【作者】 刘佳；

【导师】 于海业； 张蕾；

【作者基本信息】 吉林大学 ， 农业生物环境与能源工程， 2014， 博士

【摘要】 滴灌系统一般由干管、支管、毛管这三级管网组成，管网主要以聚乙烯和聚氯乙烯塑料管材为主，它们与水接触的距离长、时间久、面积大，管材加工过程中的添加剂以及它们的分解产物向灌溉水中迁移，会改变水质成分、影响植物生长，在食物链的放大作用下，对人类健康存在潜在威胁。本文结合吉林省科技发展计划项目“温室小气候对灌溉水质受滴灌材料干扰效应的影响研究”(编号：20090169)，从滴灌生产实际出发，以聚氯乙烯和聚乙烯常用滴灌管材为研究对象，开展温室小气候条件对滴灌管材化学物质迁移的干扰效应研究。本文的主要研究内容和结论如下：1）为更好研究环境因素对UPVC滴灌管化学物质迁移影响，选择4种不同产地滴灌管为试验管材，研究在标准环境、实际温室环境以及温度变化对UPVC滴灌管向水中迁移重金属和有机化合物的影响进行分析，主要试验结果表明：①标准环境下，UPVC滴灌管12天TOC迁移总量已超过饮用水标准限制，但农田灌溉水标准中未规定TOC含量限定值；Pb元素最大迁移量是饮用水标准的289.9倍，是农田灌溉水标准的2.9倍，滴灌管向水中迁移Pb元素含量随时间的延长而递减；Fe和Al元素迁移量最大值均超过饮用水标准规定值，但农田灌溉水标准未对其加以限制；Ba和Zn元素迁移量均未超过饮用水标准和农田灌溉水标准限定值；②实际温室环境下，埋地40cm环境对UPVC滴灌管TOC和Ca元素迁移量的影响明显大于地表环境影响；埋地40cm环境和地表环境对Pb元素迁移规律没有影响，均随时间延长而减少，但就Pb元素迁移量而言，地表环境更有利于滴灌干管向水中迁移Pb元素；埋地环境对Al和Zn元素迁移量影响明显小于地表环境；两种环境对Fe和Ba元素迁移量影响不大；③温度影响：UPVC滴灌管TOC、Pb和Zn元素迁移量随温度升高而增大，高温环境对TOC和Pb元素迁移量增加影响明显；温度变化对Ca元素迁移量影响最大；④综合因素影响：UPVC滴灌管TOC和Al元素向水中迁移影响因素中，温度＞时间＞品牌；Ca元素：时间＞温度＞品牌；Pb元素：温度＞品牌＞时间；Fe元素：品牌＞时间＞温度；Zn元素：时间＞品牌＞温度。2）为更好研究环境因素对HDPE滴灌管有机物迁移影响，选择3种品牌HDPE滴灌支管和5种品牌HDPE滴灌毛管为试验管材，研究标准环境、环境因素变化以及实际温室环境对HDPE滴灌管向水中迁移有机化合物影响进行分析，主要结论如下：①标准环境下，HDPE滴灌管第一个72hTOC迁移量和TOC12天累积迁移量呈正向相关关系，且达到极显著水平；HDPE滴灌管随时间延长TOC迁移量呈先减后增趋势，并且滴灌毛管TOC迁移率在各个迁移周期内均明显小于滴灌支管。②温室环境下：HDPE滴灌管温室环境下TOC迁移量远远大于标准环境下，在27天迁移动态规律分析中随时间延长呈单峰趋势，并且在第9天管材向水中迁移TOC含量达到峰值。③环境因素影响：a.温度：从数值上看，HDPE滴灌管TOC迁移率随温度升高而增大；从增大幅度上看，并不是所有品牌HDPE滴灌管随温度升高其TOC迁移率大幅增长；b.空气相对湿度(RH)：RH变化对HDPE滴灌管TOC迁移率影响因品牌差异而各不相同，受RH影响最大品牌是5#管，最小的是8#管；c.光照：滴灌支管TOC迁移率受光照影响比滴灌毛管大。④综合因素影响：无论是HDPE滴灌支管还是HDPE滴灌毛管，除光照因素外因素主次顺序均为：时间＞温度＞品牌＞湿度；在含光照因素试验中，透光率因素因HDPE滴灌管功能不同而影响力不同。3）为更好研究灌溉水质对HDPE滴灌毛管有机化合物迁移影响，选择3种品牌HDPE滴灌毛管为试验管材，研究5种不同灌溉水质以及番茄营养液不同pH值对滴灌毛管有机化合物迁移影响、在HDPE滴灌毛管作用下，番茄营养液（pH=6）特征变化情况、以及在番茄营养液作用下，温度和光照环境因子对HDPE滴灌毛管有机化合物迁移影响，结论如下：①不同灌溉水质影响：标准环境下HDPE滴灌毛管向配制水和营养液中迁移TOC量远远高于向去离子水中迁移量，滴灌毛管向营养液中迁移TOC量表现为：番茄营养液＞黄瓜营养液＞非洲菊营养液；随着时间的延长，滴灌毛管向去离子水迁移TOC量越来越少，且减少趋势在一段时间内趋于平稳；向营养液中迁移有机物的趋势呈双峰曲线。滴灌毛管在不同灌溉水质作用下COD12天累积量为：配制水＞番茄营养液＞去离子水；②营养液不同pH值影响：对于番茄营养液而言，当pH=4时，对滴灌毛管TOC迁移影响最大，pH=5时，影响最小，这是因为在强酸性环境下，管材有机物迁移量更大；③HDPE滴灌毛管有机物迁移对营养液特性影响：营养液pH值随迁移周期延长而降低，但都高于初始pH值，HDPE滴灌毛管对EC值影响较小；④番茄营养液作用下温度和光照影响：a.温度：TOC迁移率最大值出现在40℃温度下，最小值出现在20℃温度下；COD值均随温度升高而增大；b.光照：迁移周期内HDPE滴灌毛管TOC累积迁移量均为：85%透光率＞50%透光率＞15%透光率，与标准环境相比，HDPE滴灌毛管向营养液中迁移有机物的含量都有大幅增长；⑤综合因素影响：在营养液作用下，影响HDPE滴灌毛管有机物迁移因素顺序为：时间＞温度＞品牌，时间＞透光率＞品牌，可见，迁移周期亦是非常重要的影响因素。4）为全面评价滴灌管材使用的安全性，对滴灌系统中干、支、毛三级管网在不同环境下72h浸泡液对种子萌发和根芽抑制效应及其发光细菌综合毒性进行研究，主要结论如下：①发光细菌急性毒性试验：a.UPVC滴灌干管标准环境下72h浸泡液相对发光度较高，低毒性灌溉水居多；温室环境下UPVC滴灌干管浸泡液毒性级别都在Ⅱ级以上；低温对UPVC滴灌干管浸泡液发光细菌急性毒性影响最大；b.HDPE滴灌管浸泡液相对发光度均随温度升高而降低，温度变化对HDPE滴灌支管浸泡液毒性等级影响不大，对HDPE滴灌毛管浸泡液毒性影响较大，尤其高温作用；c.环境因素对滴灌管材生物毒性影响顺序为：光照＞温度＞湿度；②滴灌管浸泡液种子发芽和根伸长的毒性试验：黑麦草和小麦分别是通过植物种子发芽和根伸长变化评价UPVC和HDPE滴灌管浸泡液更加理想的植物类型。更多还原

【Abstract】 Water pipeline in drip irrigation system is composed mainly of mainline, sub-main lineand capillary line. The materials of its network mainly use polyethylene and polyvinylchloride plastic tubing. As they contact with water for a long time, long distance and largearea, the pipe processing additives and their breakdown products migrate to irrigation waterand change the water quality ingredient, which effect the growth of plants. Then, under theamplified action of the food chain, the human health will be threatened potentially.According to the project of Science and Technology Development Program of Jilin―Theeffect of Greenhouse microclimate on Compounds migrating from Drip irrigation pipes‖(number:20090169), the dissertation proceeds from the drip irrigation production reality, bychoosing polyvinyl chloride and polyethylene as the research objects, carry out theinterference effects study of greenhouse microclimate on compounds migrating from dripirrigation pipes. The main research activities and results are as follows:1) In order to preferably study the environment effects