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You searched for: Journal Ecology Remove constraint Journal: Ecology Publication Year 1967 Remove constraint Publication Year: 1967 Source 1967 v.48 no.1 Remove constraint Source: 1967 v.48 no.1
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1. A Pressure‐Infiltration Method for Estimating Stomatal opening in Conifers

Author:
Fry, Kenneth E.; Walker, Richard B.
Source:
Ecology 1967 v.48 no.1 pp. 155-157
ISSN:
0012-9658
Subject:
Pseudotsuga menziesii; conifer needles; conifers; porosity; stomata; stomatal movement; transpiration
Abstract:
... A method is presented for estimating large and small changes of stomatal aperture in conifer needles by means of partial infiltration of alcoholic fluids under pressure. Needles are placed in a small, widowed chamber and are observed while the pressure is increased. Minute reflections of light which emanate from the stomata indicate the specific pressure at which infiltration begins. In theory thi ...
DOI:
10.2307/1933428

2. A Rapid Method for Estimating Arboreal Canopy Cover

Author:
Emlen, John T.
Source:
Ecology 1967 v.48 no.1 pp. 158-160
ISSN:
0012-9658
Subject:
canopy; rapid methods; savannas; trees; woodlands
Abstract:
... The per cent of a tract of savannah or woodland that is covered by tree canopy is measured by point quadrat sampling along a series of straight line transects using a vertical viewing tube. ...
DOI:
10.2307/1933429

3. Color Stereophotography for the Measurement of Vegetation

Author:
Wimbush, D. J.; Barrow, M. D.; Costin, A. B.
Source:
Ecology 1967 v.48 no.1 pp. 150-152
ISSN:
0012-9658
Subject:
cameras; color; glass; ground vegetation; legs; paper; photographs; photography; prisms; vegetation
Abstract:
... The field equipment needed for a stereophographic method of measurement of vegetation consists of a camera mounted on a rectangular frame on four legs, from which a stereo pair of photographs of the ground or vegetation surface can be taekn. For color transparencies the stereo pair of images is projected upwards through two specially mounted projectors and prisms onto tracing paper on a glass tabl ...
DOI:
10.2307/1933426

4. Comparative Efficiencies of Van Veen and Smith‐McIntyre Grab Samplers as Revealed by Motion Pictures

Author:
Wigley, Roland L.
Source:
Ecology 1967 v.48 no.1 pp. 168-169
ISSN:
0012-9658
Subject:
animals; benthic organisms; jaws; samplers; standard operating procedures
Abstract:
... Two commonly used benthos samplers, van Veen and Smith—McIntyre, were tested to detect possible adverse characteristics for sampling epibenthic animals. A strong hydraulic disturbance (shock wave) was formed below the van Veen sampler as it descended through the water toward bottom. In this sampler the shock wave was sufficiently strong to force aside unattached benthic animals as long as 8 cm. Th ...
DOI:
10.2307/1933432

5. Dynamics of Popualations. II. Factors Controlling Population Growth and Population Size in Drosophilia Pseudoobscura and in Drosophila Melanogaster

Author:
Ayala, Francisco Jose
Source:
Ecology 1967 v.48 no.1 pp. 67-75
ISSN:
0012-9658
Subject:
Drosophila melanogaster; Drosophila pseudoobscura; biomass; carrying capacity; environmental factors; heterozygosity; homozygosity; longevity; population growth; population size; temperature
Abstract:
... Four populations of Drosophila pseudoobscura and four of D. melanogaster were studied for the influence of certain environmental factors on the productivity and size of the populations. For each species a 2 x 2 factorial design was used, the variables being temperature (25°C and 19°C) and amount of food (2 and 3 food unites per week). A serial transfer technique was used to maintain the population ...
DOI:
10.2307/1933418

