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V H Resh

Publications and source records attributed to V H Resh.

6 recordsLinked to original sources
PubMed2001

Species traits and environmental constraints: entomological research and the history of ecological theory.

The role that entomology has played in the historical (1800s-1970s) development of ecological theories that match species traits with environmental constraints is reviewed along three lineages originating from the ideas of a minister (Malthus TR. 1798. An Essay on the Principle of Population. London: Johnson) and a chemist (Liebig J. 1840. Die Organische Chemie in ihrer Anwendung auf Agricultur und Physiologie. Braunschweig: Vieweg). Major developments in lineage 1 focus on habitat as a filter for species traits, succession, nonequilibrium and equilibrium conditions, and generalizations about the correlation of traits to environmental constraints. In lineage 2, we trace the evolution of the niche concept and focus on ecophysiological traits, biotic interactions, and environmental conditions. Finally, we describe the conceptual route from early demographic studies of human and animal populations to the r-K concept in lineage 3. In the 1970s, the entomologist Southwood merged these three lineages into the "habitat templet concept" (Southwood TRE. 1977. J. Anim. Ecol. 46:337-65), which has stimulated much subsequent research in entomology and general ecology. We conclude that insects have been a far more important resource for the development of ecological theory than previously acknowledged.

Animals↗
PubMed1992

Wetland management strategies that enhance waterfowl habitats can also control mosquitoes.

Two studies in California wetlands and a third in Minnesota wetlands indicate that management practices designed to enhance habitat quality for waterfowl can concurrently reduce mosquito problems. In a seasonally flooded pickleweed wetland in Suisun Marsh, Solano Co., CA, we demonstrated that reducing plant-cover by 50% increased benthic densities of chironomid midge and dytiscid beetle larvae; these insects can be important in waterfowl diets. This manipulation also concentrated Aedes melanimon and Culiseta inornata mosquito larvae along wetland perimeters; thus, the need for control measures was greatly restricted spatially. A study in 9 experimental ponds in Suisun Marsh demonstrated that higher water levels could enhance populations of the macroinvertebrates important in waterfowl diets; general macroinvertebrate densities were higher at 60 cm depths than 20 cm or 40 cm depths. In contrast, Cs. inornata densities were lowest at 60 cm depths and highest at 20 cm depths. A study conducted in a perennial-water cattail wetland in Minneapolis-St. Paul, MN, demonstrated that a temporary water-level drawdown, designed to enhance waterfowl habitat quality of perennial-water wetlands, also reduced densities of Coquillettidia perturbans mosquito larvae. These mosquitoes disappeared immediately after the drawdown, but even after water depths were restored to pre-drawdown levels, significant numbers did not reappear until 4 years post-drawdown. Studies in 202 other Minnesota wetlands also demonstrated the susceptibility of Cq. perturbans populations to drawdown, but the impact of drawdown was greater in stands of emergent cattail than in floating cattail.

Aedes↗
PubMed1991

Where is mosquito research published?

To identify the core journals that publish articles on mosquito research, the Agricola database (covering 1985-89 citations) was analyzed. This source contained 3,007 citations to mosquito research, and the citations were found in 404 different serials. Whereas 10 serials (2.5% of total serials) in Agricola produced 50% of the citations, almost one-half of the serials in this source contained only one citation to mosquito research. Fifteen journals (the core journals) contained greater than 1% of total citations. The number of citations found among 126 different databases and abstracting services that were examined varied: 39 had no citations to mosquitoes, but 13 (including life-sciences, medical and even popular-literature databases) had greater than 100 citations. The choice of core journals will be an increasingly important decision by biological libraries as costs for journal subscriptions rise.

Animals↗
PubMed1989

Experimental test of the influence of aquatic macrophyte cover on the survival of Anopheles larvae.

Emergent or submergent macrophytes can enhance the survival of Anopheles larvae by providing favorable microhabitat and refuge from predation. The relationships among the amount of aquatic macrophyte cover, the density of Gambusia affinis, and survivorship of Anopheles freeborni larvae were tested experimentally. Larval survivorship was positively related to amount of plant cover and negatively related to Gambusia density. Larval survivorship was lowest in treatments with low plant cover and high fish density (0-15% survivorship) and highest in treatments with high plant cover and no fish (41-76% survivorship). Similar patterns of larval survivorship were found in enclosure experiments conducted at 3 sites, using 3 species of aquatic macrophytes (Potamogeton pectinatus, Myriophyllum aquaticum and M. spicatum).

Animals↗