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[目的]制定砂质土壤马铃薯的喷灌灌溉制度。[方法]选择“夏波蒂”(抗旱性弱)和“费乌瑞它”(抗旱性强)2种不同抗旱能力的马铃薯品种,通过2a的田间试验,研究了不同土壤基质势阈值对土壤水分状况、马铃薯产量与灌溉水利用效率等的影响,以确定马铃薯适宜的土壤基质势阈值来指导灌溉。2012年布置了3个处理,在马铃薯定苗后分别控制垄中心20cm深度处土壤基质势阈值为-20、-30和-40kPa,2013年增加了1个-10kPa处理。[结果]大型喷灌机灌溉条件下监控垄中心20cm深度处土壤基质势可较好地调控马铃薯农田的土壤水分状况;①指导灌溉的土壤基质势阈值越高,马铃薯生育期内0~30cm深度平均土壤基质势越高,并且变化幅度越平缓;土壤基质势阈值越低,0~30cm深度平均土壤基质势越低,且变化越剧烈;40cm深度以下土壤水分状况与土壤基质势阈值的关系不明显。②不同抗旱能力马铃薯品种的产量都随着土壤基质势阈值的降低而线性降低,当阈值低于-15.8 kPa时,土壤基质势每降低1kPa,产量降低1.8%,且主要表现在大薯(W≥250g)和中薯(150g≤ W<250g)质量的降低,单株结薯个数基本不受影响。③灌溉水利用效率随着土壤基质势的降低而线性增加,表现为土壤基质势每降低1 kPa,灌溉水利用效率升高1.3%。[结论]砂质土壤大型喷灌机灌溉或类似农业生产条件下,推荐监控垄中心20cm深度处土壤基质势来指导施肥灌溉,并且土壤基质势阈值建议为-15.8 kPa左右,在淀粉积累期之后可考虑适当地降低土壤基质势阈值,以获得高产和较高的灌溉水利用效率。 相似文献
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日光温室滴灌条件下土壤基质势对番茄生长的影响 总被引：3，自引：0，他引：3
利用埋在滴头正下方0.2 m深度的真空表负压计,通过控制土壤基质势下限（-10 kPa,S1;-20 kPa,S2;-30 kPa,S3;-40 kPa,S4）,研究在太行山山前平原日光温室覆膜滴灌条件下土壤基质势对早春茬口普通番茄（Lycopersicon esculentum Mill.var. commune Bailey）生长的影响。试验结果表明：番茄的叶面积和叶绿素随土壤基质势的提高趋于增加;土壤基质势越高,产量越高;土壤基质势-30kPa时,灌溉水利用效率最高;番茄果实的Vc含量随土壤基质势的降级而降低;番茄果实的可溶性糖含量与土壤基质势的变化梯度没有关系。综合考虑番茄产量、品质和灌溉水利用效率,日光温室覆膜滴灌条件下,早春茬口番茄的土壤基质势控制在-20~-30 kPa最为适宜。 相似文献
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土壤水基质势研究进展 总被引：1，自引：0，他引：1
土壤水基质势是土壤水势的重要组成部分,在作物生长、径流、农田腾发和灌溉计划的制定等方面,是一个非常重要的参数。介绍了目前土壤水基质势的主要测定方法及其优缺点,总结了土壤水基质势在农业生产中的应用情况,并提出未来研究需要加强的几个方面。 相似文献
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《中国农村水利水电》2020,(8)
干旱区的平原水库造成坝后农田地下水位抬升,加剧了土壤盐渍化的程度,厘清干旱区平原水库对坝后农田土壤水盐运移规律,便于制定有效的措施来控制地下水位,进而抑制土壤盐渍化的发生。因此采用试验监测和数值建模,利用Hydrus软件模拟出坝后农田土壤水盐运移规律。结果表明:水库水位的变动影响下游农田地下水位的变化,水库水位越高,上下游水位差越大,渗流量就越大,地下水补给量增加,水位上升越快;土壤地下水位与含水率呈正相关,地下水位越高,含水率就越高;土壤的含水率与含盐量呈负相关。通过蒸发量的增大,水分被蒸发速度加快,含水率逐渐降低,将水中的盐分留在土壤中,地表聚盐速度增加,从而含盐量增加。土壤的深度越浅,变化越明显;因此地下水位的变化对水盐动态影响较大,是诱发盐渍化的内因。而气象因素的蒸发是水盐运移的原始驱动力,是诱发土壤盐渍化的外因。通过合理的措施有效的控制地下水位,可以降低或防止坝后土壤的次生盐渍化问题。 相似文献
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针对青海油菜农业生产对滴灌水肥管理及次生盐渍化防治的需求,布置了5个滴灌施肥灌溉比例(施肥量分别为当地油菜施肥量的10%、30%、50%,70%、90%)对油菜产量及水肥利用影响的田间试验,试验通过控制滴头正下方0.2m处的土壤基质势下限高于-20kPa进行滴灌水盐调控和施肥灌溉。试验结果表明:在青海高寒干旱地区、微咸水灌溉条件下,在滴灌高频灌溉阶段,0~0.4m油菜根系分布层土壤水分、盐分和养分状况良好,但当停止施肥灌溉后,土壤养分含量降低,表层土壤盐分升高,但0.3~1.2m土体盐分基本维持平衡。滴灌高频施肥灌溉有利于提高油菜的产量、肥料利用效率和灌溉水利用效率,并且当施肥比例为当地油菜施肥量的50%左右时,油菜产量高、肥料偏生产力较高。 相似文献
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张静萍 《国际沙棘研究与开发》2016,(4):59-62
本研究旨在实现水资源水质水量的优化配置,通过对水资源水质水量优化配置的生态经济学理论进行分析,指出水资源水质水量优化配置的概念,在内涵分析基础上确定了水资源水质水量优化配置的具体阈值原理和模型体系框架.同时对青海水资源水质水量的优化配置进行分析,指出不同区域的水资源水质水量需要进行针对性的优化配置. 相似文献
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刘海龙 《国际沙棘研究与开发》2017,(3)
在水资源管理中,水量水质联合调控主要是为了协调生态环境.利用运筹学、系统方法论、宏观经济学为计算基础,通过控制流域污染物来达到水质控制的目标.基于此,本文对水资源管理中水量水质联合调控的模式进行探讨. 相似文献
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《Agricultural Water Management》2004,65(1):1-19
The resource potential of shallow water tables for cropping systems has been investigated using the Australian sugar industry as a case study. Literature concerning shallow water table contributions to sugarcane crops has been summarised, and an assessment of required irrigation for water tables to depths of 2 m investigated using the SWIMv2.1 soil water balance model for three different soils. The study was undertaken because water availability is a major limitation for sugarcane and other crop production systems in Australia and knowledge on how best to incorporate upflow from water tables in irrigation scheduling is limited. Our results showed that for the three soils studied (representing a range of permeabilities as defined by near-saturated hydraulic conductivities), no irrigation would be required for static water tables within 1 m of the soil