan-Zhe, Zhang Huan, Yao Wen-Jing, Xu Cong, Wu Di, Wang Ji-Dong, Ai Yu-Chun, Zhang Yong-Chun
Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences/Ministry of Agriculture and Rural Affairs Scientific Observation and Experimental Station of Arable Land Conservation of Jiangsu Province, Nanjing 210014, China.
School of Agriculture Equipment Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
Ying Yong Sheng Tai Xue Bao. 2020 Oct;31(10):3424-3432. doi: 10.13287/j.1001-9332.202010.028.
The aims of this study were to reveal the effects of biochar application combined with nitrogen fertilizer on soil physicochemical properties and crop yield in the typical ancient region of Yellow River, and to clarify the dynamics of carbon and nitrogen content and soil physicochemical properties with different treatments of biochar and nitrogen, which could provide scientific basis for reasonable fertilization of soil, quality improvement of cultivated land, and yield increase of winter wheat. A two-year field experiment was conducted with different biochar applications (0, 15, 30 t·hm) combined with different nitrogen levels (N 270, 330 kg·hm) to investigate their effects on soil physicochemical property in the typical ancient of Yellow River. After 2-yr biochar application, the generalized soil structure index (GSSI) was increased and three-phase structure distance index of soil (STPSD) was decreased, and three-phase ratio was significantly improved. The most ideal state of three-phase ratio was in the condition of 30 t·hm biochar application. Soil compactness and bulk density was decreased, total porosity and capillary porosity was increased, water holding capacity was improved, water and gas permeability was enhanced, and soil hardening was relieved. The composition of soil aggregate was also changed. Soil aggregate >0.25 mm particle size was increased by 70.6%-94.4%, and mean weight diameter (MWD) was improved by 24.0%-48.0%. Biochar application significantly increased organic carbon content by 15.8%-67.0%, adjusted soil C/N, reduced nitrogen release intensity, improved utilization rate of nitrogen fertili-zer, and enhanced soil fertility. However, it didn't increase soil pH. Soil pH showed a significant downward in 10-20 cm layer. With the same amount of nitrogen application, biochar application significantly increased average yield of winter wheat by 9.6%-25.6% in two years. With the same amount of biochar application, average yield of winter wheat with high nitrogen application was 2.5%-4.4% higher than that with conventional nitrogen application. In summary, combined biochar and nitrogen application could improve soil micro-environment, soil fertility and crop yield. Comprehensively considering soil modification, crop yield improvement and input cost, the optimum amount of fertilization was biochar application (30 t·hm) combined with nitrogen fertilizer (330 kg·hm).
本研究旨在揭示在黄河典型古灌区施用生物炭与氮肥配施对土壤理化性质及作物产量的影响，阐明不同生物炭与氮肥处理下碳氮含量及土壤理化性质的动态变化，为土壤合理施肥、耕地质量提升及冬小麦增产提供科学依据。通过开展为期两年的田间试验，设置不同生物炭施用量（0、15、30 t·hm）与不同氮水平（N 270、330 kg·hm），研究其对黄河典型古灌区土壤理化性质的影响。施用生物炭两年后，土壤综合结构指数（GSSI）升高，土壤三相结构距离指数（STPSD）降低，三相比显著改善。三相比最理想的状态是在施用30 t·hm生物炭的条件下。土壤紧实度和容重降低，总孔隙度和毛管孔隙度增加，持水能力提高，水气渗透性增强，土壤板结得到缓解。土壤团聚体组成也发生了变化。土壤团聚体>0.25 mm粒径增加了70.6%-94.4%，平均重量直径（MWD）提高了24.0%-48.0%。施用生物炭显著提高了有机碳含量15.8%-67.0%，调节了土壤碳氮比，降低了氮素释放强度，提高了氮肥利用率，增强了土壤肥力。然而，它并未提高土壤pH值。土壤pH值在10-20 cm土层呈显著下降趋势。在施氮量相同的情况下，施用生物炭使冬小麦两年平均产量显著提高了9.6%-25.6%。在生物炭施用量相同的情况下，高氮处理的冬小麦平均产量比常规施氮处理高2.5%-4.4%。综上所述，生物炭与氮肥配施可改善土壤微环境、土壤肥力及作物产量。综合考虑土壤改良、作物增产及投入成本，最佳施肥量为生物炭施用（30 t·hm）与氮肥（330 kg·hm）配施。
