• Authors:
    • Tischew, S.
    • Reisinger, E.
    • Luick, R.
    • Jedicke, E.
    • Metzner, J.
  • Source: NATURSCHUTZ UND LANDSCHAFTSPLANUNG
  • Volume: 42
  • Issue: 12
  • Year: 2010
  • Summary: Extensive Grazing and Requirements for the new Agricultural Policy - Promotion of biological diversity, climate protection, water balance and landscape aestheticsThe near-natural pasturing of our cultural landscape stands for a modern, multi-functional agriculture. Many farms with grazing animals have an important share in effectively implementing the European challenges to protect biological diversity, climate and water. The subsequent paper - supported by numerous associations - makes proposals for a better establishment of extensive grazing in the funding guidelines of the Common Agricultural Policy (CAP) of the EU after 2013. Existing instruments are to be advanced in the following areas:On extensively grazed grasslands it should in future be possible to generally activate payment claims of the 1(st) column, and to combine them with aid programmes of the 2(nd) column. In order to reduce the risks of reclaims for the applicants the sites are to be identified by a specific code with an "integrated administration and control system", and the implementation of the measures is to be controlled according to nature conservation criteria.In the context of the 2(nd) column the study recommends the expansion of agri-environmental measures - including better co-financing by the EU, additional incentives and contract periods of up to 20 years.Additionally landscape management programmes have to be established on the basis of the Regulation of the EAFRD (Art. 57) - including invested-related measures which are not covered by agri-environmental schemes.The comprehensive counselling of the farms aims to promote a better integration of extensive grazing, ensuring the optimal combination of measures of the 1st and 2nd column.The study recommends the following measures which are particularly eligible: (a) extensive all-year continuous grazing with cattle and horses, (b) conversion of arable fields into extensively grazed grasslands in flood areas and on fen soils, and (c) biotope management with sheep and goats.
  • Authors:
    • Schindler, U.
    • Muller, L.
  • Source: Proceedings of the 10th International Agricultural Engineering Conference
  • Year: 2009
  • Summary: Land management practice is a decisive factor for the quantities of seepage flow and solute leaching, which constitute two fundamental aspects of land use characterised by potentially conflictive ecologic implications. Efficient water use and intelligent water management are essential for Northeast Germany as a sub-humid region marked by an annual water balance deficit between 80 and 250 mm. Throughout that region, measures are in demand to support groundwater recharge. To meet this claim, knowledge is required about suitable land management systems providing drainage flow sustainable in quantity and quality. Long-term soil hydrological measurements were used to quantify deep drainage and nitrate leaching insitu under undisturbed soil conditions. Deep drainage rates and nitrate losses from arable land managed under various farming regimes (integrated, integrated with irrigation, ecologic and low input) and tillage systems (plough and no till) were quantified in the Pleistocene region of Northeast Germany from 1994 to 2007. Soil water content and tension measurements down to 3 m depth and soil water sampling were used to determine deep drainage dynamics and loss of nitrogen by leaching. As dependent on the management system, the nitrate concentration varied between 40 and 150 mg l -1. In connection with annual deep drainage rates between 100 mm and 200 mm during the study period, the annual nitrogen loss varied between 14 and 41 kg ha -1. Differences in nitrogen loss observed between the farming systems were low, but yields increased and nitrogen losses decreased as a result of irrigation throughout the variants. No-till treatment resulted in reduced nitrate leaching (18 kg ha -1) as compared with the tillage system with plough and tooth cultivator (27 kg ha -1). The suitability of long-term soil hydrological in-situ measurements for quantifying arable management effects on ecological processes - deep drainage dynamics and solute leaching - was confirmed. The trend of decreasing deep drainage was low and not significant. However, due to no significance and quite short investigation period it is not allowed to suggest on climate change effects.
  • Authors:
    • Duijnisveld, W. H. M.
    • Flessa, H.
    • Böttcher, J.
    • von der Heide, C.
    • Well, R.
    • Weymann, D.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 85
  • Issue: 3
  • Year: 2009
  • Summary: Production and accumulation of the major greenhouse gas nitrous oxide (N2O) in surface groundwater might contribute to N2O emissions to the atmosphere. We report on a 15 Ntracer study conducted in the Fuhrberger Feld aquifer in northern Germany. A K15NO3 tracer solution (60 atom%) was applied to the surface groundwater on an 8 m2 measuring plot using 45 injection points in order to stimulate production of 15 N2O by denitrification and to detect its contribution to emissions at the soil surface. Samples from the surface groundwater, from the unsaturated zone and at the soil surface were collected in regular intervals over a 72-days period. Total N2O fluxes at the soil surface were low and in a range between -7.6 and 29.1 lg N2O-N m-2h-1.15 N enrichment of N2O decreased considerably upwards in the profile. In the surface groundwater, we found a 15N enrichment of N2O between 13 and 42 atom%. In contrast, 15N enrichment of N2O in flux chambers at the soil surface was very low, but a detectable 15N enrichment was found at all sampling events. Fluxes of groundwater-derived 15N-N2O were very low and ranged between 0.0002 and 0.0018 kg N2O-N ha-1 year-1, indicating that indirect N2O emissions from the surface groundwater of the Fuhrberger Feld aquifer occurring via upward diffusion are hardly significant. Due to these observations we concluded that N2O dynamics at the soil-atmosphere interface is predominantly governed by topsoil parameters. However, highest 15 N enrichments of N2O throughout the profile were obtained in the course of a rapid drawdown of the groundwater table. We assume that such fluctuations may enhance diffusive N2O fluxes from the surface groundwater to the atmosphere for a short time.
  • Authors:
    • Scialabba, N.
    • Hepperly, P.
    • Fließbach, A.
    • Niggli, U.
  • Year: 2009
  • Authors:
    • Klimek, S.
    • Steinmann, H-H
    • Ulber, L.
    • Isselstein, J.
  • Source: Weed Research
  • Volume: 49
  • Issue: 5
  • Year: 2009
  • Summary: Weed species diversity may benefit from organic farming due to enhanced temporal diversification of crop species in a rotation and omission of herbicide applications. However, in intensively managed conventional systems, little evidence exists as to what extent diversified crop rotations contribute to higher weed species richness. Using an on-farm approach, the effect of crop rotation (organic, conventional diverse (CD) and conventional simple (CS) crop rotations) and weed control (with vs. without) on weed species richness, cover, community composition and crop biomass, was analysed in 24 winter wheat fields. Weed species with beneficial functions for invertebrates and birds were analysed separately. Weed species richness was higher in the organic crop rotation, but did not differ between CD and CS crop rotations. Weed control treatment reduced species richness in both conventional rotations, but not in the organic one. Redundancy analyses revealed that crop rotation intensity accounted for the largest part of the explained variation in weed species composition. Results from the study indicate that the maintenance of weed species richness and conservation of species with important ecological functions requires not only temporal diversification of crop species in the rotation, but also an adjustment of weed control strategies.
  • Authors:
    • [Anonymous]
  • Source: Muhle + Mischfutter
  • Volume: 145
  • Issue: 18
  • Year: 2008
  • Summary: The article describes harvest and yield details of the German cereals season 2008. All federal states of Germany are covered and all cereals including milling, feed, industrial and grain maize, but excluding silage and corn-cob-mix maize. In 2008, the total tonnage increased from 23% to 49 million tonnes. The highest yield increases, compared to the poor year 2007, were reported from the northern states, Mecklenburg-Vorpommern, Niedersachsen, Schleswig-Holstein and Nordrhein-Westfalen. Average winter wheat yields were 8.1 t/ha, winter barley 6.6 t/ha and triticale 6.0 t/ha. Spring barley was 4.9 t/ha and oats only 4.6 t/ha. Because of the large quantities, enough good quality milling wheat will be available. An outlook on the EU cereal harvest, the global and USA harvests in 2008 are given at the end of the paper.
  • Authors:
    • Claupein, W.
    • Lewandowski, I.
    • Boehmel, C.
  • Source: Agricultural Systems
  • Volume: 96
  • Issue: 1/3
  • Year: 2008
  • Summary: Given the political targets, it can be expected that in Europe, energy production from agricultural land will increase and that improved systems for its production are needed. Therefore, a four year field trial was conducted on one site in south-western Germany to compare and evaluate the biomass and energy yield performance of important energy crops. Six energy cropping systems with the potential to produce biomass for first and second-generation biofuels were selected. The systems were short rotation willow coppice, miscanthus, switchgrass, energy maize and two different crop rotation systems including winter oilseed rape, winter wheat and winter triticale. The two crop rotation systems were managed in either conventional tillage or no-till soil cultivation systems. The second test parameter was three different crop-specific nitrogen application levels. The performance of the energy cropping systems was evaluated by measuring the biomass yields and calculating the energy yields, as well as through an energy balance and nitrogen budget. Results show the superiority of the annual energy crop maize in dry matter yield (DMY) and primary net energy yield (PNEY=difference between the primary energy yield (DMY * lower heating value) and the energy consumption) performance with peak values at the highest N-application level of 19.1 t DM ha -1 a -1 and 350 GJ ha -1 a -1, respectively. The highest yielding perennial crop was miscanthus with 18.1 t ha -1 a -1 DMY and a PNEY of 277 GJ ha -1 a -1, followed by willow with 15.2 t ha -1 a -1 and 258 GJ ha -1 a -1, at the highest N-application level. Switchgrass showed the lowest yields of the perennial crops with 14.1 t ha -1 a -1 DMY at the highest N-application level. The yields of the two crop rotation systems did not differ significantly and amounted to 14.6 t ha -1 a -1 DMY of both grain and straw at the highest N-application level. Willow showed the significantly highest energy use efficiency (output (PNEY):input (energy consumption)-ratio) with 99 GJ energy output per GJ fossil energy input at the lowest N-application level (no fertilizer). The two crop rotation systems had the lowest energy use efficiency with 20 GJ GJ -1 for the production of total aboveground biomass. Energy maize gave the best energy yield performance but at a relatively high energy input, whereas willow and miscanthus as perennial energy crops combine high yields with low inputs. Results suggest that no-till systems had no negative impact on biomass and energy yields, but that there was also no positive impact on energy saving.
