Effects of water-saving superabsorbent polymer on antioxidant enzyme activities and lipid peroxidation in oat (Avena sativa L.) under drought stress

BACKGROUND: Drought stress significantly limits oat (Avena sativa L.) growth and productivity. Thus an efficient management of soil moisture and study of metabolic changes in response to drought are important for improved production of oat. The objective was to gain a better understanding of drought tolerance mechanisms and improve soil water management strategies using water‐saving superabsorbent polymer (SAP) at 60 kg ha^?1 under three irrigation levels (adequate, moderate and deficit) using a new type of hydraulic pressure‐controlled auto irrigator. RESULTS: The results showed that the relative water content and leaf water potential (ψ₁) were much higher in oats treated with SAP. Although the SAP had little effect on plant biomass accumulation under adequate and moderate irrigation, it significantly increased the biomass by 52.7% under deficit irrigation. Plants treated with SAP under deficit irrigation showed a significant decrease in superoxide dismutase, catalase, peroxidase, ascorbate peroxidase and glutathione reductase activities in leaves compared with control plants. CONCLUSION: Our results suggested that drought stress leads to production of oxygen radicals, which results in increased lipid peroxidation and oxidative stress in the plant, and the application of SAP could conserve soil water, making same available to plants for increased biomass accumulation and reduced oxidative stress especially under severe water stress. Copyright © 2010 Society of Chemical Industry     

基于农田灌溉的城市污水再生利用贮存技术研究

为充分利用再生水资源,将城市污水回用于农田灌溉,研究了城市污水再生水贮存技术。明确提出了城市污水再生水贮存的可行性,主要有机污染物COD、BOD5、凯氏氮、pH、硫化物、细菌等随时间与贮存池水深的变化规律;提出采用二次加氯的原理解决硫化物、细菌等超标的方法,具有广泛的适用性。     

干湿田面糙率差异对灌溉模拟效果影响

田面糙率是影响畦灌水流运动过程的关键参数,其值的合理确定对灌溉模拟效果影响显著.本文基于田间实测数据,借助地面灌溉模拟模型,分析不同土质、入畦流量和坡度条件下考虑与不考虑干湿田面糙率差异对灌溉模拟效果的影响.结果表明,考虑干湿差异的模拟效果略优于不考率干湿差异的模拟效果,且通过敏感性分析得出,湿面糙率起决定性作用,干面糙率影响较小.该结果可为地面灌溉反馈控制系统中田面糙率系数的合理确定提供科学依据.     

EFFECT OF GROUNDWATER TABLE CONTROL ON WATER SAVING IRRIGATION STRATEGIES IN THE QINGTONGXIA IRRIGATION DISTRICT

This paper focuses on the analysis of the effects of groundwater table control under different irrigation water amounts on the water and salinity balance and on crop yield. Two experimental areas, the Pingluo and Huinong experimental sites, were selected to collect the required data. The agro-hydrological model Soil Water-Atmosphere-Plant (SWAP) was used to analyse the water flows and salt transport processes for different groundwater levels and irrigation scenarios. Six scenarios, which resulted from different groundwater table regimes combined with different irrigation amounts, were simulated. The results show that high groundwater tables due to the excessive irrigation are the main cause of the large amount of drainage water and low crop yield;reducing irrigation water without a lower groundwater table will not lead Io a large reduction of the drainage water, and will reduce the crop yield even more; to lower the groundwater table is a good measure to control the drainage water and increase crop yield.     

农田水利灌溉管理存在的问题及对策

本文分析了农田水利灌溉的基本要求,加强农田水利灌溉管理的意义,进而分析了农田水利灌溉管理存在的问题。为了改善农田水利灌溉工程,构建科学合理的管理模式是有必要的,要健全农田水利灌溉管理制度,加大灌溉工程管理资金投入,使农田水利灌溉得到很好的利用。     

Smart meter enabled disaggregation of urban peak water demand: precursor to effective urban water planning

The implementation of a smart water metering system in Hervey Bay in 2006–2007 allowed the local water utility to record the hourly water consumption of all its customers. This data availability has enabled a large scale research project to proceed with the aim to disaggregate peak hour, peak day and peak month demand in the water distribution network into primary indoor usage (e.g. shower, washing machine, etc.) and irrigation components. Such information can guide the development of alternative tariff structures and other demand management initiatives aimed at reducing peak demand. This paper details results of the analyis of average hour, peak hour, peak day and peak month consumption data of 2884 residential customers selected from four District Metered Areas (DMAs) located in the city of Hervey Bay in Queensland, Australia.     

吸收国外先进经验加快河北省节水灌溉的发展

水资源紧缺已是影响河北省乃至全国经济发展的重要因素，节水灌溉势在必行。学习国外先进的节水灌溉技术和管理方法，总结节水灌溉事业的经验，对河北省农业结构调整和水资源可持续发展提供参考和建议。     

PLC在苗圃节水灌溉中的应用

本文介绍了苗圃节水灌溉自动监控系统的工作原理,及PLC在该系统中的应用。