AN EFFICIENT RESPONSE MATRIX METHOD FOR COUPLING A GROUNDWATER SIMULATOR AND A REGIONAL AGRICULTURAL MANAGEMENT MODEL1

ABSTRACT: By extending the concept of response matrix to consider “active” and “passive” effects, an efficient response matrix method is developed for coupling a groundwater simulator and a regional agricultural management model The method eliminates the need to store all of the recovery information from preceding time periods. Active effects are those which occur during the actual application of a pumping or recharge stress while passive effects represent the recovery of water levels from an initial departure from steady-state conditions at the beginning of a time step. Derivation of the required matrices and a numerical example are presented for the Salinas Valley groundwater basin in California.     

Injury prevention in natural disasters. A theoretical framework

A theoretical framework for conceptualizing injury patterns in natural disasters is described. In this conceptual framework, natural disasters are divided chronologically into predisaster, disaster and postdisaster phases. Within each phase, four factors (human, engineering/technological, physical environmental and socioeconomic) are identified that play an important role in the causation of injury. By combining these phases and factors into a three by four matrix, one may begin to identify points in the natural history or evolution of a disaster that may be amenable to therapeutic or preventive intervention. The application of this proposed three-phase matrix model to a disaster will permit researchers to reduce a large, complex problem into more manageable, conceptually simpler parts. It may also be of value to disaster planners by suggesting preventive and mitigation measures, as well as aiding in the setting of priorities so that scarce resources can be allocated to achieve maximum reduction of injuries.     

An Index and Model of Human Response to Air Quality

This study undertook an empirical Investigation of human response to air quality. Home interviews of 475 respondents living in 22 neighborhoods of Los Angeles County had elicited information on respondent socioeconomic characteristics, behavioral patterns, and measures of human response to air quality. This data base was then augmented with nine measures of actual air quality for six time frames for each neighborhood.

An observer-based air quality index (OBAQI) was constructed based upon which combination of air quality variables correlated best with the percentage of neighborhood respondents who perceived “smoggy air.” The best combination (OBAQI 3) consisted of prevailing visibility, O₃, and SO₂, each measured as the annual number of days that a selected standard had been equalled or exceeded. Subsequently, multiple regression models were constructed using this index as a predictor of aggregated perception of air quality. In addition to a general model for all neighborhoods, separate models were constructed for clusters of neighborhoods of similar micrometeorology as approximated by uniform elevations and/or coastal distances. Zones of homogeneous air quality and micrometeorology were then defined. Within these zones variation in four measures of human response to air quality was associated with respondent socioeconomic characteristics and behavioral patterns. Both the index and model could prove useful in gauging public response to proposed actions of air quality management districts.     

Impact of soil amendments on metribuzin and DCPA half-lives and mobility into agricultural runoff water

The retention and behavior of two herbicides, metribuzin [4-amino-6-tert-butyl-4, 5-dihydro-3-methylthio-1, 2, 4-triazin-5-one] and DCPA [1, 4-Benzenedicarboxylic acid, 2, 3, 5, 6-tetrachloro-, dimethyl] ester, in runoff and seepage water from agricultural fields were investigated. The objectives of this investigation were to: (i) determine the dissipation and half-life (T _1/2) of metribuzin and DCPA herbicides in soil under three management practices: chicken manure (CM), sewage sludge (SS), and no-mulch native soil (NM); (ii) monitor herbicides residues in runoff and infiltration water following addition of soil amendments; and (iii) determine the impact of soil amendments on the transport of NO₃, NH₄, and PO₄ from soil into surface and subsurface water. Half-life (T _1/2) values of metribuzin were 24, 18, and 12 d in CM, SS, and NM treatments, respectively. Similarly, T _1/2 values of DCPA were greater in CM and SS incorporated soil (45.8 and 52.2 d, respectively) compared to NM native soil (26.2 d). Addition of CM and SS to native agricultural soil increased water infiltration, lowering runoff water volume and herbicide residues in runoff following natural rainfall events. We concluded that soil amendments could be used to intercept pesticide-contaminated runoff from agricultural fields. This practice might provide a potential solution to pesticide contamination of surface and seepage water from farmlands.     

Optimal management of strategic reserves of nonrenewable natural resources

This paper studies the stockpiling issue for an oil importing country that is likely to suffer embargoes, the occurrence and duration of which are uncertain. I show the existence of a decreasing reserves path that the country wants to attain in order to hedge against these disruptions. Allowing the importing country to invest in R&D in order to free itself from the embargo threat, I determine the optimal effort that should be engaged in research. The incentive to develop a backstop is shown to increase with the depletion of the reserves.     

