The adaptation of two similar soils to pyrene catabolism

The development of pyrene catabolic activity was assessed in two similar soils (pasture and woodland) amended with 100 mg pyrene kg(-1) In the pasture and woodland soils, significant mineralisation of 14C-pyrene was observed after 8 and 76 weeks soil-pyrene contact times, respectively. In both soils, there were significant decreases (P<0.05) in the lag times and significant increases (P <0.05) in the maximum rates and extents of 14C-pyrene mineralised with increasing soil-pyrene contact time. A microbial inoculum was added to the woodland soil to assess if the previously added, but undegraded 14C-pyrene was bioavailable at 16 and 24 weeks. This resulted in the immediate mineralisation of the previously added 14C-pyrene, indicating that it was bioavailable but that the microbial community in the woodland soil had not developed the ability to mineralise pyrene. The relative contributions of the indigenous microflora to 14C-pyrene mineralisation were assessed by the addition of celective inhibitors, with bacteria seeming to be responsible for the mineralisation of pyrene in both soils. It is suggested that the rate of pyrene-transfer from the soil to the microorganisms was lower in the woodland soil due to its higher organic matter content.     

Monitoring polycyclic aromatic hydrocarbons (PAHs) and heavy metals in urban soil,compost and vegetation

Samples of urban surface soil, composts, leaves from avenue limetrees and grass from park areas of the city of Basel (Switzerland) were analysed for polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Generally, significant lower levels of PAHs (10 times lower) and heavy metals (3–70 times lower) were found in vegetation samples than in composts or soils. The concentrations of PAHs in soil and compost samples were in the same order of magnitude although 10–100-times higher in comparison to data given for rural soils in other studies, whereas heavy metal contents in urban soils and composts were 2–3 times higher than in rural samples. Using multivariate statistical analysis, it was possible to define similarities or special characteristics of single substances or substance groups in a given matrix reflecting their chemical properties and providing information on their specific emission sources.     

Male characteristics,parental quality and the study of mate choice in the red-winged blackbird (Agelaius phoeniceus)

Summary A demonstration of adaptive mate choice by females in resource-defence mating systems requires clear predictions as to how females should rank breeding situations (defined by the quality of both the resident male and the territory he defends) so as to maximize their fitness. Since male quality is only weakly correlated with territory quality in red-winged blackbirds (Agelaius phoeniceus), ranking breeding situations in this species will require a consideration of both those parameters independently of each other as long as both vary among males, are predictable before mating, and affect female fitness. Data from a two year study of an eastern Ontario population of this species suggested that two components of male parental quality, nest defence effort and provisioning of nestlings with food, both varied among males and were somewhat predictable. Two measures of nest defence effort were correlated with an index of epaulet size (a reliable predictor of captive dominance rank in this species) (Table 5), and provisioning appeared to be predictable on the basis of both courtship behavior and breeding experience. Our data also suggest that these two components of male parental quality do not covary. Since male provisioning tends to be restricted to the nestlings of the primary and secondary mates in this species, breeding situations must be ranked not only with respect to their manifold quality but also with respect to the mating status of individual females.     

Unintended biological invasions: Does risk vary by trading partner?

International trade is the primary conduit for unintentional and damaging species introductions. But biogeographic heterogeneity, and differences in historical trade exposure across trade partners suggest that not all imports are equally risky. We develop an analytical model linking exotic species introductions and discoveries to trade volumes. The model is estimated using a novel historical data set on global trade and species introductions by region. Our estimates support theoretical predictions that trade from different regions poses different risks and that the cumulative number of introductions from a region is a concave function of imports. For each trade region we then calculate the marginal and cumulative invasion risk from additional trade. Simple volume restrictions on imports to reduce NIS introductions are not advisable based on coarse cost–benefit calculations.     

Synergistic effects of lead,salinity and temperature on embryonic development of the mussel Mytilus galloprovincialis

Combined effects of lead, salinity and temperature on the embryonic development of the mussel Mytilus galloprovincialis Lmk. were studied under laboratory conditions. The basic experimental design was a 4x6 factorial experiment using 4 lead concentrations (100, 250, 500 and 1000 ppb Pb²⁺) and 6 salinity levels (from 25 to 37.5 with 2.5 intervals). These factorial designs were carried out at three constant temperatures (150, 17.50 and 20°C). The statistical analysis indicated that salinity changes have more effect on the embryonic development than temperature. Optimal development was observed at 34.8 and 15.6°C, which is in accordance with observations in the field. The effect of lead was mininal in optimal salinity and temperature conditions. The deleterious effect of lead on the embryonic development was especially conspicuous at 20°C. Since in nature spawning occurs at temperatures inferior to 20°C, lead will probably not drastically decrease the potential recruitment of mussel spat in the littoral populations of the northern Adriatic Sea, where the salinity of the water is relatively stable. Under experimental conditions, lead caused a delay or inhibition of the embryonic development with the occurrence of a large number of abnormal larvae.     

