• Bodemkenmerken van het afdekkende pakket in relatie tot de kwetsbaarheid van het grondwater in Nederland. De niet met water verzadigde laag

      Groot Obbink DJ; Breeuwsma A; Wosten JHM (Stichting voor BedemkarteringWageningen, 1985-12-31)
      Abstract not available
    • Climate scenarios for semi-arid and sub-humid regions. A comparison of climate scenarios for the dryland regions, in West Africa from 1990 to 2050

      van den Born GJ; Schaeffer M; Leemans R; NOP (Rijksinstituut voor Volksgezondheid en Milieu RIVMICCDWageningen, 2001-02-23)
      The identification of climate scenarios for dryland areas in Sub-Saharan West Africa is part of a project to assess the impact of climate change on water availability, agriculture and food security in drylands (ICCD-project). The project is financed by Netherlands Research Programme on Global Air Pollution and Climate Change (NRP) and part of theme 'Vulnerability of Natural and Social Systems for Climate'. The report describes the development and description of climate scenarios by using results from both integrated assessement models (IAMs) and global atmospheric circulation models (GCMs) for climate change. The resulting scenarios will be appropriate for Sub-Saharan West Africa. The report describes a common definiton of drylands, their general characteristics and geographical distribution, and gives an introduction to climate change and its potential impacts on ecosystems, agro-systems and society. To improve the understanding of the existing methods, special attention is given to the various approaches commonly used to simulate the impact. The focus of the report is mainly the climate-change scenario development and the application of IAMs and GCMs, especially the use of comprehensive IMAGE scenarios to dynamically calculate transient impacts at global, regional and sub-regional scale. For most indicators the situation in 1990, the projection for 2050 and the absolute change are presented, both in table and map format. The last part of the report summarises the results for a set of climate indicators for Sub-Saharan West Africa.<br>
    • An environmental and economic model to assess the abatement costs of nitrate leaching in dairy farming

      Groeneveld RA; Kruitwagen S; Ierland E van; LBG; LUW (Landbouw Universiteit Wageningenvakgroep StaathuishoudkundeWageningen, 1998-06-30)
      In this analysis of the economic impact of reductions in nitrate leaching on dairy farms in the Netherlands, a non-linear optimisation model was developed to describe the production and purchase of fodder (maize, grass and concentrates) and the resulting nitrate leakage for various grazing systems and groundwater classes. The analysis focused on the central eastern part of the Netherlands, where nitrate leakage is a serious problem. The model minimised economic costs, with constraints for production, feed requirements and mass balances for fodder, as well as for nitrate leaching (the maximum admissible rate is 34 kg N ha exp. -1yr exp. -1). Economic costs were shown to be attributable to the increased costs of fodder and processing of manure when nitrate restrictions are tightened. For some groundwater classes with shallow groundwater the costs shown were negligible. For areas with deep groundwater, it was in some cases difficult - if not impossible - to achieve maximum admissible nitrate leaching. Model results indicated a reduction in the financial balance of NLG 0 to NLG 549 per hectare.
    • Exposure and ecological effects of toxic mixtures at field-relevant concentrations. Model validation and integration of the SSEO programme

      Posthuma L; Vijver MG; LER; SEC (Rijksinstituut voor Volksgezondheid en Milieu RIVMAlterraWageningenRadboud Universiteit NijmegenVrije UniversiteitAmsterdamWageningen University and Research Centre WURIMARES, 2007-12-14)
      Local environmental conditions need be taken into account to assess the impacts of diffuse environmental pollution on ecosystems. This was shown in an evaluation of the scientific results of the Dutch Stimulation Programme System-Oriented Ecotoxicological Research, led by RIVM.<br>Effects of diffuse pollution on the environment were studied at three contaminated areas in the Netherlands: the flood plains of a large lowland river (Waal), a tidal area (Biesbosch) and a peat soil area (near Vinkeveen). Diffuse pollution is present in these areas. Type and magnitudes of effects were determined and analysed.<br>The integrated results analysis showed that effects ranged from absent or low, to clearly visible and large. The magnitude of effects depended on the local composition of the mixture, the local characteristics of the soil, the water or the sediment, and the sensitivity of the local micro-organisms, plants and animals being exposed. The combination of these three characteristics influenced the type and magnitude of impacts.<br>The measurement methods and the modelling analyses used in the research programme appeared to be useful for managing the risks of diffuse site contamination. Application of these methods and analyses is useful for the Dutch situation, given the large areas with diffuse contamination. Sanitation of large, diffusely contaminated areas is not a practicable solution. RIVM recommends the development of a toolbox for ecological risk assessment. Application of such a toolbox will lead to a better assessment of local risks, and the assessment will be based more on ecological approaches. Eventually, this will result in linkage between substance-oriented policies and the management of contaminated sites.<br>
    • Impact of climate change on water availability, agriculture and food security in semi-arid regions, with special focus on West Africa

