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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    Klassenindelingen voor de fosfaattoestand van de bodem, ten behoeve van de afleiding van fosfaatgebruiksnormen
    Oenema, O. ; Mol, J.P. ; Voogd, J.C.H. ; Ehlert, P.A.I. ; Velthof, G.L. - \ 2016
    Wageningen : Alterra, Wageningen-UR (Alterra-rapport 2743) - 39
    bodem - fosfaten - graslanden - bouwland - akkergronden - graslandgronden - soil - phosphates - grasslands - arable land - arable soils - grassland soils
    In 2006 is het stelsel van gebruiksnormen voor stikstof en fosfaat ingevoerd in de Nederlandse landbouw om de uit- en afspoeling van stikstof en fosfaat vanuit de landbouw naar grondwater en oppervlaktewater te verminderen. In 2010 zijn de gebruiksnormen voor fosfaat gedifferentieerd naar de fosfaattoestand van de bodem. Daarbij worden vier klassen voor de fosfaattoestand van de bodem onderscheiden, namelijk arm, laag, neutraal en hoog. De grenzen tussen de klassen worden bepaald via een bepaling van het Pw-getal (voor bouwland) en het P-AL-getal (voor grasland). In 2015 heeft de Commissie Deskundigen Meststoffenwet (CDM) voorgesteld om de fosfaattoestand te bepalen op basis van een gecombineerde indicator, namelijk P-CaCl2 en het P-AL-getal, omdat een gecombineerde indicator in theorie een betere voorspelling geeft van de fosfaattoestand, en de gecombineerde indicator reeds in de praktijk en voor de bemestingsadviezen van grasland en maisland wordt toegepast. Ook speelt een rol dat het Pw-getal door verschillende analyselaboratoria niet meer wordt bepaald. In onderhavig rapport worden voor de gecombineerde indicator klassengrenzen afgeleid voor de fosfaattoestand van de bodem. Daarbij is gebruikgemaakt van een grote database (ruim 55.000 monsters) en van statistische analyses om een klassenindeling gebaseerd op het Pw-getal voor bouwland en op het P-AL-getal voor grasland om te rekenen naar een klassenindeling voor de gecombineerde indicator P-CaCl2 en het P-AL-getal. Verschillende varianten zijn voorgesteld. Effecten van de varianten op fosfaatplaatsingsruimte zijn verkend.
    Bodemkwaliteit op veengrond : effecten van drie maatregelen op een rij
    Eekeren, N.J.M. van; Deru, Joachim ; Lenssinck, F.A.J. ; Bloem, J. - \ 2016
    Driebergen : Louis Bolk Instituut - 32
    biologische landbouw - bodemkwaliteit - veengronden - graslandgronden - melkveehouderij - organic farming - soil quality - peat soils - grassland soils - dairy farming
    Deze brochure behandelt de bodemkwaliteit van veengrond. In Hoofdstuk 2 worden de zes elementen van bodemkwaliteit besproken. Hoofdstuk 3 gaat over meten en beoordelen van bodemkwaliteit. In Hoofdstuk 4 worden drie praktijkmaatregelen in het veenweidegebied behandeld. Onderdeel van deze brochure is een checklist voor bodemkwaliteit die elke melkveehouder op veen kan doorlopen.
    Vegetatie-, beheer- en habitattypen van Het Nationale Park De Hoge Veluwe in 2014
    Bijlsma, R.J. ; Janssen, J.A.M. ; Weeda, E.J. ; Griffioen, A.J. - \ 2015
    Wageningen : Alterra, Wageningen-UR (Alterra-rapport 2616)
    vegetatiemonitoring - habitats - vegetatietypen - nationale parken - heidegebieden - eolisch zand - graslandgronden - natuurgebieden - inventarisaties - veluwe - vegetation monitoring - habitats - vegetation types - national parks - heathlands - aeolian sands - grassland soils - natural areas - inventories - veluwe
    In 2014 is een vegetatiekartering uitgevoerd van Het Nationale Park De Hoge Veluwe uitgaande van een luchtfoto-interpretatie uit 2013 en kleurenfoto’s uit 2010. Het Park bestaat voor ruim 30% uit Natura 2000-habitattypen, verdeeld over 12 typen en draagt belangrijk bij aan oppervlakten habitattype van de Veluwe, met name voor Zandverstuivingen (848 ha), Stuifzandheiden (270 ha), Zure vennen en Heideveentjes (16 ha), Vochtige heiden (27 ha), Heischrale graslanden (189 ha) en Oude eikenbossen (240 ha). Ten opzichte van de kartering in 2007 zijn er op hoofdlijnen de volgende ontwikkelingen: de oppervlakte zandverstuivingen is met maximaal 10% afgenomen, vooral door successie naar Stuifzandheiden; Stuifzandheiden zijn afgenomen ten gunste van Droge heiden; de oppervlakte Heischrale graslanden is praktisch gelijk gebleven; vergrassing met Pijpenstrootje is