Climate change-induced hazards and local adaptations in agriculture: a study from Koshi River Basin,Nepal

Natural Hazards - Changes in climate, associated hazards, local adaptations in agriculture, and socioeconomic factors affecting adaptation were investigated using data from a large survey of 2310...     

Empirical assessment of rockfall and debris flow risk along the Karakoram Highway,Pakistan

Natural Hazards - The Karakoram Highway links north Pakistan with southwest China. It passes through unique geomorphological, geological and tectonic setting. This study focused 200-km-long section...     

Spatial assessment of groundwater use potential for irrigation in Teesta Barrage Project in Bangladesh

In Bangladesh, development of the groundwater resource for irrigation is a vital component of the government’s agricultural strategy to attain food self-sufficiency. Amidst reports of falling groundwater levels in many parts of Bangladesh, the potential of groundwater use has been investigated in the Teesta Barrage Project (TBP) in which large-scale groundwater development for dry-season irrigation has taken place in the recent past. Several techniques and tools have been applied such as the combination of analysis of groundwater hydrographs and mathematical modelling to derive key hydrogeological variables, calculation of net irrigation requirement and the use of geographical information systems. The results show that the economically attractive high-yielding variety (HYV) Boro (dry season) rice cultivation during the groundwater irrigation season may not be sustained in large parts of the project area if the current trends in abstraction are continued. However, due to spatial variation in abstraction, nine thanas (sub-districts)—out of a total of 21 in the project area—may still be able to expand groundwater-irrigated cropland and a groundwater-use potential of 40 mm/year may be created if deep-set shallow tubewells are used by the farmers to abstract groundwater. A structured approach, based on zoning of potential areas, is recommended for groundwater development and use.

---

Resumen En Bangladesh, el desarrollo de las aguas subterráneas para riego es un componente vital del la estrategia agrícola del Gobierno para obtener la auto-suficiencia alimentaria. Un informe intermedio evidencia un descenso de los niveles de aguas subterráneas en muchas partes de Bangladesh, el uso potencial de aguas subterránea ha sido investigado en el Proyecto Tessta Barrage (TBP) en el cual ha tenido lugar el desarrollo de las aguas subterráneas a gran escala para el riego en la estación seca en un pasado reciente. Se ha aplicado algunas técnicas y herramientas, como la combinación del análisis de datos gráficos de aguas subterráneas y modelización matemática para obtener variables hidrogeológicas clave, el cálculo de la necesidad neta de riego y el uso de Sistemas de Información Geográfica. El resultado muestra que el cultivo, económicamente atractivo, de arroz HYV Boro (estación seca) durante la estación de riego con aguas subterráneas puede no ser sostenible en gran parte del área del proyecto si continúan las tendencias actuales en las extracciones. Sin embargo, debido a la variación espacial en la extracción, nueve thanas (subdistritos)—de un total de 21 en el área del Proyecto—pueden todavía sufrir un aumento de la tierra cultivable regada con aguas subterráneas y que se puede asumir un uso potencial de agua subterránea de 40 mm/estación si los granjeros utilizan sondeos someros instalados en fosas para la extracción. Se recomienda una aproximación estructurada para el desarrollo y uso de las aguas subterráneas, basada en la zonificación de áreas potenciales.

---

Résumé Au Bangladesh, l’exploitation des ressources en eau souterraines pour l’irrigation est une composante vitale de la stratégie agricole gouvernementale pour atteindre l’auto-suffisance alimentaire. Parmi les baisses de niveaux piézométriques rapportées sur de nombreuses régions du Bangladesh, le potentiel d’utilisation des eaux souterraines a été étudié sur le Projet de Barrage de Teesta (TBP), où, dans un passé récent, les eaux souterraines ont été massivement exploitées pour l’irrigation en saison sèche. De nombreux outils et techniques ont été utilisés, comme l’analyse combinée des chroniques piézométriques et des modèles mathématiques pour dégager les variables hydrogéologiques clés, le calcul des besoins nets pour l’irrigation, et l’utilisation des systèmes d’information géographique. Les résultats démontrent que la culture en saison d’irrigation de la variété de riz HYV Boro (saison sèche), économiquement attrayante, n’est potentiellement pas viable sur de nombreux secteurs de la zone étudiée si les prélèvements perdurent selon la tendance actuelle. Cependant, du fait de la variation spatiale des prélèvements, neuf thanas (sous-districts)—sur un total de 21 sur le secteur d’étude—pourraient encore augmenter les surfaces irriguées, et une disponibilité en eau de 40 mm/saison pourrait être générée si les agriculteurs utilisaient des puits peu profonds pour exploiter les ressources souterraines. Une approche structurée, basée sur le zonage des secteurs potentiels, est recommandée pour l’exploitation et l’utilisation des eaux souterraines.