      Verhagen A; Dietz AJ; Ruben R; NOP (ICCDWageningen, 2001-11-23)
      The research effort started with a geographical inventory of all tropical and sub-tropical drylands to map the diversity in aridity, land degradation, population densities and urbanisation of the world's drylands and to put the drylands of West Africa in perspective. It also guided a choice of in-depth study regions within West Africa. The scenario analysis shows a wide variety of outcomes, but with rather strong suggestions that most of dryland West Africa is expected to become a lot dryer. The consequences of these projections are an increase in high-risk environments for agriculture, including a southward shift of the arid and semi-arid zones. Changes in rainfall distribution could mean an additional stress on agricultural production in these areas. Simulation studies clearly reveal a shift of the onset of the growing season and lower yield levels. To understand farmers' behaviour in West African drylands in preparing ('insuring') for dryer conditions and for agro-climatological droughts, in coping with droughts and adverse production conditions, and in adapting to changed conditions afterwards, we looked at their performance before, during and after drought years in the past identifying several adaptation strategies and policy recommendations. The conclusions don't look very grim, contrary to the much-painted 'picture of doom' for Africa. West Africa's shock experience in the 1970s and 1980s did have the result that it became much better prepared for possible new drought shocks, and that its agricultural production performance in the 1990s (when rainfall became considerably better) improved. The future for the Sahel is not necessarily gloomy. However, system breakdown can occur during droughts. One may fear that in those situations religion will be used as a major catalyst for political support to exclusionist claims (Islam versus Christianity and religious sub-groups versus sub-groups) and may result in massive violence and rapid deterioration of all local livelihood options, resulting in a large death toll and mass migration southward and overseas.
    • Integrated assessment of vulnerability to climate change and adaptation options in the Netherlands

      Ierland EC van; Groot RS de; Kuikman PJ; Martens P; Amelung B; Daan N; Huynen M; Kramer K; Szonyi J; Veraart JA; Verhagen A; Vliet A van; Walsum PEV van; Westein E; NOP (AlterraWageningenInternational Centre for Integrative Studies (ICIS)Maastricht University, 2001-11-23)
      In recent decades, it has become increasingly clear that the global climate is becoming warmer and that regional climates are changing. This report summarizes the results of an integrated assessment of vulnerability to climate change and adaptation options in the Netherlands carried out between July 2000 and July 2001 within the framework of the Dutch National Research Program on Global Air Pollution and Climate Change (NRP-2). The project's main aims were: - to provide an overview of scientific insights, expert judgements and stakeholders' perceptions of current and future impacts (positive and negative) of climate change for several economic sectors, human health, and natural systems in the Netherlands, considering various cross-sectoral interactions, - to develop a set of adaptation options for these sectors through a participatory process with the main stakeholders, - to perform an integrated assessment of cross-sectoral interactions of climate change impacts and adaptation options. Climate change impacts and adaptation options have been investigated for several important economic sectors (including agriculture, forestry, fisheries, industry, energy, transport, insurance and recreation & tourism), human health and natural systems (including soils, water and biodiversity issues).The results of this study are based on literature survey, a dialogue with experts and stakeholders. We are convinced that the report represents the most essential and relevant aspects of the impacts and adaptation options for climate change in the Netherlands, given the scenario setting of this study, the state of the art of current scientific knowledge, and today's expert and stakeholders' perceptions of the issues at stake.
    • The integrated nitrous oxide and methane grassland project

