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Drainage and agricultural use transform natural peatlands from a net carbon (C) sink to a net C source. Rewetting of peatlands, despite of high methane (CH4) emissions, holds the potential to mitigate climate change by greatly reducing CO2 emissions. However, the time span for this transition is unknown because most studies are limited to a few years. Especially, nonpermanent open water areas often created after rewetting, are highly productive. Here, we present 14 consecutive years of CH4 flux measurements following rewetting of a formerly long-term drained peatland in the Peene valley. Measurements were made at two rewetted sites (non-inundated vs. inundated) using manual chambers. During the study period, significant differences in measured CH4 emissions occurred. In general, these differences overlapped with stages of ecosystem transition from a cultivated grassland to a polytrophic lake dominated by emergent helophytes, but could also be additionally explained by other variables. This transition started with a rapid vegetation shift from dying cultivated grasses to open water floating and submerged hydrophytes and significantly increased CH4 emissions. Since 2008, helophytes have gradually spread from the shoreline into the open water area, especially in drier years. This process was periodically delayed by exceptional inundation and eventually resulted in the inundated site being covered by emergent helophytes. While the period between 2009 and 2015 showed exceptionally high CH4 emissions, these decreased significantly after cattail and other emergent helophytes became dominant at the inundated site. Therefore, CH4 emissions declined only after 10 years of transition following rewetting, potentially reaching a new steady state. Overall, this study highlights the importance of an integrative approach to understand the shallow lakes CH4 biogeochemistry, encompassing the entire area with its mosaic of different vegetation forms. This should be ideally done through a study design including proper measurement site allocation as well as long-term measurements.

Greenhouse gas emissions (GHG), as well as other gaseous emissions and agronomic variables were continuously measured for three years (2011/2012 – 2014/2015) at eight experimental field sites in Germany. All management activities were consistently documented. The GHG-DB-Thuenen stores these multi-variable data sets of gas fluxes (CO2, N2O, CH4 and NH3), crop parameters (ontogenesis, aboveground biomass, grain and straw yield, N and C content, etc.), soil characteristics (nitrogen content, NH4-N, NO3-N, bulk density etc.), continuously recorded meteorological variables (air and soil temperatures, radiation, precipitation, etc.), management activities (sowing, harvest, soil tillage, fertilization, etc.), and its metadata (methods, further information about variables, etc.). In addition, NOx data were measured and analyzed. Also available are site-specific calculated C and N balances for the respective crops and crop rotations.

Winter oilseed rape (WOSR) is the major oil crop cultivated in Europe and the most important feedstock for biodiesel. Up to 90% of the greenhouse gas (GHG) emissions from biodiesel production can occur during oilseed rape cultivation. Therefore, mitigation strategies are required and need to focus on direct nitrous oxide (N2O) emission as one of the largest GHG contributors in biodiesel production. Earlier studies show that nitrification inhibitors (NIs) can reduce N2O emissions derived from N-fertilization. Since information on the effect of biogas digestates with or without NIs on N2O emissions from WOSR fields is scarce, the aim of this study was to evaluate their effects on N2O emissions, mineral N dynamics, and oil yield in WOSR production fertilized with digestate. The study was conducted at five sites across Germany over three years resulting in 15 full site-years data sets. Across all sites and years, N2O emission from WOSR fertilized with biogas digestate (180 kg NH4+-N ha−1yr−1) ranged between 0.2 and 3.5 kg N2O–N ha−1 yr−1. Due to the reduction of the nitrate concentrations following digestate application, application of NI significantly reduced annual N2O emission by 36%. Our results demonstrate that NI can be an effective measure for reducing N2O emissions from digestate application, but its effectiveness depends on soil and weather conditions, and ultimately on the site-specific potential for N2O production and release. There was no effect of NI application on grain and oil yield.

Oilseed rape (Brassica napus L.) is the major oil crop in Europe and Germany but its hydrological functioning is poorly understood. Studies on the interception processes in oilseed rape have been lacking until the present. The interception of rainfall by oilseed rape is expected to vary in response to substantial changes in canopy structure throughout the cropping cycle and fertilization treatment. To determine evaporation of intercepted water, field measurements of a winter oilseed rape crop were conducted for different stages of development and five treatments of fertilization (0, 60, 120, 180 and 240 kg N/ha). Precipitation (P) and throughfall (TF) were measured hourly, along with vegetation structure measurements of the leaf area index (LAI). A range of 0–21% for the percentage of stemflow (SF) of P was estimated from soil moisture measurements. For the vegetation period from March to June the cumulative P of 112 mm was converted into 49 mm TF (44%). The inferred evaporation of intercepted water (I) was 63 mm (56%). There was a gradual and clear increase in I from 45% to 67%, reflecting the increasing fertilization treatments. Hence, less soil water was available with increasing amounts of fertilization, since the water fraction evaporating from the canopy increases. Plant architecture, LAI and meteorological conditions during the cropping cycle appeared to be the main factors determining I. For irrigation planning and water use, studies of the evaporation of intercepted water must be considered.