surface. Irrigation requirements when static water tables exceeded 1 m depth were dependent on the soil type and rooting characteristics (root depth and density). Our results also show that the near-saturated hydraulic conductivities are a better indicator of the ability of water tables below 1 m to supply sufficient upflow as opposed to soil textural classifications. We conclude that there is potential for reductions in irrigation and hence improvements in irrigation water use efficiency in areas where shallow water tables are a low salinity risk: either fresh, or the local hydrology results in net recharge. 相似文献
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郑云发 《国际沙棘研究与开发》2016,(7):34-37
农田水利建设一直是我国农业发展的重中之重,最初的农田一般仅依靠自然河水和雨水进行灌溉,而后由兴修的水利工程进行灌溉,农水建设发展到今天开始重视环境水生态.传统农田水利向环境水生态转变是一种必然的发展趋势.这种形式的转变能够最大限度地满足农业经济发展中的用水需求,而且不会对生态环境带来危害.本文主要分析农田水利发展对环境的影响,并概述了传统农业水利向环境水生态转变的过程. 相似文献
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尤小强 《国际沙棘研究与开发》2016,(6):74-77
在水利工程项目建设中,水闸工程项目占据着极其重要的作用.换言之,水闸工程质量的好坏,在很大程度上将直接关乎到整个水利工程项目的整体效果,包括使用寿命、功能发挥等.在工程建设过程中,水闸这一环节一旦出现了问题,对于整个工程及其下游地区,都会造成安全隐患,极大危害着当地居民的财产与生命安全.本文重点针对水利工程项目中的水闸设计环节,选取了春风河水利工程项目实例探讨,着重以该工程的水闸设计为研究对象,加以论述. 相似文献
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Non-conventional water resources and opportunities for water augmentation to achieve food security in water scarce countries 总被引：1，自引：0，他引：1
Given current demographic trends and future growth projections, as much as 60% of the global population may suffer water scarcity by the year 2025. The water-use efficiency techniques used with conventional resources have been improved. However, water-scarce countries will have to rely more on the use of non-conventional water resources to partly alleviate water scarcity. Non-conventional water resources are either generated as a product of specialized processes such as desalination or need suitable pre-use treatment and/or appropriate soil–water–crop management strategies when used for irrigation. In water-scarce environments, such water resources are accessed through the desalination of seawater and highly brackish groundwater, the harvesting of rainwater, and the use of marginal-quality water resources for irrigation. The marginal-quality waters used for irrigation consist of wastewater, agricultural drainage water, and groundwater containing different types of salts. In many developing countries, a major part of the wastewater generated by domestic, commercial, and industrial sectors is used for crop production in an untreated or partly treated form. The protection of public health and the environment are the main concerns associated with uncontrolled wastewater irrigation. The use of saline and/or sodic drainage water and groundwater for agriculture is expected to increase. This warrants modifications in the existing soil, irrigation, and crop management practices used, in order to cope with the increases in salinity and sodicity that will occur. 相似文献
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C. R. Jensen 《Irrigation Science》1982,3(2):111-121
Summary Barley plants (Hordeum distichum, L., cv. Zita) grown in a sandy soil in pots were adjusted during a pretreatment period of 5 days to three levels of soil water osmotic potential by percolating 61 of a nutrient solution with additional 0, 22.3 and 44.6 mM KCl. A drying cycle was then started and the plants were harvested when the soil water matric potential had decreased to –1.4 MPa, respectively 6, 7 and 8 days later.No significant differences in dry matter yields, transpiration coefficients and wilting percentages were found between treatments.During the drying cycle leaf water potential (
