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Recent climate warming is disproportionately impacting the Arctic. Over the last decades, the Arctic is warming nearly four times faster than the global average. This has a significant local and global impact, for example through thaw and destabilisation of permafrost, the ‘permanently’ frozen ground below the Arctic. Thaw of permafrost reintroduces the soil organic carbon (OC) it holds into the short-term carbon cycle. This OC, when mobilised by thaw and subject to degradation, can be a significant source of greenhouse gases. However, redeposition and storage of permafrost OC in river- and marine sediments can attenuate this ‘permafrost carbon feedback’. It is still poorly understood whether lateral transport of permafrost OC through aquatic systems will strengthen this feedback through degradation of OC along the way, or weaken it through burial of OC in sediments. The objective of this thesis is to assess the fate of permafrost OC in aquatic systems. We will start from the source, and move along the path the permafrost OC takes to its destination in an integrated approach, and assess what is left and what is lost along its journey. We will combine sedimentological (grain size, mineral surface area) and geochemical analyses (elemental C and N, molecular biomarkers, and carbon isotopes δ13C and radiocarbon) on samples from the source (permafrost thaw sites), transitional environments (rivers, thaw slumps, nearshore zone), the marine shelf and marine basins to assess the degradation, deposition, and transport potential of permafrost OC along the land-to-ocean continuum, on both a small scale (5 km, Herschel Island – Herschel Basin, Yukon, Canada) and a large scale transect (1500 km, Kolyma River – East Siberian Sea, North East Siberia, Russia). This thesis highlights that every pool of OC needs to be included when studying the pathway and destination of permafrost OC on a land-ocean transect: dissolved in water (DOC), as particulate matter (POC), and within the soil and sediments (SOC). This type of integrated carbon cycle-approach is necessary for both river and marine studies, where we should consider that each pool of permafrost OC is ‘processed’ at a different stage along its journey, and acknowledge the complex and dynamic interactions between different carbon pools along the way. We find that the transitional zones play a crucial role for processing permafrost OC: particularly the zone between ‘undisturbed’ permafrost and ‘thaw-mobilised’ permafrost material (e.g. the thaw slumps, thaw streams, mudpools), and the zone on the border of land and ocean, (e.g. the nearshore zone for coastal erosion or the delta for larger rivers). Furthermore, we find that the combination of biogeochemical and sedimentological methods is especially necessary when comparing samples from different sedimentary environments, and recommend further integration of these methods. Sorting of OC during transport through deposition and resuspension, and the affinity of certain types of OC to mineral particles through adsorption and desorption can affect biomarker proxies for degradation just as well as actual degradation.

Recent climate warming is disproportionately impacting the Arctic. Over the last decades, the Arctic is warming nearly four times faster than the global average. This has a significant local and global impact, for example through thaw and destabilisation of permafrost, the ‘permanently’ frozen ground below the Arctic. Thaw of permafrost reintroduces the soil organic carbon (OC) it holds into the short-term carbon cycle. This OC, when mobilised by thaw and subject to degradation, can be a significant source of greenhouse gases. However, redeposition and storage of permafrost OC in river- and marine sediments can attenuate this ‘permafrost carbon feedback’. It is still poorly understood whether lateral transport of permafrost OC through aquatic systems will strengthen this feedback through degradation of OC along the way, or weaken it through burial of OC in sediments. The objective of this thesis is to assess the fate of permafrost OC in aquatic systems. We will start from the source, and move along the path the permafrost OC takes to its destination in an integrated approach, and assess what is left and what is lost along its journey. We will combine sedimentological (grain size, mineral surface area) and geochemical analyses (elemental C and N, molecular biomarkers, and carbon isotopes δ13C and radiocarbon) on samples from the source (permafrost thaw sites), transitional environments (rivers, thaw slumps, nearshore zone), the marine shelf and marine basins to assess the degradation, deposition, and transport potential of permafrost OC along the land-to-ocean continuum, on both a small scale (5 km, Herschel Island – Herschel Basin, Yukon, Canada) and a large scale transect (1500 km, Kolyma River – East Siberian Sea, North East Siberia, Russia). This thesis highlights that every pool of OC needs to be included when studying the pathway and destination of permafrost OC on a land-ocean transect: dissolved in water (DOC), as particulate matter (POC), and within the soil and sediments (SOC). This type of integrated carbon cycle-approach is necessary for both river and marine studies, where we should consider that each pool of permafrost OC is ‘processed’ at a different stage along its journey, and acknowledge the complex and dynamic interactions between different carbon pools along the way. We find that the transitional zones play a crucial role for processing permafrost OC: particularly the zone between ‘undisturbed’ permafrost and ‘thaw-mobilised’ permafrost material (e.g. the thaw slumps, thaw streams, mudpools), and the zone on the border of land and ocean, (e.g. the nearshore zone for coastal erosion or the delta for larger rivers). Furthermore, we find that the combination of biogeochemical and sedimentological methods is especially necessary when comparing samples from different sedimentary environments, and recommend further integration of these methods. Sorting of OC during transport through deposition and resuspension, and the affinity of certain types of OC to mineral particles through adsorption and desorption can affect biomarker proxies for degradation just as well as actual degradation.

