Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Winter hydrology and soil erosion processes in an agricultural catchment in Norway
    Starkloff, Torsten - \ 2017
    Wageningen University. Promotor(en): C.J. Ritsema, co-promotor(en): J. Stolte; R. Hessel. - Wageningen : Wageningen University - ISBN 9789463432207 - 154
    catchment hydrology - erosion - winter - snow - norway - hydrologie van stroomgebieden - erosie - winter - sneeuw - noorwegen

    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.

    Pesticide use and off-site risk assessment : a case study of glyphosate fate in Chinese Loess soil
    Yang, X. - \ 2016
    Wageningen University. Promotor(en): Coen Ritsema; Violette Geissen, co-promotor(en): Hans Mol; Fei Wang. - Wageningen : Wageningen University - ISBN 9789462576759 - 152
    pesticides - risk assessment - pesticide residues - glyphosate - loess soils - soil pollution - erosion - china - pesticiden - risicoschatting - pesticidenresiduen - glyfosaat - lössgronden - bodemverontreiniging - erosie - china

    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 (p<0.01), rather than by introduction labelled on pesticide package bag/bottle and media tools (TV/newspaper/Internet/books). Protective measures were inadequate and washing hands (>70%) 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<0.01) in runoff and suspended load, respectively. The transport rate of glyphosate (including AMPA) by runoff and suspended load was approximately 4% and 10% of the applied amount, respectively indicating that it mainly underlies particulate transport. The glyphosate and AMPA content in the flume soil at the end of the experiment (after 1h) decreased significantly with depth (p<0.05), and 72, 2, and 3% of the applied glyphosate (including AMPA) remained in the 0-2, 2-5, and 5-10 cm soil layers, respectively. Thus, the risk of leaching was low. In view of loss of 14 % of the initially applied glyphosate after 1 h, “buffer zone”, referred as the protection area for ecosystem discharge between farming land and public rivers, is strongly recommended, especially in regions where rain-induced soil erosion is common.

    3) Investigation of the on-site fate of glyphosate and AMPA formation in Chinese loess soil

    In this study, we observed glyphosate decay, erosion and runoff related transport of glyphosate and AMPA at different slopes (10° and 20°) and application rates (3.6 kg ha-1 and 7.2 kg ha-1) under field condition during 35 d, September-October in 2012 (16.8±2.1°C with 35 mm rainfall in total) and July-August in 2013 (27 ± 2.3°C with 74 mm rainfall in total). The initial glyphosate decayed rapidly (half-life of 3.5 d) in the upper 2 cm of soil following a first-order rate of decay. AMPA content in the 0-2 cm soil layer correspondingly peaked 3 d after glyphosate application and then gradually decreased. The residues of glyphosate and AMPA decreased significantly with soil depth (p<0.05) independently of the slope inclination and application rate. About 0.36% of the glyphosate initially applied was transported off-site plots after one erosive rain 2 days after the application. Glyphosate and AMPA concentration in runoff were low while the contents in the sediment was much higher than in the upper 2 cm of the soil. This suggested that even though the transported glyphosate is limited, the off-site risk of glyphosate and AMPA is high. Consequently, a realistic erosion-pesticide model should be developed that can simulate the particulate-facilitated transport of glyphosate and its off-site risks involving decay processes.

    4) Off-site risk assessment of particle-facilitated pesticide transport related to erosion

    In this study, we have developed a parsimonious integrative model of pesticide displacement by runoff and erosion that explicitly accounts for water infiltration, erosion, runoff, and pesticide transport and degradation in soil. The conceptual framework was based on broadly accepted assumptions such as the convection-dispersion equation and lognormal distributions of soil properties associated with transport, sorption, degradation, and erosion. To illustrate the concept, a few assumptions are made with regard to runoff in relatively flat agricultural fields: dispersion is ignored and erosion is modelled by a functional relationship. A sensitivity analysis indicated that the total mass of pesticide associated with soil eroded by water scouring increased with slope, rain intensity, and water field capacity of the soil. The mass of transported pesticide decreased as the micro-topography of the soil surface became more distinct. The timing of pesticide spraying and rate of degradation before erosion negatively affected the total amount of transported pesticide. The mechanisms involved in pesticide displacement, such as runoff, infiltration, soil erosion, and pesticide transport and decay in the topsoil, were all explicitly accounted for, so the mathematical complexity of their description can be high, depending on the situation.

