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Located in the hyper-arid regions of Algeria, the M'zab Wadi basin has historically experienced severe flash flooding, causing severe economic damage and loss of life. Identifying potential flood hazard areas in such an arid environment, challenged by data scarcity, is necessary to forecast flood and to create early warning strategies. The paper aims to map and highlight potential flood hazard areas in the M'zab Wadi basin using geographic information system coupled with the Analytical Hierarchy Process method based on seven related flood hazard factors. The accuracy of the flood hazard map was validated using the Receiver Operating Characteristic based Area Under Curves method. The results show that 3.04% (50.35 km2) and 0.53% (8.74 km2) of the basin area are under high and very high flood vulnerability levels, respectively. The obtained results can offer significant insights to policymakers and decision-makers to make well-informed judgments regarding the effectiveness of flood protective infrastructure/measures. Furthermore, the approach adopted can be advantageous for other regions under similar conditions. [ABSTRACT FROM AUTHOR]

We study in this paper land degradation processes in arid environments that are leading to a major environmental change. These processes, which are mostly the outcome of gully development, have direct impact on agriculture potential, biomass degradation, and escalating desertification. Three representative sites within the Negev Highland, Israel, are studied by utilizing terrestrial laser scans to gain detailed spatial information, accurate estimations, and concisely document overarching trends. The resulting information allows us to thoroughly characterize and quantify the geomorphic and vegetative changes and to calibrate rates and trends that have only been roughly estimated thus far. The scans, which were taken over a four-year span (2009–2013), cover three different types of hydrological seasons and provide unique insights on development rates and subsequent ramifications. The characteristic progression of natural land degradation in the Negev Highlands and the techniques used to document and analyze it can be extended globally to regions undergoing similar transitions. [ABSTRACT FROM AUTHOR]

This article is a collation and synthesis of the literature review with the focus on the vulnerability of rural women in developing countries to climate change on the one hand and being pro-active in adapting to climate change on the other. The geographic coverage of the literature is global but with specific examples from India. The information presented in this paper is derived from diverse sources including journal articles and thematic books, and indicates severe adverse impacts not only on women's livelihood opportunities but also on exacerbating the workload and fatigue while decreasing their self esteem and forcing them to undertake some high risks and hazardous activities. The literature indicates that poverty, gender inequality, insecure land rights, heavy reliance on agriculture, less access to education and information are among the principal reasons for their vulnerability to climate change. The vulnerability is also confounded by the meager asset base, social marginalization, lack of mobility and exclusion from the decision-making processes in response to a disaster. However, the literature also shows that women are not only the passive victims of climate change but are also pro-active and agents of hope for adaptation to and mitigation of abrupt climate change. They utilize their experience and expertise to reduce the adverse impacts by adopting prudent strategies. They are also concerned about environmental issues, and are highly supportive of policies regarding environmental restoration. Large knowledge gaps exist regarding the vulnerability of women to changing and uncertain climate especially in arid regions. Authors of this article suggest some action plans and strategies to minimize vulnerability to climate change such as empowering women economically and educationally, organizing training and outreach programmes, and involving them in formal climate change mitigation and adaptation policies and programmes. Authors also outline research needed in order to identify and implement strategies regarding climate change. Collective and continuous efforts are critical to finding the sustainable solutions for this global phenomenon which is adversely impacting the most vulnerable but critically important members of the society. [ABSTRACT FROM AUTHOR]

Previous studies have shown that adaptation to drought in Brazilian Caatinga trees may involve different physiological and morphological strategies. Particular climatic and soil characteristics occur along this dry ecosystem leading to non-homogeneous water availability. Therefore, in certain niches, some species predominate over others, indicating that best performance of a species is not widespread. We studied changes in initial growth, which is the most critical factor during the life of a plant, of two common species of Caatinga (Erythrina velutina Willd. and Enterolobium contortisiliquum (Vell.) Morong) with variable occurrence through the ecosystem. Young plants were subjected to three water regimes: 450 (control), 225 (moderate stress) and 112.5 mm (severe stress) of water spread over 40 days, which represent years with heavy, moderate and scarce rainfall, respectively. Analyses were performed at 20 and 40 days after the initiation of treatments. When compared to the control group, treatments with water restriction reduced the growth of shoots and roots, the number of leaves and leaflets, the total biomass and the leaf area more in E. velutina than in E. contortisiliquum. Taking into account the adaptation of both species in Caatinga, we present evidence of different drought tolerance strategies. The ecological importance of early changes in the growth of species is discussed in the paper. [ABSTRACT FROM AUTHOR]

Abstract: Recent research shows the benefits derived from applying compost and sludge to road embankments to enhance the cover crop and reduce soil loss due to erosion, particularly in arid environments. Following this line of research, the study described in this paper analyzes and compares the use of sludge and compost for the purposes mentioned. In the first phase of this study, compost or sludge was applied separately to road embankments, and in the second phase both were applied simultaneously. This paper discusses the results obtained in each case. Our study was conducted on a total of 32 plots, located along a road embankment. The 32 plots, each with an area of 20m2, were divided into two groups of 16. One group was placed on a 2:1 side slope, and the other was on a 3:2 side slope. Each group received four different compost dosages (0, 40, 60 and 80t/ha) and four sludge dosages (0, 60, 80 and 100t/ha). Four plant species were selected to be planted in each plot. Our study analyzes the survival rate of the plants, their growth rate and germination, colonization of the plots by other species, cover crop per plot, and soil loss, all in relation to the compost and sludge dosage as well as the side slope type. The results obtained show that when only sludge or compost was applied to the plot, soil loss was reduced by an average of 35%, whereas when a mixture of sludge and compost was applied, soil erosion was reduced by 63% to as much as 90%. [Copyright &y& Elsevier]

