Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2017
Authors
Kris Van Looy Johan Bouma Michael Herbst John Koestel Budiman Minasny Umakant Mishra Carsten Montzka Attila Nemes Yakov A. Pachepsky José Padarian Marcel G. Schaap Brigitta Tóth Anne Verhoef Jan Vanderborght Martine J. van der Ploeg Lutz Weihermüller Steffen Zacharias Yonggen Zhang Harry VereeckenAbstract
Soil, through its various functions, plays a vital role in the Earth’s ecosystems and provides multiple ecosystem services to humanity. Pedotransfer functions (PTFs) are simple to complex knowledge rules that relate available soil information to soil properties and variables that are needed to parameterize soil processes. In this paper, we review the existing PTFs and document the new generation of PTFs developed in the different disciplines of Earth system science. To meet the methodological challenges for a successful application in Earth system modeling, we emphasize that PTF development has to go hand in hand with suitable extrapolation and upscaling techniques such that the PTFs correctly represent the spatial heterogeneity of soils. PTFs should encompass the variability of the estimated soil property or process, in such a way that the estimation of parameters allows for validation and can also confidently provide for extrapolation and upscaling purposes capturing the spatial variation in soils. Most actively pursued recent developments are related to parameterizations of solute transport, heat exchange, soil respiration, and organic carbon content, root density, and vegetation water uptake. Further challenges are to be addressed in parameterization of soil erosivity and land use change impacts at multiple scales. We argue that a comprehensive set of PTFs can be applied throughout a wide range of disciplines of Earth system science, with emphasis on land surface models. Novel sensing techniques provide a true breakthrough for this, yet further improvements are necessary for methods to deal with uncertainty and to validate applications at global scale.
Authors
Anne-Grete Buseth BlankenbergAbstract
No abstract has been registered
Abstract
This work presents the outcomes from two independent studies evaluating the chemical quality of groundwater in agricultural areas irrigated with wastewater from sugar and yeast industries. The evaluation was determined using chemical parameters representing typical contaminants of sugar industry wastewater (SIWW) and yeast industry wastewater (YIWW), and characterising the content of organic matter (BOD5), nutrients (NH4-N, NO3-N, TN and TP) and salts (Cl, SO4, Na and K). The studies reveal that food industry wastewater constitutes a valuable water-nutrient-rich medium that can be reused in agricultural applications as an alternative water resource for irrigation and nutrients for fertilisation. Furthermore, the reuse facilitates the sustainable discharge of wastewater through a soil-aquifer zone to the natural environment. This does not affect chemical quality of groundwater, which was comparable in areas irrigated and non-irrigated with SIWW and YIWW. Although some parameters (NO3-N, NH4-N, SO4, Cl and Na) displayed higher concentrations in groundwater from the fields irrigated with wastewater, these contents were within recommended healthbased guideline limits defined in either the groundwater quality standards or the drinking water quality norms. Only the contents of K revealed an exclusive groundwater impact from wastewater irrigation. This was confirmed in statistical tests employing theWard’s hierarchical clustering method, which exposed excessive amounts of K introduced into groundwater through irrigation with both SIWW and YIWW. However, this parameter is not considered to pose any health risk to humans or the environment, and its content is not restricted by quality guideline values for either groundwater or drinking water.
Abstract
This work focuses on modelling soil water reserves using an Artificial Neural Net-work (ANN). Four model variants were established based on 843 records (verifiedthrough 268 measurements) of soil water content (SWC) measured at full-scale fieldsites located in Southwest Poland. It is revealed that commonly recorded climaticdata (precipitation and temperature) linked with SWC and field water capacity(FWC) are applicable in the ANN modelling. The basic model (utilising the meteoro-logical data) was the most suitable for soil profiles with thicknesses of 0–25 cm,while in profiles with thicknesses of 0–50 cm and 0–100 cm the comprehensiveANN model (linking climatic data, FWC and SWC) was the most appropriate. Fur-thermore, comparative studies of the measured and modelled data indicated theirstatistical convergence, thus providing support for the practical implementation ofthe proposed ANN modelling.
Abstract
No abstract has been registered
Abstract
Several studies focus on the effects of climate variability on female and male gender relations as perceived through various biophysical and socio-economic aspects. More emphasis is given on the impacts of extreme weather events on rural communities of less developed regions. The results are often interpreted in a qualitative manner through policy measures that may reduce gender inequalities. However, the interpretation of the qualitative results to more crisp and measurable outputs is often not attained while the validation of the findings is rarely ensured. The current study suggests a gender-differentiated impact framework based on qualitative and quantitative components for the assessment of climate variability effects on rural communities in South India. Fifteen villages mostly practicing rice farming in Andhra Pradesh and Telangana states were selected as representative drought-prone case studies. The study results advocate that the qualitative outcomes were validated from the quantitative approach but for a few cases which could be attributed to methodological and case-specific differentiations. Policy recommendations are made on common gender trainings in water-resistant crops and livestock activities for the alleviation of drought impact and abatement of gender inequalities. Also, entrepreneurship workshops for women could enhance gender balance and diverse family income from the current sole dependence on farming revenues. Regional climate adaptation programs could be better implemented when the specific features and capacities of local communities are taken into consideration.
