共查询到20条相似文献，搜索用时 15 毫秒
1.
Soil Erosion as A ffected by Polyacrylamide Application Under Simulated Furrow Irrigation with Saline Water 总被引：1，自引：0，他引：1
The reduction of soil and water losses under furrow irrigation with saline water is important to environmental protection and agricultural production.The objective of this study was to determine the effect of polyacrylamide(PAM)application on soil infiltration and erosion under simulated furrow irrigation with saline water.Polyacrylamide was applied by dissolving it in irrigation water at the rates of 1.5,7.5,and 15.0 mg L-1 or spreading it as a powder on soil surface at the rates of 0.3,1.5,3.0,and 6.0 g m-2,respectively.The effectrolyte concentration of tested irrigation water was 10 and 30 mmolc L-1 and its sodium adsorption ratio(SAR)was 0.5,10.0,and 20.0(mmolc L-1)0.5.Distilled water was used as a control for irrigation water quality.Results indicated that the effectrolyte concentration and SAR generally did not significantly affect soil and water losses after PAM application.Infiltration rate and total infiltration volume decreased with the increase of PAM application rate.Polyacrylamide application in both methods significantly reduced soil erosion,but PAM application rate did not significantly affect it.The solution PAM application was more effective in controlling soil erosion than the powdered PAM application,but the former exerted a greater adverse influence on soil infiltration than the latter.Under the same total amounts,the powdered PAM application resulted in a 38.2%-139.6% greater infiltration volume but a soil mass loss of 1.3-3.4 times greater than the solution PAM application. 相似文献
2.
Numerous studies have been conducted to examine the efficiency of PAM in controlling soil erosion under surface irrigation; however, there are fewer studies that have examined the effect of PAM on soil-water relations. This trickle irrigation laboratory study on a Jordanian clay loam soil addressed the effect of PAM on the spreading of the wetting front. PAM was added to the irrigation water under a trickle irrigation experiment where we irrigated the soil for 30 min. Four PAM concentrations (0.0, 5.0, 10.0, and 20.0 mg l?1) were used to examine its effect on the wetting front propagation in the soil. We also examined the effect of PAM on the soil water content, where we irrigated for 45 min, using two concentrations of PAM, 0.0 and 20.0 mg l?1. The soil water content was measured at depths of 0.0, 5.0, 10.0, 15.0, and 20.0 cm, 4 h, 24 h, and one week after completion of irrigation. PAM's effect on the soil water characteristic curve was studied using PAM concentrations of 0.0, 25, 50, and 100 mg l?1. In this study the spread of the wetting front on the soil surface and in the vertical and horizontal directions inside the soil profile increased when PAM was added to the irrigation water. As the PAM concentration increased the spreading of the wetting front increased. The average wetting front spreading increased in the vertical direction from 7.8 cm when PAM was not used to 8.3, 9.6, and 12.1 cm, for PAM concentrations of 5.0, 10.0, and 20.0 mg l?1, respectively. At the same time the average increase in the horizontal direction was from 18.4 to 18.5, 18.6, and 21.7 cm for PAM concentrations of 0.0, 5.0, 10.0, and 20.0 mg l?1, respectively. The second experiment showed that at a soil depth of 20 cm, volumetric soil water content (θv) was 15.2% when the irrigation water contained 20.0 mg l?1 of PAM compared to 13.9% when no PAM was added to the irrigation water. PAM did not have a significant effect on soil moisture characteristic curve. 相似文献
3.
Majed Abu-Zreig 《Journal of Soils and Sediments》2006,6(3):137-144
Background Several types of organic polymers with various molecular weights and surface charges are produced for various industrial
and agricultural purposes, and recent studies have shown that high molecular weight anionic polymers are the most effective
in reducing runoff and soil loss. However, anionic polyacrylamide (PAM) is marketed under various commercial names with variable
molecular weight and length according to its chemistry (Barvenik 1994). Consequently, its interactions with soil and efficiency
in reducing soil erosion are expected to vary. Moreover, types of PAM other than those recommended for erosion control may
also be effective in reducing soil erosion.
