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Since ancient times, dams have been built to store water, control rivers, and irrigate agricultural land to meet human needs. By the end of the 19th century, hydroelectric power stations arose and extended the purposes of dams. Today, dams can be seen as part of the renewable energy supply infrastructure. The word dam comes from French and is defined in dictionaries using words like strange, dike, and obstacle. In other words, a dam is a structure that stores water and directs it to the desired location, with a dam being built in front of river valleys. Dams built on rivers serve various purposes such as the supply of drinking water, agricultural irrigation, flood control, the supply of industrial water, power generation, recreation, the movement control of solids, and fisheries. Dams can also be built in a catchment area to capture and store the rainwater in arid and semi-arid areas. Dams can be built from concrete or natural materials such as earth and rock. There are various types of dams: embankment dams (earth-fill dams, rock-fill dams, and rock-fill dams with concrete faces) and rigid dams (gravity dams, rolled compacted concrete dams, arch dams, and buttress dams). A gravity dam is a straight wall of stone masonry or earthen material that can withstand the full force of the water pressure. In other words, the pressure of the water transfers the vertical compressive forces and horizontal shear forces to the foundations beneath the dam. The strength of a gravity dam ultimately depends on its weight and the strength of its foundations. Most dams built in ancient times were constructed as gravity dams. An arch dam, on the other hand, has a convex curved surface that faces the water. The forces generated by the water pressure are transferred to the sides of the structure by horizontal lines. The horizontal, normal, and shear forces resist the weight at the edges. When viewed in a horizontal section, an arch dam has a curved shape. This type of dam can also resist water pressure due to its particular shape that allows the transfer of the forces generated by the stored water to the rock foundations. This article takes a detailed look at hydraulic engineering in dams over the millennia. Lessons should be learned from the successful and unsuccessful applications and operations of dams. Water resource managers, policymakers, and stakeholders can use these lessons to achieve sustainable development goals in times of climate change and water crisis. [ABSTRACT FROM AUTHOR]

Nitrification inhibitors, such as nitrapyrin (NI), are increasingly co‐applied with nitrogen (N) fertilizers as part of sustainable agricultural practice. Several studies in temperate regions have documented the effectiveness of NI in retaining soil ammonium (NH4+), minimizing N loss and increasing crop yields. However, less is known about the effects of NI in Mediterranean regions, where agricultural production is challenging and requires intensive irrigation and fertilization. We investigated the short‐term impact of the nitrification inhibitor nitrapyrin (2‐chloro‐6‐(trichloromethyl)pyridine) in a two‐factor mesocosm experiment, using a typical Mediterranean soil, where NI was co‐applied with a selection of urea‐based fertilizers: urea (U), U with urease inhibitors (U + UI), methylene urea (MU) and zeolite‐coated urea (ZU). NI co‐applied with urea fertilizers resulted in higher availability of soil NH4+ and a concurrent increase in NH3 volatilization. Net cumulative soil NH4+ availability was 1.5–3.3 fold greater when NI was applied. Concurrently, net cumulative nitrate (NO3−) and nitrite (NO2−) availability was reduced by 10%–60%; this was found for all the tested fertilizer types except MU fertilizer, where the net cumulative soil NO3− and NO2− doubled. Nitrous oxide (N2O) emissions from urea fertilization were reduced by 40% with UI, 50% with NI and 66% with NI + UI. Interestingly, after 28 d, the composition of soil microbial communities was distinctly different, due to NI application. Specifically, NI application dramatically reduced the abundance of ammonia‐oxidizing and denitrifying bacterial functional groups. NI was effective in reducing N2O emissions in this calcareous soil; however, NH3 emissions were remarkably enhanced. These findings have important implications for the large‐scale adoption of inhibitor technologies in Mediterranean agroecosystems and for the reduction of greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Origanum dictamnus L. (Lamiaceae), a local endemic plant of Crete (Greece), creates polysaccharide-containing subcuticular compartments presenting biological activity against phytopathogenic fungi, and, among others, significantly affects the fungal cell wall polysaccharides. This field study introduces a fertilization scheme for O. dictamnus, which was developed and refined to optimize the yield as well as critical herbal quality aspects. Five fertilization schemes were investigated, based on a polysaccharide-based Integrated Nutrient Management (INM), a mixture of conventional inorganic fertilizers (ChF) and two biostimulants (not algae) via foliar and soil application. Plant growth, together with leaf chlorophyll fluorescence and color (SPAD meter, DA meter, Chroma Meter) were determined. The leaf content of chlorophyll, three critical antioxidant compounds (carotenoids, flavonoids, phenols) and nutrients were also assessed. Considering all three antioxidants together, the enhanced efficiency, non-toxic, water-soluble, polysaccharide-based INM by foliar application was the most stimulatory scheme, playing an important role in plant growth and development. The present field study provides, for the first time, baseline fertilization data improving key herbal quality features in O. dictamnus and unravels the attainment of high antioxidant properties. The latter may be exploited in favor of its further utilization as a raw material for tea preparation, medicinal purposes, natural food flavoring and/or food preservative. [ABSTRACT FROM AUTHOR]

