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土壤遭受水淹后基本上停止了与大气间的气体交换并严重地阻碍氧气流进活性根系表面和土壤中微生物处。虽然大部分土壤空隙中的空气在水淹后被排除,但很少是全部排尽。水淹土壤中的空气存留量取决于土壤类型和渍水方式。实验室内即使用大气压力的浸渍方法来排除,砂壤土内总空隙的10%以上仍包含着空气。水淹土壤造成植株缺氧所需的时间取决于存留的空气量、植株根部和微生物的呼吸率、及氧气经过植株的通气部份向下的扩散。田间烟草可能因下雨过多而受淹,需要测定不同时间水淹的收回产量。
Submerged flooding of the soil essentially ceases gas exchange with the atmosphere and severely inhibits the flow of oxygen into the active root surfaces and soil microbes. Although most of the air in the soil void is excluded after flooding, it is seldom exhausted. The amount of air in the flooded soil depends on the soil type and the type of waterlogging. Even if the atmospheric pressure dipping method to exclude the laboratory, sandy loam more than 10% of the total space still contains air. The time required for flooding soil to cause plant hypoxia depends on the amount of air trapped, the respiration rate of plant roots and microorganisms, and the downward diffusion of oxygen through the plant’s aeration section. Field tobacco may be flooded due to excessive rains and the need to measure the recovery of flooding at different times.