Vulnerabilities to flood hazards among rural households in India

Natural Hazards - Flooding constitutes the most predominant natural disaster in India. The degree and causes of vulnerability to flood risk vary by society, geographical region and over time. The...     

The most temperature-adapted corals have an Achilles' Heel

The corals of the Persian/Arabian Gulf are better adapted to temperature fluctuations than elsewhere in the Indo-Pacific. The Gulf is an extreme marine environment displaying the highest known summer water temperatures for any reef area. The small and shallow sea can be considered a good analogue to future conditions for the rest of the world’s oceans under global warming. The fact that corals can persist in such a demanding environment indicates that they have been able to acclimatize and selectively adapt to elevated temperature. The implication being that colonies elsewhere may be able to follow suit. This in turn provides hope that corals may, given sufficient time, similarly adapt to survive even in an impoverished form, under conditions of acidification-driven lowering of CaCO₃ saturation state, a further consequence of raised atmospheric CO₂. This paper demonstrates, however, that the uniquely adapted corals of the Gulf may, within the next three centuries, be threatened by a chronic habitat shortage brought about by the dissolution of the lithified seabed on which they rely for colonisation. This will occur due to modifications in the chemical composition of the Gulf waters due to climate change.     

Monitoring food web changes in tide-restored salt marshes: A carbon stable isotope approach

Primary producer (angiosperms, macroalgae, submerged aquatic vegetation), suspended particulate matter, andFundulus heteroclitus isotope values (δ¹³C, δ¹⁵N, δ³⁴S) were examined to assess their use as indicators for changes in food web support functions in tidally-restored salt marshes. Study sites, located throughout the southern New England region (USA), ranged fromSpartina alterniflora-dominated reference marshes, marshes under various regimes and histories of tide restoration, and a severely tide-restrictedPhragmites australis marsh.Fundulus δ¹³C values were greater for fish from referenceSpartina marshes than for fish from adjacent tide-restricted or tide-restored marshes where higher percent cover of C₃ plants, lower water column salinities, and more negative dissolved inorganic δ¹³C values were observed. The difference inFundulus δ¹³C values between a tide-restrictedPhragmites marsh and an adjacent referenceSpartina marsh was great compared to the difference between marshes at various stages of tide restoration and their respective reference marshes, suggesting that food web support functions are restored as the degree of tidal restriction is lessened. While a multiple isotopic approach can provide valuable information for determining specific food sources to consumers, this study demonstrates that monitoringFundulus δ¹³C values alone may be useful to evaluate the trajectory of ecological change for marshes undergoing tidal restoration.     

Interaction of corporate and urban systems: accumulation of intangible assets

This study develops a conceptual framework of the relationship between corporate systems and urban systems in the process of intangible asset accumulation and conducts case studies involving two distinctive and contrasting global firms. Intangible assets are important in maintaining the competitive advantage of cities and regions. The accumulation of local intangibles is the result of the evolutionary development of the relationship between the corporate system and the urban system. The results of the study suggest that the intangible assets of firms are critical in ensuring their competitiveness within a knowledge-based information society.     

Straight from the source's mouth: Controls on field-constrained sediment export across the entire active Corinth Rift,central Greece

The volume and grain-size of sediment supplied from catchments fundamentally control basin stratigraphy. Despite their importance, few studies have constrained sediment budgets and grain-size exported into an active rift at the basin scale. Here, we used the Corinth Rift as a natural laboratory to quantify the controls on sediment export within an active rift. In the field, we measured the hydraulic geometries, surface grain-sizes of channel bars and full-weighted grain-size distributions of river sediment at the mouths of 47 catchments draining the rift (constituting 83% of the areal extent). Results show that the sediment grain-size increases westward along the southern coast of the Gulf of Corinth, with the coarse-fraction grain-sizes (84^th percentile of weighted grain-size distribution) ranging from approximately 19 to 91 mm. We find that the median and coarse-fraction of the sieved grain-size distribution are primarily controlled by bedrock lithology, with late Quaternary uplift rates exerting a secondary control. Our results indicate that grain-size export is primarily controlled by the input grain-size within the catchment and subsequent abrasion during fluvial transport, both quantities that are sensitive to catchment lithology. We also demonstrate that the median and coarse-fraction of the grain-size distribution are predominantly transported in bedload; however, typical sand-grade particles are transported as suspended load at bankfull conditions, suggesting disparate source-to-sink transit timescales for sand and gravel. Finally, we derive both a full Holocene sediment budget and a grain-size-specific bedload discharged into the Gulf of Corinth using the grain-size measurements and previously published estimates of sediment fluxes and volumes. Results show that the bedload sediment budget is primarily comprised (~79%) of pebble to cobble grade (0.475–16 cm). Our results suggest that the grain-size of sediment export at the rift scale is particularly sensitive to catchment lithology and fluvial mophodynamics, which complicates our ability to make direct inferences of tectonic and palaeoenvironmental forcing from local stratigraphic characteristics.     