As vertrekpunt vir hierdie artikel word Suid-Afrika beskryf as 'n ontwikkelingstaat, tans onderworpe aan 'n proses van demokratiese konsolidasie. Hierdie onafgehandelde proses word direk verbind aan die oorgang vanaf 'n ou (apartheids-) na 'n nuwe (demokratiese) bedeling. In hierdie opsig word Suid-Afrika dan ook ingesluit onder die definisie van 'n transformasionele staat. Die term "transformasionele demokrasie" verwys vervolgens na 'n demokrasie wat tot stand gekom het as gevolg van 'n bevrydingstryd, en getransformeer het vanaf 'n outokratiese of koloniale regime na 'n konstitusionele staatsorde. Daar word geargumenteer dat daar in vele opsigte voldoen is aan die vereistes van prosedurele transformasie ná 1994, met die aanvaarding van die grondwet in 1996 en die instelling van konstitusioneel-demokratiese strukture en instansies, en veral die hervorming van die regstelsel en die instelling van vrye en regverdige verkiesings. In terme van substantiewe transformasie bly die proses egter nog onafgehandel. Dit is juis hierdie gebrek aan substantiewe transformasie wat gelei het tot 'n afname in kiesersdeelname en kiesersvertroue. Teen hierdie agtergrond is die oogmerk van die artikel om die effek van die erosie van kiesersvertroue op die politieke landskap en die uiteindelike proses van sowel historiese as huidige demokratiese konsolidasie in Suid-Afrika te bepaal. Ten einde hierdie doel te bereik word daar eerstens, op 'n holistiese wyse, gefokus op die rol van die staat in moderne ontwikkelende demokrasieë. Tweedens word die artikel vernou tot die aard van kiesersvertroue in gevestigde en trans-formasionele demokrasieë. Teen hierdie kontekstuele agtergrond word derdens gefokus op die Suid-Afrikaanse situasie. Hier word spesifiek verwys na die stygende trajek van onder-steuning vir die ANC in nasionale en plaaslike verkiesings tussen 1994 en 2004, met daarteenoor die moontlike oorsake vir die afname in ondersteuning vir die ANC-regering ná 2004. Terselfdertyd word die afname in stemopkoms reeds sedert die verkiesing in 1999 in teenstelling tot die groeiende stemouderdompopulasie (SOP) tot en met die nasionale verkiesing in 2019 onder die soeklig geplaas. Met die oog op die projeksie van 'n toekoms-scenario rakende politieke konsolidasie word die daling in stemopkoms en die onderliggende erosie van kiesersvertroue in die Suid-Afrikaanse politieke landskap, ter afsluiting, in verband gebring met mislukkings in die bereiking van veral substantiewe ontwikkelingsdoelwitte en -uitkomste. Internationally, voter trust in political systems is recognised as key to successful democratic governance and the effective co-ordination of collective interaction between government and civil society. For the purposes of this article, it is inferred that voter trust is largely based on the ability of the government to bring about successful transformation in a developmental society - within a period of time. Voter trust in the ANC originally showed increased levels in the first decade of democracy. However, after the 2004 election levels of voter trust started eroding in the ANC; in fact, since the 1999 elections voter trust has been consistently eroding in the South African democracy as a whole. In order to identify the nature and causes of this phenomenon, this article will focus primarily on the following narrative: the failure of transitional governments to implement effectively election promises in the substantive dimensions of the democracy and the effect of said failure on voter behaviour and trust. Based on these guidelines, the purpose of the article is therefore to identify the causes of the erosion of voter trust in the macro (ethical and moral), meso (economic) and application (social) dimensions of the democracy. The primary objective will be to establish the influence such erosion of voter trust has had on the ruling party, election outcomes and the democratic consolidation process generally in South Africa. To illustrate the trajectory of the erosion in voter trust, voting patterns from the post-1994 period to 2016 are discussed. The results ofvarious analytical studies regarding voting patterns were applied to substantiate the argument that the trajectory of voter trust in the ANC government at first reflected an increase, as opposed to the erosion thereof in the second decade of democracy and beyond. The analysis of voting patterns, especially under the so-called "born free" generation, revealed voter apathy, low political efficacy and the erosion of trust in the governing party, leaders, institutions and democratic processes. Various studies revealed that participation of the VAP (Voting Age Population) in elections from 1994 to 2004 was already on a downward trajectory since 1999 through to 2016. Urbanisation and the change in socio-economic needs of voters, as well as the ideological shift in their viewpoint from democratic ideals (freedom and equality) to bread and butter issues, coupled with the government's inability to eliminate poverty, rendered the original election message of liberation and the ANC as the only legitimate government, increasingly irrelevant in the last decade of democracy. Analysis of the implementation of election promises, as stipulated in the ANC manifestos, show that there were successes at procedural level in terms of the establishment of democratic institutions, but that the ANC was mostly ineffective in its management thereof (substantive implementation), and therefore failed in the establishment of socio-economic and interventional programmes and policies. The appearance of corruption, clientelism, maladministration and state capture is manifest not only in the ANC government structures, but also in democratic institutions, State Owned Enterprises (SOE's) and Nongovernmental Organisations (NGO's). Voter trust in a democracy follows a dynamic process where political (moral) trust is initially high, shifting to institutional trust (economic) in the transitional phase along with interpersonal trust (social), as democratic consolidation and acceptance of democratic principles (as the only legitimate form of government) are being established. Delay in democratic consolidation places the focus on interpersonal trust as voters become more concerned over issues such as basic service delivery, poverty alleviation, housing and jobs (personal wellbeing). In this article it is assumed that a downward turn in voter trust negatively affects democratic consolidation. All three dimensions of voter trust are required in equal balance for the democracy to consolidate successfully within a set period of time. In conclusion, recommendations are made, including a vision towards future trends in voter trust in the aftermath of the 2019 national/provincial elections.

Een dataset bestaande uit SCADA data van drie windturbines. Daarbij toegevoegd data van de Dutch Offshore Wind Atlas zodat deze in verband gebracht kan worden met de SCADA data. Als laatst is ook een klein praktisch onderzoek opgenomen. Dat onderzoekt aan de hand van machine learning of er op basis van de dataset kan worden geconcludeerd of er erosie aan de turbinebladen plaats heeft gevonden. NB: de dataset is gevoelig voor concurrentie. Daarom is de dataset geanonimiseerd en zijn de data dusdanig aangepast dat deze niet naar de reëele data en exploitant herleidbaar zijn.