Objectives The objective of this research is to test the influence of 9 types of polyacrylamide (PAM) on water infiltration and soil
loss of an arid silt loam soil under simulated rainfall conditions.
Method logy. Nine types of organic polymers varied in surface charge, ranging from +20 to –75, and molecular weight ranging from
very low to very high were used in this study. Soil plots with dimensions of 60 cm by 120 cm having moderate slope of3 to
5% were constructed in the field and equipped with runoff collection installations. A specific type of PAM was spread on soil
plots at a rate of 10 kg/ha. Rainfall was supplied from a drip type rainfall simulator at constant intensity and duration
of 80 mm/h and 50 min, respectively. Runoff, infiltration and soil loss were measured for each plot subjected to a specific
type of PAM and compared to control plots.
Results and Conclusions Land application of PAMs significantly increased infiltration prior to runoff but had insignificant effect on total infiltration
volume and final infiltration rate under the present experimental conditions. Experimental results confirmed that anionic
polymers were more effective in reducing soil loss than that of non-ionic or cationic polymers. In fact the cationic, low
molecular weight and low surface charge non-ionic PAMs had insignificant effect on soil loss. High molecular weight anionic
PAM with 30% surface charge (A-130) was more effective(46% reduction) than those having a high molecular weight and a lower
surface charge of 20% (A-110 and A-120) with an aver-age soil loss reduction of 24%. The PAM A-836, described assoil erosion
polymer with 20% surface charge and high molecular weight, reduced soil erosion by 41%. Unexpectedly, the anionic PAM with
low molecular weight but very high surface charge was also effective in reducing soil loss (47% reduction).
Recommendations and Outlook Land application of PAM improves water infiltration and highly reduces soil erosion thus improving agricultural production.
Application of PAM could be the only viable way to improve arid land farming. It seemed that various types of PAMs, other
than those specifically produced for erosion protection can be used to combat soil erosion. This means that farmers in poor
countries can use any type of PAM that is available to them to improve agricultural production. 相似文献
4.
PAM与不同土壤调理剂混合施用对降雨入渗和土壤侵蚀的影响 总被引：3，自引：2，他引：1
土壤中施用聚丙烯酰胺(PAM)可以提高降雨入渗率,减少土壤侵蚀量。PAM大多施用于土壤表面。为了研究PAM与不同土壤调理剂混合施用对入渗率和侵蚀量的影响,对PAM(22.5kg/hm2)与保水剂(45kg/hm2)、粉煤灰(1 500kg/hm2)、腐殖酸(900kg/hm2)混合的6种施用方法进行了试验。结果表明,施加了PAM的土壤调理剂均能显著提高降雨入渗率和减少土壤侵蚀量。与对照相比,施加了PAM处理的降雨入渗率较对照试验提高了1.8～2.7倍,土壤侵蚀量减少约50%～70%,PAM与粉煤灰和腐殖酸混合施用提高降雨入渗率效果最为显著,PAM和保水剂混合施用减少土壤侵蚀量最多,PAM与粉煤灰和腐殖酸混合施用相比单独施用PAM均没有显著性差异。综合比较结果发现,PAM与粉煤灰混合施用增加降雨入渗率和减少径流的效果最好,PAM与保水剂混合施用抗土壤侵蚀效果最好。 相似文献
5.
微咸水入渗下施加PAM土壤水盐运移特性研究 总被引：11，自引：0，他引：11
土壤改良剂与微咸水灌溉相结合,对于合理开发利用微咸水、改善盐碱土结构及促进作物生长有着重要意义。基于一维垂直土柱积水入渗和水平土柱吸渗试验,研究了微咸水入渗条件下,不同聚丙烯酰胺(polyacrylamide,PAM)施量(0、0.02%、0.04%和0.06%)对盐碱土水盐运移特性的影响。结果表明:(1)微咸水入渗条件下,施加PAM能够降低土壤入渗速率,增加土壤保水性能。(2)施加PAM对Philip及Kostiakov入渗模型参数有显著影响,在PAM施量0.04%时,吸渗率S和经验系数K最小,而经验指数β最大。(3)在PAM施量为0.04%时,土壤饱和体积含水量最大,BrooksCorey模型进气吸力hd增加了15.30%,土壤持水性能显著提高;土壤水分扩散率最小,水分分布最均匀。(4)施加PAM能够显著提高土层的持水效率和微咸水的淋洗效果,在PAM施量为0.04%时,土层持水效率最高,盐分淋洗量最大。 相似文献
6.
