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In order to successfully implement nature-based solutions as (part of) coastal defense, there is a need for insight into their efficiency and their reliability. The wave-attenuation capacity of vegetated coastal ecosystems like seagrasses and salt marshes has been widely studied. However, their stability on the medium to long term (i.e., engineering timescales) needs to be quantified. Key wave attenuating ecosystems like salt marshes have a high internal stability. However, their lateral extent is strongly influenced by the vertical (sediment) stability of adjacent mudflats and / or seagrass meadows. In this thesis the sediment stability thresholds of subtidal and lower intertidal ecosystems (from seagrass meadows up to tidal flats) under strong current and wave attack is quantified. Typically such thresholds are measured via field measurements or laboratory flume experiments. The problem with these approaches is, however, that field measurements lack hydrodynamic control, so thresholds can only be measured indirectly, and laboratory experiments require ecosystem transplantation or the use of mimics. Field flumes have therefore been developed as a way to generate controlled hydrodynamics in situ, and have been used to quantify sediment stability thresholds in seagrass meadows and on tidal flats (chapters 2 and 4). We explored the Seagrass – Sediment – Light (SSL) feedback by measuring sediment resuspension for various seagrass densities and sediment types (chapter 3). We were able to establish a general relation between seagrass density and sediment stability. This relation was then implemented in a simplified wave model which was used to assess the effects of changes in typical waves and storminess. We found that seagrasses are resilient to storms, but can be sensitive to changes in typical wind conditions depending on the topographical setting. Benthos influence the stability of tidal flats. This is a complex interaction, because there are many species which all act differently. The effects of different species can be generalized via their energy consumption. We tested this approach in the field, but we still found a large variability (chapter 4). Therefore, we conducted an experiment where we assessed how different combinations of highly contrasting species change sediment stability (chapter 5). We found that the species with the strongest individual effect overruled the effects of other species. When implementing nature-based solutions for coastal defense, there is a risk of accumulation of pollutants like microplastics. We assessed microplastic trapping within various biogenic habitats (chapter 6). We found that the susceptibility of a biogenic habitat to plastic accumulation was determined by their ability to reduce turbulence near the seabed. Furthermore, smaller particles are much more likely to be sequestered as they can ‘hide’ between larger sediment grains.

The societal and economic losses due to compound extremes, i.e., extreme events often result from one extreme state or amplification due to many other contributing mild or extreme states, are manifold higher in magnitude compared to the impacts of those from individual extremes alone. To understand the future impact of compound flood events at different spatio-temporal aggregation levels and climate zones, i.e., mountains, flood plains, and coasts, it is inevitable to examine the mechanisms of compound floods. To this end, this thesis highlights the importance of an integrated process-based physical modelling approach (atmospheric, hydrological and hydrodynamic) for the proper investigation of future flood risk. The research described in this thesis cover several relevant topics related to a complete flood risk chain (from mountains to coasts) and their impact on water resources in regions around the world (i.e., Europe and Asia). First part of this thesis focuses on empirical, univariate and bivariate approaches to understand historical climate trends and associated hazards in data scarce High Mountain Asia (HMA). This study provides a concise overiew of climate related changes across different regions which were difficult to align and compare either due to use of different data or spatio-temporal scales. Analysis reveals while the temperature is consistently increasing at a higher rate than the global warming rate, precipitation changes are not uniform, with substantial temporal and spatial variation in particular for the higher altitudes of HMA. Changes in climatic variables give rise to nonlinear, non-stationary, and non-uniform responses of cryospheric and hydrological variables such as snow, glaciers, soil moisture, and groundwater. Therefore, second part of this thesis investigates the systemic effect of the compound occurrence of extreme precipitation and temperature, at a wide range of spatio-temporal scales, and their impacts on the seasonality and trends in total water availability for HMA using a high-resolution cryospheric-hydrological model. This study shows a shift in the magnitude and peak of water availability, at seasonal time scale, to earlier in the year due to earlier onset of melting. Analysis reveals that the contrasting responses of HMA's rivers are primarily dictated by their hydrological regimes. To understand the risk due to compound floods in coastal regions, the third study of this thesis investigates the possibility of finding near-simultaneous storm surge and extreme river discharge along the Dutch coast using an extended dataset derived from a storm surge model and two hydrological river-discharge models forced with conditions from a high-resolution regional climate model in ensemble mode. This study conceptually shows that a strong storm whose winds set up a storm surge will need time to reach the Rhine headwaters where heavy rainfall will find its way to the river mouth after multiple days of travel time. The fourth and final study of this thesis investigates and quantifies the role of memory components in hydrological and meteorological systems which are responsible to generate extreme discharge, i.e. soil moisture, snow accumulation and the antecedent hydro-climatic conditions. Results show that the meteorological autocorrelation (manifesting itself by the occurrence of clustered precipitation events) has a strong impact on the magnitude of peak discharge. Finally, the study illustrates how hydrological memory from snow accumulation and soil moisture complements the generation of extreme discharges. A new valuable insight on the mechanisms of compound floods and its potential impact on water resources (both for historical and future climate) has been gained with novel modelling approaches. The outcomes generated from this thesis might contribute to support climate change adaptation policy planning and outreach programs in these climate change hotspots, i.e., the mountains and deltas.

The societal and economic losses due to compound extremes, i.e., extreme events often result from one extreme state or amplification due to many other contributing mild or extreme states, are manifold higher in magnitude compared to the impacts of those from individual extremes alone. To understand the future impact of compound flood events at different spatio-temporal aggregation levels and climate zones, i.e., mountains, flood plains, and coasts, it is inevitable to examine the mechanisms of compound floods. To this end, this thesis highlights the importance of an integrated process-based physical modelling approach (atmospheric, hydrological and hydrodynamic) for the proper investigation of future flood risk. The research described in this thesis cover several relevant topics related to a complete flood risk chain (from mountains to coasts) and their impact on water resources in regions around the world (i.e., Europe and Asia). First part of this thesis focuses on empirical, univariate and bivariate approaches to understand historical climate trends and associated hazards in data scarce High Mountain Asia (HMA). This study provides a concise overiew of climate related changes across different regions which were difficult to align and compare either due to use of different data or spatio-temporal scales. Analysis reveals while the temperature is consistently increasing at a higher rate than the global warming rate, precipitation changes are not uniform, with substantial temporal and spatial variation in particular for the higher altitudes of HMA. Changes in climatic variables give rise to nonlinear, non-stationary, and non-uniform responses of cryospheric and hydrological variables such as snow, glaciers, soil moisture, and groundwater. Therefore, second part of this thesis investigates the systemic effect of the compound occurrence of extreme precipitation and temperature, at a wide range of spatio-temporal scales, and their impacts on the seasonality and trends in total water availability for HMA using a high-resolution cryospheric-hydrological model. This study shows a shift in the magnitude and peak of water availability, at seasonal time scale, to earlier in the year due to earlier onset of melting. Analysis reveals that the contrasting responses of HMA's rivers are primarily dictated by their hydrological regimes. To understand the risk due to compound floods in coastal regions, the third study of this thesis investigates the possibility of finding near-simultaneous storm surge and extreme river discharge along the Dutch coast using an extended dataset derived from a storm surge model and two hydrological river-discharge models forced with conditions from a high-resolution regional climate model in ensemble mode. This study conceptually shows that a strong storm whose winds set up a storm surge will need time to reach the Rhine headwaters where heavy rainfall will find its way to the river mouth after multiple days of travel time. The fourth and final study of this thesis investigates and quantifies the role of memory components in hydrological and meteorological systems which are responsible to generate extreme discharge, i.e. soil moisture, snow accumulation and the antecedent hydro-climatic conditions. Results show that the meteorological autocorrelation (manifesting itself by the occurrence of clustered precipitation events) has a strong impact on the magnitude of peak discharge. Finally, the study illustrates how hydrological memory from snow accumulation and soil moisture complements the generation of extreme discharges. A new valuable insight on the mechanisms of compound floods and its potential impact on water resources (both for historical and future climate) has been gained with novel modelling approaches. The outcomes generated from this thesis might contribute to support climate change adaptation policy planning and outreach programs in these climate change hotspots, i.e., the mountains and deltas.

