共查询到20条相似文献，搜索用时 46 毫秒
1.
《Agricultural Water Management》1998,38(1):21-32
The effects of supplemental irrigation and irrigation practices on soil water storage and barley crop yield were studied for a crust-forming soil at the University of Jordan Research Station near Al-Muwaqqar village during the 1996/97 growing season. An amount of 0.0, 48.9, 73.3, 122.2 and 167 mm supplemental irrigation water were applied. The 48.9, 73.3 and 122.2 mm applications were applied through surface irrigation into furrows with blocked ends, and the 0.0 and 167 mm applications via sprinkler irrigation. The greatest water infiltration and subsequent soil storage was achieved with the 122.2 mm application followed by the 73.3 mm irrigation, both surface applied. Application efficiency (the fraction of applied water that infiltrated into the soil and stored in the 600 mm soil profile) and soil water storage associated with supplemental blocked furrow irrigation was significantly greater than with supplemental sprinkler irrigation. For arid zone soil, which has little or no structural stability, application of supplemental irrigation water via short, blocked-end furrows prevents runoff and increases the opportunity time for infiltration, thereby increasing the amount of applied water that is infiltrated into the soil and stored in the soil profile. Supplemental irrigation, applied by a low-rate sprinkler system, was not as effective because of the low infiltration rates that resulted from the development of a surface throttle due to dispersion of soil aggregates at the soil surface. The differences in stored water had a significant effect on grain and straw yields of barley. Without supplemental irrigation, barley grain and straw yields were zero in natural rainfall cultivation with a total rainfall of 136.5 mm. Barley yields in the control treatment, with a 167 mm supplemental sprinkler irrigation were low being 0.19 and 1.09 ton/ha of barley grain and straw, respectively. Supplemental irrigation through blocked-end furrows increased barley grain and straw yields significantly compared with supplemental sprinkler irrigation to a maximum of 0.59 and 1.8 ton/ha, respectively. The improvement coming from the increased water storage associated with furrows. Since irrigation water is very limited if available, farmers are encouraged to form such furrows for reducing runoff from rainfall thereby increasing the amount of water available for forage and field crop production. 相似文献
2.
Crop water use efficiency of irrigated cotton was hypothesized to be improved by a combination of minimum tillage and sowing a wheat (Triticum aestivum L.) rotation crop. This hypothesis was evaluated in a Vertisol near Narrabri, Australia from 1997 to 2003. The experimental treatments were: continuous cotton sown after conventional or minimum tillage and minimum-tilled cotton–wheat. Soil water content was measured with a neutron moisture meter, and runoff with trapezoidal flumes. Application efficiency of irrigation water was estimated as the amount of infiltrated water/total amount applied. Plant available water was estimated using the maximum and minimum soil water storage during the growing season. Evapotranspiration was estimated with the water balance method using measured and simulated soil water data. Seasonal evapotranspiration was partitioned into that coming from rainfall, irrigation and stored soil water. Crop water use efficiency was calculated as cotton lint yield per hectare/seasonal evapotranspiration. Rotation of cotton with wheat and minimum tillage improved water use efficiency in some years and application efficiency in all years. Average seasonal evapotranspiration was higher with minimum tillage than with conventional tillage. In years when cotton was sown in all plots, average cotton crop water use efficiencies were 0.23, 0.23 and 0.22 kg (lint)/m3 for minimum-tilled cotton–wheat and continuous cotton, and conventionally tilled continuous cotton, respectively. In-season rainfall efficiency, transpiration and soil evaporation were unaffected by cropping system. 相似文献
3.
总结了几种研究喷灌动能对土壤性能影响的方法 :单位面积动能对土壤入渗的影响 ;单位面积动能强度对土壤入渗的影响和不同的水滴撞击地面的角度对土壤入渗的影响。减小水滴打击地面动能的措施主要有 :在满足土壤结构不被破坏的前提下 ,尽量选择较小的喷头和喷嘴 ;减少喷灌强度和增加地表的覆盖度。同时与修整畦田、破除土壤表面的硬壳、以及喷施一定计量的化学物质 (如土壤改良剂 )等农艺措施相结合 ,可以更好的改善土壤结构 ,增加土壤的入渗水量 相似文献
4.