6. Ecology of Zooplankton of the Cape Thompson Area Alaska

Author:
Tash, Jerry C.; Armitage, Kenneth B.
Source:
Ecology 1967 v.48 no.1 pp. 129-139
ISSN:
0012-9658
Subject:
Cladocera; Copepoda; aquatic habitat; autumn; brackish water; community structure; eggs; energy; females; lakes; lipids; physicochemical properties; primary productivity; surveys; winter; zooplankton; Alaska
Abstract:
... In a survey of the physicochemical characteristics, primary productivity and occurrence of zooplankton in fresh and brackish waters of Cape Thompson, Alaska, between June 28, 1960 and August 7, 1961, 14 species of Cladocera and 38 species of Copepoda (13 Calanoida, 11 Cyclopoida and 14 Harpacticoida) were distinguished in collections from 10 lakes, 8 lagoons and 111 pools. Seventy—three percent of ...
DOI:
10.2307/1933424

7. Factors Affecting the Distribution of Shrub Live Oak (Quercus Turbinella Greene)

Author:
Saunier, R. E.; Wagle, R. F.
Source:
Ecology 1967 v.48 no.1 pp. 35-41
ISSN:
0012-9658
Subject:
Quercus turbinella; chaparral; clay soils; diorite; drought; grasslands; quartz; reproduction; rooting; sediments; seedling production; shrubs; soil water; Arizona
Abstract:
... The disjunct distribution, reproduction, and rooting habits of Quercus turbinella in the Arizona chaparral were studied on quartz diorite, sedimentary, and volcanic substrata. The oak was less dense on the sediments and volcanics that on quartz diorite. Lower densities on the bedded sediments resulted from restricted root penetration which prevented access to deep soil moisture; on the volcanic su ...
DOI:
10.2307/1933415

8. Fire, Vegetation Structure, and the Ant X Acacia Interaction in Central America

Author:
Janzen, Daniel H.
Source:
Ecology 1967 v.48 no.1 pp. 26-35
ISSN:
0012-9658
Subject:
Acacia; Formicidae; ant colonies; evolution; fires; lowlands; shoots; stumps; vegetation; vegetation structure; Central America
Abstract:
... The effect of fire on swollen—thorn acacias and their tenant obligate acacia—ants in the Central American dry lowlands is discussed. Fires may either consume the entire acacia shoot and ant colony, scorch and kill the acacia but not the ants, or kill neither acacia nor ant colony. Which alternative occurs depends on the structure of the immediately surrounding vegetation which in turn depends on h ...
DOI:
10.2307/1933414

9. Food, Age, and the Dynamics of a Laboratory Population of Rotifers

Author:
King, Charles E.
Source:
Ecology 1967 v.48 no.1 pp. 111-128
ISSN:
0012-9658
Subject:
Chlamydomonas reinhardtii; Euglena gracilis; Rotifera; algae; animals; clones; death; eggs; females; food intake; foods; oviposition; parents; parthenogenesis; population density; population growth; survival rate
Abstract:
... Two clones of the rotifer Euchlanis dilatata were derived from a single parent by parthenogenesis so that in succeeding generations the individuals of one clone (the young orthoclone) were always derived from young parents and those of the other (the old orthoclone) from old parents. These clones were fed four different food concentrations (1.6, 4.9, 16.4, and 49.2 mg/ml) of three different algal ...
DOI:
10.2307/1933423

10. Foraging Relationships of Brown‐Headed Nuthatches and Pine Warblers

Author:
Morse, Douglass H.
Source:
Ecology 1967 v.48 no.1 pp. 94-103
ISSN:
0012-9658
Subject:
Poecile carolinensis; Sitta; autumn; bark; branches; flocks; foraging; habitats; seeds; winter; Louisiana
Abstract:
... Foraging behavior and interactions between Brown—headed Nuthatches (Sitta pusilla) and Pine Warblers (Dendroica pinus) were studied in longleaf pine lands of Louisiana during the fall and winter of 1963—64 and 1964—65. Both species frequently were members of flocks that formed around Carolina Chickadees (Parus carolinensis) and Tufted Titmice (P. bicolor). Most contact between the former two speci ...
DOI:
10.2307/1933421