    Overall, the outcome of this study indicates that it is urgent to improve farmers knowledge and awareness on pesticide use in order to reduce pesticide risks before they are applied in environmental system. The rapid decay of glyphosate to AMPA in loess soil suggests that on-site risks of glyphosate is mainly related to AMPA, especially under warmer climatic conditions. The off-site transport of glyphosate in our study was about 14% of the applied dose after 1 h of rainfall indicating that the off-site risks of glyphosate should be taken into account in regions highly prone to soil erosion. The concept of particulate transport elaborated in objective 4 should be incorporated in existing erosion models, such as LISEM, to predict off-site effects of glyphosate applications.

    Roaming livestock distribution, densities and population estimates for St. Eustatius, 2013
    Debrot, A.O. ; Hazenbosch, J.C.J. ; Piontek, S. ; Kraft, C. ; Belle, J. van; Strijkstra, A. - \ 2015
    Den Helder : IMARES (Report / IMARES Wageningen UR C088/15) - 27
    sint eustatius - vee - wilde dieren - populatiedichtheid - herkauwers - erosie - caribische eilanden - milieuafbraak - sint eustatius - livestock - wild animals - population density - ruminants - erosion - caribbean islands - environmental degradation
    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.
    Integrated modelling for land use planning and policy recommendation in the Northern Uplands of Vietnam
    Bui, T.Y. - \ 2013
    Wageningen University. Promotor(en): Leo Stroosnijder, co-promotor(en): Saskia Visser. - S.l. : s.n. - ISBN 9789461736406 - 102
    landgebruiksplanning - landgebruik - modelleren - beleid - hulpbronnenbeheer - natuurlijke hulpbronnen - erosie - landbouwproductie - vietnam - land use planning - land use - modeling - policy - resource management - natural resources - erosion - agricultural production - vietnam

    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.

    Mind the gap! Het verschil in tijdschaal tussen extreme regenbuien en landschapsevolutie
    Baartman, J.E.M. - \ 2012
    Bodem 22 (2012)5. - ISSN 0925-1650 - p. 27 - 29.
    erosie - watererosie - geomorfologie - hellingen - modellen - erosion - water erosion - geomorphology - slopes - models
    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!
    Quick Scan Monitoring Delta Programme Wadden Sea Area
    Stapel, J. ; Dankers, N.M.J.A. - \ 2012
    IMARES : IMARES (Report / IMARES Wageningen UR C074/12) - 25
    hydrodynamica - geologische sedimentatie - geomorfologie - erosie - zandsuppletie - projecten - informatiediensten - monitoring - wadden - hydrodynamics - geological sedimentation - geomorphology - erosion - sand suppletion - projects - information services - monitoring - tidal flats
    Welke informatie is bekend over: veiligheid, natuur en sociaaleconomische ontwikkeling in het Delta Programma Waddengebied. Naar aanleiding van deze Quickscan worden de volgende vijf monitoringstaken voorgesteld die grotendeels parallel kunnen worden uitgevoerd. Een aantal taken kunnen gefaseerd worden uitgevoerd: • Organisatie: Overzicht en analyse van monitoringbehoefte, Opzetten klimaat monitoring netwerk en harmonisatie en Data Management (gefaseerd) • Trend Analyse van historische ecologische en sociaaleconomische datasets• Hydrodynamische en geomorfologische monitoring in kombergingsgebieden en model ontwikkeling (gefaseerd) • Quick Reaction Force (gefaseerd): Organisatie en protocolontwikkeling, apparatuuraanschaf en -kalibratie en registratie van erosie onmiddellijk na stormperiodes en hersteltijd (semi-natuurlijke flexibiliteit onder invloed van zandsuppletie) • Monitoring van sociaaleconomische en governance ontwikkelingen en projectvoortgang