The Montenegro,Yugoslavia, earthquake of April 15, 1979: source orientation and strength

Long-period teleseismic P, S and Rayleigh waves and geologic considerations indicate that the Montenegro earthquake involved thrust faulting on a plane striking nearly parallel to the Adriatic coast and dipping ca. 15° toward the Yugoslav mainland. There is some support from modeling of body waves recorded on long-period WWSSN instruments for a focal depth of 22 km, but the possibility of a multiple source and the difficulty of matching some of the detailed characteristics of the P- and S-wave forms reduce our confidence in the determination of the depth. Fortunately, the source orientation and moment of the event are not sensitive functions of the depth. The long-period (256 s) moment was 4.6 × 10¹⁹ Nm (4.6 × 10²⁶ dyne-cm). The moment obtained by fitting the first cycle of P and S waves recorded on WWSSN long-period instruments is about four times smaller. This increase of moment with period is consistent with spectral estimates of the moment from SH waves recorded at SRO and ASRO stations.     

Efficiency, Equity and Effect: a case study on virtual water consumption characteristics

Scarcity of water is the key factor restricting the growth of social economy.The virtual water theory provides a new way to solve the problem of water scarcity.For this paper,we have calculated the virtual water consumption of each household,grouped by income,of Gansu province for 1992-2005.Then we advanced the indicator of virtual water with per-unit-of-consumption expenditure to analyze the efficiency of virtual water consumption.Additionally,we recurred to the diversity theory advanced by Ulanowicz,which is broadly employed by ecologists and biologists,to analyze the characteristics of virtual water consumption.As a result,the virtual water consumption of each group decreased yearly from 1992 to 2005,on the whole;decreasing proceeded slower during the period of 1992-1997 than during 1998-2005.Per-unit-consumption expenditure of virtual water for each group represents the same characteristics,on the whole,as virtual water consumption.The largest variation of this indicator exists in the group of the lowest income,which ranges from 1.58 to 0.18 m3/Yuan.yr;whereas the least exists in the highest income group,which is 0.58 to 0.07 m3/Yuan.yr.The virtual diversity indicator increased year by year,and the change of this indicator in 1992-1997 was more obvious than in 1998-2005.Finally,from this study we find that,in view of virtual water,we can save water by means of changing consumption patterns and increasing consumption diversity,but without degrading the quality of living and reducing the demands of living.When the problem of water scarcity becomes more and more serious in Gansu of China,this suggestion becomes more and more important.The consumption,the role of guiding production produce,is very important.An unsustainable consumption pattern is the main factor causing the deterioration of the world environment,especially in a developing country.The sustainable consumption is the only way to develop human beings and achieve the economical sustainable economics.     

The carbonate system in hypersaline solutions: dead sea brines

Various investigators reported a decrease in pH as seawater is concentrated. A similar phenomenon was reported for Dead Sea waters which are about ten times more saline than seawater. The reasons for the low pH values of Dead Sea waters (pH 5.9–6.5), which precipitate CaCO₃, were investigated by determining the apparent dissociation constants of carbonic acid in these brines. A new method, based on alkalinity titration and least-squares fitting, was used to estimate the proton activity coefficient (γ_H+) and the first and second dissociation constants of carbonic acid (K₁′, K₂′) in natural and artificial Dead Sea waters. It was found that as the salt content increases, pK′₁ and pK′₂ values progressively decrease whereas γ_H+ sharply increase. At the highest salinity investigated (TDS = 330 gl^?1) γ_H+ pK′₁ and pK′₂ values are 24.5, 5.09 and 6.23, respectively, as compared to about 0.8, 5.9, 9.1 respectively for normal seawater (19‰ chlorinity) at the same temperature (30°C).The implication of the results of this study regarding solubility of CaCO₃ and the general behavior of the carbonate system in hypersaline solutions is discussed.