The application of spatial‐perceptual wilderness mapping to protected areas management in New Zealand

The paper examines the application of a spatial‐perceptual approach to the wilderness management issue of preserving natural ecological processes while also permitting appropriate wilderness use in protected areas. An approach to delimit the spatial extent of multiple perceptions of wilderness held by backcountry users is used—the wilderness perception mapping (WPM) methodology. The results obtained from employing the WPM.methodology are considered for the North West Nelson region of New Zealand. The map product provides new and useful information that has applicability to protected areas management. The role of WPM is discussed with reference to wilderness management in North West Nelson and New Zealand, and to protected areas management in general. The study demonstrates how a technology can be combined with a critical and sensible analysis of needs and procedures to give useful results, and highlights the value of applied interdisciplinary research.     

Backfilling canals to mitigate Wetland dredging in Louisiana coastal marshes

Returning canal spoil banks into canals, or backfilling, is used in Louisiana marshes to mitigate damage caused by dredging for oil and gas extraction. We evaluated 33 canals backfilled through July 1984 to assess the success of habitat restoration. We determined restoration success by examining canal depth, vegetation recolonization, and regraded spoil bank soils after backfilling. Restoration success depended on: marsh type, canal location, canal age, marsh soil characteristics, the presence or absence of a plug at the canal mouth, whether mitigation was on- or off-site, and dredge operator performance.Backfilling reduced median canal depth from 2.4 to 1.1 m, restored marsh vegetation on the backfilled spoil bank, but did not restore emergent marsh vegetation in the canal because of the lack of sufficient spoil material to fill the canal and time. Median percentage of cover of marsh vegetation on the canal spoil banks was 51.6%. Median percentage of cover in the canal was 0.7%. The organic matter and water content of spoil bank soils were restored to values intermediate between spoil bank levels and predredging marsh conditions.The average percentage of cover of marsh vegetation on backfilled spoil banks was highest in intermediate marshes (68.6%) and lowest in fresh (34.7%) and salt marshes (33.9%). Average canal depth was greatest in intermediate marshes (1.50 m) and least in fresh marshes (0.85 m). Canals backfilled in the Chenier Plain of western Louisiana were shallower (average depth = 0.61 m) than in the eastern Deltaic Plain (mean depth range = 1.08 to 1.30 m), probably because of differences in sediment type, lower subsidence rate, and lower tidal exchange in the Chenier Plain. Canals backfilled in marshes with more organic soils were deeper, probably as a result of greater loss of spoil volume caused by oxidation of soil organic matter. Canals ten or more years old at the time of backfilling had shallower depths after backfilling. Depths varied widely among canals backfilled within ten years of dredging. Canal size showed no relationship to canal depth or amount of vegetation reestablished. Plugged canals contained more marsh reestablished in the canal and much greater chance of colonization by submerged aquatic vegetation compared with unplugged canals. Dredge operator skill was important in leveling spoil banks to allow vegetation reestablishment. Wide variation in dredge performance led to differing success of vegetation restoration.Complete reestablishment of the vegetation was not a necessary condition for successful restoration. In addition to providing vegetation reestablishment, backfilling canals resulted in shallow water areas with higher habitat value for benthos, fish, and waterfowl than unfilled canals. Spoil bank removal also may help restore water flow patterns over the marsh surface. Increased backfilling for wetland mitigation and restoration is recommended.     

REGIONAL RAINFALL INTENSITY-DURATION-FREQUENCY CURVES FOR PENNSYLVANIA1

ABSTRACT: A statistical analysis of all available continuous hourly and 15-minute duration rainfall records for Pennsylvania was performed to develop an updated procedure to estimate design storms. As a resuit of this study, Pennsylvania was divided into five homogeneous rainfall regions and a set of rainfall intensity-duration curves developed for each region, for return periods of 1 to 100 years and durations ranging from 5 minutes to 24 hours. The PDT-IDF curves were judged to be a better representation of Pennsylvania rainfall than the nationwide TP-40 maps, particularly for storm events of 10-years and lower return periods. The average time distribution of 24-hour storms in Pennsylvania was found to be well represented by the SCS Type II distribution. The Corps of Engineers SPS 24-hour distribution was found to differ appreciably from both the SCS Type H and the Pennsylvania 24-hour storm distribution. For storm durations between 15 and 90 minutes the standard Yarnell intensity-duration curves closely resemble Pennsylvania storm distributions.     

