黏质红壤干旱和穿透阻力对玉米作物水分关系的影响
发布时间：2018-08-02 19:28
【摘要】：季节性干旱是黏质红壤地区农业生产的主要限制因素之一。对于黏质红壤,随着含水量降低,土壤穿透阻力随之增加,影响作物根系生长和分布,改变吸收水分和养分的能力,从而也影响作物的根叶水势等水分关系。干旱胁迫和阻力胁迫对作物的影响错综复杂,但关于干旱过程中土壤穿透阻力对作物影响的研究较少,二者的共同作用尚不清楚。本文研究黏质红壤不同干旱程度下,穿透阻力对玉米作物水分关系的影响,为防治红壤地区季节性干旱提供理论依据。本文的田间试验在位于湖北咸宁的红壤试验站内进行,于2014-2015年的6-10月进行两季玉米小区试验。试验设置了4个耕作处理(深耕D、常规耕作C、免耕N和压实P),以得到不同的穿透阻力;从玉米8叶期开始,每个耕作处理分别设置3个干旱水平,即不干旱(每星期灌水12 mm,共灌水72 mm)、轻度干旱(共灌水24 mm)和严重干旱(不灌水)。田间小区土壤为第四纪红色黏土发育的红壤,种植的玉米品种为郑单958。在玉米12叶期、16叶期、抽穗期分别测定土壤穿透阻力、土壤含水量、根叶水势、气孔导度与净光合速率等,每个处理重复三次,玉米收获后考种,得到以下研究结果:1)土壤含水量和穿透阻力在土壤剖面分布上具有一定的规律性。土壤含水量随深度增加而显著增加,而土壤穿透阻力呈先增加后降低的趋势,在20 cm处达到峰值,严重干旱处理下压实的阻力最大达到2.797 MPa。不干旱条件下,各耕作处理间含水量和穿透阻力的差异较小,随着干旱程度的增加,耕作处理间的差异变大。穿透阻力随含水量的升高而降低,两者呈非线性负相关(P0.05),但当土壤含水量处在较高水平(0.24 g/g),土壤穿透阻力到达一个临界点(0.5~0.6MPa)而趋于平稳,说明不干旱的红壤也具有较高的穿透阻力,这与黏质红壤特性有关。2)玉米根叶水势以及净光合速率等与土壤含水量和基质势呈显著正相关,而与穿透阻力呈显著负相关。耕作处理间的土壤含水量与根叶水势和净光合速率等的关系有明显的差异,从大到小的顺序为DCNP,与土壤穿透阻力大小顺序相反,随着干旱程度增加,耕作处理间的差异变大。干旱和耕作对作物根叶水势和净光合速率等的影响达到极显著(P0.01),同时干旱和耕作对根叶水势等表现出显著的交互作用(P0.05)。回归分析表明,在不干旱处理下,土壤穿透阻力的回归系数大于含水量的系数,说明此时穿透阻力对根叶水势等的影响大于含水量。而随着干旱程度的增加,穿透阻力增加,由方差分析结果可知,干旱和阻力共同影响作物水分关系,此时干旱对玉米根叶水势等水分关系的影响更大。3)红壤干旱和穿透阻力影响玉米根系的分布。在轻度干旱下,玉米根系的分布范围有所增加;而在严重干旱时,根系的垂直和水平分布范围均减小。在土层深度20-40 cm范围内,深耕比常规耕作、免耕和压实分别高-0.23%、15.13%和160%。在10-15cm范围内,深耕比常规耕作、免耕和压实分别高30.40%、44.13%和53.45%。说明耕作(穿透阻力)可以调控根系水平和垂直分布。4)土壤干旱和穿透阻力对玉米产量的影响都达到了极显著,两者的交互作用达到了显著水平,说明穿透阻力促进作物干旱致灾,而耕作能有效调控干旱和作物产量的关系。土壤含水量和基质势与玉米产量呈显著正相关,而土壤穿透阻力与玉米的产量呈负相关。不同干旱水平下作物产量总体顺序均为DCNP,随着干旱程度的增加,耕作处理间的差异变大。回归分析表明,在不干旱处理下阻力的系数大于含水量的系数,说明此时穿透阻力对作物产量的影响大于含水量;而随着干旱程度增加,土壤含水量降低,穿透阻力急剧增加,由方差分析可知,干旱和阻力共同影响玉米产量,此时干旱对玉米产量的影响更大。黏质红壤在不干旱条件下,玉米作物表现阻力胁迫;随着干旱程度增加,水分胁迫的影响大于阻力胁迫,是红壤季节性干旱致灾的重要原因。耕作措施可同时显著改变黏质穿透阻力和水分状况,其中免耕对作物水分关系有明显的副作用,而深耕能够明显降低土壤穿透阻力,调控作物水分关系效果明显。
[Abstract]:Seasonal drought is one of the main restrictive factors for agricultural production in clay red soil. With the decrease of water content, the penetration resistance of soil increases with the decrease of water content, the growth and distribution of crop roots, the ability to absorb water and nutrients, and the water relationship of the root and leaf water potential of the crops. Drought stress and resistance stress are also affected. The impact on crops is complex, but the study of soil penetration resistance in the course of drought is less. The effect of the two is not clear. This paper studies the influence of penetration resistance on the water relationship of corn crop under different degree of drought in clay red soil. This paper provides a theoretical basis for the prevention and control of seasonal drought in red soil. Field trials were carried out in the red soil test station in Xianning, Hubei, in the two quarter of 6-10 months of 2014-2015 years. 4 tillage treatments (deep ploughing D, conventional tillage, no tillage N and compacted P) were set up to obtain different penetration resistance. From the beginning of the 8 leaf period of corn, 3 drought levels were set in each tillage treatment, that is, Drought (12 mm per week irrigation, 72 mm in total water), mild drought (total irrigation 24 mm) and severe drought (no irrigation). The soil in the field is red soil developed in the Quaternary red clay. The cultivated maize varieties are Zhengdan 958. at 12 leaf stage and 16 leaf stage, and the soil water content, root leaf water potential and stomatal conductance of soil water content, root leaf water potential, and leaf water potential respectively. With net photosynthetic rate, each treatment was repeated three times, after maize harvest test, the following results were obtained: 1) soil moisture content and penetration resistance have certain regularity in soil profile distribution. Soil water content increased significantly with depth, and soil penetration resistance increased first and then decreased, reaching a peak at 20 cm. Under the condition of severe drought, the maximum resistance to compaction reached 2.797 MPa.. The difference of water content and penetration resistance between different tillage treatments was smaller. With the increase of the degree of drought, the difference between the tillage treatments became larger. The penetration resistance decreased with the increase of water content, and the difference was nonlinear negative correlation (P0.05), but when the soil water content was in the soil, The higher level (0.24 g/g), soil penetration resistance reached a critical point (0.5~0.6MPa) and tended to be stable, indicating that the unarid red soil also had higher penetration resistance, which was related to the characteristics of the clay red soil. The root leaf water potential and net photosynthetic rate of maize were significantly positively correlated with soil water content and matrix potential, but significantly negative to penetration resistance. The relationship between soil water content and root leaf water potential and net photosynthetic rate was significantly different. The order from