【作者】 侯国华；

【导师】 韩烈保； Yaling Qian；

【作者基本信息】 北京林业大学 ， 草业科学， 2011， 博士

【摘要】 城市绿地的建植和养护需要消耗大量水资源,随着城市化建设进程日益加快,供水紧张问题日显突出,再生水和杂排水灌溉是缓解水资源危机的重要举措,开展再生水和杂排水灌溉对绿地植物及土壤性质的影响研究对于实施再生水和杂排水灌溉具有重要的理论意义和应用价值。本论文通过定点取样分析,从时间和土壤深度两个角度,研究了再生水灌溉五年对城市绿地土壤理化性质的影响；以自来水灌溉为对照,比较研究了杂排水长期灌溉对植物生长状况的影响,分析了杂排水长期灌溉对植物组织矿质含量的影响,并对景观植物耐盐性与杂排水灌溉忍耐性之间的相关性进行了研究；针对再生水和杂排水长期灌溉钠害的问题,开展了再生水沸石除钠技术研究。主要研究结果如下：1、选取科罗拉多州7个草坪27个采样点,比较再生水5年灌溉对土壤理化性质的影响,考察参数包括土壤pH值、Na含量、EC值、SAR值、Ca和Mg含量、NO3-N、P、K、OM、Zn、Fe、Mn、Cu、Cl和B。结果表明：从时间角度上看,再生水灌溉五年土壤Na含量、K含量、pH值、SAR和Ec值均有显著提高,Mn含量有显著下降,而土壤OM、Ca、Mg、NO3-N、P、Zn、Fe、Mn、Cu、Cl和B含量未出现显著变化；从土壤深度方向上看,五年在生水灌溉使得土壤Na含量、K含量和SAR值在不同土壤深度处变化量存在显著差异,其中,Na含量和SAR值在深层土壤的增加量高于浅层土壤,而K含量在在深层土壤的增加量低于浅层土壤,其他参数值的变化量在土壤深度方向上未出现显著差异。2、对科罗拉多、加利福尼亚和得克萨斯州的典型居民院落杂排水灌溉五年以上14种植物的生长情况以及典型景观植物和草坪样品植物叶片组织矿质含量进行分析,并和自来水灌溉样品进行比较,探讨杂排水灌溉对植物生长状况和植物组织矿质含量的影响。结果表明：(1)杂排水长期灌溉对杜松、扶芳藤、木槿、密穗蓼、菊花、圣奥古斯丁草和加州缬生长状况的影响最小,对杂排水灌溉为非常忍耐或忍耐(加州缬)；杂排水长期灌溉对德国鸢尾、李树和墨湖松生长状况的影响较小,为中度忍耐或敏感(墨湖松)；杂排水长期灌溉对苏格兰松、南非菊和柠檬生长状况的影响较大,对哈斯鳄梨生长状况的影响最大,为敏感或非常敏感(哈斯鳄梨)。(2)进一步研究表明,景观植物耐盐性和杂排水灌溉的耐受性存在显著的线性相关关系(R2=0.65)。(3)植物物种间的矿物质含量在0.05水平上差异显著,杂排水灌溉除了显著(P<0.05)影响植物组织内的Mn含量和K/Na比,对其余矿物质含量均没有显著影响。植物物种和杂排水灌溉处理之间的相互作用仅仅显著影响植物组织内的Cu、S含量和K/Na比。3、针对长期再生水灌溉的钠害问题,开展了沸石柱除钠技术研究。结果表明沸石离子交换出水中Na离子含量和SAR随着处理水量的增多而升高；且随着Na离子含量的增加,Ca离子含量减小；沸石对于原水中的K和Mg选择性相对较弱,在整个交换过程中K和Mg几乎保持不变,再生水在沸石柱中的离子交换过程实质是Ca和Na离子的等当量交换。本论文通过系统的研究表明,再生水和杂排水灌溉草坪对草坪植物和土壤性质均会产生一定的影响,在实施再生水和杂排水灌溉城市绿地的实践中应给于关注,趋利避害。更多还原