聚丙烯酰胺增加土壤降雨入渗减少侵蚀的模拟试验研究Ⅱ.侵蚀 总被引：19，自引：0，他引：19
土壤侵蚀和雨水的流失是干旱、半干旱地区制约农业发展乃至生态环境良性循环的两个主要因素。聚丙烯酰胺 (PAM ,Polyacrylamide)对土壤的性质有着明显的改进作用 ,PAM具有良好的黏结力 ,能有效改良土壤的表层结构 ,提高土壤的稳定性 ,增加土壤的入渗率 ,减少土壤侵蚀。本文试图通过人工降雨模拟实验 ,获得不同的PAM的使用量及覆盖率与土壤侵蚀量在不同的雨强、不同的坡度条件下的关系。实验表明 ,经PAM处理后土壤的入渗性能和抗侵蚀的性能都有所提高 ,PAM能明显地黏结着土壤表面的颗粒 ,形成大的团聚体 ,阻碍土壤结皮的形成 ,减少土壤侵蚀。 相似文献
7.
PAM喷施量与施用方式对风沙土风蚀的影响 总被引：1，自引：0，他引：1
固定流沙和减少风蚀是一个世界性的难题。PAM(聚丙烯酰胺,polyacrylamide)作为一种线性高分子聚合物,喷洒在土壤表层能形成结皮,能有效抵御风蚀,但喷施PAM溶液的结皮状况及抗风蚀能力与PAM的喷施量及土壤特性等密切相关,且PAM溶液的浓度越大则黏性越强,越不易喷洒。为了探寻PAM防风固沙的适宜喷施量及简便施用方法,该研究以乌兰布和沙漠流动沙丘的风沙土为试验材料,以风沙土的风干土及饱和湿土为对照,首先探讨PAM不同喷施量对风干土(风沙土)表层结皮状况、土壤含水率及土壤风蚀量的影响,以寻求PAM的适宜喷施量,然后再将适量的PAM干撒、干撒后喷水和喷施于风干土表层,探寻PAM的简便施用方法。结果表明:1)PAM不同喷施量的结皮覆盖度、结皮厚度、结皮抗剪强度均随PAM喷施量的增加而增加,均显著高于风干土和饱和湿土;PAM不同喷施量的土壤含水率均高于风干土,且随时间的延续均显著高于饱和湿土;喷施1、2、3和4g/m2的PAM风蚀量分别为风干土的26.83%、14.10%、13.01%和13.00%,为饱和湿土的28.78%、15.12%、14.02%和13.94%,当PAM喷施量达到2 g/m2时,PAM能有效降低风沙土的风蚀量。2)将2g/m2的PAM干撒、干撒后喷水和喷施于风干土表层,干撒PAM后喷水和喷施PAM溶液的土壤结皮覆盖度、结皮厚度、结皮抗剪强度均高于风干土、饱和湿土和干撒PAM,干撒PAM的土壤表层结皮覆盖度低于饱和湿土但高于风干土,结皮厚度和结皮抗剪强度高于风干土及饱和湿土,干撒PAM后喷水及喷施PAM溶液的土壤含水率高于风干土、饱和湿土及干撒PAM,干撒PAM的土壤含水率与风干土基本一致。干撒PAM、干撒PAM后喷水和喷施PAM溶液的风蚀量分别为风干土的53.13%、11.17%和6.35%,为饱和湿土的76.34%、16.05%和9.12%,干撒PAM后喷水的抗风蚀能力接近于风沙土表层喷施PAM溶液。3)由于喷施PAM溶液需消耗大量的水分及人力,建议风沙区可在降雨前将2 g/m2的PAM干撒于土壤表层或干撒后向土壤喷水,可有效减少风蚀量。 相似文献
8.