voortgeschreden; de oppervlakten Vochtige heiden en Zure vennen zijn niet wezenlijk veranderd; habitattype Zwakgebufferde vennen is nieuw onderscheiden met een zeer klein oppervlakte; de oppervlakte Heideveentjes is toegenomen door betere inventarisatie; Jeneverbesstruwelen en Oude eikenbossen zijn in oppervlakte gelijk gebleven; het weinig voorkomende type Beuken-eikenbossen met hulst is uitgebreid met een deel dat in 2007 ten onrechte niet was onderscheiden. De vegetatietypen zijn toegekend aan 11 natuurbeheertypen waarvan N16.01 Droog bos met productie 48% van de oppervlakte inneemt, gevolgd door N01.01 Droge heide met 22% en N07.02 Zandverstuiving met 14%. De overige typen beslaan elk minder dan 5% van de oppervlakte. Vooralsnog is alleen het landschapsbeheertype L01.07 Lanen onderscheiden.
    Strategisch stikstof bemesten op melkbeebedrijven : welke bemestingsadvies gebruik je als stikstof knelt?
    Curth-van Middelkoop, J.C. - \ 2015
    melkveebedrijven - stikstof - dierlijke meststoffen - consultancy - graslandgronden - maïs - bemesting - dairy farms - nitrogen - animal manures - consultancy - grassland soils - maize - fertilizer application
    Dit is een flyer met bemestingsadvies met betrekking tot stikstof. Gebruiksnormen voor stikstof (N) zijn voor gras en snijmaïs lager dan N-bemestingsadvies, met name op zand en löss. Normen gelden op bedrijfsniveau, u heeft de verdeling van de N in eigen hand over: Gewassen; (Groepen van) Percelen en eventueel grondsoorten; Tijd in het uitrijseizoen.
    Innovatieve maïsteelt op veengrond in Noord-Holland : jaarrapportage 2012
    Schooten, H.A. van; Deru, J.G.C. ; Parmentier, F. - \ 2013
    Lelystad : Wageningen UR Livestock Research - 16
    zea mays - strokenteelt - graslanden - graslandgronden - veengronden - bodemdaling - grondbewerking - drainage - grondwaterstand - melkveehouderij - noord-holland - zea mays - strip cropping - grasslands - grassland soils - peat soils - subsidence - tillage - drainage - groundwater level - dairy farming - noord-holland
    In de proef op veengrond in Noord Holland is het effect op het grondwaterpeil onderzocht van maïs versus grasland, waarbij de maïs met de strokenfrees is ingezaaid of traditioneel (spitten), zowel ongedraineerd als met onderwaterdrainage. Ook opbrengsten en opbrengstkwaliteit zijn gemeten. De resultaten van het eerste jaar (2012) - waarbij het een heel nat jaar betrof - laten zien dat het grondwaterpeil bij maïs hoger blijft dan bij grasland, en dat het peil onder maïs in stroken hoger is dan bij spitten. Samen met het feit dat bij strokenfrezen ca. 90% van de bouwvoor ongestoord blijft, wordt verondersteld dat het effect van maïsteelt in stroken op bodemdaling gering is. Spitten gaf duidelijk hogere opbrengsten dan strokenteelt, en drainage had een grote positieve invloed op de opbrengst zowel bij spitten als bij strokenteelt. De oogst verliep met duidelijk minder structuurschade bij de strokenfrees ten opzichte van spitten.
    Direct zaaien van maïs in bestaande zode
    Schrauwen, R. ; Eekeren, N.J.M. van - \ 2011
    Royal Haskoning [etc.]
    teeltsystemen - maïs - direct zaaien - rijenbemesting - graslandgronden - zaaien - bemesting - cropping systems - maize - direct sowing - band placement - grassland soils - sowing - fertilizer application
    Met de techniek direct zaaien van maïs wordt maïs in doodgespoten bestaand grasland of groenbemester ingezaaid zonder te ploegen, maar door smalle banen te frezen van 12 cm. Tegelijkertijd wordt de drijfmest in de gefreesde rij toegediend.
    Chemical characterization of manure in relation to manure quality as a contribution to a reduced nitrogen emission to the environment
    Stelt, B. van der - \ 2007
    Wageningen University. Promotor(en): Willem van Riemsdijk, co-promotor(en): Erwin Temminghoff. - [S.l.] : S.n. - ISBN 9789085046301 - 152
    dierlijke meststoffen - ammoniak - vervluchtiging - dieet - stikstofkringloop - graslandgronden - organisch bodemmateriaal - samenstelling - voer - animal manures - ammonia - volatilization - diet - nitrogen cycle - grassland soils - soil organic matter - composition - feeds
    Keywords:manure composition, ammonia volatilization, free ions, Donnan Membrane Technique, manure additives, dietary changes, nitrogen dynamics,grasslandsoils.

