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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    Preserving Urmia Lake in a changing world : reconciling anthropogenic and climate drivers by hydrological modelling and policy assessment
    Shadkam, Somayeh - \ 2017
    Wageningen University. Promotor(en): P. Kabat, co-promotor(en): F. Ludwig; P.R. van Oel. - Wageningen : Wageningen University - ISBN 9789463431866 - 140
    lakes - hydrology - climatic change - modeling - water resources - water management - environmental protection - iran - meren - hydrologie - klimaatverandering - modelleren - watervoorraden - waterbeheer - milieubescherming - iran

    Urmia Lake, in north-western Iran, is an important internationally recognized natural area designated as a RAMSAR site and UNESCO Biosphere Reserve. Over the last 20 years, the surface area of Urmia Lake has declined by 80%. As a result, the salinity of the lake has sharply increased which is disturbing the ecosystems, local agriculture and livelihoods, regional health, as well as tourism, which could amplify economic, political and ethnic tensions in this already volatile region. In response to that, Iranian government established the ten-year “Urmia Lake Restoration Program (ULRP)” proposing six approaches in terms of controlling, protecting, surveying, studying and supplying water from other sources. This study first assessed the main reasons for the decreased inflow using the Variable Infiltration Capacity (VIC) hydrological model, including reservoirs and irrigation modules. The results showed that climate change was the main contributor to this inflow reduction. However, water resources development, particularly water use for irrigation, has played a substantial role as well. In the second step assessed Urmia lake inflow under future climate change and irrigation scenarios. Then, the (VIC) model was forced with bias-corrected climate model outputs for both the lowest (RCP2.6) and highest (RCP8.5) greenhouse-gas concentration scenarios to estimate future water availability. The results showed that the water resources plans are not robust to changes in climate. In other words, if future climate change is limited due to rapid mitigation measures (RCP2.6) the new strategy of reduction of irrigation water use can contribute to preserve Urmia Lake.

    The next step of this study assessed the quantitative impacts of ULRP by introducing a constructive framework. The framework depicts real water saving by distinguishing between water withdrawals, depletion, and demand in the context of uncertainties in future demand and supply. The results showed that although the ULRP helps to increase inflow by up to 57% it is unlikely to fully reach its target for three main reasons. The first reason is decreasing return flows due to increasing irrigation efficiency. The second reason is increased depletion which is due to neglecting the fact that agricultural water demand is currently higher than available water for agriculture. The third reason is ignoring the potential impact of climate change. However, there still can be some additional none-quantifiable barriers and challenges that may cause the failure of the restoration plan. Therefore, in the last step, this study used two types of qualitative data to explore these aspects: first, the opinions from 40 experts and the in-situ observation of some of the ULRP implementation practices. The results indicate a number of challenges for the ULRP implementation including the water use regulations and the agricultural measures. In addition, (water) demand-side measures such as crop pattern changes were more supported, as opposed to supply-side measures.

    This thesis showed that the sustainable approach to preserve Urmia Lake should incorporate both demand management (considering socioeconomic complexity) and flexible supply management strategies (to deal with uncertainties in climate variability and change) in a participatory approach. To be prepared for the future, also scenarios with reduced inflow into Urmia Lake, either due to climate change or water resources development, need to be considered to deal with considerable amounts of variability in the current system and with future changes in climate and socioeconomic conditions.