Detailed knowledge about farm management practices and related hydrological processes on water productivity is required to substantially increase the productivity of precipitation water use in agriculture. With this in mind, the effect of the nitrogen (N) fertilization level on water productivity of winter oilseed rape (Brassica napus L.) was analyzed using a modeling approach and field measurements. In this first study of interception loss and water productivity in winter oilseed rape, the crop was cultivated in a field experiment on a sandy soil in Brandenburg (Germany) under five nitrogen fertilization treatments with 0, 60, 120, 180, and 240 kg mineral N ha−1 a−1. Based on data from three vegetation periods the water flows and the mass-based water productivity of seeds were calculated on a daily basis with the AgroHyd Farmmodel modeling software. As recommended from the recently developed guidelines of the FAO on water use in agriculture, the method water productivity was applied and uncertainties associated with the calculations were assessed. Economic profit-based water productivity (WPprofit) was calculated considering the costs of fertilization and the optimal level of N fertilization, which was determined based on a quadratic crop yield response function. Mean water productivity of seeds varied from 1.16 kg m−3 for the unfertilized control sample to 2.00 kg m−3 under the highest fertilization rate. N fertilization had a clearly positive effect on WPprofit. However, fertilizer application rates above 120 kg N ha−1 a−1 led to only marginal increases in yields. Water productivity of seeds under the highest fertilization rate was only insignificantly higher than under medium application rates. The optimum N level for the maximal WPprofit identified here was higher with 216 kg N ha−1 a−1. The conclusion is that further research is needed to investigate the interaction between fertilization and other farm management practices.

The production of broiler meat has increased significantly in the last decades in Germany and 3 worldwide, and is projected to increase further in the future. As the number of animals raised 4 increases, so too does the amount of manure produced. The identification of manure treatment options 5 that cause low greenhouse gas emissions becomes ever more important. This study compares four 6 treatment options for broiler manure followed by field spreading: storage before distribution,7 composting, anaerobic digestion in a biogas plant and production of biochar. For these options 8 potential direct and indirect greenhouse gas emissions were assessed for the situation in Germany. 9 Previous analyses have shown that greenhouse gas balances of manure management are often strongly 10 influenced by a small number of processes. Therefore, in this study major processes were represented 11 with several variants and the sensitivity of model results to different management decisions and 12 uncertain parameters was assessed. In doing so, correlations between processes were considered, in 13 which higher emissions earlier on in the process chain reduce emissions later. The results show that 14 biogas production from broiler manure leads to the lowest greenhouse gas emissions in most of the 15 analysed cases, mainly due to the emission savings related to the substitution of mineral fertilizers and 16 the production of electricity. Pyrolysis of the manure and subsequent field spreading as a soil 17 amendment can lead to similarly low emissions due to the long residence time of the biochar, and may 18 even be the better option than poorly managed biogas production. Composting is the treatment option 19 resulting in highest emissions of greenhouse gases, due to high ammonia volatilization, and is likely 20 worse than untreated storage in this respect. These results are relatively insensitive to the length of 21 transport required for field spreading, but high uncertainties are associated with the use of emission 22 factors.

Winter oilseed rape (Brassica napus L., WOSR) is the major oil crop cultivated in Europe. Rapeseed oil is predominantly used for production of biodiesel. The framework of the European Renewable Energy Directive requires that use of biofuels achieves GHG savings of at least 50% compared to use of fossil fuel starting in 2018. However, N2O field emissions are estimated using emission factors that are not specific for the crop and associated with strong uncertainty. N2O field emissions are controlled by N fertilization and dominate the GHG balance of WOSR cropping due to the high global warming potential of N2O. Thus, field experiments were conducted to increase the data basis and subsequently derive a new WOSR-specific emission factor. N2O emissions and crop yields were monitored for three years over a range of N fertilization intensities at five study sites representative of German WOSR production. N2O fluxes exhibited the typical high spatial and temporal variability in dependence on soil texture, weather and nitrogen availability. The annual N2O emissions ranged between 0.24 kg and 5.48 kg N2O-N ha−1 a−1. N fertilization increased N2O emissions, particularly with the highest N treatment (240 kg N ha−1). Oil yield increased up to a fertilizer amount of 120 kg N ha−1, higher N-doses increased grain yield but decreased oil concentrations in the seeds. Consequently oil yield remained constant at higher N fertilization. Since, yield-related emission also increased exponentially with N surpluses, there is potential for reduction of the N fertilizer rate, which offers perspectives for the mitigation of GHG emissions. Our measurements double the published data basis of annual N2O flux measurements in WOSR. Based on this extended dataset we modeled the relationship between N2O emissions and fertilizer N input using an exponential model. The corresponding new N2O emission factor was 0.6% of applied fertilizer N for a common N fertilizer amount under best management practice in WOSR production (200 kg N ha−1 a−1). This factor is substantially lower than the linear IPCC Tier 1 factor (EF1) of 1.0% and other models that have been proposed.

The foetal environment is filled with a variety of noises. Among the manifold sounds of the maternal respiratory, gastrointestinal and cardiovascular systems, the intonation properties of the maternal language are well perceived by the foetus, whose hearing system is already functioning during the last trimester of gestation. These intonation (melodic) features, reflecting native-language prosody, have been found to shape vocal learning. Having had ample opportunity to become familiar with their mother’s language in the womb, newborns have been found to exhibit salient pitch-based elements in their own cry melodies. An interesting issue is whether an intrauterine exposure to a maternal pitch accent language, such as Swedish, in which emphatic syllables are pronounced typically on a higher pitch relative to other syllables will affect newborns’ cry melody (fundamental frequency contour). The present study aimed to answer this question by quantitatively analysing and comparing the melody structure in 52 Swedish compared with 79 German newborns. In accordance with previous approaches, cry melody structure was analysed by calculating a melody complexity index (MCI) expressing the share of cries exhibiting two or more (well-defined) arc-like substructures uttered during the recording sessions. A low MCI reflects a dominance of cries with a ‘simple’, i.e. single-arc melody. A significantly higher MCI was found in the Swedish infant group, which further corroborates the assumption that the well-known foetal sensitivity for musical (melodic) stimuli seems to shape infants’ cry melody.

