European landscapes contain a rich natural diversity that is cherished by many citizens. Protecti... more European landscapes contain a rich natural diversity that is cherished by many citizens. Protection of this diversity is laid down in policy strategies on European and national levels. Nevertheless, a recent review of the EU Biodiversity Strategy showed that additional efforts are needed to achieve the targets for 2020. Even more effort is required to realise the 2050 vision – which is to protect, value and restore EU biodiversity and the ecosystem services it provides. People consider ‘nature’ to constitute landscapes, ecosystems and biodiversity. Recent reviews and trend analyses have shown there to be three overall challenges for the coming decades, with respect to nature conservation: ensuring sufficient space and favourable conditions for nature, improving nature considerations in economic sectors, and encouraging people’s engagement in naturerelated efforts. For this study, we explored four ‘perspectives’ on nature in 2050, with the aim to inform a future agenda for nature pol...
Dankzij wetgeving voor gewasbescherming is de waterkwaliteit vooruit gegaan, al zijn de beleidsdo... more Dankzij wetgeving voor gewasbescherming is de waterkwaliteit vooruit gegaan, al zijn de beleidsdoelen voor de ecologische kwaliteit van het oppervlaktewater en voor de drinkwaterwinning niet bereikt. Ook bevat het oppervlaktewater op de helft van de meetlocaties nog te veel gewasbeschermingsmiddel. Wel zijn de beleidsdoelen voor voedselveiligheid en economie gehaald. De meeste zorg zit bij arbeidsveiligheid, vooral in de tuinbouw.
Throughout Europe, people experience and value nature in various ways, but they also experience t... more Throughout Europe, people experience and value nature in various ways, but they also experience the decline in biological diversity. Although successes have been achieved, nature policies have not been effective in all respects. Halting biodiversity loss and restoring ecological systems in the EU requires substantial action, in addition to current measures implemented under the EU Birds and Habitats Directives. More effective implementation, more coherence with other policies and greater engagement by other sectors and the public are needed. A closer connection between the ways in which people experience and value nature and nature policy may enhance their engagement in nature-related efforts. A more fundamental reflection on nature policies may be helpful. This has been done by PBL in its Nature Outlook study, which presents alternative ‘perspectives’ on the future of nature in the European Union. The synthesis report European nature in the plural1 is primarily intended to provide ...
Model LARCH is sinds 1996 weinig veranderd. Momenteel is het Milieu- en Natuurplanbureau een bela... more Model LARCH is sinds 1996 weinig veranderd. Momenteel is het Milieu- en Natuurplanbureau een belangrijke gebruiker, daarnaast zijn er de nodige toepassingen in het buitenland. Dit WOT Natuur & Milieu rapport geeft een analyse van wensen, mogelijkheden en ontwikkelingsrichtingen voor LARCH
Achtergrondinformatie bij hoofdstuk twee (Natuur, landschap en actoren) uit de Natuurbalans, een ... more Achtergrondinformatie bij hoofdstuk twee (Natuur, landschap en actoren) uit de Natuurbalans, een uitgave van het Natuurplanbureau
One of the sections in the fifth national environmental outlook deals with the influence of envir... more One of the sections in the fifth national environmental outlook deals with the influence of environmental quality on the ecological quality of nature in the Netherlands. This report documents the methods and calculations used and choices and assumptions made in exploring this influence on nature. Quantifying the influence was done by means of an 'environmental stress' indicator Environmental stress is defined as the decrease in possible occurrence of species due to environmental factors compared to a reference situation (1950). Besides the quantification, the relative importance of the environmental stress to the deterioration of ecosystems was calculated to indicate the most effective measures to improve nature quality. For several groups of species and environmental pressures the environmental stress was calculated with (multi-stress) models. In cases where models were not available (for some of the species groups and environmental pressures) expert judgement was used to d...
This English publication is an extended summary of the Dutch report that was published on 21 Sept... more This English publication is an extended summary of the Dutch report that was published on 21 September 2011. PBL has investigated adaptation options for the Netherlands to expected changes in climate and to weather extremes. Which options would be most effective to reduce flood risks? How could freshwater supplies be secured and the climate-resilience of nature and urban areas be improved?
Abstract. Surface waterblooms of toxic cyanobacteria (scums) interfere with the use of lakes, for... more Abstract. Surface waterblooms of toxic cyanobacteria (scums) interfere with the use of lakes, for instance in the production of drinking water or for recreation. Routine monitoring data are not sufficient for early warning due to the large temporal and spatial variability in the occurrence of surface waterblooms, and the time lag between the formation of the scum and the availability of relevant information for risk management. We combined a ‘‘traditional’’ dynamic simulation model based upon differential equations with fuzzy logic to describe the three main conditions governing surface waterbloom formation: (1) a preexisting population of cyanobacteria, (2) buoyancy of the cells, and (3) stability of the water column. The attributes and membership functions of the fuzzy model were based on earlier field studies of diel changes in buoyancy and vertical distribution of cyanobacteria. The model was applied without further calibration to the large lake IJsselmeer (1200 km2) in the Neth...