      Leffelaar PA; Langeveld CA; Hofman JE; Segers R; Pol-Dasselaar van den A van; Goudriaan J; Rabbinge R; Oenema O; NOP (Wageningen Agricultural UniversityDepartment of Theoretical Production EcologyWageningen, 2000-03-29)
      The integrated nitrous oxide (N2O) and methane (CH4) grassland project aims to estimate and explain emissions of these greenhouse gases from two ecosystems, namely drained agricultural peat soil under grass at the experimental farm Zegveld and undrained peat in the nature preserve Nieuwkoopse Plassen. Peat soils were chosen because of their expected considerable contribution to the greenhouse gas budget considering the prevailing wet and partial anaerobic conditions. The emission dynamics of these ecosystems are considered representatives of large peat areas because the underlying processes are rather general and driven by variables like organic matter characteristics, water and nutrient conditions and type of vegetation. The research approach comprises measerements and modelling at different integration levels relating to the microbiology of the production and consumption of N2O and CH4 (laboratory studies), their movement through peat soil (rhizolab and field studies), and the resulting fluxes (field studies). Typical emissions from drained soil were 15-40 kg ha-1 y-1 N2O and virtually zero for CH4. The undrained soil in the nature preserve emitted 100-280 kg ha-1 y-1 CH4, and probably little N2O. The process knowledge collected and partly integrated in the models helps to explain these data. For example, the low methane emissions from drained peat can more coherently be understood and extrapolated because (i) upper soil layers are aerobic, thus limiting methane production and stimulating methane oxidation, (ii) absence of aerenchymatous roots of wetland plants that connect deeper anaerobic soil layers where methane is produced to the atmosphere and supply labile carbon, (iii) a low methane production potential in deep layers due to the low decomposability of organic matter, and (iv) long anaerobic periods needed in the topsoil to develop a methane production potential.
    • Long-term changes of chemistry and biota in moorland pools in relation to changes in atmospheric deposition

      Dam H van; Houweling H; Wortelboer FG; Erisman JW; Smeulders SM; LWD; LLO; IBN-DLO; AquaSense TEC (AquaSense TECWageningenDLO-Instituut voor Bosbouw en NatuuronderzoekWageningen, 1996-04-19)
      Major changes in chemistry and biota of three moorland pools have been registered in the period 1979 - 1994 in view of the acidification and eutrophication by atmospheric deposition. The data have been compared with data from the period 1912-1970. By model calculations the changes in these periods were studied with regard to particularly sulphur and nitrogen compounds. Recommendations for future monitoring are made, tailored to the needs of environmental policy.
    • Milieu-indicator 1999: Resultaten van een verkenning naar een indicator voor het gewasbeschermingsmiddelenbeleid

      Brouwer WWM; Marsman H; Luttik R; CSR (Rijksinstituut voor Volksgezondheid en Milieu RIVMPlantenziektenkundige Dienstafdeling FytofarmacieWageningen, 2000-02-01)
      The Ministry of Housing, Spatial Planning and the Environment commissioned the RIVM to assess the environmental effect of the policy measures for sustainable construction, for the period 1995 - 2020. This study asseses the environmental effects of technical measures for the reduction of energy use, water use and the use of materials in existing and new dwellings and utility buildings. Two models have been developed, one for dwellings and one for utility buildings (only for the sectors health, education, offices and retail trade). These models are uses to assess technical measures of the National Sustainable Construction Package for the reduction of energy, water use and the use of materials in existing and new dwellings and buildings can be assessed. Behavioral changes have not been included in the models. In order to calculate the effects the measures with regard to sustainable construction have been equipped with penetration scenarios. These penetration scenarios are explicated in consultation with experts (in the fields of policy and construction). For the dwellings in the Netherlands a reduction of energy use for space heating with approximately 15% is calculated. As a result the CO2-emission related to space heating will also decline. In utility buildings the energy use per m2 gross ground area will decline. As a result of the increase in ground area for most of the sectors in utility buildings the energy use (and the resulting CO2-emission) will be stable. The reduction of water use in dwellings is much larger than in utility buildings. This is a result of the much larger possibilities of water reduction in dwellings as compared to utility buildings. The reduction of material use has also been assessed in the prognosis. In the near future environmental profit will be gained in the recycling of materials for buildings, for instance for shingle, gypsum and PVC. In the reduction of harmful emissions, for instance for volatile organic compounds and heavy metals. In the durable use and the reduction in use of non-renewable elements, for instance wood and tar products.<br>
    • Milieukwaliteit en nutrientenbelasting : Achtergrondrapport milieukwaliteit van de Evaluatie Meststoffenwet 2007