    Analysing and promoting entrepreneurship in Iranian higher education : entrepreneurial attitudes, intentions and opportunity identification
    Karimi, S. - \ 2014
    Wageningen University. Promotor(en): Martin Mulder, co-promotor(en): Harm Biemans; Thomas Lans. - Wageningen : Wageningen University - ISBN 9789461738455 - 272
    ondernemerschap - onderwijs - hoger onderwijs - studenten - attitudes - psychologie - menselijk gedrag - besluitvorming - culturele waarden - geslacht (gender) - persoonlijkheid - individuele kenmerken - iran - entrepreneurship - education - higher education - students - attitudes - psychology - human behaviour - decision making - cultural values - gender - personality - individual characteristics - iran
    Given the positive influences of entrepreneurship in tems of increasing economic growth and creating jobs, considerable efforts have been made to promote entrepreneurship in both developed and developing countries. Scholars and policymakers are also increasingly interested in the factors which influence the decision to become an entrepreneur and thus understanding why some people decide to start a business while others do not. The research reported in this dissertation therefore explored the factors which influence the entrepreneurial intentions of students in higher education in the developing country of Iran.
    Spatio-temporal variation of wheat and silage maize water requirement using CGMS model
    Sargordi, F. ; Farhadi Bansouleh, B.F. ; Sharifi, M.A. ; Keulen, H. van - \ 2013
    International Journal of Plant Production 7 (2013)2. - ISSN 1735-6814 - p. 207 - 224.
    north china plain - growth simulation - climate-change - crop - variables - impacts - yield - iran
    The Crop Growth Monitoring System (CGMS) has been applied for spatial biophysical resource analysis of Borkhar & Meymeh district in Esfahan province, Iran. The potentially suitable area for agriculture in the district has been divided into 128 homogeneous land units in terms of soil (physical characteristics), weather and administrative unit. Crop parameters required in the WOFOST simulation model for winter wheat and silage maize, have been calibrated based on experimental data from the study area. The study area has been classified into three cropping calendar zones based on average annual temperature, altitude and latitude. For each zone, a sowing date has been defined for each crop as the starting point of crop growth simulation. Growth of these crops has been simulated for the potential situation in each land unit for 20 years of historical daily weather data. Daily potential evapotranspiration and irrigation requirements of each crop per land unit have been calculated in a postsimulation, on the basis of model outputs. Outputs of the model are crop yield (marketable yield and total biomass) and irrigation requirements per decade. Spatial and temporal variation in irrigation requirements has been analyzed. The temporal variation in crop water requirements is larger than the spati3al variation.
    Isolation, identification and activity of natural antioxidants from horehound (Marrubium vulgare L.) cultivated in Lithuania
    Pukalskas, A. ; Venskutonis, P.R. ; Salido, S. ; Waard, P. de; Beek, T.A. van - \ 2012
    Food Chemistry 130 (2012)3. - ISSN 0308-8146 - p. 695 - 701.
    plant-extracts - liquid-chromatography - glycosides - online - leaves - iran - oils
    In an earlier screening of Lithuanian plants, horehound (Marrubium vulgare) showed good antioxidant activity and as this species is used in herbal teas and cough pastilles it was selected for further investigation. Some fractions of the aerial parts were strong scavengers of the model free radicals DPPH and ABTS'. Activity in the beta-carotene bleaching assay and the rapeseed oil oxidation assay was lower. Several active compounds were observed in the crude methanol-water extract, and in butanol and methyl tert-butyl ether fractions using HPLC with on-line radical scavenging detection. After multi-step fractionation of these fractions five compounds possessing radical scavenging activity were purified and their structures were elucidated by NMR and MS as 5,6-dihydroxy-7,4'-dimethoxyflavone (syn. ladanein), 7-O-beta-glucopyranosyl luteolin, 7-O-beta-glucuronyl luteolin, verbascoside and forsythoside B. Their activities were tested in off-line DPPH and ABTS(+) free radical scavenging assays, and compared with the antioxidants rosmarinic acid and Trolox. (C) 2011 Elsevier Ltd. All rights reserved.
    Future Projections of Urban Waste Flows aand their Impacts in African Metropolises Cities
    Oyoo, R. ; Leemans, R. ; Mol, A.P.J. - \ 2011
    International Journal Environmental Research 5 (2011)3. - ISSN 1735-6865 - p. 705 - 724.
    solid-waste - management - issues - city - iran
    This paper presents future trends of urban wastes and their impacts on the environment of African cities using plausible mitigation scenarios. To accomplish this, an integrated dynamic model for urban waste flows was developed, tested, calibrated and validated. Its parameter sensitivity was analyzed. Using population projection up to 2052 with different levels of technological implementation, policy enforcement and awareness raising, four runs were executed. The “business as usual” run showed that with no additional mitigation measures, the environmental quality in Kampala and Dar es salaam Cities deteriorates. The “more enforcement” and “more collection” scenarios showed good reduction in environmental loads but they perform less well in resource recovery. The “proper management” scenario that combines enhanced technological implementation, awareness raising and policy enforcement, produced the smallest environmental loads, and recovered the largest amount of resources. Thus, the city authorities, general public, community based organisations and Non-governmental organizations would have to increase their efforts in finances and commitment to improve the urban environmental quality and increase resource recovery.
    Distributed agro-hydrological modeling with SWAP to improve water and salt management of the Voshmgir Irrigaton and Drainage Network in Northern Iran
    Noory, H. ; Zee, S.E.A.T.M. van der; Liaghat, A.M. ; Parsinejad, M. ; Dam, J.C. van - \ 2011
    Agricultural Water Management 98 (2011)6. - ISSN 0378-3774 - p. 1062 - 1070.
    agrohydrologie - irrigatie - landbouwgrond - verzilting - modellen - iran - agrohydrology - irrigation - agricultural land - salinization - models - iran - hydraulic conductivity - productivity - system - soils
    The agro-hydrological model SWAP was used in a distributed manner to quantify irrigation water management effects on the water and salt balances of the Voshmgir Network of North Iran during the agricultural year 2006–2007. Field experiments, satellite images and geographical data were processed into input data for 10 uniform simulation areas. As simulated mean annual drainage water (312 mm) of the entire area was only 14% smaller than measured (356 mm), its distribution over the drainage units was well reproduced, and simulated and measured groundwater levels agreed well. Currently, water management leads to excessive irrigation (621–1436 mm year-1), and leaching as well as high salinity of shallow groundwater are responsible for large amounts of drainage water (25–59%) and salts (44–752 mg cm-2). Focused water management can decrease mean drainage water (22–48%) and salts (30–49%), compared with current water management without adverse effects on relative transpiration and root zone salinity
    Towards reflexive land and water management in Iran : linking technology, governance and culture
    Balali, M.R. - \ 2009
    Wageningen University. Promotor(en): Michiel Korthals; Jozef Keulartz. - [S.l.] : S.n. - ISBN 9789085854272 - 245
    grondbeheer - waterbeheer - hulpbronnenbeheer - technologie - cultuur - iran - governance - land management - water management - resource management - technology - culture - iran - governance

    Key words: Qanat, land and water, sustainability, Industrial and reflexive modernity

    This PhD thesis is concerned with the causes and consequences of the environmental crisis and explores possible trajectories towards sustainable land and water management in Iran and other countries of the Middle East and North Africa (MENA). The basic assumption underlying the conceptual framework of this thesis is that soil and water technologies, social institutions and environmental mentalities are strongly interconnected; they co-evolve, shaping and reshaping one another in the process. The main research question concerns the changes within this network of technologies, institutions and mentalities that are required for a successful transition from industrial modernity to what sociologists like Ulrich Beck, Anthony Giddens and Scott Lash have called ‘reflexive’ modernity. In order to examine the possibilities and problems of a reflexive turn in land and water management in Iran and other MENA-countries, large-scale empirical studies were conducted among farmers and village informants, soil and water experts, and policymakers.

