Forty-one years of population change and community succession in aspen forests on four soil types, northern lower Michigan, U.S.A.

1985 ◽  
Vol 63 (9) ◽  
pp. 1641-1651 ◽  
Author(s):  
Mark R. Roberts ◽  
Curtis J. Richardson
Keyword(s):  
Population Dynamics ◽  
Seedling Establishment ◽  
Population Change ◽  
Acer Rubrum ◽  
Pinus Resinosa ◽  
Fagus Grandifolia ◽  
Soil Types ◽  
Community Succession ◽  
Vegetation Types ◽  
Stages Of Development

In 1938, four permanent 0.04-ha (0.1-acre) plots were established in pioneer aspen (Populus grandidentata Michx. and P. tremuloides Michx.) forests on dry-mesic to wet-mesic soils in Michigan. These sites are representative of the soils and vegetation types found in the region. Patterns of survival, growth, and recruitment of individual woody stems are determined from remeasurements in 1945, 1951, 1955, 1968, 1973, and 1979. Five patterns of change in species populations are identified, reflecting differences in reproductive characteristics and physiological requirements of the species: (1) early dominance, (2) delayed dominance, (3) persistence, (4) progressive recruitment, and (5) late recruitment. Patterns 1, 3, and 4 predominated on dry-mesic soils, reflecting slow replacement of aspen by Pinus resinosa Ait. and P. strobus L. from seedling origin, whereas all five patterns occurred on the mesic soil where Acer rubrum L., A. saccharum Marsh., and Fagus grandifolia Ehrh. increased in importance through both vegetative sprouting and seedling establishment. Recruitment on the dry-mesic soils did not correspond to the stages of development of the aspen overstory as determined from −3/2 thinning curves. In contrast, recruitment and growth in the understory appeared to be dependent upon the occurrence of canopy openings on the mesic soil. Species populations responded to insect defoliation on the wet-mesic plot, illustrating the importance of understanding population dynamics in studies of succession.

Vegetation variation among mesic successional forest stands in northern lower Michigan

1988 ◽  
Vol 66 (6) ◽  
pp. 1080-1090 ◽  
Author(s):  
Mark R. Roberts ◽  
Norman L. Christensen
Keyword(s):  
Quercus Rubra ◽  
Abies Balsamea ◽  
Acer Rubrum ◽  
Pinus Strobus ◽  
Pinus Resinosa ◽  
Fagus Grandifolia ◽  
Prunus Serotina ◽  
Stand Age ◽  
Site Conditions ◽  
Soil Variables

Vegetation composition of the shrub–tree and herb layers was sampled in 70 successional aspen (Populus tremuloides and Populus grandidentata) stands of different ages (1–90 years) on a variety of sites in northern lower Michigan. Physical and chemical characteristics of soil profiles were also measured at each site. Three stand groupings were identified based on site conditions and detrended correspondence analysis (DCA) ordination of the vegetation. Sandy dry-mesic soils support forests of Acer rubrum, Quercus rubra, Pinus resinosa, and Pinus strobus. On lowland sandy soils with a fluctuating water table, Pinus strobus, Abies balsamea, Viburnum lentago, and Viburnum cassinoides are important. Mesic soils with stratified calcareous layers or clay till substrates support Acer saccharum, Fagus grandifolia, Tilia americana, Fraxinus americana, Ostrya virginiana, and Acer pensylvanicum. Canonical correlation analysis (CCA) was used to compare DCA scores with soil variables; first-axis DCA scores were correlated with a suite of soil variables and stand age was correlated with second or third DCA axis scores. Separate DCA ordinations of the dry-mesic and mesic groups revealed successional relations on these sites. On dry-mesic sites, Pinus resinosa and Pinus strobus increase in importance with stand age, while Prunus serotina, Prunus virginiana, Prunus pensylvanica, and the aspens decrease. On mesic sites, early successional species include the aspens, Corylus cornuta, Prunus serotina, and Prunus pensylvanica. Fagus grandifolia, Acer pensylvanicum, Quercus rubra, Viburnum acerifolium, Betula papyrifera, Acer rubrum, and Tilia americana are more abundant in mature mesic-site stands. Ordinations of the herb data were remarkably similar to those for trees and shrubs except on dry-mesic sites. Much of the residual variability in vegetation not accounted for by site conditions and stand age is probably related to historical factors such as the nature of disturbance and variations in seed rain.

