Irrigation water resource management: 'IW-QC2' software tool

This software tool (in Microsoft Excel) ‘Irrigation water quality and quantity for covered crops’ (or ‘IW-QC2’) was developed for application by water resource managers and the horticulture industry to facilitate decision-making on water resource selection, water storage capacities and quality of blended supply water. This time series climate-based modelling tool developed to assess the quantity and quality of irrigation water management options that can be achieved by blending of different water sources. These include harvested stormwater, recycled water, local river and ground waters. This tool was initially developed for soil-based greenhouse crops (i.e. tomato, cucumber, capsicum and eggplant) commonly grown in the NAP region but can be modified to include other covered crops. The modelled surface water supply availabilities (volumes and quality) can be calculated from historical climate data or future climate predictions. Predicted volumes of water that could be harvested from the greenhouse roofs (with user selected climate models) can be used when it is available (during the wet season) to minimize the water storage requirements or can be stored and used to blend with other water sources to achieve fit-for purpose water qualities (e.g. TDS level) during a specific growth stage of a crop. Two modelling scenarios were developed for harvested roof runoff 1) use when available and 2) storage and reuse when needed to achieve target water quality within a blended water supply. IW-QC2 tool output includes the determination of the amount and quality of irrigation blended waters for soil-based crops and when desalination (reverse osmosis, RO) is required, based on the trigger values for TDS and chloride concentrations for irrigation water.本基于Microsoft Excel开发的软件工具名为《设施作物灌溉水水质与水量测算工具》（简称'IW-QC2'），专为水资源管理者与园艺行业开发，用于辅助其开展水资源选型、储水容量规划与混合供水水质优化等决策工作。该工具属于基于气候的时序建模工具，旨在评估通过混合多种水源可实现的灌溉水管理方案的水量与水质，适配水源包括收集的雨水、再生水、本地地表水与地下水。本工具最初针对NAP地区常见的土培温室作物（如番茄、黄瓜、甜椒与茄子）开发，也可经修改适配其他设施作物。可基于历史气候数据或未来气候预测，测算得到模拟的地表水供水量（含水量与水质）。借助用户选定的气候模型，可预测温室屋顶可收集的雨水量：在雨季可直接取用以降低储水需求，也可将其储存后与其他水源混合，在作物特定生长阶段调配出适配用途的水质（如总溶解固体（Total Dissolved Solid, TDS）浓度）。针对屋顶收集径流，工具设置了两种建模场景：1）实时取用（水源充足时）；2）按需储存复用，以在混合供水体系中达成目标水质。IW-QC2的输出结果包括：针对土培作物的混合灌溉水水量与水质测算，以及基于灌溉水总溶解固体与氯离子浓度触发阈值，判断是否需要开展脱盐（反渗透，Reverse Osmosis, RO）处理。