Managing troubled data: coastal data partnerships smooth data integration

Understanding the ecology, condition, and changes of coastal areas requires data from many sources. Broad-scale and long-term ecological questions, such as global climate change, biodiversity, and cumulative impacts of human activities, must be addressed with databases that integrate data from several different research and monitoring programs. Various barriers, including widely differing data formats, codes, directories, systems, and metadata used by individual programs, make such integration troublesome. Coastal data partnerships, by helping overcome technical, social, and organizational barriers, can lead to a better understanding of environmental issues, and may enable better management decisions. Characteristics of successful data partnerships include a common need for shared data, strong collaborative leadership, committed partners willing to invest in the partnership, and clear agreements on data standards and data policy. Emerging data and metadata standards that become widely accepted are crucial. New information technology is making it easier to exchange and integrate data. Data partnerships allow us to create broader databases than would be possible for any one organization to create by itself.     

A longitudinal assessment of the aquatic macroinvertebrate community in the channelized lower Missouri River

We conducted an aquatic macroinvertebrate assessment in the channelized reach of the lower Missouri River, and used statistical analysis of individual metrics and multimetric scores to identify community response patterns and evaluate relative biological condition. We examined longitudinal site differences that are potentially associated with water qualityrelated factors originating from the Kansas City metropolitan area, using data from coarse rock substrate in flowing water habitats (outside river bends), and depositional mud substratein slack water habitats (dike fields). Three sites above rivermile (RM) 369 in Kansas City (Nebraska City, RM = 560; St. Joseph, RM = 530; Parkville, RM = 377) and three below (Lexington, RM = 319; Glasgow, RM = 228; Hermann, RM = 94) were sampled with rock basket artificial substrates, a qualitative kicknet method, and the Petite Ponar. We also compared the performance of the methods used. A total of 132 aquatic macroinvertebrate taxa were collected from the lower Missouri River; one third of these taxa belonged to the sensitiveEPOT insect orders (Ephemeroptera, Plecoptera, Odonata, and Trichoptera). Rock baskets had the highest mean efficiency (34.1%) of the methods, and the largest number of taxa was collected by Ponar (n = 69) and kicknet (n = 69) methods. Seven of the 15 metrics calculated from rock basket data, and five ofthe nine metrics calculated from Ponar data showed highly significant differences (ANOVA, P < 0.001) at one or more sitesbelow Kansas City. We observed a substantial reduction in net-spinning Trichoptera in rock habitats below Kansas City (Lexington), an increase in relative dominance of Oligochaeta in depositional habitats at the next site downstream (Glasgow), and lower relative condition scores in rock habitat at Lexingtonand depositional habitat at Glasgow. Collectively, these data indicate that some urban-related impacts on the aquatic macroinvertebrate community are occurring. Our results suggest that the methods and assessment framework we used in this studycould be successfully applied on a larger scale with concurrentwater and sediment chemistry to validate metrics, establish impairment levels, and develop a specific macroinvertebrate community index for the lower Missouri River. We recommend accomplishing this with longitudinal multi-habitat sampling at a larger number of sites related to all potential sources of impairment, including major tributaries, urban areas, and point sources.     

Concentrations of Arsenic, Cadmium, Copper, Lead, Selenium, and Zinc in Fish from the Mississippi River Basin, 1995

Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 12 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB), and in late 1996 from a reference site in West Virginia. The NCBP sites represented key points (dams, tributaries, etc.) in the largest rivers of the MRB. The NAWQA sites were typically on smaller rivers and were selected to represent dominant land uses in their watersheds. The West Virginia site, which is in an Eastern U.S. watershed adjacent to the MRB, was selected to document elemental concentrations in fish used for other aspects of a larger study and to provide additional contemporaneous data on background elemental concentrations. At each site four samples, each comprising (nominally) 10 adult common carp (Cyprinus carpio, 'carp') or black bass (Micropterus spp., 'bass') of the same sex, were collected. The whole fish were composited by station, species, and gender for analysis of arsenic (As), lead (Pb), and selenium (Se) by atomic absorption spectroscopy and for cadmium (Cd), copper (Cu), and zinc (Zn) by inductively-coupled plasma emission spectroscopy. Concentrations of most of the elements examined were lower in both carp and bass from the reference site, a small impoundment located in a rural area, than from the NCBP and NAWQA sites on rivers and larger impoundments. In contrast, there were few overall differences between NCBP sites NAWQA sites. The 1995 results generally confirmed the continued weathering and re-distribution of these elemental contaminants in the MRB; concentrations declined or were unchanged from 1984-1986 to 1995 at most NCBP sites, thus continuing two-decade trends. Exceptions were Se at Station 77 (Arkansas R. at John Martin Reservoir, CO), where concentrations have been elevated historically and increased slightly (to 3.8-4.7 microg g-(1) in bass and carp); and Pb, Cd, and Zn at Station 67 (Allegheny R. at Natrona, PA), where levels of these metals were high in the past and increased from 1986 to 1995.