污水灌溉对番茄生理特性及土壤环境的影响

采用日光温室研究了污水灌溉对番茄的生长发育、产量及品质的影响,探讨了Hg和As在表层土壤和番茄果实中的积累。结果表明,污水灌溉能显著促进番茄植株生物量的增加。随着时间的推移,番茄根系的密集层和根系体积有逐渐加深加大的趋势。番茄果实中各品质指标间存在显著差异,生育后期,可溶性总糖含量均比前期高。污水灌溉后土壤中Hg和As含量在不同土层差异较大,其累积顺序为As>Hg。污水灌溉条件下土壤中Hg和As含量都大于清水灌区,但污灌后果实中没有出现重金属显著偏高的现象,而且番茄果实对As吸收的选择性高于Hg。     

再生水灌溉下重金属在植物-土壤-地下水系统迁移的研究进展

再生水灌溉作为解决水资源紧缺的重要途径之一日益受到人们的重视。然而其水源中含有的重金属可能会对生态环境造成影响。回顾了国内外再生水灌溉下重金属在植物-土壤-地下水系统中的运移、分布、积累规律的研究现状与问题,在归纳分析的基础上提出了今后的研究方向。短期再生水灌溉一般不会增加植物体内重金属含量,再生水灌溉显著增加植物生物量对重金属所形成的"稀释效应"可能是其原因之一;不同的植物品种对不同重金属在植物、土壤中运移、分布和积累的影响有很大的差异;再生水短期灌溉往往不会降低土壤的环境质量,但长期灌溉再生水有可能会使土壤质量恶化,造成地下水重金属污染。     

Some environmental problems associated with the use of treated wastewater for irrigation in Jordan

Treated effluent was used for eggplant (aubergine) irrigation through a trickle system at As-Samra experimental site. The soil characteristics were determined prior to irrigation. Physical, chemical and biological characteristics of the effluent were determined during the growing season. Suitability of the effluent for irrigation was studied. The crop and soil were tested for pathogenic pollution. The accumulation of salts and heavy metals in the soil as well as concentration of the nutrients and heavy metal accumulation in the plant tissues were determined. Clogging of the irrigation system was evaluated and treated. Yield was determined.Results of the study showed that the effluent has a low heavy metal content. It showed moderate restriction for surface trickle irrigation. Regarding the microbiological quality of the treated wastewater, it was found that the faecal coliform ranged from 2.1 × 10³ to 1.8 × 10 Most Probable Number (MPN) per 100 ml at the irrigated site, while it is free from nematode eggs. The soil surface under the effluent irrigation water was found to contain faecal coliform, but the count drastically decreased with depth. Except for a very low coliform count on fruit skins, no colifonn count was found on the crop leaves, whether they were free or in contact with the soil. The effluent showed a rather high concentration of chlorophyll a due to the presence of algae. Results of soil analysis after eggplant harvest showed a slight increase in heavy metals and salt accumulation at the periphery of the wet zone. Nutrients and heavy metal concentration in eggplant tissue under treated effluent irrigation was within the normal range in agricultural crops. Although filtration of the effluent was not practised, there was minimum clogging of the irrigation system. This clogging was successfully controlled with acid and chlorine. Eggplant yield under treated effluent was twice the average eggplant production under fresh water irrigation using conventional fertiliser application in Jordan.     

再生水灌溉对紫花苜蓿产量和品质的影响

[目的]探究再生水灌溉不同因素对紫花苜蓿产量和品质的影响.[方法]通过三因素三水平正交试验,利用极差分析和方差分析,研究了再生水灌溉不同因素的主次顺序、显著性、各因素影响趋势及最优组合.[结果]灌溉定额对紫花苜蓿株高、茎粗、一级分枝数、干草产量、粗脂肪、粗纤维、酸性洗涤纤维、中性洗涤纤维、相对饲喂价值、氮、磷、钾和钙影...     

Assessing environmental impacts of reclaimed wastewater irrigation in paddy fields using bioindicator

Irrigation water quality influences many aspects of agroecosystems, but less is known about how complex microbial and biological communities respond to changing water quality due to causes such as reuse irrigation. The objectives of this study are to monitor and assess the environmental impacts of reclaimed wastewater irrigation on water quality and soil that might cause potential health hazards and to assess its agro-environmental effects. Two sites, which are irrigated by filtered wastewater after UV (Ultraviolet) treatment and from an agricultural reservoir that satisfied the agricultural water quality standards of Korea, were selected as treatment and control, respectively. The environmental impacts of irrigation water quality on paddy soil, microorganisms, and arthropods were investigated. Monitoring results for water, soil, health risks, and eco-environments of the reclaimed wastewater irrigation site demonstrated no adverse effects in the paddy field. This research showed that reclaimed wastewater irrigation did not present significant environmental risks for the rice paddy agroecosystem, although long-term monitoring is needed to fully characterize its effects.     