The societal and economic losses due to compound extremes, i.e., extreme events often result from one extreme state or amplification due to many other contributing mild or extreme states, are manifold higher in magnitude compared to the impacts of those from individual extremes alone. To understand the future impact of compound flood events at different spatio-temporal aggregation levels and climate zones, i.e., mountains, flood plains, and coasts, it is inevitable to examine the mechanisms of compound floods. To this end, this thesis highlights the importance of an integrated process-based physical modelling approach (atmospheric, hydrological and hydrodynamic) for the proper investigation of future flood risk. The research described in this thesis cover several relevant topics related to a complete flood risk chain (from mountains to coasts) and their impact on water resources in regions around the world (i.e., Europe and Asia). First part of this thesis focuses on empirical, univariate and bivariate approaches to understand historical climate trends and associated hazards in data scarce High Mountain Asia (HMA). This study provides a concise overiew of climate related changes across different regions which were difficult to align and compare either due to use of different data or spatio-temporal scales. Analysis reveals while the temperature is consistently increasing at a higher rate than the global warming rate, precipitation changes are not uniform, with substantial temporal and spatial variation in particular for the higher altitudes of HMA. Changes in climatic variables give rise to nonlinear, non-stationary, and non-uniform responses of cryospheric and hydrological variables such as snow, glaciers, soil moisture, and groundwater. Therefore, second part of this thesis investigates the systemic effect of the compound occurrence of extreme precipitation and temperature, at a wide range of spatio-temporal scales, and their impacts on the seasonality and trends in total water availability for HMA using a high-resolution cryospheric-hydrological model. This study shows a shift in the magnitude and peak of water availability, at seasonal time scale, to earlier in the year due to earlier onset of melting. Analysis reveals that the contrasting responses of HMA's rivers are primarily dictated by their hydrological regimes. To understand the risk due to compound floods in coastal regions, the third study of this thesis investigates the possibility of finding near-simultaneous storm surge and extreme river discharge along the Dutch coast using an extended dataset derived from a storm surge model and two hydrological river-discharge models forced with conditions from a high-resolution regional climate model in ensemble mode. This study conceptually shows that a strong storm whose winds set up a storm surge will need time to reach the Rhine headwaters where heavy rainfall will find its way to the river mouth after multiple days of travel time. The fourth and final study of this thesis investigates and quantifies the role of memory components in hydrological and meteorological systems which are responsible to generate extreme discharge, i.e. soil moisture, snow accumulation and the antecedent hydro-climatic conditions. Results show that the meteorological autocorrelation (manifesting itself by the occurrence of clustered precipitation events) has a strong impact on the magnitude of peak discharge. Finally, the study illustrates how hydrological memory from snow accumulation and soil moisture complements the generation of extreme discharges. A new valuable insight on the mechanisms of compound floods and its potential impact on water resources (both for historical and future climate) has been gained with novel modelling approaches. The outcomes generated from this thesis might contribute to support climate change adaptation policy planning and outreach programs in these climate change hotspots, i.e., the mountains and deltas.

The societal and economic losses due to compound extremes, i.e., extreme events often result from one extreme state or amplification due to many other contributing mild or extreme states, are manifold higher in magnitude compared to the impacts of those from individual extremes alone. To understand the future impact of compound flood events at different spatio-temporal aggregation levels and climate zones, i.e., mountains, flood plains, and coasts, it is inevitable to examine the mechanisms of compound floods. To this end, this thesis highlights the importance of an integrated process-based physical modelling approach (atmospheric, hydrological and hydrodynamic) for the proper investigation of future flood risk. The research described in this thesis cover several relevant topics related to a complete flood risk chain (from mountains to coasts) and their impact on water resources in regions around the world (i.e., Europe and Asia). First part of this thesis focuses on empirical, univariate and bivariate approaches to understand historical climate trends and associated hazards in data scarce High Mountain Asia (HMA). This study provides a concise overiew of climate related changes across different regions which were difficult to align and compare either due to use of different data or spatio-temporal scales. Analysis reveals while the temperature is consistently increasing at a higher rate than the global warming rate, precipitation changes are not uniform, with substantial temporal and spatial variation in particular for the higher altitudes of HMA. Changes in climatic variables give rise to nonlinear, non-stationary, and non-uniform responses of cryospheric and hydrological variables such as snow, glaciers, soil moisture, and groundwater. Therefore, second part of this thesis investigates the systemic effect of the compound occurrence of extreme precipitation and temperature, at a wide range of spatio-temporal scales, and their impacts on the seasonality and trends in total water availability for HMA using a high-resolution cryospheric-hydrological model. This study shows a shift in the magnitude and peak of water availability, at seasonal time scale, to earlier in the year due to earlier onset of melting. Analysis reveals that the contrasting responses of HMA's rivers are primarily dictated by their hydrological regimes. To understand the risk due to compound floods in coastal regions, the third study of this thesis investigates the possibility of finding near-simultaneous storm surge and extreme river discharge along the Dutch coast using an extended dataset derived from a storm surge model and two hydrological river-discharge models forced with conditions from a high-resolution regional climate model in ensemble mode. This study conceptually shows that a strong storm whose winds set up a storm surge will need time to reach the Rhine headwaters where heavy rainfall will find its way to the river mouth after multiple days of travel time. The fourth and final study of this thesis investigates and quantifies the role of memory components in hydrological and meteorological systems which are responsible to generate extreme discharge, i.e. soil moisture, snow accumulation and the antecedent hydro-climatic conditions. Results show that the meteorological autocorrelation (manifesting itself by the occurrence of clustered precipitation events) has a strong impact on the magnitude of peak discharge. Finally, the study illustrates how hydrological memory from snow accumulation and soil moisture complements the generation of extreme discharges. A new valuable insight on the mechanisms of compound floods and its potential impact on water resources (both for historical and future climate) has been gained with novel modelling approaches. The outcomes generated from this thesis might contribute to support climate change adaptation policy planning and outreach programs in these climate change hotspots, i.e., the mountains and deltas.