    More insight in manure composition, ammonia (NH 3 ) volatilization, and into relationships between soil organic matter (SOM) content and nitrogen (N) flows in grasslands is needed to improve the nutrient use efficiency of manure as fertilizer for plants and concomitantly to reduce the environmental impact of agricultural activities.

    Additives are often added to improve manure quality ( e.g. reduce NH 3 volatilization). Laboratory studies showed that additives used in this study did in general not affect manure characteristics or NH 3 volatilization, when manure was incubated at three temperatures and either regular mixed or not mixed. Only when Agri-mest ® and Effective Micro-organisms ® were both added and the manure was incubated at 4 °C without mixing, NH 3 volatilization was reduced by 34%.

    To study manure composition in more detail, a DMT-manure cell was developed, which either measures 'free' dissolved cation or anion concentrations in manure. Dilution studies showed that total nutrient concentrations and monovalent 'free' dissolved cation concentrations decreased proportionately with increasing dilution, whereas 'free' dissolved divalent cation concentrations were buffered upon dilution. The buffering of divalent cation concentrations is probably the result of the release of these ions from organic matter, or it is the result of the dissolution of certain phosphate minerals ( e.g. struvite and whitlockite). Only a small part of the total phosphorus (P) content (<1%) and the total sulphur content (<13%) was present in a 'free' dissolved ionic form.

    A feeding trial with non-lactating cows showed that the total N and P content and the total ammoniacal nitrogen (TAN= NH 3,aq + NH 4+ ) content of manure increased when the dietary protein or energy content was raised, whereas the 'free'-to-total ratios of Ca and Mg in the manures were not affected by dietary changes. Ammoniavolatilization from manure increased with an increase in dietary protein content and decreased with an increase in dietary energy content, although the TAN content of manures produced from diets with a higher dietary energy content werehigher.

    A field trial, in combination with incubation studies, was carried out in the VEL-VANLA area to study how N dynamics was affected by SOM content. Incubation studies showed that potential N mineralization rates (measured at 20 °C and 60% water holding capacity) of eighteen grassland soils were related to the initial dissolved organic nitrogen content and to the dissolved organic carbon content of the soil, as measured in 0.01M CaCl 2 extracts. During the growing season, two peaks in total soluble N content were observed, which could not be related to the time of manure application, but were both preceded by a period of draught. Maximum total soluble N and nitrate content were higher in soils with a lower SOM content. This is probably caused by faster water depletion of soils with a lower SOM content during drought periods, which will hamper N uptake by plants.

    Concluding, adjusting diets seems to be a more promising way to reduce NH 3 volatilization than the use of manure additives, especially since adjusting the diet will reduce NH 3 volatilization at any time of manure handling (housing, storage, and during manure application), which is not always the case for other NH 3 volatilization reduction techniques. A proper estimation of N mineralization during the growing season can help to improve the nutrient gift (via manure) in order for plants to grow with limited risks to the environment. Dissolved organic N might be a promising parameter to estimate N mineralization.