Door klimaatverandering verandert het afvoerregime van onze grote rivieren. Hoogwaters worden hoger en frequenter, laagwaters lager en langduriger. Hoe we daarop reageren hangt af van hoe we klimaatverandering zien: als opgave, of als kans om onvolkomenheden aan te pakken. In dit artikel presenteren we aanzetten voor een meer geo-ecologisch gefundeerde inrichting, of – naar McHarg – voor design with nature.Climate change is expected to significantly influence the discharge regime of the Rhine and Meuse rivers. Floods may increase in magnitude and occur more frequently; low discharges are likely to become even smaller and last longer. How to respond to those changes? Can all river functions be fulfilled into the future and which interventions are then needed to keep the country safe and the rivers navigable? The answer to these questions depends on whether climate change is primarily considered as a challenge, or rather as an opportunity to, at the same time, redress a few deficiencies and detrimental geo-ecological developments that are being provoked by how we straightjacketed our floodplains and engineered our rivers in behalf of navigation but negatively impact biodiversity. We propose a more geo-ecologically grounded approach to our rivers’ spatial design and management – inspired by McHarg’s design with nature –, which encompasses making available much more room for safe flood discharge and reduced hydrodynamics for ecosystem development in the floodplains, as well as more nature-based river training to allow for morphological developments and natural rejuvenation.

Door klimaatverandering verandert het afvoerregime van onze grote rivieren. Hoogwaters worden hoger en frequenter, laagwaters lager en langduriger. Hoe we daarop reageren hangt af van hoe we klimaatverandering zien: als opgave, of als kans om onvolkomenheden aan te pakken. In dit artikel presenteren we aanzetten voor een meer geo-ecologisch gefundeerde inrichting, of – naar McHarg – voor design with nature.Climate change is expected to significantly influence the discharge regime of the Rhine and Meuse rivers. Floods may increase in magnitude and occur more frequently; low discharges are likely to become even smaller and last longer. How to respond to those changes? Can all river functions be fulfilled into the future and which interventions are then needed to keep the country safe and the rivers navigable? The answer to these questions depends on whether climate change is primarily considered as a challenge, or rather as an opportunity to, at the same time, redress a few deficiencies and detrimental geo-ecological developments that are being provoked by how we straightjacketed our floodplains and engineered our rivers in behalf of navigation but negatively impact biodiversity. We propose a more geo-ecologically grounded approach to our rivers’ spatial design and management – inspired by McHarg’s design with nature –, which encompasses making available much more room for safe flood discharge and reduced hydrodynamics for ecosystem development in the floodplains, as well as more nature-based river training to allow for morphological developments and natural rejuvenation.

In regions with a Nordic climate, soil erosion rates in winter and early spring can exceed those occurring during other seasons of the year. In this context, this study was initiated to improve our understanding of the interaction between agricultural soils and occurring winter conditions. The main objective was to better understand how hydrological processes in a catchment are influenced by snow, ice, and freeze-thaw cycles of soils, leading to runoff and soil erosion in winter and spring conditions. For this purpose, detailed spatially and temporally distributed measurements and observations in a small catchment in Norway were executed during three consecutive winter/spring periods. During the winter/spring periods of 2013-2014, 2014-2015 and 2015-2016, soil water content, soil temperature, and snow cover properties were measured. In addition, numerous soil samples were taken to determine the soil hydraulic characteristics of the investigated soils and to quantify the changes in their macropore networks due to freeze-thaw events, using X-ray imaging. With the collected data and deduced process understanding, it was possible to model and quantify the spatial and temporal development of snow packs. Furthermore, the field observations revealed how the interaction of tillage, state of the soils and snow cover at a certain time can lead to none or extensive surface runoff and soil erosion. Integrating acquired data, observations and process knowledge facilitated advances in simulating and quantifying surface runoff and soil erosion rates across the catchment under investigation. The models applied and the maps and output derived are crucial elements for presenting current state and problems in the catchment to stakeholders (such as farmers), providing a starting point for discussing ways to prevent and reduce further runoff and erosion. For model calibration and validation, including interpretation of modelling results, good knowledge of the area and availability of detailed data are essential, especially when processes such as freezing-thawing of soils and ice layer and snow-pack dynamics have to be considered also. In order to reduce runoff and soil erosion during winter and snowmelt conditions in the future, more targeted research is required in order to address the full range of existing knowledge gaps in this field, as identified in this particular study also.

Op de oostelijke helft van wierde Grote Houw bij Leens is onderzoek gedaan naar de snelheid van erosieprocessen. Deze wierde bevat archeologische resten uit de vroege en volle middeleeuwen en heeft een zeer hoge archeologische waarde. Het doel van dit onderzoek dat tussen 2012 en 2014 plaatsvond, was om te onderzoeken hoe intensief de erosieprocessen zijn die deze vindplaats bedreigen. Verschillende technieken werden ingezet om de snelheid van erosie te bepalen. Ook zijn er nieuwe rekenmethodes ontwikkeld. Naast informatie over de snelheid van erosie op dit terrein, leverde het veldwerk ook nieuwe informatie op over de opbouw en ouderdom van de wierde en over de verspreiding van archeologische resten op het terrein. De Grote Houw Oost is één van de vier locaties waar in het kader van het TOPsites project onderzoek is uitgevoerd naar de snelheid van erosie. Doel van het project TOPsites is om wettelijk beschermde archeologische monumenten te beschermen tegen de effecten van sluipende degradatie.

De Rapportage Archeologische Monumentenzorg beschrijft de resultaten van het veldonderzoek op het archeologisch rijksmonument Tjessens bij Waaxens in de gemeente Dongeradeel, uitgevoerd tussen 2013 en 2015. Tjessens is een van rijkswege beschermd archeologisch monument. Het terrein bestaat uit een (dorps-)terp met daarin resten van een stins en de latere state Tjessens. De resten van de terp en state waren tot voor kort vanwege de aanwezigheid van overigens deels verlande watergangen – waarschijnlijk voormalige grachten – nog in het terrein herkenbaar, evenals de toegangsweg tot het stateterrein. Een deel van het gebruik van het terrein wordt omgezet van grasland naar akkerland. Het andere deel is al als akkerland in gebruik. De vraag is wat de effecten van deze omzetting zijn en wat dit betekent voor de fysieke kwaliteit van het monument. Het onderzoek komt voort uit het project TOPsites van de Rijksdienst voor het Cultureel Erfgoed dat zich richt op het in kaart brengen van degradatie en aantasting van verschillende typen wettelijk beschermde archeologische monumenten.