    Development of a spatial planning support system for agricultural policy formulation related to land and water resources in Borkhar & Meymeh district, Iran
    Farhadi Bansouleh, B.F. - \ 2009
    Wageningen University. Promotor(en): Herman van Keulen, co-promotor(en): M.A. Sharafi. - [S.l.] : S.n. - ISBN 9789085853817 - 267
    ruimtelijke ordening - landbouwbeleid - landbouwontwikkeling - simulatiemodellen - iran - systeemontwikkeling - systeeminnovatie - beleidsonderzoek - physical planning - agricultural policy - agricultural development - simulation models - iran - system development - system innovation - policy research
    In this study, a system was developed to support agricultural planners and
    policy makers in land resource analysis, policy formulation, identification of
    possible policy measures and policy impact analysis. The research is part of a
    larger programme, aiming at development of a model system to support
    agricultural policy formulation at national level. The current study focused on
    methodology development and its implementation in Borkhar & Meymeh
    district in Esfahan province, Iran.
    The system comprises three main components, i.e. resource analysis, policy
    impact assessment and policy evaluation. The biophysical resource analysis was
    carried out using CGMS, the Crop Growth Monitoring System which includes
    WOFOST, a generic crop growth simulation model. This model simulates
    growth of annual crops in the potential and water-limited production situations,
    based on daily weather data, crop characteristics and soil physical
    characteristics. For this purpose, crop characteristics of winter wheat and winter
    barley were calibrated based on research data from the agro-meteorological
    research center of Kaboutar Abad, Esfahan, Iran. Crop characteristics of silage
    maize, sugar beet, sunflower and potato were calibrated based on yields of the
    best agricultural producers in the region.
    For the weather stations in which solar radiation was not measured, it was
    estimated from sunshine-hours or temperature, using empirical relations. A
    sensitivity analysis on method of solar radiation estimation was carried out to
    test model performance in terms of simulated crop yield and water requirements
    for winter barley and sugar beet as representatives of winter and summer crops,
    respectively. Results of this analysis showed that the maximum difference in
    simulated crop yield based on estimated and measured solar radiation is less
    than 10%.
    CGMS was used for land resource analysis at the regional (district) scale. The
    potentially suitable area for agriculture in the district was identified and
    classified into 128 homogenous units (referred to in this study as Elementary
    Mapping Units, EMU) in terms of soil, weather and administrative unit. For
    each EMU, soil physical characteristics were derived from available soil maps
    and soil analyses reports. Daily weather characteristics (maximum and
    minimum temperature, vapor pressure, wind speed, rainfall, and solar radiation)
    were generated for the centre of each EMU by interpolation of daily weather
    data of 33 weather stations, located in and around the district. CGMS was then
    modified to allow calculation of irrigated crop yields. Yields of major crops and
    water requirements per decade were simulated using CGMS for three irrigation
    regimes (full irrigation, 20% and 40% deficit irrigation). Fertilizer requirements
    for the three macro-nutrients, nitrogen, phosphorus and potassium, for each
    level of crop production were estimated based on soil chemical characteristics,
    crop yields and nutrient content in economic crop products and crop residues.
    An alternative methodology was developed for spatial estimation of crop yields,
    water and fertilizer requirements of crops (alfalfa, melon, watermelon, and
    colza) that could not be simulated by CGMS, either because of model
    limitations or lack of data for model calibration. The ratio of current and
    potential crop yields, referred to as production efficiency, was used as an
    indicator of management ability of farmers and was used in farm classification.
    The policy formulation process consists of three steps: i) selection of policy
    objectives, ii) identification of policy instruments and iii) assessment and
    analysis of their impacts. In this study, policy objectives and relevant policy
    instruments were derived from the latest agricultural development documents. A
    model was developed to assess the impacts of policy instruments and another
    model for analysis of these impacts from different perspectives. As reactions of
    farmers to policy instruments may be different, depending on their socioeconomic
    situation and the biophysical characteristics of their land, a planning
    (modelling) unit was defined, homogenous in terms of biophysical and socioeconomic
    characteristics. For this purpose, farms belonging to each of the
    agricultural production systems (e.g., traditional, cooperative and agroindustrial)
    were classified into farm types, based on land and water availability,
    overall production efficiency and average net income per ha. These farm types
    were combined with land units to form the basic units of analysis, i.e. farm
    type-land units (FTLU), homogenous in terms of biophysical potential, as well
    as in resource endowments and management ability of farmers.
    A distributed linear programming model was developed to assess policy
    impacts by simulating the response of the various farm types to specific policy
    instruments. This model is optimizing a utility function, composed of a
    combination of net income and production cost, subject to various constraints at
    different spatial scales (e.g., farm type-land unit, farm type, village, and subdistrict).
    The model was validated based on the conditions of the year 2002-03
    by comparing simulated crop yields and total crop production in Borkhar subdistrict
    with detailed agricultural census data. Indicators, representing the
    effect/impact of policy instruments on economic, social, and environmental
    objectives of various stakeholders were selected and quantified in a post-model
    In a model experiment, the reactions of the different farm types to three policy
    instruments, aiming at increasing agricultural water productivity in Borkhar
    sub-district were simulated. A multi-criteria evaluation technique was used for
    policy analysis through overall assessment of the various economic, social and
    environmental indicators to evaluate the effectiveness of various policy
    The developed system represents a further step in the development of computeraided
    decision support systems for land use analysis that have received ample
    attention in the research community, in response to the perceived needs of
    policy makers. The consultations with planners in the course of the study, leads
