DNA barcoding was intended as a means to provide species-level identifications through associating DNA sequences from unknown specimens to those from curated reference specimens. Although barcodes were not designed for phylogenetics, they can be beneficial to the completion of the Tree of Life. The barcode database for Trichoptera is relatively comprehensive, with data from every family, approximately two-thirds of the genera, and one-third of the described species. Most Trichoptera, as with most of life's species, have never been subjected to any formal phylogenetic analysis. Here, we present a phylogeny with over 16 000 unique haplotypes as a working hypothesis that can be updated as our estimates improve. We suggest a strategy of implementing constrained tree searches, which allow larger datasets to dictate the backbone phylogeny, while the barcode data fill out the tips of the tree. We also discuss how this phylogeny could be used to focus taxonomic attention on ambiguous species boundaries and hidden biodiversity. We suggest that systematists continue to differentiate between ‘Barcode Index Numbers’ (BINs) and ‘species’ that have been formally described. Each has utility, but they are not synonyms. We highlight examples of integrative taxonomy, using both barcodes and morphology for species description.This article is part of the themed issue ‘From DNA barcodes to biomes’.
Codecision has been central to the efforts and energy of the European Parliament throughout the 1990s. But to what effect? This article considers the extent and nature of the influence that the Parliament had on legislation covered by the codecision provisions of the Maastricht Treaty (Art. 189B). It suggests that this influence can be explained in general terms, by the growth of shared norms between Council and Parliament, and in particular, by the specific characteristics of the distributive and regulatory policies covered by codecision. It concludes that the new Amsterdam provision (Art. 251) will reinforce the procedure as part of the acquis communautaire, but also open a broader debate about the role of the Parliament within the EU.
Codecision has dramatically increased the level of interaction and interdependence between the European Parliament and the Council of Ministers. Under Maastricht the two institutions were able to agree on a set of shared norms and rules to manage the interdependence arising from the conciliation procedure. The expansion and simplification of codecision under Amsterdam since May 1999 has started to generate significant strains on the further development of those norms and rules. In particular, it has provoked tension between the competing claims of efficiency and democracy in the framing of legislation. The way in which this is resolved will contribute substantially to the future institutional architecture of the EU.
Abstract. Spatial variations in soil processes regulating mineral N losses to streams were studied in a small watershed near Toronto, Ontario. Annual net N mineralization in the 0-8cm soil was measured in adjacent upland and riparian forest stands using in situ soil incubations from April 1985 to 1987. Mean annual rates of soil N mineralization and nitrification were higher in a maple soil (93.8 and 87.0 kg.ha-' ) than in a pine soil (23.3 and 8.2 kgha-I). Very low mean rates of mineralization (3.3 kg.ha-' ) and nitrification (3.4 kg.ha-r) were found in a riparian hemlock stand. Average NO,-N concentrations in soil solutions were 0.3-l.Omg.L-' in the maple stand and < 0.06mg.L-' in the pine stand. Concentrations of NO,-N in shallow ground water and stream water were 3-4 x greater in a maple subwatershed than in a pine subwatershed. Rapid N uptake by vegetation was an important mechanism reducing solution losses of NO,-N in the maple stand. Low rates of nitrification were mainly responsible for negligible NO,-N solution losses in the pine stand.htMdUCtiOll Undisturbed forested drainage basins often exhibit small annual stream losses of nitrogen in comparison to the large amounts of nitrogen circulated annually within the forest community. In contrast, disturbing the vegetation cover can cause elevated stream nitrate exports from some forest ecosystems (Vitousek et al. 1982). A number of soil processes regulate the amount of inorganic N that enters streams, including mineralization of organic N, vegetation uptake, immobilization of N by the microbial community, volatilization of ammonia, and denitrification. Nitrogen is transferred to streams by flowing water. Consequently, the amounts and specific routes of water movement within watersheds also affect stream N concentrations.Little research has been directed towards an understanding of how factors regulating N losses may vary spatially within small watershed ecosystems. Forest watersheds frequently contain upland and riparian vegetation communities that differ in composition, age and soil properties. Comparative regional studies across a range of forest and soil types have revealed con-
Macroinvertebrates are widely used for monitoring freshwater ecosystems. In most monitoring programs, identifications take substantial time and expense. Methods that improve the speed, accuracy and cost-effectiveness of macroinvertebrate identification would benefit such programs. Increasingly, DNA barcodes are being used to provide accurate species-level identifications and have the potential to change how macroinvertebrates are routinely identified. Herein we discuss the need for DNA barcodes of freshwater macroinvertebrates with particular reference to Australia. We examine the use of DNA barcodes for species identification and compare DNA barcoding efforts of macroinvertebrates from Australia with those globally. We consider the role of high-throughput sequencing of DNA barcodes in freshwater bioassessment and its potential use in biosurveillance. Finally, we outline a strategy for developing a comprehensive national DNA barcode database for Australian freshwater macroinvertebrates and present the initial efforts in creating this database.
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