      Klijne A de; Hooijboer AEJ; Bakker DJ; Schoumans OF; Ham A van den; LVM (RIZALelystadAlterraWageningenLandbouw Economisch InstituutDen Haag, 2007-10-29)
      The manure policy has led to a reduction in the surplus amounts of nitrogen and phosphate on farms in the Netherlands occurring up to 2001. Surplus amounts have stabilised since 2001. The quality of the soil has either remained the same or has deteriorated. The quality of groundwater improved up to 2002 and has remained roughly the same since then. The quality of surface water has improved although it is not clear what has caused this improvement to occur after 2001. A surplus arises when more nitrogen and phosphate based fertilizers are used than is necessary for crop cultivation. This puts a strain on the environment. The National Institute for Public Health and the Environment (RIVM) has investigated the effects of these surpluses on the quality of the soil, ground and surface water on and in the direct vicinity of farms. The current manure policy still results in surplus levels of phosphate in the soil. This has led to further increases in the phosphate saturation rate on farmland. Currently, more than 56 percent of farmland areas are saturated with phosphate. The European standard for nitrate levels in groundwater on farms is not always achieved. In clay and peat areas, the average nitrate concentration is lower than the European standard. In sandy and loessy soil areas, the average concentration exceeds this standard. The concentrations of nitrogen and phosphate in surface water remain on the decrease, although this decrease is less than it has been in previous years. More than half of the locations (57 percent) in regional waters do meet the standard (maximum permissible risk) for phosphate levels. For nitrogen levels, approximately 34 percent of the locations meet this standard.
    • Opzet voor een leidraad bodembeoordeling bij natuurontwikkeling; raamwerk van een ecotoxicologische risicobeoordeling voor natuurontwikkeling binnen de Ecologische Hoofdstructuur

      Lijzen JPA; ter Meulen GRB; de Vries W; LBG; ECO; SC-DLO; Wageningen (Rijksinstituut voor Volksgezondheid en Milieu RIVMDienst Landbouwkundig Onderzoek-Staring CentrumWageningen, 1997-06-30)
      This Guideline will be useful for limiting, constructing, managing or purchasing agricultural land on behalf of the Netherlands' National Ecological Network. The soils of agricultural areas are often slightly polluted, possibly even so polluted that objectives for development of natural areas can not be achieved. Therefore the Guideline should determine whether a location has enough potential for realizing the intended objectives, considering the soil pollution, and whether construction and management of the area could improve opportunities. This is done by means of an ecotoxicological risk assessment. This is based on 'bioavailable' fractions of the soil contaminants, since land-use changes can lead to changes in soil conditions (pH, redox, organic matter) which can change the bioavailable fractions. The framework of the Guideline consists of the following six modules: 1) actual conditions and basic data, 2) the desired development and corresponding scenarios, 3) prognosis of future soil conditions, 4) prognosis of future available fractions of the contaminants, 5) ecotoxicological risk assessments, and 6) the integration of the modules and other relevant factors, and final assessment.<br>
    • Representation of the seasonal hydrological cycle in climate and weather prediction models in West Europe

      Dolman AJ (eds); NOP (Alterra Research Instituut voor de Grone RuimteWageningen, 2000-05-25)
      This report contains results from the first two years of the project "Representation of the seasonal hydrological cycle in climate and weather prediction models in West Europe", NRP project 951246. Its two main objectives are: 1)To understand the causes of excessive drying over the European continental area in the large scale climate and weather forecast models 2) To improve the representation of the seasonal hydrological cycle in climate and weather prediction models. The report reviews existing studies showing that the land surface can be an important factor in determining weather and climate. A particularly important role plays soil moisture, because it acts as a long term memory to the system. Analysis is based around the national Regional Atmospheric Climate Model (RAMCO). The evaluation of the RAMCO Land Surface Model indicated that the introduction of site specific parameters has a significant effect on simulated water budgets. This study also shows that implementation of all site specific information in RAMCO does not automatically lead to the best performance. Thus, the interaction between different aspects of the LSM stresses the need for careful analysis of future model adjustments, both off-line and coupled to the atmospheric model.
    • Terrestrial carbon sinks and the Kyoto protocol: the scientific issues