    to the conclusion, however, that still a long way has to be gone to bridge the gap
    between the policy makers that are asking questions that land use modelers can
    not answer and the land use modelers that are generating answers to questions
    that policy makers are not (willing to) ask(ing).
    Improving the utilization of Silver carp (Hypopthalmichthys Molitrix) and other under-utilized fish species, especially Fresh water Bream (Abramis brama)
    Bartels, P.V. ; Kals, J. - \ 2008
    Wageningen : Agrotechnology & Food Sciences Group (Rapport / Agrotechnology and Food Sciences Group (AFSG) 767) - 71
    visverwerkende industrie - visverwerking - visproductie - visproducten - nieuwe producten - dierlijke eiwitten - snijden - voedselverwerking - karper - iran - fish industry - fish processing - fish production - fish products - new products - animal proteins - cutting - food processing - carp - iran
    Virus-host interactions of tomato yellow ring virus, a new tospovirus from Iran
    Hassani-Mehraban, A. - \ 2008
    Wageningen University. Promotor(en): R.W. Goldbach, co-promotor(en): Richard Kormelink. - [S.l.] : S.n. - ISBN 9789085049395 - 130
    tospovirus - bunyaviridae - identificatie - waardplanten - gastheer parasiet relaties - iran - plant-microbe interacties - tospovirus - bunyaviridae - identification - host plants - host parasite relationships - iran - plant-microbe interactions
    During the past decades, an increasing number of new tospovirus species occurring in various agricultural and horticultural crops have been reported. The emergence of new tospoviruses may be attributed to intensified international trading, to increasing problems to control their thrips vectors, but certainly also by better recognition based on new diagnostic tools.
    The works presented in the thesis first focused on comprehensive characterisation and identification of a tospovirus species occurring in different crops in Iran, and next on transgenic approaches to control this virus.
    In Chapter 2, five presumed Iranian tospovirus isolates from tomato, chrysanthemum, gazania, soybean and potato, collected in 2002, were analysed. All isolates induced necrotic local lesions on Petunia hybrida, indicative for tospoviruses. None of the available antisera against known tospoviruses reacted with the isolates, suggesting that if these were tospoviruses, they should belong to a novel species. As a next step the viral nucleoprotein (N) gene of the tomato isolate was cloned and sequenced and this information demonstrated that it represented a new tospovirus species for which the name Tomato yellow ring virus (TYRV) was proposed. Subsequently the N gene sequences of the chrysanthemum and gazania isolates were also obtained and showed these isolates to represent TYRV as well. Back-inoculation of the tomato isolate induced resembling chlorotic and necrotic spots on leaves and yellow rings on the tomato fruits. The complete S RNA sequence of this isolate revealed the generic topology of a tospoviral S RNA, containing both NSS (suppressor of silencing) and N (nucleocapsid) genes separated by a long non-coding intergenic region including a predicted hairpin structure. Multiple sequence alignment of the N protein of TYRV with those of established tospovirus species revealed the closest relationship (74% identity) to Iris yellow spot virus (IYSV).
    In chapter 3, the isolates from soybean and potato were analysed. Although in ELISA assays these isolates scored positive with antiserum raised against the TYRV-tomato isolate, they failed to amplify in RT-PCR when using primers derived from the latter. The N gene sequences of these isolates indeed revealed a sequence divergence of 8% compared to that of TYRV-tomato, indicating these two belonged to different strains of TYRV (denoted TYRV-s, while the strain occurring in tomato was named TYRV-t). Additional differences between the two strains were found in their respective S RNA non-coding intergenic regions. Differences in their host range and symptom expression underscored the decision to treat them as separate strains. A preliminary cross-protection study indicated that TYRV-t and TYRV-s mutually exclude each other, indicating that the strains represent stable, isolated lineages which do not easily converge despite their geographical overlap.
    In chapter 4, extended inverted repeat transgenic cassettes for broad tospoviral resistance were constructed and tested. These transgene cassettes contained partial N gene sequences from 5 different tomato-infecting tospoviruses, including TYRV-t from Iran, in such arrangement that transgenic expression would deliver a ds hairpin RNA. Using Nicotiana benthamiana as a model plant, transgenic lines harboring an inverted repeat construct interspaced with a sense-oriented intron were obtained with high frequencies of resistance up to 100% for all 5 tospoviruses in F2. By analysing the siRNA content of the transgenic plants it could be verified that the transgenic resistance was based on RNA silencing (or shortly RNAi). Whilst these transgenics were fully resistant to TYRV-t (whose N gene sequence was used in the transgene cassette), they were fully susceptible to TYRV-s, demonstrating again how narrow transgenic resistance based on RNAi is. Surprisingly upon co-inoculation with TYRV-s, TYRV-t also could overcome the transgenic resistance. Mass spectrometric analysis of viral ribonucleocapsid protein (RNP) purified from a mixed-infected transgenic line revealed that the N protein of both strains were present and hence hetero-encapsidation as possible mechanism to rescue TYRV-t from these plants could be excluded. Experiments involving the expression of the viral suppressor protein (NSs) from TYRV-s using a PVX vector, indicated that rescue of TYRV-t by TYRV-s was based on the expression of the TYRV-s RNAi suppressor.
    Since most of the operational transgenic tospovirus resistance approaches are based on RNAi, involving the production of transgenic viral siRNAs, in chapter 5 the production and involvement of viral siRNA molecules during a natural tospovirus infection process was investigated. Special attention was given to the intergenic hairpin region of the S RNA segment. Total small RNA was isolated from TYRV-t infected N. benthamiana and mapped to the S RNA segment. These studies demonstrated the occurrence of a hot spot for siRNA induction within the S RNA, but surprisingly this hotspot was not mapped in the IGR hairpin but at the start of NSS ORF where a much shorter hairpin structure was predicted. Surprisingly, fewest siRNAs mapped to the intergenic region which is predicted to fold into a long hairpin, despite additional experiments involving DICER cleavage by Drosophila melanogaster embryo extract and YFP (yellow fluorescent protein)-hairpin constructs indicating this region to be a potential inducer and target for RNAi.
    In chapter 6, the observations done in the experimental chapters are discussed in a broader context and a model for tospovirus-induced RNA silencing presented.