large to small was DCNP, which was opposite to the order of soil penetration resistance. The effect of drought and tillage on the root leaf water potential and net photosynthetic rate of crops increased with the increase of soil penetration resistance. The regression analysis showed that the regression coefficient of soil penetration resistance was greater than the coefficient of water content in the non drought treatment, indicating that the penetration resistance had greater influence on the root and leaf water potential than the water content, but with the increase of drought, the regression analysis showed that the influence of penetration resistance on the water potential of root and leaf was greater than water content. Through the analysis of variance, the results of variance analysis showed that drought and resistance had a common influence on the relationship between crop water and water. At this time, the effect of drought on the water relationship of maize root and leaf water potential was more.3). The drought and penetration resistance of red soil affected the distribution of maize root system. In the range of 20-40 cm soil depth, deep tillage is higher than conventional tillage, no tillage and compaction by -0.23%, 15.13% and 160%. in the 10-15cm range. Deep tillage is 30.40% higher than conventional tillage, no tillage and compaction are higher, 44.13% and 53.45%., respectively, to indicate that tillage (penetration resistance) can regulate root level and vertical distribution of.4). The effect of soil drought and penetration resistance on the yield of maize reached a very significant level. The interaction of the two has reached a significant level, which indicates that the penetration resistance promotes the drought caused by the crop, and the cultivation can effectively regulate the relationship between drought and crop yield. The yield of maize was negatively correlated. The overall order of crop yield under different drought levels was DCNP. With the increase of drought, the difference between the tillage treatment was larger. The regression analysis showed that the coefficient of resistance was greater than the water content, which indicated that the penetration resistance had greater influence on the crop yield than the water content. With the increase of drought, the water content of soil decreased and the penetration resistance increased sharply. By the analysis of variance analysis, drought and resistance had a common effect on maize yield. At this time, the effect of drought on maize yield was greater. Under the condition of non drought, the corn crop showed resistance stress; with the increase of drought, the effect of water stress was greater than that of resistance stress. It is an important cause of the seasonal drought in red soil. The tillage measures can also significantly change the penetration resistance and water condition of the clay. The no tillage has obvious side effects on the water relationship of crops, while deep tillage can obviously reduce the penetration resistance of the soil, and the effect of regulating the water relationship of the crops is obvious.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S513;S423
本文编号：2160490
[Abstract]:Seasonal drought is one of the main restrictive factors for agricultural production in clay red soil. With the decrease of water content, the penetration resistance of soil increases with the decrease of water content, the growth and distribution of crop roots, the ability to absorb water and nutrients, and the water relationship of the root and leaf water potential of the crops. Drought stress and resistance stress are also affected. The impact on crops is complex, but the study of soil penetration resistance in the course of drought is less. The effect of the two is not clear. This paper studies the influence of penetration resistance on the water relationship of corn crop under different degree of drought in clay red soil. This paper provides a theoretical basis for the prevention and control of seasonal drought in red soil. Field trials were carried out in the red soil test station in Xianning, Hubei, in the two quarter of 6-10 months of 2014-2015 years. 