Regional variations in diffuse nitrogen losses from agriculture in the Nordic and Baltic regions

International audienceThis paper describes nitrogen losses from, and the characteristics of, 35 selected catchments (12 to 2000 ha) in the Nordic and Baltic countries. Average annual losses of N in 1994?1997 ranged from 5 to 75 kg ha-1, generally highest and characterised by significant within-country and interannual variations, in Norway and the lowest losses were observed in the Baltic countries. An important finding of the study is that the average nutrient losses varied greatly among the studied catchments. The main explanations for this variability were water runoff, fertiliser use (especially the amount of manure), soil type and erosion (including stream bank erosion). However, there were several exceptions, and it was difficult to find general relationships between the individual factors. For example, there was poor correlation between nitrogen losses and surpluses. Therefore, the results suggest that the observed variability in N losses cannot have been due solely to differences in farm management practices, although the studied catchments do include a wide range of nutrient application levels, animal densities and other relevant elements. There is considerable spatial variation in the physical properties (soil, climate, hydrology, and topography) and the agricultural management of the basins, and the interaction between and relative effects of these factors has an important impact on erosion and nutrient losses. In particular, hydrological processes may have a marked effect on N losses measured in the catchment stream water. The results indicate that significant differences in hydrological pathways (e.g. the relationship between fast- and slow-flow processes) lead to major regional differences in N inputs to surface waters and therefore also in the response to changes in field management practices. Agricultural practices such as crop rotation systems, nutrient inputs and soil conservation measures obviously play a significant role in the site-specific effects, although they cannot explain the large regional differences observed in this study. The interactions between agricultural practices and basic catchment characteristics, including hydrological processes, determine the final losses of nitrogen to surface waters, hence it is necessary to understand these interactions to manage diffuse losses of agricultural nutrients efficiently. Keywords: agriculture, catchments, diffuse sources, nitrogen, losses, Baltic, Nordi

Tiltaksanalyse for Morsa (Vansjø-Hobøl-vassdraget) - Sluttrapport

Årsliste 2001Tiltaksanalysen for Morsa (Vansjø-Hobølvassdraget) viser at vassdraget er overbelastet med næringssalter. Den totale fosfortilførselen er beregnet til ca. 19 tonn, hvorav ca. 5 tonn kommer fra naturlig bakgrunnsavrenning, 11 tonn fra jordbruket, 2 tonn fra spredt kloakkavløp (2210 separate avløpsanlegg er registrert i nedbørfeltet) og 1 tonn fra kommunalt kloakkavløp. For å nå miljømålene om at Vansjø-Storefjorden skal egne seg til drikkevann og at vassdraget for øvrig skal egne seg til bading, fritidsfiske og jordvanning må 65% av de menneskeskapte fosfortilførslene fjernes. Kvantifiserte tiltak innen jordbruket (der endret jordarbeiding er det viktigste enkelttiltaket), tiltak innen separate avløp (særlig på direkte utslipp og slamavskillere), samt utbedring av feilkoblinger på kommunale kloakkledninger vil fjerne drøyt 50% av de menneskeskapte fosfortilførslene, mens andre tiltak innen jordbruk og avløpssektoren (særlig mot overløp og lekkasjer) vil kunne gi betydelige tilleggsgevinster, som sannsynliggjør oppnåelse av målet om 65% reduksjon. Overføring av restutslipp fra to kommunale renseanlegg til andre resipienter vil fjerne < 0,5 % av tilførslene og være lite kostnadseffektivt idag. Dersom antall tilknyttede boliger tredobles i framtiden vil tiltaket kunne få en kostnadseffektivitet som er ca. 2 ganger dårligere enn tiltak innen separate avløp. Vassdragsinterne tiltak som utfisking og regulering av vannstanden har potensiale til å gi ytterligere forbedringer, men effekten er vanskelig å kvantifisere. Klimaendringer vil kunne motvirke effekten av de iverksatte tiltakene og potensielt forverre dagens tilstand i vassdraget.Hovedstyret for Morsa-prosjekte

Influence of Lag Effect, Soil Release, And Climate Change on Watershed Anthropogenic Nitrogen Inputs and Riverine Export Dynamics

This study demonstrates the importance of the nitrogen-leaching lag effect, soil nitrogen release, and climate change on anthropogenic N inputs (NANI) and riverine total nitrogen (TN) export dynamics using a 30-yr record for the Yongan River watershed in eastern China. Cross-correlation analysis indicated a 7-yr, 5-yr, and 4-yr lag time in riverine TN export in response to changes in NANI, temperature, and drained agricultural land area, respectively. Enhanced by warmer temperature and improved agricultural drainage, the upper 20 cm of agricultural soils released 270 kg N ha(-1) between 1980 and 2009. Climate change also increased the fractional export of NANI to river. An empirical model (R(2) = 0.96) for annual riverine TN flux incorporating these influencing factors estimated 35%, 41%, and 24% of riverine TN flux originated from the soil N pool, NANI, and background N sources, respectively. The model forecasted an increase of 45%, 25%, and 6% and a decrease of 13% in riverine TN flux from 2010 to 2030 under continued development, climate change, status-quo, and tackling scenarios, respectively. The lag effect, soil N release, and climate change delay riverine TN export reductions with respect to decreases in NANI and should be considered in developing and evaluating N management measures