  • Authors:
    • Paustian, K.
    • Lokupitiya, E.
  • Source: Journal of Environmental Quality
  • Volume: 35
  • Year: 2006
  • Summary: Parties to the United Nations Framework Convention on Climate Change (UNFCCC) are required to submit national greenhouse gas (GHG) inventories, together with information on methods used in estimating their emissions. Currently agricultural activities contribute a significant portion (approximately 20%) of global anthropogenic GHG emissions, and agricultural soils have been identified as one of the main GHG source categories within the agricultural sector. However, compared to many other GHG sources, inventory methods for soils are relatively more complex and have been implemented only to varying degrees among member countries. This review summarizes and evaluates the methods used by Annex 1 countries in estimating CO2 and N2O emissions in agricultural soils. While most countries utilize the Intergovernmental Panel on Climate Change (IPCC) default methodology, several Annex 1 countries are developing more advanced methods that are tailored for specific country circumstances. Based on the latest national inventory reporting, about 56% of the Annex 1 countries use IPCC Tier 1 methods, about 26% use Tier 2 methods, and about 18% do not estimate or report N2O emissions from agricultural soils. More than 65% of the countries do not report CO2 emissions from the cultivation of mineral soils, organic soils, or liming, and only a handful of countries have used country-specific, Tier 3 methods. Tier 3 methods usually involve process-based models and detailed, geographically specific activity data. Such methods can provide more robust, accurate estimates of emissions and removals but require greater diligence in documentation, transparency, and uncertainty assessment to ensure comparability between countries. Availability of detailed, spatially explicit activity data is a major constraint to implementing higher tiered methods in many countries.
  • Authors:
    • Frede, H. G.
    • Keller, T.
    • Huisman, J. A.
    • Breuer, L.
  • Source: Geoderma
  • Volume: 133
  • Issue: 1-2
  • Year: 2006
  • Summary: Land use change can lead to changes in a range of soil properties, including soil carbon (C) and nitrogen (N) content, bulk density and pH. Previous investigations on the effects of land use change have been biased towards the impact of forest clearing and afforestation in tropical environments. Therefore, the aim of this study is to determine the impact of a conversion from cropland to grassland on soil properties in two districts of the Lahn-Dill Highlands, Germany. We determined a land use history for the period 1945-2004 from aerial photographs and field surveys. This land use history was used to build a chronosequence of grassland sites with a different age since the conversion from cropland for both districts. Each chronosequence was sampled to determine bulk density, pH, coarse material fraction, C/N ratio and soil C and N content as a function of grassland age. Results showed that there was no clear dependency of soil properties on grassland age for both districts. It was concluded that observed differences within each district are much more related to differences in soil parent material or slope position, instead of land use. Interestingly, the reduction of the chronosequence analysis to a paired site survey led to an opposite conclusion for the Erda district because all investigated soil properties were significantly different for continuous grassland and cropland. This indicates that care is required when interpreting results from paired site surveys, especially when the equality of initial soil conditions is not (or cannot be) tested.
  • Authors:
    • Amon, B.
    • Weiland, P.
    • Trimborn, M.
    • Clemens, J.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 112
  • Issue: 2-3
  • Year: 2006
  • Summary: Biogas treatment of animal manures is an upcoming technology because it is a way of producing renewable energy (biogas). However, little is known about effects of this management strategy on greenhouse gas (GHG) emissions during fermentation, storage, and field application of the substrates compared to untreated slurries. In this study, we compared cattle slurry and cattle slurry with potato starch as additive during the process of fermentation, during storage and after field application. The addition of potato starch strongly enhanced CH4 production from 4230 l CH4 m-3 to 8625 l CH4 m-3 in the fermenter at a hydraulic retention time (HRT) of 29 days. Extending the HRT to 56 days had only a small effect on the CH4 production.Methane emissions from stored slurry depended on storage temperature and were highest from unfermented slurry followed by the slurry/starch mixture. Gas emissions from untreated and fermented slurry during storage were further analyzed in a pilot-scale experiment with different levels of covering such as straw cover, a wooden lid and no cover. Emissions of greenhouse gases (CH4,N2O, NH3) were in the range of 14.3-17.1 kg CO2 eq. m-3 during winter (100 day storage period) and 40.5-90.5 kg CO2 eq. m-3 during summer (140 day storage period). A straw cover reduced NH3 losses, but not overall GHG emissions, whereas a solid cover reduced CH4 and NH3 emissions. After field application, there were no significant differences between slurry types in GHG emissions (4.15-8.12 kg CO2 eq. m-3a-1). GHG emissions from slurry stores were more important than emissions after field application. Co-digestion of slurry with additives such as starch has a large potential to substitute fossil energy by biogas. On a biogas plant, slurry stores should be covered gas-tight in order to eliminate GHG emissions and collect CH4 for electricity production.