4 tillage treatments (deep ploughing D, conventional tillage, no tillage N and compacted P) were set up to obtain different penetration resistance. From the beginning of the 8 leaf period of corn, 3 drought levels were set in each tillage treatment, that is, Drought (12 mm per week irrigation, 72 mm in total water), mild drought (total irrigation 24 mm) and severe drought (no irrigation). The soil in the field is red soil developed in the Quaternary red clay. The cultivated maize varieties are Zhengdan 958. at 12 leaf stage and 16 leaf stage, and the soil water content, root leaf water potential and stomatal conductance of soil water content, root leaf water potential, and leaf water potential respectively. With net photosynthetic rate, each treatment was repeated three times, after maize harvest test, the following results were obtained: 1) soil moisture content and penetration resistance have certain regularity in soil profile distribution. Soil water content increased significantly with depth, and soil penetration resistance increased first and then decreased, reaching a peak at 20 cm. Under the condition of severe drought, the maximum resistance to compaction reached 2.797 MPa.. The difference of water content and penetration resistance between different tillage treatments was smaller. With the increase of the degree of drought, the difference between the tillage treatments became larger. The penetration resistance decreased with the increase of water content, and the difference was nonlinear negative correlation (P0.05), but when the soil water content was in the soil, The higher level (0.24 g/g), soil penetration resistance reached a critical point (0.5~0.6MPa) and tended to be stable, indicating that the unarid red soil also had higher penetration resistance, which was related to the characteristics of the clay red soil. The root leaf water potential and net photosynthetic rate of maize were significantly positively correlated with soil water content and matrix potential, but significantly negative to penetration resistance. The relationship between soil water content and root leaf water potential and net photosynthetic rate was significantly different. The order from large to small was DCNP, which was opposite to the order of soil penetration resistance. The effect of drought and tillage on the root leaf water potential and net photosynthetic rate of crops increased with the increase of soil penetration resistance. The regression analysis showed that the regression coefficient of soil penetration resistance was greater than the coefficient of water content in the non drought treatment, indicating that the penetration resistance had greater influence on the root and leaf water potential than the water content, but with the increase of drought, the regression analysis showed that the influence of penetration resistance on the water potential of root and leaf was greater than water content. Through the analysis of variance, the results of variance analysis showed that drought and resistance had a common influence on the relationship between crop water and water. At this time, the effect of drought on the water relationship of maize root and leaf water potential was more.3). The drought and penetration resistance of red soil affected the distribution of maize root system. In the range of 20-40 cm soil depth, deep tillage is higher than conventional tillage, no tillage and compaction by -0.23%, 15.13% and 160%. in the 10-15cm range. Deep tillage is 30.40% higher than conventional tillage, no tillage and compaction are higher, 44.13% and 53.45%., respectively, to indicate that tillage (penetration resistance) can regulate root level and vertical distribution of.4). The effect of soil drought and penetration resistance on the yield of maize reached a very significant level. The interaction of the two has reached a significant level, which indicates that the penetration resistance promotes the drought caused by the crop, and the cultivation can effectively regulate the relationship between drought and crop yield. The yield of maize was negatively correlated. The overall order of crop yield under different drought levels was DCNP. With the increase of drought, the difference between the tillage treatment was larger. The regression analysis showed that the coefficient of resistance was greater than the water content, which indicated that the penetration resistance had greater influence on the crop yield than the water content. With the increase of drought, the water content of soil decreased and the penetration resistance increased sharply. By the analysis of variance analysis, drought and resistance had a common effect on maize yield. At this time, the effect of drought on maize yield was greater. Under the condition of non drought, the corn crop showed resistance stress; with the increase of drought, the effect of water stress was greater than that of resistance stress. It is an important cause of the seasonal drought in red soil. The tillage measures can also significantly change the penetration resistance and water condition of the clay. The no tillage has obvious side effects on the water relationship of crops, while deep tillage can obviously reduce the penetration resistance of the soil, and the effect of regulating the water relationship of the crops is obvious.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S513;S423
【参考文献】
相关期刊论文 前2条
1 王丁;姚健;杨雪;薛建辉;;干旱胁迫条件下6种喀斯特主要造林树种苗木叶片水势及吸水潜能变化[J];生态学报;2011年08期
2 齐健;宋凤斌;刘胜群;;苗期玉米根叶对干旱胁迫的生理响应[J];生态环境;2006年06期
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