Olive mill wastewater irrigation of maize: Impacts on soil and groundwater

The environmental impact of irrigating a maize field with weathered olive mill wastewater (OMW) for 5 years was assessed. The use of the weathered OMW added the following concentrations of nutrients to the field: 11.8 t/ha/yr carbon, 1033 kg/ha/yr total nitrogen, 23.8 kg/ha/yr phosphorous and 4161 kg/ha/yr potassium. The maize field received 6 times more nitrogen, 50 times more potassium and 2 times less phosphorous than the recommended fertilization rates. The presence of carbon increased microbial activity for organic nitrogen breakdown and the decomposition rate of organic nitrogen. No significant increase was observed of heavy metal accumulation in the soil. Electrical conductivity in the soil remained below the salinization threshold. No direct exposure values were exceeded. No impact on groundwater quality was observed. Irrigation of crops like maize with weathered OMW could be part of a viable decentralized solution for olive mill wastewater use in areas with low organic matter and high irrigation demand.     

灌溉水质对土壤重金属含量的影响研究进展

利用污水灌溉农田既缓解水资源不足,也能促进水资源的可持续利用。不同灌溉水质会使土壤重金属发生不同程度的积累,给土壤环境质量和作物生长造成危害。本文在分析土壤中重金属来源以及重金属在土壤中形态、迁移、转化特点的基础上,重点分析了灌溉水质对土壤重金属含量特征的影响,并提出根据土壤不同重金属起始含量来制定灌溉水质有关相应标准有利于指导污水灌溉的合理进行。     

污水灌溉重金属在农田土壤中的运移分布规律研究

通过试验,研究了污水灌溉重金属(Pb,Cd,Cr,Cu)在农田土壤中的运移分布规律,其中包括重金属在土壤水平方向上的分布特征、重金属在土壤垂直方向上的分布特征以及土壤重金属迁移率。研究成果对于合理开发利用污灌水资源,减轻土壤污染,改善土壤生态环境都具有一定的参考价值。     

Spatial variability of heavy metals in irrigated alfalfa fields in the upper Rio Grande River basin

Reduced quality of wastewater discharged into the Rio Grande River is reported to be the cause of crop contamination and heavy metal transport onto fertile soils. This study was conducted to characterize Cd, Pb, Ni, Zn, Cr, and Co concentrations in two alfalfa (Medicago saliva L.) fields irrigated with river water (in Texas) or wastewater mixed with river water (in Mexico) and to examine spatial variability of acid-extractable metal deposition in soil and in uptake by alfalfa. Multiple transects were established in both fields for intensive forage collection and soil sampling to depths of 1.2 m, with spacing every 7.6 or 15.2 m. Metal concentrations rarely exceeded 20 mg kg⁻¹ with the exception of Zn. Relative metal concentrations were in the order Zn > Cr > Ni > Pb > Co > Cd in both fields, and were highly correlated with clay content within the plow zone. Linear and spherical variogram models best described surface metal deposition with spatial dependence > 100 m with regard to irrigation delivery. However, increasing metal concentrations below the plow zone at the Texas site, inconsistent geostatistical trends for soil Zn and Ni, and no association of Pb with soil texture suggested that irrigation delivery was not the exclusive transport source. Estimated metal loads from river water over a 50-year period suggested that irrigation may account for up to 31 % of surface metals. It is likely that atmospheric fallout from a local ore smelter and indigenous background levels significantly contributed to observed soil metal levels. Metal concentrations in unwashed alfalfa forage tissue were at least five times less than those in soil and showed no consistent association with soil concentrations. Metal concentrations in alfalfa forage posed no toxicity threat to animals or public health. Blending wastewaters in the Rio Grande River and canal system has diluted heavy metals to low concentrations for irrigation, but not to more stringent levels for fish and wildlife. Degraded waters could be diverted from the river and directly used for irrigation under careful water and soil management.     

