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[en] The goal of this field review was to provide information to the Bonneville Power Administration (BPA) regarding previous and ongoing fish habitat improvement projects in central Idaho. On July 14, 1992, the review team met at the Sawtooth National Recreation Area office near Ketchum, Idaho, for a slide presentation illustrating several habitat projects during their construction phases. Following the slide presentation, the review team inspected fish habitat projects that have been implemented in the last several years in the Stanley Basin and adjacent valleys. At each site the habitat project was described to the field team and a brief period for project inspection followed. The review team visited approximately a dozen sites on the Challis, Sawtooth, and Boise National Forests over a period of approximately two and a half days. There are two objectives of this review namely to summarize observations for specific field sites and to provide overview commentary regarding the BPA habitat improvement program in central Idaho
[en] We studied the effect of burning frequency on the density and species richness of understory flowering stems in a Florida sandhill. Flowering stems were censused weekly for 54 weeks in six sites that had been burned one to six times in the previous 16 years. We concurrently measured overstory characteristics such as species composition, density and basal area. We used maximum likelihood and Akaike's Information Criterion to compare linear, quadratic, saturating, and null models of community response to repeating burning. We did not find a relationship between species richness, diversity or flowering stem density and fire frequency. Tree density was related to fire frequency and may represent an indirect pathway for fire effects on understory characteristics. While we found no support for the Intermediate Disturbance Hypothesis, an analysis of our experimental design indicated that we had low statistical power. We develop the hypothesis that a saturating model of response to fire best describes understory species richness in our system. We test this hypothesis using the most extensive published fire data set we are aware of and find support for a saturating model
[en] Indrasarobar reservoir at Kulekhani, Nepal, was formed by damming the Kulekhani River as part of long-term hydroelectric power development. Construction was completed in 1981 and the reservoir which formed is ca 7 km long, 380 m wide, and has a volume of 85.3 million m3. The valley in which the reservoir is located has steep sides, consequently the water level varies greatly, from a maximum depth of 105 m to as low as 78 m. Changes in the fish species composition resulting from the river damming are discussed. There has been a decline in bottom-feeding insectivores, especially of the families Cobitidae, Channidae, Sisoridae, and Cyprinidae. In particular, Garra lamta and Puntius species have disappeared and Schizothorax richardsoni has declined sharply. Native omnivorous species such as Accrossocheilus haxagonolepis and Puntius chilinoides have become dominant. The growth of planktivorous carps, Hypophthalmichthys molitrix and Aristichthys nobilis, is similar to growth in other areas of Nepal. The changes in the fish population in Indrasarobar and other artificial Indian lakes are briefly compared. 15 refs., 3 figs., 2 tabs
[en] When biomass is a substantial sustainable energy source, and special energy crops are grown on a large scale, land use and the environment of agriculture will be affected. Of these effects, biodiversity deserves special attention. The enhancement of biodiversity in energy farming via standard setting is the overall purpose of this project. In this study, the potential functionality of biodiversity in energy farming is proposed as a way of operationalising the rather abstract and broad concept of biodiversity. Functions of biodiversity are reviewed, and examples of functions are worked out, based on the current literature of nature in energy farming systems. (author)
[en] In the discussion on imports of biomass a number of obstacles are mentioned. It is very important to know these barriers and to find out how they may be overcome. Questions to be answered are (1) Which are the main objections against import of biomass (negative impacts on biodiversity, competition with the production of food, disbalance of nutrients, etc); (2) Is it possible to quantify these objections?; and (3) What are the possibilities to overcome these barriers? The Biomass Upstream Steering committee (BUS), consisting of the participating consortium partners, was created to generate new ideas, select and rank the most promising ones to be worked out in more detail and to invite market parties to jointly set up R and D projects on upstream biomass
[en] Ecological theory provides applications to biodiversity management but often falls short of expectations. One possibility is that heuristic theories of a young science are too immature. Logistic growth predicts a carrying capacity, but fisheries managed with the Lotka-Volterra paradigm continue to collapse. A second issue is that general predictions may not be useful. The theory of island biogeography predicts species richness but does not predict community composition. A third possibility is that the theory itself may not have much to do with nature, or that empirical parameterization is too difficult to know. The meta population paradigm is relevant to conservation, but meta populations might not be common in nature. For instance, empirical parameterization within the meta population paradigm is usually infeasible. A challenge is to determine why ecology fails to match needs of managers sometimes but helps at other. Managers may expect too much of paradigmatic blueprints, while ecologists believe them too much. Those who implement biodiversity conservation plans need simple, pragmatic guidelines based on science. Is this possible. What is possible An eclectic review of theory and practice demonstrate the power and weaknesses of the ideas that guide conservation and attempt to identify reasons for prevailing disappointment.