Op de oostelijke helft van wierde Grote Houw bij Leens is onderzoek gedaan naar de snelheid van erosieprocessen. Deze wierde bevat archeologische resten uit de vroege en volle middeleeuwen en heeft een zeer hoge archeologische waarde. Het doel van dit onderzoek dat tussen 2012 en 2014 plaatsvond, was om te onderzoeken hoe intensief de erosieprocessen zijn die deze vindplaats bedreigen. Verschillende technieken werden ingezet om de snelheid van erosie te bepalen. Ook zijn er nieuwe rekenmethodes ontwikkeld. Naast informatie over de snelheid van erosie op dit terrein, leverde het veldwerk ook nieuwe informatie op over de opbouw en ouderdom van de wierde en over de verspreiding van archeologische resten op het terrein. De Grote Houw Oost is één van de vier locaties waar in het kader van het TOPsites project onderzoek is uitgevoerd naar de snelheid van erosie. Doel van het project TOPsites is om wettelijk beschermde archeologische monumenten te beschermen tegen de effecten van sluipende degradatie.

Erosieve gebitsslijtage is een veel voorkomend verschijnsel onder de jeugd en jongvolwassenen in Nederland. Aandacht voor dit probleem is vanwege de irreversibele gevolgen noodzakelijk. Het vragenlijstonderzoek (als onderdeel van ‘Tandheelkundig Onderzoek en Praktijk Noord Nederland’) dat werd uitgevoerd onder 331 jongvolwassenen (20 tot en met 25 jaar) uit 25 mondzorgpraktijken, had als doel inzicht te verkrijgen in het kennisniveau over erosieve gebitsslijtage en in door de jongvolwassenen meest gewenste manier om tandheelkundige informatie te ontvangen. Uit de resultaten bleek dat er nog veel onbekend is over erosieve gebitsslijtage onder jongvolwassenen, waarbij de kennisscore afhankelijk was van opleidingsniveau en het eerder hebben ontvangen van informatie hierover. Een gesprek met een mondzorgverlener, ondersteund door schriftelijke informatie op maat, werd door de deelnemers als meest gewenste manier van informeren aangegeven.

In Kelmond is onderzocht hoe snel erosie en nivellering de archeologische vindplaats aantast en welke maatregelen er nodig zijn om (verdere) schade te beperken. Grond zonder vegetatie is gevoelig voor erosie. Ploegwerkzaamheden zorgen daarbij voor vervlakking en nivellering van reliëfverschillen. Dat dit schadelijk is voor archeologische vindplaatsen is bekend, maar detailinformatie over hoe snel de conditie van de archeologie achteruitgaat, is er niet. In het kader van het project TOPsites van de Rijksdienst voor het Cultureel Erfgoed, zijn vijf locaties geselecteerd voor onderzoek. Er is opzettelijk gekozen voor plekken waarvan de verwachting is dat erosie/nivellering zo sterk is, zodat ze kunnen worden gezien als worst-case scenario. In deze Rapportage Archeologische Monumentenzorg (RAM) wordt verslag gedaan van een veldonderzoek uit 2012-2014 bij Beek in het buurtschap Kelmond.

Erosieve gebitsslijtage is een veel voorkomend verschijnsel onder de jeugd en jongvolwassenen in Nederland. Aandacht voor dit probleem is vanwege de irreversibele gevolgen noodzakelijk. Het vragenlijstonderzoek (als onderdeel van ‘Tandheelkundig Onderzoek en Praktijk Noord Nederland’) dat werd uitgevoerd onder 331 jongvolwassenen (20 tot en met 25 jaar) uit 25 mondzorgpraktijken, had als doel inzicht te verkrijgen in het kennisniveau over erosieve gebitsslijtage en in door de jongvolwassenen meest gewenste manier om tandheelkundige informatie te ontvangen. Uit de resultaten bleek dat er nog veel onbekend is over erosieve gebitsslijtage onder jongvolwassenen, waarbij de kennisscore afhankelijk was van opleidingsniveau en het eerder hebben ontvangen van informatie hierover. Een gesprek met een mondzorgverlener, ondersteund door schriftelijke informatie op maat, werd door de deelnemers als meest gewenste manier van informeren aangegeven.

De Rapportage Archeologische Monumentenzorg beschrijft de resultaten van het veldonderzoek op het archeologisch rijksmonument Tjessens bij Waaxens in de gemeente Dongeradeel, uitgevoerd tussen 2013 en 2015. Tjessens is een van rijkswege beschermd archeologisch monument. Het terrein bestaat uit een (dorps-)terp met daarin resten van een stins en de latere state Tjessens. De resten van de terp en state waren tot voor kort vanwege de aanwezigheid van overigens deels verlande watergangen – waarschijnlijk voormalige grachten – nog in het terrein herkenbaar, evenals de toegangsweg tot het stateterrein. Een deel van het gebruik van het terrein wordt omgezet van grasland naar akkerland. Het andere deel is al als akkerland in gebruik. De vraag is wat de effecten van deze omzetting zijn en wat dit betekent voor de fysieke kwaliteit van het monument. Het onderzoek komt voort uit het project TOPsites van de Rijksdienst voor het Cultureel Erfgoed dat zich richt op het in kaart brengen van degradatie en aantasting van verschillende typen wettelijk beschermde archeologische monumenten.

Het Zuid-Limburgse heuvellandschap is gevoelig voor erosie. Op proefboerderij Wijnandsrade werken onderzoekers al dertig jaar aan het bestrijden van dit voor Nederland unieke en complexe probleem. „En we zijn nog altijd niet klaar”, stelt PPO-onderzoeker Gerard Meuffels.

