【作者】 张娜；

【导师】 廖允成；

【作者基本信息】 西北农林科技大学 ， 作物栽培学与耕作学， 2015， 硕士

【摘要】 生物炭是生物质在完全或部分缺氧条件下高温裂解形成的固态产物。近年来,生物炭作为土壤改良剂、肥料缓释载体以及碳汇剂,已成为国内外研究的热点。为更好的促进生物炭在农业上的应用,本研究立足于陕西关中塿土地区,以小麦秸秆生物炭为研究对象,基于夏玉米-冬小麦复种体系,通过设置不同生物炭施用量[0(CK)、1000 kg·hm-2(T1),5000 kg·hm-2(T2),10000 kg·hm-2(T3)],分析研究生物炭对作物生长、产量及塿土土壤理化性质的影响,探明本地区适宜的生物炭农田施用量,为生物炭在农业生产中的有效利用提供理论依据。本研究得到的主要结论如下:(1)不同量的生物炭施用均能显著提高夏玉米和冬小麦产量,其中夏玉米表现为T1增产幅度最大,比对照显著高8.8%,小麦表现为T2最大,比对照显著高9.9%;产量构成因素玉米表现为穗粒数T3显著高于T1和CK,百粒重表现为T1显著高于T3和CK,而小麦穗数、穗粒数和千粒重各处理间无显著差异性。生物炭显著影响叶面积指数、叶片净光合速率、叶绿素含量、干物质积累等指标,T2、T3处理能显著增加夏玉米和冬小麦地上部干物质量。在生长前期表现为高生物炭施用量更有利于叶面积指数的增加和光合速率的提高,但生长后期,较低量的生物炭施用更有利于夏玉米叶片的持绿和光合作用的持续,而较高量的生物炭施用下夏玉米植株有早衰迹象,在冬小麦后期表现不明显。(2)生物炭的施用对提高土壤含水量有一定的影响但作用不显著。在土壤水分含量较低的情况下,少量的生物炭能提高土壤含水量,而在土壤水分含量较为正常的情况下,施用生物炭反而有降低土壤含水量的趋势。其中,在玉米拔节期,CK高于其他处理,抽雄期,T3低于其他处理,灌浆期和成熟期T1高于其他处理;在小麦拔节期,CK高于其他处理,成熟期,30cm以上T1高于其他处理,30cm以下CK显著高于T2、T3。(3)生物炭的施入在不同程度上可改善土壤养分状况。与CK相比,添加生物炭均可提高土壤耕层土壤有机质含量。较高施炭量(T2、T3)对提高夏玉米耕层土壤碱解氮水平作用显著,而较低的生物炭施用(T1)反倒更有利于冬小麦耕层土壤碱解氮含量的提高。与CK相比,T2处理更能提高冬小麦耕层土壤速效磷含量,但对于夏玉米,生物炭施用无显著影响。生物炭的施用有利于耕层土壤速效钾含量的提高,对于夏玉米,T2表现较好,但对于冬小麦,土壤速效钾含量随生物炭施用量的增加而增加。更多还原

【Abstract】 Biochar is a kind of material produced by thermal decomposition of organic materials in anaerobic or anoxic conditions. In recent years, biochar has been drawing increasingly attentionboth at home and abroad as an important soil amendment, carbon sequestration agent and controlled-release carriers to fertilizer. In order to promotethe utilization of biochar in agriculture and prove suitable biochar content in Guanzhong Plainarea, and provide a theory basis for the biochar effective utilization in agricultural production, a field experimentwas conducted to study the effects of biochar application on crop growth, yield and soil physical and chemical properties in manural loessial soil of Guanzhong Plain area, Shaanxi Province, PR China. The experimentwas carried out in the randomly arranged blocks, with 5 treatments and 3 replications. The experimental treatments included 4 levels of biochar: no biochar(CK), 1 000 kg?hm-2(T1), 5 000 kg?hm-2(T2), 10 000 kg?hm-2(T3). Plant and soil samples were sampled at regular intervals during maize and wheat growing season(seedling/ tillering stage, jointing stage, heading stage, grain filling stage and maturing stage). The objective of the present study was to investigate the the effect of biochar on crop growth and soil physical and chemical properties, and explain the suitable amount of biochar applation at Guanzhong Plain.The results showed that all biochar application treatments significantly promotedgrain yield of summer maize and winter wheat. For summer maize,the T1 treatment had the highest grain yield in different treatments, and it was 8.8% higher than that of CK. While the highest yield of wheat is T2, it was 9.9% higher than CK. For summer maize, the kernel per spike of T3 was significantly higher than those of T1 and CK, however, the grain weight of T1 was significantly higher than that of T3 and CK. The spike number, kernel per spike and thousand kernel weight of wheat had no significant differences between treatments. The application of biochar notably affected the LAI, net photosynthetic rate, chlorophyll of leaves and the accumulation of shoot biomass. Especially, T2 and T3 could notably increase the shoot biomass of both wheat and summer maize. The higher biochar had higher LAI and net photosynthetic rate of leaves than the less biochar application at early growth stage. However, leaves in the less biochar level had photosynthesis for more days as compared with higher biochar levels at later growth stage of summer maize, and the higher biochar level treatment resulted premature senility, while, this phenomenon was not obvious at the later growth stage of wheat.Boichar has no significant influence on soil moisture content. Under the low level of water capacity of the field, moderate boichar could improve the soil moisture content, the water condition of the field was appropriate, biochar treatments would lead to a decline of the soil moisture content.Biochar could obviously improve the soil nutrient status. Compared with CK, biochar treatments could improve the organic matter content of soil. Higher boichar treatments(T2, T3) could significantly improve the level of available nitrogen content in arable layer soil of summer maize, but a lower biochar application(T1) was more beneficial to improve the available nitrogen content in wheat. Compared with CK, T2 treatment was likely to improve the available phosphorus content in wheat, but for summer maize, biochar application had no significant effect on the available phosphorus content. Biochar applications were beneficial to improve available potassium content in both summer maize and wheat growing season. For summer maize, T2 was better in all treatments, but for wheat, soil available potassium content increased with the increase of biochar usage.更多还原