      Dolman H; Nabuurs GJ; Kuikman P; Vleeshouwers L; Verhagen J; Kruijt B; Brinkman S; NOP (AlterraWageningen, 2001-06-29)
      Since the publication of the IPCC special report on Land Use, Land Use Change and Forestry, considerable advances in our understanding of the global carbon cycle have occurred. This report attempts to review the terrestrial part of that cycle and assesses the implications for the implementation of then Kyoto protocol. The review assesses the impacts of the effects of continuing carbon uptake of old growth forest, interannual variability of terrestrial uptake. It is speculated that impact on N-deposition on carbon sequestration is small (of order 10%). It is unknown whether agriculture at large is a source or sink. Lack of knowledge of soil organic carbon contributes strongly to this uncertainty. The sustainability of the terrestrial sink also reviewed. It is concluded that eventually all sinks saturate, but that land use management can play a critical role in sustaining the sink strength. The role of feedback of the terrestrial carbon pools on climate change is discussed.
    • Typeringen van bodemecosystemen in Nederland met tien referenties voor biologische bodemkwaliteit

      Rutgers M; Mulder C; Schouten AJ; Bloem J; Bogte JJ; Breure AM; Brussaard L; de Goede RGM; Faber JH; Jagers op Akkerhuis GAJM; Keidel H; Korthals GW; Smeding FW; ten Berg C; van Eekeren N; LER (Rijksinstituut voor Volksgezondheid en Milieu RIVMAlterraWageningenWageningen UniversiteitPraktijkonderzoek Plant en OmgevingWageningenLouis Bolk Instituut, 2007-12-14)
      RIVM and other institutes described ten soil system profiles (the so-called biological soil references) according to the soil quality as inferred from existing empirical evidence of previously investigated sites. This is a pilot study, since no specific protocol has yet been established. These new references aim to be used as benchmarks to implement a more sustainable use of soils. References were derived from a combination of data from land-use (e.g. dairy farms, arable fields and heathlands) and soil type (sand, peat, clay and loess). Our approach covers the soils of about three-quarters of the surface of the Netherlands. Several scientists, with expertise ranging from soil ecology and microbiology up to rural management, selected sites where data was seen by them as representative of good soil quality. For this purpose these scientists used soil monitoring data from the Netherlands Soil Monitoring Network (in Dutch: LMB). The ten references were derived from empirical data. This report also provides the averages and frequency distributions of biological, chemical and physical soil characteristics. The extent to which soil organisms occur has been described as well as their biodiversity.
    • Typeringen van bodemecosystemen- Duurzaam bodemgebruik met referenties voor biologische bodemkwaliteit

      Rutgers M; Mulder C; Schouten AJ; Bogte JJ; Breure AM; Bloem J; Jagers op Akkerhuis GAJM; Faber JH; van Eekeren N; Smeding FW; Keidel H; de Goede RGM; Brussaard L; LER (Rijksinstituut voor Volksgezondheid en Milieu RIVMAlterraWageningenLouis Bolk InstituutDriebergenBedrijfslaboratorium voor grond- en gewasanalyseOosterbeekSectie BodemkwalitieitWageningen Universiteit, 2006-02-24)
      The coming years will see a transformation in the Dutch policy for soil protection, with the focus shifting from soil protection to sustainable use of the soil. Within the framework for sustainable land use, the Dutch Ministry of Housing, Spatial Planning and the Environment (VROM) requested RIVM and other institutes to formulate quality references for a 'healthy' soil. Two references were formulated: one for dairy farming on sandy soil and one for natural grassland on sandy soil. References are represented by numerical values for chemical, physical, biological and other parameters. Data for determining references were derived from the database of the soil biological indicator sub-set of the Dutch Soil Monitoring Network. A step-by-step approach was developed to select key parameters from the indicator sub-set. This approach was based on the so-called soil 'ecosystem services', i.e. soil fertility, resistance and resilience against stress and disturbance, the buffer and reactor capacity of the soil, and biodiversity. 'Soil health' can therefore be assumed to be determined with the key parameters only.