    Precise soil management as a tool to reduce CH4 and N2O emissions from agricultural soil. III. A preliminary study on grassland soils
    Mosquera, J. ; Huis in 't Veld, J.W.H. ; Beek, C. ter; Hol, J.M.G. - \ 2005
    Wageningen : Agrotechnology & Food Innovations (Rapport / Wageningen UR, Agrotechnology & Food Innovations 569) - ISBN 9789067549868 - 17
    bodemverdichting - broeikasgassen - emissie - grondbewerking - graslandgronden - methaan - distikstofmonoxide - hulpbronnenbeheer - soil compaction - greenhouse gases - emission - tillage - grassland soils - methane - nitrous oxide - resource management
    Some environmental aspects of grassland cultivation; the effects of ploughing depth, grassland age, and nitrogen demand of subsequent crops
    Velthof, G.L. ; Meer, H.G. van der; Aarts, H.F.M. - \ 2002
    Wageningen : Alterra (Alterra-rapport 581) - 27
    graslanden - graslandbeheer - graslandgronden - milieu - milieufactoren - ploegen als grondbewerking - stikstof - akkerbouw - bodemvruchtbaarheid - grasland - grondbewerking - landbouw - nitraatuitspoeling - nutriënten - stikstofmineralisatie - weidebouw - grasslands - grassland management - grassland soils - environment - environmental factors - ploughing - nitrogen
    The Netherlands has submitted a derogation under the Nitrate Directives to the European Union (EU) in 2000. In the final opinion by a group of experts about the Dutch derogation, recommendations on ploughing of grasslands were included dealing with i) the depth of ploughing of permanent grassland, ii) the age of temporary grassland and iii) the nitrogen demand of the subsequent crop of temporary grassland. A literature study was carried out in order to provide scientific information on these three issues. No studies were found in literature in which the effects of cultivation depth on nitrogen mineralisation and losses in reseeded grassland were assessed. The results of transformation of grassland into arable land show no clear effects of ploughing depth on N mineralisation. Differences in nitrogen mineralisation after 5 and 3 years temporary grassland are small. Italian and perennial ryegrass, potato, silage maize, winter wheat, and several vegetables have a high nitrogen demand (i.e. >250 kg N ha-1).
    Effects of liming and nitrogen fertilizer application on soil acidity and gaseous nitrogen oxide emissions in grassland systems
    Oenema, O. ; Sapek, A. - \ 2000
    Raszyn, Poland : Instytut Melioracji i Uzytkow Zielonych (Institute for LandReclamation and Grassland Farming). - ISBN 9788385735908 - 102
    kalk - kalkmeststoffen - stikstofmeststoffen - verzuring - graslandgronden - polen - lime - liming materials - nitrogen fertilizers - acidification - grassland soils - poland
    This book contains 10 articles on the EU research project COGANOG (Controlling Gaseous Nitrogen Oxide Emissions from Grassland Farming Systems in Europe). The papers present the results of studies on the effects of liming and N fertilizer application
    Grasproductie sterk fosfaat fixerende gronden
    Wouters, A.P. - \ 2000
    Lelystad : Praktijkonderzoek Rundvee, Schapen en Paarden (Rapport / Praktijkonderzoek Rundvee, Schapen en Paarden 191) - 23
    grassen - graslanden - ruwvoer (forage) - gewasproductie - teeltsystemen - fosfaten - fosformeststoffen - fixatie - bodemeigenschappen - graslandgronden - grasses - grasslands - forage - crop production - cropping systems - phosphates - phosphorus fertilizers - fixation - soil properties - grassland soils
    De verwachting is namelijk dat aanscherping van de verliesnormen ( het betrekken van de aanvoer van kunstmestfosfaat in de MINAS regelgeving) leidt tot aanzienlijke opbrengstderving vooral op gronden waar een sterke vastlegging van fosfaat plaatsvindt.
    Phosphate losses on four grassland plots used for dairy farming : measured phosphate losses and calibration of the model ANIMO
    Salm, C. van der; Schoumans, O.F. - \ 2000
    Wageningen : Alterra (Alterra-rapport 83) - 57
    oppervlaktewater - grondwater - fosfaten - uitspoelen - melkveebedrijven - graslandgronden - surface water - groundwater - phosphates - leaching - dairy farms - grassland soils
    Changes in phosphate concentrations and pools were measured at four experimental plots from 1997 to 1999. The plots received phosphorus surpluses of 0, 10 and 20 kg ha-1 a-1. Significant changes in the phosphate pools were not yet found. Phosphate concentrations, phosphate budgets and changes in phosphate pools were simulated with the nutrient model ANIMO in combination with the hydrological model SWAP. The model simulated the order of magnitude of the measured concentrations and Pw values quite wellalthough the temporary fluctuations in orthophosporus and organic phosporus did not always correspond to the measured values. Overall leaching fluxes were simulated quite well by the model, except for the peat soils where leaching fluxes were overestimated. Leaching fluxes of orthophosporus were somewhat overestimated, whereas organic phosporus fluxes were underestimated. The simulated phosphorus balance indicated that on average 0.9 to 3.6 kg ha-1 a-1 was lost by leaching and runoff. The largest losseswere found in the sandy soils, which had the highest phosphorus contents in the lower part of the root zone.
    Vernieuwend werken : sporen van vermogen en onvermogen : een socio-materiële studie over vernieuwing in de landbouw uitgewerkt voor de westelijke veenweidegebieden
    Roep, D. - \ 2000
    Agricultural University. Promotor(en): J.D. van der Ploeg. - S.l. : S.n. - ISBN 9789058083098 - 201
    landbouwontwikkeling - landbouwproductie - marketing - innovaties - modernisering - veengronden - graslandgronden - nederland - platteland - plattelandsontwikkeling - zuid-holland - agricultural development - agricultural production - marketing - peat soils - grassland soils - rural areas - rural development - innovations - modernization - netherlands - zuid-holland