This study examines the inter-annual variability of production data in an organic dairy farm and its effect on the estimation of product-related greenhouse gas emissions (GHG) using a detailed material flow model. It is believed that the examination of only one production year may not adequately reflect temporal representativeness and may therefore lead to unreliable results. The current study also provides a method to deal with variability when temporal representativeness cannot be ensured. All material flows related to milk production from six consecutive milk years in an organic dairy farm in northern Germany were analysed. The milk yield of the 75 to 91 cows varied between 5418 and 7102 kg energy corrected milk (ECM) per cow and year. GHG emissions were estimated using calculation guidelines from the International Dairy Federation (IDF) and the Intergovernmental Panel on Climate Change (IPCC). Emissions were calculated in the Flow Analysis and Resource Management (FARM) model ensuring mass balances for nitrogen and phosphorous in every subsection of the model. Based on the variability of crop yields, the number of years for representative average data was calculated as well as an uncertainty when only a limited number of years was available. Estimated GHG emissions varied between 0.88 and 1.09 kg CO2-eq kg−1 ECM−1 (mean, standard deviation of the mean = 0.97 and 0.07 kg CO2-eq kg−1 ECM−1). Emissions from ruminant digestion had the highest contribution (50.9 ± 2.3) percent in relation to overall product-related GHG emissions. Direct emissions from soil showed the highest coefficient of variation (36%) due to simultaneous changes in fertilization amount, crop yield and milk yield which showed no significant direct relationship. The number of years needed to be assessed for representative average yields was between 27 and 215 years for clover grass and maize silage, respectively. When performing a sensitivity analysis based on the variability of crop yields, the assessed farm showed reliable results with average data of at least 4 years. Temporal representativeness should be dealt with explicitly in GHG assessments for dairy farming. If the representativeness of crop yields cannot be ensured, an uncertainty bandwidth of the results based on variability of yields can provide a basis for comparing different farms or farming systems. This approach could also be extended to other variabilities in dairy farming for more reliability of results.

Grain moisture content is an important factor for the management of harvesting and postharvest operations and for capacity planning in grain harvest, storage and preservation, and a basis for pricing in grain trade. The advantage of rapid and non-destructive on-combine moisture content determination is set against the disadvantage of lower measurement accuracy. The objectives of this study are to determine the agreement of on-combine grain moisture measurement with laboratory measurement methods, and to assess the suitability of on-combine grain moisture measurement. The appropriateness of on-combine measurement of grain moisture content for the management of harvesting and postharvest operations and capacity planning by maintaining a defined acceptable level of disagreement was also investigated. On-combine moisture measurement (OMC) was compared with two dry-oven methods and two capacitive moisture sensors used in laboratories, in each case for unground and ground grain. Field trials with on-combine moisture measurements and manual sampling were carried out on two farms in Germany in 2014. A total area of 514 ha with 201 manual samples was used for the investigations. The assessment of on-combine moisture measurement indicated that the on-combine approach is suitable for quantifying the variability of grain moisture content. The deviation between indirect laboratory methods and on-combine moisture meters was sufficient to determine the allowable total error that agreed with the defined relative error of two percentage points moisture content. In combination with fuzzy classification of grain moisture measurements, the on-combine moisture meters are suitable for process control and capacity planning for grain harvest and preservation.

Irrigation induces processes that may either decrease or increase greenhouse gas emissions from cropping systems. To estimate the net effect of irrigation on the greenhouse gas emissions, it is necessary to consider changes in the crop yields, the content of soil organic carbon and nitrous oxide emissions, as well as in emissions from the use and production of machinery and auxiliary materials. In this study the net greenhouse gas emissions of a cropping system on a sandy soil in northeast Germany were calculated based on a long-term field experiment coupled with two-year N2O flux measurements on selected plots. The cropping system comprised a rotation of potato, winter wheat, winter oil seed rape, winter rye and cocksfoot each under three nitrogen (N) fertilization intensities with and without irrigation. Total greenhouse gas emissions ranged from 452 to 3503 kg CO2-eq ha−1 and 0.09 to 1.81 kg CO2-eq kg−1 yield. Application of an adequate amount of N fertilizer led to a decrease in greenhouse gas emissions compared to zero N fertilization whereas excessive N fertilization did not result in a further decrease. Under N fertilization there were no significant differences between irrigation and non-irrigation. Increases in greenhouse gas emissions from the operation, production and maintenance of irrigation equipment were mainly offset by increases in crop yield and soil organic carbon contents. Thus, on a sandy soil under climatic conditions of north-east Germany it is possible to produce higher yields under irrigation without an increase in the yield-related greenhouse gas emissions.

The expected increase in broiler meat consumption in Brazil in future will lead to further increase in water use. The objective of this study was to quantify water productivity of four Brazilian broiler farms. Water use in the four farming systems was analyzed in terms of feed production, drinking, cleaning, and cooling. One focus was the crop water productivity of the respective corn and soy producing regions in Brazil. After the spatial and temporal boundaries of the farm system and the water flows were defined, the indicator farm water productivity was calculated to assess water use at the farm scale. The 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 farm water productivity and the crop water productivity were calculated using the modeling software AgroHyd Farmmodel. In all fattening systems, water input for feed production accounted for 99.7% of the total water input. In the four systems, farm water productivity accounted for 0.29–0.33 kg carcass weight per m3 water input, 2.60–2.88 MJ food energy per m3 water input, and 0.15–0.17 R$ per m3 water input. The results showed that the highest water demand was for feed production. Improvements in nutritional management will increase the water efficiency of broiler farms.

