Social vulnerability and the natural and built environment: a model of flood casualties in Texas

Studies on the impacts of hurricanes, tropical storms, and tornados indicate that poor communities of colour suffer disproportionately in human death and injury.(2) Few quantitative studies have been conducted on the degree to which flood events affect socially vulnerable populations. We address this research void by analysing 832 countywide flood events in Texas from 1997-2001. Specifically, we examine whether geographic localities characterised by high percentages of socially vulnerable populations experience significantly more casualties due to flood events, adjusting for characteristics of the natural and built environment. Zero-inflated negative binomial regression models indicate that the odds of a flood casualty increase with the level of precipitation on the day of a flood event, flood duration, property damage caused by the flood, population density, and the presence of socially vulnerable populations. Odds decrease with the number of dams, the level of precipitation on the day before a recorded flood event, and the extent to which localities have enacted flood mitigation strategies. The study concludes with comments on hazard-resilient communities and protection of casualty-prone populations.     

Characterizing agrochemical patterns and effective BMPs for surface waters using mechanistic modeling and GIS

Monitoring programs in the agriculturally intense San Joaquin River Valley of California have periodically found organophosphate (OP) insecticide concentrations, predominantly chlorpyrifos, diazinon and methidathion, at levels high enough to cause mortality for the aquatic invertebrate Ceriodaphnia dubia. These detections are likely the result of off-site movement from treated fields. However, the relative significance and magnitude of off-site transport pathways cannot be readily deduced from monitoring data alone. Therefore, a comprehensive modeling system has been constructed to estimate temporal and spatial pesticide source magnitudes and to follow the pesticide dissipation pathways once in surface water. The USEPA models HSPF and PRZM3 were used for the hydrology and non-point source predictions, respectively. Spray drift was accounted for using the mechanistic model AgDrift. The Orestimba Creek Watershed in the San Joaquin Valley was characterized and used as a typical watershed for this region. Representative transport pathways were ranked and quantified, and numerical implementation of best management practices (BMPs) determined which practice may have the highest likelihood for reducing pesticide loadings. Approximately 85% of the predicted chlorpyrifos mass detected between May 1, 1996, and April 30, 1997 resulted from drift, with the largest contributions coming from walnut orchards immediately adjacent to Orestimba Creek. Various simulated drift mitigation measures suggest chlorpyrifos mass loadings can be decreased by over 90% depending upon the type of mitigation chosen. Imposed drift BMPs should be effective in reducing chlorpyrifos levels found in surface waters of the San Joaquin valley if the Orestimba creek watershed is considered representative of watersheds found in this area of California.     

Determination of heavy metals in bee honey with connected and not connected metal wires using inductively coupled plasma atomic emission spectrometry (ICP–AES)

Two honey samples are taken from two parts of the same honeycomb: one that contacts to the surface of the wire and the other taken from the surface that does not contact the wires. Heavy metal contents of these two samples were determined by inductively coupled plasma atomic emission spectrometry). The Mo, Cd, Cr, Fe, Mn, Ni and Zn contents of the honey in contact with wire is higher when compared to the other. Especially, Fe and Zn contents of honey in contact with wire is much higher than the non-contact one. These values are, respectively, 190.21 and 112.76 ppm. Besides, Ni content of honey in contact with wire is approximately 50% higher.     

Persistence,variance and toxic levels of organochlorine pesticides in fluvial sediments and the role of black carbon in their retention

The present study assesses the persistence and variation of organochlorine pesticides (OCPs) and their regulation by total organic carbon (TOC) and black carbon (BC) in freshwater sediment. Sediment samples from the Yamuna River, a major tributary of the Ganges (one of the most populated and intensively used rivers in Asia), had high levels of Σ₂₀OCPs (21.41 to 139.95 ng g^?1). β-Hexachlorocyclohexane (β-HCH) was the most predominant component. ΣHCH and Σdichloro-diphenyl-trichloroethane (DDT) constituted ~86 % of Σ₂₀OCPs. Isomer ratios indicated fresh usage of lindane, DDT and technical-grade HCH. Toxicological comparison with freshwater sediment quality guidelines showed γ-HCH and DDT at high levels of concern. β-HCH, α-HCH, endrin, heptachlor epoxide, dichloro-diphenyl-dichloroethane (DDD), dichloro-diphenyl-dichloroethylene and chlordane were above some of the guideline levels. TOC and BC had mean concentrations of 1.37?±?0.51 % and 0.46?±?0.23 mg g^?1, respectively. BC constituted 1.25 to 10.56 % of TOC. We observed low to moderate correlations of BC with isomers of HCH, p,p′-DDT and methoxychlor while of TOC with Σ₂₀OCPs, γ-HCH, endosulfan sulfate and methoxychlor. Principal component analysis enabled correlating and clustering of various OCPs, BC and TOC. OCP distribution was related with pH, electrical conductivity, soil moisture and finer fractions of sediment. OCPs with similarity in properties that determine their interactions with carbonaceous components of sediment clustered together. A number of factors may, thus, be involved in the regulation of interactive forces between BC and OCPs. BC in this study may be more important than TOC in the retention of some OCPs into fluvial sediments, thereby reducing their bioavailability. The finding is probably the first of its kind to report and emphasises the role of BC in the persistence of OCPs in fluvial sediments.     

