@article{LauterbachRoemermannJeltschetal.2013,
  author    = {Lauterbach, D. and Roemermann, C. and Jeltsch, Florian and Ristow, Michael},
  title     = {Factors driving plant rarity in dry grasslands on different spatial scales: a functional trait approach},
  series = {BIODIVERSITY AND CONSERVATION},
  volume    = {22},
  journal   = {BIODIVERSITY AND CONSERVATION},
  number    = {10},
  publisher = {SPRINGER},
  address   = {DORDRECHT},
  issn      = {0960-3115},
  doi       = {10.1007/s10531-013-0455-y},
  pages     = {2337 -- 2352},
  year      = {2013},
  abstract  = {In European dry grasslands land-use changes affect plant species performance and frequency. Potential driving forces are eutrophication and habitat fragmentation. The importance of these factors is presumably scale dependent. We used a functional trait approach to detect processes that influence species frequency and endangerment on different spatial scales. We tested for associations between functional traits and (1) frequency and (2) degree of endangerment on local, regional and national scales. We focussed on five selected traits that describe the life-history of plant species and that are related to competition, dispersal ability and habitat specificity. Trait data on plant height, SLA, plant coverage, peak of flowering and diaspore mass were measured for 28 perennials from common to rare and endangered to non-endangered on 59 dry grassland sites in north-eastern Germany. Multiple regression models revealed that species frequency is positively and species endangerment negatively related to plant height, plant coverage and SLA on more than one spatial scale. On the local scale, diaspore mass has a negative effect on species frequency. More frequent and less endangered species show a later peak of flowering on nationwide and regional scales. We concluded that competition traits are more important on larger scales, whereas dispersal traits are more important for species frequency on the smaller scale. On national and regional scales, eutrophication and habitat loss may be the main drivers of species threat, whereas on the local scale fragmentation plays a crucial role for the performance of dry grassland species.},
  language  = {en}
}
@article{HundBrownLavkulichetal.2013,
  author    = {Hund, Silja V. and Brown, Sandra and Lavkulich, Les M. and Oswald, Sascha Eric},
  title     = {Relating P Lability in Stream Sediments to Watershed Land Use via an Effective Sequential Extraction Scheme},
  series = {Water, air \& soil pollution : an international journal of environmental pollution},
  volume    = {224},
  journal   = {Water, air \& soil pollution : an international journal of environmental pollution},
  number    = {9},
  publisher = {Springer},
  address   = {Dordrecht},
  issn      = {0049-6979},
  doi       = {10.1007/s11270-013-1643-9},
  pages     = {13},
  year      = {2013},
  abstract  = {High applications of P fertilizers and manure are general practice in intensive agriculture and may cause eutrophication in adjacent streams. Bioavailability of P can be estimated by sequential extractions commonly used for soil or sediment. A single combined method may facilitate more effective comparisons of topsoils and adjoining stream sediments, and enhance management decisions. In this study, the suitability of an established soil P sequential extraction was tested on stream bed sediments. The study was conducted in the Sumas River watershed in the agricultural Lower Fraser Valley, Canada. Sediment samples with differing land use (forest, low and high intensity agriculture) from 1993, 1994, 2008, and 2009 from 14 sites along the Sumas River and tributaries were used. Total sequential extraction concentrations were in agreement with aqua regia digestion (Rs=0.96) and showed consistency over the study time sequence. P fractions released by 0.5 M NaHCO3 (median 14 \%), 0.1 M NaOH (33 \%), and 1.0 M HCl (38 \%) were significantly (alpha=0.05) higher than P released by other extractants. These three extraction steps provide a practical and time-effective assessment of P lability in stream sediments and may be used as a combined scheme for sediment and soil. Analytical results further revealed that land use has a major and characteristic impact on P lability. With a land use change from forest to intensive agriculture, results showed an increase in total P concentrations (30 to 4,000 ppm) and in P lability, in particular for the moderately labile NaOH-P fraction (20 to 50 \%).},
  language  = {en}
}