DFG Trilateral collaboration Deutschland-Israel-Palestine: Irrigation with municipal effluents: effects on physical soil properties, contaminant transport, soil carbon dynamics, soil microbial activity and crop quality

以色列使用处理过的废水（TWW）灌溉作物已有45年以上的历史。为了实现可持续农业和环境保护，必须考虑和评估TWW对有机质、盐类、营养物和重金属的投入以及土壤中发展的过程。在这个三边项目的第一阶段，获得了灌溉土壤中养分和重金属运输、植物吸收、土壤疏水性、土壤团聚、真菌、酶和微生物活动等过程的相关信息。田间和温室试验表明，TWW灌溉对植物重金属吸收的影响小于土壤类型。TWW的添加使土壤有机质发生改变，从而增强了土壤微生物活性。在项目的第一阶段，在加沙进行了为期两年的实地试验。此外，所有合作伙伴之间的合作是在几次科学讨论会议上建立起来的。三边项目的第二阶段将包括深入调查和继续实地试验。自2007年开始运行的一个完善的、独特的渗滤仪设备具有相同的设置，可用于第二阶段，研究在四种不同水质灌溉的不同粘土含量的土壤中疏水性、渗透性、土壤团聚体形成和微生物参数的发展。另外还将进行室内试验，以研究土壤质地、养分垂直输送和土壤水分重复发展的影响。有机物的生物稳定性将通过启动效应实验、酶谱分析和原位可视化研究，特别关注疏水土壤表面和更深的土壤层。综合分析结果将为TWW灌溉土壤中元素通量、SOM周转、生物活性和表面疏水性之间的相互作用提供新的见解。

Treated wastewater (TWW) is used since more than 45 years for irrigating crops in Israel. For sustainable agriculture and environmental conservation the input of organic matter, salts, nutrients and heavy metals with the TWW as well as the processes developing in the soil have to be considered and evaluated. In the first phase of this Trilateral project relevant information was gained about processes in irrigated soils concerning nutrient and heavy metal transport and plant uptake, soil hydrophobicity, soil aggregation, fungi, enzymes and microbial activity. It was shown with field and greenhouse experiments that the uptake of heavy metals into plants is less affected by TWW irrigation than by soil type. Soil microbial activity is enhanced by addition of TWW resulting in altered soil organic matter. In the first phase of the project the field experiment in Gaza was established and run for the duration of 2 years. Furthermore, the cooperation between all the partners was established in several meetings with scientific discussions. The second phase of the Trilateral project will consist of in-depth investigations and continuation of the field experiment. A well-established, unique lysimeter facility running since 2007 with the same setup can be used in the 2nd phase to study the development of hydrophobicity, infiltrability, soil aggregate formation and microbial parameters in soils with different clay content irrigated with four different water qualities. Additional lab experiments will be performed for the investigation of the effect of soil texture, vertical transport of nutrients and development of soil water repedency. The biological stability of organic matter will be studied with priming effect experiments, enzyme profiling and in situ visualization with special focus on the hydrophobic soil surface and deeper soil horizons. The integrative analysis of the results will provide new insights into the interactions between element fluxes, SOM turnover, biological activity and surface hydrophobicity in TWW irrigated soils.