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631.
A review of wetland impacts authorized under the New Jersey Freshwater Wetlands Protection Act (FWPA) was conducted based on permitting data compiled for the period 1 July 1988 to 31 December 1993. Data regarding the acreage of wetlands impacted, location of impacts by drainage basin and watershed, and mitigation were analyzed. Wetland impacts authorized and mitigation under New Jersey's program were evaluated and compared with Section 404 information available for New Jersey and other regions of the United States.Under the FWPA, 3003 permits were issued authorizing impacts to 234.76 ha (602.27 acres) of wetlands and waters. Compensatory mitigation requirements for impacts associated with individual permits required the creation of 69.20 ha. (171.00 acres), and restoration of 16.49 ha (40.75 acres) of wetlands. Cumulative impacts by watershed were directly related to levels of development and population growth.The FWPA has resulted in an estimated 67% reduction [44.32 ha (109.47 acres) vs 136.26 ha (336.56 acres)] in annual wetland and water impacts when compared with Section 404 data for New Jersey. For mitigation, the slight increase in wetland acreage over acreage impacted is largely consistent with Section 404 data.Based on this evaluation, the FWPA has succeeded in reducing the level of wetland impacts in New Jersey. However, despite stringent regulation of activities in and around wetlands, New Jersey continues to experience approximately 32 ha (79 acres) of unmitigated wetland impacts annually. Our results suggest that additional efforts focusing on minimizing wetland impacts and increasing wetlands creation are needed to attain a goal of no net loss of freshwater wetlands. 相似文献
632.
Based on intergroup theory, this study examined relationships among group characteristics (racioethnicity, gender, and level), contextual organizational unit characteristics (gender and racioethnic heterogeneity, resource support for women and racioethnic minorities) and perceptions of diversity climate by faculty at a large university. Compared to white men, white women and racioethnic minorities placed greater value on employer efforts to promote diversity, and held more favorable attitudes about the qualifications of women and racioethnic minorities. The study found that group rather than contextual organizational unit characteristics were more strongly related to diversity climate. However, the organizational unit characteristic, gender heterogeneity, was significantly related to valuing diversity. The greater the ratio of women in a unit, regardless of the respondents' gender, racioethnicity or level, the more favorable diversity activities were viewed. In addition, units whose allocation of resources to racioethnic minorities were perceived as insufficient by respondents were more likely to have members who valued diversity and held favorable perceptions toward the qualifications of racioethnic minorities. Implications for organizations and future research are offered. 相似文献
633.
Watercraft collisions account for 25–30% of manatee deaths annually in Florida. Education and outreach interventions for boaters
are strategies for reducing manatee mortality. We evaluated the effectiveness of the Manatee Watch program by surveying primary
boat users whose boats were approached by Manatee Watch. We compared the attitudes, knowledge, and behavioral intentions of
boaters who received Manatee Watch materials with a control group of boaters observed by the Florida Marine Research Institute
in Tampa Bay during 1999–2001. Results of the 51-item telephone survey with 499 boaters indicated that the Manatee Watch intervention
had little effect on boater’s attitudes, knowledge, and behaviors regarding manatees. However, individual attitude scores
were positively correlated with safe boating behaviors in shallow waters including maintaining a slower speed and watching
out for manatees. Overall knowledge about manatees was correlated with one manatee-safe boating behavior. To improve efficacy,
educators should (a) incorporate evaluation into the planning stages of program development; (b) target messages to influence
boaters’ attitudes toward manatees and ecosystem health, and their feelings of ownership and empowerment; (c) facilitate active
participation of the boaters; and (d) increase the duration and variety of intervention. 相似文献
634.
Laurance WF Nascimento HE Laurance SG Andrade AC Fearnside PM Ribeiro JE Capretz RL 《Ecology》2006,87(2):469-482
The effects of habitat fragmentation on diverse tropical tree communities are poorly understood. Over a 20-year period we monitored the density of 52 tree species in nine predominantly successional genera (Annona, Bellucia, Cecropia, Croton, Goupia, Jacaranda, Miconia, Pourouma, Vismia) in fragmented and continuous Amazonian forests. We also evaluated the relative importance of soil, topographic, forest dynamic, and landscape variables in explaining the abundance and species composition of successional trees. Data were collected within 66 permanent 1-ha plots within a large (approximately 1000 km2) experimental landscape, with forest fragments ranging from 1 to 100 ha in area. Prior to forest fragmentation, successional trees were uncommon, typically comprising 2-3% of all trees (> or =10 cm diameter at breast height [1.3 m above the ground surface]) in each plot. Following fragmentation, the density and basal area of successional trees increased rapidly. By 13-17 years after fragmentation, successional trees had tripled in abundance in fragment and edge plots and constituted more than a quarter of all trees in some plots. Fragment age had strong, positive effects on the density and basal area of successional trees, with no indication of a plateau in these variables, suggesting that successional species could become even more abundant in fragments over time. Nonetheless, the 52 species differed greatly in their responses to fragmentation and forest edges. Some disturbance-favoring pioneers (e.g., Cecropia sciadophylla, Vismia guianensis, V. amazonica, V. bemerguii, Miconia cf. crassinervia) increased by >1000% in density on edge plots, whereas over a third (19 of 52) of all species remained constant or declined in numbers. Species responses to fragmentation were effectively predicted by their median growth rate in nearby intact forest, suggesting that faster-growing species have a strong advantage in forest fragments. An ordination analysis revealed three main gradients in successional-species composition across our study area. Species gradients were most strongly influenced by the standlevel rate of tree mortality on each plot and by the number of nearby forest edges. Species-composition also varied significantly among different cattle ranches, which differed in their surrounding matrices and disturbance histories. These same variables were also the best predictors of total successional-tree abundance and species richness. Successional-tree assemblages in fragment interior plots (>150 m from edge), which are subjected to fragment area effects but not edge effects, did not differ significantly from those in intact forest, indicating that area effects per se had little influence on successional trees. Soils and topography also had little discernable effect on these species. Collectively, our results indicate that successional-tree species proliferate rapidly in fragmented Amazonian forests, largely as a result of chronically elevated tree mortality near forest edges and possibly an increased seed rain from successional plants growing in nearby degraded habitats. The proliferation of fast-growing successional trees and correlated decline of old-growth trees will have important effects on species composition, forest dynamics, carbon storage, and nutrient cycling in fragmented forests. 相似文献
635.
