Diagnostic study and numerical simulation of the Bombay (India) Deluge

Bombay (latitude: 19.1°N, longitude: 72.9°E, altitude: 14 m asl) received unprecedented amount of rainfall, 94.4 cm in 24 h, from 26 to 27 Jul 2005. Observational and model simulation, based on Advanced Regional Prediction System, study of this extreme event is made. The thermodynamical assessment is made using vertical sounding in model simulation. Artificial thermal perturbation is introduced to initiate the instability for generation of vertical convection with assumption that convection is initiated due to the thermal forcings and neglecting the effect of mechanical perturbation (orographic forcings). Model could simulate the thermal nature of the storm as observed. Also, simulation shows the vigorous nature of thunderstorm with heavy downpour at the rate of 10 cm/h, which is close to the observed.     

A geologic study of the Juan del Grijalva landslide,the most important mass movement during the last century in Mexico

On November 4th 2007, along the Grijalva River in the state of Chiapas, Mexico, has occurred one of the largest landslides ever known. This landslide, known as Juan del Grijalva, destroyed the town of the same name, killing 20 people, and moved 55 million cubic meters of rock and debris down slope to completely block the Grijalva River. In order to understand the characteristics and factors that triggered the Juan del Grijalva landslide, geologic studies were conducted at the site. The results indicate that the landslide was composed of a lithologic sequence of thin-bedded shales and thin to medium-thick-bedded sandstones. This was faulted into several blocks dipping in the same sense as the mass movement. The main triggering factor was the increment of the pore pressure into the lithologic unit due to water saturation after 5 days of heavy rain before the incident. According to records from the last century, the Juan del Grijalva mass movement represents one of the largest mass movements recorded all over the world. The risk conditions of the area after the landslide lead to the rapid construction of an artificial channel to drain the accumulating mass of water upstream and therefore prevent a future catastrophic inundation down stream.     

An Equation of State for Hypersaline Water in Great Salt Lake,Utah, USA

Great Salt Lake (GSL) is one of the largest and most saline lakes in the world. In order to accurately model limnological processes in GSL, hydrodynamic calculations require the precise estimation of water density (ρ) under a variety of environmental conditions. An equation of state was developed with water samples collected from GSL to estimate density as a function of salinity and water temperature. The ρ of water samples from the south arm of GSL was measured as a function of temperature ranging from 278 to 323 degrees Kelvin (^oK) and conductivity salinities ranging from 23 to 182 g L⁻¹ using an Anton Paar density meter. These results have been used to develop the following equation of state for GSL (σ = ± 0.32 kg m⁻³):

A decision support system-based procedure for evaluation and monitoring of protected areas sustainability for the Mediterranean region

Despite common acknowledgement of the value of protected areas as instruments in ensuring sustainability, and their promotion for the achievement of policies on halting the loss of biodiversity, there is no common approach today for monitoring and evaluating them. This paper presents a novel integrated nature conservation management procedure developed to monitor and evaluate the sustainability of Mediterranean protected areas. This procedure was successfully implemented and formally evaluated by protected area managers in six Mediterranean countries, results of which are presented here together with an overview of the web-based Decision Support System (DSS) developed to facilitate its wide adoption. The DSS and procedure has been designed and evaluated by managers as a useful tool, which facilitates and provides needed procedural guidance for protected area monitoring whilst minimizing input requirements to do so. The procedure and DSS were developed following a review of existing protected area assessment tools and a detailed primary investigation of the needs and capacity of its intended users. Essentially, the procedure and DSS guides provide the facilities for protected area managers, in following a participatory approach to develop a context-specific sustainability monitoring strategy, for their protected area. Consequently, the procedure is, by design, participatory, context specific, holistic and relevant to protected area management and institutional procedures. The procedure was piloted and formally evaluated in Greece, Italy, Turkey, Egypt, Malta and Cyprus. Feedback collected from the pilot evaluations is also summarised herein.     

Assessment of deforestation,biodiversity loss and the associated factors: case study of Ijesa-Ekiti region of Southwestern Nigeria

Deforestation is driven by a variety of factors, and has resulted in land use changes that threaten biodiversity, water and energy resources. However, lack of reliable data and survey information in Nigeria has made the estimation of the effect of deforestation difficult to establish. Consequently, the extent and rate of deforestation are less well known. The study therefore, examined and analyzed the spatial and temporal patterns of deforestation over the period of 25 years (1978–2003); measured the rates, trends and explained the factors that determined deforestation in Ijesa-Ekiti region of southwestern Nigeria. The major sources of data for the study were satellites images. These were Landsat MSS 1978, with spatial resolution of 80 m, SPOT XS 1986, SPOT XS 1994, with 20 m spatial resolution and NigeriaSat_1 2003, with 32 m spatial resolution. To make them comparable, they were georeferenced to the same coordinates system, filtered, resampled and enhanced for visualization in a GIS environment. Furthermore, Ilesa, Ijebu-Ijesa, Efon-Alaaye, Iloko-Ijesa, Erin-Oke and Erin-Ijesa were identified and selected for ground truthing to validate the tonal values recorded in the images with the features on the ground. The result of ground truthing was combined with visual image interpretation as training sites for supervised classification. Focus Group Discussions were held with people who had lived in the area for over 20 years as a means of eliciting factors of deforestation and the effects on forest biodiversity. The results indicated forest loss of 53,469.23 ha over the period of 25 years at an annual deforestation rate of 7.21, 2.47, and 5.40% per year for 1978–1986, 1986–1994 and 1994–2003, respectively. FGDs with various categories of people in the bigger towns confirmed deforestation in the area and were due to illegal lumbering, intensive agricultural practices and growth of settlements resulted from increase in human population. FGDs also revealed extinction of many forest species in their communities. In conclusion, the study advanced our understanding on techniques of analyzing deforestation using geo-spatial technology. It also generated a synthesis of information on the rates of deforestation and its driving forces, which are a complex mix of anthropogenic factors, the chief of which has been the conversion of forest resources to agricultural land use.     