De overstromingen in de Birmese Irrawaddy delta afgelopen mei en ontruiming van New Orleans in verband met orkaan Gustav in september maken ons nog een keer duidelijk hoe riskant bewoning van een deltaplan is. Delta's zijn zeer aantrekkelijk vanwege hun natuurlijke hulpbronnen, maar ook uitermate kwetsbaar. De Nijldelta loopt jaarlijks ruim 120 miljoen ton vers sediment mis vanwege de stroomopwaarts gelegen Aswan-dam

Pesticide use and off-site risk assessment: a case study of glyphosate fate in Chinese Loess soil Xiaomei Yang Abstract: Repeated applications of pesticide may contaminate the soil and water, threatening their quality within the environmental system and beyond it through water erosion related processes and leaching. Taking into account the situation of intense farming, pesticide use and erosion in China, and in the loess area in particular, this study aims to further the science of pesticide risk assessment by increasing the understanding of the fate of glyphosate and its main metabolite AMPA while also assessing their risks related to soil erosion in Chinese loess soil. Four main objectives are conducted: 1) Assessment of farmers’ knowledge and awareness of pesticide use in the Wei River catchment In this study, we presented the information for the knowledge and awareness of pesticide risks via face-to-face interview among farmers (209) and retailers (20) in two rural regions (Qianyang County (S1) and Chencang County (S2)) of the Wei River catchment in China where the modes of farming and the state of erosion are very different. The results showed that farmers learned about the use and risk related to of pesticide use mainly by oral communication (p70%) was the most common mode of personal hygiene after spraying, comparing to wearing masks, showering, and changing clothes. Regarding to dealing with the packages or containers of pesticide, farmers dumped them directly onto the land or into water, and over 85% of farmers claimed to use illegal pesticides. Compared to farmers, pesticide retailers were well-informed and highly conscious of their responsibility for the safe use of pesticides. Educational programmes targeted to age groups, proper disposal of pesticide waste, and sufficient supervision from authorities should consequently be considered for improving the levels of knowledge and awareness of the dangers of pesticides to human health and environmental pollution in the Wei River catchment, China. 2) Investigation of off-site transport of glyphosate and AMPA by runoff and erosion in Chinese loess soil In this study, we assessed the short-term transport (1h duration, 1 mm min-1 rainfall) of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) related to erosion and runoff on bare loess soil with different slopes (10° and 20°)and application rates (3.6 kg ha-1 and 7.2 kg ha-1) in hydraulic flumes. Significant power and exponent function described a significantly negative relation between rainfall duration and the content of glyphosate and AMPA (p

Pesticide use and off-site risk assessment: a case study of glyphosate fate in Chinese Loess soil Xiaomei Yang Abstract: Repeated applications of pesticide may contaminate the soil and water, threatening their quality within the environmental system and beyond it through water erosion related processes and leaching. Taking into account the situation of intense farming, pesticide use and erosion in China, and in the loess area in particular, this study aims to further the science of pesticide risk assessment by increasing the understanding of the fate of glyphosate and its main metabolite AMPA while also assessing their risks related to soil erosion in Chinese loess soil. Four main objectives are conducted: 1) Assessment of farmers’ knowledge and awareness of pesticide use in the Wei River catchment In this study, we presented the information for the knowledge and awareness of pesticide risks via face-to-face interview among farmers (209) and retailers (20) in two rural regions (Qianyang County (S1) and Chencang County (S2)) of the Wei River catchment in China where the modes of farming and the state of erosion are very different. The results showed that farmers learned about the use and risk related to of pesticide use mainly by oral communication (p70%) was the most common mode of personal hygiene after spraying, comparing to wearing masks, showering, and changing clothes. Regarding to dealing with the packages or containers of pesticide, farmers dumped them directly onto the land or into water, and over 85% of farmers claimed to use illegal pesticides. Compared to farmers, pesticide retailers were well-informed and highly conscious of their responsibility for the safe use of pesticides. Educational programmes targeted to age groups, proper disposal of pesticide waste, and sufficient supervision from authorities should consequently be considered for improving the levels of knowledge and awareness of the dangers of pesticides to human health and environmental pollution in the Wei River catchment, China. 2) Investigation of off-site transport of glyphosate and AMPA by runoff and erosion in Chinese loess soil In this study, we assessed the short-term transport (1h duration, 1 mm min-1 rainfall) of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) related to erosion and runoff on bare loess soil with different slopes (10° and 20°)and application rates (3.6 kg ha-1 and 7.2 kg ha-1) in hydraulic flumes. Significant power and exponent function described a significantly negative relation between rainfall duration and the content of glyphosate and AMPA (p

Erosie en depositie worden in hoge mate bepaald door enkele (heftige) regenbuien, zeker in Mediterrane semi-aride gebieden zoals Spanje. In landschapsevolutie spelen dezelfde processen een belangrijke rol, maar kijken we naar de effecten van die processen over duizenden jaren, bijvoorbeeld de vorming van rivier terrassen. Er zit een groot gat in tijdschaal tussen de regenbuien enerzijds (uren-dagen) en landschapsevolutie anderzijds. Hebben enkele (heftige) regenbuien nog invloed op landschapsevolutie en zo ja, op welke manier? Of is het cumulatieve effect van het grotere aantal kleinere buien uiteindelijk meer bepalend voor hoe het landschap zich ontwikkeld? De afgelopen 5 jaar heb ik me tijdens promotie-onderzoek bezig gehouden met dit thema. Het resultaat, mijn proefschrift, heb ik afgelopen 9 mei succesvol verdedigd aan de Wageningen Universiteit. Een overzicht van mijn onderzoek en de belangrijkste resultaten: 5 jaar in 3 pagina's!

The problem of roaming livestock is a major impediment to agricultural development and nature conservation on St. Eustatius, as it also typically is on other islands in the region. In support of a government-led culling program, we here conducted a baseline study of livestock abundance and distribution on the island in the final quarter of 2013.

The problem of roaming livestock is a major impediment to agricultural development and nature conservation on St. Eustatius, as it also typically is on other islands in the region. In support of a government-led culling program, we here conducted a baseline study of livestock abundance and distribution on the island in the final quarter of 2013.