    Risk assessment methodologies of soil threats in Europe: status and options for harmonization for risks by erosion, compaction, salinization, organic matter decline and landslides
    Ano-Vidal, C. ; Ehlert, P.A.I. ; Hagyo, A. ; Heesmans, H.I.M. ; Kuikman, P.J. ; Oenema, O. ; Recatala-Boix, L. ; Simota, C. ; Tóth, G. ; Beek van, C. ; Akker van de, J. ; Zee, S.E.A.T.M. van der; Verzandvoort, S. - \ 2012
    Luxembourg : Publications Office of the European Union (JCR scientific and technical reports ) - ISBN 9789279142918 - 84
    risicoschatting - methodologie - bodemdegradatie - erosie - bodemverdichting - verzilting - organisch bodemmateriaal - aardverschuivingen - europa - risk assessment - methodology - soil degradation - erosion - soil compaction - salinization - soil organic matter - landslides - europe
    The EU thematic strategy for soil protection recognizes that soil degradation through erosion, soil organic matter decline, compaction, salinization and landslides occurs in specific areas, and that these areas must be identified in an unequivocal way. Currently, there are various risk assessment methodologies (RAMs) and the question has risen to what extent these RAMs yield similar outcome and, if not, whether the outcome can be harmonized, i.e. whether the results of the various RAMs can be made compatible or comparable. In this study i) the current status of RAMs for erosion, soil organic matter decline, compaction, and salinization in the European Union (EU27) is reviewed, and ii) the need and the options for harmonization are assessed. The need for harmonization was defined as the likelihood of achieving different outcomes when using different RAMs, whereas the options for harmonization refer to the efforts that are required to harmonize soil RAMs. The current status of RAMSs in EU-27 was assessed on the basis of questionnaires, which were sent out to soil specialists and policy officers in all Member States. We received more than 100 (response rate >50%) completed questionnaires. It turned out that many of the so called RAMs are still incomplete; they are ‘process (or threat) quantifications’ rather than methodologies that assess the risk of a soil threat. Moreover, there were significant differences between RAMs for a soil threat in terms of (i) the notion of the threat, (ii) data collection, (iii) data processing, (iv) data interpretation, and (v) risk perception. The need for harmonization appeared highest for erosion and salinization, whereas the options for harmonization were best for SOM decline. Harmonization of soil RAMs may be very complex and for that reason not always feasible. We suggest two options that may facilitate unequivocal identification of risk (or priority) areas for soil threats, i) a two Tiered approach based on data availability and spatial scale and ii) generic harmonization, i.e. combining standardization and harmonization in a rather pragmatic way
    Mind the gap: modelling event-based and millennial-scale landscape dynamics
    Baartman, J.E.M. - \ 2012
    Wageningen University. Promotor(en): Tom Veldkamp; Coen Ritsema, co-promotor(en): Jeroen Schoorl. - S.l. : s.n. - ISBN 9789461732668 - 216
    geomorfologie - erosie - sedimentatie - dynamica - tijdschalen - landschapsanalyse - modelleren - rivieren - regen - menselijke invloed - landschap - ontwikkeling - spanje - pleistoceen - holoceen - geomorphology - erosion - sedimentation - dynamics - time scales - landscape analysis - modeling - rivers - rain - human impact - landscape - development - spain - pleistocene - holocene

