微咸水膜下滴灌对西葫芦生长影响及水盐生产函数研究

发布时间：2018-03-02 10:08

本文关键词： 微咸水膜下滴灌土壤水盐分布西葫芦水盐生产函数　出处：《太原理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：水是生命之源,万物之本,是人类生存与发展不可或缺的重要资源之一。目前,随着我国社会和经济的发展,淡水资源短缺的问题日益突出,已成为制约我国经济和社会可持续发展的瓶颈。膜下滴灌与微咸水灌溉相结合的灌溉新方法能有效缓解我国淡水资源的供需矛盾。进行不同矿化度与灌水上下限处理,探究适宜的水盐水平是保证西葫芦高产的重要的基础。为此,本文采用田间试验与理论分析相结合的研究方法,对膜下滴灌条件下不同灌溉水矿化度和水盐耦合对土壤水盐分布及西葫芦生长的影响进行了研究。不同灌溉水矿化度对西葫芦生长影响研究的控制因子为灌溉水矿化度,设置了三个水平,分别为1.7、3.5和5.1g/L,在西葫芦整个生育期,灌水量通过灌水上下限控制,灌水上限为田间持水率的90%,灌水下限为田间持水率的70%。具体研究成果如下:(1)不同矿化度处理的灌前土壤含水率垂向分布规律一致,均随土层深度的增大而增大,灌后的土壤含水率大致呈现椭圆形分布,滴头正下方土壤含水率最高,距离滴头越远,含水率越低。不同矿化度处理后的湿润体范围和含水率大小不同,当矿化度越高时,湿润体越窄深,土壤含水率越高。三种矿化度处理下的土体平均含水率随时间呈现波浪状的变化趋势,在20~50cm深度范围,三者的数值大小表现为:5.1 g/L3.5 g/L1.7 g/L。(2)不同矿化度处理的灌前土壤盐分垂向分布规律一致,均随土壤深度的增加而减小,三种处理下盐分大小及分布特征基本接近。灌后的土壤盐分呈现椭球型分布,距离滴头位置越远,土壤盐分越大。三种处理的灌后盐分数值大小表现为:5.1g/l3.5g/l1.7g/l。通过膜下滴灌能够使土壤表层盐分淋洗,进入深层土壤,并远离根系集中区。在全生育期结束后,在滴头下方,三种矿化度处理下的土壤盐分随深度呈现逐渐减小的变化趋势。1.7g/l处理积盐区主要集中在20~30cm土层,3.5g/l和5.1g/l处理的积盐区主要集中在20~40cm土层。(3)不同灌水矿化度处理后的西葫芦出苗率、株高、叶面积指数、根部鲜重、冠部鲜重、根冠比具有相同的动态变化趋势。不同矿化度处理下的出苗率和株高均随时间呈现先快速增大,然后逐渐趋于稳定的变化趋势,而叶面积指数呈现先逐渐增大然后逐渐减小的变化趋势。不同矿化度处理下的根部鲜重和冠不鲜重随时间呈现逐渐增大的变化趋势,而根冠比呈现逐渐减小的变化趋势。不同矿化度处理下的出苗率和叶面积指数大小表现为:1.7g/l3.5g/l5.1g/l。经1.7g/l和3.5g/l处理后的株高大小基本接近,并明显大于5.1g/l处理。不同矿化度处理下的根冠比大小表现为:5.1g/l3.5g/l1.7g/l。膜下滴灌水盐耦合对西葫芦生长影响研究设置了4个因素,其中3个因素是西葫芦的生育阶段,分别为:幼苗期、抽蔓期、开花结果期,西葫芦的3个生育期分别设置了3个水分水平,灌水上下限分别70%~90%、60%~80%、50%~70%,另外1个因素是水质因素,设置了3个灌水矿化度水平,分别为1.7、3.5和5.1g/l,采用正交试验设计,共9个处理(t1~t9)。具体研究成果如下:(1)不同水盐耦合处理下的土壤平均含水率随时间具有相同的变化趋势,均具有锯齿状的波动变化特征。不同水盐耦合条件下的土壤盐分均值随时间具有相同的变化趋势,在1.7g/l和3.5g/l处理下,呈现逐渐减小的变化趋势,但在5.1g/l下,呈现逐渐增大的变化趋势。灌水上下限和灌水矿化度越高时,土壤平均含水率越高。灌溉水矿化度越大,土壤平均盐分越大。灌水上下限对土壤盐分大小无显著影响。(2)不同水盐耦合条件下的株高和叶面积指数随时间具有相同的变化趋势,株高呈现逐渐增大然后趋于稳定的变化趋势,叶面积指数呈现先逐渐增大然后逐渐减小的变化趋势。土壤中控制的含水率越大,矿化度越小时,西葫芦株高和叶面积指数越大。(3)不同水盐耦合条件下的作物耗水量随时间呈现逐渐增大的变化趋势,即幼苗期抽蔓期开花结果期。随着灌溉水矿化度的提高,西葫芦的耗水量逐渐减小。西葫芦产量从大到小依次为:t2处理t1处理t5处理t6处理t9处理t7处理t8处理t4处理t3处理。西葫芦产量随灌溉水矿化度增大呈现逐渐减小的变化趋势。最优水盐耦合灌溉方案为:矿化度为1.7g/l,幼苗期70%~90%、抽蔓期60%~80%、开花结果期60%~80%。膜下微咸水滴灌条件下西葫芦总产量和总耗水量两者间符合二次抛物线关系,以此估算出最佳耗水量为296mm。(4)在试验的基础上用修正后的jensen模型建立了西葫芦的水盐生产函数模型,得出水分敏感指数λ大小表现为:开花结果期抽蔓期幼苗期,盐分敏感指数σ大小表现为:幼苗期抽蔓期开花结果期,并采用实测数据对模型进行验证,结果表明模型具有较高的模拟精度,可用于西葫芦产量的预测。
[Abstract]:Water is the Source of Life, all of this, is one of the important resources for human survival and development. At present, as China's social and economic development, shortage of water resources has become increasingly prominent, has become a bottleneck restricting the sustainable development of China's economy and society. The contradiction between supply and demand of the new method of irrigation under film drip irrigation combination with brackish water irrigation can effectively alleviate water resources in our country. The different salinity and irrigation limits, explore the suitable level of salt water is to ensure high yield of Zucchini important basis. Therefore, the field experiment and theory analysis, the drip irrigation under different irrigation the water salinity and water salt coupling are carried out to study the effects on soil water salt distribution and growth of pumpkin. Different irrigation water salinity on the growth of pumpkin as the controlling factors on the effect of irrigation water salinity. The three level, respectively 1.7,3.5 and 5.1g/L in pumpkin during the whole growth period, the amount of irrigation by controlling the lower limit of irrigation, irrigation maximum field capacity 90%, irrigation threshold was 70%. water rate the results of specific studies are as follows: (1) the different degree of mineralization of soil water content before irrigation treatment the vertical distribution of favorable, increased with soil depth increasing, soil water irrigation rate of roughly elliptical distribution, drippers of soil moisture is highest, farther away from the emitter, the lower water content. Different degree of mineralization after wetting range and water content of different sizes, when mine the degree is higher, the more narrow wetting depth, soil moisture content is higher. Three kinds of soil salinity under the average moisture content of the time with a wavy trend, in the depth of 20~50cm, three numerical size is: 5.1 g/L3.5 g/L1.7 g/L. (2) of different ore The degree of treatment before irrigation soil salinity vertical distribution were consistent, decreased with the increase of soil depth, the three treatment the size and distribution of Salinity Characteristics basically. Soil salinity after irrigation showed elliptical distribution, farther