【Abstract】 Urban greens planting and maintenance consumes a lot of water, with the accelerating process of urbanization, water shortages become increasingly prominent, and reclaimed water and gray water irrigation is an important measure to alleviate the water crisis. The study on effects of recycled water and gray water irrigation on landscape plants and soil properties has important theoretical and practical value for the implementation of recycled water and gray water irrigation. Soil samples were collected and tested at different depth and periods to study changes that may occur in the soils after recycled wastewater is used for five years. Taken tap water irrigation as blank, long-term effects of Landscape irrigation using household gray water on landscape plants and mineral contents of plant tissue were studied taking tap water irrigation as control, relationship between landscape plant’s salinity tolerance and response to graywater irrigation was also compared. To ensure sustainable and affordable water supplies, it is necessary to find ways to combat sodium damage to plants if reclaimed water is to be used for long-term landscape irrigation. Zeolite column was set up to remove sodium from recycled waterf as one way to combat salinity and sodium problems associated with long-term use of recycled wastewater. The main results are as follows:1. A total of 27 soil sample sites at seven Colorado city parks were selected to study effects of five years’recycled water irrigation on soil properties, parameters of each soil sample tested included pH, Na, EC, SAR, Ca, Mg, NO3-N, P, K, OM, Zn, Fe, Mn, Cu, Cl and B. Results showed that soil Na, K, pH, SAR and EC were increased significantly after recycled water is used for five years, and Mn was decreased significantly, while OM、Ca、Mg、NO3-N、P、Zn、Fe、Mn、Cu、Cl and B didn’t change significantly. Along the depth of soil after recycled water is used for five years, variance of Na, K and SAR changed significantly, Na and SAR variance at deeper soil increased more than at above depth soil, However, the opposite trend was observed in soil K, other variance of soil parameters didn’t change significantly.2. Evaluations of existing household landscapes that have used graywater for irrigation for more than 5 years suggested that:(1) Juniper(Juniper spp), Himalayan Border Jewel (Polygonum affine), Euonymus (Euonymus spp.), Rose of Sharon (Hisbiscus syriacus), Chrysanthemum (Chrysanthemum spp.), St. Augustine grass(Stenotaphrum secundatum) and California Valeriana (Valeriana californica) to be resistant to graywater irrigation. The following plants are moderately sensitive to gray water irrigation, plum tree(Pnunus spp.), Mugo Pine(Pinus mugho) and Bearded Iris (Iris germanica); Landscape plants that are sensitive to graywater irrigation included:Scotch pine (Pinus sylvestris), Hass Avocado (Persea Americana ’Hass’), Lemon tree(Citrus limonium), and Yellow Bush Daisy (Euryops pectinatus). (2)The correlation between gray water tolerance and salinity tolerance was statistically significant (P< 0.01). The regression coefficient value (R2=0.65) suggested that approximately 65% of the variance of landscape plants’response to graywater is associated with their response to salinity, in this case, salinity tolerance. (3)Analysis of variance indicated significant plant species effect for all minerals, but no water treatment effect for all minerals except Mn and K/Na ratio. The interactions between plant species and water treatment were only significant for Cu, S and K/Na.3. Long-term reclaimed water irrigation causes sodium problems, zeolite column was usd for sodium removal from reclaimed water. The results showed that ion exchange of zeolite Na ions and SAR increases with the increase of treated water; and with the increasing content of Na ions, Ca ion content decreases; Zeolite showed pretty week selectivity for K and Mg in the raw water, K and Mg remained almost constant during the entire exchange process, Ion exchange process of reclaimed water in the zeolite column is essentially equivalent exchange between Ca and Na ions.Results of this paper showed that recycled water and gray water irrigation of city greens will have impacts on both plant itself and soil properties which should pay enough attion during the pactice of recycled water and gray water irrigation of city greens.更多还原