《Agricultural Water Management》1998,37(3):189-203
The effects of irrigation methods, application rates and initial moisture content on soil water storage and surface runoff were studied in soils liable to surface crust formation during 1995–1996 at the University of Jordan Research Station near Al-Muwaqqar village. Four irrigation methods were tested (sprinkler, furrow, basin and trickle) and four application rates (6.2, 14.4, 24.4 and 28.4 mm/h). Two runs were performed (soil initially dry and soil initially wet). Basin irrigation provided the highest application efficiency followed by trickle, sprinkler and furrow irrigation methods. Entrapping water by the basin borders increased soil water storage by allowing more water to infiltrate through the surface crust. Decreasing the application rate from 28.4 to 6.2 mm/h increased soil water storage significantly in all 150 mm layers to a depth of 600 mm. If the soil was already wet, soil moisture storage decreased owing to siltation during the prewetting and formation of a surface crust and low soil water storage capacity. A sedimentary crust formed at the bottom of the furrows in the furrow irrigation treatment, which reduced soil water storage and increased surface runoff significantly owing to the reduction in infiltration. Increasing the application rate from 6.2 to 28.4 mm/h in the furrow surface irrigation treatment increased the runoff discharge 10-fold. Even with the lowest application rate the runoff coefficient under sprinkler irrigation was 20.3% indicating high susceptibility of Al-Muwaqqar soils to surface crust formation. 相似文献
5.
6.
Farming practices, including tillage, cover cropping and residue management can have profound effects on the efficiency of irrigation practices. The effects of three field management practices (FMPs) standard tillage and winter-fallow (ST), standard tillage and winter-cover crop (STCC), and no-till and winter-fallow (NT) and two field lengths (122 and 366 m) on runoff and export of dissolved organic carbon (DOC) were investigated in a furrow-irrigated cropping system over two years. The residue cover was 40, 32 and 11% in 2007, and 58, 61 and 11% in 2008 for STCC, NT and ST, respectively. Furrow irrigation experiments were conducted prior to crop planting following the cover crop. The inflow was kept constant across all treatments, and infiltration and runoff were estimated using a volume balance model (VBM). The DOC concentration tended to increase with increasing field length, but did not differ among the FMPs. A threefold increase in field length increased infiltration by 40%, and decreased runoff by 60-90% and DOC export by 65-83%. In both years, infiltration was highest in STCC. In NT, infiltration was lowest in 2007, which was likely due to soil sealing, and intermediate among the three FMPs in 2008 perhaps due to the increase in residue cover in the second year. The DOC budget analysis showed that fields and FMPs acted as DOC sinks exporting less DOC than was applied in the irrigation water. The results suggest that longer furrows and STCC were greater DOC sinks compared to ST and shorter field practices. The VBM, as applied in this study to estimate infiltration and runoff, could be used to predict optimal field length to minimize runoff and promote DOC adsorption to soil within the constraints of water quality and availability and soil conditions. 相似文献
7.
Comparative studies of drainage and leaching under tillage systems in irrigated tropical and sub-tropical Vertisols are sparse. The objective of this study was to quantify drainage under cotton-based cropping systems sown on permanent beds in an irrigated Vertisol. Drainage and soil water storage were measured with the chloride mass balance method and neutron moisture meter, respectively, during the 2002-03, 2004-05, 2006-07 and 2008-09 cotton seasons in an on-going experiment in a Vertisol in NW NSW. The experimental treatments were: cotton monoculture sown either after conventional tillage or on permanent beds, and a cotton-wheat rotation on permanent beds where the wheat stubble was retained as in situ mulch into which the following cotton crop was sown. Subject to in-crop rainfall, irrigation frequency varied between 7 and 14 days for cotton and 2-3 months for wheat. In 2005, a split-plot design was superimposed on the existing experiment such that the main-plot treatments were irrigation frequency (“frequent”, 7-14-day irrigation interval; “infrequent”, 14-21-day irrigation interval), and sub-plot treatments were the historical tillage system/crop rotation combinations. In comparison with cotton monoculture sown either after conventional tillage or on permanent beds, soil water storage, particularly during the early part of growing season when rainfall provided the major proportion of crop water requirements, and drainage were greatest when a cotton-wheat rotation was sown on permanent beds. Seasonal drainage out of the 1.2 m depth, averaged among all seasons, was of the order of 25 mm, 33 mm and 70 mm with cotton monoculture sown either after conventional tillage or on permanent beds, and a cotton-wheat rotation on permanent beds, respectively. Soil water storage and drainage were also greater when irrigation frequency was greater. Seasonal drainage out of the 1.2 m depth, averaged between the 2006-07 and 2008-09 seasons, was 54 mm with “frequent irrigation”, and 28 mm with “infrequent” irrigation. Infiltration was less in management systems which resulted in wetter soil; viz. frequent irrigation or a cotton-wheat rotation on permanent beds with in situ stubble retention. Drainage water losses in a furrow-irrigated Vertisol may be reduced and soil water storage increased (i.e. water conservation improved) by sowing a cotton-wheat rotation with in situ stubble retention under less frequent irrigation. 相似文献
8.