9.
《Communications in Soil Science and Plant Analysis》2012,43(11-12):2171-2185
Abstract The adoption of polyacrylamide (PAM) in reducing irrigation‐induced erosion in California's San Joaquin Valley has been stymied by the lack of information about its toxicity and environmental fate. A review of the literature was conducted to bring to the forefront knowledge of polyacrylamide, its effectiveness in controlling erosion and its environmental fate. Polyacrylamide is a water‐soluble, high molecular weight synthetic organic polymer that primarily interacts with the clay fraction of soils. The degree of interaction depends on both the properties of the polymer and properties of the soil. It is effective in stabilizing soil aggregates, reducing soil erosion, and increasing water infiltration, and also has an indirect significant impact upon crop growth and yield. For the most part, polyacrylamide is resistant to microbial attack, and its degradation is mainly through physical breakdown. Polyacrylamide has been shown to be non‐toxic to humans, animals, fish, and plants; the only concern has been the toxicity of its residual monomer (acrylamide) content, which is a known neurotoxin to humans. The residual monomer is bio‐degradable and does not accumulate in soils. The major source of acrylamide that is released into the environment if from the use of polyacrylamide products, so the FDA regulates the residual monomer content of PAM used in food contact products. If the acrylamide content is kept to a minimum, PAM itself does not pose any environmental threat, and thus, can be used effectively as a soil conditioner. 相似文献
10.
聚丙烯酰胺施用量、初始含水率和容重对土壤水分入渗特性的影响 总被引：1，自引：0，他引：1
11.
聚丙烯酰胺对干旱半干旱区不同作物水分利用及产值的影响 总被引：3，自引：2，他引：3
为了在半干旱区和干旱区农业生产中推广应用聚丙烯酰胺(polyacrylamide,PAM),在半干旱区选择了西瓜、马铃薯、玉米和谷子,在干旱区选择了春小麦、向日葵、玉米和番茄,以不施PAM为对照,测定PAM对不同作物产量、产值、水分利用效率和水分生产率的影响。结果表明半干旱区西瓜、马铃薯、玉米和谷子的产量分别提高了36.76%、24.83%、20.20%和13.16%,产值提高了36.32%,23.04%,9.37%,10.18%,水分利用效率提高了30.15%,18.83%,13.42%和6.24%,水分生产率提高了30.57%,22.97%,16.79%和11.66%。干旱区春小麦、向日葵、玉米、番茄的产量分别提高了18.56%,12.82%,13.65%和16.54%,产值提高了12.78%,10.70%,9.53%和14.71%,水分利用效率提高了13.49%,17.03%,12.96%和25.12%,水分生产率提高了16.14%,11.62%,11.79%和14.85%。干旱区春小麦的增产率和增值率虽然高于向日葵,但增产值却极显著低于向日葵。建议半干旱区应用PAM应优先选择西瓜和马铃薯,干旱区应优先选择番茄和向日葵。 相似文献
12.
聚丙烯酰胺对地表氮素流失的影响研究 总被引：2，自引：1，他引：1
地表侵蚀条件下氮素的流失致使表层土壤退化及养分供给能力降低。在室内模拟降雨条件下,重点研究了高分子有机化合物聚丙烯酰胺(PAM)施用对泥沙氮素吸附能力及氮素流失水平的影响。试验施氮用肥为尿素,施氮水平设定为270kg/hm2,试验设定3个PAM施用水平(0,1和2g/m2),并设置不施氮也不施PAM作为对照处理,每个处理3次重复。试验分别在2个降雨强度(50和80mm/h)下进行。结果表明,PAM可以很好地维持土壤结构的稳定性,抑制地表细沟侵蚀的产生,从而有效地降低侵蚀产沙的水平。PAM的施用增强了泥沙对氮素的吸附水平,所以施用PAM的处理地表氮素流失仍明显减少,且氮素流失过程表现出与产沙过程很好的一致性,这说明PAM减少氮素流失的原因在于控制侵蚀产沙的水平。PAM的施用可以有效抑制地表泥沙和氮素的流失。 相似文献
13.
