Sport and commercial fishing conflicts: A theoretical analysis

A recreational sector is added to a standard commercial fishing optimal control model to identify public decision variables which should be considered when determining optimal population levels and allocating harvestable fish between sport and commercial users. Both linear and nonlinear models are presented. A predator-prey relationship is also considered. Results derived from the models indicate that shortcomings exist with current economic inputs to policy making because of failure to consider relevant bioeconomic relationships. Future research topics to remedy this are discussed.     

Assessment of the efficacy of slow-release formulations of the tribenuron-methyl herbicide in field-grown spring wheat

Environmental Science and Pollution Research - The efficacy of slow-release formulations of tribenuron-methyl (TBM) embedded in the matrix of degradable poly(3-hydroxybutyrate) blended with birch...     

Effectiveness of potassium ferrate (VI) as a green agent in the treatment and disinfection of carwash wastewater

Environmental Science and Pollution Research - Carwash wastewater treatment with potassium ferrate (VI) (K2FeO4) was optimized by response surface methodology. The optimum conditions for chemical...     

A workflow to investigate the impacts of weathered multi-walled carbon nanotubes to the mud snail Lymnaea stagnalis

Environmental Science and Pollution Research - Although the development and application of nanomaterials is a growing industry, little data is available on the ecotoxicological effects on aquatic...     

USING CLIMATE FORECASTS FOR WATER MANAGEMENT: ARIZONA AND THE 1997–1998 EL NIÑO1

ABSTRACT: Unrelenting pressure on limited surface water supplies requires increasingly sophisticated water management approaches. Climate forecasts of seasonal precipitation and temperature are potentially useful, but the operational water management community currently underutilizes them. However, some agencies in Arizona took unprecedented advantage of forecasts for a potentially wet winter during the 1997–1998 El Niño event. This study investigates use of this information through a series of semi‐structured in‐depth interviews with key personnel from agencies responsible for emergency management and water supply; their jurisdictions ranged from urban to rural and local to regional. Interviews investigated information acquisition, interpretation, and incorporation into specific decisions and actions. While unprecedented actions were taken by some water management agencies and no agencies implemented inappropriate measures, some missed opportunities for more effective response, primarily through inaction. This study reveals a variety of technical factors and institutional characteristics affecting forecast use. Study findings emphasize the need for: (a) closer ongoing relationships between forecast producers and users, (b) increased institutional flexibility to exploit the increasing skill of seasonal climate forecasts, (c) demonstration projects of effective forecast use, and (d) a regional forum to facilitate information transfer between the hydro‐climatic research community and operational water managers.     

A Case Study of the Beneficial Reuse of Treated Groundwater

The future disposal of treated groundwater at the former Nebraska Ordnance Plant (NOP) Superfund site has been a topic of interest to the local property owners, the U.S. Army Corps of Engineers, and the local regulatory agencies. The Record of Decision for the site includes the extraction, treatment, and disposal of almost 3,000 gpm of groundwater with an estimated restoration time period exceeding 100 years. Interest from property owners and the Nebraska agency charged with regulating groundwater supply prompted the Corps of Engineers to consider several strategies for beneficially reusing the treated water. Alternatives included the establishment of a rural water district or local distribution system; delivery of the water to the municipal supply system of Lincoln, Nebraska, andsol;or other nearby municipalities; and consideration of innovative remedial technologies to reduce the quantity of treated water requiring disposal. The selected disposal plan consists of providing treated groundwater to interested parties for agricultural use with excess treated groundwater discharged to two streams. Multiple feasibility studies were generated, public input was solicited, and interagency agreements were executed during the course of the project. The remediation project is currently being constructed, and at least one property owner has constructed a new center‐pivot irrigation system to use the treated groundwater. © 2001 John Wiley & Sons.     

Reestablishing Naturally Functioning Dunes on Developed Coasts

Common beach management practices reduce the ecological values of coastal dunes. Mechanical beach cleaning eliminates incipient dunes, habitat for nesting birds, seed sources for pioneer dune colonizers and food for fauna, and artificially small, stabilized foredunes reduce the variability in microenvironments necessary for biodiversity. Recent initiatives for reducing coastal hazards, protecting nesting birds, and encouraging nature-based tourism provide incentive for the development of a restoration program for beaches and dunes that is compatible with human use. Suggested changes in management practice include restricting or rerouting pedestrian traffic, altering beach-cleaning procedures, using symbolic fences to allow for aeolian transport while preventing trampling of dunes, and eliminating or severely restricting exotic species. Landforms will be more natural in function and appearance but will be more dynamic, smaller and in a different position from those in natural areas. Research needs are specified for ecological, geomorphological, and attitudinal studies to support and inform restoration planning.     

RESOLUTION OF ENDANGERED SPECIES ACT ISSUES IN PERMITTING TILE PLATEAU CREEK PIPELINE1

ABSTRACT: This paper describes how a hydrologic model proved to be a valuable tool to help interested parties understand impacts to four threatened and endangered fish species in the Upper Colorado River. In 1994, the Ute Water Conservancy District initiated permitting and design of the Plateau Creek pipeline replacement. The project was considered a major Federal action and therefore subject to the National Environmental Policy Act. Under Section 7 of the Endangered Species Act, the U.S. Fish and Wildlife Service (USFWS) entered the process to develop a Biological Opinion (BO) and determined that the project could potentially impact the endangered fish in the 15‐mile reach of the Colorado River. The Section 7 consultation was directed by a Core Committee comprised of stakeholders in the Upper Colorado River watershed. Hydrologic modeling became the evaluation tool for comparing flow reductions to USFWS target recovery flows and defining make‐up flow requirements to meet those targets. The Colorado River Recovery Implementation Program was designated to provide the make‐up flows. The USFWS released a final BO in December 1997, approving diversions through 2015. An Environmental Impact Statement for the project was completed and the Record of Decision was issued by the Bureau of Land Management in early 1998.     

EFFECTS OF TOPOGRAPHY AND SOIL PROPERTIES ON RECHARGE AT TWO SITES IN AN AGRICULTURAL FIELD1

ABSTRACT: Field experiments were conducted from 1992 to 1995 to estimate ground water recharge rates at two sites located within a 2.7‐hectare agricultural field. The field lies in a sand plain setting in central Minnesota and is cropped continuously in field corn. The sites are located at a topographically high (upland) site and a topographically low (lowland) site in an effort to quantify the effects of depression focusing of recharge. Three site‐specific methods were used to estimate recharge rates: well hydrograph analysis, chlorofluorocarbon age dating, and an unsaturated zone water balance. All three recharge methods indicated that recharge rates at the lowland site (annual average of all methods of 29 cm) exceeded those at the upland site (annual average of 18 cm). On an annual basis, estimates by the individual methods ranged from 12 to 44 percent of precipitation at the upland site and from 21 to 83 percent at the lowland site. The difference in recharge rates between the sites is primarily attributed to depression focusing of surface water runon at the lowland site. However, two other factors were also important: the presence of thin lamellae at the upland site, and coarser textured soils below a depth of 1.5 m at the lowland site.