    Innovative work involves a great deal. This is the tenor of the stories in this book. It becomes obvious after reading the rather detailed descriptions of the development of a particular case of innovation (Chapters 4 and 5). The guiding principle here is how , by following the work of the innovators, a vague idea gradually takes concrete form in the continuous interaction between the processes of elaborating the idea , creating room for innovation (both Chapter 4,see figure 10), and realising the idea (Chapter 5,see figure 12). This continuous interplay is essential for the case of innovative work, regardless of its nature, effects, or location. I discuss at length the nature of innovation processes in an introduction to the ethnography (Chapter 4).

    In three, overlapping, acts, I have described as completely as possible a picture of the development of the innovative process in question: how a region-specific type of agricultural production and marketing is gradually created in and for the Westelijk Veenweidegebied (the western peatland region, a predominantly grassland area situated as a 'green heart' at the centre of the most urbanised part of the Netherlands). In doing so, I show that both the course and outcomes of the innovation process cannot be understood in isolation from its historical context; or rather, from that which preceded the innovation process and from which it originated.

    Here, this includes the post-war modernisation of agriculture and the particular social and material conditions of the western peatland region. I analyse this historical relationship in detail in Chapter 3. There I argue that the modernisation trajectory was narrowed down to the generalisation of one single development opportunity: the mass-production and marketing of cheap commodities (figure 9shows the relation with styles of farming). The existing socio-material order was altered accordingly. The particular social and material conditions of the western peatland region (which I discuss in detail and conceptualise as the historical outcome of co-production by 'nature' and 'society' infigure 7), were regarded as obstacles to be overcome in time. A 'modern' socio-material order was established along this narrow — and, at the time, unquestioned — technological trajectory (figure 6). An order embodied by for instance productive breeds of dairy cows, high-yielding grass varieties, labour-saving machinery, and various organisations involved in lobbying policy, research, and advisory bodies for particular interests. This reconstruction went along with the loss of the particular of the region, such as typical ecological values and the local knowledge to produce and market high-quality farmhouse cheese. But the further the modernisation trajectory unrolled, the more it became stuck and was hindered by all kinds of issues it was supposed to overcome. Nature and society could no longer be forced to co-operate. The modernisation trajectory turned out to be a dead end. It was time for radical change. But then the capacity of the established, 'modern' order represented an institutionalised inability to act differently.