The adequacy of training for EIA in the United States of America

The well-established environmental impact assessment requirements in the United States have given rise to a number of training needs within federal and state agencies. Requirements for training vary for EIA project managers, technical specialists, senior managers and others involved in EIA. Information needs about EIA vary also, but include general awareness, procedural knowledge, substantive methodological knowledge and technical knowledge. While EIA training is provided in short courses, on the job, and in universities there remain deficiencies in the training of specialists, senior managers, and others. Proposals are made here to help overcome these. This paper examines the needs and provisions for training in environmental impact assessment (EIA) in the USA federal system and in the system created by the California Environmental Quality Act. The investigation is based on the very limited literature on training, on responses to letters, on the printed material requested from agencies and, most importantly, on the results of a series of interviews of personnel in various federal agencies at central and regional levels, in California, and elsewhere. A recent report by the Environmental Law Institute (1981) furnished invaluable background information on EIA training in the federal agencies. The list of liaison officers printed by the Council on Environmental Quality (1982a) was used to request interviews and information.     

Ecotoxicological implications of aquatic disposal of coal combustion residues in the United States: a review

We provide an overview of research related to environmental effects of disposal of coal combustion residues (CCR) in sites in the United States. Our focus is on aspects of CCR that have the potential to negatively influence aquatic organisms and thehealth of aquatic ecosystems. We identify major issues of concern, as well as areas in need of further investigation.Intentional or accidental release of CCR into aquatic systemshas generally been associated with deleterious environmental effects. A large number of metals and trace elements are presentin CCR, some of which are rapidly accumulated to high concentrations by aquatic organisms. Moreover, a variety of biological responses have been observed in organisms following exposure to and accumulation of CCR-related contaminants. In some vertebrates and invertebrates, CCR exposure has led to numerous histopathological, behavioral, and physiological (reproductive, energetic, and endocrinological) effects. Fish kills and extirpation of some fish species have been associatedwith CCR release, as have indirect effects on survival and growth of aquatic animals mediated by changes in resource abundance or quality. Recovery of CCR-impacted sites can be extremely slow due to continued cycling of contaminants withinthe system, even in sites that only received CCR effluents forshort periods of time. The literature synthesis reveals important considerations for future investigations of CCR-impacted sites. Many studies have examined biological responses to CCR with respect to Se concentrations and accumulation because of teratogenic andreproductively toxic effects known to be associated with thiselement. However, the complex mixture of metals and traceelements characteristic of CCR suggests that biologicalassessments of many CCR-contaminated habitats should examine avariety of inorganic compounds in sediments, water, and tissuesbefore causation can be linked to individual CCR components. Most evaluations of effects of CCR in aquatic environments havefocused on lentic systems and the populations of animalsoccupying them. Much less is known about CCR effects in loticsystems, in which the contaminants may be transported downstream,diluted or concentrated in downstream areas, and accumulated bymore transient species. Although some research has examinedaccumulation and effects of contaminants on terrestrial and avianspecies that visit CCR-impacted aquatic sites, more extensiveresearch is also needed in this area. Effects in terrestrial orsemiaquatic species range from accumulation and maternal transferof elements to complete recruitment failure, suggesting that CCReffects need to be examined both within and outside of theaquatic habitats into which CCR is released. Requiring specialattention are waterfowl and amphibians that use CCR-contaminatedsites during specific seasons or life stages and are highlydependent on aquatic habitat quality during those periods.Whether accidentally discharged into natural aquatic systems or present in impoundments that attract wildlife, CCR appears topresent significant risks to aquatic and semiaquatic organisms. Effects may be as subtle as changes in physiology or as drasticas extirpation of entire populations. When examined as a whole,research on responses of aquatic organisms to CCR suggests thatreducing the use of disposal methods that include an aquaticslurry phase may alleviate some environmental risks associatedwith the waste products.     

Impervious Surface Area as a Predictor of the Effects of Urbanization on Stream Insect Communities in Maine, U.S.A.

