نشریه آب و توسعه پایدار
سال هفتم شماره 1 (پیاپی 15، بهار 1399)

Food and water security are one of the most critical subjects in all countries. Water deficiency is turning to a national crisis in Iran, due to climate change and non-optimal management of water resources. Due to the increase in water tensions, the national production will encounter major challenges which will lead to more dependency on importing foodstuff. It is notable that in the future, water deficiency will not be due to water shortage, but could be the consequence of the weakness in the regulations, inappropriate policies, and unplanned use of water resources. Accordingly, water governance in Iran has become a crucial concern in the context of increasing water deficiency, local and border water conflict, and global climate changes. Drying of water basins and the decline of groundwater is the result of the aforementioned regulations. Altogether, in the current situation of Iran, in order to guarantee the production of sustainable food products, considering the worsening state of water shortage, it is necessary to notice good governance, along with the empowerment of indigenous communities and the revival of their knowledge in areas related to the conservation and optimal utilisation of water resources. In this study, while addressing different dimensions of water governance and its role in water and food security, the innovative water governance methods have been described in the field of water security compared to conventional methods of integrated water resources management.

In recent decades, "good governance" has attracted the attention of many scientific communities. Each researcher has defined good governance with different dimensions and goals. Different views on good governance have complicated the explanation of criteria and related indicators. Confusion over the selection of good governance criteria, especially in the field of natural resources, has become a major problem for researchers. The main reason for this challenge is to confront of natural resources with both natural and social dimensions. In fact, the contrast between these two dimensions increases the lack of integration, Disaffiliation of the Stakeholders and the lack of managerial holism in the field of natural resources. In this study, good governance criteria have been summarized through library studies using descriptive-analytical method. Then, good governance criteria in natural resource management have been proposed. Understandably, recognizing, applying and evaluating good governance criteria and indicators will improve the state of natural resource management.

Under water scarcity conditions livestock production, because of its high content virtual water, has been one of the challenging issues in the scientific literature in this regard.A few scientific references believe that forage crops production, because of their high water requirements, make pressure on water resources of scarce-water countries.Other references are on this idea that there is to somehow exaggeration on the high water requirements of the livestock productions.Therefore, in most cases the livestock water productivity(LWP), especially when the protein content and nutritional values of livestock products and other services are considered, is comparable with the water productivity(WP) of agricultural crops. However, similar to the issues of improvement of WP in agriculture, the key point of livestock production from limited water resources is the improvement of LWP.LWP is defined as the ratio of the net benefit obtained from livestock products and other services to the water used for such productions and services. Livestock water productivity does not seek to maximise the number of livestock or the production of animal products and services. Rather, it opens opportunities to produce the same benefits with fewer animals and less demand for agricultural water. This paper reviews different views on livestock production under water scarcity circumstances considering WP and LWP improvement issues.It then deals with the definition and concepts of LWP and its methods of estimation and calculations.The paper provides some apparent values of LWP measured in different studies and elaborates the issues, difficulties, and sources of errors in this regard. Livestock production could be indicative of an efficient or inefficient use of water resources depending to the method of estimates,calculation approach, and or selected scale. Paper concludes that for the required links between livestock production and use of water resources, especially in the mixed livestock-farming systems and in basin-scale are not established well.

The present study is aimed to optimum design the one of the structural methods of flood control (Levees) based on dynamic programming (DP). In order to accelerate computing time, a model was created based on the combination of discrete differential dynamic programming and genetic algorithm (GA-DDDP). The objective function of this model is to minimize the total costs, including the cost of constructing the structure and residual damage cost. For this purpose, the length of the studied river was divided into three reaches and the optimal dimensions of the four sections were obtained as output results. Modeling and running was done by coding in MATLAB software and the results showed that the running time of GA-DDDP combined model is just 11% of the time to running the classic dynamic planning model. Also in this study, the results of the four-section model were compared with the simpler single-section model (equivalent section). The results show that the simplification of model to one section causes the increasing costs to about 20%.

