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- ItemWater use indicators at farm scale: Methodology and case study(Hoboken, NJ : Wiley-Blackwell Publishing Ltd, 2012) Prochnow, A.; Drastig, K.; Klauss, H.; Berg, W.Indicators for water use at farm scale can assist farmers in understanding the water flows on their farms and in optimizing water use by adapting agronomic measures and farm management. The objective of this work is to develop a methodology to estimate water flows at the farm scale, to derive indicators for farm water use, and to apply them in a first case study. After the spatial and temporal boundaries of the farm system and the water flows are defined, three indicators to assess water use at the farm scale are developed: farm water productivity, degree of water utilization, and specific inflow of technical water. Farm water productivity describes the ratio of farm output to water input, where the water input is the total of those water inflows into the farm system that can be assigned to the generation of farm output. Farm output is expressed on a mass basis, food energy basis, and monetary basis. The degree of water utilization characterizes the relationship between productive water to the total water inflow into the farm system, where productive water comprises those water flows that directly contribute to biomass generation via plant and animal metabolism. The specific technical water inflow quantifies the water inflow into the system by technical means relative to the farm area. The application of the methodology in a first case study for a mixed crop-livestock farm with 2869 ha in Germany results in a farm water productivity of 2.30 kg fresh mass per mWinput-3, 1.03 kg dry mass per m Winput-3, 5.96 GJ m Winput-3, and 0.25 € mWinput-3. The degree of water utilization is 0.56. The specific technical water inflow is 36.5 m3 ha-1 year -1. Factors that mainly effect these indicators and general approaches to optimize water use in farms are discussed as well as the further research required for practical implementation.
- ItemWater productivity of poultry production: The influence of different broiler fattening systems(Malden, Mass. : Wiley, 2015) Krauß, Michael; Keßler, Jens; Prochnow, Annette; Kraatz, Simone; Drastig, KatrinWith the expected increase in poultry meat consumption water use will increase as well. The objective of this study is to quantify the effects of fattening systems on the water productivity in broiler chicken production with consideration given to conditions in Germany. Four fattening systems were analyzed in terms of water use for feed production, drinking, cleaning, and the parent stock. The fattening systems differed in intensity, ranging from fast fattening with a fattening period of 30 days and a carcass weight of 1.1 kg to slow fattening with a period up to 46 days and a carcass weight of 2.1 kg. During the fattening period the broiler chicken were fed with performance-linked feed. The water productivity of the feed components varied from 0.4 kg dry mass per m3 water input for soybean meal to 1.8 kg dry mass per m3 water input for maize. In all fattening systems the water input for feed production accounted for 90 to 93% of the total water input. The share for the parent stock was 7 to 10%, while drinking and cleaning water accounted for less than 1%. For all fattening systems the water productivity was 0.3 kg carcass weight per m3 water input, 2.8 MJ food energy per m3 water input and 57 g food protein per m3 water input. The shorter fattening period and lower feed demand in the more intensive fattening systems were juxtaposed to the higher carcass weight and higher water productivity of the feed components in the more extensive systems.
- ItemQuantity- and Quality-Based Farm Water Productivity in Wine Production: Case Studies in Germany(Basel : MDPI, 2017-2-1) Peth, Denise; Drastig, Katrin; Prochnow, AnnetteThe German wine sector has encountered new challenges in water management recently. To manage water resources responsibly, it is necessary to understand the relationship between the input of water and the output of wine, in terms of quantity and quality. The objectives of this study are to examine water use at the farm scale at three German wineries in Rhenish Hesse, and to develop and apply, for the first time, a quality-based indicator. Water use is analyzed in terms of wine production and wine-making over three years. After the spatial and temporal boundaries of the wineries and the water flows are defined, the farm water productivity indicator is calculated to assess water use at the winery scale. Farm water productivity is calculated using the AgroHyd Farmmodel modeling software. Average productivity on a quantity basis is 3.91 L wine per m3 of water. Productivity on a quality basis is 329.24 Oechsle per m3 of water. Water input from transpiration for wine production accounts for 99.4%-99.7% of total water input in the wineries, and, because irrigation is not used, precipitation is the sole source of transpired water. Future studies should use both quality-based and mass-based indicators of productivity. © 2017 by the authors.
- ItemFarm water productivity in conventional and organic farming: Case studies of cow-calf farming systems in North Germany(Basel : MDPI AG, 2018) Vellenga, L.; Qualitz, G.; Drastig, K.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.