The oxygen isotope evolution of parent body aqueous solutions as recorded by multiple carbonate generations in the Lonewolf Nunataks 94101 CM2 carbonaceous chondrite

The CM2 carbonaceous chondrite LON 94101 contains aragonite and two generations of calcite that provide snapshots of the chemical and isotopic evolution of aqueous solutions during parent body alteration. Aragonite was the first carbonate to crystallize. It is rare, heterogeneously distributed within the meteorite matrix, and its mean oxygen isotope values are δ18O 39.9±0.6‰, Δ17O -0.3±1.0‰ (1σ). Calcite precipitated very soon afterwards, and following a fall in solution Mg/Ca ratios, to produce small equant grains with a mean oxygen isotope value of δ18O 37.5±0.7‰, Δ17O 1.4±1.1‰ (1σ). These grains were partially or completely replaced by serpentine and tochilinite prior to precipitation of the second generation of calcite, which occluded an open fracture to form a millimeter-sized vein, and replaced anhydrous silicates within chondrules and the matrix. The vein calcite has a mean composition of δ18O 18.4±0.3‰, Δ17O -0.5±0.5‰ (1σ). Petrographic and isotopic results therefore reveal two discrete episodes of mineralization that produced Ca-carbonates with contrasting δ18O, but whose Δ17O values are indistinguishable within error. The aragonite and equant calcite crystallized over a relatively brief period early in the aqueous alteration history of the parent body, and from static fluids that were evolving chemically in response to mineral dissolution and precipitation. The second calcite generation crystallized from solutions of a lower Δ17O, and a lower δ18O and/or higher temperature, which entered LON 9410 via a fracture network. As two generations of calcite whose petrographic characteristics and oxygen isotopic compositions are similar to those in LON 94101 occur in at least one other CM2, multiphase carbonate mineralization could be the typical outcome of the sequence of chemical reactions during parent body aqueous alteration. It is equally possible however that the second generation of calcite in formed in response to an event such as impact fracturing and concomitant fluid mobilisation that affected a large region of the common parent body of several CM2 meteorites. These findings show that integrated petrographic, chemical and isotopic studies can provide new insights into the mechanisms of parent body alteration including the spatial and temporal dynamics of the aqueous system

Environmental Indicators for the Coastal Region of the U.S. Great Lakes

The goal of this research collaboration was to develop indicators that both estimate environmental condition and suggest plausible causes of ecosystem degradation in the coastal region of the U.S. Great Lakes. The collaboration consisted of 8 broad components, each of which generated different types of environmental responses and characteristics of the coastal region. These indicators included biotic communities of amphibians, birds, diatoms, fish, macroinvertebrates, and wetland plants as well as indicators of polycyclic aromatic hydrocarbon (PAH) photo-induced toxicity and landscape characterization. These components are summarized below and discussed in more detailed in 5 separate reports (Section II). Stress gradients within the U.S. Great Lakes coastal region were defined from 207 variables (e.g., agriculture, atmospheric deposition, land use/land cover, human populations, point source pollution, and shoreline modification) from 19 different data sources that were publicly available for the coastal region. Biotic communities along these gradients were sampled with a stratified, random design among representative ecosystems within the coastal zone. To achieve the sampling across this massive area, the coastal region was subdivided into 2 major ecological provinces and further subdivided into 762 segment sheds. Stress gradients were defined for the major categories of human-induced disturbance in the coastal region and an overall stress index was calculated which represented a combination of all the stress gradients. Investigators of this collaboration have had extensive interactions with the Great Lakes community. For instance, the Lake Erie Lakewide Area Management Plan (LAMP) has adopted many of the stressor measures as integral indicators of the condition of watersheds tributary to Lake Erie. Furthermore, the conceptual approach and applications for development of a generalized stressor gradient have been incorporated into a document defining the tiered aquatic life criteria for defining biological integrity of the nation’s waters. A total of 14 indicators of the U.S. Great Lakes coastal region are presented for potential application. Each indicator is summarized with respect to its use, methodology, spatial context, and diagnosis capability. In general, the results indicate that stress related to agricultural activity and human population density/development had the largest impacts on the biotic community indicators. In contrast, the photoinduced PAH indicator was primarily related to industrial activity in the U.S. Great Lakes, and over half of the sites sampled were potentially at risk of PAH toxicity to larval fish. One of the indicators developed for land use/land change was developed from Landsat imagery for the entire U.S. Great Lakes basin and for the period from 1992 to 2001. This indicator quantified the extensive conversions of both agricultural and forest land to residential area that has occurred during a short 9 year period. Considerable variation in the responses were manifest at different spatial scales and many at surprisingly large scales. Significant advances were made with respect to development of methods for identifying and testing environmental indicators. In addition, many indicators and concepts developed from this project are being incorporated into management plans and U.S. 8 EPA methods documents. Further details, downloadable documents, and updates on these indicators can be found at the GLEI website - http://glei.nrri.umn.edu