In this study modeled full scale application of thermobarical hydrolysis of less degradable feedstock for biomethanation was assessed in terms of energy balance, greenhouse gas emissions, and economy. Data were provided whether the substitution of maize silage as feedstock for biogas production by pretreated cattle wastes is beneficial in full-scale application or not.A model device for thermobarical treatment has been suggested for and theoretically integrated in a biogas plant. The assessment considered the replacement of maize silage as feedstock with liquid and/or solid cattle waste (feces, litter, and feed residues from animal husbandry of high-performance dairy cattle, dry cows, and heifers). The integration of thermobarical pretreatment is beneficial for raw material with high contents of organic dry matter and ligno-cellulose: Solid cattle waste revealed very short payback times, e.g. 9months for energy, 3months for greenhouse gases, and 3years 3months for economic amortization, whereas, in contrast, liquid cattle waste did not perform positive replacement effects in this analysis.

In the light of a dire need to reduce greenhouse gas emissions (GHG) from food value chains, this paper analyses GHG emissions from wine production based on primary data from 5 wineries, one wine cellar and 9 grape producers in Germany and explores main emission sources based on their contributions to variance. Considering system boundaries from cradle to gate we found a 90% confidence interval for results between 0.753 and 1.069 kg CO2e per bottle of wine. Main contributors to variance were bottle weight (31%), electricity usage (18%), heat (11%), yield (−9%), and diesel use in vineyards (9%). Looking at production process phases, 19% of emissions resulted from the production of wine grapes, while 81% were attributable to the winery phase, mainly to the packaging materials (57%). Exploring the mitigation potential of a reduction in bottle weight, reuse of glass bottles, increase in packaging volume and renewable energies, we found that the reuse of glass bottles deserves close attention from wine producers, consumers, and policy makers who strive for an effective decarbonization of the wine value chain. The mitigation potential of the reuse of an average bottle exceeds the mitigation potential from a reduction in bottle weight by more than threefold. A combination of the replacement of grid electricity by renewable energies, bottle weight reduction and reuse can curb GHG emissions per bottle of wine by 47%.

Grain harvesting is one of the most weather-dependent processes in agriculture. Grain moisture contents decide on machinery use and costs and determine the necessary grain harvesting and preservation capacities of farms. The objective of this work is to investigate whether and how recent climate changes in the German state of Brandenburg affect the available field time and the required combine harvester capacity. Weather data, the beginning of harvesting, available hours with defined grain moisture contents and total required harvesting capacity are analyzed for the years 1961–2013 for winter wheat, winter rye, winter barley and spring barley. The trends found differ for the four cereal crops. Compared with 53 years ago, today harvesting starts significantly earlier for two cereal crops (−16 days for spring barley and −11 days for winter wheat). The available harvesting hours show a clear and highly significant increase for winter wheat (up to +9%), a distinct and highly significant decrease for winter barley (up to −20%), as well as a slight and significant decrease for winter rye (up to −3%). Inter-annual variability decreases for winter wheat and increases for winter barley. The unfavorable changes for winter barley do not ultimately affect the total required machinery capacity due to the separate harvesting period and relatively small cropping area for winter barley. In contrast, the primarily favorable trends for winter wheat lead to an increase in the total required combine harvester capacity, since the earlier harvesting period overlaps with the rye harvesting period.

The working group "Adaptation to Climate Change" at the Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB) is introduced. This group calculates the water footprint for agricultural processes and farms, distinguished into green water footprint, blue water footprint, and dilution water footprint. The green and blue water demand of a dairy farm plays a pivotal role in the regional water balance. Considering already existing and forthcoming climate change effects there is a need to determine the water cycle in the field and in housing for process chain optimisation for the adaptation to an expected increasing water scarcity. Resulting investments to boost water productivity and to improve water use efficiency in milk production are two pathways to adapt to climate change effects. In this paper the calculation of blue water demand for dairy farming in Brandenburg (Germany) is presented. The water used for feeding, milk processing, and servicing of cows over the time period of ten years was assessed in our study. The preliminary results of the calculation of the direct blue water footprint shows a decreasing water demand in the dairy production from the year 1999 with 5.98×109 L/yr to a water demand of 5.00×109 L/yr in the year 2008 in Brandenburg because of decreasing animal numbers and an improved average milk yield per cow. Improved feeding practices and shifted breeding to greater-volume producing Holstein-Friesian cow allow the production of milk in a more water sustainable way. The mean blue water consumption for the production of 1 kg milk in the time period between 1999 to 2008 was 3.94±0.29 L. The main part of the consumed water seems to stem from indirect used green water for the production of feed for the cows.

With 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.

Livestock production is the main user of water resources in agricultural production. The objective of this study is to quantify the effects of dairy management strategies such as feeding strategies, milk yield and replacement rate on the water productivity of milk. The study is based on site conditions of North-East Germany. The water input is considered as the sum of crop transpiration from precipitation, the total irrigation water and the drinking water of the animals. Four feeding strategies, based on the maximization of grass silage, maize silage, pasture and concentrate, were analyzed. The milk yield varied between 4000 and 12,000 kg fat corrected milk (FCM) cow−1 year−1 in steps of 2000 kg. Feed water productivity on a dry mass (DM) base varied widely between 1.5 kg(DM) m−3 of water input for grass silage and 2.6 kg(DM) m−3 for maize silage, 0.8–1.8 kg(DM) m−3 for grain and 0.4 kg(DM) m−3 for soybeans from Brazil. The water productivity of milk increased with an increasing milk yield. The lowest water productivity was calculated at 4000 kg(FCM) with 1.1 kg(FCM) m−3 water input. At a milk yield of 8000 kg(FCM) the water productivity was 1.5 kg(FCM) m−3 and at 10,000 and 12,000 kg(FCM) it was 1.6 kg(FCM) m−3. The most beneficial conditions related to water productivity in dairy farming exemplarily for site conditions of North-East Germany are found to be with a milk yield about 10,000 kg(FCM) and a grass silage and maize silage based feeding.