Study on rain-runoff process in the peripheral mountainous area of the Sichuan Basin

Studies on rain-runoff process in the peripheral mountainous area of the Sichuan Basin, which is regarded as a key ecological shelter, will contribute to flood control and environmental protection for the Upper Yangtze River Basin. In two typical catchments--the Fujiang River Catchment and the Wujiang River Catchment, rainfall simulations have been conducted to study the rain-runoff processes of yellow soil and limestone soil in three types of land use--forestland, farmland and grassland. Results showed that （1） within the same rainfall process, overland flow occurs first on farmland, then on grassland, and finally on forestland; （2） soil surface coverage has a great impact on the occurrence and amount of overland flow. The runoff amount can increase 2-4 times after the coverage is removed; （3） the infiltration before the occurrence of overland flow will decrease because of higher gravel contents of soil, but it takes no effect on infiltration once overland flow becomes stable; （4） the runoff coefficient of the limestone soil forestland is greater than that of the yellow soil forest land, but less than that of the farmland; （5） three empirical infiltration models, including Horton＇ model, Kostiakov＇ model, and modified Kostiakov＇ model, were compared by using the observed results under rainfall simulation. The results showed that the Kostiakov＇ model performed better than both the Horton＇ model and modified Kostiakov model. According to the results of this research, the Kostiakov＇s model can be used to simulate rainfall infiltration when water erosion is modeled in the peripheral mountainous area of the Sichuan Basin.     

On the global stratotype section and point of the Triassic base

A unique succession of volcanogenic deposits with representative paleontological remains characterizing the Permian-Triassic boundary interval in the North Siberian platform and Taimyr is described. The succession is suitable for selecting a standard for the Triassic base in nonmarine deposits. Abundant and diverse fossils occurring in the succession evidence that volcanism responsible for origin of the plateau basalt province in Siberia was not a brief epoch of paroxysmal eruptions, which eliminated everything alive. Throughout the formation history of relevant plateau basalts, the organic world of the plateau and around existed and gradually evolved.     

The posthumous tectonics and mechanism of exhumation of granitic plutons: The case of the Transbaikal region and the Tien Shan

The study of granitic plutons of the Baikal Highland and the Tien Shan has made it possible to establish new features of their posthumous (after incorporation into the consolidated Earth’s crust) structural reworking and to understand the implications of the cataclastic flow for the exhumation of the crystalline basement in the studied regions. It is shown that granitic plutons undergo appreciable structural transformation at the stages of tectonic reactivation that is significantly separated in time from the moment of formation of plutons as geological bodies. The 3D cataclastic deformation is the main mode of structural reworking of granitic plutons, while the cataclastic flow is the main form of their mobility. Newly recognized slice structures characterize the volumetric deformation of granites.     

Feasibility of pre-earthquake strengthening of buildings based on cost-benefit and life-cycle cost analysis, with the aid of fragility curves

There are two fundamental questions this article aims to deal with. First, whether a pre-earthquake strengthening of a large and heterogeneous building stock (the emphasis here is on building types common in S. Europe), is economically feasible or not, and second what is the optimal retrofit level for mitigating the seismic risk. To this purpose contemporary decision making tools, namely cost-benefit and life-cycle cost analyses, are tailored to the needs of the present study, and implemented with the aid of an ad-hoc developed new software application (COBE06). A method for estimating the reduction in structural vulnerability due to retrofit is proposed, as well as a methodology to determine the optimum retrofit level using the fragility curve approach. Finally, the proposed methodology is used in a pilot application that concerns the city of Thessaloniki, and results are drawn for the feasibility of strengthening the reinforced concrete building stock in this city.     

Benthic nutrient fluxes in the intertidal flat within the Changjiang （Yangtze River） Estuary

In an annual cycle from March 2005 to February 2006, benthic nutrient fluxes were measured monthly in the Dongtan intertidal flat within the Changjiang （Yangtze River） Estuary. Except for NH4^＋, there always showed high fluxes from overlying water into sediment for other four nutrients. Sediments in the high and middle marshes, covered with halophyte and consisting of macrofauna, demonstrated more capabilities of assimilating nutrients from overlying water than the low marsh. Sampling seasons and nutrient concentrations in the overlying water could both exert significant effects on these fluxes. Additionally, according to the model provided by previous study, denitrification rates, that utilizing NO3- transported from overlying water （Dw） in Dongtan sediments, were estimated to be from -16 to 193 μmol·h^-1·m^-2 with an average value of 63 μmol·h^-1·m^-2 （n=18）. These estimated values are still underestimates of the in-situ rates owing to the lack of consideration of DN, i.e., denitrification supported by the local NO3^- production via nitrification.