Jump to Main Content
PubAg
Main content area
Search
« Previous |
1 - 20 of 25
|
Next »
Search Results
- Author:
- MacDougall, Andrew S.; Turkington, Roy
- Source:
- Ecology 2005 v.86 no.1 pp. 42-55
- ISSN:
- 0012-9658
- Subject:
- Poa pratensis; grasses; ecological succession; Dactylis glomerata; environmental degradation; savannas; plant competition; invasive species; British Columbia
- Abstract:
- ... Few invaded ecosystems are free from habitat loss and disturbance, leading to uncertainty whether dominant invasive species are driving community change or are passengers along for the environmental ride. The “driver” model predicts that invaded communities are highly interactive, with subordinate native species being limited or excluded by competition from the exotic dominants. The “passenger” mo ...
- DOI:
- 10.1890/04-0669
-
http://dx.doi.org/10.1890/04-0669
- Author:
- Valett, H. M.; Baker, M. A.; Morrice, J. A.; Crawford, C. S.; Molles, M. C., Jr.; Dahm, C. N.; Moyer, D. L.; Thibault, J. R.; Ellis, Lisa M.
- Source:
- Ecology 2005 v.86 no.1 pp. 220-234
- ISSN:
- 0012-9658
- Subject:
- rivers; water analysis; riparian forests; semiarid zones; soil nutrient dynamics; floodplains; forest ecosystems; forest soils; soil respiration; New Mexico
- Abstract:
- ... Flood pulse inundation of riparian forests alters rates of nutrient retention and organic matter processing in the aquatic ecosystems formed in the forest interior. Along the Middle Rio Grande (New Mexico, USA), impoundment and levee construction have created riparian forests that differ in their inter‐flood intervals (IFIs) because some floodplains are still regularly inundated by the flood pulse ...
- DOI:
- 10.1890/03-4091
-
http://dx.doi.org/10.1890/03-4091
- Author:
- Lawrence, Deborah
- Source:
- Ecology 2005 v.86 no.1 pp. 26-33
- ISSN:
- 0012-9658
- Subject:
- secondary forests; tropical rain forests; shifting cultivation; deforestation; dry matter accumulation; fallow; history; life history; plant density; soil fertility; carbon sequestration; Indonesia; Borneo
- Abstract:
- ... I examined the effect of repeated long‐fallow shifting cultivation on biomass accumulation in a rain‐forest landscape occupied for over 200 years in West Kalimantan, Indonesia. The diameters of stems >5 cm dbh were measured in nine secondary forests using a stratified random design of nested plots (3000 m² per site). The stands were 9–12 years old and had experienced from 1 to 10 or more cycles of ...
- DOI:
- 10.1890/03-0564
-
http://dx.doi.org/10.1890/03-0564
- Author:
- Snäll, Tord; Ehrlén, Johan; Rydin, Håkan
- Source:
- Ecology 2005 v.86 no.1 pp. 106-115
- ISSN:
- 0012-9658
- Subject:
- mosses and liverworts; colonizing ability; extinction; population dynamics; host plants; forest trees; population size; simulation models; Sweden
- Abstract:
- ... Metapopulation dynamics have received much attention in population biology and conservation. Most studies have dealt with species whose population turnover rate is much higher than the rate of patch turnover. Models of the dynamics in such systems have assumed a static patch landscape. The dynamics of many species, however, are likely to be significantly affected by the dynamics of their patches. ...
- DOI:
- 10.1890/04-0531
-
http://dx.doi.org/10.1890/04-0531
- Author:
- Viljugrein, Hildegunn; Stenseth, Nils Chr; Smith, Graham W.; Steinbakk, Gunnhildur H.
- Source:
- Ecology 2005 v.86 no.1 pp. 245-254
- ISSN:
- 0012-9658
- Subject:
- waterfowl; prairies; population dynamics; population density; population size; statistical models; breeding sites
- Abstract:
- ... Knowing whether, and to what extent, populations are regulated by density‐dependent factors is important both in its own right and when developing management strategies for wildlife species. However, available tests for density dependence are typically sensitive to sampling errors in the data. By using a state‐space modeling approach, incorporating both an ecological process model and an observati ...