The aim of this study was to investigate the effect of supplemental irrigation on the amount of N2O emissions on a sandy soil in north-east Germany. N2O flux measurements were carried out over two vegetation periods from the emergence of plants to harvest. The level of N2O emissions was low, which is typical for sandy soils in north-east Germany. In both periods, irrigation had no increasing effect on N2O emissions. Relevant factors were the soil temperature and the soil water-filled pore space (WFPS), which were mainly influenced by weather conditions. This may indicate that nitrification was the main source of N2O emissions. In conclusion, this study has confirmed that sandy soils under weather conditions of north-east Germany generally have a very low potential for N2O emissions.

In this article, a drip-fertigation system was compared to a control without irrigation concerning the amount of nitrous oxide (N2O) emissions under the climatic conditions of north-east Germany. The investigation was carried out at a field research station in the federal state of Brandenburg. The mean N2O emissions under drip-fertigation were significantly higher than under non-irrigation. The higher N2O emissions under drip-fertigation can be explained by a constantly higher water-filled pore space (WFPS). These higher values in WFPS were caused by the necessary nutrient supply in combination with additional water application in periods with frequent rainfall.

Biogas production from grassland biomass harvested during landscape management may help to maintain species-rich grassland biotopes, but extensive management and late harvests often result in low-quality biomass. Biogas production from the vegetation of Alopecuretum pratensis, Molinietum caeruleae and Caricetum gracilis, three typical grassland biotopes in north German nature reserves, was investigated in relation to harvest date. In addition, the A. pratensis vegetation was investigated for ensiling and the application of bacterial silage additives. Results indicate that biogas production might be a reasonable utilization pathway for grassland biomass from landscape management if the first cut occurs up to late summer. Methane yields of grassland biomass decreased substantially with later harvest, from up to 309 lN kg−1 organic dry matter (ODM) in May to below 60 lN kg−1 ODM in February, in correlation with increasing crude fibre contents. Caricetum gracilis vegetation was the least suitable feedstock for biogas production. It showed a rapid decline in methane yields with later harvest and 25% lower methane yields compared with other types of grassland vegetation. Application of silage additives is recommended for adequate preservation of grassland biomass from landscape management by ensiling. Addition of homofermentative lactic acid bacteria improved acidification during ensiling if sufficient fermentable sugar was available. The use of inoculant and molasses enhanced methane yields by 3–55%. Additional carbohydrate source is necessary to ensure proper ensilage when grasses are harvested after late autumn.

This study investigates the variance of the overall greenhouse gas mitigation potential of a complete second generation stationary bio-electricity production system, generated by poplar wood chips ( Populus spec. ) in Germany, using Monte Carlo simulations. We computed the GHG emissions as E B = (−0.034 ± 0.021) kg CO 2e MJ −1 (mean ± SD) and the mitigation factor as MF B = (0.274 ± 0.021) kg CO 2e MJ −1 following a life cycle assessment-based approach. Additionally, avoided nitrous oxide (N 2 O) emissions due to land use change were considered in the assessment. The most important factor for the overall mitigation variability was the uncertainty of the organic carbon changes in the soil, followed by the variability of yields. The uncertainty of (i) direct N 2 O emissions from the poplar site or (ii) the reference rye site as well as (iii) the uncertainty of heat recovery percentage was of minor importance. Uncertainties in the global warming potentials of nitrous oxide and methane and in the transport distance were found to be irrelevant. The uncertainty of the GHG mitigation which was associated with this specific electricity generation by poplar wood chips gasification was significantly lower compared to the variability of another common bio-electricity system (biogas). Uncertainty implications seem to be system-specific and therefore should be analysed separately for each bioenergy pathway under consideration.

Purpose: Life cycle assessment (LCA) studies of food products, such as dairy, require many input parameters that are affected by variability and uncertainty. Moreover, correlations may be present between input parameters, e.g. between feed intake and milk yield. The purpose of this study was to identify which input parameters are essential to assess the greenhouse gas (GHG) emissions of milk production, while accounting for correlations between input parameters, and using a systematic approach. Methods: Three diets corresponding to three grazing systems (zero-, restricted and unrestricted grazing) were selected, which were defined to aim for a milk yield of 10,000 kg energy corrected milk (ECM) cow−1 year−1. First, a local sensitivity analysis was used to identify which parameters influence GHG emissions most. Second, a global sensitivity analysis was used to identify which parameters are most important to the output variance. The global analysis included correlations between feed intake and milk yield and between N fertilizer rates and crop yields. The local and global sensitivity analyses were combined to determine which parameters are essential. Finally, we analysed the effect of changing the most important correlation coefficient (between feed intake and milk yield) on the output variance and global sensitivity analysis. Results and discussion: The total GHG emissions for 1 kg ECM ranged from 1.08 to 1.12 kg CO2 e, depending on the grazing system. The local sensitivity analysis identified milk yield, feed intake, and the CH4 emission factor of enteric fermentation of the cows as most influential parameters in the LCA model. The global sensitivity analysis identified the CH4 emission factor of enteric fermentation, milk yield, feed intake and the direct N2O emission factor of crop cultivation as most important parameters. For both grazing systems, N2O emission factor for grazing also turned out to be important. In addition, the correlation coefficient between feed intake and milk yield turned out to be important. The systematic approach resulted in more parameters than previously found. Conclusions: By combining a local and a global sensitivity analysis, parameters were determined which are essential to assess GHG emissions of milk production. These parameters are the CH4 emission factor of enteric fermentation, milk yield, feed intake, the direct N2O emission factor of crop cultivation and the N2O emission factor for grazing. Future research should focus on reducing uncertainty and improving data quality of these essential parameters.