聚丙烯酰胺的水土保持机制及研究进展 总被引：8，自引：0，他引：8
水土流失是我国主要环境问题之一。聚丙烯酰胺(PAM)作为一种高分子聚合物,具有絮凝作用和水合作用,可提高土壤水分入渗,减少地表径流。PAM对土壤无毒害作用,可保肥、增产、集雨,在农业生产中具有广泛的应用前景。针对PAM的水土保持功能,介绍PAM水土保持机制、施用过程中涉及的关键因素、应用前景及存在的问题。PAM的类型较多,水土保持效果随施用类型、施用方法、施用量变化而不同。PAM在水土流失治理过程中应与当地的土壤、气候、地貌、植被等密切结合,才能发挥其最大功能。今后研究中应注重PAM施用后土壤侵蚀通用模型的建立及新型PAM产品的开发,为PAM在水土保持中的推广提供理论依据。 相似文献
14.
秸秆生物炭对黏壤土入渗规律的影响 总被引：3，自引：0，他引：3
为提高干旱半干旱区耕作土壤灌溉水的利用效率,采用秸秆生物碳对黏壤土进行改良,并用3种经典入渗模型进行入渗模拟,寻求适于描述研究区土壤入渗规律的模型及改良方案。采用双环入渗试验测定4种生物炭施用水平（10 t/hm2,20 t/hm2,30 t/hm2,50 t/hm2）的田间作物生育期内土壤含水率、入渗速率及累积入渗量,分别采用Green-Ampt模型、Philip模型和Kostiakov经验公式对试验组与对照组（CK）的入渗过程进行模拟。结果表明:施用量为30 t/hm2较CK效果最为明显,施用层（0—40 cm）入渗速率增加44.6%,耕作层土壤含水率增加8.9%,累积入渗量增加45.45%。比较3种模型的入渗过程拟合结果,认为Kostiakov经验公式拟合的效果符合实测规律,可为研究区改良土壤水分入渗过程提供理论依据。 相似文献
15.
土壤水蚀中关于化学因素的研究现状和展望 总被引：4，自引：4，他引：4
土壤水蚀是一个复杂的物理化学过程。化学因素在土壤水蚀过程中起了相当重要的作用。该文系统分析了土壤溶液浓度和组成对土壤团聚体稳定性、地表硬壳形成以及土壤水力传导度、入渗率、地表径流和土壤侵蚀的影响；探讨了长期劣质水灌溉可能对土壤侵蚀产生的影响以及减少劣质水灌溉区土壤侵蚀的化学方法；指出土壤表面密封层对土壤侵蚀的影响及其机理描述是土壤侵蚀研究中的一个重要研究方向。 相似文献
16.
土壤调理剂PAM的农用研究和应用 总被引：32，自引：0，他引：32
90年代 ,新型PAM产品 (具有很高分子量的阴离子型PAM )和改进的应用技术 (低用量配合灌溉水 )使得PAM在农业上的使用成本大大减少 ,而农用效益大大提高 ,土壤调理剂PAM的农用重新受到重视。目前美国西部已将PAM的农用作为一项农田水土保持新技术而得到越来越广泛的应用。土壤调理剂PAM曾于 80年代后期介绍到我国 ,但是由于成本高等其它问题而未能在农业上推开 ,目前新型PAM的农用研究也在我国引起重视。国外大量研究和国内有关研究表明 ,PAM的农用效益体现在水土保持、灌溉效率、农业生产、环境、经济等方面。土壤调理剂PAM用于农田水土保持、防止水土流失前景看好 相似文献
17.
