scholarly journals Nutrient loading by anadromous fishes: species-specific contributions and the effects of diversity

2017 ◽  
Vol 74 (4) ◽  
pp. 609-619 ◽  
Author(s):  
Cornelia W. Twining ◽  
Eric P. Palkovacs ◽  
Maya A. Friedman ◽  
Daniel J. Hasselman ◽  
David M. Post
Keyword(s):  
Life History ◽  
Native American ◽  
Functional Traits ◽  
Nutrient Loading ◽  
Columbia River ◽  
Freshwater Ecosystems ◽  
Nutrient Inputs ◽  
Connecticut River ◽  
Fresh Waters ◽  
Key Species

Anadromous fishes exhibit diverse life history and functional traits. Spawning anadromous fishes bring nutrients to fresh waters, and their life history and functional traits can influence nutrient loading patterns. We asked how nutrient inputs varied across 12 species of North American anadromous fishes and how these patterns affected river-wide trends in nutrient loading. We used portfolio effect analyses to assess whether diversity stabilized or destabilized nutrient inputs to freshwater ecosystems over time. Recent decreases in body size reduced per individual nutrient loading for several key species, which in turn decreased cumulative loading. Invasion also altered nutrient loading; non-native American shad (Alosa sapidissima) now provide nearly half of the annual marine-derived nutrient inputs to the Columbia River. Counter to expectations, species diversity (richness and evenness) did not significantly increase the stability of nutrient inputs to fresh waters. Species loss in the Connecticut River increased stability, while species gain in the Columbia River decreased stability.

scholarly journals The untapped potential of conservation journals to promote freshwater biodiversity

2020 ◽  
Author(s):  
Fengzhi He ◽  
Sonja C. Jähnig ◽  
Annett Wetzig ◽  
Simone D. Langhans
Keyword(s):  
Life History ◽  
Biodiversity Conservation ◽  
General Public ◽  
Marine Ecosystems ◽  
Freshwater Ecosystems ◽  
Freshwater Species ◽  
Freshwater Biodiversity ◽  
Extinct Species ◽  
Marine Turtles ◽  
Fresh Waters

AbstractFreshwater ecosystems are amongst the most diverse ecosystems on the planet. They are subject to intense and increasing threats and have a higher proportion of threatened and extinct species than terrestrial or marine realms. Concurrently, freshwater ecosystems are largely underrepresented in both conservation research and actions arguably as a consequence of less popularity and promotion. To test this assumption, we used cover images as a proxy of exposure and promotion opportunities provided by conservation journals. We collected information on cover images of 18 conservation journals from 1997 to 2016 and data on citations and Altmetric scores of papers published in them. We found that freshwater ecosystems (10.4%) were featured less often than marine (15.2%) or terrestrial (74.4%) ecosystems on covers of these journals. All 15 most featured species are from terrestrial or marine ecosystems, with 14 of them being large vertebrates such as elephants, big cats, rhinos, polar bears, and marine turtles. None of the 95 species featured more than once on the covers of conservation journals spend their whole life history in fresh waters, i.e. they are at least partly associated with terrestrial or marine ecosystems. Our results indicated that cover-featured studies received more attention from academia and the general public, i.e. showed higher citations and Altmetric scores, than non-featured ones within the same issue. By featuring freshwater species and habitats on covers, therewith providing more exposure opportunities, conservation journals hold the potential to promote biodiversity conservation in fresh waters. Scientists can help that endeavour by submitting freshwater-related photos together with their manuscripts for review, therewith providing more options for editors to portray freshwater species and habitats and to ultimately raise awareness and appreciation of freshwater life.

The Odd Man Out in a Pioneer Cemetery at Seccombe Lake Park, San Bernardino, California

2020 ◽  
pp. 90-113
Author(s):  
Patricia M. Lambert
Keyword(s):  
Life History ◽  
Native American ◽  
Morphological Traits ◽  
The Other ◽  
European Ancestry ◽  
Latter Day Saints ◽  
Community Members ◽  
San Bernardino ◽  
History Of ◽  
The 19Th Century

