论文标题:保水剂在节水灌溉中的应用及其对作物生长和水分利用的影响
The Effect of Exogenous cAMP on the Development of Mouse Hair Follicle and on the Cultured Dermal Papilla Cell
论文作者 杜太生
论文导师 康绍忠,论文学位 硕士,论文专业 农业水土工程
论文单位 西北农林科技大学,点击次数 116,论文页数 68页File Size3641k
2001-05-01论文网 http://www.lw23.com/lunwen_12042792/ 保水剂,节水农业,作物生长,水分利用效率
Super Absorbent Polymer,Water-saving Agriculture,Crop growth, Water Use Efficiency
发展节水农业，提高水的有效利用率，是保证干旱半干旱地区农业可持续发展的重要问题。保水剂的应用是一项重要的节水抗旱增产技术。本文以新型产品—“科瀚98”高效抗旱保水剂为材料，在对保水剂的吸水保水特性、保水剂与肥料的相互作用、保水剂对土壤物理性质的影响研究的基础上，采用温室盆栽试验与田间小区试验相结合的方法，研究了保水剂对作物生长及水分利用的影响，并在甘肃河西地区进行了应用研究。得出以下初步结论： （1）保水剂的吸水能力与所在溶液浓度呈负相关，在本地自来水中的溶涨度为195.9ml/g，保水剂保持的水分中80％是作物可以利用的有效水。当加入量为0.6％时，（土娄）土中83％的水分为有效水；保水剂具有明显的抑蒸保墒效应，恒温蒸发条件下保水剂处理沙土可延长蒸发时间，使土壤含水率明显增大；保水剂还能大幅度提高土壤含水率，使饱和含水量和田间持水量均有不同程度的增加。 （2）施用保水剂一定要考虑当地的灌溉条件和气候情况，针对不同的条件确定保水剂的施用方法、用量、相应的灌溉制度等问题。理想的保水剂施用方式是：既能使土壤中保持适度的水分胁迫（保水剂施用比例适当），以促进根系和地上部分的生长发育，从而为节水增产打下良好的基础；同时又不使土壤中的水分过少（灌溉方式适当），以免土壤含水率过低，形成保水剂与作物根系“争水喝”的现象。同时还应尽量选择耐旱作物品种，选择保水剂适宜的埋深和施用方式。 （3）相同保水剂用量时灌水量越大，土壤计划湿润层中保持的水分越多；在土壤垂直剖面上，似乎在20-40cm处形成了一个阻水层，沟施保水剂的处理该层含水率较高，但对深层土壤含水率影响不大。保水剂对株高影响不大，在灌水量较大时对玉米叶面积的增加有一定的促进作用；保水剂有刺激根系发育的作用；保水剂施用量的差异在玉米产量上反映明显。但灌水量较小时施用保水剂效果不显著甚至会造成减产；春小麦-玉米带田中沟施保水剂可明显提高灌溉水利用效率，在少量灌水时比灌水多时更明显。在产量相当时施保水剂15kg/hm~2可节约水量544.13m~3/hm~2。在灌水量相同时，沟施保水剂有一定的增产效果，在本试验范围内，施入保水剂越多增产效果越显著。 （4）保水剂不是造水剂，必须具备一定水分条件才能充分发挥其保水作用，从而达到节水增产的效果。施用保水剂的节水增产效果只有在一定的土壤水分条件下才能实现。保水剂的保水效果还受到保水剂的施用方式、土壤质地、水肥条件、气候、灌水模式等多种因素的制约。施用保水剂的经济合理性主要取决于三个因素：保水剂的价格及用量、增产效果及相应农产品的价格、节水效果及水价。
As far as the sustainable agriculture in arid and semiarid areas is concerned, it is an important problem to develop water-saving agriculture and increase Water Use Efficiency (WUE). Application of Super Absorbent Polymer (SAP) is an important technique to save water and fight a drought. In this paper, With a new SAP product named .EHAN 98? Super Absorbent Polymer as material and using glasshouse potted plant and field section experiment as main method, basing on researching the characteristic of SAP absorbing and holding water, interaction of SAP and fertilizer and effect of SAP on soil physics character, application of SAP in water-saving irrigation and its effect on crop growth and WUE are studied, field experiment has also been taken in Hexi area,Gansu province.The results are as follows: 1. SAP absorbent ability is negative correlation with the solution concentration. The retaining capacity of EHAN 98? SAP is 195.9ml/g in the tap water of our locality. 80 percent of water holding by SAP is available that can be easily used by crops. While adding 0.6 percent SAP of Lou soil (dry weight), 83 percent of water is available. SAP can decrease evaporation greatly, adding SAP to sand soil in the condition of evaporating at constant temperature, time of evaporation is extended, the moisture content of SAP treat is higher than CK. SAP can increase soil moisture greatly such as saturation moisture and field capacity. 2. While SAP is appreciated in the field, The method of using SAP its dosage and relevant irrigation system should be ascertained according to the different conditions such as irrigation and climate. The perfect method of using SAP should be as follows: Proper dosage of SAP is added to the soil and correct method of using it is adopted, forming moderate moisture intimidate in order to accelerate the growth of crops, thereby save water arid increase production; contemporary proper irrigation system should be adopted for fear that crops? root and SAP strive for water; in the same time, drought-enduring crops, the method of using SAP and its burying depth should also be considered. 3. Under the condition of the same dosage of SAP, water held in the soil increases with the quantity of water. At the vertical section of the soil, that is, 20 to 40 centimeters depth, it seems that a layer blocking water infiltration forms. SAP can increase moisture content of the layer but can抰 affect moisture content of deeper layer. SAP has less effect on maize height but more on leaf area, it can promote the growth of maize root. Maize yield is different when different dosage of SAP is added, but the effect of SAP increasing production on maize is little or minus when the water irrigated is less. In the spring wheat-maize cincture field in HeXi region, Gansu province, aplication of SAP in channel promotes irrigation WUE greatly. At the same yield of maize, SAP dosage of 15kg/bin2 can save water as much as 544. 13m3/hni2. At the same irrigation water use, SAP can increase maize yield. In range of the examination, the more the dosage of SAP is added, the more the yield of maize is produced. 4. The result of holding water, increasing production and saving water is affected by moisture condition, for SAP cannot produce water, it only can hold some water. A lot of conditions affect the resault of SAP such as method of using SAP, soil texture, water and fertilizer, climate and irrigation system. Economic rationality of using SAP lies on three factors: Price of SAP and its dosage, result of increasing production and price of the crops. quantit
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