    Effects of wastewater irrigation on soil sodicity and nutrient leaching in calcareous soils
    Jalali, M. ; Merikhpour, H. ; Kaledhonkar, M.J. ; Zee, S.E.A.T.M. van der - \ 2008
    Agricultural Water Management 95 (2008)2. - ISSN 0378-3774 - p. 143 - 153.
    cation-exchange - reclamation - groundwater - flow - iran
    Soil column studies were conducted with two soils to assess the effects of irrigation with wastewater on soil and groundwater quality. Upon the application of wastewater, exchange occurred between solution sodium (Na+) and exchangeable cations (Ca2+, Mg2+, K+), whereby these cations were released into solution. The average exchangeable sodium percentage (ESP) of the soils increased during leaching from 9 to 21 and 28.8 to 29.7 after applying 5.0 and 3.5 l (about 7 and 6 pore volumes) of wastewater to the soils columns, respectively. Adverse effect of high Na+ concentration in the wastewater on raising ESP was less pronounced in the soil having initial high ESP than in the soil with low initial ESP. Salinity of the soils was also increased with the application of wastewater and Mg2+ and K+ were leached from the soils. These losses would be more severe on soils having a low cation exchange capacity and if, uncorrected could lead eventually to their deficiencies for plant growth. When the soil columns were leached with distilled water the flow rate of one soil decreased to zero after 2.2 pore volume indicating damage to soil structure. Irrigation with wastewater, which is generally more sodic and saline than regional groundwater, increases the rate of soil sodification of shallow groundwater. A relatively simple chromatographic model was used to estimate final ESP profiles in the soils assuming the condition of local equilibrium. This approach had a limited success for one of the soil. Since the final leached concentrations are in good agreement with those of wastewater, we attribute these differences to non-uniform flow through the column. In terms of practical soil and water management, our study reveals that relatively simple means can be useful to predict the water quality in soils, their discharge to ground water, and the hazard of soil structure deterioration
    Molecular and biological comparison of two Tomato Yellow Ring Virus (TYRV) isolates: challenging the Tospovirus species concept
    Hassani-Mehraban, A. ; Saaijer, J. ; Peters, D. ; Goldbach, R.W. ; Kormelink, R.J.M. - \ 2007
    Archives of Virology 152 (2007)1. - ISSN 0304-8608 - p. 85 - 96.
    spotted-wilt-virus - s-rna segment - intergenic region - rt-pcr - sequence - iran - identification - suppressor - capsicum - protein
    Two strains of Tomato yellow ring virus (TYRV, genus Tospovirus), one from tomato (referred to as TYRV-t) and the other from soybean and potato (denoted TYRV-s), collected from different geographical regions in Iran, were compared. Their genomic S RNA segments differed in size by 55 nucleotides. Comparison of the S RNA intergenic regions revealed the absence of a stretch of 115 nucleotides within the S RNA segment of TYRV-s and, conversely, of 56 nts in that of TYRV-t, apparently a stable genetic difference as it was also found in another isolate of TYRV-s collected from potato. Sequence comparison of the N protein ORFs revealed an identity of 92% between the N proteins of both strains, and the observed strong cross-reaction of TYRV-s in DAS-ELISA with a polyclonal antiserum directed against the TYRV-t N protein confirmed this high identity. Host range analysis revealed several differences, e.g. TYRV-s, but not TYRV-t, being able to systemically infect Nicotiana species, and TYRV-s being localised in tomato. The observed molecular and biological differences of both viruses call into question the currently used criteria for Tospovirus species demarcation
    Towards a competency profile for the role of instruction of agricultural extension professionals in Asfahan
    Karbasioun, M. - \ 2007
    Wageningen University. Promotor(en): Martin Mulder, co-promotor(en): Harm Biemans. - [S.l.] : S.n. - ISBN 9789085046028 - 285
    vaardigheidsonderwijs - onderwijsplanning - voorlichtingskunde - voorlichters - vakbekwaamheid - landbouw - voorlichting - iran - landbouwvoorlichting - competency based education - educational planning - extension education - extension agents - professional competence - agriculture - extension - iran - agricultural extension
    This thesis is aimed at developing a competency profile for instructors in the agricultural extension service in theprovinceofEsfahaninIran. These instructors are part-time subject matter specialists who cooperate with the Ministry of Agriculture and teach short-term extension courses in different disciplines to farmers. Previous research revealed that the target group of the research generally experience many problems in their role of instructor during extension courses for farmers. The PhD project was conducted to develop a competency profile for this role in the next three to five years. In doing that, a comprehensive review of the literature was carried out, the competency models presented by McLagan (1982) were selected and adjusted to the Iranian extension system, and were tested for the role of instruction. To increase the reliability of the model, different respondents were involved: participating and non-participating farmers in extension courses, agricultural experts, agricultural managers, and instructors.