Second homes are a widespread part of the Swedish landscape and in many municipalities along the coastline the population can vary seasonally due to that. This cause planning issues for the municipalities, in how they plan their infrastructure, service etc. Studies has also shown that there are two sides in the discussion about second homes, some areas want to attract second home owners because they believe that this group help the municipality to grow while others try to attract permanent residents and restrict new development of second homes. The subject has been of discussion for a long time from many angels, for instance implementation of regulations to prevent second homes. The purpose of this thesis is to investigate what planning strategies municipalities apply in areas that change so heavily in population depending on season. The method for this thesis is based on a mixture between comparative analysis and content analysis of six comprehensive plans and two policy documents from six municipalities with archipelagos. Furthermore, from the content analysis of the different documents, three themes were produced from the strategies which then were compared in comparative analysis where similarities and differences were highlighted. The themes were population and housing, infrastructure and transport communication, service, business sector and labor. The analysis was subsequently put into context with related academic research such as urbanization theories, rural gentrification, planning theories among others. This ended with a discussion and conclusion. Conclusively the analysis show that municipalities no longer plan for second homes but for permanent residents, the municipalities believed that it is reactionary to plan for second home owners and not primary for permanent residents. Fritidsboende är en utbredd del av det svenska landskapet och i många kommuner längs kusten kan befolkningen variera säsongsmässigt på grund av det. Detta skapar viss planeringsproblematik för kommunerna i hur de planerar sin infrastruktur, service etc. Studier har också visat att det finns två sidor i diskussionen om fritidsbostäder, vissa områden vill locka fritidsboende eftersom de anser att denna grupp hjälper kommunen att utvecklas medan andra försöker locka permanenta invånare och begränsa ny utveckling av fritidsbostäder. Ämnet har diskuterats länge och från många vinklar, exempelvis implementering av regelverk för att förhindra fritidsbostäder. Syftet med detta examensarbete är att undersöka vilka planeringstrategier kommuner tillämpar i sådana områden som skiftar så kraftigt i befolkningen säsongsvis. Metoden i denna studie har bestått av en blandning mellan komparativ analys och innehållsanalys på sex översiktsplaner och två styrdokument gällande kust och skärgården från sex kust- och skärgårdskommuner Från innehållsanalysen av de olika dokumenten, producerades tre teman från de strategier som sedan jämfördes i den komparativa analysen, där likheter och skillnader lyfts fram. Teman var befolkning och bostäder, infrastruktur och kommunikation, service, näringsliv och arbetsmarknad. Analysen relaterades sedan till forskningsöversikten och den teoretiska utgångspunkten Detta avslutades med en diskussion och slutsats. Sammanfattningsvis visar analysen att kommunerna inte längre planerar för fritidsboende utan för fastboende, kommunerna menade att det är förlegat att planera för främst fritidsboende och inte fastboende.

A central question in this study is the evaluation and the improvement of the accuracy of wind-wave predictions in semi-enclosed seas. It was investigated how the parametrization of the wave models can be modified to provide accurate predictions in these specific areas. Furthermore, this work outlines how the physical inputs of the wave model such as the wind forcing and the bathymetry can affect wave predictions. An additional objective of this work is to assess the accuracy of the in-situ and remote field observations used in the calibration and validation processes of the numerical wave model. To examine these questions, wind-waves were simulated with the spectral wave model Simulating WAves Nearshore (SWAN) included in the Delft3D modelling package (Deltares, the Netherlands). Extensive calibration and validation of the wave model and its wind forcing were achieved by means of large datasets of in-situ and remote measurement technologies. Numerical predictions of wind-generated waves in two semi-enclosed seas, the Red Sea and the Bohai Sea were improved by means of modifications of the source term responsible of the generation of wave energy by wind in the action balance equation of the wave model. The findings provide support to the scientific community in the field of the operational oceanography. The outputs of the wave model for the Red Sea and the coastal waters of Jeddah were integrated into a coastal monitoring system. The wave model set up for the Bohai Sea is part of a Decision Support System for the Shandong peninsula. The two information systems provide hindcasts and forecasts of hydrodynamic parameters. Eine zentrale Frage in dieser Arbeit ist die Beurteilung und die Verbesserung der Genauigkeit von Vorhersagen für Windseen in halb geschlossenen Meeresgebieten. Es wurde untersucht wie die Parametrisierung des Wellenmodels modifiziert werden kann, um genaue Vorhersagen für die untersuchten Gebiete bereitzustellen. Außerdem umreißt diese Arbeit, wie die physikalischen Eingangsgrößen des Wellenmodells, der Windantrieb und die Bathymetrie die Vorhersage von Wellen beeinflussen können. Ein weiteres Ziel dieser Arbeit besteht darin, die Genauigkeit der In-Situ- und Fernerkundungsdaten einzuschätzen, die im Kalibrierungs- und Validierungsprozess des numerischen Modells benutzt wurden. Um diese Fragen zu untersuchen, wurden Windseen mit dem spektralen Wellenmodel Simulating WAves Nearshore (SWAN) simuliert, dass in der Modellierungssoftware Delft3D (Deltares, Holland) enthalten ist. Eine umfassende Kalibrierung und Validierung des Wellenmodells und seines Antriebs durch Wind wurde mit Hilfe großer Datensätze aus In-Situ- und Fernerkundungs-Meßtechniken erreicht. Numerische Vorhersagen von windgenerierten Wellen in zwei halb geschlossenen Meeresgebieten, dem Roten Meer und der Bohai See, wurden mit Hilfe von Modifikationen des Quellterms verbessert, der für die Erzeugung von Wellenenergie durch Wind in der Gleichung der spektrale Wirkungsdichte des Wellenmodels verantwortlich ist. Die Befunde liefern Unterstützung für die Wissenschaftler auf dem Gebiet der operativen Ozeanographie. Die Ergebnisse aus dem Wellenmodell für das Rote Meer und die Küstengewässer von Jeddah wurden in ein Küsten-Monitoring-System integriert. Das Wellenmodell, dass für die Bohai See aufgestellt wurde, ist ein Bestandteil eines Entscheidungshilfesystems (DSS) für die Shandong Halbinsel. Die beiden Informationssysteme stellen Hindcasts und Vorhersagen hydrodynamischer Parameter bereit.

