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You searched for: Journal Ecology Remove constraint Journal: Ecology Publication Year 1974 Remove constraint Publication Year: 1974 Source 1974 v.55 no.4 Remove constraint Source: 1974 v.55 no.4
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1. A Simple Method for the Dry Combustion of 14C‐Labeled Materials

Author:
Burnison, B. Kent; Perez, Kenneth T.
Source:
Ecology 1974 v.55 no.4 pp. 899-902
ISSN:
0012-9658
Subject:
carbon; chloroform; combustion; insect larvae; radionuclides
Abstract:
... Current methods for the determination of radioactive carbon in samples of biological material are either expensive, elaborate, dangerous, time consuming, or subject to contamination. A simple and inexpensive method is described here which eliminates these disadvantages and allows for the determination of 14C—activity in simple (14C—glucose) or complex (chloroform extract of ground 14C—labeled wax ...
DOI:
10.2307/1934429

2. A Solid State pH Control System for Algal Culturing and Uptake Studies

Author:
Sperling, Jon A.; Grunewald, Ralph; Dovala, Donald
Source:
Ecology 1974 v.55 no.4 pp. 895-898
ISSN:
0012-9658
Subject:
Mastigocladus laminosus; air; algae; carbon dioxide; culture media; isotopes; pH; sodium hydroxide; trichomes
Abstract:
... An inexpensive solid state pH control circuit was built for external use with existing pH meters that can use either a gas or a liquid solution for pH control of culture media. Mastigocladus laminosus showed a 49% reduction in the rate of radiophosphate (P—32) uptake between gas—controlled (30% CO₂ in air) pH intervals of 8.7 (optimal uptake) and 5.7. Isotope uptake rates at higher pH values (achi ...
DOI:
10.2307/1934428

3. Behavioral and Environmental Factors in the Spatial Distribution and Popualtion Dynamics of a Yellow‐Bellied Marmot Population

Author:
Svendsen, Gerald E.
Source:
Ecology 1974 v.55 no.4 pp. 760-771
ISSN:
0012-9658
Subject:
Marmota; burrows; environmental factors; females; habitats; population distribution; population dynamics; reproductive fitness; satellites; social behavior; social structure; Colorado
Abstract:
... Behavioral and environmental factors in the spatial distribution and population dynamics of a yellow—bellied marmot (Marmota flaviventris) population were studied in 1971 and 1972 in Gunnison Co., Colorado. Yellow—bellied marmots are generally considered to be colonial; however, this is not their only option, depending upon the marmots' behavioral profile and the size and composition of the habita ...
DOI:
10.2307/1934412

4. Caloric, Elemental, and Nutritive Changes in Decomposing Juncus Roemerianus Leaves

Author:
de la Cruz, Armando A.; Gabriel, Benjamin C.
Source:
Ecology 1974 v.55 no.4 pp. 882-886
ISSN:
0012-9658
Subject:
Juncus roemerianus; carbon; containers; crude fiber; energy content; leaves; lipids; nitrogen; oxygen; phosphorus; plant tissues; protoplasm; respiratory rate
Abstract:
... In situ decomposition rate of Juncus roemerianus (Juncaceae) leaves determined by litterbag method was 40% per year. Caloric, elemental, and proximate nutritive analyses of leaves at various stages of life and decay–classified as young, mature, standing dead, partially decayed, decomposed fragments, and particulate detritus–showed the following: (a) an increase in caloric content (4630—4911 g cal/ ...
DOI:
10.2307/1934425

5. Colonization Curves for Planar Marine Islands

Author:
Schoener, Amy
Source:
Ecology 1974 v.55 no.4 pp. 818-827
ISSN:
0012-9658
Subject:
fouling; islands; models; seasonal variation; temperature
Abstract:
... Marine fouling and successional studies, documenting species changes on flat, isolated objects, provide some additional data on island colonization. Plotting numbers of species on these planar islands over time allows construction of several colonization curves. Contrary to the MacArthur—Wilson equilibrium model, in many cases these curves do not convincingly approach an equilibrium number of spec ...
DOI:
10.2307/1934417

