Numerical Analysis to Investigate the Effects of the Design and Installation of Equilibrium Tension Plate Lysimeters on Leachate Volume

ABSTRACT steel porous plates. Various control options for the ten-The composition and quantity of leachate as it moves down through sion applied to these porous plates have been advocated. the vadose zone is seldom measured directly because sampling in this The simplest being zero tension, where no capacity to unsaturated zone at the depths required has proven to be extremely exert a tension on the plates exists. The zero-tension difficult. A promising technique is the use of large porous plates lysimeters rely on the formation of a saturated zone known as equilibrium tension plate lysimeters (ETPLs), which have a controlled suction exerted on them that mimics the soil matric potential measured in the surrounding undisturbed soil profile. In the design phase for the installation of 15 ETPLs at five different depths (three replicates) around a central access chamber in the vadose zone in the Lake Taupo catchment of New Zealand, questions arose regarding the effects of the design and installation layout of the ETPLs above the plate before water can be collected and sam-pled. The requirement of this saturated zone for sam-pling is an artifact of the measurement technique an

A review of modelling tools for implementation of the EU Water Framework Directive in handling diffuse water pollution

A numerical catchment-scale model capable of simulating diffuse water pollution is necessary in sustainable environmental management for better implementation of the EU Water Framework Directive. This paper provides critical reviews of most popular and free models for diffuse water modelling, with detailed sources and application potential. Based upon these reviews, further work of selecting and testing the HSPF model was carried out, with a case study in the Upper Bann Catchment, Northern Ireland. The calibrated and validated HSPF model can well represent the characteristics of surface water quantity and quality. Climate change scenario evaluation in 5 years showed that when the annual mean temperature increase 3◦C the mean yearly total runoff volume will decrease by 11.1% and the mean daily river flow 11.4%. If 20% crop and pasture land is converted into forest land in the study area, the mean river concentration of nitrate, nitrite, NH4 and PO4 in 5 years will decrease by 19.4%, 33.3%, 31.3% and 31.3% respectively. When applying filter strip method in 80% crop and pasture land in the area, the reduction of the mean concentration of nitrate, nitrite, NH4 and PO4 in 5 years will be 15.3%, 33.3%, 31.3%, and 5.6% respectively. This study shows that HSPF is a suitable model in handling diffuse source water pollution, which can be introduced into the Programme of Measures in the River Basin Management Plans for better implementation of the EUWFD