    The research carried out in the project is presented in this book, which contains three main parts and nine chapters. The first chapter is the general introduction, which provides the literature review, problem statement, research design, definition of concepts, study area and the outline of the thesis. Part one of the thesis presents four farmers' studies, part two encompasses two agricultural experts' studies and part three includes the key study of the research and the synthesis. In the synthesis chapter the implications of all previous chapters about the competency profile of the target group are aggregated and the model is triangulated.

    The findings of this research show that the evolution of agricultural development and extension has not been convincing during the last decade and that farmers were confronted with many unexpected changes and problems in their work. The Ministry of Agriculture (MAJ) has supported farmers to a limited extent, and much more support is needed in the future. However, the governmental extension services are assumed as being the most important information source for farmers. Farmers were generally pleased with the services of the extension organization and with their courses, as well as with the instructors, but they expect revisions in evaluation methods, the use of instructional technologies, and the duration of the courses and follow up strategies delivered by the instructors. The most important motives of farmers for participation in the courses were performance improvement and personal development.

    Respondents of the key study (chapter eight) gave high scores to all components (future forces, ethical issues, outputs, standards and competencies) of the competency profile of the instructors. It was concluded that instructors should perform additional roles apart from instruction. New general and common competencies were inserted into the final version of the competency profile of the instructors. Ultimately, this research revealed that designing a common competency profile for instructors is possible but the profile should be differentiated based on the stratification of the farmer population by variables such as gender, age, level of education, and motives for course participation. Further research is proposed both for the role of instructors and other human resource professionals in the field of agricultural extension inIran. Also, repeating this study at national and international level, also in different sectors, could enhance professional development in various occupations and thereby socio-economic development in these sectors, and could further elaborate the instrumental use of the model.
    Decision Support System for Floodwater Spreading Site Selection in Iran
    Kheirkhah Zarkesh, M. - \ 2005
    Wageningen University. Promotor(en): Leo Stroosnijder, co-promotor(en): A.M.J. Meijerink; M.A. Sharifi. - Enschede : ITC - ISBN 9789085042563 - 259
    hoogwaterbeheersing - inundatie - waterbeheer - besluitvorming - simulatiemodellen - iran - stroomvlakten - overstroomde gronden - beslissingsondersteunende systemen - flood control - flooding - water management - decision making - simulation models - iran - floodplains - flooded land - decision support systems

    Keywords: DSS, remote sensing, GIS. spatial multi-criteria evaluation, analytical hierarchy process, floodwater spreading, groundwater recharge, Iran.
    Most aquifers of semi-arid Iran suffer from over-exploitation of groundwater for irrigation. It is therefore important to augment the groundwater resource by artificial recharge, using flood waters that flow into salt lakes or in the sea. The recharge schemes consist generally of diversion of part of the flood discharges of ephemeral rivers in small to medium sized catchments onto infiltration basins.
    Apart from recharge of groundwater, supporting food production and drinking water supplies, the schemes have other benefits, such as mitigation of flood damages and 'greening of the desert'. Many governments, including the one of Iran, place now much emphasis on increasing the number of floodwater spreading schemes.
    A large number of factors play a role in the selection of the most suitable sites for deciding on investment in a scheme. These factors pertain to earth science (geology, geomorphology, soils), to hydrology (runoff and sediment yield, infi!tration and groundwater conditions) and to socio-economic aspects (irrigated agriculture, flood damage mitigation, environment, job creation and so on). Hence, the decision depends on criteria ofdiverse nature.
    This thesis deals with developing a Decision Support System (DSS) to assist decisions as to where the most suitable catchments and associated infiltration areas are and to work out options of types of schemes, which are adjusted to the characteristics ofthe selected infiltration area (the site available).
    After discussion of the bio-physical setting for flood spreading schemes in the Introduction (Chapter 1), attention is given to the selection ofthe desired approach for multi-criteria evaluation in Chapter 2. The Analytical Hierarchical Processes (AHP) approach was considered to be appropriate for the problem at hand and use was made of the spatial extension of this approach in a GIS environment, after structuring all the major criteria for a flood spreading scheme.
    Of key importance is of course the expected infiltration of flood water diverted. For such an a-priori estimate the effect of soil textures in a soil column on infiltration and percolation have to be made, as well as an estimate of the effects of sedimentation of clay and sand in a scheme, as well as effect of inundation depth and flooding frequency. One-dimensional soil modelling was done with the SWAP model. Chapter 3, using two pedo-transfer functions for the hydraulic parameters based on textures. It was found that for coarse textured soils there was reasonable agreement between functions used, but quite some differences were found for the soils containing clay and silt. As expected, recharge efficiency was positively affected by inundation depth and by rapid succession of inundations.
    Because simulation results differed, the recharge of the complex and large Sorkhehesar scheme was analysed, by developing a spreadsheet programme to work out depths, areas and duration of inundation. Chapter 4. It was found that the Mnalem-van Genuchten transfer function was the most appropriate one.
    Given the large number of ephemeral rivers draining hilly catchments and passing through alluvial areas, is necessary to first use a rapid screening method to obtain zones which contain promising areas, for which the main criteria are applicable. The screening depends heavily on interpretation of remotely sensed images, which have the advantage that various aspects are presented in a synoptic view. The interpretation has to have a firm footing in earth science because runoff and sediment delivery processes have to be estimated in qualitative terms, as well as aquifer properties. A number of examples from Iran have been described in Chapter 5, highlighting the importance of transmission losses.
    In order to select the most suitable area among the promising ones, the spatial AHP was applied in the Varamin zone under consideration of a multitude of criteria, in Chapter 6. The difficulty in the application was to develop and specify the preferences that are the base of the relative importance values for all the decision criteria involved at different levels, once the various factors had been estimated using standard hydrological and other methods. The use of the linguistic measures of preferences in the pair-wise comparisons made it possible to implement the full procedure, even though data differed much in nature, consistency and quality. In the Varamin zone, the Chandab catchment and infiltration area came out as the ''most satisfying" area; it had the highest sum of utilities for three of the four objectives and the highest score in a combination scenario.
    For the Chandab infiltration site, a spreadsheet model was developed to work out various options with regard to type of scheme (shallow basin or deep basin type) and size of scheme, resulting in the expected volumes of recharge during the lifetime of the scheme by assuming desilting operations. Of the additional benefits, the flood damage mitigation could be expressed in monetary terms, and that benefit had a profound effect on the cost per unit volume of recharge water if one opts for the two large sized scheme designs.
    To our knowledge, this study presents for the first time information on costs and benefits of a flood water spreading scheme in Iran in a structured manner of various designs adjusted to a particular site.
    The final conclusion (Chapter 8) states that the DSS described here, with its three stages of increasing focus and associated data requirements and with the approach for evaluation using a multitude of criteria of diverse nature, has proven to be applicable and an efficient way to select the most appropriate alternatives for making a choice for investment in a flood spreading scheme. Although the emphasis was on Iranian conditions, the DSS is essentially of generic nature and may be applied ~ mutatis mutandis- to other semi arid regions.
    Quality, energy requirement and costs of drying tarragon (Artemisia dracunculus L)
    ArabHosseini, A. - \ 2005
    Wageningen University. Promotor(en): J. Mueller, co-promotor(en): W. Huisman; Ton van Boxtel. - Wageningen : - ISBN 9789085042976 - 115
    dragon - artemisia dracunculus - energieproductiekosten - drogen - voedselbewaring - droogkwaliteit - luchtdroging - extractie - etherische oliën - keukenkruiden - medicinale planten - iran - nederland - tarragon - artemisia dracunculus - energy cost of production - drying - food preservation - drying quality - air drying - extraction - essential oils - culinary herbs - medicinal plants - iran - netherlands
    Tarragon ( Artemisia dracunculus L.) is a favorite herbal and medicinal plant. Drying is necessary to achieve longer shelf life with high quality, preserving the original flavor. Essential oil content and color are the most important parameters that define the quality of herbal and medicinal plants. Hot air batch drying is the most common drying method for these plants but affects the essential oil content and color. The drying conditions affect essential oil content and color as well as the energy consumption and costs. Process engineers and farmers need to know how they have to dry to obtain the best quality. The objective of this work is to investigate the conditions for optimal drying in terms of quality, energy consumption and costs.