Little information is available on the quantitative effects on crops of saline sprinkler irrigations and the presumable beneficial
effects of nocturnal versus diurnal irrigations. We measured crude protein content, carbon isotope discrimination and total
dry matter (TDM) of alfalfa (Medicago sativa L.) subject to diurnal and nocturnal saline sprinkler irrigations. The work was carried out in Zaragoza (Spain) during the
2004–2006 growing seasons with a triple line source sprinkler system using synthetic saline waters dominated by NaCl with
an irrigation water EC ranging from 0.5 to 5.6 dS m−1. The quality of alfalfa hay assessed through its crude protein concentration was not significantly affected by salinity.
Carbon isotope discrimination, an indicator of the effect of osmotic stress on plant water status, tended to decrease with
increases in salinity. Based on a piecewise linear response model, alfalfa grown under saline sprinkler irrigation was shown
to be more tolerant (threshold soil salinity, ECe = 3.5 dS m−1) than in previous experiments under surface irrigation (threshold ECe = 2.0 dS m−1) at relatively low salinity values, but became more sensitive at higher salinity values as shown by the higher absolute slope
(13.4%) for sprinkler as compared to surface irrigation (7.3%). No significant differences in TDM were found between diurnal
and nocturnal saline sprinkler irrigations. The recommended practice of irrigating at night for sprinkler irrigation using
saline water is therefore not supported by our results in alfalfa grown under semiarid conditions. 相似文献
9.
Field experiments were carried out over a 2-year period on a loamy soil plot under corn in Montpellier (south-east France). The effectiveness of improved irrigation practices in reducing the adverse impact of irrigation on the environment was assessed. Different irrigation and fertiliser treatments were applied to identify the best irrigation and fertilisation strategy for each technique (furrow and sprinkler) to ensure both good yields and lower NO3- leaching. No significant differences in corn yield and NO3- leaching were found for the climatic scenario of 1999 between sprinkler and furrow irrigation during the irrigation season. Following the rainy events occurring after plant maturity (and the irrigation season), differences in N leaching were observed between the treatments. The study shows that both the fertiliser method, consisting of applying a fertiliser just before ridging the furrows, and the two-dimensional (2D) infiltration process, greatly influence the N distribution in the soil. N distribution seems to have a beneficial impact on both yield and N leaching under heavy irrigation rates during the cropping season. But, under rainy events (particularly those occurring after harvesting), the N, stored in the upper part of the ridge and not previously taken up by plants, can be released into the deeper soil layers in a furrow-irrigated plot. In contrast, the 1D infiltration process occurring during sprinkler irrigation events affects the entire soil surface in the same way. As a result the same irrigation rate would probably increase N leaching under sprinkler irrigation to a greater extent than under furrow-irrigation during an irrigation period. In order to assess the robustness of these interpretations derived from soil N-profile analysis, a modelling approach was used to test the irrigation and fertilisation strategies under heavy irrigation rates such as those occurring at the downstream part of closed-end furrows. The RAIEOPT and STICS models were used to simulate water application depths, crop yield and NO3- leaching on three measurement sites located along the central furrow of each treatment. The use of a 2D water- and solute-transport model such as HYDRUS-2D enabled us to strengthen the conclusions derived from the observations made on the N distribution under a cross-section of furrow. This model helped to illustrate the risk of over-estimation of N leaching when using a simplified 1D solute-transport model such as STICS. 相似文献
10.