[en] The primary objective of this project is to investigate the effects of global change on the biodiversity of aphid communities in Western Europe. Biodiversity has been examined at 3 levels: total number of species, phenology and reproductive strategy. Data were provided by EXAMINE, the European suction traps network which has been now operating for 35 years. 392 different species have been identified. At each location, total number of species has been regularly increasing, one additional species being caught every 1 or 2 years depending on location. This is due to introduced species but also to warming which favours rare species. No general trend of increasing density has been detected, but phenological earliness of almost all species (annual date of first appearance in suction traps) is strongly correlated with temperature and especially with mean daily temperature (during more or less long periods of time lying principally in February and March) or number of days below 0 C. Strong relationships between aphid phenology and environmental variables have been found and there is strong discrimination between species with different life cycle strategies, and between species feeding on herbs and trees, suggesting the possible value of trait-based groupings in predicting responses to environmental changes. These preliminary results suggest that 1) biodiversity has increased during the last decades; 2) there is a pool of species among which some of them reach a detectable density only during years where temperatures are high enough; 3) a set of newly introduced species succeed in settling being favoured by warming and 4) phenology of aphids is expected to advance and their abundance to increase with temperature, and the possible role of natural enemies to regulate abundant species is discussed. (author)
[en] This paper is a preliminary attempt to provide information on the probable environmental effects of energy crop production relative to other potential uses of the land. While dedicated energy crop production is anticipated to occur primarily on land currently in agricultural production, some pastureland and forestland with a high potential for conversion to agricultural production may be utilized. Experimental results suggest that chemical use on energy crops will be lower than on most row crops and that land producing energy crops should experience less erosion than land producing row crops. Long-term site productivity should not be a major issue if macro-and micro-fertilizers are added as needed and nutrient-conserving production techniques are used. (Author)
[en] Highlights: • Biodiversity and ecosystem services of biomass crops were studied at plot to landscape levels. • Metrics of biodiversity included taxonomic richness of plants, insects, soil microbes and birds. • Biodiversity and ecosystem processes generally increased with increasing perenniality and within-crop diversity. • Evaluating tradeoffs among ecosystem services can inform biomass crop selection and placement in agricultural landscapes. - Abstract: Biomass cropping systems have the potential to alter the ecosystem services provided by agricultural landscapes. Depending on crop type and management, strategic incorporation of biomass cropping systems into existing agricultural landscapes could enhance a range of ecosystem services while mitigating some disservices. Here, we review the approaches and findings of eight years of research into the potential effects of a range of biomass cropping systems on ecosystem services in the North Central US. Our research was framed by an initial assessment of the abundance and distribution of multiple taxa (i.e., biodiversity) within candidate biomass cropping systems. The processes underpinning important ecosystem services in each system were then measured or modeled, related to biodiversity metrics, and used to explore the influence of management scenarios on biodiversity and ecosystem processes. We also used these data and models to develop a decision support system that allows stakeholders to consider tradeoffs and synergies under alternative landscape composition, configuration, and agronomic management. Perennial grass cropping systems provided the greatest potential to promote multiple ecosystem services. More diverse perennial grasslands that include forbs have the potential to increase pest suppression and pollination, decrease greenhouse gas emissions, and enhance grassland bird communities, but likely at the expense of biomass yield. Providing stakeholders and policymakers with information about the expected mix of ecosystem services supported by different biomass feedstock cropping systems in advance of their adoption offers the potential for informed choices to guide the implementation and management of future biomass-producing landscapes.
[en] This study focused on the ecology of abandoned peatlands in Finland. The aim is to produce information about conditions favourable for recolonisation and regeneration of mires. This could serve as a basis for the management of milled peat cut-over sites which are designed for rewetting