再生水灌溉对黑麦草生长及重金属分布特征的影响

为了阐明再生水灌溉对重金属富集植物黑麦草生长及重金属分布特征的影响,以自来水灌溉为对照,研究了再生水灌溉下黑麦草生物量、黑麦草及土壤中重金属分布特征的变化。结果表明：再生水灌溉显著增加了黑麦草生物量,地上部、根系和总生物量分别增加了26.79%、10.55%、24.91%。再生水灌溉下,黑麦草地上部和根系中Pb、Cu、Zn、Cd的含量显著增加,土壤重金属没有积累,土壤中Pb和Zn含量降低明显。再生水灌溉显著降低土壤pH、增加土壤有机质含量会对土壤重金属的活性有一定的影响。     

Management model for decision support when applying low quality water in irrigation

Use of low quality water for irrigation of food crops is an important option to secure crop productivity in dry regions, alleviate water scarcity and recycle nutrients, but it requires assessment of adverse effects on health and environment. In the EU-project “SAFIR¹” a model system was developed that combines irrigation management with risk evaluation, building on research findings from the different research groups in the SAFIR project. The system applies to field scale irrigation management and aims at assisting users in identifying safe modes of irrigation when applying low quality water. The cornerstone in the model system is the deterministic “Plant-Soil-Atmosphere” model DAISY, which simulates crop growth, water and nitrogen dynamics and if required heavy metals and pathogen fate in the soil. The irrigation and fertigation module calculates irrigation and fertigation requirements based on DAISY's water and nitrogen demands. A Water Source Administration module keeps track of water sources available and their water quality, as well as water treatments, storage, and criteria for selection between different sources. At harvest, the soil concentrations of heavy metals and pathogens are evaluated and the risk to consumers and farmers assessed. Crop profits are calculated, considering fixed and variable costs of input and output. The user can run multiple “what-if” scenarios that include access to different water sources (including wastewater), water treatments, irrigation methods and irrigation and fertilization strategies and evaluate model results in terms of crop yield, water use, fertilizer use, heavy metal accumulation, pathogen exposure and expected profit. The management model system can be used for analysis prior to investments or when preparing a strategy for the season.     

微咸水和再生水对盆栽棉花土壤理化性质和根系的影响

为缓解华北水资源短缺问题,寻求代替水源,进行了微咸水和再生水灌溉条件下不同灌水量对盆栽棉花土壤理化性质和棉花根系影响的试验。试验设置灌水水质和灌水量2个试验因素,灌水水质设计为低、中、高矿化度微咸水和再生水,清水作为对照;灌水量设计为田间持水量的95%、85%、70%、55%。试验结果表明:微咸水和再生水处理增加土壤含盐量,微咸水处理的土壤含盐量随着矿化度的升高而增加;再生水处理提高土壤有机质和硝态氮的含量;微咸水和再生水促进棉花根系的生长,在盐分累积严重的情况下根系生长最快。     

长期再生水灌溉后土壤孔隙分布的多重分形特征

土壤结构是表征土壤质量的重要指标之一.为了定量表征长期再生水灌溉后土壤孔隙分布的非均匀性,以不同年限再生水灌溉后的土壤为研究对象,采用KYKY-2800B型扫描电子显微镜获取土壤数字图像,利用数字图像处理技术测定了土壤的孔隙分布特征,运用多重分形谱参数描述了土壤孔隙分布的非均质性,探讨了土壤孔隙分布多重分形曲线对称性的意义.结果表明:多重分形谱可以定量描述土壤孔隙分布的非均质性,土壤孔隙分布的多重分形奇异谱函数α-f(α)表现为非对称连续性分布,奇异谱宽度Δα表征了土壤孔隙分布的非均质特征,大兴区北野厂灌区农田土壤孔隙分布的多重分形谱宽度Δα普遍大于石景山衙门口灌区土壤,即具有30 a再生水灌溉历史的土壤其孔隙分布的非均匀性较50 a再生水灌溉历史的土壤孔隙分布的非均匀性大,且北野厂灌区土壤小孔隙的数目小于石景山衙门口灌区土壤小孔隙数目.多重分形参数可以作为定量表征土壤孔隙分布非均匀性的重要指标.     

不同节水灌溉模式对白茶品质及茶园土壤重金属含量的影响

为探究不同节水灌溉模式对白茶品质及茶园土壤重金属含量的影响,设计不同灌溉方式(喷灌和滴灌)和不同土壤水分控制下限(65％、75％和85％),观测白茶水浸出物、游离氨基酸、茶多酚、儿茶素等品质指标及茶园土壤铬、砷、镉、汞、铜和铅含量,同时引入投影寻踪分类模型,基于高优白茶品质和低重金属残留对节水灌溉模式进行综合评价.结果...     