This paper analyzed the physico-chemical characteristics of natural waters in a drainage system of the Jungar Basin, northwestern China to identify chemical evolution and recharge mechanisms of natural waters in an arid environment. The waters studied are different in mineralization, but are typically carbonate rivers and alkaline in nature. No Cl-dominated water type occurs, indicating an early stage of water evolution. Regolith and geomorphological parameters controlling ground-surface temperature may play a large role in the geological evolution of the water. Three main morphological and hydrological units are reflected in water physico-chemistry. Climate influences the salinization of natural waters substantially. Direct recharge from seasonal snow and ice-melt water and infiltration of rain to the ground are significant recharge processes for natural waters, but recharge from potential deep groundwater may be less important. The enrichment of ions in lakes has been mainly caused by evaporation rather than through the quality change of the recharged water. [ABSTRACT FROM AUTHOR]

Abstract: China''s Lop Nur is one of the world''s largest playas, and is located in the driest part of Central Asia. Scientific explorations by Chinese and foreign researchers have been continuously conducted there since the mid- to late 1800s, and much progress has been made, but many issues remain hotly debated. Particularly intense debate focuses on the formation, environmental evolution, drying date of the Lop Nur lake, and cause of the helical salt crusts recently revealed by remote-sensing images. In this paper, we review the status of this research to provide insights that can inform studies in other arid zones that resemble the Lop Nur. The Lop Nur depression is a secondary unit of the Tarim Block, controlled by faults and fractures formed by the Himalayan orogeny, but various competing explanations have been proposed for how these geological structures gave rise to the depression. The depression''s formation date also remains unclear. Several boreholes have been created to reconstruct the environmental evolution at different time scales since the Quaternary, and deposition rates of lake sediments, especially since the Late Pleistocene, have averaged less than 1mm annually. The drying date of the Lop Nur lake is also debated. The helical salt crust structures appear to have formed as the lake shrank, but how and when they formed is unclear. Huge potash reserves have been found, and large-scale potash fertilizer production has begun, but the origin of these deposits is debated. Understanding the factors causing environmental evolution in this region is a central issue that will help us to clarify these and other debated issues. [Copyright &y& Elsevier]

This paper reviews recently published literature, most of which was published in Chinese, and searches for regional patterns of Holocene changes useful in depicting global patterns. The Holocene in the Xinjiang region can be divided into three stages: a warming and dry early stage (from 11 ∼ 10 to 8 ∼ 7 ka BP), a warm and wet middle stage (from 8 ∼ 7 to 4.5 ∼ 3 ka BP) and a fluctuating cool and dry late stage (since 4.5 ∼ 3 ka BP). The Holocene in the northern Tibetan Plateau can also be divided into three stages: a warming and wet stage (from 10.5 ∼ 10 to 5 ∼ 4 ka BP), followed by a variable drying and probably warm stage (5 ∼ 4 to 3 ka BP) and ending with a cool and dry stage (since 3 ka BP). In the Inner Mongolian Plateau, the early Holocene (from 10.5 ∼ 9.5 to 8 ∼ 7.5 ka BP) was warming and dry, and a warm and wet climate occurred from 7.5 to 3.5, during which the best time was 6.3–3.8 ka BP; the climate has been variably drying and probably cooling since 3.5 ka BP. In the northwestern part of the Loess Plateau, several Holocene palaeosols have been identified (10–9, 7.5–5, 4–3 and 2.7–2 ka BP) with the 7.5–5 ka BP palaeosol being most strongly expressed. The best-developed palaeosol-equivalent in major valleys is a swamp-wetland facies deposited between 8885 and 3805 14C yr BP under an extremely wet regime. The climate has fluctuated significantly at least three times around a dry and probably cool regime after the swamp-wetland facies-depositional period. Our summary shows that the Holocene Climatic Optimum occurred nearly contemporaneously (8–5 ka BP) at all sites in the Xinjiang region, in the Inner Mongolian Plateau and in the northwestern part of the Loess Plateau. A warming and wet early Holocene (10–8 ka BP) in the northern Tibetan Plateau is most likely related to high effective soil moisture resulting from snow and ice melting. We propose here that the middle Holocene Climatic Optimum (8–5 ka BP) in arid to semi-arid China was primarily a delayed response of the low latitude oceans to high latitude peak insolation (9–8 ka BP). [ABSTRACT FROM AUTHOR]

Abstract: In managing river channels, awareness is increasing to acknowledge spatial patterns of channel adjustments, to adopt a holistic catchment perspective, to progress from hard to softer engineering methods, and to utilize a geomorphological approach. However, specific methods for analyzing urban channels have not been related to a management framework. Using Fountain Hills, AZ, as an example of an urbanizing area, this paper develops a dynamic approach for urban river channels that analyzes variations in channel adjustments in a spatial context. The approach requires methods for delineating the drainage network, for dividing the network into channel segments in the area investigated according to road crossings, and for categorizing and characterizing channel segments. Using stream channel hazards as a basis for characterizing channel segments, together with consideration of community views, this approach provides a potential framework for management as illustrated provisionally by indicating the most significant hazards that require management and then suggesting possible management options. [Copyright &y& Elsevier]