Long-distance GM pollen movement of creeping bentgrass using modeled wind trajectory analysis.

The importance of understanding the role of atmospheric conditions in pollen dispersal has grown in recent years with increased field-testing of genetically modified (GM) crop plants. An atmospheric model was used to characterize wind trajectories at 10 m and 100 m above GM pollen source fields located within a 4452-ha "control" area north of Madras, Oregon, USA, designated by the Oregon Department of Agriculture (ODA). The area was used in 2003 for the growth of GM creeping bentgrass (Agrostis stolonifera) engineered to be resistant to glyphosate herbicide. The presence of the GM gene (CP4 EPSPS) provided a distinct selectable marker for pollen-mediated gene flow to sentinel and resident Agrostis spp. plants. Linkage of GM gene presence with wind flow characteristics over the "control" area became essential to understand the timing and processes leading to long-distance transport of this pollen. Wind trajectories showed a general pattern of northwest to southeast air movement. Trajectory travel distances calculated hourly from 06:00 hours to 15:00 hours during the 2003 pollination period (15 June-15 July) showed movement up to 15 km from the "control" area's center by the first hour. Maximum travel distances increased to 40 and 55 km after two and three hours from release, respectively. Calculated wind trajectory positions corresponded with observed long-distance pollen-mediated gene flow in the seedlings of sentinel and resident plants. The highest correlations were found during the late morning hours. Back-calculated wind trajectories from sentinel and resident locations with GM-gene-positive progeny suggested that most successful fertilizations occurred in the direction of prevailing winds during late June 2003. The occurrence of positive progeny from sentinel plants, upwind of the "control" area during this period, indicated the additional influence of local topography on pollen dispersal.     

我国环境管理体制问题及其对策探讨

分析和讨论了我国现行环境保护管理体制中主要存在的问题,结合对一些发达国家环境管理发展经验的分析比较,从我国的国情出发,提出了与市场经济新体制相适应的我国环境保护管理体制建设问题的几点建议。     

Use of statistical methods in industrial water pollution control regulations in the United States

This paper describes the process for developing regulations limiting the discharge of pollutants from industrial sources into the waters of the United States. The process includies and surveys of the industry to define products, processes, wastewater sources and characteristics, appropriate subcategorization and control technologies in use. Limitations on the amounts of pollutants that may be discharged in treated wastewater are based on statistical analysis of physical and chemical analytical data characterizing the performance capability of technologies in use in the industry. A general discussion of the statistical approach employed is provided along with some examples based on work performed to support recently promulgated regulations. The determination of regulatory discharge limitations, based on estimates of percentiles of lognormal distributions of measured pollutant concentrations in treated wastewater, is presented. Modifications to account for different averaging periods and detection limit observations are discussed.     

A NUMERICAL ESTUARINE FLOW MODEL1

A novel estuarine flow model is proposed. It provides some two-dimensional features while using an essentially one-dimensional approach. The model is applied to the Upper Delaware Estuary, and is shown to match available field data with acceptable accuracy. The model is shown to be numerically stable and reasonably mass conservative.     

AGRICULTURAL CONSERVATION PROGRAM: AN EVALUATION1

The Agricultural Conservation Program (ACP), is undergoing a new, rigorous evaluation to determine its effectiveness in conserving the Nation's agricultural soils and waters. ACP deals with many types of conservation practices, but the focus here is on the evaluation of soil and water related practices. ACP has depended heavily on the State and private forestry services, Soil Conservation Service, and the Cooperative Extension Services, for technical expertise. Thus, the process is an evaluation of the effectiveness of a “team of agencies,” as well as of the program itself. Results of the evaluation have helped to develop new thrusts which have moved ACP further into the position of treating the total conservation problem. Phase I has its limitations. It did not address the impact of wind erosion, water quality, change in productive capacity, soil quality, wildlife habitat, off site and farm income impacts. It does show that ACP has and is doing a very good job in meeting its stated purposes. It is clear that ACP's effectiveness can be improved with more and better advanced planning and more intensive use of soil maps, the USLE, and other scientific tools. ACP is headed in this direction.     

