在考虑作物投入时，我们经常想到化肥、杀虫剂、杀虫剂等，但我们经常忘记最简单和最重要的投入是水。了解植物如何利用水是很重要的，这样在需要的时候，比如在导致干旱的条件下，我们可以实施策略来限制植物在可能导致减产的胁迫条件下的时间。在研究干旱因素时，你经常会看到缩写ET。爱荷华州立大学的扩展和扩展状态“ET是土壤水分蒸发(E)和植物蒸腾(T)过程中使用的水的组合(爱荷华州立大学，2017)。爱荷华州立大学还将蒸腾作用定义为“水分从土壤通过植物进入大气的机制”(爱荷华州立大学，2017年)。“这是由于温度、太阳辐射和湿度使地球表面的水分蒸发的过程造成的。土壤蒸发是造成地表水分流失的关键因素，而降雨和高温又会加剧地表水分流失。结果表明，随着开花期的延长，蒸腾作用减弱，水分胁迫也随之增加(Blum, 1996)。土壤水分也是由四个相互作用的因素决定的:1。土壤中的水分2。土壤剖面特征3。作物的持水量4。对大气中水分的需求(普渡大学)。为了充分的作物生长和发育，土壤水分必须大于大气蒸发需求，否则在作物生命周期的任何时候都会导致产量下降。普渡大学(Purdue University)合作推广服务中心(Cooperative Extension Service)进行的一项研究得出的结论是，作物经历这些条件的时间通常是所有决定因素都增加的时候，比如6月至7月的仲夏月。此外，当植物处于水分胁迫下，它们更容易受到病害病原体、昆虫取食的影响，并表现出茎干完整性减弱。
When considering crop inputs we often think about fertilizers, pesticides, insecticides, and many more but we often forget the simple and most important input which is water. It is important to understand how the plant uses water so that in times of need such as in conditions that cause drought, we can implement strategies to limit the amount of time the plant is under the stress conditions that could cause yield reduction. When researching drought factors you will often see the abbreviation ET. Iowa State University Extension and Outreach states “ET is the combination of soil water evaporation (E) and water used by the plant during transpiration (T) (Iowa State University, 2017).” Iowa State also defines transpiration as “the mechanism by which water moves from the soil through the plant into the atmosphere (Iowa State University, 2017).” These are caused by the process in which temperature, solar radiation and humidity evaporate water from the earth’s surface. Soil evaporation is the key factor that is the cause of water surface loss, which is exacerbated following rain and high temperatures due to solar radiation and humidity. It was determined that when time to anthesis increases so does water stress when transpiration was reduced (Blum, 1996). Soil moisture is also determined by four interactive factors: 1. Amount of moisture in the soil 2. Characteristics of the soil profile 3. Moisture capacity of the crop 4. Demand for water in the atmosphere (Purdue University). For adequate crop growth and development, soil moisture must be more than atmospheric evaporative demand or it will result in yield reduction during any time of the crop life cycle. A study performed by Purdue University Cooperative Extension Service concluded that the time that crops experience these conditions are generally when all determining factors are increased like the mid-summer months of June-July. Furthermore, when plants are under water stress they’re more susceptible to disease pathogens, insect feeding influences and exhibit weakened stem integrity.
声明提醒 本文摘自网络请勿直接使用，为 Environmental 类作业。我们ESSAYEDUCATION作为澳洲老牌靠谱代写机构有能力为你提供很好的代写服务！如需代写请联系我们的客服