Natural foreshores are shallow zones and beaches with a gradual slope and a (near-)natural vegetation that can be usedas an additional protection against flooding by reducing the wave attack on existing dikes, or can even completelyreplace an existing dike system. In order to test the applicability of this concept a 500 m long pilot section of a sandyforeshore was constructed along an already existing dike in the large shallow lake Markermeer, the Netherlands. Thepilot was equipped with permanent monitoring equipment for hydrodynamics and meteorological conditions and monthlysurveys of the morphology of the pilot section. These measurements will be carried out for the coming four years. Thispaper presents the first results after the construction and the first winter season with the pilot in place.

Natural foreshores are shallow zones and beaches with a gradual slope and a (near-)natural vegetation that can be usedas an additional protection against flooding by reducing the wave attack on existing dikes, or can even completelyreplace an existing dike system. In order to test the applicability of this concept a 500 m long pilot section of a sandyforeshore was constructed along an already existing dike in the large shallow lake Markermeer, the Netherlands. Thepilot was equipped with permanent monitoring equipment for hydrodynamics and meteorological conditions and monthlysurveys of the morphology of the pilot section. These measurements will be carried out for the coming four years. Thispaper presents the first results after the construction and the first winter season with the pilot in place.

Verspreiding, standplaats en vegetatie-opnamen van Hordeum marinum op kwelders in Noord-Friesland en Noordwest-Groningen. Het betreft een eenjarige grassoort, gebonden aan brakke tot zilte gebieden, die nu als bedreigde soort geldt

Als je bij zwaar weer over het strand wandelt, ervaar je de krachten van wind en zee aan den lijve. Als je dan bedenkt dat ruim 9 miljoen Nederlanders beneden de zeespiegel leven, besef je hoe kwetsbaar we eigenlijk zijn. Robuuste zeerepen, sterke zeedijken en met dammen afgesloten zeearmen houden de zee buiten de deur. Als we duinen en dijken blijven verhogen neemt de kans op een overstroming weliswaar af, maar mocht de zeewering onverhoopt doorbreken, dan zullen de gevolgen groter zijn dan ooit. Het is daarom tijd voor een duurzame benadering die ons minder kwetsbaar maakt. Dat kan door met de natuur mee te werken

Published by RIVM and the United Nations Environment Programme UNEP; Free of charge

Achtergrondrapport bij de Global Environment Outlook 3 van UNEP; ook gerelateerd aan Four Scenarios for Europe, RIVM 402001021

Achtergrondrapport bij de Global Environment Outlook 3 van UNEP; ook gerelateerd aan Four Scenarios for Europe, RIVM 402001021

Published by RIVM and the United Nations Environment Programme UNEP; Free of charge

With 80% of the world's population living in lowland urban areas by 2050, sea levels gradually rising and societal demands on the quality of living increasing, sustainable development of coastal zones becomes increasingly urgent as well as complex. Modern strategies for the design and implementation of measures for infrastructure development, coastal protection and other functions adopt the concept of Building with Nature to handle these challenges. Recently, two full scale experiments were implemented to assess the benefits of the this approach for coastal development. The Sand Motor pilot project addresses the potential concentrated nourishments on the basis of a 21 million m3 shore nourishment at the Delfland coast in the Netherlands. This unprecedented experiment aims to protect the hinterland from flooding by letting natural processes distribute sand over shoreface, beach and dunes, thus constituting a climate-robust and environmentally friendly way of coastal protection. The second experiment addresses the concept of seabed landscaping in sand extraction sites, which aims to add ecological value to the sand borrow areas after construction. Both pilots have been monitored since their completion in 2010/2011 and will be monitored extensively in the coming years.

With 80% of the world's population living in lowland urban areas by 2050, sea levels gradually rising and societal demands on the quality of living increasing, sustainable development of coastal zones becomes increasingly urgent as well as complex. Modern strategies for the design and implementation of measures for infrastructure development, coastal protection and other functions adopt the concept of Building with Nature to handle these challenges. Recently, two full scale experiments were implemented to assess the benefits of the this approach for coastal development. The Sand Motor pilot project addresses the potential concentrated nourishments on the basis of a 21 million m3 shore nourishment at the Delfland coast in the Netherlands. This unprecedented experiment aims to protect the hinterland from flooding by letting natural processes distribute sand over shoreface, beach and dunes, thus constituting a climate-robust and environmentally friendly way of coastal protection. The second experiment addresses the concept of seabed landscaping in sand extraction sites, which aims to add ecological value to the sand borrow areas after construction. Both pilots have been monitored since their completion in 2010/2011 and will be monitored extensively in the coming years.

Gedurende een jaar hebben onderzoekers de doorworteling van 19 zee- en rivierdijken geanalyseerd. Ze hebben daarin een seizoenspatroon waargenomen. Volgens hen is de beste periode voor toetsing van de doorworteling, nu medio december tot medio maart, van 1 oktober tot 1 maart.

Het concept ‘Bouwen met Natuur’ richt zich op gebiedsgerichte ontwerpprocessen langs kusten met het doel om de interactie tussen menselijke ingrepen en ecosysteem processen te vergroten. Het concept maakt maximaal gebruik van dynamiek van natuurlijke processen en van de inzet van bio@engineers bij de ontwikkeling van nieuwe kustlandschappen. De uitdaging bij ‘Bouwen met Natuur’ projecten is om een menselijke ambitie m.b.t. waterbouw te realiseren op een wijze die maximaal gebruik maakt van het ecosysteem en tevens dit ecosysteem versterkt. Het zoeken naar een win@win situatie voor zowel de menselijke waterbouwambitie als voor de natuurwaarden is dus iets anders dan natuur behouden die er is of nieuwe natuur ontwikkelen. Ook is het concept fundamenteel anders dan het compenseren van natuur die elders verloren gaat.

Het concept ‘Bouwen met Natuur’ richt zich op gebiedsgerichte ontwerpprocessen langs kusten met het doel om de interactie tussen menselijke ingrepen en ecosysteem processen te vergroten. Het concept maakt maximaal gebruik van dynamiek van natuurlijke processen en van de inzet van bio@engineers bij de ontwikkeling van nieuwe kustlandschappen. De uitdaging bij ‘Bouwen met Natuur’ projecten is om een menselijke ambitie m.b.t. waterbouw te realiseren op een wijze die maximaal gebruik maakt van het ecosysteem en tevens dit ecosysteem versterkt. Het zoeken naar een win@win situatie voor zowel de menselijke waterbouwambitie als voor de natuurwaarden is dus iets anders dan natuur behouden die er is of nieuwe natuur ontwikkelen. Ook is het concept fundamenteel anders dan het compenseren van natuur die elders verloren gaat.