石家庄污灌区污水灌溉技术的研究

分析了国内外污水灌溉的研究和发展,以石家庄市污灌区为研究对象,在分析预测未来30年污水水质水量特点的基础上,采用不同的灌水技术,利用环境容量法,分析预测了在不同务件下土壤和作物中重金属和石油类浓度的发展以及相应的污清水的灌溉需水量。针对该灌区土壤现状和污水水质特点,提出了建议的合理污水灌溉技术,以保证以土壤为中心的生态系统的可持续发展。     

Effect of different drip irrigation regimes on sugar beet (Beta vulgaris L.) yield, quality and water use efficiency in Middle Anatolian, Turkey

Agricultural production has forced researchers to focus on increasing water use efficiency by improving either new drought-tolerant plant varieties or water management for arid and semi-arid areas under water shortage conditions. A field study was conducted to determine effects of seasonal deficit irrigation on plant root yield, quality and water use efficiency (WUE) of sugar beet for a 2-year period in the semi-arid region. Irrigations were applied when approximately 50–55% of the usable soil moisture was consumed in the effective rooting depth at the full irrigation (FI) treatment. In deficit irrigation treatments, irrigations were applied at the rates of 75, 50 and 25% of full irrigation treatment on the same day. Irrigation water was applied by a drip irrigation system. Increasing water deficits resulted in a relatively lower root and white sugar yields. The linear relationship between evapotranspiration and root yield was obtained. Similarly, WUE was the highest in DI25 irrigation conditions and the lowest in full irrigation conditions. According to the averaged values of 2 years, yield response factor (k _y ) was 0.93 for sugar beet. Sugar beet root quality parameters were influenced by drip irrigation levels in both years. The results revealed that irrigation of sugar beet with drip irrigation method at 75% level (DI25) had significant benefits in terms of saved irrigation water and large WUE, indicating a definitive advantage of deficit irrigation under limited water supply conditions. In an economic viewpoint, 25% saving of irrigation water (DI25) caused 6.1% reduction in the net income.     

Effects of untreated and treated wastewater irrigation on some chemical properties of cauliflower (Brassica olerecea L. var. botrytis) and red cabbage (Brassica olerecea L. var. rubra) grown on calcareous soil in Turkey

The use of wastewater for irrigation is increasingly being considered as a technical solution to minimize soil degradation and to restore nutrient content of soils. The aims of this study were to test if wastewater irrigation could improve soil fertility without affecting the quality of soils and plants. A field experiment was conducted in 2006 to investigate the effects of irrigation with untreated, and preliminary and primary treated wastewater on macro- and micronutrient distribution within the soil profile, yield and mineral content of cauliflower and red cabbage plants grown on a calcareous Aridisol in eastern Anatolia, Erzurum province, Turkey. Wastewater irrigation affected significantly soil chemical properties in the 0–30 cm soil layer and plant nutrient content after harvest. Application of wastewater increased soil salinity, organic matter, exchangeable Na, K, Ca, Mg, plant available phosphorus and microelements, and decreased soil pH. Wastewater irrigation treatments also increased the yield as well as N, P, K, Ca, Mg, Na, Fe, Mn, Zn, Cu, Pb, Ni and Cd contents of cauliflower and red cabbage plants. The highest yield, macro- and micronutrient uptake of cauliflower and red cabbage plants were obtained with the untreated wastewater. Undesirable side effects such as heavy metal contamination in soil and plant, and salinity were not observed with the application of wastewater. It can be concluded that untreated wastewater can be used confidently, in the short term, in agricultural land, while primary treated wastewater can be used in sustainable agriculture in the long term.     

Faecal contamination and hygiene aspect associated with the use of treated wastewater and canal water for irrigation of potatoes (Solanum tuberosum)

