Quantity- and Quality-Based Farm Water Productivity in Wine Production: Case Studies in Germany

Water use indicators at farm scale - An agro-hydrological software solution

The challenge to sustainably intensify agricultural production in farming systems in face of the increasing variability in regional water resources requires concerted action from many stakeholders, locally, regionally and globally. Models, such as the AgroHyd Farmmodel presented here, can provide information on how farm management decisions affect local water resources at various scales for use in multiple assessment frameworks. It is a stand-alone web-based software that connects agricultural and water-related systems, including all water flows related to farming systems. Results from a case study of the production of 12 crops with rainfed and supplemental irrigation on a farm in northeastern Germany are described here. Indicators that relate the water use to plant production on the farm such as water intensity or water productivity are compared in detail for three consecutive years with greatly varying annual rainfall amounts (from 373 to 790 mm) to highlight the effect of local variability on water flows and indicator values. The discussion illustrates how information on the effect of management decisions, such as crop type, seeding date, crop rotation, cultivation and irrigation on water use can be processed into indicators to help farmers make more effective decisions.

Farm Water Productivity in Conventional and Organic Farming: Case Studies of Cow-Calf Farming Systems in North Germany

The increase of organic agriculture in Germany raises the question of how water productivity differs from conventional agriculture. On three organic and two conventionally farming systems in Germany, water flows and water related indicators were quantified. Farm water productivity (FWP), farm water productivity of cow-calf production (FWPlivestock), and farm water productivity of food crop production (FWPfood crops) were calculated using the modeling software AgroHyd Farmmodel. The FWP was calculated on a mass and monetary basis. FWPlivestock showed the highest productivity on a mass basis occurring on a conventional farm with 0.09 kg m−3Winput, whereas one organic farm and one conventional farm showed the same results. On a monetary basis, organic cow-calf farming systems showed the highest FWPlivestock, with 0.28 € m−3Winput. Since the productivity of the farm depends strongly on the individual cultivated plants, FWPfood crops was compared at the level of the single crop. The results show furthermore that even with a precise examination of farm water productivity, a high bandwidth of temporal and local values are revealed on different farms: generic FWP for food crops and livestock are not within reach.