Westnol op Noord-Beveland is het floristisch rijkste stukje zeedijk van Zuidwest-Nederland. Tot op zekeren hoogte ging het om een afscheidsbezoek. Dit element van de Oosterscheldekust stond aan de vooravond van een ingrijpende reconstructie, waarbij het nog maar de vraag was om hoeveel van de botanische rijkdom de werkzaamheden zou overleven. De overige excursiedoelen waren de werkeilanden Neetje Jans en Roggenplaat en het schor 't Stelletje bij Zierikzee

Westnol op Noord-Beveland is het floristisch rijkste stukje zeedijk van Zuidwest-Nederland. Tot op zekeren hoogte ging het om een afscheidsbezoek. Dit element van de Oosterscheldekust stond aan de vooravond van een ingrijpende reconstructie, waarbij het nog maar de vraag was om hoeveel van de botanische rijkdom de werkzaamheden zou overleven. De overige excursiedoelen waren de werkeilanden Neetje Jans en Roggenplaat en het schor 't Stelletje bij Zierikzee

I grunda vikar på svenska västkusten är snabbväxande makroalgsmattor vanligt förekommande under sommarhalvåret. Det faktum att förekomsten av algmattorna är positivt korrelerat till mängden organiskt material lagrat i sedimentet pekar på ett möjligt samband mellan algtillväxt och sedimentet som en självgenererande näringskälla. Sambandet indikerar att vissa typer av sediment är betydelsefulla näringskällor för denna algtillväxt. En metod för att minska närsaltsbelastningen som framförts är ett borttagande av ytsediment i dessa grunda havsvikar. I sjöar har muddring ofta använts som metod vid restaurering i syfte att minska den interna belastningen av näringsämnen (framförallt fosfor). Regionala inventeringsrapporter import från MDP 2015-05

Ten behoeve van een zandsuppletie op de kust van Ameland is een bestandsopname van de aanwezige macrofauna gemaakt in week 32 van 2009. Onderdeel van deze inventarisatie is een snelle bestandsopname van schelpdieren. De gegevens daarvoor zijn verzameld op 3 en 4 augustus 2009. Er is gebruikgemaakt van een gehuurd vaartuig bestemd voor de schelpdier visserij. Een totaal van 101 locaties is bemonsterd met een vanVeenhapper.

Zandsuppleties. Het programma “Ecologisch gericht suppleren, nu en in de toekomst” is een onderzoeks- en monitoringsprogramma voor de middellange termijn (2009-2014) met als doelstelling meer inzicht te krijgen of, en in welke mate, zandsuppleties van invloed zijn op natuurwaarden en op welke wijze zandsuppleties in de nabije toekomst kunnen bijdragen aan de opgaven van veiligheid samen met natuurbehoud en -ontwikkeling. Het programma moet leiden tot een optimalisatie van natuurbescherming van het kustecosysteem en een dynamisch beheer en behoud van de kustlijn.

Zandsuppleties. Het programma “Ecologisch gericht suppleren, nu en in de toekomst” is een onderzoeks- en monitoringsprogramma voor de middellange termijn (2009-2014) met als doelstelling meer inzicht te krijgen of, en in welke mate, zandsuppleties van invloed zijn op natuurwaarden en op welke wijze zandsuppleties in de nabije toekomst kunnen bijdragen aan de opgaven van veiligheid samen met natuurbehoud en -ontwikkeling. Het programma moet leiden tot een optimalisatie van natuurbescherming van het kustecosysteem en een dynamisch beheer en behoud van de kustlijn.

Ten behoeve van een zandsuppletie op de kust van Ameland is een bestandsopname van de aanwezige macrofauna gemaakt in week 32 van 2009. Onderdeel van deze inventarisatie is een snelle bestandsopname van schelpdieren. De gegevens daarvoor zijn verzameld op 3 en 4 augustus 2009. Er is gebruikgemaakt van een gehuurd vaartuig bestemd voor de schelpdier visserij. Een totaal van 101 locaties is bemonsterd met een vanVeenhapper.

Als je bij zwaar weer over het strand wandelt, ervaar je de krachten van wind en zee aan den lijve. Als je dan bedenkt dat ruim 9 miljoen Nederlanders beneden de zeespiegel leven, besef je hoe kwetsbaar we eigenlijk zijn. Robuuste zeerepen, sterke zeedijken en met dammen afgesloten zeearmen houden de zee buiten de deur. Als we duinen en dijken blijven verhogen neemt de kans op een overstroming weliswaar af, maar mocht de zeewering onverhoopt doorbreken, dan zullen de gevolgen groter zijn dan ooit. Het is daarom tijd voor een duurzame benadering die ons minder kwetsbaar maakt. Dat kan door met de natuur mee te werken

The third Global Environment Outlook (GEO-3) was published on the eve of the Johannesburg summit. At that moment in time (autumn 2002), GEO-3 looked back thirty years and forward thirty years. As set of what-if scenarios was used to explore the ways our society can advance, including implications for environmental and social goals. Characteristically, GEO-3 examines in a relatively deep fashion how its global scenarios can be interpreted in the context of each of the world's regions. This brochure presents the pan-European elaboration of the four GEO-3 scenarios: Markets First, Policy First, Security First and Sustainability First.

The third Global Environment Outlook (GEO-3) was published on the eve of the Johannesburg summit. At that moment in time (autumn 2002), GEO-3 looked back thirty years and forward thirty years. As set of what-if scenarios was used to explore the ways our society can advance, including implications for environmental and social goals. Characteristically, GEO-3 examines in a relatively deep fashion how its global scenarios can be interpreted in the context of each of the world's regions. This brochure presents the pan-European elaboration of the four GEO-3 scenarios: Markets First, Policy First, Security First and Sustainability First.

Het huidige rapport ‘Kustveiligheid en natuur’ presenteert de state of the art voor de gehele Nederlandse kust. Het behandelt de mogelijkheden van de combinatie van kustveiligheid en natuur, landschap en recreatie, voor de korte en de lange termijn, van lokale zandsuppleties tot grootschalige infrastructurele werken. Kustveiligheid en natuur zullen ook in de toekomst in de belangstelling blijven staan

Het huidige rapport ‘Kustveiligheid en natuur’ presenteert de state of the art voor de gehele Nederlandse kust. Het behandelt de mogelijkheden van de combinatie van kustveiligheid en natuur, landschap en recreatie, voor de korte en de lange termijn, van lokale zandsuppleties tot grootschalige infrastructurele werken. Kustveiligheid en natuur zullen ook in de toekomst in de belangstelling blijven staan

De kust van Voorne is aangemerkt als een zwakke schakel in de Hollandse Kust. Uit berekeningen blijkt dat de veiligheid tegen overstromingen onvoldoende is. Het waterschap Hollandse Delta – als beheerder van de waterkering – stelt een verbeteringsplan op voor de kust van Voorne. Voor dit verbeteringsplan wordt de procedure van de milieueffectrapportage (m.e.r.) doorlopen. De Commissie voor de m.e.r. in de gelegenheid gesteld om advies uit te brengen over de richtlijnen voor het milieueffectrapport

This report describes the derivation of parameter estimates for the model DYNAMIG for an arctic breeding shorebird, the Knot. DYNAMIG predicts the optimal spring migration of birds, like shorebirds and geese, that depend of a chain of discrete sites, to travel between their breeding grounds and their wintering grounds. An important parameter is the terminal reward, which describes the fitness consequences of arriving with a particular body condition at a particular time on the breeding grounds. We derived the terminal reward from field studies in Siberia carried out as part of this project. Other parameter values, like flight costs, maintenance metabolism and predation risk were derived from the literature. Predictions on aspects of the migration schedule with the parameterized model were partly correct and partly wrong. Suggestions are made how to remedy the discrepancies. An interesting prediction of the model that requires testing is that Knots breeding in Canada migrate via Iceland, whereas Knots breeding on Greenland migrate via Norway. A sensitivity analysis indicated that this prediction was quite robust.