11. Forb‐Arthropod Food Chains in a One‐Year Experimental Field

Author:
Wiegert, Richard G.; Odum, Eugene P.; Schnell, Jay H.
Source:
Ecology 1967 v.48 no.1 pp. 75-83
ISSN:
0012-9658
Subject:
Aphidoidea; Conyza canadensis; Dorymyrmex; Erigeron; Heterotheca subaxillaris; Oecanthus; fauna; field experimentation; food chain; grazing intensity; isotopes; phytophagous insects; predation; radionuclides; weeds; South Carolina
Abstract:
... Phosphorous—32 tracer studies of plant—arthropod food chains showed a significant difference in both consumer diversity and grazing pressure between the two dominant plant species on a first—year weed field in South Carolina. Where Heterotheca subaxillaris was the labeled plant ³ ²P was transferred readily to a number of phytophagous insects and secondarily to the predator fauna. Where only Eriger ...
DOI:
10.2307/1933419

12. Nutrition of Tree Sparrows during Winter in Central Illinois

Author:
West, George C.
Source:
Ecology 1967 v.48 no.1 pp. 58-67
ISSN:
0012-9658
Subject:
Passer montanus; Spizella; birds; combustion; diet; energy content; energy requirements; flocks; grasses; heat; seeds; stomach; traps; tree nutrition; winter; Illinois
Abstract:
... Stomach analyses of 131 tree sparrows (Spizella arborea) were made from birds collected from November through March, 1954—1959, near Urbana in Champaign County, Illinois. Simultaneously, 119 collections of seeds from the ground and 452 collections of seeds falling into seed traps were taken and the dry weight in grams per hectare per winter and the relative proportion of different species of seeds ...
DOI:
10.2307/1933417

13. Population Dynamics of the Walnut Aphid, Chromaphis Juglandicola (KALT.) in Northern California

Author:
Sluss, R. R.
Source:
Ecology 1967 v.48 no.1 pp. 41-58
ISSN:
0012-9658
Subject:
Chromaphis juglandicola; Coleoptera; carrying capacity; insects; irrigation; orchards; parasitism; population growth; predation; predators; spring; temperature; trees; vigor; walnuts; California
Abstract:
... Populations of waln ut aphids and associated insects were observed over a four year period in several northern California walnut orchards. Temperature, leaflet age, amount of prior aphid feeding and coccinellid predation were found to be the most important factors influencing walnut aphid population changes. Sharp declines in aphid population levels were correlated with high temperatures, especial ...
DOI:
10.2307/1933416

14. Preliminary Experiments on Physical Tolerances of Eggs of Lizards and Snakes

Author:
Fitch, Henry S.; Fitch, Alice V.
Source:
Ecology 1967 v.48 no.1 pp. 160-165
ISSN:
0012-9658
Subject:
Elaphe; absorption; developmental stages; eggs; humans; limestone; lizards; mortality; relative humidity; sand; snakes; temperature; water content; weight gain; wood; Great Plains region
Abstract:
... In lizards and snakes the egg is a vulnerable stage in the life cycle with limitations that must often restrict geographic range or local occurrence of a species. Eggs of the rat snake, racer, ring—necked snake, Great Plains skink and five—linked skink were exposed in mixed groups to various controlled conditions of temperature and humidity to determine some of the differences between species in t ...
DOI:
10.2307/1933430

15. Prompt Transfers of Cesium‐137 to the Soils of a Tagged Liriodendron Forest

Author:
Waller, H. D.; Olson, J. S.
Source:
Ecology 1967 v.48 no.1 pp. 15-25
ISSN:
0012-9658
Subject:
Liriodendron tulipifera; canopy; death; exudation; forest litter; forests; growing season; income; inventories; leaching; leaves; mineral soils; rain; roots; soil sampling; soil solution; stems; tree trunk; trees
Abstract:
... An inventory of total Cs¹ ³ ⁷ distribution in a 500—m² tagged tulip poplar (Liriodendron tulipifera) forest at the Oak Ridge National Laboratory showed transfer from trees to soil during the first growing season. About one—third of the maximum amount of radiocesium found in the tree canopy during June was transferred to the forest floor and soil; the remainder moved back into woody tissue (stem an ...
DOI:
10.2307/1933413

