Evaluating the Degradation of Natural Resources in the Mediterranean Environment Using the Water and Land Resources Degradation Index, the Case of Crete Island

Natural resources degradation poses multiple challenges particularly to environmental and economic processes. It is usually difficult to identify the degree of degradation and the critical vulnerability values in the affected systems. Thus, among other tools, indices (composite indicators) may also describe these complex systems or phenomena. In this approach, the Water and Land Resources Degradation Index was applied to the fifth largest Mediterranean island, Crete, for the 1999–2014 period. The Water and Land Resources Degradation Index uses 11 water and soil resources related indicators: Aridity Index, Water Demand, Drought Impacts, Drought Resistance Water Resources Infrastructure, Land Use Intensity, Soil Parent Material, Plant Cover, Rainfall, Slope, and Soil Texture. The aim is to identify the sensitive areas to degradation due to anthropogenic interventions and natural processes, as well as their vulnerability status. The results for Crete Island indicate that prolonged water resources shortages due to low average precipitation values or high water demand (especially in the agricultural sector), may significantly affect Water and Land degradation processes. Hence, Water and Land Resources Degradation Index could serve as an extra tool to assist policymakers to improve their decisions to combat Natural Resources degradation.

Assessment of surface water management institutions: a case of public irrigation schemes in northern Algeria

The pressure on water resources that Algeria encounters is due to the scarcity and the water demand increase by different sectors of activity. This induces managers to reconsider the traditional supply management approach. The new water policies aim to adopt water demand management by improving the efficiency of its use in the agricultural sector, which consumes more than 59% of freshwater withdrawals. Economic, regulatory, and voluntary instruments have been adopted for better governance of water resources. This study aims to (i) define institutional arrangements on the exploitation of surface water in large irrigation schemes in Algeria and (ii) assess the effectiveness of the current water management instruments. Findings from farmers’ and water distribution agencies’ surveys suggest that objectives expected by the application of the different economic instruments are far from being achieved. Moreover, the absence of effective executive agencies for the implementation of regulations suggests that an improvement in the performance of public administration is necessary to achieve better governance of irrigation water in Algeria. At the local level, and despite a lack of farmers’ will to formally engage in a collective of farmers, they organize themselves around informal arrangements to overcome the challenges associated with water scarcity.

Analysis of the Water Demand-Supply Gap and Scarcity Index in Lower Amu Darya River Basin, Central Asia

Lower reaches of the Amu Darya River Basin (LADB) is one of the typical regions which is facing the problem of water shortage in Central Asia. During the past decades, water resources demand far exceeds that supplied by the mainstream of the Amu Darya River, and has resulted in a continuous decrease in the amount of water flowing into the Aral Sea. Clarifying the dynamic relationship between the water supply and demand is important for the optimal allocation and sustainable management of regional water resources. In this study, the relationship and its variations between the water supply and demand in the LADB from the 1970s to 2010s were analyzed by detailed calculation of multi-users water demand and multi-sources water supply, and the water scarcity indices were used for evaluating the status of water resources utilization. The results indicated that (1) during the past 50 years, the average total water supply (TWS) was 271.88 × 108 m3/y, and the average total water demand (TWD) was 467.85 × 108 m3/y; both the volume of water supply and demand was decreased in the LADB, with rates of −1.87 × 108 m3/y and −15.59 × 108 m3/y. (2) percentages of the rainfall in TWS were increased due to the decrease of inflow from the Amu Darya River; percentage of agriculture water demand was increased obviously, from 11.04% in the 1970s to 44.34% in 2010s, and the water demand from ecological sector reduced because of the Aral Sea shrinking. (3) the supply and demand of water resources of the LADB were generally in an unbalanced state, and water demand exceeded water supply except in the 2010s; the water scarcity index decreased from 2.69 to 0.94, indicating the status changed from awful to serious water scarcity. A vulnerable balanced state has been reached in the region, and that water shortages remain serious in the future, which requires special attention to the decision-makers of the authority.

Contribution on the Use of Household Waste as Bio-Admixture

In the civil engineering field, the incorporation of chemical admixtures is now a practical technics' used for improving the properties of concrete, such as improved workability, decreasing the water demand, increasing strength, etc. However, chemical admixtures have some disadvantages such as environmental pollution during both their manufacture and their use, else, there are rare somewhere. Because of this background, bio-admixtures appear principally useful, due to their environmental effect and friendly properties, bio-admixtures are substances obtained from a biodegradable product also resulting from the methanisation. The objective of this research is the valorization of household waste used as a bio-admixture. Moreover studying its effect on cement path workability, start/end of the cement setting.