In opdracht van RIKZ (Rijks Instituut voor Kust en Zee) is verkend welke ecologische en bestuurlijk-juridische inzichten gehanteerd kunnen worden op weg naar een meer geïntegreerd kustbeheer, waarbij zowel de landgedeelten als de ondiepe wateren in samenhang worden beschouwd ten dienste van een duurzame bestemming, inrichting en beheer. Ruimte-en tijdschalen van kusten en kustprocessen, maar ook de “span of control” van overheden zijn belangrijk. Gekeken is naar actuele en toekomstige ontwikkelingen, die een integrale aanpak vragen. Op grond van de analyse is aangegeven wat hoofd- en bijzaken zijn, waar kansen liggen voor verbetering van de ecologische situatie en wat bestuurlijk gezien gedaan kan worden om beleidsvoornemens effectief en efficiënt te kunnen realiseren. Voor integraal kustzonebeheer worden voorstellen gedaan

This report describes the derivation of parameter estimates for the model DYNAMIG for an arctic breeding shorebird, the Knot. DYNAMIG predicts the optimal spring migration of birds, like shorebirds and geese, that depend of a chain of discrete sites, to travel between their breeding grounds and their wintering grounds. An important parameter is the terminal reward, which describes the fitness consequences of arriving with a particular body condition at a particular time on the breeding grounds. We derived the terminal reward from field studies in Siberia carried out as part of this project. Other parameter values, like flight costs, maintenance metabolism and predation risk were derived from the literature. Predictions on aspects of the migration schedule with the parameterized model were partly correct and partly wrong. Suggestions are made how to remedy the discrepancies. An interesting prediction of the model that requires testing is that Knots breeding in Canada migrate via Iceland, whereas Knots breeding on Greenland migrate via Norway. A sensitivity analysis indicated that this prediction was quite robust.

Mangroves are a specific type of evergreen forest that is found along the coastlines of tropical and subtropical regions, particularly along deltas and bays where rivers discharge freshwater and sediment to the sea. These mangroves provide important ecological and socio-economic functions to coastal dwellers and societies. For example, they are natural spawning and living ground for many species of fish and crustaceans. Their timber benefits local people as construction material, firewood and charcoals and their marvelous root systems contribute to sediment deposition, mud flat formation and substrate stabilization. Thus, these forests also function as a shelter belt during storms, cyclones and tsunamis. This function was evident when the mangroves in Southern Thailand helped to mitigate the recent 2004 tsunami's devastation on lives and properties of the villages situated behind them.The present status of these valuable resources is critical, particularly in Southeast Asia, where the mangrove forest area is estimated to have declined by more than 50 percent over the past 35 years. The major causes of this loss were encroachment due to population expansion, conversion to aquaculture ponds, coastal erosion, lack of awareness and obscure or poorly enforced regulations, In Thailand, for example, recent satellite images show ample evidence of established and widespread aquaculture ponds along the coast of the Gulf of Thailand due to lack of restriction. More recently, government and public awareness of the importance of mangroves has risen, which has translated into several restoration and afforestation projects. Restoration of degraded mangrove areas was found to require much effort and encountered land-right problems. Therefore, many projects had switched to afforest on newly formed mudflats. Such projects, however, have met with variable success or failed to achieve the stated goals. This was probably because planting was carried out straightaway without carefully determining site-species suitability, appropriate planting technique as well as self-recovery or self-colonization capabilities from nearby stands.To obtain useful information for supporting sound mangrove and coastal zone management, this dissertation aims to gain a better understanding of mangrove (re)-colonization and factors effecting colonization success as well as factors underlying coastal changes. Firstly, the impact of sedimentation and water turbulence on seedling survival and growth of three common SE Asian mangrove taxa: Avicennia, Rhizophora and Sonneratia, were examined experimentally at the bay scale. Then, this research was broadened to assess the coastal dynamics of Southern Thailand by synthesizing data from coastal surveys over the period 1961-2000 along with field studies. Finally, simple demographic models were developed to simulate the mangrove colonization process.The two experiments reveal that after successful establishment on the mudflat, seedlings were susceptible to mortality due to sudden high sediment burial and water turbulence. Mortality was found to increase with increasing sediment accretion and none of Avicennia seedlings was able to survive under the highest experimental burial of32 cm while those of Rhizophora and Sonneratia still showed substantial survival (30% and 60%, respectively). Among the three taxa, Sonneratia was the least affected due to burial and exhibited a rapid growth rate. Seedlings of Rhizophora survived less m highly exposed plots (low neighboring plant density) than in sheltered ones. In contrast, survival of Avicennia and Sonneratia seedlings were higher at more exposed plots. This finding confirms the behavior of Avicennia and Sonneratia as pioneer species that may colonize unoccupied mudflat and Rhizophora as a successor. It a!so suggests a higher success of the first two species in re-colonization. However, in areas where sudden high sediment loads are possible, Sonneratia might be better able to cope with burial than Avicennia.The assessment of changes along Southern Thai coastlines revealed that the coast of the Gulf of Thailand had undergone more change than the western side of the peninsula. Ongoing erosion occurred irregularly at the high energy coastal segments and was observed along 29% and 11% of the total coastal length of the east and the west coasts, respectively. Subsequent total area loss accounted for 116 ha annually (91 and 25 ha for the east and the west coasts, respectively). Factors responsible for coastal erosion were found to be mangrove area loss, increase of shrimp farming area, less sediment delivery to coastal area due to upstream river damming and exposure to fetch from the monsoonal wind. Erosion was less in mangrove-dominated coastlines, and progression occurred mainly in sheltered and mangrove-dominated coastal segments. Areal progress accounted for 37 ha per annum on the east and 5 ha on the west coasts. Thus, summed over the whole of Southern Thailand, a net erosion of 74 ha y-1 was observed over the past three decades. These results also reveal that the existence and progression of the mangroves as well as sufficient sediment supply to coastal area contributed significantly to coastal stability.Thirty-year runs of the demographic simulation model revealed that herbivory and water turbulence were the main factors influencing the success of colonization in a mangrove-dominated bay while gradual sedimentation and salinity had little effect. Avicennia was the most successful taxon in colonizing open mudflats followed by Sonneratia while Rhizophora exhibited less success. However, colonization success may vary with changes in environmental conditions as revealed by our predictive scenarios. For example, accelerated sea level rise will reduce the success in colonization of all three taxa and lack of freshwater discharge due to river damming may enhance the colonization success of Avicennia but adversely affect Sonneratia.Overall, this study suggests that success in re-colonization of mangroves depends on both ecological and hydrological factors. Seedling herbivory and water turbulence are important factors that may seriously hinder colonization success. Also, the three taxa studied were found to differ critically in colonization capacity. Gradual sedimentation has little effect on mangrove colonization but positive sedimentation provides habitats for mangrove to colonize, particularly, in sheltered coastal segments. Less sediment delivery due to upstream river damming associated with conversion of mangrove and beach forest to aquaculture ponds will probably intensify coastal erosion in vulnerable areas. Therefore, managers should pay more attention to the balance between ecological and socio-economic demands for sustainable development of the coastal zone.