on chemical substancesmigrating from UPVC drip irrigation pipe, four different brands of drip irrigation pipes arechosen as the test tube. In a standard environment, the greenhouse environment andtemperature variation influences on heavy metal migration and organic compounds areanalyzed. The main experimental results are shown as follow:①As12days experimental results in standard environment shows, the TOC migrationamount in mainline exceeds the limitation of drinking water quality standard; the biggest Pbcontent in tube is289.9times of drinking water quality standard and2.9times of farmlandirrigation water standard, the Pb migrating from mainline to water decreases with time; themaximums of Fe and Al migration exceed the limitation of drinking water quality standardas well(no irrigation water standard); the maximums of Ba and Zn are within the limitationof drinking water quality standard and irrigation water standard;②In the greenhouse environment, the TOC and Ca influences of undergroundmainline (-40cm) are obviously greater than ground-surface conditions. Different placementshave no effect on Pb migration, which decreases with time; the ground-surface environmentis benefit for Pb migration; Buried treatment has a less effects on Al and Zn migration thanground-surface environment; Two different placements have little effects on Fe and Bamigration;③Temperature influence: mainline TOC migration rate and Pb/Zn migration amount increases with rising temperature; higher temperature will clearly increase TOC and Pbmigration; the temperature variation has the biggest influence on Ca migration;④Analysis of comprehensive elements: for the influence factors to mainline TOC andAl element migration, temperature> time> brand; Ca: time> temperature> brand; Pb:temperature> brand> time; Fe: brand> time> temperature; Zn: time> temperature>brand.2) In order to preferably study the environment effects on organics migrations fromHDPE pipe, three different HDPE sub-main pipe brands and five different HDPE capillarypipe brands are chosen as the test objects. In standard environment, the greenhouseenvironment and environment variation influences on organic compounds migration areanalyzed. The main results are shown as follow:①In the standard environment, the first72h TOC release quantity from HDPE dripirrigation pipes is positively related to the12days TOC cumulative release quantity;Then,the TOC release amount initially decreases, but turns to increase with time;The mobility ofcapillary line TOC are less than sub-main pipe TOC mobility in various migration periods;②In the greenhouse environment: TOC migration from HDPE pipe is much greaterthan the standard environment; The dynamic analysis during27days shows a unimodaltrend, and the TOC migration in the9th day reaches the peak;③Environmental factors influences: a. Temperature: the TOC mobility from HDPEincreases with the temperature, and not all TOC migration increases with the temperaturesignificantly; b. Humidity: RH changes effects are different for TOC migration with differentbrands of HDPE pipes; RH has the greatest affects on No.5#tube, and the least effects onNo.8#tube; c. Lighting: the lighting effects on sub-main pipe TOC migrating is bigger thancapillary pipe;④Analysis of comprehensive factors: For HDPE sub-main pipe and HDPE capillarypipe, except the light factor: time> temperature> brand> humidity; including the lightfactor, the light transmittance influence are varied for HDPE pipe function.3) In order to study the effects of irrigation water quality impact on HDPE dripirrigation pipe better, three different HDPE capillary are chosen as the test objects, fivedifferent kinds of tested water and TOC migration effects