    The particular case of innovation and all it involved must be situated in this context. I show in my ethnography how the notion of region-specific production began to take the shape of a counterbalance to the disrupting and marginalising effects of modernisation. It represented a process of particularisation of agriculture (figure 10andfigure 12) that had to be built from scratch: nature and society had to be mobilised along a different trajectory. I emphasise the crucial part played by pioneers in this; their role in the constant (re)shaping of ideas, in forging alliances, and in the search for the most appropriate structure for the realisation of their idea. I describe how they worked as a study group under the auspices of the Stichting Streekeigen Productie in het Westelijk Veenweidegebied (Foundation for Region-specific Production), set up for this purpose. Hence, they were able to use their own knowledge and skills as a starting point and to gain control over the course and outcomes of the innovation process. I indicate how they were confronted with institutionalised incapacity and opposition of the established order.

    Both capacity and incapacity have thus determined the course and outcomes of the innovation process. This is no different in other cases. Innovative work is comprehensive and far-reaching, it follows an unpredictable course, especially if new technological routes (visualised infigure 8) have to be found. The results cannot be anticipated, no matter what is claimed with the benefit of hindsight. In the Introduction, I define innovating in a general sense as building the ability to make a supposedly relevant set of interacting social and natural ordering processes to work differently (seefigure 1for a brief orfigure 2for a more extended visualisation of the conceptual framework). If this complex process of co-production and its outcome — nature and society seamlessly interwoven into a heterogeneous configuration — are not taken into account, the full extent of what is involved in innovative work cannot be understood.

    This is what I had in mind while writing this book. I wanted to point out that, since the early 1990s, we are witnessing and partaking in a radical and inclusive innovation in agriculture and the countryside, which will, once again, have a significant effect on agriculture and the countryside. The end of this dramatic process is not in sight and its outcomes are by no means certain.

    It is a process in which what once was self-evident is no longer so; a process whereby one can no longer follow blindly the once familiar ways of thinking and doing; a process that creates disruption, instability, and the disfunctioning of the established order. The once well-organised and coherent world gradually collapses, as the cement of the 'old' technology crumbles. A radical innovation causes confusion and uncertainty. This is a time when institutionalised incapacity is felt to its full extent, with all the associated frustrations; people are assiduously — and, at times, desperately — searching for a new common guiding principle with which to collect snippets of capacity in order to create a new, stable unity.

    I aim to provide insight into this dramatic turn. It is an insight that is continuously progressing, based on empirical enrichment and analytical depth, and based on the interaction between the recording of experiences and the search for conceptual tools to interpret these experiences within a wider context. In doing so, I hope to begin to make more empirically founded statements on innovative work in general from a pragmatic standpoint vis-à-vis technology, nature, and society. I argue, in the Introduction, that the existing socio-material order, in all its manifestations, can only be explained as the outcome of the interaction between previous ordering processes, as the outcome of a particular mode of ordering by which social and natural processes are inextricably interwoven by technology as mediair . I have conceptualised this as a socio-material analytical framework (figure 2), which serves as a guiding principle for my narrative. At the centre of the framework is situated my notion of a working whole : the complex set of interacting natural and social ordering processes, in which technology takes on the role of the gradually established ability to make a supposedly relevant part of the whole work effectively.

    This book offers numerous theoretical and methodological starting points for research that reaches beyond merely narrating and defining the radical innovation that takes place in agriculture and the countryside.

    De voorjaarsproduktie en het effect van ontwatering in diverse weidegebieden
    Schothorst, C.J. - \ 1980
    Wageningen : ICW (Nota / Instituut voor Cultuurtechniek en Waterhuishouding 1233) - 57
    graslanden - ontwateren - ontwaterde omstandigheden - gewassen - gewassen, groeifasen - lente - graslandgronden - landinrichting - grasslands - dewatering - drained conditions - crops - crop growth stage - spring - grassland soils - land development
    Binnen het kader van het onderzoek van de Commissie 'Herziening van evaluatie van Landinrichtingsprojecten', de Commissie 'HELP', werd op basis van proefveldgegevens een gedetailleerd onderzoek verricht naar het effect van ontwatering op de voorjaarsproduktie van diverse graslandgronden.
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