scholarly journals A demographic approach to understanding the effects of climate on population growth

2019 ◽  
Author(s):  
Nicholas M. Caruso ◽  
Christina L. Staudhammer ◽  
Leslie J. Rissler
Keyword(s):  
Population Growth ◽  
Life History Traits ◽  
Experimental Studies ◽  
Elevational Gradient ◽  
Early Spring ◽  
Vital Rates ◽  
Active Season ◽  
Temperature And Precipitation ◽  
Early Fall ◽  
Survival And Growth

AbstractAmphibian life history traits are affected by temperature and precipitation. Yet, connecting these relationships to population growth, especially for multiple populations within a species, is lacking and precludes our understanding of how amphibians are distributed. Therefore, we constructed Integral Projection Models (IPM) for five populations along an elevational gradient to determine how climate and season affects population growth of a terrestrial salamander Plethodon montanus and the importance of demographic vital rates to population growth under varying climate scenarios. We found that population growth was typically higher at the highest elevation compared to the lower elevations whereas varying inactive season conditions, represented by the late fall, winter and early spring, produced a greater variation in population growth than varying active season conditions (late spring, summer, and early fall). Furthermore, survival and growth was consistently more important, as measured by elasticity, compared to fecundity and large females had the greatest elasticity compared to all other sizes. Our results suggest that changing inactive season conditions, especially those that would affect the survival of large individuals, may have the greatest impact on population growth. Therefore, we recommend experimental studies focused on the inactive season to determine the mechanism by which these conditions can affect survival.

scholarly journals Demographic consequences of climate variation along an elevational gradient for a montane terrestrial salamander

2017 ◽  
Author(s):  
Nicholas M. Caruso ◽  
Leslie J. Rissler
Keyword(s):  
Survival Rates ◽  
Elevational Gradient ◽  
Vital Rates ◽  
Life History Variation ◽  
Growth And Survival ◽  
Active Season ◽  
Asymptotic Size ◽  
Capture Recapture ◽  
Survival And Growth ◽  
The Relationship

AbstractClimate change represents a significant threat to amphibians, which are already imperiled. However, for many species, the relationship between demographic vital rates (survival and growth) and climate is unknown, which limits predictive models. Here we describe the life history variation ofPlethodon montanususing capture-recapture data over a period of four years, at five sites along an elevational gradient to determine how survival and growth vary with temperature, precipitation, and how these relationships vary with elevation. We used a hierarchical model to estimate asymptotic size and growth rate, and used a spatial Cormack-Jolly-Seber model to estimate probability of capture and survival, as well as dispersal variance. Our results show that during the active season, growth and survival rates are both positively affected by precipitation, while survival was positively affected by temperature at all elevations, the relationship between growth rates and temperature varied along the elevational gradient. Generally at lower elevations, higher temperatures led to a decrease in growth while at higher elevations the opposite was true. During the inactive season we found elevational variation in the relationship between survival and the amount of snow; at low elevations snowfall was low but survival decreased with increasing snowfall while at higher elevations increasing snowfall lead to higher survival. Our results demonstrate that understanding how the environment can affect salamander demography to develop mechanistic models, will require knowledge of the actual environmental conditions experienced by a given population as well as an understanding of the overall differences in climate at a given site.

scholarly journals Impact of climate extremes on wildlife plant flowering over Germany

2015 ◽  
Vol 12 (22) ◽  
pp. 18389-18423 ◽  
Author(s):  
J. F. Siegmund ◽  
M. Wiedermann ◽  
J. F. Donges ◽  
R. V. Donner
Keyword(s):  
Experimental Studies ◽  
Climate Extremes ◽  
Systematic Investigation ◽  
Early Spring ◽  
Statistical Tool ◽  
Temperature And Precipitation ◽  
The Earth ◽  
Spring Temperatures ◽  
The Impact

Abstract. Ongoing climate change is known to cause an increase in the frequency and amplitude of local temperature and precipitation extremes in many regions of the Earth. While gradual changes in the climatological conditions are known to strongly influence plant flowering dates, the question arises if and how extremes specifically impact the timing of this important phenological phase. In this study, we systematically quantify simultaneities between meteorological extremes and the timing of flowering of four shrub species across Germany by means of event coincidence analysis, a novel statistical tool that allows assessing whether or not two types of events exhibit similar sequences of occurrences. Our systematic investigation supports previous findings of experimental studies by highlighting the impact of early spring temperatures on the flowering of wildlife plants. In addition, we find statistically significant indications for some long-term relations reaching back to the previous year.

scholarly journals Impact of temperature and precipitation extremes on the flowering dates of four German wildlife shrub species