     

Cosmic energy equation for extended structures and its application to gravitational galaxy clustering

Cosmic energy equation represents the law of conservation of energy in the region expanding with time as the universe expands. It gives the evolution of kinetic and correlation potential energy with time in a cluster expanding as the universe expands. To understand the clustering of galaxies under the influence of gravitational force, cosmic energy equation is of great help. We use cosmic energy equation for extended structures (galaxies with halos) to analyse the gravitational galaxy clustering in different ways. We try to understand the influence of expansion on the clustering by deriving the relation between correlation parameter b _V and scale factor R. We also derive the relation between the peculiar kinetic energy K and correlation parameter to know that when peculiar kinetic energy dominates over the kinetic energy of galaxies due to expansion. Besides, the evolution of specific heat and energy provides the information regarding the different states of clustering.     

Recycling of Coastal Dredged Sediments from the Northern Nile Delta,Egypt, for Heavy Minerals Exploitation

Mineralogical and textural analyses of 45 undisturbed short cores and 80 grab sediment samples, collected from five frequently dredged navigational areas within harbors and water pathways of the Nile delta littoral system, were utilized for evaluation of these sediments as potential source of economic heavy minerals (EHMs). Results of mineralogical characterization indicate that the average total heavy mineral (HM) concentrations are as follows: Abu Qir Bay (1.7%), Rosetta estuary (3.1%), Burullus fishing port (4.5%), Damietta Harbor (2.9%), and El Gamil lagoon inlet (1.9%). Assessment of HM grades indicates predominance of magnetite, ilmenite, hematite, leucoxene, garnet, zircon, and rutile. Results of the feasibility analysis indicate that dredged sediments at these study areas are considered as a potential source of EHMs and economically promising to be mined for HMs. The present study suggests a practical operative plan of two successive phases for HMs recycling: (1) in-situ initial separation of HMs on the dredger deck using wet-gravity spirals, then (2) transportation of the recovered HM concentrates to an onshore processing plant to selectively separate individual HMs via wet and dry magnetic and electrostatic separators. Alternatively, dredged sediments can be directly pumped to a nearby onshore area as stockpile to be recycled afterward in inland processing plant.     

Biosorption of Heavy Metals in Leachate Derived from Gold Mine Tailings Using Aspergillus fumigatus

Leachate derived from bioleaching process contains high amount of metals that must be removed before discharging the water. Aspergillus fumigatus was isolated from a gold mine tailings and its ability to remove of As, Fe, Mn, Pb, and Zn from aqueous solutions and leachate of bioleaching processes was assessed. Batch sorption experiments were carried out to characterize the capability of fungal biomass (FB) and iron coated fungal biomass (ICFB) to remove metal ions in single and multi‐solute systems. The maximum sorption capacity of FB for As(III), As(V), Fe, Mn, Pb, and Zn were 11.2, 8.57, 94.33, 53.47, 43.66, and 70.4 mg/g, respectively, at pH 6. For ICFB, these values were 88.5, 81.3, 98.03, 66.2, 50.25, and 74.07 mg/g. Results showed that only ICFB was found to be more effective in removing metal ions from the leachate. The amount of adsorbed metals from the leachate was 2.88, 21.20, 1.91, 0.1, and 0.08 mg/g for As, Fe, Mn, Zn, and Pb, respectively. The FT‐IR analysis showed involvement of the functional groups of the FB in the metal ions sorption. Scanning electron microscopy revealed that surface morphological changed following metal ions adsorption. The study showed that the indigenous fungus A. fumigatus was able to remove As, Fe, Mn, Pb, and Zn from the leachate of gold mine tailings and therefore the potential for removing metal ions from metal‐bearing leachate.     

