52 research outputs found

    Could payments for environmental services improve rangeland management in Central Asia, West Asia and North Africa?:

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    "Although several institutional and management approaches that address the degradation of the rangelands have been tested in the dry areas of Central and West Asia and North Africa (CWANA), impact has been limited. Nonetheless, the development of National Action Plans to combat desertification highlights the interest of governments to tackle this issue. Payment for Environmental Services (PES) may be a viable policy option, though, to date, most PES programs have focused on the management of different resources (forests, watersheds). The purpose of this paper is to examine whether PES could be a viable option to promote sustainable rangelands management in the dry rangelands of CWANA. Specifically, it focuses on the scientific gaps and knowledge related to the local and global environmental services produced by rangelands and addresses questions related to the beneficiaries of these services. Institutional conditions necessary for the implementation of such schemes are discussed." Authors' AbstractEnvironmental services, Environmental management, Land management, Rangelands, Collective action, Property rights,

    Testing three rainfall interception models and different parameterization methods with data from an open Mediterranean pine forest

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    Various models have been developed to simulate rainfall interception by vegetation but their formulations and applications rely on a number of assumptions and parameter estimation procedures. The aim of this study is to examine the effect of different model assumptions and parameter derivation approaches on the performance of the Rutter, Gash and Liu interception models. The Rutter model, in contrast to the other two daily models, was applied both on an hourly and on a daily basis. Hourly data from a meteorological station, one automatic and 28 manual throughfall gauges from a semi-arid Pinus brutia forest (Cyprus) for the period between 01/Jul/2016 and 31/May/2020 were used for the analysis. We conducted a sensitivity analysis for the assessment of the model parameters and variables: canopy storage capacity (S), canopy cover fraction (c), the ratio of mean wet evaporation rate to mean wet rainfall rate (Ēc/R̄) and potential evaporation (Eo). Three parameter derivation approaches were tested: the widely used regression method and an automatic model parameterization procedure for optimization of S and c and for optimization of S (with c observed). The parameterized models were run with daily meteorological data and compared with long-term weekly throughfall data (2008–2019). The Gash and Liu models showed low sensitivity to Ēc/R̄. Test runs with different combinations of S, c and Ēc/R̄ revealed strong equifinality. The models showed high performance for both calibration and validation periods with Kling–Gupta Efficiency (KGE) above 0.90. Gash and Liu models with the automatic model parameterization procedures resulted in higher KGEs than with the regression method. The interception losses computed from the long-term application of the three models ranged between 18 and 20%. The models were all capable of capturing the inherently variable interception process. However, a representative time series of throughfall measurements is needed to parameterize the models

    Phenology, Morphology and Physiology Responses of Deficit Irrigated ‘Koroneiki’ Olive Trees as Affected by Environmental Conditions and Alternate Bearing

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    Climate change is affecting water resources in the Mediterranean region. In olive orchards, irrigation water use efficiency could be increased by accounting for trees’ alternate bearing behaviour and growth-stage sensitivity to drought. The main objective of this study is to examine olive tree phenology, morphology and physiology in “on” and “off” productive years for the improvement of irrigation scheduling. A regulated (RDI) and a sustained (SDI) deficit irrigation treatment were applied in a ‘Koroneiki’ olive orchard in Cyprus. Flowering occurred on 11 May 2019 and on 27 April 2021, which was caused by the lower temperatures in 2019. The Kc for the irrigation season, computed from daily water balance observations, was 0.37 in 2019 (38% canopy cover) and 0.41 in 2021 (62% canopy cover). Irrigation treatments did not significantly affect plant morphology and stem water potentials. In “on” years, shoot elongation ceased early in the season and stem water potential towards the end of September (−4.0 MPa) was lower than in the “off” year. Stem water potential recovery in the September of the “off” year indicated that irrigation could be less than 35% ETc in early fall. Water savings in RDI were 24–32% in “on” and 48% in “off” years relative to SDI, with no statistically significant effects on olive yield

    A participatory approach for adapting river basins to climate change

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    Climate change is expected to reduce water availability in the Mediterranean region and water management needs to adapt to future conditions. The aims of this study were (1) to develop a participatory approach for identifying and evaluating management options for river basin climate adaptation and (2) to apply and evaluate the approach in four case-study river basins across the Mediterranean. As part of the approach, a diverse group of stakeholders joined a series of workshops and consultations in four river basins located in Cyprus, Slovenia, Spain and Tunisia. In each river basin, stakeholders expressed their views on challenges in their river basins, as well as options to tackle these challenges. We used the information on challenges, as well as the factors contributing to these challenges to develop a fuzzy cognitive map for each basin. These maps were converted into mathematical models and were used to assess the impact of a total of 102 suggested management options for the four river basins. We linked the options and their estimated impacts with a multi-criteria analysis to identify the most preferred options. The approach was positively evaluated by the participating stakeholders and allowed the link of stakeholders' knowledge and perceptions about their river basin with their preferences for options to adapt the management of their river basins to future conditions

    In vivo and in vitro tracking of erosion in biodegradable materials using non-invasive fluorescence imaging