International audience; Irrigation has a critical role for crop production worldwide. In particular, irrigation is a major issue due to the growing food demand and climate change. Irrigation affects yields and the emission of greenhouse gases such as CO2 and N2O by soils. Here, we review the effect of irrigation on soil organic carbon and N2O emissions. We analysed 22 investigations in various regions of the world. Interactions between irrigation, soil and management factors are described. The main points are: (1) The influence of irrigation is strongly dependent on climate and initial soil organic carbon content. For instance, irrigation of cultivated desert soils led to an average increase of 90 % to over 500 % of soil organic carbon. (2) Irrigation of semiarid regions increases soil organic carbon by 11 % to 35 %. (3) No consistent effects of irrigation were observed in humid regions. In many cases, N2O emissions increase after precipitation or irrigation. (4) Comparison of N2O emissions from irrigated and non-irrigated fields shows that availability of reactive nitrogen compounds controls increased N2O emissions under irrigation, in most cases. Here, increases of about 50 % to 140 % in N2O emissions were reported.

Carbon (C) is a central element in organic compounds and is an indispensable resource for life. It is also an essential production factor in bio-based economies, where biomass serves many purposes, including energy generation and material production. Biomass conversion is a common case of transformation between different carbon-containing compounds. At each transformation step, C might be lost. To optimize the C use, the C flows from raw materials to end products must be understood. The estimation of how much of the initial C in the feedstock remains in consumable products and delivers services provides an indication of the C use efficiency. We define this concept as Carbon Utilization Degree (CUDe) and apply it to two biomass uses: biogas production and hemp insulation. CUDe increases when conversion processes are optimized, i.e., residues are harnessed and/or losses are minimized. We propose CUDe as a complementary approach for policy design to assess C as an asset for bio-based production. This may lead to a paradigm shift to see C as a resource that requires sustainable exploitation. It could complement the existing methods that focus solely on the climate impact of carbon.

Fens are organic sites that require drainage for agricultural use. Lowering the groundwater level leads to trade-offs between economic benefits and environmental impacts (i.e., CO2 and nutrient emissions). To identify management options that are both environmentally and economically sustainable, a propaedeutic systematic analysis of the costs, income and profit of different land use and management systems on fenlands is necessary. This study provides an overview of the profitability, labor demand and comparative advantages of feasible management systems on German fenlands. Twenty management practices in four land use systems are analyzed. The results indicate that most management systems are profitable only with subsidies and payments for ecosystem services. In addition to sales revenue, these payments are indispensable to promote peat-saving agricultural practices on fenlands. Regarding the labor aspect, intensive management systems caused an increase in working hours per hectare, which may positively affect employment in rural areas. The calculations obtained in this study can be used as a basis for estimations of greenhouse gas (GHG) mitigation costs when management systems are associated with GHG emission values.

Water is used in dairy farming for producing feed, watering the animals, and cleaning and disinfecting barns and equipment. The objective of this study was to investigate the drinking and cleaning water use in a dairy cow barn. The water use was measured on a well-managed commercial dairy farm in North-East Germany. Thirty-eight water meters were installed in a barn with 176 cows and two milking systems (an automatic milking system and a herringbone parlour). Their counts were logged hourly over 806 days. On average, the cows in the automatic milking system used 91.1 (SD 14.3) L drinking water per cow per day, while those in the herringbone parlour used 54.4 (SD 5.3) L per cow per day. The cows drink most of the water during the hours of (natural and artificial) light in the barn. Previously published regression functions of drinking water intake of the cows were reviewed and a new regression function based on the ambient temperature and the milk yield was developed (drinking water intake (L per cow per day) = −27.937 + 0.49 × mean temperature + 3.15 × milk yield (R2 = 0.67)). The cleaning water demand had a mean of 28.6 (SD 14.8) L per cow per day in the automatic milking system, and a mean of 33.8 (SD 14.1) L per cow per day in the herringbone parlour. These findings show that the total technical water use in the barn makes only a minor contribution to water use in dairy farming compared with the water use for feed production.

Water is used in dairy farming for producing feed, watering the animals, and cleaning and disinfecting barns and equipment. The objective of this study was to investigate the drinking and cleaning water use in a dairy cow barn. The water use was measured on a well-managed commercial dairy farm in North-East Germany. Thirty-eight water meters were installed in a barn with 176 cows and two milking systems (an automatic milking system and a herringbone parlour). Their counts were logged hourly over 806 days. On average, the cows in the automatic milking system used 91.1 (SD 14.3) L drinking water per cow per day, while those in the herringbone parlour used 54.4 (SD 5.3) L per cow per day. The cows drink most of the water during the hours of (natural and artificial) light in the barn. Previously published regression functions of drinking water intake of the cows were reviewed and a new regression function based on the ambient temperature and the milk yield was developed (drinking water intake (L per cow per day) = −27.937 + 0.49 × mean temperature + 3.15 × milk yield (R2 = 0.67)). The cleaning water demand had a mean of 28.6 (SD 14.8) L per cow per day in the automatic milking system, and a mean of 33.8 (SD 14.1) L per cow per day in the herringbone parlour. These findings show that the total technical water use in the barn makes only a minor contribution to water use in dairy farming compared with the water use for feed production.