16. Relative Movements of Lizards in Natural Populations as Determined from Recapture Radii

Author:
Tinkle, Donald W.; Woodward, Donald W.
Source:
Ecology 1967 v.48 no.1 pp. 166-168
ISSN:
0012-9658
Subject:
females; lizards; males; social behavior
Abstract:
... The mean recapture radius has been shown to be an accurate measure of the degree of movements in populations of the lizard Uta stansburiana. It is relatively constant for differing numbers of captures, different numbers of individuals, different years in the same study area and for different periods of time. It is sensitive to density with which it varies inversely. Differences in the mean recaptu ...
DOI:
10.2307/1933431

17. Role of Allochthonous Detritus in the Trophic Structure of a Woodland Springbrook Community

Author:
Mninshall, G. Wayne
Source:
Ecology 1967 v.48 no.1 pp. 139-149
ISSN:
0012-9658
Subject:
Bacillariophyceae; Gammarus; benthic organisms; carnivores; crops; diet; digestive system; fauna; foods; herbivores; invertebrates; leaves; omnivores; particulate organic matter; primary energy; stream channels; stream flow; woodlands; Kentucky
Abstract:
... The community trophic structure of Morgan's Creek, Meade County, Kentucky was analyzed through regular measurement of standing crops of the chief potential sources of plant materials available to the animals (suspended particulate, attached particulate, and allochthonous leaf materials) and an examination of their gut contents. The most important food was allochthonous leaf materials, which occurr ...
DOI:
10.2307/1933425

18. Seals and Group Selection

Author:
McLaren, Ian A.
Source:
Ecology 1967 v.48 no.1 pp. 104-110
ISSN:
0012-9658
Subject:
breeding sites; crushing; females; neonates; polygyny; seals; sexual selection
Abstract:
... Seals have been shown to restrict recruitment in crowded populations because of gregarious and hierarchical behavior. Some authors have suggested that such behavior has evolved through group selection to prevent overutilization of resources. Published data are reviewed to show that more highly social seals have higher potential rates of increase. This is difficult to reconcile with group selection ...
DOI:
10.2307/1933422

19. Seed Populations in Some Natural Australian Topsoils

Author:
Barbour, M. G.; Lange, R. T.
Source:
Ecology 1967 v.48 no.1 pp. 153-155
ISSN:
0012-9658
Subject:
microscopy; organic matter; seeds; soil sampling; vegetation types
Abstract:
... The numbers and types of seeds in topsoils of several South Australian vegetation types were tabulated by microscopic examination of soil samples. Isolation of organic matter by flotation on a dense solution followed by examination under 8x power gave excellent recovery of all seeds present, even of those as small as 1 mm. Relatively small sample volumes (50 cm³) appear sufficient to yield high fr ...
DOI:
10.2307/1933427

20. Studies of Subtidal Marine Vegetation in Western Washington

Author:
Neushul, M.
Source:
Ecology 1967 v.48 no.1 pp. 83-94
ISSN:
0012-9658
Subject:
Agarum; Callophyllis; Laminaria; Rhodoptilum; algae; benthic plants; community structure; environmental factors; vegetation; Puget Sound; Washington (state)
Abstract:
... Objectively defined, benthic plant associations in the Puget Sound region are compared with associations recorded by other workers, in this and other areas. A shallow Laminaria association, an Agarum dominated region at mid—depths and a red algal association of Rhodoptilum, Callophyllis, and hydroids near the lower (17 to 20 m) limits of plant distribution, are described. Variation in community co ...
DOI:
10.2307/1933420