Status of Food Security in Banten Province, Indonesia

2019 ◽  
Author(s):  
Weksi Budiaji
Keyword(s):  
Population Dynamics ◽  
Food Security ◽  
Arable Land ◽  
Secondary Data ◽  
Disaster Risk ◽  
Soil Types ◽  
Indicator Variables ◽  
Cereal Production ◽  
The Status ◽  
Vast Area

This paper discusses the status of food security in Banten Province, Indonesia based on regional and city characteristics. Secondary data is used and is analyzed descriptively covering population dynamics, the population living in poverty, cereal production, disaster risk and soil types. Tangerang Region is found to have the largest population with the greatest number of people living in poverty among the regions and cities in Banten Province. Cereal production is dominated by the regions rather than the cities due to their vast area. Regarding arable land, flooding is the most threatening disaster in the major rice producing areas. In order to identify the distributions of regions and cities regarding food security, three indicator variables of food security dimensions are plotted, namely, cereal normative consumption, proportion of the population living in poverty, and proportion of malnourished babies. The three regions of Pandeglang Region, Lebak Region and Serang Region are grouped together in a less secure group.

scholarly journals Increasing frequency of low summer precipitation synchronizes dynamics and compromises metapopulation stability in the Glanville fritillary butterfly

2015 ◽  
Vol 282 (1806) ◽  
pp. 20150173 ◽  
Author(s):  
Ayco J. M. Tack ◽  
Tommi Mononen ◽  
Ilkka Hanski
Keyword(s):  
Population Dynamics ◽  
Population Change ◽  
Temporal Dynamics ◽  
Summer Precipitation ◽  
Life History Stage ◽  
General Effect ◽  
Spatial Synchrony ◽  
Glanville Fritillary Butterfly ◽  
Spatio Temporal

Climate change is known to shift species' geographical ranges, phenologies and abundances, but less is known about other population dynamic consequences. Here, we analyse spatio-temporal dynamics of the Glanville fritillary butterfly ( Melitaea cinxia ) in a network of 4000 dry meadows during 21 years. The results demonstrate two strong, related patterns: the amplitude of year-to-year fluctuations in the size of the metapopulation as a whole has increased, though there is no long-term trend in average abundance; and there is a highly significant increase in the level of spatial synchrony in population dynamics. The increased synchrony cannot be explained by increasing within-year spatial correlation in precipitation, the key environmental driver of population change, or in per capita growth rate. On the other hand, the frequency of drought during a critical life-history stage (early larval instars) has increased over the years, which is sufficient to explain the increasing amplitude and the expanding spatial synchrony in metapopulation dynamics. Increased spatial synchrony has the general effect of reducing long-term metapopulation viability even if there is no change in average metapopulation size. This study demonstrates how temporal changes in weather conditions can lead to striking changes in spatio-temporal population dynamics.

Influence of genotype and soil on root fan structures of Acer rubrum

1970 ◽  
Vol 48 (1) ◽  
pp. 147-152
Author(s):  
Richard J. Medve
Keyword(s):  
Plant Communities ◽  
Acer Rubrum ◽  
Soil Types ◽  
Red Maple ◽  
Root Characteristics ◽  
Third Order ◽  
Soil Sterilization ◽  
Seed Sources ◽  
Order Root

Soils collected from eight different plant communities that contained red maples (Acer rubrum L.) had little effect on root fan structures of red maple seedlings. Seedlings from eight seed sources, grown in the same soil types, showed a significant amount of variation for third order root characteristics. Root fan structures, especially those characteristics relating to beaded rootlets, were significantly affected by soil sterilization. Root fan structures were more copious and developed more rapidly on indigenous seedlings than on seedlings grown under greenhouse conditions.

scholarly journals Quantifying the effect of genetic, environmental and individual demographic stochastic variability for population dynamics in Plantago lanceolata

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ulrich K. Steiner ◽  
Shripad Tuljapurkar ◽  
Deborah A. Roach
Keyword(s):  
Population Dynamics ◽  
Population Growth ◽  
Population Change ◽  
Adaptive Dynamics ◽  
Plantago Lanceolata ◽  
Environmental Parameters ◽  
Experimental Population ◽  
Stochastic Variation ◽  
Survival And Reproduction ◽  
Stochastic Events

AbstractSimple demographic events, the survival and reproduction of individuals, drive population dynamics. These demographic events are influenced by genetic and environmental parameters, and are the focus of many evolutionary and ecological investigations that aim to predict and understand population change. However, such a focus often neglects the stochastic events that individuals experience throughout their lives. These stochastic events also influence survival and reproduction and thereby evolutionary and ecological dynamics. Here, we illustrate the influence of such non-selective demographic variability on population dynamics using population projection models of an experimental population of Plantago lanceolata. Our analysis shows that the variability in survival and reproduction among individuals is largely due to demographic stochastic variation with only modest effects of differences in environment, genes, and their interaction. Common expectations of population growth, based on expected lifetime reproduction and generation time, can be misleading when demographic stochastic variation is large. Large demographic stochastic variation exhibited within genotypes can lower population growth and slow evolutionary adaptive dynamics. Our results accompany recent investigations that call for more focus on stochastic variation in fitness components, such as survival, reproduction, and functional traits, rather than dismissal of this variation as uninformative noise.