Existing definitions of “soil quality” and “sustainable land management” are analysed to derive a procedure for defining land quality (LQ) indicators of sustainable land management. Land — rather than soil qualities are considered to reflect the impact of the climate on soil behaviour. LQ is different for different types of land use and attention is arbitrarily confined here to agriculture. Simulation modelling of crop growth and solute fluxes is used to define LQ as the ratio between a conditioned crop yield and potential yield×100. The actual agro-ecological condition and its potential, both expressed by LQ for a given piece of land, is considered here as independent input into broader land-use discussions which tend to be dominated by socio-economic and political considerations. Agro-ecological considerations should not be held hostage to actual socio-economic and political considerations which may change in the near future while the LQ has a much more permanent character. The proposed LQ reflects yields, risks of production as simulations are made for many years, and soil and water quality associated with the production process. The latter are expressed here in an exploratory manner for seven tropical soils and in more detail for Dutch conditions in terms of the probability that groundwater is polluted with nitrates, reflecting the most dominant current LQ problem. The proposed procedure requires the selection of acceptable production and pollution risks by the user before a LQ value can be obtained. Existing definitions implicitly emphasise the field and farm level. However, LQ is also important at the regional and higher level which, so far, has received little attention. Then, again, an agro-ecological approach is suggested when defining the LQ as input into the planning process, emphasising not only an independent assessment of the potential for agricultural production, but also of nature conservation.

Changing land use is increasingly known to affect on-site landscape properties, nevertheless off-site effects are often neglected. A single process landscape evolution model (LandscApe ProcesS modelling at mUlti dimensions and scaleS (LAPSUS)) is used to explore the impacts of land use changes on landscape and soil properties. Examples are shown for both on-site as well as off-site effects of land use change and the influence of different pathways of change. A case study area near Alora, in the province of Malaga, south Spain is selected. In this area the main land use consists of citrus, olive/almond, wheat, semi-natural vegetation and a rest group (bare, river beds, urban). For a period of 10 years LAPSUS calculates soil redistribution (erosion and sedimentation) for different scenarios of input parameters. These inputs are a digital elevation model (e.g. slope lengths and angles), precipitation, soil erodibility, and land use related infiltration. For each scenario, different assumptions are made on direction and rate of land use change. As an example, effects of abandonment of olive orchards are demonstrated, simulating both a fast and gradual change for a period of 10 years. Each scenario produces different spatial and temporal patterns of total amounts of erosion and sedimentation throughout the landscape. As a result, potential land use related parameters like soil depth, infiltration and flooding risk change significantly too. The scenario of an abrupt change produces the highest erosion rates compared to the gradual change scenario and the baseline scenario. However, because of the multi-dimensional characteristics of the landscape, not only the area suffering from land use changes is affected. Increasing erosion and run-off rates from upstream-located olive orchards have an impact on down slope local run-on, erosion and sedimentation rates. In this case, the citrus orchards situated in the valley bottom locally suffer damages from re-sedimentation events but benefit from the increase in run-on water and nutrients. Concluding, off-site effects from an exogenous driven change in land use (EC subsidies) can trigger endogenous land use changes in adjacent areas.

Major changes in land use may be anticipated in Europe in the decades to come as a result of technological, socio-economic and political developments as well as global environmental change. The type and effects of these changes will strongly depend on policy decisions which are governed, amongst others, by: (i) an increasing agricultural productivity; (ii) an increasing realization of the need to conserve bio-diversity and environmental quality for current and future generations; (iii) pressure from an increasingly urban population to emphasize non-agricultural forms of land use in terms of nature and landscape conservation; (iv) increasing market-driven demand for high quality produce made with environmentally friendly forms of management; and (v) increasing food demand on the world market as the world population doubles and purchasing powers increases, particularly in Asia. These developments occur now both in Eastern and Western Europe, even though historical developments during the last 50 years have been strikingly different in these two regions. Collectivization in Eastern Europe after World War II was associated with higher yields but also with unfavourable changes in land use and cropping patterns causing acidification, soil erosion, salinization and chemical pollution. The change to democracy in the late 1980s implied a change from an essentially quantity- to a more quality-oriented type of agriculture, like in Western Europe where an industrialized agriculture had also caused environmental problems. Emphasis is now being placed on rational land use, which includes optimization of farm size and the development and implementation of economically viable crop production techniques which result in high quality produce as well as limited adverse environmental side effects. However, these ideals are far from being realized. According to some studies, the technical possibilities of modern agriculture can theoretically in future provide an adequate volume of produce from only 30 to 50% of the current agricultural area in western Europe. This implies potential for other forms of land use in the remaining land area. However, other studies emphasizing low external input agriculture or extrapolation of historical trends, indicate that the current land area may be needed to produce adequate food, certainly when considering the future world market demand. This conclusion is also supported by the fact that theoretical production levels are often much higher than real levels, because of various agronomic and socio-economic factors. A major challenge for the decades ahead is to avoid uncontrolled developments of land use with possibly adverse socio-economic and environmental effects; the latter include the time-delayed release of harmful chemicals, currently held in some soils, into the environment and the enhanced emission of radiatively active trace gases from soils to atmosphere. Controlled developments yielding sustainable forms of agricultural land use in some areas and nature development in others, is to be preferred and should ideally be based on eco-regional approaches. The authors advocate initiation of comprehensive, exploratory studies for Europe in which sustainable production of major land units is defined as a function of different types of land management and in which Europe is seen as part of the world economy. Six exploratory studies are reviewed in this paper; however, none of these scenario studies has the necessary comprehensive character and none is based on adequate land data.

Soil degradation is occurring over vast areas. The GLASOD and ASSOD projects reflect the present status of human-induced soil degradation and its impact on food productivity related to productivity changes observed in the recent past. However, there is a great need for well-documented, reliable soil information and other related data at national and regional levels to better understand and qualify the impact of changing soil conditions or biomass production.