6. Creation of Relatively Stable Shrublands with Herbicides: Arresting "Succession" on Rights‐of‐Way and Pastureland

Author:
Niering, William A.; Goodwin, Richard H.
Source:
Ecology 1974 v.55 no.4 pp. 784-795
ISSN:
0012-9658
Subject:
Gaylussacia baccata; Smilax; Vaccinium; arboreta; botanical composition; clones; forests; graminoids; habitat conservation; hardwood; herbicides; landscaping; pastures; rights of way; shrublands; shrubs; tree growth; trees; wildlife habitats; Connecticut
Abstract:
... Two decades of selective—use herbicide management on a demonstration right—of—way within the Connecticut Arboretum has resulted in a mosaic of relatively stable shrub communities and less stable herblands within the central hardwoods forest region. Areas of continuous dense shrub cover have resisted tree invasion for at least 15 yr. On abandoned pastureland shrub clones of Gaylussacia baccata, Smi ...
DOI:
10.2307/1934414

7. Developmental Control of Net Productivity in Typha Latifolia Ecotypes

Author:
McNaughton, S. J.
Source:
Ecology 1974 v.55 no.4 pp. 864-869
ISSN:
0012-9658
Subject:
Typha latifolia; acclimation; biomass production; carbon; climate; dry matter accumulation; ecotypes; environmental factors; leaves; net assimilation rate
Abstract:
... Population samples of broad—leaved cattail (Typha latifolia L.) from a variety of climates were studied to determine the extent to which net productivity, as dry matter production rate, was determined by (a) net assimilation rate per unit left tissue and (b) rate of production of leaf tissue. Assimilation rates of the eight populations studied were identical. Similarly, acclimation responses stabi ...
DOI:
10.2307/1934422

8. Effects of Salinity on Growth of Several Aquatic Macrophytes

Author:
Haller, William T.; Sutton, D. L.; Barlowe, W. C.
Source:
Ecology 1974 v.55 no.4 pp. 891-894
ISSN:
0012-9658
Subject:
Azolla caroliniana; Eichhornia crassipes; Hydrilla verticillata; Lemna minor; Myriophyllum aquaticum; Myriophyllum spicatum; Najas; Pistia stratiotes; Salvinia auriculata; Vallisneria americana; greenhouse production; macrophytes; plant response; root growth; salinity; sodium chloride; toxicity; transpiration
Abstract:
... Growth rates of 10 aquatic macrophytes in various salinities under greenhouse conditions varied widely. Salt concentrations of 1.66% and 2.5% were toxic to Pistia stratiotes L. and Eichornia crassipes (Mart.) Solms, respectively. Salinities of 16.65% or higher were toxic to Lemna minor L., but growth of Lemna was increased by salt concentrations of 0.83%, 1.66%, 2.50%, and 3.33% as compared to oth ...
DOI:
10.2307/1934427

9. Energy Requirements of a Population of Pinfish Lagodon Rhomboides (Linnaeus)

Author:
Hoss, Donald E.
Source:
Ecology 1974 v.55 no.4 pp. 848-855
ISSN:
0012-9658
Subject:
Lagodon rhomboides; adults; biomass; energy; energy requirements; estuaries; fish; juveniles; larvae; metabolism; primary productivity; rivers; trophic relationships; North Carolina
Abstract:
... Biomass and rates of metabolism were estimated for a population of pinfish in the Newport River estuary, North Carolina. This information was used to estimate the routine energy requirements of the pinfish population and to relate these energy requirements to primary productivity in the estuary. Population estimations of larval, juvenile, and adult pinfish were made over a 2—yr period. Peak biomas ...
DOI:
10.2307/1934420

