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Louhaichi M.,Economic and Policy Research Program SEPRP | Louhaichi M.,Oregon State University | Hassan S.,Economic and Policy Research Program SEPRP | Clifton K.,Economic and Policy Research Program SEPRP | Johnson D.E.,Oregon State University
Agroforestry Systems | Year: 2017

Despite the importance of fodder shrubs to small ruminant diets and production in arid and semi-arid ecosystems, they are often not considered when quantifying grazing land potential. This oversight is mainly due to the time consuming and costly traditional techniques used to estimate shrub biomass. The shrub fodder component should be measured to avoid underestimation of the carrying capacity of rangelands. In this study, we present a fast, reliable and non-destructive method to estimate canopy vegetation cover to obtain aboveground shrub biomass. The experiment was conducted under field conditions in northwest Syria, where seedlings of seven shrub species were monitored for one year: Atriplex leucoclada (Moq.) Boiss., A. halimus L., A. lentiformis (Torr.) S. Watson, A. canescens (Pursh) Nutt., A. nummularia Lindl., Salsola vermiculata L. and Haloxylon aphyllum (C.A. Meyer) Bunge. The experimental layout was a randomized complete block design with five replications. We explored the effectiveness of digital vegetation charting technique (DVCT) for estimating shrub canopy cover. Aboveground shrub biomass was clipped to estimate the dry matter (DM) weight per species and to determine its relationship to canopy cover. In this study, an estimate of greenness (percent green vegetation cover) was extracted by way of greenness algorithms. Simple linear regressions between vegetation cover and biomass for 210 plots were performed. The cover of the seven species differed (P < 0.01): A. leucoclada had the highest vegetation cover (56%) and H. aphyllum the lowest (7%). Vegetation cover and DM biomass were positively correlated (P < 0.01) with R-squared ranging from 0.66 (H. aphyllum) to 0.84 (S. vermiculata). Our method provided reasonable estimations of canopy coverage which could predict aboveground phytomass. We conclude that DVCT offers a rapid, reliable and consistent measurement of shrub cover and biomass provided that shrubs have open architecture. This study shows the potential of digital cameras and image processing to determine cover/biomass in a non-destructive, timely and cost efficient way. © 2017 The Author(s)


Aw-Hassan A.,Economic and Policy Research Program SEPRP | Rida F.,International Center for Agricultural Research in the Dry Areas | Telleria R.,Economic and Policy Research Program SEPRP | Bruggeman A.,The Cyprus Institute
Journal of Hydrology | Year: 2014

During the last three decades, the expansion of irrigation using both surface water and groundwater resources has had an important positive impact on Syria's agricultural production. It is an example of success in achieving food policy objectives, but it has also introduced the challenge of groundwater sustainability. This paper examines the trends in groundwater abstraction for irrigation and the effect of government policies, including input subsidies - such as the diesel fuel subsidy and the crop procurement price support. The fuel subsidy is an important driving force in groundwater depletion and over-abstraction. This analysis examines the interaction between policy signals and the use and allocation of water by farmers. The rapid decline in groundwater resources shows the limitations of this agricultural development strategy and questions its sustainability unless policies change and the rate of abstraction is changed so as not exceed the recharge rate. © 2014 The Authors.


Closset M.,Economic and Policy Research Program SEPRP | Dhehibi B.B.B.,Economic and Policy Research Program SEPRP | Aw-Hassan A.,Economic and Policy Research Program SEPRP
Climate and Development | Year: 2014

We apply the Ricardian approach to analyse the economic impact of climate change on agriculture using the 2007 World Bank Tajikistan Living Standards Survey. The study analyses data of 2557 farm households in 166 villages across the 10 agro-ecological country zones. In general, the results indicated that increasing temperature and precipitation will both be damaging to Tajikistan agriculture and consequently to the net revenue (NR) of farmers in the medium and long term. Regressing NR on climate parameters, household and soil variables showed that these variables have a significant impact on the farmers' NR per hectare. We examined the impact of the current climate on farmers' NR per hectare, and how that is affected by future climate scenarios: one +2.9°C warming and one 4.6°C warming scenarios. Although the analysis did not incorporate variables such as the carbon fertilization effect, the role of technology or the change in prices in the future, significant information for policy-making can be extracted. Tajikistan has very diverse regions in terms of geography, population density and socio-economic situation; our results will help policy-makers to anticipate the adaptation effort needed in different locations of the country. © 2014 Taylor & Francis


Yigezu Y.A.,Economic and Policy Research Program SEPRP | Aw-Hassan A.,Economic and Policy Research Program SEPRP | Shideed K.,Economic and Policy Research Program SEPRP | Sommer R.,International Center for Tropical Agriculture | El-Shater T.,Economic and Policy Research Program SEPRP
Water Policy | Year: 2014

Participants at the international conference on policies for water and food security in the dry areas, held in June 2013, agreed that, given the fast pace of depletion of groundwater, the issue of water valuation in the dry areas is no longer one of whether or not, but rather of how. Policies that have been or are perceived to have adverse effects on the cost of agricultural production or food prices in the dry areas are often not well received and have historically led to popular uprisings. As a result, despite clear evidence of misuse of irrigation water by many farmers, governments have been avoiding the idea of water pricing. This government stance is mainly based on the assumption that policies that aim at valuing water will necessarily affect farmers negatively. Using a case study from Syria and applying a simple optimization model, this paper provides empirical evidence that a policy which introduces a penalty for excessive application of irrigation water would compel farmers to adopt water saving technologies. By so doing, the policy will not only lead to groundwater conservation but also to Pareto-optimal distribution of benefits (i.e., a situation where nobody loses and at best some or all gain). © 2014 IWA Publishing.

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