Organisation hydrochimique,biologique et sédimentologique d’un lac intracontinental à peuplements lagunaires : la Birket Karoun (Fayoum,Egypte)

Résumé

La Birket Karoun a été étudiée d’un point de vue biogéologique sur une période de 12 mois. Les données ainsi obtenues, ajoutées à celles de la littérature disponible, permettent de présenter les caractéristiques biogéologiques essentielles de ce bassin original.

Le lac n’est alimenté actuellement que par des eaux continentales issues du système nilotique ce qui entraîne des propriétés hydrochimiques assez différentes des corps d’eau paraliques influencés par la mer. Cependant, les caractéristiques hydrologiques, biologiques et sédimen-taires de la Birket Karoun la classent parmi les écosystèmes de type lagunaire. Il est même possible d’y reconnaître une organisation biogéologique zonale très semblable à celle des lagunes, la partie la plus « marine » (ou la moins confinée) se situant à l’opposé de la zone des apports d’eau douce. Une connexion entre le lac et la mer, actuelle ou passée, étant à peu près exclues, il faut admettre que les eaux continentales concentrées peuvent présenter, dans certains cas, des caractéristiques chimiques et biochimiques presque marines vis-à-vis des êtres vivants.

Dans cette optique, la Birket Karoun apparaît comme un modèle actuel susceptible de fournir une alternative à l’hypothèse d’une « Mer Saharienne » pour rendre compte de l’existence des lacs sahariens pleistocènes à faunes fossiles lagunaires.     

Clustering of non-point mass system of galaxies in the expanding Universe

We derive the cosmic energy equation for the non-point mass system of galaxies (galaxies with halos) by using the adiabatic approximation for the growth of gravitational clustering of galaxies in the expanding Universe. The cosmic energy equation so derived represents the general form of conservation of energy for the expanding volume. Using the derived form of cosmic energy equation we try to study the evolution of correlation potential energy of the system. We also try to explore the condition under which the approximation of extensivity may be applied to the infinite gravitating non-point mass system of galaxies.     

Cosmic energy equation and clustering of non-point mass system of galaxies

Cosmic energy equation is an important equation for studying the gravitational galaxy clustering in the expanding universe. We derive the distribution function for fluctuations in particle number by using the cosmic energy equation for extended structures (galaxies with halos). From spatial distribution function, containing particle fluctuations, we derive the velocity distribution function to understand the influence of particle fluctuations on the velocities of galaxies.With the help of cosmic energy equation we try to find out the physical constraints for the application of quasi-equilibrium approximation.     

Livelihood diversification as an adaptation approach to change in the pastoral Hindu-Kush Himalayan region

Migratory livestock raising has been one of the most important livelihood options for people residing in high mountain areas and has made a significant contribution to the economy of the Hindu Kush Himalayan（HKH） region, both in terms of supporting households and in export earnings. However, in recent decades, changes in the socioeconomic situation and increasing climate variability have led to a need to enhance adaptation by building the resilience of local socio-ecological systems, including economic diversification and sustainable management of natural resources. Based on semistructured interviews with pastoral communities in six countries within the pastoral HKH region, this paper discusses the situation, trends and driving forces behind the diversification of pastoral livelihood. For internal diversification the study highlights the need for enhancement of pastoral livelihoods through value-adding activities in the pastoral sectors. For external diversification changes on policy changes are needed to support free out-migration, market exploitation, and multiple resource use. Finally the paper highlights the role of education in determining household adaptation strategies in the face of various socio-ecological pressures and recommends integrating innovative and indigenous knowledge to develop appropriate methods for risk management and resource management in the pastoral HKH region.