Bioresources are used in different production systems as materials as well as energy carriers. The same is true for fossil fuel resources. This study explored whether preferential resource usages exist, using a building insulation system as an example, with regard to the following sustainability criteria: climate impact, land, and fossil fuel demand. We considered the complete life cycle in a life cycle assessment-based approach. The criteria were compared for two strategies: one used natural fibers as material and generated production energies from fossil fuels; the other generated production energies from bioenergy carriers and transformed fossil resources into the insulation material. Both strategies finally yielded the same insulation effect. Hence, the energy demand for heating the building was ignored. None of the strategies operated best in all three criteria: While cropland demand was lower in the bioenergy than in the biomaterial system, its fossil fuel demand was higher. Net contribution to climate change was in the same range for both strategies if we considered no indirect changes in land use. Provided that effective recycling concepts for fossil-derived insulations are in place, using bioresources for energy generation was identified as a promising way to mitigate climate change along with efficient resource use.

This paper analyses the comparative advantage of using silage maize or grass as feedstock for anaerobic digestion to biogas from a greenhouse gas (GHG) mitigation point of view, taking into account site-specific yield potentials, management options, and land-use change effects. GHG emissions due to the production of biogas were calculated using a life-cycle assessment approach for three different site conditions with specific yield potentials and adjusted management options. While for the use of silage maize, GHG emissions per energy unit were the same for different yield potentials, and the emissions varied substantially for different grassland systems. Without land-use change effects, silage maize-based biogas had lower GHG emissions per energy unit compared to grass-based biogas. Taking land-use change into account, results in a comparative advantage of biogas production from grass-based feedstock produced on arable land compared to silage maize-based feedstock. However, under current frame conditions, it is quite unrealistic that grass production systems would be established on arable land at larger scale.

Irrigation water demand (IWD) is increasing worldwide, including in regions such as Germany that are characterized with low precipitation levels, yet grow water-demanding crops such as sugar beets, potatoes, and vegetables. This study aimed to calculate and analyze the spatial and temporal changes in the IWD of four crops-spring barley, oat, winter wheat, and potato-between 1902 and 2010 in Germany by using the modeling software AgroHyd Farmmodel. Climatic conditions in Germany continued to change over the investigation period, with an increase in temperature of 0.01K/yr and an increase in precipitation of 1mm/yr. Nevertheless, no significant increasing or decreasing trend in IWD was noted in the analysis. The IWD for the investigated crops in the area of the current "Federal Republic of Germany" over the 109years was 112mm/yr, varying between 100 and 127mm/yr. Changes in cropping pattern and cultivated area over the last century caused large differences in the IWD calculated for each administrative district. The mean annual IWD of over the study period (which was divided into 4 parts) varied between 13,455Mm(3)/yr in the earliest period (1902-1919) and 4717Mm(3)/yr in the latest period (1990-2010). Policy and management measures to adapt to climate change are currently being debated in Germany. The presented results suggest that the effects of the choice of crops (in this case, changes in cropping pattern in the German nation states) had a stronger influence on regional water resources than those of climate variability. Thus, the influence of climate change on water resources is relativized which brings an important input into the debate.

The decreasing availability of water caused by depletion and climate change combined with a growing world population requires the productive use of water now and in the future. The young researcher group "AgroHyd" at the Leibniz-Institute for Agricultural Engineering Potsdam-Bornim (ATB) is currently modeling the water demand for agricultural processes at the farm scale and developing indicators to link the hydrological and agricultural perspectives. The aim of the group is to increase productivity in agriculture by raising water productivity in plant production and livestock farming. The effects of various agronomic measures, individual and in combination, on water productivity are assessed using several indicators. Scenarios of agricultural measures, climate and diets are used to test to what extent the water demand for food production will increase due to growing global change in different regions of the world.

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 , 1.03 kg dry mass per , 5.96 GJ , and 0.25 € . 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.

Shortening chopping length at harvest of biogas crops is a basic method of mechanical pretreatment that potentially affects subsequent conservation and biogas production processes. The objective of this study was to assess the influence of a wider range of particle size distributions achieved by laboratory chopping and of practice-oriented short and very short chopping lengths induced by forage harvesters, respectively, on ensiling parameters and methane formation. Shortening the cutting length enhanced lactic acid fermentation during ensiling and increased methane yield, although the effects of ensilage products on methane production partly overlaid the direct positive influence due to reduced particle size. A maximum increase in methane yield of 11 % to 13 % was obtained in the range of median particle lengths of 33 to 6 mm when taking storage losses into account. Thus, very short chopping lengths are beneficial for conservation and methane formation, yet full assessment necessitates further consideration of additional expenditures at harvest.

Reducing chopping length for biogas crop harvesting is a pretreatment method to support the processes of ensiling and methane formation, yet it also increases expenditures at harvest. To assess environmental performance and economic viability, the effects of reducing chopping lengths from common to very short settings on energy balance, greenhouse gas emissions and profitability were investigated. Assessment was based on data gained by monitoring harvesting and ensiling process chains in practice. Balancing results showed low overall effects of chopping length reduction on net energy yield and net greenhouse gas emissions. Shorter chopping length settings reduced net greenhouse gas emissions slightly while net energy yield and profit only increased significantly in 30 to 40 % of the farm-scale harvests investigated. Conditions promoting intensified chopping include the use of high-capacity harvesters, chopping of lignin-rich feedstocks, high subsidies for generated electricity and the utilisation of waste heat. Owing to numerous influencing factors, profitability cannot be guaranteed and so chopping lengths below 7 to 8 mm are not recommended.