De kust van Voorne is aangemerkt als een zwakke schakel in de Hollandse Kust. Uit berekeningen blijkt dat de veiligheid tegen overstromingen onvoldoende is. Het waterschap Hollandse Delta – als beheerder van de waterkering – stelt een verbeteringsplan op voor de kust van Voorne. Voor dit verbeteringsplan wordt de procedure van de milieueffectrapportage (m.e.r.) doorlopen. De Commissie voor de m.e.r. in de gelegenheid gesteld om advies uit te brengen over de richtlijnen voor het milieueffectrapport

In opdracht van RIKZ (Rijks Instituut voor Kust en Zee) is verkend welke ecologische en bestuurlijk-juridische inzichten gehanteerd kunnen worden op weg naar een meer geïntegreerd kustbeheer, waarbij zowel de landgedeelten als de ondiepe wateren in samenhang worden beschouwd ten dienste van een duurzame bestemming, inrichting en beheer. Ruimte-en tijdschalen van kusten en kustprocessen, maar ook de “span of control” van overheden zijn belangrijk. Gekeken is naar actuele en toekomstige ontwikkelingen, die een integrale aanpak vragen. Op grond van de analyse is aangegeven wat hoofd- en bijzaken zijn, waar kansen liggen voor verbetering van de ecologische situatie en wat bestuurlijk gezien gedaan kan worden om beleidsvoornemens effectief en efficiënt te kunnen realiseren. Voor integraal kustzonebeheer worden voorstellen gedaan

Mangroves are a specific type of evergreen forest that is found along the coastlines of tropical and subtropical regions, particularly along deltas and bays where rivers discharge freshwater and sediment to the sea. These mangroves provide important ecological and socio-economic functions to coastal dwellers and societies. For example, they are natural spawning and living ground for many species of fish and crustaceans. Their timber benefits local people as construction material, firewood and charcoals and their marvelous root systems contribute to sediment deposition, mud flat formation and substrate stabilization. Thus, these forests also function as a shelter belt during storms, cyclones and tsunamis. This function was evident when the mangroves in Southern Thailand helped to mitigate the recent 2004 tsunami's devastation on lives and properties of the villages situated behind them.The present status of these valuable resources is critical, particularly in Southeast Asia, where the mangrove forest area is estimated to have declined by more than 50 percent over the past 35 years. The major causes of this loss were encroachment due to population expansion, conversion to aquaculture ponds, coastal erosion, lack of awareness and obscure or poorly enforced regulations, In Thailand, for example, recent satellite images show ample evidence of established and widespread aquaculture ponds along the coast of the Gulf of Thailand due to lack of restriction. More recently, government and public awareness of the importance of mangroves has risen, which has translated into several restoration and afforestation projects. Restoration of degraded mangrove areas was found to require much effort and encountered land-right problems. Therefore, many projects had switched to afforest on newly formed mudflats. Such projects, however, have met with variable success or failed to achieve the stated goals. This was probably because planting was carried out straightaway without carefully determining site-species suitability, appropriate planting technique as well as self-recovery or self-colonization capabilities from nearby stands.To obtain useful information for supporting sound mangrove and coastal zone management, this dissertation aims to gain a better understanding of mangrove (re)-colonization and factors effecting colonization success as well as factors underlying coastal changes. Firstly, the impact of sedimentation and water turbulence on seedling survival and growth of three common SE Asian mangrove taxa: Avicennia, Rhizophora and Sonneratia, were examined experimentally at the bay scale. Then, this research was broadened to assess the coastal dynamics of Southern Thailand by synthesizing data from coastal surveys over the period 1961-2000 along with field studies. Finally, simple demographic models were developed to simulate the mangrove colonization process.The two experiments reveal that after successful establishment on the mudflat, seedlings were susceptible to mortality due to sudden high sediment burial and water turbulence. Mortality was found to increase with increasing sediment accretion and none of Avicennia seedlings was able to survive under the highest experimental burial of32 cm while those of Rhizophora and Sonneratia still showed substantial survival (30% and 60%, respectively). Among the three taxa, Sonneratia was the least affected due to burial and exhibited a rapid growth rate. Seedlings of Rhizophora survived less m highly exposed plots (low neighboring plant density) than in sheltered ones. In contrast, survival of Avicennia and Sonneratia seedlings were higher at more exposed plots. This finding confirms the behavior of Avicennia and Sonneratia as pioneer species that may colonize unoccupied mudflat and Rhizophora as a successor. It a!so suggests a higher success of the first two species in re-colonization. However, in areas where sudden high sediment loads are possible, Sonneratia might be better able to cope with burial than Avicennia.The assessment of changes along Southern Thai coastlines revealed that the coast of the Gulf of Thailand had undergone more change than the western side of the peninsula. Ongoing erosion occurred irregularly at the high energy coastal segments and was observed along 29% and 11% of the total coastal length of the east and the west coasts, respectively. Subsequent total area loss accounted for 116 ha annually (91 and 25 ha for the east and the west coasts, respectively). Factors responsible for coastal erosion were found to be mangrove area loss, increase of shrimp farming area, less sediment delivery to coastal area due to upstream river damming and exposure to fetch from the monsoonal wind. Erosion was less in mangrove-dominated coastlines, and progression occurred mainly in sheltered and mangrove-dominated coastal segments. Areal progress accounted for 37 ha per annum on the east and 5 ha on the west coasts. Thus, summed over the whole of Southern Thailand, a net erosion of 74 ha y-1 was observed over the past three decades. These results also reveal that the existence and progression of the mangroves as well as sufficient sediment supply to coastal area contributed significantly to coastal stability.Thirty-year runs of the demographic simulation model revealed that herbivory and water turbulence were the main factors influencing the success of colonization in a mangrove-dominated bay while gradual sedimentation and salinity had little effect. Avicennia was the most successful taxon in colonizing open mudflats followed by Sonneratia while Rhizophora exhibited less success. However, colonization success may vary with changes in environmental conditions as revealed by our predictive scenarios. For example, accelerated sea level rise will reduce the success in colonization of all three taxa and lack of freshwater discharge due to river damming may enhance the colonization success of Avicennia but adversely affect Sonneratia.Overall, this study suggests that success in re-colonization of mangroves depends on both ecological and hydrological factors. Seedling herbivory and water turbulence are important factors that may seriously hinder colonization success. Also, the three taxa studied were found to differ critically in colonization capacity. Gradual sedimentation has little effect on mangrove colonization but positive sedimentation provides habitats for mangrove to colonize, particularly, in sheltered coastal segments. Less sediment delivery due to upstream river damming associated with conversion of mangrove and beach forest to aquaculture ponds will probably intensify coastal erosion in vulnerable areas. Therefore, managers should pay more attention to the balance between ecological and socio-economic demands for sustainable development of the coastal zone.