    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.

    Drempel tussen ruggen werkt goed tegen erosie : PPO pleit voor erkenning drempels als erosie-maatregel
    Meuffels, G.J.H.M. - \ 2012
    Akker magazine 2012 (2012)4. - ISSN 1875-9688 - p. 17 - 17.
    aanaarden tot ruggen met dwarsruggetjes - ruggen - akkerbouw - erosie - erosiebestrijding - aardappelen - grondbewerking - zuid-limburg - tie ridging - ridges - arable farming - erosion - erosion control - potatoes - tillage - zuid-limburg
    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.
    Sediment transport capacity for soil erosion modelling at hillslope scale: an experimental approach
    Ali, M. - \ 2012
    Wageningen University. Promotor(en): Leo Stroosnijder, co-promotor(en): Geert Sterk; Manuel Seeger. - S.l. : s.n. - ISBN 9789461731319 - 119
    geologische sedimentatie - sediment - afvoer - erosie - stroming - modelleren - geological sedimentation - sediment - discharge - erosion - flow - modeling

    Soil erosion is a common global problem that has negative impacts on agriculture production, water storage facilities, water conveyance system, and water quality. To assess water erosion problems in catchments, scientists have developed several spatially distributed soil erosion models with various degree of sophistication. Examples are CREAMS, KYERMO, PRORILL, KINEROS2, LISEM, RUSLE, EUROSEM, EGEM, GLEAMS, and WEPP. Precise estimation of mean flow velocity and sediment transport capacity play a vital role in the accuracy of the outcomes of each spatially distributed soil erosion model. Worldwide, Manning and Darcy-Weisbach formulae are commonly used for the quantification of mean flow velocity in shallow overland flows, which were actually derived for stream flow. Likewise, majority of the functions used for sediment transport estimation were originally derived for channel flow. The applicability of stream flow functions has become questionable under overland flow, because the water layer depths and discharges are usually much smaller in overland flow. Moreover, hillslope surfaces are usually rougher than streams. Hence, the main aims of this study were (i) How suitable are the existing approaches and functions that are used for mean flow velocity and sediment transport capacity quantification under overland flow conditions? (ii) Which hydrological and morphological factors affect and control the mean flow velocity and sediment transport capacity? (iii) What are optimal functions for the quantification of mean flow velocity and sediment transport capacity? To address all the research objectives of this study, it was necessary to precisely measure the hydraulic and sediment parameters under overland flow conditions, which was accomplished by conducting flume experiments under controlled conditions. Experiments were carried out in a 3.0 m long and 0.5 m wide rectangular hydraulic flume. Four non-cohesive, narrowly graded, commercially available sands with median grain diameter equal to 0.233, 0.536, 0.719, and 1.022 mm were selected for study of the variation in mean flow velocity and sediment transport capacity with grain size. In order to analyze the impact of slope and flow discharge on mean flow velocity and sediment transport capacity, the flume was inclined at four slope gradients (5.2, 8.7, 13.2 and 17.6%) and applied inflow discharges ranged from 33 to 1033 x 10-6 m3 s-1. To study the impact of the bed geometry on mean flow velocity and also the variation in bed form evolution with grain size, the flume bed was scanned before and after a run with a profile laser scanner. The performance of the five existing sediment transport capacity functions was evaluated for overland flow conditions using graphical and statistical analysis. The results show that the application of these functions is limited to the range of hydraulic and sediment conditions for which each was formulated. Regression analysis was carried out to examine the impact of different hydraulic and sediment parameters i.e. flow discharge, slope gradient, and median grain size on mean flow velocity and sediment transport capacity. The main aim of the regression analysis was to better understand the processes entailed in flow velocity and sediment transport. In view of the strong impact of flow discharge and median grain size on mean flow velocity, an empirical equation was derived for the estimation of mean flow velocity that was calibrated with five literature datasets. In-addition to this, the results of this study exhibit that unit stream power is an optimal composite force predictor for estimating transport capacity. Based on the unit stream power concept, a new physically based transport capacity function was derived by dimensional analysis using the experimental results. The newly derived function was calibrated using the flume experiment results, but validation is still needed for cohesive soils.

    Fire effects on soil and hydrology
    Stoof, C.R. - \ 2011
    Wageningen University. Promotor(en): Coen Ritsema; A.J.D. Ferreira. - S.l. : s.n. - ISBN 9789085859154 - 182
    brandgevolgen - branden - bodem - hydrologie - grondverwarming - as - fysische bodemeigenschappen - bodemwaterretentie - bodemtemperatuur - landdegradatie - erosie - fire effects - fires - soil - hydrology - soil heating - ash - soil physical properties - soil water retention - soil temperature - land degradation - erosion

    Fire can significantly increase a landscape’s vulnerability to flooding and erosion events. By removing vegetation, changing soil properties and inducing soil water repellency, fire can increase the risk and erosivity of overland flow. Mitigation of land degradation and flooding events after fire can help safeguard natural resources and prevent further economical and ecological havoc, but can benefit from an improved understanding of its drivers.
    The aim of this thesis is to improve the understanding of the effects of fire on soil and hydrology. Laboratory and field studies focus on the relation between fire, soil, vegetation and hydrology as well as the effects of scale, in order to find the drivers of post-fire flooding and erosion events. The effect of soil heating on soil physical properties is evaluated, and the above- and belowground drivers of soil heating are investigated. Furthermore, the results of a unique field experiment are presented in which the Portuguese Valtorto catchment was burned by experimental fire. The effects of fire on soil and surface properties is assessed, as well as the changes in the temporal evolution of soil water repellency, Finally, the hydrological implications are discussed. The thesis concludes with recommendations for mitigation of fire-induced land degradation; focusing on guidelines for prescribed burns, that are used to prevent fire, and on reducing runoff and erosion in burned lands where fire prevention was unsuccessful.

