Hopp til hovedinnholdet

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.

2023

To document

Abstract

The H2020 OPTAIN project involves both, catchment-, and field-scale modelling of the transport of water and nutrients. The catchment-scale modelling is performed at fourteen case study catchments across Europe using the SWAT+ model. At seven OPTAIN case studies, field-scale modelling is applied using the SWAP model. The aim of the SWAP modelling is to provide data on soil water balance elements using a more detailed (at field-scale) soil hydrological model and to cross-validate this data with the relevant fields in SWAT+. As the official manual from the SWAP model developers is rather detailed and complex, the OPTAIN SWAP modelling protocol focuses on practical issues, without overwhelming the modellers with information unnecessary for their case-studies. It also describes new tools, such as rswap, developed within the OPTAIN project for reference data quality check, model calibration and visualisation of the model results.

To document

Abstract

Soil organic carbon (SOC) is the largest terrestrial carbon pool, but it is still uncertain how it will respond to climate change. Especially the fate of SOC due to concurrent changes in soil temperature and moisture is uncertain. It is generally accepted that microbially driven SOC decomposition will increase with warming, provided that sufficient soil moisture, and hence enough C substrate, is available for microbial decomposition. We use a mechanistic, microbially explicit SOC decomposition model, the Jena Soil Model (JSM), and focus on the depolymerization of litter and microbial residues by microbes. These model processes are sensitive to temperature and soil moisture content and follow reverse Michaelis-Menten kinetics. Microbial decomposition rate V of the substrate [S] is limited by the microbial biomass [B]: V = Vmax * [S] * [B]/(kMB + [B]). The maximum reaction velocity, Vmax, is temperature sensitive and follows an Arrhenius function. Also, a positive correlation between temperature and kMB-values of different enzymes has been empirically shown, with Q10 values ranging from 0.71-2.80 (Allison et al., 2018). Q10 kMB-values for microbial depolymerization of microbial residues would be low compared to those of a (lignified) litter pool. An increase in kMB leads to a lower reaction velocity (V) and V becomes less temperature sensitive at low substrate concentrations. In this work we focus on the following questions: “how do temperature and soil moisture changes affect modelled heterotrophic respiration through the Michaelis-Menten term? Is there a temperature compensation effect on modelled decomposition rate because of the counteracting temperature sensitivities of Vmax and kMB?” We model these interactions under a mean warming experiment (+3.5 °K) as well as three soil moisture experiments: constant soil moisture, a drought, and a wetting scenario.

To document

Abstract

This chapter gathers information about the current legal requirements related to the emission of ammonia from animal housing in 24 out of the 27 EU countries and in 7 non-EU countries. Overall, the chapter shows that most of the included countries have established substantial procedures to limit ammonia emission and practically no procedures to limit greenhouse gas emission. The review can also be seen as an introduction to the substantial initiatives and decisions taken by the EU in relation to ammonia emission from animal housing, and as a notification on the absence of corresponding initiatives and decisions in relation to greenhouse gases. An EU directive on industrial emissions from 2010 and an implementation decision from 2017 are the main general instruments to reduce ammonia emission from animal housing in the EU. These treaties put limits to ammonia emissions from installations with more than 2000 places for fattening pigs, with more than 750 places for sows, and with more than 40,000 places for poultry. As an example, the upper general limit for fattening pigs is 2.6 kg ammonia per animal place per year. This chapter indicates that the important animal producing countries in the EU as well as United Kingdom have implemented the EU requirements and that a few countries including the Flemish part of Belgium, Denmark, the Netherlands, Slovakia, and Spain have introduced even stricter requirements.