    Adsorption and desorption experiments were done to find the equilibrium moisture content and water exchange between the material and surrounding air during drying and storage at temperatures of 25ºC to 70ºC and relative humidities of 5% to 90%. Drying of tarragon leaves and chopped plants was investigated separately and the best model was selected from the drying equations in literature. The effect of drying temperature and relative humidity on the essential oil content and color change was studied. Experiments were done at temperatures of 40ºC to 90ºC and the optimal conditions were. Long‑term effects of the drying conditions were also investigated during the storage time. Material dried at 45, 60 and 90ºC was stored and the essential oil content and color of the material was measured after 15, 30, 60 and 120 days of storage. Drying at 45ºC was found as the best condition based on the changes of essential oil and color during drying and storage.

    Optimization of drying of tarragon was studied based on the results of the sorption isotherms, drying equations and the changes of essential oil content and color during drying and storage. Models were made for the drying process, energy consumption and cost calculation. The current conditions in The Netherlands andIranwere applied for various drying scenarios. The simulation model was run at selected ranges of temperature, humidity ratio, air speed and bed heights, with and without recirculation of the drying air. Considering the quality of dried material and costs, a temperature of 50ºC was found as the optimal temperature for drying tarragon. The costs per kg dried product was about three times higher for The Netherlands compared toIran. The recirculation is less important inIranbecause the ambient air has a higher drying potential and energy prices are lower.

    A planning support system for rangeland allocation in Iran : case of Chadegan sub-region
    Farahpour, M. - \ 2002
    Wageningen University. Promotor(en): H. van Keulen; A.M. Sharifi. - S.l. : S.n. - ISBN 9789058086297 - 186
    extensieve weiden - landgebruik - landgebruiksplanning - regionale planning - hulpbronnenbeheer - optimalisatie - optimalisatiemethoden - planning - modellen - iran - beslissingsondersteunende systemen - rangelands - land use - land use planning - regional planning - resource management - optimization - optimization methods - planning - models - iran - decision support systems

    Rangelands, like other natural resources are subject to many changes. In Iran, one of the changes is the land tenure reform, that may have significant effects on both the land and the land user. Land tenure changes not only affect the life of the present, but also that of next generations, and involves very complex decision making. This decision should lead to a sustainable use of the land and contribute to the livelihood of the present and future generations. In this context a planning support system is being developed for rangeland allocation in Iran to support its rangeland tenure reform. The system is composed of three modules: land evaluation module, district planning module and local planning module.

    The land evaluation module works in a GIS environment and uses the FAO methodology for land evaluation . It is mainly based on biophysical characteristics of the land use system. However, socio-economic factors, in terms of the effect of human intervention on the current status of the land have also been taken into account.

    The district planning module comprises three sub-modules: the planning sub-module, the grazing sub-module and multicriteria evaluation (MCE) sub-module. The planning sub-module is an optimisation model that allows examination of the degree of realisation of the various objectives of stakeholders, and generates alternative solutions. For each alternative, the grazing capacity of the land is assessed through the grazing sub-module, that translates the forage production into grazing capacity. The MCE module ranks all alternatives, taking into account their advantages and disadvantages, and provides a platform for decision makers to judge the trade-offs between alternatives and supports rational decision-making. This leads to a land use pattern, which is in line with the existing government policies and satisfying the needs and desires of the people in the district.

    The local planning module also comprises of three sub-modules: Land allocation, economic enterprise and land improvement. The land allocation sub-module transforms the district land use pattern into a local land use plan. The economic enterprise sub-module determines the appropriate size of the land holding for each household on each land mapping unit. Finally, the land improvement sub-module provides information on the status and impact of the programme at each specified point in time and space.

    Searching for Slender-billed Curlews in Iran, January-February 2000
    Have, T.M. van der; Keijl, G.O. ; Mansoori, J. ; Morozov, V.V. - \ 2001
    Zeist : WIWO (WIWO-report 72 )
    numenius - vogels - watervogels - wetlands - inventarisaties - monitoring - iran - waadvogels - numenius - birds - waterfowl - wetlands - inventories - monitoring - iran - waders
    Factors affecting the availability and relevance of technology for wheat producers in Iran : a study of the Agricultural Knowledge and Information System (AKIS)
    Mirikhoozani, S.A. - \ 1993
    Agricultural University. Promotor(en): N.G. Röling. - S.l. : Mirikhoozani - ISBN 9789054851929 - 241
    voedselproductie - beleid inzake voedsel - overheidsbeleid - landbouwbeleid - agrarisch recht - triticum aestivum - tarwe - hexaploïdie - iran - food production - food policy - government policy - agricultural policy - agricultural law - triticum aestivum - wheat - hexaploidy - iran

    A combination of socio-economic, cultural and political reasons have led Iran to pursue two important national objectives: self-sufficiency in food and support poor farmers. The chosen operational strategy aims at intensification of agriculture by creating conditions for productivity increase. This has been done by introducing high yielding varieties and high external inputs and by setting up various support institutions, in order to provide access to goods and services and a regulatory structure of laws and incentives.