In 1989, a pioneer cemetery associated with the 19th-century Latter-Day Saints colony in San Bernardino, California, was discovered during the construction of a baseball field. Among the remains of 12 individuals recovered from the cemetery were those of a young man of about 22 years, whose burial treatment differed notably from the other intact interments at the site. Unlike these coffin burials, Burial 5 was found in a sprawling position, apparently tossed unceremoniously into the grave pit. Dental morphological traits identified the genetic affinities of this man as Native American, perhaps a member of the local Cahuilla or Serrano tribes, whereas the other individuals appeared to be of European ancestry, an interpretation consistent with records kept by community members. A possible identity for this individual came from a journal account describing the shooting of an “Indian” by the local sheriff, who was then brought to the fort, died, and was buried before his fellow tribesmen arrived to determine what had transpired and perhaps to claim his remains. This chapter explores the identity and life history of this young man in the context of the history of the valley and the pioneer community in which he met his death.

Mechanisms regulating spatial changes in grassland productivity following nutrient addition in northern China

2019 ◽  
Vol 41 (1) ◽  
pp. 83
Author(s):  
Na Zhao ◽  
Xinqing Shao ◽  
Chao Chen ◽  
Jiangwen Fan ◽  
Kun Wang
Keyword(s):  
Functional Traits ◽  
Plant Biomass ◽  
Northern China ◽  
Functional Trait ◽  
Community Response ◽  
Nutrient Addition ◽  
Leymus Chinensis ◽  
Ecosystem Functions ◽  
Natural Grasslands ◽  
Key Species

Plant biomass is the most fundamental component of ecosystems. The spatial stability of plant biomass is important, and the mechanisms regulating plant biomass spatial variability in variable environments are a central focus of ecology. However, they have rarely been explored. We conducted an experiment to test how diversity and functional traits affected variation in biomass and community response to nutrient availability in three plant communities: natural; forb, legume, and bunchgrass; and rhizomatous grass. We found that biomass stability rarely changed with increasing taxonomic species richness and functional group richness but declined with increasing Shannon–Weiner indices (the combination of richness and evenness) and functional trait diversity. However, differences in plant species composition generated different responses in both the amount and spatial variation of biomass following nutrient addition. Because rhizomatous grasses are weakly competitive in nutrient-poor conditions, interaction between resource-acquisitive (grass) and stress-tolerant (forb) species in the natural community conferred the greatest overall stability. The rapid nutrient acquisition ability of the rhizomatous grass Leymus chinensis was stimulated in nutrient-abundant conditions. The functional traits of this dominant species overrode the diversity interaction effects of the natural and forb, legume, and bunchgrass communities. This ultimately resulted in the rhizomatous grass community being the most stable. Community stability was strongly determined by a few key species, particularly rhizomatous grasses, rather than by the average response of all species, thereby supporting the mass ratio hypothesis. Our results indicated that rhizomatous grasses could provide vegetative productivity to reduce soil loss and prevent degradation of L. chinensis-dominant grassland. Thus, protecting specific species is critical for maintaining rangeland ecosystem functions. Moreover, the conservation importance of grasses, non-leguminous forbs, legumes, or even rare species could not be ignored. Maintaining stability mechanisms in natural grasslands is complex, and therefore, further studies need to focus on finding a unified mechanism that can regulate appreciable biomass variation under shifting environmental conditions.

Functional traits and life history diversity of the North Africa endemic Ebenus pinnata Aiton

Flora ◽  
2010 ◽  
Vol 205 (10) ◽  
pp. 666-673 ◽  
Author(s):  
A.K. Hegazy ◽  
H.F. Kabiel ◽  
L. Boulos ◽  
O.S. Sharashy
Keyword(s):  
Life History ◽  
Functional Traits ◽  
North Africa ◽  
The North

scholarly journals Functional traits explain variation in plant life history strategies

2013 ◽  
Vol 111 (2) ◽  
pp. 740-745 ◽  
Author(s):  
P. B. Adler ◽  
R. Salguero-Gomez ◽  
A. Compagnoni ◽  
J. S. Hsu ◽  
J. Ray-Mukherjee ◽  
...  
Keyword(s):  
Life History ◽  
Functional Traits ◽  
Life History Strategies ◽  
Plant Life

scholarly journals A protocol for monitoring plant responses to changing nitrogen deposition regimes in Alberta bogs

2020 ◽  
Vol 192 (11) ◽  
Author(s):  
Dale H. Vitt ◽  
Melissa House ◽  
Samantha Kitchen ◽  
R. Kelman Wieder
Keyword(s):  
Nutrient Loading ◽  
Plant Density ◽  
Annual Growth ◽  
Permanent Plots ◽  
Annual Data ◽  
Oil Sand ◽  
Epiphytic Lichen ◽  
Key Species ◽  
S Deposition ◽  
Sand Extraction

AbstractBogs are nutrient poor, acidic ecosystems that receive their water and nutrients entirely from precipitation (= ombrogenous) and as a result are sensitive to nutrient loading from atmospheric sources. Bogs occur frequently on the northern Alberta landscape, estimated to cover 6% of the Athabasca Oil Sands Area. As a result of oil sand extraction and processing, emissions of nitrogen (N) and sulfur (S) to the atmosphere have led to increasing N and S deposition that have the potential to alter the structure and function of these traditionally nutrient-poor ecosystems. At present, no detailed protocol is available for monitoring potential change of these sensitive ecosystems. We propose a user-friendly protocol that will monitor potential plant and lichen responses to future environmental inputs of nutrients and provide a structured means for collecting annual data. The protocol centers on measurement of five key plant/lichen attributes, including changes in (1) plant abundances, (2) dominant shrub annual growth and primary production, (3) lichen health estimated through chlorophyll/phaeophytin concentrations, (4) Sphagnum annual growth and production, and (5) annual growth of the dominant tree species (Picea mariana). We placed five permanent plots in each of six bogs located at different distances from the center of oil sand extraction and sampled these for 2 years (2018 and 2019). We compared line intercept with point intercept plant assessments using NMDS ordination, concluding that both methods provide comparable data. These data indicated that each of our six bog sites differ in key species abundances. Structural differences were apparent for the six sites between years. These differences were mostly driven by changes in Vaccinium oxycoccos, not the dominant shrubs. We developed allometric growth equations for the dominant two shrubs (Rhododendron groenlandicum and Chamaedaphne calyculata). Equations developed for each of the six sites produced growth values that were not different from one another nor from one developed using data from all sites. Annual growth of R. groenlandicum differed between sites, but not years, whereas growth of C. calyculata differed between the 2 years with more growth in 2018 compared with 2019. In comparison, Sphagnum plant density and stem bulk density both had strong site differences, with stem mass density higher in 2019. When combined, annual production of S. fuscum was greater in 2019 at three sites and not different at three of the sites. Chlorophyll and phaeophytin concentrations from the epiphytic lichen Evernia mesomorpha also differed between sites and years. This protocol for field assessments of five key plant/lichen response variables indicated that both site and year are factors that must be accounted for in future assessments. A portion of the site variation was related to patterns of N and S deposition.

Differences in disturbance type and nutrient availability favour different functional traits across three co-occurring montane wetland systems in eastern Australia

2016 ◽  
Vol 64 (6) ◽  
pp. 526 ◽  
Author(s):  
John T. Hunter
Keyword(s):  
Life History ◽  
Seed Size ◽  
Functional Traits ◽  
Nutrient Availability ◽  
Vascular Plant ◽  
Fruit Size ◽  
Functional Trait ◽  
Freshwater Wetland ◽  
Disturbance Regime ◽  
Eastern Australia

Three co-occurring temperate montane non-riparian freshwater wetland communities of the New England Batholith of eastern Australia were chosen to test differences in resource allocation to select functional traits. Each of the wetlands was tested against inferred gradients of nutrient availability, fire and disturbance frequency. Collated functional trait data on 563 native vascular plant taxa known to occur in bogs, fens and lagoons were used against a centrally weighted means redundancy analysis. Traits included life form, plant height, leaf area, fruit size, seed size, mono- or polycarpy, storage organs, fruit type, vegetative spread and geographic range size. Where disturbances were moderate to low in frequency and habitats persistent, tolerance and in-situ permanence traits were favoured. With high nutrient availability and a low disturbance regime polycarpic species with large leaves that allow for larger fruit development were more common. Under low nutrient availability and a moderate disturbance regime, persistence was shifted to a longer lived polycarpic life history that includes woody taxa with increased seed size and a greater diversity of fruit types. In frequently inundated habitats, with shifting windows of available habitats, avoidance was the best strategy. Here persistence shifts to long-lived soil stored diaspores and a monocarpic life history with rapid vegetative growth to capture above ground spatial resource within temporary habitats.

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