This document provides an overview of the complex relationship between climate, water, soil, and other natural resources. It acknowledges that our understanding of climate is still incomplete and that there are challenges in studying and managing climate change. The document highlights the vulnerability of certain regions, such as the Mediterranean basin and Africa, to climate-related phenomena and the need for improved adaptation practices and resource management. It explores specific scientific fields related to climate change, land use, water availability, and the impact of agronomic practices on greenhouse gas emissions and crop production. The document concludes by discussing knowledge gaps and challenges in the climate-crop-water-soil system, including the growing global population and the unsustainable use of natural resources. It emphasizes the importance of addressing legislation and policy issues to address climate vulnerabilities. [Extracted from the article]

Water tunnels are one of the oldest hydro-technologies for extracting water resources and/or transmitting them through water distribution systems. In the past, human societies have used tunneling for various purposes, including development, as a measure to enable underground resource extraction and the construction of transportation networks in challenging landscapes and topographies. The development of hydro-technology potentially involves the construction of tunnels to feed aqueducts, irrigation and waste water systems. Thus, the ability to make and maintain tunnels became an important component in creating lasting and sustainable water systems, which increased water supply and security, minimized construction costs, and reduced environmental impact. Thus, this review asks how, when and why human societies of the past included tunneling for the development of lasting water supply systems. This review presents a comprehensive overview across time and space, covering the history of tunneling in hydro technology from antiquity to the present, and it ponders how past experiences could impact on future hydro-technological projects involving tunneling. A historical review of tunnel systems enhances our understanding of the potential, performance, challenges, and prospects associated with the use of hydro-techniques. In the past, as the different examples in time and space demonstrate, tunneling was often dedicated to solving local problems of supply and disposal. However, across the world, some features were repeated, including the need for carving through the living rock or digging to create tunnels covered with stone slabs. Also, the world-wide use of extensive and costly tunnel systems indicates the high level of investment which human societies are willing to make for securing control over and with its water resources. This study helps us to gather inspiration from proven technologies of the past and more recent knowledge of water tunnel design and construction. As we face global warming and its derivate problems, including problems of water scarcity and flooding, the ability to create and maintain tunnels remains an important technology for the future. [ABSTRACT FROM AUTHOR]

Wastewater treatment and reuse has passed through different development stages with time. This study reviews the most essential changes in water reclamation and reuses over millennia, focusing on initial approaches in the Hellenic world and discussing the current situation. Based on archeological evidence and time records, the awareness of the Greeks regarding land disposal, irrigation, and water reuse is highlighted. The latter has evolved into a plethora of applications, with Direct Potable Reuse (DPR) representing one of the last modern frontiers. Currently, advances in wastewater treatment and the spreading of wastewater treatment plants producing large amounts of treated effluents increase the potential for water reuse. This is regarded as a critical option for the continuing protection of water resources and human health, while concurrently satisfying water demand, particularly in areas subject to increased water scarcity. The main constraints in the expansion of water reuse practices are discussed, focusing on wastewater treatment efficiency and quality effluent standards issues, as well as on the lack of motivations related to the acceptability of this practice by final users. Against these challenges, the need for a transition from an "issue-by-issue" approach to a broader integrated water management framework is highlighted. [ABSTRACT FROM AUTHOR]

Land application of olive mill wastewater (OMW) is considered a promising low-cost practice for olive-oil producing countries. The objectives of this work were to investigate: (i) OMW treatment potential of a land treatment system (LTS), planted with a E. camaldulensis species, regarding N, P, C, and phenols; (ii) the effects of OMW on chemical properties of soil and soil solution characteristics; and (iii) the performance of E. camaldulensis in terms of biomass production and N and P recovery. E. camaldulensis received OMW for two growing seasons at rates based on maximum organic loading. These rates were almost equivalent to the reference evapotranspiration of the area. Soil solution and soil samples were collected from three different depths (15, 30 and 60 cm) at specified time intervals. - Also, samples of plant tissues were collected at the end of application periods. OMW land application resulted in significant reduction in inorganic and organic constituents of OMW. At 15 cm of soil profile, the average removal of COD, TKN, NH4+-N, TP, In-P, and total phenols approached 93%, 86%, 70%, 86%, 82%, and 85%, respectively, while an increase in soil depth (30 and 60 cm) did not improve significantly treatment efficiency. Furthermore, OMW increased soil organic matter (SOM), total kjeldahl nitrogen (TKN), and available P, particularly in the upper soil layer. In contrast, low inorganic N content was observed in the soil throughout the study period caused probably by increased competition among soil microorganisms induced by the organic substrate supply and high C/N ratio. Also, electrical conductivity (EC) and SAR increased by OMW addition, but at levels that may do not pose severe risk for soil texture. Enhancement of soil fertility due to OMW application sustained eucalyptus trees and provided remarkable biomass yield. In conclusion, land application of OMW has a great potential for organic matter and phenol assimilation and can be effectively used for OMW detoxification. [ABSTRACT FROM AUTHOR]