of different tomato nutrientsolution pH values are studied. In the role of HDPE capillary pipe, tomato nutrient solution(pH=6) characteristics, as well as the temperature and light intensity influences on organicsmigration with their functions are discussed; the conclusions are as follows: ①Impacts of different tested water: in standard environment, the TOC migrationsfrom irrigation pipe to water and tomato nutrient irrigation are much higher than themigration quantity to distilled water; The TOC migration performance to the nutrientsolutions: tomato nutrient solution> cucumber nutrient solution> Gerbera nutrition liquid;With the extension of time, the capillary TOC migration to distilled water are less and less,and the reduction tends to stable over a period; the organics migrations to the nutrientsolution shows bimodal curves; For COD in12days, the accumulated amount of nutrientsolution under different irrigation water quality in capillary pipe: preparing water> thetomato nutrient solution> distilled water;②Different pH value effects of Nutrient solution: For tomato nutrient solution, whenpH=4, it has the biggest influence on capillary TOC migration, when pH=5, it has theminimal impact, this is because in the strong acidic conditions, the pipe organic have abigger migration quantity;③The organics migrating effects from HDPE capillary pipe on nutrient solutionfeatures: nutrient solution pH value decreased with the extension of the migration period.However, they are higher than the initial pH value; the tube stocks have less influence on ECvalue;④Temperature and light effects with the action of tomato nutrient solution: a.Temperature: the maximum migration rate of TOC was appeared on the temperature of40℃,the minimum value occurred at20℃; COD value increases with temperature; b. Lighting:Capillary TOC accumulation migration amount in migration period are as follows:85%lighttransmittance>50%light transmittance>15%light transmittance, compared with thestandard environment, the organics migration from pipe to nutrient solution has asignificantly increase;⑤The analysis of comprehensive elements: Under the effect of nutrient solution, theorder of the factors affecting the tubing organics migration: time> temperature> brand,time> light transmittance> brand, visible, the influence factors of migration cycle is alsovery important.4) For comprehensive evaluation of the drip irrigation pipe safety, the dissertation hasstudied the soaking liquids influences in mainline, sub-main line and capillary line within72h on seed germination, radical bud inhibition effect and luminescent bacteriacomprehensive toxicity, the main conclusions are as follows:①Luminescent bacteria acute toxicity test: a. In the standard environment,72h UPVCmainline soaking liquid has a high luminous intensity, low toxicity mostly in the irrigation water; the level of mainline soaking liquid in the greenhouse environment are over Ⅱmagnitude. Low temperature has the greatest impact on luminescent bacteria acute toxicityin mainline; b. the relative luminosity of HDPE pipe soaking liquid decreases withtemperature rise, and the temperature change have little influence on toxicity of dripirrigation pipe soaking liquid; the temperature has a large influence on capillary pipeimmersion toxicity, especially at the high temperature; c. Environment factors influences onthe tubing biological toxicity: light> temperature> humidity;②Seed germination and root elongation toxicity test of soaking liquids in dripirrigation pipe: through the plant seed germination and root elongation change evaluation,ryegrass and wheat, which is the ideal plant for UPVC and HDPE drip irrigation pipesoaking liquid is identified.更多还原