Seyed Majid Hasheminia 《Irrigation and Drainage Systems》1994,8(1):25-34
A research study was conducted in commercial potato production fields irrigated by low pressure center pivot irrigation systems for three growing seasons in southern Idaho, USA. Plots were established to give several replications of both conventional and reservoir tillage under the outermost spans, where the highest application rates occur. The soil was silt loam, and the topography varied from nearly level to 5% slopes. The sprinkler devices included spray nozzles on drops (spraydrops), spray nozzles on booms (spraybooms) and rotator spray nozzles on drops (rotator spraydrops) with an operating pressure of 138 kPa.The purpose of this study was to investigate and assess the role of reservoir tillage on controlling runoff, uniformity of soil water content throughout the field, and crop yield, as compared with conventional tillage. Reservoir tillage effectively reduced runoff losses to less than 1% of the applied water, when the dike were intact and remained stable. Over the three years of this study reservoir tillage increased the average soil water content by 18%. In addition, a statistical analysis showed that reservoir tillage significantly increased the percent available water in the top 65 cm of the root zone (P=0.01). The use of reservoir tillage elevated average yield by 21%, and average percent number one tubers was increased from 64% for conventional plots to 68% for reservoirtilled plots. While reservoir tillage increased the yield significantly (P=0.01), the sprinkler type did not have a significant influence on yield. 相似文献
11.
Assessing impacts of surge-flow irrigation on water saving and productivity of cotton 总被引：1，自引：0，他引：1
To improve water saving and conservation in irrigated agriculture, a range of field evaluation experiments was carried out with various furrow irrigation treatments in cotton fields to estimate the possibilities of improving furrow irrigation performances under conditions of Central Fergana Valley, Uzbekistan. The research consisted in comparing surge and continuous-flow in long furrows and adopting alternate-furrow irrigation. The best results were achieved with surge-flow irrigation applied to alternate furrows. Field data allowed the calibration of a surface irrigation model that was used to identify alternative management issues. Results identified the need to better adjust inflow rates to soil infiltration conditions, cut-off times to the soil water deficits and improving irrigation scheduling. The best irrigation water productivity (0.61 kg m−3) was achieved with surge-flow on alternate furrows, which reduced irrigation water use by 44% (390 mm) and led to high application efficiency, near 85%. Results demonstrated the possibility for applying deficit irrigation in this region. 相似文献
12.
An alternative water source and combined agronomic practices for cotton irrigation in coastal saline soils 总被引：1，自引：0，他引：1
Xiaobin Wang Quansheng Zhao Yujiao Hu Yan Zheng Xueping Wu Huijun Wu Guoxia Zhang Dianxiong Cai Clemencia Licona Manzur 《Irrigation Science》2012,30(3):221-232
The field experiment for cotton crop (Gossypium hirsutum L.) was conducted at the Zhongjie Farm, Huanghua city of Hebei province in the coastal salinity-affected areas in North China
Plain, to determine the effects of an alternative of irrigation water sources/methods and agronomic practices on seedling
emergence and yields of cotton, soil water–salt distributions, and soil pH changes during cotton growth stages. The experiment
was setup using split-plot design with two water sources as main treatments (well water/desalinized sea-ice water); two irrigation
methods (+PAM (Polyacrylamide)/−PAM); and four fertilization modes: check (CK), mineral fertilizer (F), mineral + organic
fertilizer (FM), and mineral fertilizer + gypsum (FG). Using desalinized sea-ice water irrigation showed the same effects
on top-soil salt leaching and desalinization as using well water did. There was no significant difference in seedling emergence
and cotton yields between two irrigation water sources for cotton irrigation. Using PAM-treated irrigation, the 10-cm top-soil
salinity significantly decreased to about 2.3–3.9 g kg−1 from 4.6 to 8.6 g kg−1 (PAM untreated). The PAM-treated irrigation increased seedling emergence by about 13, 29 and 36% and yields by about 50,
49, and 70%, with F, FM, and FG, respectively, as compared with CK. PAM-treated irrigation, either using well water or desalinized
sea ice, especially in combination with gypsum-fertilization, shows the best practice for both seedling emergence and cotton
yields. In conclusion, the desalinized sea-ice water used as an alternative water source, integrated with better agronomic
practices of soil water-salt management could be acceptable for cotton irrigation in the coastal saline areas. 相似文献
13.