Increased methane yields and enhanced ensilability are reasons in favour of very short cutting lengths when chopping crops for biogas utilisation, though this also leads to higher expenditure at harvest. The objective of this study was to evaluate the effects of very short chopping lengths in maize harvesting on capacities, labour time requirements and process costs of the harvest and ensiling chain. Based on data gathered in field experiments, a model calculation that allowed linkage of harvest and transport processes was applied to assess capacities and machinery performance. Results show a decrease in overall area capacities of harvest and transportation units by 4–24% at a nominal chopping length of 4–6 mm compared with common chopping lengths of 8–10 mm. Harvesting costs increased by 4–21%. The effect of lowering machinery chain performance was diminished with more powerful forage harvesters, smaller field sizes, and larger transport distances. Hence, considerable additional expenditures are to be assumed with shortening of chopping length. However, effects depend on particular field and machinery conditions. There is further need to take the additional benefit for storage and methane production into account before recommendations for optimal length of cut can be provided.

This study presents a cradle-to-gate assessment of the energy balances and greenhouse gas (GHG) emissions of Indonesian palm oil biodiesel production, including the stages of land-use change (LUC), agricultural phase, transportation, milling, biodiesel processing, and comparing the results from different farming systems, including company plantations and smallholder plantations (either out growers or independent growers) in different locations in Kalimantan and Sumatra of Indonesia. The findings demonstrate that there are considerable differences between the farming systems and the locations in net energy yields (43.6–49.2 GJ t−1 biodiesel yr−1) as well as GHG emissions (1969.6–5626.4 kg CO2eq t−1 biodiesel yr−1). The output to input ratios are positive in all cases. The largest GHG emissions result from LUC effects, followed by the transesterification, fertilizer production, agricultural production processes, milling, and transportation. Ecosystem carbon payback times range from 11 to 42 years.

The authors wish to make the following corrections to this paper [1]:(1) In the manuscript, the following text above Figure2should be replaced:“[ . . . ] CUDe of 63.4% (CUDe = 2% + 32.4% + 29.0%; Boundary II in Figure2).”with“[ . . . ] CUDe of 63.3% (CUDe = 2% + 32.4% + 28.9%; Boundary II in Figure1).”(2) Figures1and2should be replaced

To better understand the complex interactions between irrigation and nitrogen fertilizer application on soil organic carbon content, the results from long-term field experiments over a period of 40 years were analysed. The combined effect of irrigation and nitrogen fertilizer rates on crop yields, carbon input by above ground harvest residues and soil organic carbon content has been investigated at a site on a sandy soil in northeast Germany. Combined with nitrogen fertilizer application, irrigation has frequently had a significantly positive effect on crop yield and carbon inputs from above ground harvest residues. However, enhanced carbon inputs to the soil under irrigation did not lead to significantly greater soil organic carbon contents. As the combination of irrigation and nitrogen also improved microbial decomposition by changing of above ground harvest residues C/N ratio and soil moisture, the effect of an additional input of carbon from above ground harvest residues was nullified.

The 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.

Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop production. The surplus area could be used for energy production without affecting the land use necessary for food and feed production. We built a model to investigate the effect of changing nitrogen (N) fertilizer rates on cropping area required for a given amount of crops. We found that an increase in nitrogen fertilizer supply is only justified if GHG mitigation with additional land is higher than 9–15 t carbon dioxide equivalents per hectare (CO2-eq../ha). The mitigation potential of bioenergy production from energy crops is most often not in this range. Hence, from a GHG abatement point of view land should rather be used to produce crops at moderate fertilizer rate than to produce energy crops. This may change if farmers are forced to reduce their N input due to taxes or governmental regulations as it is the case in Denmark. However, with a fertilizer rate 10 % below the economical optimum a reduction of N input is still more effective than the production of bioenergy unless mitigation effect of the bioenergy production exceeds 7 t carbon dioxide (CO2)-eq../ha. An intensification of land use in terms of N supply to provide more land for bioenergy production can only in exceptional cases be justified to mitigate GHG emissions with bioenergy under current frame conditions in Germany and Denmark. Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop production. The surplus area could be used for energy production without affecting the land use necessary for food and feed production. We built a model to investigate the effect of changing nitrogen (N) fertilizer rates on cropping area required for a given amount of crops. We found that an increase in nitrogen fertilizer supply is only justified if GHG mitigation with additional land is higher than 9–15 t carbon dioxide equivalents per hectare (CO2-eq../ha). The mitigation potential of bioenergy production from energy crops is most often not in this range. Hence, from a GHG abatement point of view land should rather be used to produce crops at moderate fertilizer rate than to produce energy crops. This may change if farmers are forced to reduce their N input due to taxes or governmental regulations as it is the case in Denmark. However, with a fertilizer rate 10 % below the economical optimum a reduction of N input is still more effective than the production of bioenergy unless mitigation effect of the bioenergy production exceeds 7 t carbon dioxide (CO2)-eq../ha. An intensification of land use in terms of N supply to provide more land for bioenergy production can only in exceptional cases be justified to mitigate GHG emissions with bioenergy under current frame conditions in Germany and Denmark.