2016 ◽  
Vol 13 (19) ◽  
pp. 5541-5555 ◽  
Author(s):  
Jonatan F. Siegmund ◽  
Marc Wiedermann ◽  
Jonathan F. Donges ◽  
Reik V. Donner
Keyword(s):  
Experimental Studies ◽  
Early Spring ◽  
Precipitation Extremes ◽  
Shrub Species ◽  
Statistical Tool ◽  
Event Time ◽  
Temperature And Precipitation ◽  
Spring Temperatures ◽  
Cold Spring ◽  
The Impact

Abstract. Ongoing climate change is known to cause an increase in the frequency and amplitude of local temperature and precipitation extremes in many regions of the Earth. While gradual changes in the climatological conditions have already been shown to strongly influence plant flowering dates, the question arises if and how extremes specifically impact the timing of this important phenological phase. Studying this question calls for the application of statistical methods that are tailored to the specific properties of event time series. Here, we employ event coincidence analysis, a novel statistical tool that allows assessing whether or not two types of events exhibit similar sequences of occurrences in order to systematically quantify simultaneities between meteorological extremes and the timing of the flowering of four shrub species across Germany. Our study confirms previous findings of experimental studies by highlighting the impact of early spring temperatures on the flowering of the investigated plants. However, previous studies solely based on correlation analysis do not allow deriving explicit estimates of the strength of such interdependencies without further assumptions, a gap that is closed by our analysis. In addition to direct impacts of extremely warm and cold spring temperatures, our analysis reveals statistically significant indications of an influence of temperature extremes in the autumn preceding the flowering.

Performance of Indigenous, Exotic, and Hybrid Strains of Brook Trout (Salvelinus fontinalis) in Waters of the Adirondack Mountains, New York

1981 ◽  
Vol 38 (12) ◽  
pp. 1701-1707 ◽  
Author(s):  
Dwight A. Webster ◽  
William A. Flick
Keyword(s):  
New York ◽  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Hybrid Vigor ◽  
Superior Performance ◽  
Adirondack Mountains ◽  
Wild Strains ◽  
Early Fall ◽  
Survival And Growth ◽  
Wild Trout

Eleven year-classes of wild, domestic, and wild × domestic hybrid strains of brook trout (Salvelinus fontinalis) were stocked in a 0.19-ha Adirondack pond. Comparative survival and growth were assessed upon drainage in early fall. Rearing native wild strains to maturity in a hatchery, or domestic strains in a natural environment, did not consistently or materially affect survival of progeny, suggesting that superior performance of wild strains was largely inherent. Interstrain hybrids of wild × domestic showed survivals equivalent to the wild parents, but hybrids of two Canadian strains gave evidence of heterosis in both survival and net yield. Supplementary observations in other waters also indicated that one strain (Assinica) may be less adaptable to Adirondack conditions than the other (Temiscamie).Key words: brook trout, wild trout, domesticated trout, interstrain hybrid trout, survival, growth, heterosis, hybrid vigor

Fall and Spring Preplant Herbicide Applications Influence Spring Emergence of Glyphosate-Resistant Horseweed (Conyza canadensis)

2010 ◽  
Vol 24 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Vince M. Davis ◽  
Greg R. Kruger ◽  
Bryan G. Young ◽  
William G. Johnson
Keyword(s):  
Early Spring ◽  
Late Spring ◽  
Conyza Canadensis ◽  
No Till ◽  
Early Fall ◽  
Winter Annual ◽  
Winter Annual Weeds ◽  
Annual Weeds ◽  
Spring Emergence ◽  
Residual Control

Horseweed (Conyza canadensis) is a common weed in no-till crop production systems. It is problematic because of the frequent occurrence of biotypes resistant to glyphosate and acetolactate synthase (ALS)-inhibiting herbicides and its ability to complete its life cycle as a winter or summer annual weed. Tactics to control horseweed while controlling other winter annual weeds routinely fail; herbicide application timing and spring emergence patterns of horseweed may be responsible. The objectives of this experiment were to (1) determine the influence of fall and spring herbicides with and without soil residual horseweed activity on spring-emerging glyphosate-resistant (GR) horseweed density and (2) evaluate the efficacy and persistence of saflufenacil on GR horseweed. Field studies were conducted in southern Indiana and Illinois from fall 2006 to summer 2007 and repeated in 2007 to 2008. Six preplant herbicide treatments were applied at four application timings: early fall, late fall, early spring, and late spring. Horseweed plants were counted every 2 wk following the first spring application until the first week of July. Horseweed almost exclusively emerged in the spring at both locations. Spring horseweed emergence was higher when 2,4-D + glyphosate was fall-applied and controlled other winter annual weeds. With fall-applied 2,4-D + glyphosate, over 90% of the peak horseweed density was observed before April 25. In contrast, only 25% of the peak horseweed density was observed in the untreated check by April 25. Starting from the initiation of horseweed emergence in late March, chlorimuron + tribenuron applied early fall or early spring, and spring-applied saflufenacil at 100 g ai/ha provided greater than 90% horseweed control for 12 wk. Early spring–applied saflufenacil at 50 g ai/ha provided 8 wk of greater than 90% residual control, and early spring–applied simazine provided 6 wk of greater than 90% control. When applied in late spring, saflufenacil was the only herbicide treatment that reduced horseweed densities by greater than 90% compared to 2,4-D + glyphosate. We concluded from this research that fall applications of nonresidual herbicides can increase the rate and density of spring emerging horseweed. In addition, spring-applied saflufenacil provides no-till producers with a new preplant herbicide for foliar and residual control of glyphosate- and ALS-resistant horseweed.