away from the emitter, soil salinity is greater. Three kinds of treatment after irrigation of salt the numerical size is as follows: 5.1g/l3.5g/l1.7g/l. by drip irrigation can make the soil surface salt leaching, deep into the soil, and away from the root zone. During the whole growth period after the end, under the dripper, three salinity treatment under soil salinity with depth showed a gradual decrease trend of.1.7g/l processing mainly concentrated in the salt accumulation zone. The depth of 20~30cm, 3.5g/l and 5.1g/l of the salt accumulation zone mainly concentrated in the 20~40cm soil layer. (3) different water salinity treated squash germination rate, plant height, leaf area index, root fresh weight, fresh weight of shoot, root shoot ratio Has the same change trend. Different degree of mineralization under the treatment of germination rate and plant height with time showed the first increase quickly, and then gradually tends to be stable, and the leaf area index showed a trend of first increase and then decrease gradually. The different degree of mineralization under the fresh weight of root fresh weight over time is not Wacom show the increasing trend, and the trend of root shoot ratio showed a gradual decrease. Under different salinities germination rate and leaf area index size is: 1.7g/l3.5g/l5.1g/l. the size height 1.7g/l and 3.5g/l after treatment were close, and was significantly higher than that of 5.1g/l. Different degree of mineralization under the root shoot ratio for size 5.1g/l3.5g/l1.7g/l.: drip irrigation water salt coupling on the growth of pumpkin effect on the set of 4 factors, the 3 factor is the growth stage of summer squash were: Seedling , vining stage, flowering stage, 3 stages of summer squash were set up 3 water level, irrigation limits were 70%~90%, 60%~80%, 50%~70%, the other 1 factors are water quality factors, set up 3 water salinity levels were 1.7,3.5 and 5.1g/l, using orthogonal design, a total of 9 treatment (t1~t9). The results are as follows: (1) the soil water and salt under different coupling average moisture content has the same trend with time, fluctuation characteristics are jagged. Different coupling between water and salt under the condition of mean soil salinity with time have the same trend, in 1.7g/l and 3.5g/l next, decreases gradually, but in the 5.1g/l, show the increasing trend. On the lower limit and the irrigation water salinity is higher, the average soil water content is higher. The average salinity of irrigation water, soil salinity irrigation is greater. On the lower limit of soil salinity had no significant effect on size. (2) the different coupling between water and salt under the condition of plant height and leaf area index has the same trend with time, plant height increases and then tends to be stable, the leaf area index showed the first increases and then decreases. The change trend of soil moisture control the rate is bigger and the degree of mineralization is smaller, the squash plant height and leaf area index is larger. (3) the different coupling between water and salt under the condition of crop water consumption gradually increased with time, the seedling vine flowering stage. With the increasing salinity of irrigation water, the water consumption of summer squash decreased gradually. The yield of pumpkin from large to small is as follows: T2 T1 T5 T6 T9 with T7 T8 T4 T3 treatment. The yield of pumpkin with irrigation water salinity increased gradually decrease trend. The optimal Water and salt coupling irrigation scheme: salinity is 1.7g/l, seedling 70%~90%, vine 60%~80%, the flowering stage of 60%~80%. film under drip irrigation with saline water under the condition of squash total yield and total water consumption between the two with two parabolic relationship, in order to estimate the optimal water consumption is 296mm. (4) established the water salt production the function model of summer squash with the modified Jensen model on the basis of the experiment, the water sensitive index is as follows: fruiting size of vine seedlings, a salt sensitive index size performance: Seedling vine flowering stage, and the use of the model was validated with measured data, the results show that the simulation accuracy of the model is high, can be used to predict the yield of pumpkin.

【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S275.6;S642.6

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