Authors
Trond MæhlumAbstract
No abstract has been registered
Abstract
Management of peat soils is regionally important as they cover large land areas and have important but conflicting ecosystems services. A recent management trend for drained peatlands is the control of greenhouse gases (GHG) by changes in agricultural practices, peatland restoration or paludiculture. Due to complex antagonistic controls of moisture, water table management can be difficult to use as a method for controlling GHG emissions. Past studies show that there is no obvious relationship between GHG emission rates and crop type, tillage intensity or fertilization rates. For drained peat soils, the best use options can vary from rewetting with reduced emission to efficient short term use to maximize the profit per amount of greenhouse gas emitted. The GHG accounting should consider the entire life cycle of the peatland and the socio-economic benefits peatlands provide locally. Cultivating energy crops is a viable option especially for wet peat soils with poor drainage, but harvesting remains a challenge due to tractability of wet soils. Paludiculture in lowland floodplains can be a tool to mitigate regional flooding allowing water to be stored on these lands without much harm to crops. This can also increase regional biodiversity providing important habitats for birds and moisture tolerant plant species. However, on many peatlands rewetting is not possible due to their position in the landscape and the associated difficulty to maintain a high stable water table. While the goal of rewetting often is to encourage the return of peat forming plants and the ecosystem services they provide such as carbon sequestration, it is not well known if these plants will grow on peat soils that have been altered by the process of drainage and management. Therefore, it is important to consider peat quality and hydrology when choosing management options. Mapping of sites is recommended as a management tool to guide actions. The environmental status and socio-economic importance of the sites should be assessed both for continued cultivation but also for other ecosystem services such as restoration and hydrological functions (flood control). Farmers need advice, tools and training to find the best after-use option. Biofuels might provide a cost-efficient after use option for some sites. Peat extraction followed by rewetting might provide a sustainable option as rewetting is often easier if the peat is removed, starting the peat accumulation from scratch. Also this provides a way to finance the after-use. As impacts of land use are uncertain, new policies should consider multiple benefits and decisions should be based on scientific evidence and field scale observations. The need to further understand the key processes and long term effects of field scale land use manipulations is evident. The recommended actions for peatlands should be based on local condition and socio-economic needs to outline intermediate and long term plans.
Authors
Johannes DeelstraAbstract
In Norway, and many other countries, subsurface drainage systems are a necessity to practice agriculture. Drainage systems, through control of the groundwater level, have a direct influence on the soil moisture content. To facilitate tillage practices and harvesting depending on soil type, the soil moisture content has to be at 80 – 90% of the field capacity in the top 20 cm of the soil profile. The main objective was to get information about the half time , i.e. the time required to reduce the runoff to 50% of the runoff at the onset of a recession period. The average half time for the small field scale catchments varied from 6 – 16 hours, indicating a fast drawdown of the water Level. The analysis of subsurface drainage is carried out as part of IRIDA, an EU/JPI funded project.
Authors
Anne Gobin Kurt Christian Kersebaum Josef Eitzinger Miroslav Trnka Petr Hlavinka Jozef Takác Joop Kroes Domenico Ventrella Anna Dalla Marta Johannes Deelstra Branislava Lalic Pavol Nejedlik Simone Orlandini Pirjo Peltonen-Sainio Ari Rajala Triin Saue Levent Saylan Ruzica Stricevic Visnja Vucetic Christos ZoumidesAbstract
Crop growth and yield are affected by water use during the season: the green water footprint (WF) accounts for rain water, the blue WF for irrigation and the grey WF for diluting agri-chemicals. We calibrated crop yield for FAO’s water balance model “Aquacrop” at field level. We collected weather, soil and crop inputs for 45 locations for the period 1992–2012. Calibrated model runs were conducted for wheat, barley, grain maize, oilseed rape, potato and sugar beet. The WF of cereals could be up to 20 times larger than the WF of tuber and root crops; the largest share was attributed to the green WF. The green and blue WF compared favourably with global benchmark values (R2 = 0.64–0.80; d = 0.91–0.95). The variability in the WF of arable crops across different regions in Europe is mainly due to variability in crop yield (cv = 45%) and to a lesser extent to variability in crop water use (cv = 21%). The WF variability between countries (cv = 14%) is lower than the variability between seasons (cv = 22%) and between crops (cv = 46%). Though modelled yields increased up to 50% under sprinkler irrigation, the water footprint still increased between 1% and 25%. Confronted with drainage and runoff, the grey WF tended to overestimate the contribution of nitrogen to the surface and groundwater. The results showed that the water footprint provides a measurable indicator that may support European water governance.