    Farmers, institutions and land conservation : institutional economic analysis of bench terraces in the highlands of Rwanda
    Bizoza Runezerwa, A. - \ 2011
    Wageningen University. Promotor(en): Erwin Bulte, co-promotor(en): Paul Hebinck. - S.l. : s.n. - ISBN 9789085859307 - 123
    ontwikkelingseconomie - boeren - institutionele economie - instellingen - landbouwgrond - bodembescherming - waterbescherming - erosie - terrassen - rwanda - oost-afrika - minst ontwikkelde landen - development economics - farmers - institutional economics - institutions - agricultural land - soil conservation - water conservation - erosion - terraces - rwanda - east africa - least developed countries
    Wijnandsrade werpt drempels op tegen erosie : Proefboerderij in Zuid-Limburgs heuvellandschap : Interview met Gerard Meuffels
    Buning, Stefan ; Meuffels, G.J.H.M. - \ 2011
    Akker magazine (2011)5. - ISSN 1875-9688 - p. 50 - 53.
    erosiebestrijding - erosie - proefboerderijen - akkerbouw - lössgronden - zuid-limburg - landbouwkundig onderzoek - erosion control - erosion - experimental farms - arable farming - loess soils - zuid-limburg - agricultural research
    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.
    Oesterriffen stoppen erosie van zandplaten in de Oosterschelde
    Imares, - \ 2010
    [S.l.] : YouTube
    oesters - schaaldieren - oosterschelde - biodiversiteit - waterwerken - duurzaamheid (sustainability) - erosie - natuurbescherming - oysters - shellfish - eastern scheldt - biodiversity - hydrographic structures - sustainability - erosion - nature conservation
    Kunnen riffen van oesters weerstand bieden aan de voortgaande erosie van zandplaten in de Oosterschelde? Met die vraag is IMARES, onderdeel van Wageningen UR, samen met het NIOO gestart met het aanbrengen van experimentele oesterriffen. De proef met banken van schelpdieren die de golfslag intomen en sediment invangen wordt uitgevoerd in het kader van het innovatieprogramma Building with Nature van de stichting Ecoshape, in samenwerking met Rijkswaterstaat, en moet behalve de dijken, ook de biodiversiteit op slikken en platen veilig stellen.
    Basismateriaal voor eventuele prioritaire gebieden : quick scan voor Drenthe
    Bakker, G. ; Hack-ten Broeke, M.J.D. ; Vries, F. de; Akker, J.J.H. van den - \ 2010
    Wageningen : Alterra (Alterra-rapport 1964) - 88
    erosie - bodem - organisch bodemmateriaal - bodemverdichting - nederland - kaderrichtlijn bodem - bodemkwaliteit - drenthe - erosion - soil - soil organic matter - soil compaction - netherlands - soil framework directive - soil quality - drenthe
    In vervolg op een studie die op nationale schaal inzicht gaf in het mogelijke voorkomen van bodembedreigingen waardoor in het kader van de concept Kaderrichtlijn Bodem prioritaire gebieden aangewezen moesten worden, is in dit rapport de aandacht gericht op de provincie Drenthe. Zowel in Nederland als in Drenthe zijn drie bodembedreigingen het meest relevant, namelijk erosie, afname van de hoeveelheid organische stof en verdichting. Bij erosie gaat het in de provincie Drenthe vooral over winderosie. Afname van de organische stofhoeveelheden speelt vooral in (voormalige) veengebieden.
    Seizoensverloop in de doorworteling van dijkgrasland – VTV-toetsing buiten het winterseizoen nader bekeken
    Schaffers, A.P. ; Frissel, J.Y. ; Adrichem, M.H.C. van; Huiskes, H.P.J. - \ 2010
    Wageningen : Alterra (Alterra-rapport 2014) - 60
    graslanden - dijken - beworteling - erosiegevoeligheid - erosie - vegetatie - seizoenen - veiligheid - nederland - grasslands - dykes - rooting - erodibility - erosion - vegetation - seasons - safety - netherlands
    Dit rapport geeft de bevindingen weer van een studie naar het seizoensverloop in de doorworteling van dijkgrasland. Het seizoen blijkt van invloed te zijn op de doorworteling van de zode van dijkgrasland zoals die met de gangbare handmethode in het veld wordt vastgesteld ten behoeve van de wettelijk verplichte toetsing volgens het Voorschrift Toetsen op Veiligheid (VTV).
    Kaderrichtlijn bodem : basismateriaal voor eventuele prioritaire gebieden
    Hack-ten Broeke, M.J.D. ; Beek, C.L. ; Hoogland, T. ; Knotters, M. ; Mol-Dijkstra, J.P. ; Schils, R.L.M. ; Smit, A. ; Vries, F. de - \ 2009
    Wageningen : Alterra (Alterra-rapport 2007) - 77
    organisch bodemmateriaal - bodemverdichting - bodembeleid - erosie - nederland - europa - kaderrichtlijn bodem - soil organic matter - soil compaction - soil conservation policy - erosion - netherlands - europe - soil framework directive