Using Information on Spatial Variability of Small Estuaries in Designing Large-Scale Estuarine Monitoring Programs

In the early 1990s, EPA's Environmental Monitoring and Assessment Program (EMAP) documented the ecological condition of the overall population of small estuaries along the mid-Atlantic coast of the United States. However, the Program did not provide detailed information on the condition of individual estuaries less than 260 km² in surface area, a group of estuaries of concern to environmental managers. To address the needs of environmental managers, when EMAP returned to the region in summer 1997, it included a study of the spatial variability of ecological indicators within individual small estuaries. At 127 probability-based sites in 10 estuaries, EMAP measured a variety of parameters of water quality and sediments, including dissolved oxygen (DO), nutrients, grain size of sediments, contaminants in sediments, and community structures of benthic macroinvertebrates. From this information the ecological condition (e.g., percent area with DO concentrations below 5mg L^–1) for each estuary, along with 90% confidence interval, was determined. The width of the confidence interval was then recalculated for sample sizes ranging from two stations to the total number of stations sampled in that estuary. Confidence interval widths were then plotted against sample size. These plots can be useful in designing future regional monitoring programs with a goal of describing conditions in individual systems as well as broad geographic regions. Results illustrate that beyond five stations per estuary, the reduction in the width of the confidence interval with increasing sampling intensity is relatively small; however, individual program managers need to determine "how small is small enough."     

Scientific barriers

Whatever the appeal of extreme integrism or holism, science is necessarily more utilist and partial. We can only address our environmental problems scientifically if we identify the most pressing and attack them first. To do so, we must break with the monistic ideals and traditions of both theoretical and mechanistic ecology to pursue particular solutions instead of global models. Statistical analysis of empirically identified patterns has proven effective in providing such solutions, perhaps because empirical patterns are less valueladen than theoretical or mechanistic alternatives or because such patterns are closer to experience and easier to understand. Unfortunately, such simple analyses are often less valued by leading ecologists who seek intellectual content rather than predictive power and practicality. To overcome this barrier to actionable information, the body of scientists must reaffirm their commitment to environmental action through their work as journal referees, grant reviewers, scientific critics and teachers.     

Bioaccumulation of PAHs in the Zebra Mussel at Times Beach, Buffalo, New York

The zebra mussel, Dreissena polymorpha, was utilized in an in situ study in the Times Beach Confined Disposal Facility (CDF) located in Buffalo, New York, Mussels, placed both in the water column (upper position) and at the sediment surface (lower position), survived a 34-day exposure to the CDF. At the CDF, total polycyclic aromatic hydrocarbon (PAH) concentrations in the water column were below detection limits (<0.010 mg 1-1), mean total PAH concentrations in the sediment were 164.41 mg kg-1, and mean total PAH concentrations in mussel tissues after the 34-day exposure were 6.58 mg kg-1. PAH concentrations in mussels exposed for 34 days at the CDP were compared to a baseline PAH concentrations in mussel tissue prior to study initiation (Day 0), and mussel tissue from the reference site (Black Rock Channel Lock). There was a significant increase in total PAHs in mussel tissues over the 34 Day period at the CDF. No significant accumulation occurred at the reference site. PAHs which increased significantly in mussel tissue at the CDF were fluoranthene, pyrene, chrysene, and benzo(a)anthracene. Benzo(a)anthracene concentrations increased significantly in mussels at the upper position overall at Times Beach. Concentrations of Total PAHs, fluoranthene, pyrene, and chrysene were not related to position.     

Designing Environmental Databases for Statistical Analyses

The Environmental Monitoring and Assessment Program (EMAP) collects data that are used to statistically assess the environmental condition of large geographic regions. These data are then posted on the EMAP web site so that anyone can use them. Databases used for the statistical analyses, "analytical" databases, differ in design from the "general-use" databases used by a secondary audience. Their scope is usually restricted in time, in geographic extent, and in type and content of data, often being limited to a single scientific discipline. Their structure may be more horizontal than vertical, so that statistical programs can import the data easily. Their design is strongly influenced by the nature of the scientific analysis because the goal is to create a good computing environment for that analysis. We illustrate these aspects of design with an analytical database for estuaries in the U.S. mid-Atlantic region.