The "cultural filter", human transport of mussel shell, and the applied potential of zooarchaeological data

Large assemblages of animal bones and/or shells from archaeological sites can provide data valuable for modern conservation efforts, e.g., by providing accurate historical baselines for species reintroductions or habitat restoration. Such data are underused by natural scientists, partly due to assumptions that archaeological materials are too biased by prehistoric human actions (the so-called "cultural filter") to accurately reflect past biotic communities. In order to address many paleobiological, archaeological, or applied research questions, data on past species, communities, and populations must first be demonstrated to be representative at the appropriate level. We discuss different ways in which one kind of cultural bias, human transport of specimens, can be tested at different scales, using freshwater mussel shells from prehistoric sites in the Tombigbee River basin of Mississippi and Alabama to show how representativeness of samples can be assessed.     

Application of multiple-population viability analysis to evaluate species recovery alternatives

Population viability analysis (PVA) is a powerful conservation tool, but it remains impractical for many species, particularly species with multiple, broadly distributed populations for which collecting suitable data can be challenging. A recently developed method of multiple-population viability analysis (MPVA), however, addresses many limitations of traditional PVA. We built on previous development of MPVA for Lahontan cutthroat trout (LCT) (Oncorhynchus clarkii henshawi), a species listed under the U.S. Endangered Species Act, that is distributed broadly across habitat fragments in the Great Basin (U.S.A.). We simulated potential management scenarios and assessed their effects on population sizes and extinction risks in 211 streams, where LCT exist or may be reintroduced. Conservation populations (those managed for recovery) tended to have lower extinction risks than nonconservation populations (mean = 19.8% vs. 52.7%), but not always. Active management or reprioritization may be warranted in some cases. Eliminating non-native trout had a strong positive effect on overall carrying capacities for LCT populations but often did not translate into lower extinction risks unless simulations also reduced associated stochasticity (to the mean for populations without non-native trout). Sixty fish or 5–10 fish/km was the minimum reintroduction number and density, respectively, that provided near-maximum reintroduction success. This modeling framework provided crucial insights and empirical justification for conservation planning and specific adaptive management actions for this threatened species. More broadly, MPVA is applicable to a wide range of species exhibiting geographic rarity and limited availability of abundance data and greatly extends the potential use of empirical PVA for conservation assessment and planning.     

Physicochemical properties and mineral contents of seven different date fruit (Phoenix dactylifera L.) varieties growing from Saudi Arabia

The date (Phoenix dactylifera L.) fruits (Soukari, Soulag, Barhi, Khulas, Rozaiz, Soughi and Monaif) were evaluated with respect to some physical and chemical properties. While crude protein contents of fruits change between 1.51 % (Soulag) to 2.41 % (Soughi), crude fibre contents ranged between 1.91 % (Soukari) to 3.90 % (Barhi). Vitamin C contents of date samples changed between 971.82 mg/kg (Soughi) to 1,453.15 mg/kg (Barhi). Antioxidant activity of date fruits ranged from 80.07 IC₅₀ (Soukari) to 81.21 IC₅₀ (Soulag). The highest phenolic content was found in Khulas with a mean value of 198 mg GAE/100 g. Energy values of date fruits ranged from 3,725 kcal/kg (Soulag) to 3,870 kcal/kg (Soukari). Sucrose contents of date fruits changed between 1.02 % (Soulag) to 55.71 % (Soukari). Mineral contents of several date fruits were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Date samples contain potassium at a range between 7,468 mg/kg (Khulas) to 9,619 mg/kg (Soulag). Phosphorus contents of fruits were found between 1,848 mg/kg (Soulag) to 3,066 mg/kg (Rozaiz) and followed by magnesium and calcium. The highest Zn (9.33 mg/kg), Cu (4.27 mg/kg) and Mn (3.26 mg/kg) were found in Rozaiz, Soukari and Barhi samples, respectively.     

Spatial and temporal trends of selected trace elements in liver tissue from polar bears (Ursus maritimus) from Alaska, Canada and Greenland

Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg(2+)-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements.     

Solving the United States National Park overflight controversy

By mid-1990 the National Park Service (NPS) must present to Congress recommendations for managing overflights of at least ten national parks. The authors examine the potential role of formal negotiation in setting overflight policy in these parks by reviewing the overflight controversy at Grand Canyon National Park (GCNP). Regulations controlling overflights of the GCNP are only now being implemented after a 17-year conflict that culminated in a congressionally mandated solution. The authors review this controversy and find that, contrary to common perception, the number of park visitors bothered by overflights is not small but roughly equals the number of airborne visitors (up to 450,000 per year). On the basis of this investigation, the authors determine that formal negotiation would have been an appropriate policy-making process because of the clearly defined and limited number of parties and issues involved. Considering the number of park visitors that will continue to be affected by this issue, the authors conclude that formal negotiations should be considered for overflight problems involving other parks. Such negotiations should be park-specific. Differences in park size, extent of the problem, and parties involved would prohibit park-wide negotiations.This article has been adapted from Tourist Flights over the Grand Canyon: The Potential for Negotiated Solutions to Similar Problems, Analysis and Management, October 30, 1987. The opinions expressed in this article are those of the authors; they are not meant to represent the views of the organizations with which the authors are associated.