The Limburg Soil Erosion Model (LISEM) is a physically based model incorporated in a raster geographical information system. This incorporation facilitates easy application in larger catchments, improves the user-friendliness by avoiding conversion routines and allows the use of remotely sensed data. Processes incorporated in this model are rainfall, interception, surface storage in microdepressions, infiltration and vertical movement of water in the soil, overland flow, channel flow, detachment by rainfall and through-fall, detachment by overland flow and transport capacity of the flow. Special attention has been paid to the influence of tractor wheeling, small roads and surface sealing.

The study focuses on analyses of major development problems related to livelihood and natural resource management in the Northern Uplands of Vietnam (NUV). The study was conducted in Suoi Con, a small agro-forestry watershed with the total area is about 1760 ha. The watershed is characterized by a high poverty rate and low agricultural production and household income. Livelihood of the households is dependent upon self-sufficient agricultural production, which accounts for nearly 80% of the total production value. Traditional agricultural activities have led to various land degradation problems. The main objective of the study is to integrate modeling of (i) erosion assessment, (ii) land use optimization and (iii) land use decision making in order to improve the effectiveness and adoption of recommendations that contribute to the improved livelihood of farmers and sustainable natural resource management. This will be achieved through: (1) increasing understanding of the interactions between agro-ecological and socio-economic dynamics at watershed scale; (2) facilitating emergence of a common agreement on ecological sustainability, social equity and economically sound solutions; and (3) stimulating dialogues among various stakeholders to achieve a shared responsibility of the common resources. The biophysical and socioeconomic characteristics of the study area were explored through surveys, FAO’s land evaluation, literature review and stakeholder meetings. The Predict and Localize Erosion and Runoff (PLER) model and the Revised Universal Soil Loss Equation (RUSLE) were used to examine influences of land use on soil erosion at the watershed scale.Although agricultural land in the watershed has several limitations such as steep slopes, low soil fertility, high acidity and serious soil erosion, different soil types and the large variation topography and crop suitability create flexibility in farmers’ land use decisions. The Land Use Planning and Analysis System (LUPAS) was then applied to analyze feasibilities of alternative land use options. Based on land use scenarios, 4 main land use constraints in the regions were analyzed. Results of the analysis were finally discussed with stakeholders though Role Playing Game sections to find feasible land use solution and to develop policy recommendations. Results of the study showed that different actors in the watershed have different views on land use targets, objectives, constraints and decisions. The integrated modeling approach used in this study identified that traditional technology level appears to be a largest constraint that significantly holds back agricultural production of the region. Land area, capital and labour are also constraints but they only appear if agricultural technology is improved. Land fragmentation should be considered as an important factor because without any new agricultural technique, crop variety or external capital, land consolidation can significantly improve food production and income. Integration of individual tools described in this study represents a participatory approach for land use planning, in which problems in land use are explicitly defined and land use plans are developed and revised by stakeholders under their own social and economic conditions. Imperfections in given land use plans and possible solutions proposed by stakeholders provide policy makers with ideas to improve land use planning and to bridge the gaps between land use objectives of the government and of farmers. The integrated modelling approach developed and presented in this thesis can make use of individual research tools for describing agro-ecological and socio-economic dynamics and for developing land use policy. It has the potential to serve planners and policy makers to increase the likelihood of developing plans that will effectively increase farmer livelihood and improve resource conservation. This integrated modelling approach can incorporate different aspects of land use into land use planning and test hypotheses regarding the contributions of intended plans to general development targets. Furthermore, it can support bottom-up land use planning as it allows incorporation of different stakeholders in analysing existing problems, proposing solutions and developing land use plans. Therefore, it can increase the likelihood of adoption. This in turn will create the chances for achievement of targets of the government, researchers and farmers through effective implementation of the plans.

The study focuses on analyses of major development problems related to livelihood and natural resource management in the Northern Uplands of Vietnam (NUV). The study was conducted in Suoi Con, a small agro-forestry watershed with the total area is about 1760 ha. The watershed is characterized by a high poverty rate and low agricultural production and household income. Livelihood of the households is dependent upon self-sufficient agricultural production, which accounts for nearly 80% of the total production value. Traditional agricultural activities have led to various land degradation problems. The main objective of the study is to integrate modeling of (i) erosion assessment, (ii) land use optimization and (iii) land use decision making in order to improve the effectiveness and adoption of recommendations that contribute to the improved livelihood of farmers and sustainable natural resource management. This will be achieved through: (1) increasing understanding of the interactions between agro-ecological and socio-economic dynamics at watershed scale; (2) facilitating emergence of a common agreement on ecological sustainability, social equity and economically sound solutions; and (3) stimulating dialogues among various stakeholders to achieve a shared responsibility of the common resources. The biophysical and socioeconomic characteristics of the study area were explored through surveys, FAO’s land evaluation, literature review and stakeholder meetings. The Predict and Localize Erosion and Runoff (PLER) model and the Revised Universal Soil Loss Equation (RUSLE) were used to examine influences of land use on soil erosion at the watershed scale.Although agricultural land in the watershed has several limitations such as steep slopes, low soil fertility, high acidity and serious soil erosion, different soil types and the large variation topography and crop suitability create flexibility in farmers’ land use decisions. The Land Use Planning and Analysis System (LUPAS) was then applied to analyze feasibilities of alternative land use options. Based on land use scenarios, 4 main land use constraints in the regions were analyzed. Results of the analysis were finally discussed with stakeholders though Role Playing Game sections to find feasible land use solution and to develop policy recommendations. Results of the study showed that different actors in the watershed have different views on land use targets, objectives, constraints and decisions. The integrated modeling approach used in this study identified that traditional technology level appears to be a largest constraint that significantly holds back agricultural production of the region. Land area, capital and labour are also constraints but they only appear if agricultural technology is improved. Land fragmentation should be considered as an important factor because without any new agricultural technique, crop variety or external capital, land consolidation can significantly improve food production and income. Integration of individual tools described in this study represents a participatory approach for land use planning, in which problems in land use are explicitly defined and land use plans are developed and revised by stakeholders under their own social and economic conditions. Imperfections in given land use plans and possible solutions proposed by stakeholders provide policy makers with ideas to improve land use planning and to bridge the gaps between land use objectives of the government and of farmers. The integrated modelling approach developed and presented in this thesis can make use of individual research tools for describing agro-ecological and socio-economic dynamics and for developing land use policy. It has the potential to serve planners and policy makers to increase the likelihood of developing plans that will effectively increase farmer livelihood and improve resource conservation. This integrated modelling approach can incorporate different aspects of land use into land use planning and test hypotheses regarding the contributions of intended plans to general development targets. Furthermore, it can support bottom-up land use planning as it allows incorporation of different stakeholders in analysing existing problems, proposing solutions and developing land use plans. Therefore, it can increase the likelihood of adoption. This in turn will create the chances for achievement of targets of the government, researchers and farmers through effective implementation of the plans.