轮胎压实对土壤水分入渗性能的影响 总被引：2，自引：0，他引：2
固定道保护性耕作可以有效地降低土壤压实程度,改善土壤结构。为此,以大田土壤水分入渗试验为依据,分析一年两熟区固定道保护性耕作系统对土壤水分入渗特性的影响,为其推广应用提供理论参考。试验结果显示:一年两熟区机具随机行走作业在表层土壤造成明显的压实;固定道保护性耕作可以降低0～30cm土层容重,降低0～40cm土层土壤紧实度,改善土壤结构,从而显著提高土壤水分入渗性能;相对于非固定道保护性耕作,固定道保护性耕作土壤水分稳定入渗强度提高111.1%,3h累积入渗量提高92.4%。 相似文献
14.
Summary A kinematic wave mathematical model which simulates the hydraulics of continuous flow furrow irrigation was linked with a crop yield model and used in combination with an economic model to analyze the effects of inflow rate, water infiltration characteristics and furrow length on uniformity of infiltrated water, runoff, gross profits and optimal number of 12 hour irrigations for corn (Zea mays) assuming other management practices to be constant. Higher uniformity of infiltrated water but more runoff and, in some cases, more deep percolation resulted from increased flow rates. Increases in uniformity of infiltrated water leads to greater profits, which are however offset by the associated increases in runoff and deep percolation. The study shows economically optimal water management for furrow irrigation can be obtained with proper balance between changes in the input variables and runoff and to some extent deep percolation.Contribution of the Department of Soil and Environmental Sciences, University of California, Riverside 92521. This study was supported by California State Water Resources Control Board Contract # 2-043-300-0 相似文献
15.
不同节水灌溉技术的节水机理试验研究 总被引：5，自引：1，他引：5
根据甘肃省特殊自然地理条件，对于喷灌、滴灌、渗灌及波涌灌几种方式下，小麦和玉米两种作物的灌溉节水机理进行了对比试验研究，分析了不同节水灌溉方式下这两种作物的节水性和生育动态。试验结果表明，在降雨、灌溉水量和前期土壤特性一定的情况下，在喷灌、滴灌、渗灌及波涌灌几种节水灌溉技术中，渗灌的节水性最好，依次为滴灌、喷灌、波涌灌。小麦和玉米在渗灌条件下产量比滴灌、喷灌和波涌灌都高，小麦渗灌产量比滴灌增加7．6％，比喷灌增加13．1％，比波涌灌增加22．4％。玉米渗灌产量比滴灌增加1．3％．比喷道增加6．3％。 相似文献
16.
Summary Irrigation with self-propelled moving sprinkler irrigation system (MSIS) enhances seal formation at the soil surface and results in large amounts of runoff and erosion which are aggravated by the MSIS high water application rate and reflected in lower yields. The effect of polyacrylamide (PAM) application (at the equivalent rate of 20 kg ha-1), prior to the irrigation season, on runoff and erosion from bare soil and soil covered with a crop, as well as on cotton yield was studied in a clay loam vertisol (Typic Chromoxert) and a silt loam loess (Calcic Haploxeralf). A center pivot and a lateral MSIS were used in the vertisol and loess, respectively. Vegetative growth of cotton plants in the vertisol was inversely related to water application intensity, which in turn affects runoff. PAM significantly reduced runoff in both the bare and crop-covered soils. The runoff level from the PAM treatments was 50–70% of that of the control. PAM also reduced erosion especially in the vertisol soil. However, the amount of eroded material carried by a unit runoff was similar in both treatments for both soils, indicating that PAM influences erosion by reducing runoff levels. A trend whereby PAM increased yield of cotton (Gossypium hirsutum L., cv. Pima S5) compared with the control was observed. Our results suggest that, under irrigation with a MSIS, reducing runoff is essential for obtaining higher yields. PAM is suggested as an effective tool to attain this target.Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No. 2866-E, 1989 series 相似文献
17.
18.
19.
20.
本文利用水文学中产流的基本原理,建立了喷灌强度及每次喷灌时间的计算模型。提出了允许喷灌强度可以大于目前多采用的稳定入渗速率的观点,从而可缩短喷灌所需时间,更好地发挥喷灌省水、省工的优点,为喷灌系统的设计提供依据。 相似文献