The influence of urbanization on stream insect communities was determined by comparing physical, chemical, and biological characteristics of streams draining 20 catchments with varyinglevels of urban land-cover in Maine (U.S.A). Percent total impervious surface area (PTIA), which was used to quantify urbanland-use, ranged from 1–31% among the study catchments.Taxonomic richness of stream insect communities showed an abruptdecline as PTIA increased above 6%. Streams draining catchmentswith PTIA < 6% had the highest levels of both total insect and EPT (Ephemeroptera + Plecoptera + Trichoptera) taxonomic richness. These streams contained insect communities with a totalrichness averaging 33 taxa in fall and 31 taxa in spring; EPT richness ranged from an average of 15 taxa in fall and 13 taxa inspring. In contrast, none of the streams draining catchments with6–27% PTIA had a total richness > 18 taxa or an EPT richness> 6 taxa. Insect communities in streams with PTIA > 6% were characterized by the absence of pollution-intolerant taxa. The distribution of more pollution-tolerant taxa (e.g.Acerpenna (Ephemeroptera); Paracapnia, Allocapnia (Plecoptera); Optioservus, Stenelmis (Coleoptera); Hydropsyche, Cheumatopsyche (Trichoptera)), however, showed little relation to PTIA. In contrast to the apparent threshold relationship between PTIA and insect taxonomic richness, both habitat qualityand water quality tended to decline as linear functions of PTIA.Our results indicate that, in Maine, an abrupt change in stream insect community structure occurs at a PTIA above a threshold ofapproximately 6% of total catchment area. The measurement of PTIA may provide a valuable tool for predicting thresholds for adverse effects of urbanization on the health of headwater streams in Maine.     

对英国水獭(Lutra lutra)种群生长的长期监测

欧洲水獭自50年代来明显减少,正在从许多河流消失.本研究基于对英国西部3个自然建群的集水区和英国东部2个通过人工投放加速建群的集水区的长期监测(从1977年以来)结果.到2002年,在每条河流至少收集了16年的数据,在每条研究河上设置一系列研究点,记录水獭出现点的百分率、痕迹点的痕迹数,并通过结合以上2个参数计算年种群指数.在一条自然建群的西部河流,头5年水獭种群生长快速增长,接着生长缓慢.但在2个研究开始就已经有水獭的集水区,其生长比较稳定.东部河流水獭建群的速度缓慢,随时间有巨大的波动.年种群生长率约为1%～7%,在早期较高.对水獭的年度监测计划提出了建议.     

Liquid crystallinity of levan/water/starch solutions

Transmitted light measurements performed with a UV-visible spectrophotometer were used to characterize how starch affects the position of boundaries on the phase diagram for dilute aqueous solutions of levan (a branched polymer of fructose). Data were collected in the range 15 to 70°C; the minimum concentrations required for separation of a nematic phase and the minimum concentration required for a fully nematic solution were identified within this range. While hard interactions (repulsion between rod-like molecular segments) dictate the formation of a liquid crystalline phase at and above ambient temperature in the absence of starch, soft interactions become more significant as solutions are cooled toward ambient when starch is present. Small amounts of starch might be used as a filler to modify the mechanical properties (while retaining the process-related benefits) of levan films cast from liquid crystalline solution.     

Cross-taxonomic potential and spatial transferability of an umbrella species index

Validation that conservation of certain species effectively protects a high proportion of co-occurring species is rare. Our previous work has suggested that an umbrella index based on geographic distribution and life history characteristics would maximize the proportion of conspecifics protected per unit area conserved. Using bird and butterfly data from three mountain ranges in the Great Basin, we examined whether umbrella species also would confer protection to species in different taxonomic groups. Further, we addressed the spatial transferability of umbrella species by considering whether species identified as umbrellas in one mountain range would be effective umbrellas in other mountain ranges. Overall, equal proportions of species would be protected using either cross-taxonomic umbrella species or same-taxon umbrella species. Our data suggested that in a given mountain range, umbrella species identified using data from the same mountain range versus a different mountain range would be equally effective. The ability of one set of umbrella species to confer protection to co-occurring species, however, may vary among taxonomic groups and geographic regions.     

Large-Scale Effects of Timber Harvesting on Stream Systems in the Ouachita Mountains, Arkansas, USA

Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected for three years (1990–1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences, year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features. Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect with our sampling design and analyses.