Dit rapport beschrijft een semi-quantitatieve module om concentraties in het oppervlaktewater te schatten uitgaande van verschillende routes. Het accent ligt op de bijdragen van de runoff (op of vlak onder het bodemoppervlak) en de erosie na zware regenbuien. Met behulp van deze module (in een spreadsheet) kunnen de potentiele bijdragen van zowel de runoff als de erosie worden ingeschat. De module schat geen actuele concentraties. De module is gebaseerd op twee complementaire processen: enerzijds worden hydrofobe pesticiden verondersteld het oppervlaktewater te kunnen bereiken door het transport van bodemdeeltjes, waaraan de pesticide is gesorbeerd ; anderzijds kunnen wateroplosbare pesticiden het aangrenzende oppervlaktewater bereiken met de waterstroom zelf, waarin het pesticide is opgelost, hetzij ter hoogte van of vlak onder het maaiveld. Deze semi-quantitatieve benadering heeft als voordelen een heldere structuur en een makkelijke toepasbaarheid. Bovendien biedt het een gestandaardiseerde manier om pesticiden te prioriteren op hun potentiele verspreidingsroutes. Dit rapport geeft de huidige praktijk wat betreft de toelating van pesticiden in Nederland niet weer.

Dit rapport beschrijft een semi-quantitatieve module om concentraties in het oppervlaktewater te schatten uitgaande van verschillende routes. Het accent ligt op de bijdragen van de runoff (op of vlak onder het bodemoppervlak) en de erosie na zware regenbuien. Met behulp van deze module (in een spreadsheet) kunnen de potentiele bijdragen van zowel de runoff als de erosie worden ingeschat. De module schat geen actuele concentraties. De module is gebaseerd op twee complementaire processen: enerzijds worden hydrofobe pesticiden verondersteld het oppervlaktewater te kunnen bereiken door het transport van bodemdeeltjes, waaraan de pesticide is gesorbeerd ; anderzijds kunnen wateroplosbare pesticiden het aangrenzende oppervlaktewater bereiken met de waterstroom zelf, waarin het pesticide is opgelost, hetzij ter hoogte van of vlak onder het maaiveld. Deze semi-quantitatieve benadering heeft als voordelen een heldere structuur en een makkelijke toepasbaarheid. Bovendien biedt het een gestandaardiseerde manier om pesticiden te prioriteren op hun potentiele verspreidingsroutes. Dit rapport geeft de huidige praktijk wat betreft de toelating van pesticiden in Nederland niet weer.

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

Achteruitgang van de kwaliteit van land voor landbouwproductie als gevolg van land degradatie kan een bedreiging vormen voor de voedselproductie. Erosie veroorzaakt door oppervlakkige afstroming van neerslag is wereldwijd de belangrijkste vorm van land degradatie, met irreversibele effecten. Dit rapport beschrijft het IMAGE land degradatie model waarmee huidige en toekomstige problemen van erosie door regenval kunnen worden beschreven met een ruimtelijke resolutie van 0.5 breedtegraad bij 0.5 lengtegraad. De gevoeligheid voor water erosie wordt berekend uit een aantal bodemhoedanigheden en relief, de intensiteit van regenval en de landbedekking. De relatieve gevoeligheid voor water erosie wordt uitgedrukt in een kwalitatieve index, omdat kwantificering van bodemverlies op de gewasproductiviteit van land op mondiale schaal niet mogelijk is. De resultaten kunnen worden gebruikt om gebieden te identificeren waar problemen van erosie op kunnen treden, op basis van scenario's van groeiende bevolking en economie, technologische vooruitgang en klimaatverandering.

This research looks at landscape dynamics – erosion and deposition – from two different perspectives: long-term landscape evolution over millennial timescales on the one hand and short-term event-based erosion and deposition at the other hand. For the first, landscape evolution models (LEMs) are often used, which describe landscape forming processes by geomorphic transport laws, usually on annual temporal resolutions. LEM LAPSUS is used in this research to evaluate the landscape dynamics in a study area in south-east Spain: the Guadalentín Basin. The model is calibrated on dated river terrace levels, which show an erosion – deposition – erosion sequence that the model could reproduce. Annual precipitation in this dryland area shows large inter-annual variability and erosion is supposed to be mainly the results of low-frequency, high magnitude rainfall events. Therefore, in this research, landscape dynamics are also assessed using the event-based erosion model OpenLISEM. Eventually, the role of extreme events in long-term landscape evolution are explored by comparing the two models and by incorporating annual rainfall variability into LEM LAPSUS. Another issue that is being addressed in this study is the relative influence of humans as compared to erosion as a natural process. A conceptual model, derived on the basis of dated sediment archives, is tentatively correlated to periods of human impact on the land. Using LAPSUS, the potential influence of historical tillage erosion is simulated, showing that the relatively slow process of tillage erosion added to floodplain aggradation over thousands of years.

Drempels tussen aardappelruggen zijn effectief tegen erosie. Dat blijkt uit onderzoek van PPO op praktijkbedrijven in Zuid-Limburg. Wanneer deze maatregel wordt erkend, zouden akkerbouwers op erosiegevoelige gronden de mogelijkheid om te ploegen toch kunnen behouden.