- DOI:
- 10.1890/04-0467
-
http://dx.doi.org/10.1890/04-0467
- Author:
- Landis, R. Matthew; Peart, David R.
- Source:
- Ecology 2005 v.86 no.1 pp. 63-72
- ISSN:
- 0012-9658
- Subject:
- Abies balsamea; Betula cordifolia; Betula pubescens var. pumila; Picea rubens; canopy; forest trees; life history; models; population ecology; saplings; shade tolerance; subalpine forests; Northeastern United States
- Abstract:
- ... Few individuals in canopy tree species attain the canopy and reproduce. Understanding why these select few succeed is fundamental to tree population ecology and forest community dynamics. Yet our understanding remains poor, because the time required to reach the canopy is long relative to experimental and demographic studies. We used a simple, yet powerful, approach to examine the long‐term proces ...
- DOI:
- 10.1890/03-0848
-
http://dx.doi.org/10.1890/03-0848
- Author:
- Schindler, Daniel E.; Rogers, Donald E.; Scheuerell, Mark D.; Abrey, Caryn A.
- Source:
- Ecology 2005 v.86 no.1 pp. 198-209
- ISSN:
- 0012-9658
- Subject:
- climate change; ice; Oncorhynchus nerka; zooplankton; animal growth; population density; time series analysis; equations; Alaska
- Abstract:
- ... Detecting and forecasting the effects of changing climate on natural and exploited populations represent a major challenge to ecologists and resource managers. These efforts are complicated by underlying density‐dependent processes and the differential responses of predators and their prey to changing climate. We explored the effects of density‐dependence and changing climate on growth of juvenile ...
- DOI:
- 10.1890/03-0408
-
http://dx.doi.org/10.1890/03-0408
- Author:
- Craine, Joseph M.; Lee, William G.; Bond, William J.; Williams, Richard J.; Johnson, Loretta C.
- Source:
- Ecology 2005 v.86 no.1 pp. 12-19
- ISSN:
- 0012-9658
- Subject:
- grasses; nitrogen content; geographical variation; quantitative genetics; environmental factors; grasslands; roots; leaves; New Zealand; Australia; North America; South Africa
- Abstract:
- ... Uncertainties regarding the relationships between leaf and root traits have impeded an integrated understanding of plant evolution and the efficient parameterization of ecosystem models. We measured key root and leaf traits of grasses from 77 sites in four grassland regions of the world (New Zealand, Australia, South Africa, North America). Within each region, the relationships among leaf traits p ...
- DOI:
- 10.1890/04-1075
-
http://dx.doi.org/10.1890/04-1075
- Author:
- Genkai-Kato, Motomi; Carpenter, Stephen R.
- Source:
- Ecology 2005 v.86 no.1 pp. 210-219
- ISSN:
- 0012-9658
- Subject:
- limnology; lakes; eutrophication; phosphorus; pollution load; water management; macroalgae; mathematical models; equations
- Abstract:
- ... Lakes may have alternative states due to excessive phosphorus (P) input: a clear‐water state and turbid one with high chlorophyll concentrations. Because shifts between these states have large ecosystem effects, and restoration after the shifts is costly or sometimes impossible, precise evaluation of the possibility of alternative states is needed for lake management. Yet the shifts are quite vari ...
- DOI:
- 10.1890/03-0545
-
http://dx.doi.org/10.1890/03-0545
- Author:
- Dubois, Frédérique; Giraldeau, Luc-Alain
- Source:
- Ecology 2005 v.86 no.1 pp. 3-11
- ISSN:
- 0012-9658
- Subject:
- ecological competition; aggression; population size; population density; predation; evolutionarily stable strategy; mathematical models
- Abstract:
- ... The study of the ecological factors that govern fighting over resources has been analyzed by resource defense theory and evolutionary hawk–dove games. In essence, the models predict that increasing economic defendability of a resource should lead to increased frequency of aggression among competitors. We question this prediction because it is based on the assumption that individuals that do not po ...