Enhancing Conservation,Ecosystem Services,and Local Livelihoods through a Wildlife Premium Mechanism

We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance‐based payment scheme would allow stakeholders in lower‐income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co‐occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long‐term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here. Mejora de la Conservación, Servicios del Ecosistema y Calidad de Vida Local Mediante un Mecanismo de Compensación de Vida Silvestre     

Ochratoxin A and Penicillic acid interaction in mice

Abstract

Penicillic Acid (PA) and Ochratoxin A (OA) are toxic fungal metabolites that are synergistic in combination. This interaction was investigated using mice which were dosed orally as follows: control, none; solvent control, 0.2 ml bicarbonate buffer; PA, 40 mg/kg; OA, 10 mg/kg and combination, 40 mg/kg PA + 10 mg/kg OA. The only significant histopathologic change observed was an acute multifocal toxic tubular nephrosis which appeared most severe in the combination‐treated mice killed on day 10. While the combination group had a death rate of 20% (5/25), no deaths occurred in the other treatment groups. The increased death rate and the extensive nephrotoxic findings in the combination group indicate a toxic interaction between OA and PA at sub‐lethal dose levels and is consistent with a renal site of action.     

Utilizing a 'systems' approach to improve the management of waste from healthcare facilities: best practice case studies from England and Wales.

Changes in environmental legislation and standards governing healthcare waste, such as the Hazardous Waste Regulations are expected to have a significant impact on healthcare waste quantities and costs in England and Wales. This paper presents findings from two award winning case study organizations, the Cardiff and Vale NHS Trust and the Cornwall NHS Trust on 'systems' they have employed for minimizing waste. The results suggest the need for the development and implementation of a holistic range of systems in order to develop best practice, including waste minimization strategies, key performance indicators, and staff training and awareness. The implications for the sharing of best practice from the two case studies are also discussed.     

Evaluation of the QUIC-URB fast response urban wind model for a cubical building array and wide building street canyon

This paper describes the QUIC-URB fast response urban wind modeling tool and evaluates it against wind tunnel data for a 7 × 11 cubical building array and wide building street canyon. QUIC-URB is based on the Röckle diagnostic wind modeling strategy that rapidly produces spatially resolved wind fields in urban areas and can be used to drive urban dispersion models. Röckle-type models do not solve transport equations for momentum or energy; rather, they rely heavily on empirical parameterizations and mass conservation. In the model-experiment comparisons, we test two empirical building flow parameterizations within the QUIC-URB model: our implementation of the standard Röckle (SR) algorithms and a set of modified Röckle (MR) algorithms. The MR model attempts to build on the strengths of the SR model and introduces additional physically based, but simple parameterizations that significantly improve the results in most regions of the flow for both test cases. The MR model produces vortices in front of buildings, on rooftops and within street canyons that have velocities that compare much more favorably to the experimental results. We expect that these improvements in the wind field will result in improved dispersion calculations in built environments.     

Antibiotika als Umweltkontaminanten — Effekte auf Bodenbakterien

Goal and scope

Among the human and veterinary pharmaceuticals, antibiotics form an important group. Recent research addressed the environmental ‘side effects’ of antibiotics. Evidence for environmental effects of antibiotics has for example been found for the respiratory activity of soil microorganisms. In the present contribution, results of studies on the ecotoxicology of antibiotics that are based on the utilization of carbon substrates in so-called Biolog plates are summarized.

Methods, Results and Conclusions

The method of pollution-induced community tolerance (PICT) takes centre stage. PICT is based on the changes in community composition of environmental communities brought about by a toxicant, which lead to an overall increase in community tolerance to this toxicant. The suitability of such an increase in community tolerance as ecotoxicological endpoint had been the subject of several experiments. It was shown that effect testing of antibiotics requires supplementation of the communities with nutrients, and that the PICT method reveals antibiotic effects with a high specificity. In an application of PICT, effects of three classes of antibacterial compounds were investigated. Dose-response relationships were obtained for all substances, and effect concentrations were partly in the range of expected environmental concentrations. The possible risks of antibiotic use for an increase in the occurrence of antibiotic resistance genes in the environment are also touched upon, including the extent of natural resistance.

Outlook

Due to its specificity, the PICT method has shown to be a suitable ecotoxicological assay. Due to possible effects of tetracyclines on the structure of the soil microbial community, it is advised to use veterinary antibiotics with caution. The risks of an increase in the occurrence of antibiotic resistance in the environment should be investigated in more detail.