10. Estimation of Energy Flow in Bird Communities: A Population Bioenergetics Model

Author:
Wiens, John A.; Innis, George S.
Source:
Ecology 1974 v.55 no.4 pp. 730-746
ISSN:
0012-9658
Subject:
adults; age structure; ambient temperature; biomass; birds; body weight; breeding; breeding season; clutch size; digestion; egg production; energy costs; energy flow; energy metabolism; energy requirements; fledglings; juveniles; migratory behavior; molting; mortality; phenology; population density; simulation models
Abstract:
... We describe a simulation model that estimates population density flux, biomass changes, and bioenergetic demands of bird populations, especially with reference to the breeding season. changes in the population density of adults of each species considered were calculated from breeding census values and information on migratory movements. Using field or literature values for clutch size, mortality r ...
DOI:
10.2307/1934410

11. Fallout 137CS in the Soils and Sediments of Three Small Watersheds

Author:
Ritchie, Jerry C.; McHenry, J. Roger; Gill, Angela C.
Source:
Ecology 1974 v.55 no.4 pp. 887-890
ISSN:
0012-9658
Subject:
cropland; crops; eroded soils; forests; grasses; sediments; watersheds; Mississippi
Abstract:
... A budget for the distribution of fallout ¹ ³ ⁷Cs was calculated for three small watersheds in northern Mississippi. The cover in one contributing watershed is predominantly forest, in the second it is predominantly grass, and in the third predominantly grass and crops. Of the total ¹ ³ ⁷Cs input, 97%, 88%, and 85%, respectively, remained in the forest, the grass, and the grass—crop watersheds. The ...
DOI:
10.2307/1934426

12. Feeding Ecology of a Temperate Insectivorous Bat (Myotis Velifer)

Author:
Kunz, Thomas H.
Source:
Ecology 1974 v.55 no.4 pp. 693-711
ISSN:
0012-9658
Subject:
Coleoptera; Lepidoptera; Myotis; adults; autumn; body weight; diet; eating habits; eclosion; energy; flight; food availability; food consumption; foraging; insectivores; intraspecific competition; juveniles; lactating females; lactation; males; milk; molting; moths; pregnancy; seasonal variation; spermatogenesis; spring; stomach; summer; Kansas
Abstract:
... The feeding behavior and ecology of the cave bat, Myotis velifer, in south—central Kansas are investigated. Emergence behavior and foraging patterns varied according to sex, age, reproductive condition, season, and colony size. Females had one synchronous period of departure in late states of pregnancy. Two feeding periods usually were evident in summer with a major period of activity soon after s ...
DOI:
10.2307/1934408

13. Genetic and Social Structure of Feral House Mouse Populations on Grizzly Island, California

Author:
Myers, Judith H.
Source:
Ecology 1974 v.55 no.4 pp. 747-759
ISSN:
0012-9658
Subject:
Mus musculus; environmental factors; esterases; farm buildings; females; feral animals; gene frequency; genotype; grasslands; hemoglobin; loci; mice; reproduction; sexual maturity; social structure; trapping; California
Abstract:
... Two populations of house mice living in open grassland in northern California were tested for demic structure, which has been reported for populations living in farm buildings. Mice captured in each of two 0.8—ha trapping areas were typed for two blood proteins (hemoglobin and an esterase). Nonrandom distributions of genotypes within the populations occasionally occurred, but were not temporally s ...
DOI:
10.2307/1934411

14. Genetic, Photic and Temperature Effects on the Fecundity of Tribolium

Author:
Hawk, James A.; Colaianne, J. J.; Bell, A. E.
Source:
Ecology 1974 v.55 no.4 pp. 910-912
ISSN:
0012-9658
Subject:
Tribolium castaneum; eggs; fecundity; genotype; genotype-environment interaction; lighting; temperature
Abstract:
... Fecundity of two unrelated populations of Tribolium castaneum as measured by eggs laid and hatchability was studied in a factorial design involving two levels of temperature (28°C vs. 33°C) and of lighting (light vs. dark). Significant differences between genotype, temperatures, and lighting regimes were observed for egg numbers, whereas temperature represented the only significant influence on ha ...
DOI:
10.2307/1934432