Population Dynamics of Municipalities in Central Russia

2017 ◽  
Vol 2017 (6) ◽  
pp. 97-124
Author(s):  
Irina Kalabikhina ◽  
Denis Mokrensky
Keyword(s):  
Population Dynamics ◽  
Elderly Population ◽  
Population Change ◽  
Population Decline ◽  
The Elderly ◽  
Second Stage ◽  
Central Russia ◽  
Population Concentration ◽  
Population Reduction ◽  
Demographic Policy

In this paper we present the results of the analysis of the population change in nonmetropolitan city municipalities by components and concentration of population in the municipalities were investigated, their typologization was developed in accordance with the contribution of various components to population dynamics. The article discusses the limitations of municipal statistics. The methods of average values, the balance equation, and the measures of population concentration are used. The main conclusions confirm the trends of population decline at the second stage of demographic policy, territorial unevenness and concentration of population in administrative centers and the closest settlements to them. Less than 2% of the municipalities in question demonstrate both natural and migratory growth, and in 70% of municipalities both migration and natural components make a contribution to population reduction. The relatively high proportion of the elderly population was observed in the studied municipalities; crude birth and death rates were worse than the average in the district.

The role of seed reproduction in the dynamics of established populations of Hieracium floribundum and a comparison with that of vegetative reproduction

1975 ◽  
Vol 53 (24) ◽  
pp. 3022-3031 ◽  
Author(s):  
A. G. Thomas ◽  
H. M. Dale
Keyword(s):  
Population Dynamics ◽  
Seedling Establishment ◽  
Vegetative Reproduction ◽  
Soil Surface ◽  
Growing Season ◽  
Population Based ◽  
Early Spring ◽  
Viable Seed ◽  
Density Patch

In the crowded parts of patches of Hieracium floribundum Wimm. and Grab., which were established for at least a decade in an ungrazed pasture, 7–10% of the population (3700 individuals/m2) flowered. Of the plants that flowered, 94% were alive a year later, but only 5% of these flowered. Abortion of flower heads was common; one half of all those which were initiated in early June had aborted by flowering time in early July. Freshly dispersed seed had a viability of 57%, which was reduced to 17% a year later, after its storage close to the soil surface. Less than 6% of the viable seed was innately dormant. Dry, laboratory-stored seed retained its viability for the year but was slower to germinate than soil-stored seed. In field conditions, germination was temperature inhibited during most of the growing season. Maximum daytime microsite temperatures of less than 32 °C, which is necessary for germination, were found to occur only in early spring and late fall. Successful seedling establishment accounts for 1% of the individuals in a crowded population. Based on the maximum sexual reproduction from plants in crowded populations, a seed has a probability of 1 in 20 000 of becoming an established seedling. A model of population dynamics in a high-density patch traces the fate of seedling establishment, surviving adults, and stolon-derived rosettes for a single year.

Physical and historical determinants of the pre- and post-settlement forests of northwestern Pennsylvania

2003 ◽  
Vol 33 (9) ◽  
pp. 1683-1697 ◽  
Author(s):  
Gordon G Whitney ◽  
Joseph P DeCant
Keyword(s):  
19Th Century ◽  
Acer Saccharum ◽  
Petroleum Industry ◽  
Acer Rubrum ◽  
Fagus Grandifolia ◽  
Quercus Alba ◽  
Old Field ◽  
European Settlement ◽  
Northern Portion ◽  
The 19Th Century

Our analysis of the early land survey records and more recent U.S. Forest Service inventory data documents the changing nature of northwestern Pennsylvania's forests following European settlement. Initially, the northern portion of the four-county study area was dominated by forests of Fagus grandifolia Ehrh. and Acer saccharum Marsh. associated with the richer, finer-textured soils of the rolling Glaciated Appalachian Plateau. Up to 80% of the region was cleared for farming in the 19th century. Marginal farmland was abandoned and reverted to forests in the 20th century. Fires and leached, nutrient-poor soils favored the dominance of Quercus spp. and Castanea dentata (Marsh.) Borkh. in the presettlement forests of the rugged Unglaciated Appalachian Plateaus to the south. The rough nature of the terrain discouraged the early clearance of the plateaus' forests. The advent of the petroleum industry and its insatiable demand for barrels in the 19th century, however, assured the selective removal of the larger (>20 in. (50 cm) DBH) Quercus alba L. from the region's woods. The increasing homogeneity of northwestern Pennsylvania's forests today is due to the sharp decline of the more distinctive indicator species and the rise of a number of opportunistic old-field or gap species, notably Prunus serotina Ehrh. and Acer rubrum L.

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