- DOI:
- 10.1890/04-0566
-
http://dx.doi.org/10.1890/04-0566
- Author:
- De Block, Marjan; Stoks, Robby
- Source:
- Ecology 2005 v.86 no.1 pp. 185-197
- ISSN:
- 0012-9658
- Subject:
- Lestes; life history; developmental stages; insect development; environmental factors; eclosion; body size
- Abstract:
- ... Although complex life cycles are widespread, we know little about how constraints in the larval stage influence adult fitness. Most models assume a tight coupling of larval conditions and adult fitness through size and timing of the life history transition. However, there are few empirical tests of this assumption. We combined an experimental manipulation of larval environment with a subsequent st ...
- DOI:
- 10.1890/04-0116
-
http://dx.doi.org/10.1890/04-0116
- Author:
- Gardner, Toby A.; Côté, Isabelle M.; Gill, Jennifer A.; Grant, Alastair; Watkinson, Andrew R.
- Source:
- Ecology 2005 v.86 no.1 pp. 174-184
- ISSN:
- 0012-9658
- Subject:
- coral reefs; hurricanes
- Abstract:
- ... The decline of corals on tropical reefs is usually ascribed to a combination of natural and anthropogenic factors, but the relative importance of these causes remains unclear. In this paper, we attempt to quantify the contribution of hurricanes to Caribbean coral cover decline over the past two decades using meta‐analyses. Our study included published and unpublished data from 286 coral reef sites ...
- DOI:
- 10.1890/04-0141
-
http://dx.doi.org/10.1890/04-0141
- Author:
- Hille Ris Lambers, Janneke; Clark, James S.; Lavine, Michael
- Source:
- Ecology 2005 v.86 no.1 pp. 85-95
- ISSN:
- 0012-9658
- Subject:
- temperate forests; deciduous forests; forest trees; buried seeds; viability; seed productivity; seed dormancy; plant density; tree mortality; North Carolina; Appalachian region
- Abstract:
- ... Seed dormancy is assumed to be unimportant for population dynamics of temperate woody species, because seeds occur at low densities and are short lived in forest soils. However, low soil seed densities may result from low seed production, and even modest seed longevity can buffer against fluctuating seed production, potentially limiting density‐dependent mortality and ensuring that seeds are avail ...
- DOI:
- 10.1890/03-0685
-
http://dx.doi.org/10.1890/03-0685
- Author:
- Hoffmann, Michael D.; Dodson, Stanley I.
- Source:
- Ecology 2005 v.86 no.1 pp. 255-261
- ISSN:
- 0012-9658
- Subject:
- lakes; zooplankton; species diversity; mathematical models
- Abstract:
- ... Two major ecological generalizations are that species richness increases monotonically with habitat size and that it is often a unimodal function of primary productivity. We performed a meta‐analysis to test hypotheses that, in 41 well‐studied lakes of the world, these patterns are an artifact of combining data from pristine and developed lakes. The monotonic species–area relationship was found in ...
- DOI:
- 10.1890/03-0833
-
http://dx.doi.org/10.1890/03-0833
- Author:
- Perakis, Steven S.; Compton, Jana E.; Hedin, Lars O.
- Source:
- Ecology 2005 v.86 no.1 pp. 96-105
- ISSN:
- 0012-9658
- Subject:
- temperate forests; old-growth forests; forest soils; nitrogen fertilizers; soil nutrient balance; soil nutrient dynamics; nitrification; Chile
- Abstract:
- ... Accelerated nitrogen (N) inputs can drive nonlinear changes in N cycling, retention, and loss in forest ecosystems. Nitrogen processing in soils is critical to understanding these changes, since soils typically are the largest N sink in forests. To elucidate soil mechanisms that underlie shifts in N cycling across a wide gradient of N supply, we added ¹⁵NH₄ ¹⁵NO₃ at nine treatment levels ranging i ...