scholarly journals Beyond demographic buffering: Context dependence in demographic strategies across animals

2021 ◽  
Author(s):  
Omar Lenzi ◽  
Arpat Ozgul ◽  
Roberto Salguero-Gomez ◽  
Maria Paniw
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Temporal Variation ◽  
Population Growth Rate ◽  
Natural Populations ◽  
Environmental Context ◽  
Context Dependence ◽  
Vital Rate ◽  
Rate Variation ◽  
Vital Rates

Temporal variation in vital rates (e.g., survival, reproduction) can decrease the long-term mean performance of a population. Species are therefore expected to evolve demographic strategies that counteract the negative effects of vital rate variation on the population growth rate. One key strategy, demographic buffering, is reflected in a low temporal variation in vital rates critical to population dynamics. However, comparative studies in plants have found little evidence for demographic buffering, and little is known about the prevalence of buffering in animal populations. Here, we used vital rate estimates from 31 natural populations of 29 animal species to assess the prevalence of demographic buffering. We modeled the degree of demographic buffering using a standard measure of correlation between the standard deviation of vital rates and the sensitivity of the population growth rate to changes in such vital rates across populations. We also accounted for the effects of life-history traits, i.e., age at first reproduction and spread of reproduction across the life cycle, on these correlation measures. We found no strong or consistent evidence of demographic buffering across the study populations. Instead, key vital rates could vary substantially depending on the specific environmental context populations experience. We suggest that it is time to look beyond concepts of demographic buffering when studying natural populations towards a stronger focus on the environmental context-dependence of vital-rate variation.

Life history and environmental influences on population dynamics in sockeye salmon

2014 ◽  
Vol 71 (8) ◽  
pp. 1198-1208 ◽  
Author(s):  
Douglas C. Braun ◽  
John D. Reynolds
Keyword(s):  
Population Dynamics ◽  
Life History ◽  
Population Growth ◽  
Growth Rates ◽  
Environmental Conditions ◽  
Sockeye Salmon ◽  
Life History Traits ◽  
Relative Importance ◽  
Population Growth Rates ◽  
Habitat Variables

Understanding linkages among life history traits, the environment, and population dynamics is a central goal in ecology. We compared 15 populations of sockeye salmon (Oncorhynchus nerka) to test general hypotheses for the relative importance of life history traits and environmental conditions in explaining variation in population dynamics. We used life history traits and habitat variables as covariates in mixed-effect Ricker models to evaluate the support for correlates of maximum population growth rates, density dependence, and variability in dynamics among populations. We found dramatic differences in the dynamics of populations that spawn in a small geographical area. These differences among populations were related to variation in habitats but not life history traits. Populations that spawned in deep water had higher and less variable population growth rates, and populations inhabiting streams with larger gravels experienced stronger negative density dependence. These results demonstrate, in these populations, the relative importance of environmental conditions and life histories in explaining population dynamics, which is rarely possible for multiple populations of the same species. Furthermore, they suggest that local habitat variables are important for the assessment of population status, especially when multiple populations with different dynamics are managed as aggregates.

scholarly journals Weed seed bank emergence across the Corn Belt

Weed Science ◽  
1997 ◽  
Vol 45 (1) ◽  
pp. 67-76 ◽  
Author(s):  
Frank Forcella ◽  
Robert G. Wilson ◽  
Jack Dekker ◽  
Robert J. Kremer ◽  
John Cardina ◽  
...  
Keyword(s):  
Soil Temperature ◽  
Field Experiments ◽  
Soil Depth ◽  
Early Spring ◽  
Temperature And Precipitation ◽  
Secondary Dormancy ◽  
Giant Foxtail ◽  
Green Foxtail ◽  
Viable Seeds ◽  
Common Purslane

Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartweed, 25.1 (65); common purslane, 15.4 (135); common ragweed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigweed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotweed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June.

Sign in / Sign up

Export Citation Format

Share Document