Philippinesis endowed with many natural resources but it is also confronted with a climate that annually poses threats to livelihood, food and nutrition security of its populace. High incidence of poverty and a great variation in agro-ecological setting influence food production as well as economic conditions continue to affect the country's food and nutrition security. The seasonal pattern of rainfall causes fluctuations in aspects of life, such as seasonal labor needs in agriculture and fishery, fluctuations in food security and variations in nutritional status. The present study was carried out in two different ecological settings: a lowland area inCentral Luzonand a coastal area on theislandofLeyte(Visayas).This study was aimed at examining the factors influencing food and nutrition security at the household and individual level and establish the magnitude of food and nutrition insecurity. In this study, child malnutrition was placed in the context of the food security situation and livelihood performance of households with pre-school children. While putting the child malnutrition issues in the wider context of food and livelihood security, a number of research questions were raised and answered in the different chapters.The first research question dealt with the factors influencing household food security and child malnutrition. Food insecurity and child malnutrition are quite common in both areas but the relationship between the two differs according to ecological setting, which in turn is differentiated by sources of income, living conditions, ownership of assets, and habitual diet. This study reveals that in wage-earning households in the lowland area, child malnutrition is less related to income and food availability than among households in the coastal area, where food and nutrition security more or less coincide. Above the food security threshold, care and morbidity are the limiting factors to nutrition security of households. This implies that while livelihood security is a pre-condition to food security, the presence of both does not always lead to better quality diets of children. Livelihood security may coincide with food security but the two do not automatically result in nutrition security in the population studied. The absence of an association of food security indicators with malnutrition suggests that different processes operate for food security and nutrition security. The relation between income and food security is context- and location-specific, with livelihood strategies as intervening variables.In this study, there appeared to be a clear difference in the evolution and type of malnutrition between the lowland and coastal area. Biological adjustments in the growth of children were noted. In the lowland area, children are short but have adequate weight-for-height, while in the coastal areas, aside from being stunted, preschool children are also wasted. These findings suggest that in the lowland area, the direct determinants of child malnutrition, which include breastfeeding, complementary food, morbidity and care, are more important than household food security. In the coastal area, high prevalence of wasting points to more prominence of food insecurity as an important determinant of child malnutrition.The second research question focused on people's ideas about food security. There are gender differences in men and women's ideas of food security. Because of their traditional role as breadwinner, men view food security in terms of stable income (livelihood) and food supply. They consider food security as being part and parcel of livelihood security. Women have broader perspective of food security. Traditionally, women are the homemakers. Their ideas of food security hinge on food sufficiency through proper management of the household's scarce resources.The third research question dealt with the qualitative changes in dietary pattern and sources of food as indicators of seasonal changes in household food security. Rice is the only staple food throughout the year in the lowland villages, while - in different proportions by season - rice and corn are eaten in the coastal area. The period of relative abundance in the lowland area as well as in the coastal area falls in the dry season. This is reflected in the lowest prevalence of food shortage in both areas during this period. However, coastal villages experience a longer period of scarcity (five months) than lowland villages (three months). While only fifty percent of households reported periodical food shortages, in general, the habitual diets were of poor quality, irrespective of the season.Research question four focused on the coping behavior of households in the two study areas. In both areas, households use a number of strategies and coping mechanisms to prevent seasonal food stress and meet actual food needs. Actions intended to solve the problem of food security in the long-term include income diversification and mobilization of assets to prevent an impending food crisis. However, my study revealed that diversifying economic activities and/or seeking new ways of livelihood generation have potential only when skills as well as jobs and other resources are available and accessible to the households.Aside from preventive strategies, several adaptive or coping mechanisms were observed. These include: mortgaging, inter-household transfers, barter, altering food preparation, cutting down on the number of meals, gathering wild foods, and - to some extent - postponing expenditures on health. Apparently, there are differences in coping strategies used by men and women, which can be attributed to their culturally determined different roles in the household. Women are highly visible in activities to meet actual food needs, while men generally dominate in income diversification and resource mobilization activities. The research shows that in both areas type, timing and sequence of actions and strategies of men and women vary according to the conditions and the degree of vulnerability that characterize the household at the start of the food crisis.Research question five dealt with gender issues. Power relations in decision-making on resource allocation and in productive and reproductive activities of men and women were examined. In both areas, men make more decisions than women. Men, being the head of the household, decide on matters related to investments and livelihood. As part of their reproductive role, women decide on matters concerning care and management and allocation of resources related to food procurement, preparation, distribution, and consumption. The study notes that in times of economic hardship and food crisis, women carry out specific coping activities. However, there appears to be a shift in the division of tasks between men and women, when the workload is high and women have to combine reproductive activities and working for the market. Then, men sometimes take over part of the reproductive workload of their wife. Nevertheless, findings suggest that indeed there are unequal distribution of roles and unequal division of labor between the male and female.The sixth research question focused on the role of the BIDANI program in improving livelihood, food and nutrition security. BIDANI is the acronym of Barangay Integrated Development Approach for Nutrition Improvement. It is a nation-wide extension program working through a network of state universities and colleges. As a program and a strategy BIDANI can serve as a catalyst to enhance the capability and capacity of the different stakeholders to address food problems. The comprehensive and "bottom-up" approach of BIDANI is important for enhancing local livelihood, food and nutrition security. This study shows, however, that the linkages between the three types of security cannot be taken for granted; that the one does not automatically lead to the other.BIDANI can contribute to decreasing malnutrition prevalence in real life situations. Its various intervention and development projects, including micro-credit, can produce synergistic impacts that improve nutrition. The women's income-generation activities can serve as useful vehicle for the diversification of the livelihood portfolio of the target households, which can have favorable effects on the coping ability of household. However, there are structural factors underlying the lack of livelihood security, as is apparent from the differences between the situation in the lowland and coastal villages, that for BIDANI are difficult to address. Looking at alternatives, integrated development based on the primary sector (agriculture and fishery) must be complemented by employment opportunities in other sectors to reduce poverty. Off-farm employment and the generation of jobs are a challenge for local governments and BIDANI. Being a dynamic program, BIDANI can adjust its focus to incorporate more systematically issues concerning employment and income, family size, and women's reproductive rights and health.