Monitoring van nationale ammoniakemissies uit de landbouw; op weg naar een verbeterde rekenmethodiek

De huidige rekenmethodiek voor het berekenen van de nationale ammoniakemissies uit landbouwkundige bronnen is aan een kritische analyse onderworpen. Aanleiding hiervoor was het grote verschil tussen de op directe wijze berekende ammoniakemissie uit deverschillende landbouwbronnen en de op indirecte wijze berekende emissie, afgeleid uit concentratiemetingen van ammoniak in lucht. De ammoniakemissies van de volgende bronnen zijn behandeld: de N-excretie van diergroepen, stal en buitenopslag van mest, mesttoediening op het land, kunstmest, beweiding en gewassen. Daarnaast is aandacht besteed aan de mestlogistiek, die van belang is voor de verdeling van geproduceerde mest over het bedrijf, binnen de regio en naar andere delen van Nederland. Aanbevelingen zijn gedaan voor de aanpassing van de huidige rekenmethodiek op de korte termijn en voor onderzoek dat na een aantal jaren moet leiden tot een structurele verbetering van de rekenmethodiek

Duurzame ontwikkeling van de landbouw in cijfers en ambities: Veranderingen tussen 2001 en 2006 (met bijdrage aan Hoofdstuk 3 van Eric Poot)

Deze bijdrage van Milieu- en Natuurplanbureau, CLM, LEI en Alterra behandelt de veranderingen in de landbouw. Gekeken wordt naar de aspecten: people, planet, profit; naar de veranderinge nide opgetreden zijn; en naar de afzonderlijke sectoren: akkerbouw, glastuinbouw, vollegrondsteelt, pluimveehouderij, varkenshouderij en melkveehouderi

Duurzame ontwikkeling van de landbouw in cijfers en ambities: Veranderingen tussen 2001 en 2006 (met bijdrage aan Hoofdstuk 3 van Eric Poot)

Deze bijdrage van Milieu- en Natuurplanbureau, CLM, LEI en Alterra behandelt de veranderingen in de landbouw. Gekeken wordt naar de aspecten: people, planet, profit; naar de veranderinge nide opgetreden zijn; en naar de afzonderlijke sectoren: akkerbouw, glastuinbouw, vollegrondsteelt, pluimveehouderij, varkenshouderij en melkveehouderi

Costs and effectiveness of on-farm measures to reduce aquatic risks from pesticides from the Netherlands

Background The European Union requires growers to implement the principles of Integrated Pest Management (IPM) by 2014. In this paper, we provide a quantitative overview of the costs and effectiveness of voluntary IPM measures in 15 crops in the Netherlands. We will focus on aquatic risks and define effectiveness as the potential to reduce the risks posed to aquatic organisms. We further identify which of these measures have actually been adopted by growers and why certain measures have not been adopted. Results Of the 105 measures evaluated, the most effective measures with respect to risk reduction were emission reduction and substitution of high-risk pesticides (each up to 80% reduction). IPM measures directed towards lowering pesticide use generally showed a smaller risk reducing potential. However, 40% of these measures reduced the overall cost of pest management. About 60% of all 105 measures were voluntarily implemented by growers. The most commonly adopted measures were pest prevention, low-dose spraying and spray drift reduction. Cost appeared to be an important incentive for adoption; however, other factors such as risk perception, education and practicability were equally important. Conclusions Voluntary IPM measures have significantly contributed to reducing aquatic risks (15-50% risk reduction depending on crop type). Further risk reduction could be achieved when more growers adopt the most effective measures like spray drift reduction and substitution of high-risk pesticides. However, IPM hardly reduced the number of pesticide applications and therefore the dependence on chemical crop protection continued to be high

Leaching of nitrate from agriculture to groundwater: the effect of policies and measures in the Netherlands

Nitrate concentrations in groundwater are correlated with the nitrogen surpluses at the soil surface. In the Netherlands, both nitrogen surpluses of agricultural land and nitrate concentrations in the groundwater of sandy soils are high. At present, nitrate concentrations in the groundwater of sandy soils exceed the 1980 EC Directive on the Quality of Water Intended for Human Consumption by a factor of 1 to 5. This paper discusses the effects of a series of policies and measures launched by the Dutchgovernment from 1986 onwards to decrease nitrogen losses to acceptable levels. Main focus is on the nitrogen and phosphorus accounting system MINAS, which will be implemented from 1998 onwards. The possible effects of the MINAS policy and measures on thenitrate contamination of groundwater have been examined via whole-farm analyses and simulation models, with a main focus on the nitrate leaky sandy soils and dairy farming systems. With MINAS, all farmers have to account for the nitrogen and phosphorus that is entering and leaving the farm. Further, MINAS includes charged and levy-free surpluses. The height of charges and the height of the levy-free surpluses together regulate the actual nitrogen surpluses at the farms. Levy-free nitrogen surpluses willbe lowered step-wise to 100 kg for arable land and 180 kg per ha for grassland in 2008. Following the implementation of the series of policy measures in the late eighties, data statistics indicate that the nitrogen surplus decreased from a mean of 347 kgper ha agricultural land 1985 to a mean of 299 kg per ha in 1995. Following the implementation of MINAS, our model predictions indicate that the nitrogen surplus at farm level will decrease further to a mean of 147 kg per ha in 2008, i.e. a reduction of 58% with reference to 1985. Mean nitrate concentrations at the average lowest groundwater level will decrease by 60%. Ultimately, 12% of the agricultural land (on sandy soils) will still have a nitrate concentration in the groundwater of more than 50 mg per litre. Our results indicate that MINAS is effective; they also indicate that additional measures are needed for agricultural land on dry sandy soils