European landscapes contain a rich natural diversity that is cherished by many citizens. Protecti... more European landscapes contain a rich natural diversity that is cherished by many citizens. Protection of this diversity is laid down in policy strategies on European and national levels. Nevertheless, a recent review of the EU Biodiversity Strategy showed that additional efforts are needed to achieve the targets for 2020. Even more effort is required to realise the 2050 vision – which is to protect, value and restore EU biodiversity and the ecosystem services it provides. People consider ‘nature’ to constitute landscapes, ecosystems and biodiversity. Recent reviews and trend analyses have shown there to be three overall challenges for the coming decades, with respect to nature conservation: ensuring sufficient space and favourable conditions for nature, improving nature considerations in economic sectors, and encouraging people’s engagement in naturerelated efforts. For this study, we explored four ‘perspectives’ on nature in 2050, with the aim to inform a future agenda for nature pol...
Dankzij wetgeving voor gewasbescherming is de waterkwaliteit vooruit gegaan, al zijn de beleidsdo... more Dankzij wetgeving voor gewasbescherming is de waterkwaliteit vooruit gegaan, al zijn de beleidsdoelen voor de ecologische kwaliteit van het oppervlaktewater en voor de drinkwaterwinning niet bereikt. Ook bevat het oppervlaktewater op de helft van de meetlocaties nog te veel gewasbeschermingsmiddel. Wel zijn de beleidsdoelen voor voedselveiligheid en economie gehaald. De meeste zorg zit bij arbeidsveiligheid, vooral in de tuinbouw.
Throughout Europe, people experience and value nature in various ways, but they also experience t... more Throughout Europe, people experience and value nature in various ways, but they also experience the decline in biological diversity. Although successes have been achieved, nature policies have not been effective in all respects. Halting biodiversity loss and restoring ecological systems in the EU requires substantial action, in addition to current measures implemented under the EU Birds and Habitats Directives. More effective implementation, more coherence with other policies and greater engagement by other sectors and the public are needed. A closer connection between the ways in which people experience and value nature and nature policy may enhance their engagement in nature-related efforts. A more fundamental reflection on nature policies may be helpful. This has been done by PBL in its Nature Outlook study, which presents alternative ‘perspectives’ on the future of nature in the European Union. The synthesis report European nature in the plural1 is primarily intended to provide ...
Model LARCH is sinds 1996 weinig veranderd. Momenteel is het Milieu- en Natuurplanbureau een bela... more Model LARCH is sinds 1996 weinig veranderd. Momenteel is het Milieu- en Natuurplanbureau een belangrijke gebruiker, daarnaast zijn er de nodige toepassingen in het buitenland. Dit WOT Natuur & Milieu rapport geeft een analyse van wensen, mogelijkheden en ontwikkelingsrichtingen voor LARCH
Achtergrondinformatie bij hoofdstuk twee (Natuur, landschap en actoren) uit de Natuurbalans, een ... more Achtergrondinformatie bij hoofdstuk twee (Natuur, landschap en actoren) uit de Natuurbalans, een uitgave van het Natuurplanbureau
One of the sections in the fifth national environmental outlook deals with the influence of envir... more One of the sections in the fifth national environmental outlook deals with the influence of environmental quality on the ecological quality of nature in the Netherlands. This report documents the methods and calculations used and choices and assumptions made in exploring this influence on nature. Quantifying the influence was done by means of an 'environmental stress' indicator Environmental stress is defined as the decrease in possible occurrence of species due to environmental factors compared to a reference situation (1950). Besides the quantification, the relative importance of the environmental stress to the deterioration of ecosystems was calculated to indicate the most effective measures to improve nature quality. For several groups of species and environmental pressures the environmental stress was calculated with (multi-stress) models. In cases where models were not available (for some of the species groups and environmental pressures) expert judgement was used to d...
This English publication is an extended summary of the Dutch report that was published on 21 Sept... more This English publication is an extended summary of the Dutch report that was published on 21 September 2011. PBL has investigated adaptation options for the Netherlands to expected changes in climate and to weather extremes. Which options would be most effective to reduce flood risks? How could freshwater supplies be secured and the climate-resilience of nature and urban areas be improved?
Abstract. Surface waterblooms of toxic cyanobacteria (scums) interfere with the use of lakes, for... more Abstract. Surface waterblooms of toxic cyanobacteria (scums) interfere with the use of lakes, for instance in the production of drinking water or for recreation. Routine monitoring data are not sufficient for early warning due to the large temporal and spatial variability in the occurrence of surface waterblooms, and the time lag between the formation of the scum and the availability of relevant information for risk management. We combined a ‘‘traditional’’ dynamic simulation model based upon differential equations with fuzzy logic to describe the three main conditions governing surface waterbloom formation: (1) a preexisting population of cyanobacteria, (2) buoyancy of the cells, and (3) stability of the water column. The attributes and membership functions of the fuzzy model were based on earlier field studies of diel changes in buoyancy and vertical distribution of cyanobacteria. The model was applied without further calibration to the large lake IJsselmeer (1200 km2) in the Neth...
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