Natural Resources Research Institute Technical Report

• A total of 132, 133, and 164 stands (1,254 survey points) were surveyed for breeding birds in the Chequamegon, Chippewa, and Superior National Forests (NF), respectively in 2006. Annual surveys have been conducted since 1991 in the Chippewa and Superior NF, and since 1992 in the Chequamegon NF. • Comprehensive surveys of vegetation structure were carried out on 93, 74, and 63 points in the Chequamegon, Chippewa, and Superior NFs, respectively, on over 50 observer-days of sampling. Monitoring personnel on the Chippewa and Superior NFs provided excellent assistance in the coordination and completion of this effort. • Trends in relative abundance were calculated for 72 bird species, including 57 species in the Chequamegon NF, 57 in the Chippewa NF, and 49 in the Superior NF. Thirty-nine species were also tested for a pooled trend by combining data from the three national forests. • A total of 163 species/national forest trends were calculated in 2006 (not including pooled trends), 68 (42%) of which were significant (P ≤ 0.05). Twenty three species increased significantly (P ≤ 0.05) in at least one national forest and 24 species decreased. Eleven species had significant increasing pooled trends and 11 had decreasing trends. Of the 158 species/national forest trends calculated in 2005, 19 (12%) changed in 2006. • The percent of increasing species on each national forest ranged from 9% in the Chequamegon NF, to 25% in the Chippewa NF. The percent of decreasing species ranged from 20% in the Superior NF, to 28% in the Chequamegon NF. • The short-distance migrant guild showed highly significant declines on all national forests. Long-distance migrants also declined on all national forests. Permanent residents increased on the Chippewa and Superior NF and in the pooled NFs, but were stable on the Chequamegon NF. • The ground nesting guild showed highly significant declines on all national forests. Shrub/sub-canopy nesters increased on Chippewa NF, but were stable in Chequamegon and Superior NFs. Canopy nesters increased in Chquamegon NF and cavity-nesters increased in Chippwa and Superior NFs. All nesting guilds showed significant trends in the pooled NFs with increases in shrub/subcanopy-nesters and cavity-nesters and decreases in ground- and canopy-nesters. • The deciduous and mixed forest bird guilds declined on the Chequamegon and Superior NFs and the pooled NFs. The lowland coniferous forest bird guild declined on the Chippewa NF and the pooled NFs. The early-successional bird guild increased on the Chippewa NF and the upland coniferous bird guild increased on the Chippewa and Superior NFs as well as in the pooled NFs. • Evidence from previous regional studies have demonstrated greater nest predation rates on ground nests near forest/clearcut edges, as well as a significant increase in the creation of forest edges in recent years. Increasing amounts of forest edge and nest predation may be having negative effects on declining ground-nesters such as the Winter Wren, Veery, Hermit Thrush, Ovenbird, and White-throated Sparrow. • Of the 1274 survey sites on the three national forests, 15.5% have been at least partially harvested since the beginning of monitoring, which is about 1% a year. This harvest rate is comparable to the documented 4.8% change from mature forest to early-successional types on federally managed forest lands in northeastern Minnesota between 1990 and 1995 (i.e., ~1% annual change). Thus, it appears that management activities on our sample sites are representative of the national forests as a whole, and that the trends we are documenting are probably occurring across the regional landscape. • Many of the declining trends that we have detected appear to be consistent across years instead of being due to a few years with very low or high abundance. One of the main goals of this monitoring program is to identify potential declines of forest bird species, especially for species of conservation concern such as the Eastern Wood-Pewee, Winter Wren, Hermit Thrush, Ovenbird, and White-throated Sparrow. The declines observed over the past years for common species such as the Ovenbird and White-throated Sparrow are a continuing concern and special management consideration should be given to these species

Hourly variation in transect counts of birds

We examined hourly variation in numbers of birds detected during morning line transect counts in northern Wisconsin and Upper Peninsula Michigan . We analyzed hourly variation by month (May-September), year (1986, 1987 ; 1985-June only), and state . Mean number of individuals detected generally was highest during the first or second hour in each state. Hourly differences in total individuals were significant in 1 of 1 1 monthly samples in Wisconsin and in 4 of 11 in Michigan . Lowest counts of total individuals were recorded during the fourth hour. No significant difference among hours was detected in mean number of species detected per hour in Wisconsin. Differences were significant in three Michigan samples and approached significance (P < 0.06) in a fourth . Lowest counts of total species occurred during the fourth hour. Individual species varied in hourly trends ; some increased during the morning, some decreased, and others showed no consistent pattern in number of individuals detected per hour. Hourly differences in abundance of individual species were significant in 12 of 61 comparisons (20%) in Wisconsin but in only 1 of 62 (2%) in Michigan

Natural Resources Research Institute Technical Report

A total of 135, 168, and 133 stands (1,268 survey points) were surveyed for breeding birds in the Chippewa, Superior, and Chequamegon National Forests, respectively. Surveys have been completed for nine years in the Chippewa and Superior, and for eight years in the Chequamegon NF. Breeding bird surveys in the St. Croix region of Minnesota have been conducted over the last eight years at 171 points. Surveys in Southeast Minnesota have been conducted over the last five years at 211 points. We were able to examine trends in abundance for 79 bird species in at least one of the five study areas. Fifty-two species in the Chequamegon NF, 48 species in the Superior NF, 53 species in the Chippewa NF, 33 species in the St. Croix region, and 35 species in Southeast Minnesota were tested. Sixteen species showed a significant increase in at least one of the five study areas, and 13 species showed a significant decrease. Of the 16 increasing species, the American Robin, Yellow-rumped Warbler, and American Redstart showed significant increases in more than one study area. Of the 13 decreasing species, six declined significantly in more than one study area. The Eastern Wood-Pewee, Black-and-white Warbler, Ovenbird, Mourning Warbler, and Brown-headed Cowbird declined in two study areas and the White-throated Sparrow declined in three study areas

Lebensbedingungen der DDR-Jugend Parlamentsstudie 1975 ; Teilbericht III.1.-3

UuStB Koeln(38)-940106659 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman