We use Wiens' (1984) nonequilibrium-equilibrium continuum concept to evaluate aspects of community structure for sawfly herbivores (Hymenoptera: Tenthredinidae) that attack arroyo willow, Salix lasiolepis. The sawfly community on arroyo willow shares many characteristics of nonequilibrium communities: unsaturation, biotic decoupling, lack of density dependence, and loose emergent patterns. Species abundances exhibit highly significant differences among clones (P<0.001) and among years (P<0.001) and exhibit significant and complex clone-by-year interactions both for absolute and relative abundances. Organizing forces, such as interspecific competition and regulation by natural enemies, are largely absent from the arroyo willow system. Sawfly densities exhibit significant positive covariation among willow clones and appear to be affected by largely stochastic abiotic forces, primarily winter precipitation.
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http://dx.doi.org/10.1007/BF00323759 | DOI Listing |
J Hazard Mater
March 2023
Planta Piloto de Procesos Industriales Microbiológicos (PROIMI-CONICET), Avenida Belgrano y Pasaje Caseros, 4000 Tucumán, Argentina; Facultad de Ciencias Naturales e IML, Universidad Nacional de Tucumán (UNT), Miguel Lillo 205, 4000, Tucumán, Argentina. Electronic address:
Glyphosate (Gly) and its principal degradation product, the aminomethylphosphonic acid (AMPA) were found in soils from a riparian environment in Argentina. Sixty-five actinobacteria were isolated from these soils, rhizosphere, and plants (Festuca arundinacea and Salix fragilis). The isolate Streptomyces sp.
View Article and Find Full Text PDFPeerJ
May 2019
California Water Quality Control Board, San Diego Region, San Diego, CA, USA.
The Kuroshio Shot Hole Borer (KSHB, ) and the Polyphagous Shot Hole Borer (; Coleoptera: Curculionidae: Scolytinae) have recently invaded southern California and are attacking live trees in commercial agriculture groves, urban parks and native riparian forests. Among native forests the worst impacts observed to date have been in the Tijuana River Valley in south San Diego County, where approximately 30% of the native willows ( spp.), or 120,000 trees, have died as a result of a KSHB infestation.
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July 2016
Southwest Wetlands Interpretive Association , Imperial Beach , CA , United States.
The Tijuana River Valley is the first natural habitat in California to be substantially invaded by the Kuroshio Shot Hole Borer (KSHB, Euwallacea sp.), an ambrosia beetle native to Southeast Asia. This paper documents the distribution of the KSHB in the riparian vegetation in the valley and assesses the damage done to the vegetation as of early 2016, approximately six months after the beetle was first observed in the valley.
View Article and Find Full Text PDFEnviron Entomol
June 2015
Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109.
The interaction between the arroyo willow, Salix lasiolepis Bentham, and its specialist herbivore, the arroyo willow stem-galling sawfly, Euura lasiolepis Smith (Hymenoptera: Tenthredinidae), was studied for 32 yr in Flagstaff, AZ, emphasizing a mechanistic understanding of insect population dynamics. Long-term weather records were evaluated to provide a climatic context for this study. Previously, predictive models of sawfly dynamics were developed from estimates of sawfly gall density made between 1981 and 2002; one model each for drier and wetter sites.
View Article and Find Full Text PDFSci Total Environ
February 2015
Departamento de Biodiversidad y Gestión Ambiental, Universidad de León, Campus de Vegazana s/n, CP 24071, León, Spain. Electronic address:
Bacteria are key players in wetland ecosystems, however many essential aspects regarding the ecology of wetland bacterial communities remain unknown. The present study characterizes soil bacterial communities from natural and constructed wetlands through the pyrosequencing of 16S rDNA genes in order to evaluate the influence of wetland variables on bacterial community composition and structure. The results show that the composition of soil bacterial communities was significantly associated with the wetland type (natural or constructed wetland), the type of environment (lagoon, Typha or Salix) and three continuous parameters (SOM, COD and TKN).
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