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This study reports an investigation of the bryophyte ecology of minimally impacted high-latitude headwater streams, to assess the hypothesis that underlying geology, water physico-chemistry, current velocity and substrate morphology are significant environmental drivers of the species distribution, community composition and abundance of bryophyte vegetation in these naturally highly stressed and disturbed upland ecosystems. Our secondary aim was to determine whether there is evidence that the assemblage and functional attributes of the species present have potential as indicators of water quality and habitat biointegrity in high-latitude headwater streams. The methodology involved repeated intensive surveys, during 2005-2006, at nine sites located on three streams of contrasting underlying geology, within latitudes 56°-58°N, in upland Scotland. Using a stratified random sampling design, quantitative assessments were made of 5 stream vegetation parameters and 52 environmental variables potentially influencing the target sites. TWINSPAN classification, supported by CCA ordination, of the dataset identified four stream bryophyte community types, plus a fifth sample group (characterized by unstable habitat conditions) devoid of bryophytes. The environmental drivers of the vegetation community were primarily associated with streambed stability (flow, substrate composition) and water chemistry (e.g. pH, conductivity, Ca 2? ), which were products of the prevailing underlying geology. The abundance of stream bryophytes was generally a function of predominant growth morphology and life strategy of the species present. Two bryophyte assemblages were identified as characterizing either upland oligotrophic stream habitats of acid-sensitive and base-poor waters (indicators: Scapania undulata, Hygrohypnum ochraceum), or calcareous and mineral-rich streamwaters (indicators: Chiloscyphus polyanthus, Hygrohypnum luridum). The results support the incorporation of bryophytes into river biomonitoring schemes, for use in high-latitude upland streams.

Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner. The release of phosphorus (P) from bed sediments to the overlying water can delay , 2012;Spears et al., 2012;Sharpley et al., 2014). (over 3 days, as slurry from a pontoon) to control internal P loading, in an effort to Loch Flemington (Table 1) and likewise, being shallow, does not thermally stratify. 189This site also has sufficient data available and satisfies the BACI requirements for 190 the differences between sites to be relatively constant in the before period and not 191 subject to localised long-term random influences (e.g. large storms) during the study. 192The phytoplankton community in Loch Leven is, primarily, P limited and the loch has and cyanobacterial bloom intensity (using cyanobacteria biovolume) (see also , 1986). The null hypothesis is that there is no change in the difference in 262 the two time periods i.e. no effect of the La-bentonite application and where a 263 significant difference in the differences in the two time periods is detected at the 5% evidence that a large-scale driver i.e. weather, was influencing changes at both sites. 422Hence the increase in annual mean TP concentration may have been due to 423 enhanced internal P loading, associated with the drier and warmer than average 424 summer of 2013, when compared across the five year monitoring period (Table 4) essential and could potentially be discerned using long-term monitoring data. 441The phytoplankton compositional metric (PTI EQR) showed a sustained Implications of the results for future eutrophication management in lakes 468We have demonstrated the use of a BACI approach for detecting responses in shallow lake ecosystems (Hosper & Jagtman, 1990;Søndergaard et al., 2000; 532 Wichelen et al., 2007;Mehner et al., 2002 Mehner et al., & 2008 Duras & Dziaman, 2010). 533Controlling catchment-derived nutrient loading is a prerequisite for lasting lake 534 restoration efforts, otherwise internal stocks of nutrients will be replenished and 535 recovery periods protracted through their sediment release (Cooke et al., 2005). 536We have presented the first comprehensive assessment, using a BACI 546• This initial cyanobacterial response was not sustained beyond post-application 547 year two, implying a short lived reduction in internal P loading as a result of capping 548 sediment release. 549• The resumption in annual mean TP concentration, suggests that the La-bentonite 550 application was insufficient to control internal P loading for longer than two years. 551• Continual improvements in the phytoplankton compositional and abundance 552 metrics, not observed at the control site, may reflect a response to the sustained 553 reduction in annual mean FRP concentration following La-bentonite application. 554• The cyanobacterial bloom intensity metric is sensitive to inter-a...

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A new species Senecio repangae is described from the north-eastern North Island, New Zealand, where it grows primarily on offshore islands. It has previously been included within the widespread New Zealand endemic Senecio lautus, from which it is distinguished by its much taller, sparingly branched habit, longer and narrower capitula, much shorter, widely and unevenly spaced, recurved, incised ray florets, and by its chromosome number (2n = 100). A new subspecies, S. repangae subsp. pokohinuensis, endemic to the remote Mokohinau Islands group is also recognised. This allopatric taxon is distinguished from S. repangae subsp. repangae by its sparsely hairy, glabrescent, glaucous, adaxial leaf surface, smaller involucral bracts, and evenly spaced, longer, ray florets which are never recurved. The distribution, ecology, cytology, reproductive biology, conservation, and relationships of both subspecies to other New Zealand Senecio species are assessed.

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Diploneis fenestrata, a new aerophilic diatom is described from Lumangwe falls, Zambia. This novel species occurs as an epiphyte on the roots and stems of trees located within the spray zone of the falls. Its morphology was examined with both light and scanning electron microscopy. Diploneis fenestrata is distinguished from other taxa in the genus Diploneis by its prominent square openings ranging in number from 4-14 occurring within the area of the longitudinal canal only at the outer cell wall. The occurrence of these characteristic square openings found in the genus Diploneis is further discussed.