Demonstrasjonsprosjekt for implementering av EUs Vanndirektiv i Vansjø-Hobøl-vassdraget. Fase I

Med utgangspunkt i Vansjø-Hobøl-vassdraget presenteres forslag til aktuelle forvaltningssystemer og forvaltningsprosesser som kan benyttes ved implementeringen av Vanndirektivet i Norge. Rapporten inneholder også oversikt over aktuelle datasett, datamangler og databehov som kreves for implementering av direktivet, samt forslag til dataflyt mellom ulike aktører. Siste del av rapporten presenterer de viktigste belastningene og brukerinteressene i vassdraget og drøfter hvordan disse kan kvantifiseres i forhold til direktivets krav

Access pricing with regulated downstream competition and upstream externalities

We examine the optimal funding of farmers who have organised their activity in a cooperative that controls the supply of an input factor and meets competition in the market for its processed product. Since the rival's cost is private information, it may earn a rent. We show that the optimal price on the input factor -- the access price -- discriminates against the rival because rent is more valuable in the cooperative, and the regulator, therefore, sacrifices some cost efficiency in order to shift rents. The result is derived in a simplified context, but applies to contexts with more participants and products. Oxford University Press and Foundation for the European Review of Agricultural Economics 2010; all rights reserved. For permissions, please email [email protected], Oxford University Press.

Demonstrasjonsprosjekt for implementering av EUs Vanndirektiv i Vansjø-Hobøl. Fase 2: Skisse til veiledere for karakteriseringsoppgavene i 2004, samt forslag til overvåkingsprogram

Årsliste 2003Rapporten presenterer skisse til veiledning for karakterisering og overvåking av vannforekomster i hht. kravene i EUs Rammedirektiv for Vann. Metoder og kriterier for inndeling og typifisering av vannforekomster, samt for naturfaglig vurdering av risiko for dårlig status er foreslått. Metoder og datagrunnlag som er nødvendig for økonomisk karakterisering av vannbrukere og kostnadsdekking for vanntjenester er også presentert. Bruk av metodene er vist for Vansjø-Hobøl-vassdraget. Direktivets krav til overvåking av vannforekomster er sammenstilt, og forslag til overvåkingsprogram i tråd med disse kravene er foreslått for Vansjø-Hobøl-vassdraget. Ressursbehovet for gjennomføring av karakterisering og overvåking er estimert for dette vassdraget og forsøkt oppskalert til nasjonalt nivå.Direktoratsgruppen for Implementering av EUs Rammedirektiv for Van

Regional variations in diffuse nitrogen losses from agriculture in the Nordic and Baltic regions

This paper describes nitrogen losses from, and the characteristics of. 35 selected catchments (112 to 2000 ha) in the Nordic and Baltic countries. Average annual losses of N in 1994-1997 ranged from 5 to 75 kg ha(-1). Generally, the lowest losses were observed in the Baltic countries and the highest in Norway. The N losses were also characterised by significant within-country and interannual variations, particularly in the Norwegian catchments. An important finding of the study is that the average nutrient losses varied greatly among the catchments studied. The main explanations for this variability were water runoff, fertiliser use (especially the amount of manure), soil type and erosion (including stream bank erosion). However, there were several exceptions, and it was difficult to find general relationships between the individual factors. For example, there was poor correlation between nitrogen losses and surpluses. Therefore, the results suggest that the observed variability in N losses cannot have been due solely to differences in farm management practices, although the studied catchments do include a wide range of nutrient application levels, animal densities and other relevant elements. There is considerable spatial variation in the physical properties (soil. climate, hydrology, and topography) and the agricultural management of the basins, and the interaction between and relative effects of these factors has an important impact on erosion and nutrient losses. In particular, hydrological processes may have a marked effect on N losses measured in the catchment stream water. The results indicate that significant differences in hydrological pathways (e.g. the relationship between fast- and slow-flow processes) lead to major regional differences in N inputs to surface waters and therefore also in the response to changes in field management practices. Agricultural practices such as crop rotation systems, nutrient inputs and soil conservation measuresVytauto Didžiojo universitetasŽemės ūkio akademij

M2M Call Termination – Regulation or Competition?

We review the recent literature on mobile termination rates (MTR) in mobile communication networks (M2M). This literature shows that mobile networks may have incentives to charge ineficient high termination charges leading to reduced surplus for consumers and society, and therefore should be regulated. We discuss optimal regulation of MTRs and the two main objectives behind current regulation: excessive pricing and entry assistance. We also present a sketch of a new regulatory regime for the mobile industry