636.
A new framework for environmental assessment is needed because no existing framework explicitly includes all types of environmental
assessments. We propose a framework that focuses on resolving environmental problems by integrating different types of assessments.
Four general types of assessments are included: (1) condition assessments to detect chemical, physical, and biological impairments;
(2) causal pathway assessments to determine causes and identify their sources; (3) predictive assessments to estimate environmental,
economic, and societal risks, and benefits associated with different possible management actions; and (4) outcome assessments
to evaluate the results of the decisions of an integrative assessment. The four types of assessments can be neatly arrayed
in a two-by-two matrix based on the direction of analysis of causal relationships (rows) and whether the assessment identifies
problems or solves them (columns). We suggest that all assessments have a common structure of planning, analysis, and synthesis,
thus simplifying terminology and facilitating communication between types of assessments and environmental programs. The linkage
between assessments is based on intermediate decisions that initiate another assessment or a final decision signaling the
resolution of the problem. The framework is applied to three cases: management of a biologically impaired river, remediation
of a contaminated site, and reregistration of a pesticide. We believe that this framework clarifies the relationships among
the various types of assessment processes and their links to specific decisions. 相似文献
637.
Susan G. Jarvis Edwin C. Rowe Peter A. Henrys Simon M. Smart Laurence Jones Angus Garbutt 《Journal of Coastal Conservation》2016,20(2):107-116
Coastal environments host plant taxa adapted to a wide range of salinity conditions. Salinity, along with other abiotic variables, constrains the distribution of coastal plants in predictable ways, with relatively few taxa adapted to the most saline conditions. However, few attempts have been made to quantify these relationships to create niche models for coastal plants. Quantification of the effects of salinity, and other abiotic variables, on coastal plants is essential to predict the responses of coastal ecosystems to external drivers such as sea level rise. We constructed niche models for 132 coastal plant taxa in Great Britain based on eight abiotic variables. Paired measurements of vegetation composition and abiotic variables are rare in coastal habitats so four of the variables were defined using community mean values for Ellenberg indicators, i.e. scores assigned according to the typical alkalinity, fertility, moisture availability and salinity of sites where a species occurs. The remaining variables were the canopy height, annual precipitation, and maximum and minimum temperatures. Salinity and moisture indicator scores were significant terms in over 80 % of models, suggesting the distributions of most coastal species are at least partly determined by these variables. When the models were used to predict species occurrence against an independent dataset 64 % of models gave moderate to good predictions of species occurrence. This indicates that most models had successfully captured the key determinants of the niche. The models could potentially be applied to predict changes to habitats and species-dependent ecosystem services in response to rising sea levels. 相似文献
638.
McLoughlin E Rhodes AH Owen SM Semple KT 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):86-94
The effects of monoterpenes on the degradation of 14C-2,4-dichlorophenol (DCP) were investigated in soils collected from areas surrounding monoterpene and non-monoterpene-emitting vegetation. Indigenous microorganisms degraded 14C-2,4-DCP to 14CO2, after 1 d contact time. Degradation was enhanced by prior exposure of the soils to 2,4-DCP for 32 d, increasing extents of mineralisation up to 60%. Monoterpene amendments further enhanced 2,4-DCP degradation, but only following pre-exposure to both 2,4-DCP and monoterpene, with total 2,4-DCP mineralisation extents of up to 71%. Degradation was greatest at the higher monoterpene concentrations (≥1 μg kg−1). Total mineralisation extents were similar between concentrations, but higher than the control and the 0.1 μg kg−1 amendment, indicating that increases in monoterpene concentration has a diminishing enhancing effect. We suggest that monoterpenes can stimulate the biodegradation of 2,4-DCP by indigenous soil microorganisms and that monoterpene amendment in soils is an effective strategy for removing organic contaminants. 相似文献
639.
The anuric preterm newborn infant with a normal renal ultrasound: a diagnostic and ethical challenge
Dan Waisman Irena Kessel Nathan Ish-Shalom Lisa Maroun Shlomit Riskin-Mashiah Tzipora Falik-Zaccai Zalman Weintraub Susan Albersheim Avi Rotschild 《黑龙江环境通报》2006,26(4):350-353
Diagnosis and treatment of an anuric premature infant with severe respiratory compromise and a normal renal ultrasound (US), is a difficult task that requires a multidisciplinary approach. A 29-week gestation premature male infant, born after 5 weeks of worsening oligohydramnios, was ventilated for respiratory distress and remained anuric. Intensive clinical investigations and pediatric nephrology consultation that predicted very poor prognosis were followed by progressive renal failure, electrolyte imbalance, respiratory failure, ventricular arrhythmia, and finally cardiac arrest and death on day 5. In view of the predicted poor outcome, and after discussion with the parents, a decision was made not to start peritoneal dialysis (PD), and to offer only palliative therapy, with comfort care alone. Pre and postnatal diagnosis lead, in this case, to an ethical challenge that focuses on the question of futility. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
640.