    Dit rapport geeft een overzicht van het basismateriaal voor de bodembedreigingen die genoemd worden in de ontwerpteksten voor de Kaderrichtlijn Bodem (KRB) en waarbij wordt gesproken over de aanwijzing van prioritaire gebieden. Waar mogelijk bestaat dit materiaal uit kaarten voor Europa en Nederland. Achtereenvolgens komen de thema’s erosie, organische stof, verdichting, verzilting en verzuring aan bod. Voor Nederland zijn de eerste drie thema’s waarschijnlijk het meest aan de orde. Voor erosie gaat het dan naast watererosie, dat slechts in een beperkt deel van het land voorkomt, vooral over winderosie. Afname van de hoeveelheid organische stof is vooral aan de orde in de veengebieden van ons land. Verdichting lijkt op veel plaatsen een probleem te gaan vormen, maar hierover is nog veel onzekerheid. Verzilting, verzuring en aardverschuivingen zijn in de ontwerpteksten van de KRB zo gedefinieerd dat ze in Nederland niet aan de orde zijn. In het rapport wordt ook ingegaan op de gegevensbehoefte
    Vegetatiekundige inventarisatie en erosiebestendigheid van de waterkeringen in het beheersgebied van Waterschap Vallei en Eem
    Schaffers, A.P. ; Huiskes, H.P.J. - \ 2009
    Wageningen : Alterra (Alterra-rapport 1885) - 136
    vegetatie - karteringen - inventarisaties - planten - graslanden - erosiegevoeligheid - dijken - erosie - waterschappen - natuurbeheer - gelderland - utrecht - vegetation - surveys - inventories - plants - grasslands - erodibility - dykes - erosion - polder boards - nature management - gelderland - utrecht
    Dit rapport verwoordt de bevindingen van het onderzoek naar vegetatiekundige samensteling en erosiebestendigheid van de graslanden op kades en dijken in het werkgebied van waterschap Vallei en Eem. De erosiebestendigheid van de grasmat is beschreven aan de hand van het voorschrift toetsen op veiligheid 2006 (VTV 2006). De overige kades zijn beschreven vanuit een vegetatiekundig oogpunt met aandacht voor beheerproblematiek als ruigte soorten en graslandproductie. De beheerder wordt per kadevak geadviseerd over het behoud van de actuele natuurwaarde, interessante soorten, lokale problemen als open plekken en de mogelijkheden voor verbetering van de vegetatie ter plekke. Ook wordt een voorstel gedaan hoe de monitoring van de natuurwaarde en kwaliteit van graslanden op waterkeringen vorm te geven in. Voor de waterkeringen in het noorden van het beheergebied van het waterschap wordt een advies geven hoe om te gaan met actuele natuur waarden bij de aanstaande reconstructie van deze dijkvakken
    Sustainable Land Management in the Tropics : Explaining the Miracle
    Burger, C.P.J. ; Zaal, F. - \ 2009
    Farnham, England : Ashgate (International Land Management Series ) - ISBN 9780754644552 - 226
    grondbeheer - klimaatverandering - erosie - tropen - bodembescherming - waterbescherming - afrika ten zuiden van de sahara - plattelandsontwikkeling - landgebruik - ontwikkelingseconomie - duurzame ontwikkeling - economische aspecten - land management - climatic change - erosion - tropics - soil conservation - water conservation - africa south of sahara - rural development - land use - development economics - sustainable development - economic aspects
    Bringing together case studies from Kenya, Benin, Cameroon and the Philippines, this volume provides a multidisciplinary overview of the economics of natural resource management in Tropical regions, at household and village level. By comparing a wide array of climatic and economic conditions, it examines the effect of location and access to the market - as well as the importance of national policies - have on soil and water conservation. The book not only analyzes the benefits of soil and water conservation based on econometric studies, but also assesses the costs involved. In doing so it challenges commonly held assumptions about poorer community's ability to finance such measures.
    Soil - The living skin of planet earth.
    Hartemink, A.E. ; Nortcliff, S. ; Dent, D.L. - \ 2008
    Wageningen : ISRIC - World Soil Information/IUSS
    bodem - erosie - bodembescherming - soil - erosion - soil conservation
    Soils are vulnerable. The largest disruption and destruction is caused by humans. It is not a new phenomenon as soil degradation took place in the early civilisations in the basin of the Tigris and Euphrates. A major threat is soil erosion by which the soil is removed often exposing unweathered rock. Soil erosion arises from poor land management activities, for example cultivating steeply sloping land
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