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    Author Manuscript 2012 March 1.The design of erodible biomaterials relies on the ability to program the in vivo retention time, which necessitates real-time monitoring of erosion. However, in vivo performance cannot always be predicted by traditional determination of in vitro erosion[superscript 1, 2] , and standard methods sacrifice samples or animals[superscript 3], preventing sequential measures of the same specimen. We harnessed non-invasive fluorescence imaging to sequentially follow in vivo material-mass loss to model the degradation of materials hydrolytically (PEG:dextran hydrogel) and enzymatically (collagen). Hydrogel erosion rates in vivo and in vitro correlated, enabling the prediction of in vivo erosion of new material formulations from in vitro data. Collagen in vivo erosion was used to infer physiologic in vitro conditions that mimic erosive in vivo environments. This approach enables rapid in vitro screening of materials, and can be extended to simultaneously determine drug release and material erosion from a drug-eluting scaffold, or cell viability and material fate in tissue-engineering formulations.National Institutes of Health (U.S.) (GM/HL 49039)National Institutes of Health (U.S.) (UL1 RR 025758

    Groundwater resources in the Jabal Al Hass region, northwest Syria: an assessment of past use and future potential

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    In many cases, the development of groundwater resources to boost agricultural production in dry areas has led to a continuous decline in groundwater levels; this has called into question the sustainability of such exploitation. In developing countries, limited budgets and scarce hydrological data often do not allow groundwater resources to be assessed through groundwater modeling. A case study is presented of a low-cost water-balance approach to groundwater resource assessments in a 1,550 k

    Schizophrenia-associated somatic copy-number variants from 12,834 cases reveal recurrent NRXN1 and ABCB11 disruptions

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    While germline copy-number variants (CNVs) contribute to schizophrenia (SCZ) risk, the contribution of somatic CNVs (sCNVs)—present in some but not all cells—remains unknown. We identified sCNVs using blood-derived genotype arrays from 12,834 SCZ cases and 11,648 controls, filtering sCNVs at loci recurrently mutated in clonal blood disorders. Likely early-developmental sCNVs were more common in cases (0.91%) than controls (0.51%, p = 2.68e−4), with recurrent somatic deletions of exons 1–5 of the NRXN1 gene in five SCZ cases. Hi-C maps revealed ectopic, allele-specific loops forming between a potential cryptic promoter and non-coding cis-regulatory elements upon 5â€Č deletions in NRXN1. We also observed recurrent intragenic deletions of ABCB11, encoding a transporter implicated in anti-psychotic response, in five treatment-resistant SCZ cases and showed that ABCB11 is specifically enriched in neurons forming mesocortical and mesolimbic dopaminergic projections. Our results indicate potential roles of sCNVs in SCZ risk

    Global Versus Local Water Footprint Assessment: the Case of Cyprus

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    The formulation of appropriate policies towards improving water resource management requires prompt and accurate information on water use. Soil water balance models provide the means to estimate agricultural water use, in the absence of metered data. This paper presents the spatiotemporal model that was used to assess the blue and green water footprint of crop production in Cyprus, for the period 1995-2009. Furthermore, the paper quantifies the difference between the results of this study with the estimates from the advanced global water use assessments of Siebert and Döll (2010) and Mekonnen and Hoekstra (2011) for Cyprus. The results of the local model show that, on average, total agricultural water use in Cyprus was 506 Mm3 /year, of which 63% is attributed to green water and 37% to blue water. Blue water use ranged from 160 Mm3 /year to 214 Mm3 /year, while green water ranged from 169 Mm3 /year to 441 Mm3 /year. The global versus local comparison revealed that the Siebert and Döll (2010) estimates for Cyprus were 72% lower for total green water use and 41% higher for blue water use, for the period 1998-2002. In the case of the Mekonnen and Hoekstra (2011) estimates, the total green water use was identical with the result of the local model, while blue water use was 43% higher in the global model, for the period 1996-2005. The discrepancies between the results of global and local models are attributed to the different input data, modelling assumptions and parameters adopted by each model. From a policy perspective, global models are not particularly useful as they provide average or static results with high uncertainty level related to data limitations. On the other hand, the local model captured the inter-annual effects of climate variability on crop water use and the results provided can potentially guide policy decisions to a sustainable green-blue water use strategy

    21st Century Projections of Extreme Precipitation Indicators for Cyprus

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    According to observational and model-based studies, the eastern Mediterranean region is one of the most prominent climate-change hotspots in the world. The combined effect of warming and drying is expected to augment the regional impacts of global warming. In addition to changes in mean climatic conditions, global warming is likely to induce changes in several aspects of extreme rainfall such as duration and magnitude. In this context, we explore the impact of climate change on precipitation with the use of several indicators. We focus on Cyprus, a water-stressed island located in the eastern Mediterranean Basin. Our results are derived from a new high-resolution simulation for the 21st century, which is driven by a “business-as-usual” scenario. In addition to a strong temperature increase (up to 4.1 °C), our analysis highlights that, on average for the island, most extreme precipitation indicators decrease, suggesting a transition to much drier conditions. The absolute daily rainfall maxima exhibit strong local variability, indicating the need for high resolution simulations to understand the potential impacts on future flooding
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