15. Growth in Artificial Climates‐‐An Indication of Mimulus' Ability to Invade New Habitats

Author:
Vickery, Robert K., Jr.
Source:
Ecology 1974 v.55 no.4 pp. 796-807
ISSN:
0012-9658
Subject:
Mimulus; climate; genotype; habitats; hybridization; lighting; photoperiod; temperature
Abstract:
... Minulus guttatus and its related species have adaptable genotypes that enabled each plant to grow in a wide range of climates. The growth of the clone members of the plants differed significantly from group to partially—overlapping group of climates. The group of optimal climates had moderate day temperatures with cool nights, high illumination, and long day photoperiods of 16 hr. Overall the plan ...
DOI:
10.2307/1934415

16. Growth Rates of Young Passerines and the Flexibility of Clutch Size

Author:
Fretwell, Stephen D.; Bowen, Daniel E.; Hespenheide, Henry A.
Source:
Ecology 1974 v.55 no.4 pp. 907-909
ISSN:
0012-9658
Subject:
Passeriformes; clutch size; mortality; nests
Abstract:
... This note clarifies and amplifies Ricklefs' (1968) demonstration that the growth period for passerines laying a small clutch has a wider range than for those laying larger clutches. We show that his argument does not distinguish between food— and predator—limited clutch size theories, and that the theoretical variances predicted by Ricklefs do not follow from his assumptions. We extend the theory ...
DOI:
10.2307/1934431

17. Growth Rings: Annual Periodicity in Two Gorgonian Corals

Author:
Grigg, Richard W.
Source:
Ecology 1974 v.55 no.4 pp. 876-881
ISSN:
0012-9658
Subject:
age determination; corals; equations; growth rings; periodicity
Abstract:
... Comparison of the number of growth rings present in the skeletons of colonies of two gorgonian corals, Muricea californica and M. fruticosa, with estimates of their age based on observed growth rates indicates that the periodicity of ring formation is annual. Data from two other methods used to determine periodicity support this conclusion. The results indicate that the observed growth of these go ...
DOI:
10.2307/1934424

18. Habitat Selection of Breeding Birds in an East Tennessee Deciduous Forest

Author:
Anderson, Stanley H.; Shugart, Herman H., Jr.
Source:
Ecology 1974 v.55 no.4 pp. 828-837
ISSN:
0012-9658
Subject:
Paridae; Parulidae; Picidae; Thraupidae; analysis of variance; breeding; deciduous forests; discriminant analysis; habitat destruction; habitat preferences; habitats; prediction; saplings; watersheds; woodpeckers; Tennessee
Abstract:
... Bird populations were sampled between May 30 and July 20, 1972, on twenty—four 0.08—ha plots on Walker Branch Watershed, a primarily deciduous forest located in Anderson County, Tennessee. Univariate analysis of variance was used to test for differences in abundance categories of each bird species with respect to 28 habitat variables. Differences in habitat preferences within major bird families ( ...
DOI:
10.2307/1934418

19. Loss of Prey Body Contents during Feeding by an Aquatic Predator

Author:
Dagg, Michael J.
Source:
Ecology 1974 v.55 no.4 pp. 903-906
ISSN:
0012-9658
Subject:
Amphipoda; gravimetry; ingestion; mastication
Abstract:
... During the feeding process of the grasping and chewing amphipod Calliopius laeviusculus, a significant portion of the prey body contents is lost to the surrounding water. The amount of material lost decreases as the size of the predator increases. If this loss is ignored in ingestion studies, the result is a substantial overestimation of assimilation and assimilation efficiency, as determined by t ...
DOI:
10.2307/1934430

20. Phenological Events and Their Environmental Triggers in Mojave Desert Ecosystems

Author:
Beatley, Janice C.
Source:
Ecology 1974 v.55 no.4 pp. 856-863
ISSN:
0012-9658
Subject:
annuals; autumn; ecosystems; growing season; perennials; rain; reproduction; shrubs; spring; trophic relationships; winter; Mojave Desert; Nevada
Abstract:
... Phenological events in Mojave desert systems are triggered by heavy rains (>25 mm [1 in]). The most predictable and consequential of these is a regional rain between late September and early December. This rainfall event is usually the precursor of successful vegetative and reproductive growth of shrubs the next spring, and is usually necessary for all growth phenomena of herbaceous perennials and ...
DOI:
10.2307/1934421