In order to preserve aquifers, their sustainability assessment against current and future stresses is of vital importance. For this purpose, groundwater sustainability indicators are introduced as measurable variables to provide groundwater system information in a comprehensive way. The indicators can be also served as useful tools to assess sustainability of these natural resources. It should be noted that these indicators are applied to identify sustainability over time (exploitation period) and are not designated to resolve the problem. Every sustainability indicator describes a specific aspect of groundwater systems. These indicators assess groundwater resources sustainability, based on the measurable data to provide information on the quantity and quality of the resources (status and current trends), as well as focusing on social (groundwater accessibility, exploitation and utilisation), environmental (vulnerability and pollution), political, economic, and managerial aspects of the resources. The main objective of this paper is to set up a framework to evaluate the sustainability of groundwater resources, in order to ensure the implementation of sustainable groundwater management across the country and to inform the decision and policymakers on the state of sustainability for a specified groundwater resource. In this regard, 21 indicators are presented in the framework of DPSIR in six categories of quantity and quality, environmental, social, economic, and political aspects of groundwater. With the purpose of integrating the indicators to reach the final number of sustainability, the categorical scaling method has been used with a minimum score of zero (least stable) and a maximum score of 100 (maximum sustainability), and each indicator is divided into five categories.

Adaptation to water scarcity is a topic that has received more attention recently by the Ministry of Energy as well as water experts. Providing appropriate solutions and long-term and efficient plans for this issue requires discussion and consensus on the subject. One of the issues that causes consensus to fail in various scientific disciplines is misunderstanding of concepts and la ack of common technical reference. To come up with appropriate solutions to water scarcity, it is necessary to understand both “adaptation” and “Scarcity”. There are various meanings associated with these two terms that need to be examined in relation to each other and avoid the use of them interchangeably by providing the correct definition of these concepts. This article discusses some of these concepts.

Nowadays, due to strict laws to prevent environmental pollution as well as the importance of recycling and reuse of effluent, the use of processes that can treat wastewater with high efficiency has received special attention. One of the biological and widely used mechanism of domestic and industrial sewage treatment is activated sludge which microorganisms break down organic matter in the sewage while consuming oxygen. The advantages of this method are simple design, simple guidance, optimal efficiency in organic matter removal and less sensitivity to seasonal variations in temperature. After demonstrating the proper performance of the activated sludge in the treatment of variety of sewages, various adjustments and changes were made to adapt this process to different requirements. The disadvantages of conventional activated sludge method are the need to relatively high electrical and mechanical equipment, operational problems, the need for relatively high space for the construction of the wastewater treatment plant and low efficiency in the separation of all suspended organic matter. Membrane bioreactor (MBR) is a method to solve the problems of activated sludge especially reducing the steps of the purification process (removal of sedimentation and disinfection) and increasing the efficiency of reducing organic pollutants. Despite the use of an active sludge reactor, the separation of sludge from water is done by a membrane microfiltration system. This system has been highly efficient for domestic and industrial wastewater treatment and has received special attention in recent years.

Nowadays, the problem of water and soil resources pollution is major and influential issue for the healthy living of humans and living things. Nitrate is one of the decentralized sources of environmental pollution in wastewater or agricultural drainage that caused by excessive use of fertilizer. The infiltration and leakage of these waters into surface water and groundwater sources cause to contaminating these waters with nitrate. Nitrate moves easily into the soil profile due to its negative charge and lack of adsorption on the soil surface that cause to contamination on surface and groundwater. Different physical and chemical methods are commonly used to nitrate adsorption from various municipal, industrial and agricultural wastewaters, which are complex and costly on industrial scales. In this research, various methods of nitrate adsorption have been studied and the main focus of the study is on the process of surface adsorption by cheap biochar as an effective process and a suitable method in the final refining of nitrate-contaminated waters.