Clean water has become one of the main limiting factors in agricultural food production in Europe, especially for countries around the Mediterranean, who now face more severe and frequent seasonal water shortages. In order to overcome water shortages the European Water Framework Directive encourages and promotes the use of treated urban wastewater in agriculture. However, the use of poor quality water in agriculture poses potential health risks. The application of wastewater through subsurface drip irrigation lines could possibly overcome public health concerns by minimizing contact with wastewater by farmers, farm workers but it is uncertain if the risk for consumers of wastewater irrigated produces would be acceptable. The objective of the current study was therefore to assess whether subsurface irrigation of potatoes with low quality water was associated with higher food safety and reduced human health risks as compared with surface irrigation. The microbial quality of soil and potatoes irrigated by sprinkler, furrow and subsurface drip irrigation, using treated urban wastewater, canal water and tap water were compared at experimental sites near Belgrade, Serbia and in Bologna, Italy. Water, soil and potato samples were collected from March 2007 to September 2008 and their faecal contamination estimated by enumeration of the faecal indicator Escherichia coli. In addition, water and potatoes in Italy were analysed for the presence of helminth eggs, another important indicator of faecal pollution. A quantitative microbial risk assessment (QMRA) model combined with Monte Carlo simulations was used to assess whether the different irrigation practices and associated health risks complied with guidelines set by the World Health Organization (WHO). The study found low levels of E. coli in irrigation water (Italy mean value: 1.7 colony forming units (cfu)/ml and Serbia 11 cfu/ml), as well as in soil (Italy mean: 1.0 cfu/g and Serbia 1.1 cfu/g). Similar low concentrations of E. coli were found on potatoes (Italy mean: 1.0 cfu/g and Serbia 0.0 cfu/g). The vast majority (442/516) of the collected different samples were free of E. coli. No helminth eggs were found in any types of irrigation water or on the surface of potatoes. The risk assessment models found the use of treated wastewater to exceed the levels of risks for gastro-intestinal disease (1.0 × 10⁻³ disease risk) as recommended by the World Health Organization (WHO) for the accidental ingestion of soil by farmers (Serbia: 0.22 and Italy: 5.7 × 10⁻²). However, samples that exceeded disease risks set by the WHO were collected before initiation of wastewater irrigation and were limited to a few numbers of samples, which would indicate environmental contamination not linked to irrigation practice. Disease risk from consumption of potatoes in Italy and in Serbia was found to be within acceptable levels. No relationship was found between E. coli concentrations in irrigation water, soil and produce. Similar lack of association was found for E. coli findings in sprinkler, furrow or subsurface drip irrigated soils and produce. This indicates that subsurface drip irrigation can be practiced while ensuring food safety and protecting the health of consumers and farmers.     

Evaluation of the influence of irrigation methods and water quality on sugar beet yield and water use efficiency

Rapid urbanization and industrialization have increased the pressure on limited existing fresh water to meet the growing needs for food production. Two immediate responses to this challenge are the efficient use of irrigation technology and the use of alternative sources of water. Drip irrigation methods may play an important role in efficient use of water but there is still limited information on their use on sugar beet crops in arid countries such as Iran. An experiment was conducted to evaluate the effects of irrigation method and water quality on sugar beet yield, percentage of sugar content and irrigation water use efficiency (IWUE). The irrigation methods investigated were subsurface drip, surface drip and furrow irrigation. The two waters used were treated municipal effluent (EC = 1.52 dS m⁻¹) and fresh water (EC = 0.509 dS m⁻¹). The experiments used a split plot design and were undertaken over two consecutive growing seasons in Southern Iran. Statistical testing indicated that the irrigation method and water quality had a significant effect (at the 1% level) on sugar beet root yield, sugar yield, and IWUE. The highest root yield (79.7 Mg ha⁻¹) was obtained using surface drip irrigation and effluent and the lowest root yield (41.4 Mg ha⁻¹) was obtained using furrow irrigation and fresh water. The highest IWUE in root yield production (9 kg m⁻³) was obtained using surface drip irrigation with effluent and the lowest value (3.8 kg m⁻³) was obtained using furrow irrigation with fresh water. The highest IWUE of 1.26 kg m⁻³ for sugar was obtained using surface drip irrigation. The corresponding efficiency using effluent was 1.14 kg m⁻³. Irrigation with effluent led to an increase in the net sugar yield due to an increase in the sugar beet root yield. However, there was a slight reduction in the percentage sugar content in the plants. This study also showed that soil water and root depth monitoring can be used in irrigation scheduling to avoid water stress. Such monitoring techniques can also save considerable volumes of irrigation water and can increase yield.     

Soil surface water repellency induced by treated wastewater irrigation: physico-chemical characterization and quantification

Irrigation with treated wastewater (TWW) is commonly practiced in Israel to relieve freshwater (FW) shortages. We hypothesized that the organic matter (OM) originating from TWW irrigation alters the physico-chemical properties of the soil, induces water repellency in the soil’s top layer, and consequently alters water distribution in the soil profile. In measurements taken in an avocado orchard on a clayey soil, water repellency was found in TWW-irrigated plots. In addition, smaller wetted surface areas were recorded around the drippers in comparison with FW drippers. Drier zone below soil surface was observed in TWW-emitting drippers. OM extraction from the different plots exhibited differences in quantity and quality of organic substances between TWW- and FW-irrigated soils, with a higher quantity of hydrophobic substances in the TWW-irrigated soil extract.