中性多聚糖(Jag S)是一种新型高聚物,研究该高聚物对黄土坡面降雨入渗的影响可对采用土壤侵蚀化学调控技术措施防治黄土坡面土壤侵蚀提供新的理论基础。通过人工模拟降雨试验,研究不同雨强(1.0、1.5、2.0 mm min-1),不同坡度(10°、15°、20°)条件下,坡面降雨入渗及产流时间与喷施不同剂量(1、3、5 g m-2)Jag S之间的关系。结果表明:在不同坡度不同雨强下,与裸露坡面相比,喷施3种剂量的高分子化学材料Jag S均减少了前期降雨入渗率,但1及3 g m-2剂量Jag S处理能够明显提高黄土坡面入渗性能,减缓入渗在整个降雨过程的下降趋势,提高稳渗率,强化入渗效应均值分别为21.53%及9.17%,大剂量(5 g m-2)Jag S反而降低了土壤入渗性能(小雨强下除外)。喷施不同剂量Jag S的坡面其产流开始时间差异很小,但均早于裸露坡面,且表现为Jag S喷施剂量越大,坡面越早产流,大坡度大剂量对降雨产流时间影响较大。三个剂量对应产流时间提前百分比均值分别为47.26%、50.47%及66.28%。总之,Jag S在一定程度上能改善黄土坡面土壤结构,提高黄土坡面降雨入渗性能,从而降低土壤侵蚀,为采用高聚物进行水土保持提供了科学依据。 相似文献
18.
盐渍土壤通常因盐分含量大、pH偏高、结构差、水盐运动强烈等原因，植物难以生长。本研究选择聚丙烯酰胺（Polyacrylamide，PAM）、壳聚糖（Chitosan，CTS）、羟乙基纤维素（Hydroxyethyl Cellulo，HEC）等3种高分子化合物，以土壤表面喷洒高分子化合物溶液成膜的方式，研究了高分子化合物膜对盐渍土壤基本物理性质与水分蒸发的影响，结果表明：本研究选择的3种高分子化合物能够不同程度的降低土壤水分蒸发、提高土壤保水性能和显著抑制土壤盐分的表聚，利用主成分分析进行对比发现：PAM 20 kg/hm2、CTS 80 kg/hm2、HEC 80 kg/hm2的用量下的土壤抑蒸控盐效果最佳，盐渍土表喷洒高分子化合物溶液成膜对盐渍土壤改良利用具有确切的正效应。 相似文献
19.
Soil amidase activity in polyacrylamide-treated soils and potential activity toward common amide-containing pesticides 总被引：1，自引：0，他引：1
Jeanine L. Kay-Shoemake M. E. Watwood Robert E. Sojka Roderick D. Lentz 《Biology and Fertility of Soils》2000,31(2):183-186
Polyacrylamide (PAM) is currently used as an irrigation water additive to significantly reduce the amount of soil erosion
that occurs during furrow irrigation of crops. Elevated soil amidase activity specific toward the large PAM polymer has been
reported in PAM-treated field soils; the substrate specificity of the induced amidase is uncertain. PAM-treated and untreated
soils were assayed for their capacity to hydrolyze the amide bond in carbaryl (Sevin), diphenamid (Dymid), and naphthalene
acetamide. Based on results obtained with a soil amidase assay, there was no difference between PAM-treated and untreated
soils with respect to the rate of amide bond hydrolysis of any of the agrochemicals tested. It appears that under these assay
conditions the PAM-induced soil amidase is not active toward the amide bonds within these molecules. However, carbaryl was
hydrolyzed by a different soil amidase. To our knowledge, this is the first soil enzyme assay-based demonstration of the hydrolysis
of carbaryl by a soil amidase.
Received: 23 June 1999 相似文献
20.
PAM改善黄土水土环境及对玉米生长影响的田间试验研究 总被引：10，自引：8，他引：10
在干旱半干旱地区，为了充分利用有限的降水资源，促进农作物的生长，采用聚丙烯酰胺(PAM)进行了减少玉米田土壤表面的径流，增加土壤入渗的试验。试验区位于内蒙古自治区清水河县境内，在试验区挑选一块坡面相对比较平整坡度在5%～7%的连片玉米田，分别在玉米田的土壤表面采用4个不同的处理，即PAM覆盖率80%、60%、40%和对照，试验采用3个重复。通过小区试验，测定降雨在土壤表面形成径流量、土壤的含水量的变化情况和玉米生长发育的状况，以及玉米的全干物质产量。结果表明，PAM能够很好地增加土壤的有效降雨量并促进玉米的生长。 相似文献