分层旋耕对稻茬麦生长与土壤物理的影响研究

发布时间：2018-02-23 01:24

本文关键词： 分层旋耕小麦根系土壤物理性状水稻土自幂　出处：《南京农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：我国南方水稻土的类型多、面积大、分布广,但多数土地的产出较低,其原因之一在于长期浅旋耕作导致水田耕层变浅、犁底层变厚、土壤耕性变差,常规的深松机在水稻土条件很难达到预期的土壤破碎效果。水稻土耕性不良、破碎效果差等状况为研发新型耕作技术提出了挑战,前人结合分层耕作的优势研发了分层旋耕切土机等机型,本文对分层旋耕的进行技术论证,通过对比免耕、常规旋耕与分层旋耕分别对小麦根系生长、物理性状与土壤自幂的影响,为稻茬麦增产增收提出一种新型耕作措施。本文首先通过挖掘与旋耕方式人工模拟出分层旋耕耕作、常规旋耕与免耕,通过研究耕作方式对小麦的根系抗拉强度、根系活力、根系构型、根重以及小麦产量等的影响,进而对不同的耕作措施进行评价,从实践中验证分层旋耕是否可行,对小麦根系性状以及产量较其他两种耕作方式是否有着明显的影响。结果表明:(1)经过分层旋耕后的小麦的根系性状均优于免耕与常规旋耕,其中根系抗拉强度分别提高了14.07%与-6.52%、根系条数分别增加了14.77%与10.19%、根系活力提高了16.46%与12.20%、分层旋耕后的根系下扎深度能达到280mm高于免耕与常规旋耕、根重分别增加了 68.79%与36.14%;(2)分层旋耕的小麦产量均比免耕与常规旋耕提高10.69%与15.41%。为更好、更便捷地模拟出分层旋耕耕作模式,构建了分层旋耕实验平台,将平台运用于田间试验进行真实的农田环境实现分层旋耕模式。在麦季期间对不同的土壤物理性状进行连续测试,反映出南方水稻土条件下的不同耕作措施对土壤环境的影响。实验结果表明:分层旋耕与免耕和常规旋耕相比,耕层持水量分别提高了1.47%与0.3%、土壤容重分别降低了0.11Mg/m3与0.07Mg/m3、增加了耕作层深度约1Ocm,土壤含水率分别提高了6.78%和7.04%、耕作层贯入阻力分别降低了43.19%和27.65%,孔隙度分别提高了0.05%与0.01%,并且改善了土壤三相比等。影响土壤物理性状的因素不仅包括机械耕作、作物轮作制度、土壤生物,还包括气候条件。气候条件最直接的表现是通过土壤自幂行为,改变表层土壤物理性状。本文通过对比耕作与免耕对麦季前后土壤自幂情况,从而证明耕作对自幂的影响。结果表明:麦季过后,在0-40mm表层内常规旋耕比免耕提高团聚体含量122.72%,内摩擦角降低了16.10%。
[Abstract]:There are many types, large area and wide distribution of paddy soil in the south of China, but the output of most of the land is low. One of the reasons is that the tilling layer becomes shallow, the plow bottom becomes thicker, and the soil tillage becomes poor because of the long term shallow rotation tillage. It is very difficult for conventional deep loosening machine to achieve the expected soil crushing effect in paddy soil conditions. The poor tillage and crushing effect of paddy soil pose a challenge to the research and development of new tillage technology. According to the advantages of stratified tillage, the former developed the layered rotary tillage and soil cutting machine. The technology of stratified rotary tillage was demonstrated in this paper. Through the comparison of no-tillage, conventional rotary tillage and stratified rotary tillage, wheat roots were grown, respectively. In this paper, a new tillage method was proposed to increase the yield and income of rice stubble wheat by the influence of physical properties and soil self-power. Firstly, stratified rotary tillage, conventional rotary tillage and no-tillage were simulated by digging and rotary tillage. The effects of tillage methods on wheat root tensile strength, root activity, root configuration, root weight and wheat yield were studied, and different tillage measures were evaluated to verify the feasibility of stratified rotary tillage. The results showed that the root characters of wheat after stratified rotary tillage were better than those of no-tillage and conventional rotary tillage. The tensile strength of roots increased by 14.07% and -6.52, the number of root strips increased by 14.77% and 10.19, and the root activity increased by 16.46% and 12.20 respectively. The root root depth after stratified rotary tillage was 280mm higher than that of no-tillage and conventional rotary tillage. The root weight increased by 68.79% and 36.14 respectively. The yield of wheat in stratified rotary tillage was 10.69% and 15.41 higher than that of no-tillage and conventional rotary tillage, respectively. In order to better and more conveniently simulate the stratified rotary tillage model, the experimental platform of stratified rotary tillage was constructed. The platform was applied to the field experiment to realize the stratified rotary tillage model. Different soil physical properties were continuously tested during wheat season. The results showed that the effect of different tillage measures on soil environment was compared with that of no-tillage and conventional rotary tillage. The soil bulk density decreased by 0.11mg / m3 and 0.07mg / m3, increased the depth of tilling layer by about 1 Ocm, increased soil moisture content by 6.78% and 7.04, decreased the penetration resistance of tilling layer by 43.19% and 27.65, and increased porosity, respectively. 0.05% and 0.01, and improved soil three. The factors that affect soil physical properties include not only mechanical farming, Crop rotation system, soil organisms, and climate conditions. The most direct manifestation of climatic conditions is to change the physical properties of surface soil through soil self-power behavior. In this paper, the self-power of soil before and after wheat season is compared with that of no-tillage. The results showed that after wheat season, conventional rotary tillage increased the aggregate content by 122.72% and the angle of internal friction decreased by 16.10% compared with no-tillage in 0-40mm surface layer after wheat season.
【学位授予单位】：南京农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S512.1;S152

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