l
) decreased concomitantly with decrease in soil water potential (
s
) with almost constant and similar differences (
l
–
s
) for all treatments despite differences in levels of potentials. The concomitant decrease in leaf osmotic potential () was due partly to dehydration (58%) and partly to increase in leaf solute content (42%) independent of treatment. The part of total osmotic solutes due to K decreased relatively during the drying cycle.Close relationships were found between and
l
as functions of relative water content (RWC). Identical curves for the two levels of salt treatment agree with similar concentrations of K, Cl, and ash found for salt treated plants indicating that maximum uptake of macro nutrients may have been reached.During the main part of the drying cycle the turgor potential as function of RWC was higher and decreased less steeply with decreasing RWC in the salt treated than in the non-salt treated plants.In the beginning of the drying cycle additions of KCI lowered the transpiration rates of the salt treated plants resulting in a slower desiccation of the soil and hence an increased growth period. A delay in uptake from a limited soil water supply may be advantageous during intermittent periods of drought. 相似文献
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Production and water use in lettuces under variable water supply 总被引：3，自引：0，他引：3
M. Gallardo L. E. Jackson K. Schulbach R. L. Snyder R. B. Thompson L. J. Wyland 《Irrigation Science》1996,16(3):125-137
The effects of a variable water supply on the water use, growth and yield of two crisphead and one romaine (i.e., Cos) lettuce cultivar were examined in a field experiment using a line source sprinkler system that produced a range of water regimes that occur in growers fields. Four locations at increasing distances from the main line were monitored through the season (i.e., from thinning to harvest, 28–63 days after planting (DAP)). These locations at the end of the season corresponded to: (1) rewatering to field capacity (FC); (2) watering with a volume 13% below that required in the field capacity treatment (0.87*FC); (3) 30% below FC (0.70*FC); and (4) 55% below FC (0.45*FC). A linear production function for dry matter accumulation and fresh weight vs. crop evapotranspiration (ETc) was determined for lettuce during this period, giving a water use efficiency for dry matter of 1.86 g m–2 mm–1 and for fresh weight of 48 g m–2 mm–1 . For lettuce irrigated to field capacity, ETc between thinning and harvest was 146 mm; maximum crop coefficients of 0.81–1.02 were obtained at maturity (55–63 DAP). For the three irrigation treatments receiving the largest water application, ETc was higher in the Cos culivar than in the two crisphead lettuce cultivars which had similar ETc. Plant fresh weight was more sensitive than dry weight to reduction in water supply. In the FC treatment, root length density and soil water extraction were greatest in the top 0–45 cm, and decreased rapidly below 45 cm depth. Soil water extraction by roots increased at lower depths when irrigation was reduced. Instantaneous rates of leaf photosynthesis and leaf water potential showed no response to the irrigation treatments in this study, despite differences in biomass production. Evaporation was determined to be the major component of ETc for 45 of the 63 days of the growing season. The large loss of water by evaporation during mid-season and the apparent insensitivity of lettuce to the volume of irrigation during this period may provide an opportunity for reducing irrigation applications. 相似文献