- DOI:
- 10.1890/04-0415
-
http://dx.doi.org/10.1890/04-0415
- Author:
- Sorensen, Jennifer S.; McLister, James D.; Dearing, M. Denise
- Source:
- Ecology 2005 v.86 no.1 pp. 140-154
- ISSN:
- 0012-9658
- Subject:
- food intake; energy metabolism; Juniperus; herbivores; secondary metabolites; energy balance; Larrea tridentata; animal physiology; rats; phenolic compounds
- Abstract:
- ... Theory predicts that dietary specialization is limited in part because of physiological trade‐offs associated with specialization. Specifically, dietary specialists are predicted to evolve mechanisms that reduce costs and enhance excretion of plant secondary metabolites (PSMs) that they frequently consume, but are less energetically and/or mechanistically efficient at eliminating novel PSMs. Altho ...
- DOI:
- 10.1890/03-0669
-
http://dx.doi.org/10.1890/03-0669
- Author:
- Sorensen, Jennifer S.; McLister, James D.; Dearing, M. Denise
- Source:
- Ecology 2005 v.86 no.1 pp. 125-139
- ISSN:
- 0012-9658
- Subject:
- food intake; energy metabolism; herbivores; secondary metabolites; energy balance; rats; digestible energy; excretion
- Abstract:
- ... Ingestion of plant secondary metabolites (PSMs) presents a physiological and behavioral challenge for mammalian herbivores. Herbivores must not only detoxify PSMs, but they may also deal with energetic constraints such as reduced food intake, mass loss, increased excretion of energy, and increased metabolic demands. We hypothesized that the energetic consequences of consuming PSMs will significant ...
- DOI:
- 10.1890/03-0627
-
http://dx.doi.org/10.1890/03-0627
- Author:
- Fagan, William F.; Aumann, Craig; Kennedy, Christina M.; Unmack, Peter J.
- Source:
- Ecology 2005 v.86 no.1 pp. 34-41
- ISSN:
- 0012-9658
- Subject:
- deserts; freshwater fish; extinction; risk assessment; habitat fragmentation; databases; Sonoran Desert
- Abstract:
- ... Attributes of a species' spatial distribution, such as the number of occurrences and the spatial distribution of those occurrences, can affect extinction risk. Extinction risk, however, is scale dependent, and it is unclear how scale dependency affects linkages between species' distributions and extinction risk. Here, we evaluate the relationships between number of occurrences, distributional frag ...
- DOI:
- 10.1890/04-0491
-
http://dx.doi.org/10.1890/04-0491
- Author:
- Richardson, Sarah J.; Peltzer, Duane A.; Allen, Robert B.; McGlone, Matt S.
- Source:
- Ecology 2005 v.86 no.1 pp. 20-25
- ISSN:
- 0012-9658
- Subject:
- chronosequences; conifers; forest trees; resorption; soil nutrients; nitrogen; nutrient availability; forest litter; soil fertility; tree ferns; Angiospermae; phosphorus; leaves; New Zealand
- Abstract:
- ... Soil nitrogen and phosphorus pools shift strongly along soil chronosequences worldwide, but variation in plant nutrient resorption along these sequences is poorly understood. We quantified leaf and litter nutrient concentrations in 28 woody species along the Franz Josef soil chronosequence, New Zealand, a strong fertility gradient in temperate rain forest, to address two questions: How do leaf and ...
- DOI:
- 10.1890/04-0524
-
http://dx.doi.org/10.1890/04-0524
- Author:
- Schulte-Hostedde, Albrecht I.; Zinner, Bertram; Millar, John S.; Hickling, Graham J.
- Source:
- Ecology 2005 v.86 no.1 pp. 155-163
- ISSN:
- 0012-9658
- Subject:
- small mammals; body condition; body size; regression analysis; body mass index; Alberta
- Abstract:
- ... Body condition can have important fitness consequences, but measuring body condition of live animals from wild populations has been the subject of much recent debate. Using the residuals from a regression of body mass on a linear measure of body size is one of the most common methods of measuring condition and has been used in many vertebrate taxa. Recently, the use of this method has been critici ...
- DOI:
- 10.1890/04-0232
-
http://dx.doi.org/10.1890/04-0232