    However, the efforts of the government have not resulted in the achievement of the national objectives. At the national level, two problems remain: the country imports a large amount of food and the production of small farmers is low. At the field level, the continuing existence of yield gaps is the problem.

    At the field level, by examining the claims and benefits of the technologies introduced and of the institutional efforts made, the study reveals that farmers, especially small farmers, have difficulty in adopting the technologies. The lack of adoption results from their lack of access to the development mix including the incentive structure, market, inputs, irrigation, relevant technologies, etc. This in turn has its root in institutional and policy factors.

    At the institutional level, we observe that the research, extension, training institutions (as the institutions directly involved in providing access to relevant technologies), and farmers, lack synergy amongst their tasks. This results from problems in task differentiation amongst the actors, poor integration between the tasks of the actors and weak or no coordination amongst the actors. Furthermore, the actors lack a conducive environment in which to perform effectively. A number of factors related to policy-making, bureaucratic and political structures, the institutions in charge of providing goods and services for farmers, the black market and the national and international research institutes, further hinder the effective performance of the actors.

    At the policy level, the situation is problematic with respect to both general and technology policies. In all, we can say the policy environment is not conducive to the achievement of the stated objectives.

    Development of an appropriate resource information system to support agricultural management at farm enterprise level : a prototype design for a decision support system in Moghan Agro-industrial Complex, Iran
    Sharifi, M.A. - \ 1992
    Agricultural University. Promotor(en): M. Molenaar; H. van Keulen. - S.l. : Sharifi - ISBN 9789061640745 - 217
    geografische informatiesystemen - informatiesystemen - automatisering - bedrijfsvoering - ruimtelijke ordening - landgebruik - zonering - oogsttoename - oogstverliezen - opbrengsten - landevaluatie - grondvermogen - bodemgeschiktheid - landgebruiksplanning - ontwerp - ontwikkeling - programma's - modellen - onderzoek - agrarische bedrijfsvoering - modernisering - innovaties - besluitvorming - operationeel onderzoek - simulatie - werkschema - lineair programmeren - iran - geographical information systems - information systems - automation - management - physical planning - land use - zoning - yield increases - yield losses - yields - land evaluation - land capability - soil suitability - land use planning - design - development - programs - models - research - farm management - modernization - innovations - decision making - operations research - simulation - work flow - linear programming - iran

    This thesis describes development of and experimentation with a prototype of an appropriate resource information system that improves decision making processes in farm management The system includes a geographic information system with a powerful process model that forms a decision support system for land use planning, monitoring and evaluation at farm enterprise level. The land use planning sub-system uses a new concept and supports planning at tactical and operational levels. It consists of a crop growth simulation model that accurately estimates the productivity of each feasible land use, a linear programming model that integrates the physical and socioeconomic information and designs the best suitable plan that maximizes the profit of the system under a given set of constraints (tactical plan), ad a spatial decision model that translates the tactical plan into an actual operational plan. The system illustrates the importance of process models in the integration of information from various disciplines and sources into management decisions, and the application of geographic information systems in support of multiple objective decision problems.

    Salinity management in river basins : modelling and management of the salt-affected Jarreh Reservoir (Iran)
    Shiati, K. - \ 1991
    Agricultural University. Promotor(en): W.H. van der Molen; J.H.G. Verhagen. - S.l. : Shiati - 183
    rivieren - waterlopen - kanalen - water - oppervlaktewater - waterverontreiniging - waterkwaliteit - chemische eigenschappen - waterbeheer - bodem - natrium - verbetering - verzilting - modellen - onderzoek - waterwegen - zoutgehalte - stroomgebieden - drainage - iran - rivers - streams - canals - water - surface water - water pollution - water quality - chemical properties - water management - soil - sodium - improvement - salinization - models - research - waterways - salinity - watersheds - drainage - iran

    The sources and origin of salts in the basin of the two salt- affected Shapur and Dalaki rivers (Southern Iran) and the processes involved in salinization have been studied. The extent of water deterioration have been identified by examining spatial changes in the rivers water quality. Among salinity management measures pertaining to water quality, the engineering measures are investigated. It appears that the construction and management of the planned Jarreh Reservoir on the Shapur River is the most feasible one.

    The dynamic reservoir simulation model, - DYRESM (Imberger, et al., 1978, Version 6.4) is adapted to simulate the salinity/temperature distribution, long-term behaviour and response to various management policies in this reservoir. A simplified method to account for the effect of sediment particles on density of inflows and the inflowing processes in mild bed slope reservoirs is introduced. The method applies only to the steady motion of a turbidity current that is neither depositing nor eroding sediments. The vertical propagation of sediment has not been modelled. This applies to those substances (like dissolved salt) that are not reacting physically or (bio)chemically with suspended particles.

    Various management options to minimize the salinity build-up in the reservoir are examined. Among these, the diversion of the most saline part of the summer flows to a point downstream of the last irrigation intakes will result in a significant water quality improvement. At the end of a 5-year simulation, only a weak salinity gradient remains in the reservoir. Based on simulations, using 15 years of data, and the salt balance calculation, the long-term behaviour of the Jarreh Reservoir is studied, It is shown that the salinity in the reservoir is largely determined by annual variabilty in the river discharge.

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