scholarly journals Radial Growth Patterns Associated with Tree Mortality in Nothofagus pumilio Forest

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 489 ◽  
Author(s):  
Milagros Rodríguez-Catón ◽  
Ricardo Villalba ◽  
Ana Srur ◽  
A. Park Williams
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Forest Dynamics ◽  
Radial Growth ◽  
Tree Mortality ◽  
Growth Patterns ◽  
Severe Drought ◽  
Nothofagus Pumilio ◽  
Total Size ◽  
Growth Trends

Tree mortality is a key process in forest dynamics. Despite decades of effort to understand this process, many uncertainties remain. South American broadleaf species are particularly under-represented in global studies on mortality and forest dynamics. We sampled monospecific broadleaf Nothofagus pumilio forests in northern Patagonia to predict tree mortality based on stem growth. Live or dead conditions in N. pumilio trees can be predicted with high accuracy using growth rate as an explanatory variable in logistic models. In Paso Córdova (CO), Argentina, where the models were calibrated, the probability of death was a strong negative function of radial growth, particularly during the six years prior to death. In addition, negative growth trends during 30 to 45 years prior to death increased the accuracy of the models. The CO site was affected by an extreme drought during the summer 1978–1979, triggering negative trends in radial growth of many trees. Individuals showing below-average and persistent negative trends in radial growth are more likely to die than those showing high growth rates and positive growth trends in recent decades, indicating the key role of droughts in inducing mortality. The models calibrated at the CO site showed high verification skill by accurately predicting tree mortality at two independent sites 76 and 141 km away. Models based on relative growth rates showed the highest and most balanced accuracy for both live and dead individuals. Thus, the death of individuals across different N. pumilio sites was largely determined by the growth rate relative to the total size of the individuals. Our findings highlight episodic severe drought as a triggering mechanism for growth decline and eventual death for N. pumilio, similar to results found previously for several other species around the globe. In the coming decades, many forests globally will be exposed to more frequent and/or severe episodes of reduced warm-season soil moisture. Tree-ring studies such as this one can aid prediction of future changes in forest productivity, mortality, and composition.

scholarly journals A synthesis of radial growth patterns preceding tree mortality

2016 ◽  
Vol 23 (4) ◽  
pp. 1675-1690 ◽  
Author(s):  
Maxime Cailleret ◽  
Steven Jansen ◽  
Elisabeth M. R. Robert ◽  
Lucía Desoto ◽  
Tuomas Aakala ◽  
...  
Keyword(s):  
Radial Growth ◽  
Tree Mortality ◽  
Growth Patterns

Abstract 13513: Serial CT Surveillance of Abdominal Aortic Aneurysm Diameter Demonstrates Predominantly Linear Growth (N-TA 3 CT)

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Sydney Olson ◽  
Marniker Wijesinha ◽  
Annalise Panthofer ◽  
William Blackwelder ◽  
Gilbert R Upchurch ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Linear Growth ◽  
Growth Patterns ◽  
Aortic Aneurysms ◽  
Transverse Diameter ◽  
Invasive Treatment ◽  
Abdominal Aortic ◽  
Risk Of Rupture ◽  
Serial Ct

Objective: Small abdominal aortic aneurysms (AAAs) have a low risk of rupture. Intervention is indicated when diameters exceed established thresholds. This study assessed the growth rates and patterns of AAAs over 2 years as documented on serial CT scans from the Non-Invasive Treatment of AAA Clinical Trial. Methods: 254 patients, 35 females with baseline AAA maximum transverse diameter (MTD) between 3.5-4.5 cm and 219 males with baseline MTD 3.5-5.0 cm, were included in this study. Linear regressions and segmental growth rates were used to model growth rates and patterns. Results: The yearly growth rates of AAA MTDs had a median of 0.17 cm/yr and mean of 0.19 cm/yr ± 0.14 (Figure 1). 10% of AAA displayed minimal to no growth (< 0.05 cm/yr), 62% low growth (0.05-0.25 cm/yr), 28% high growth (> 0.25 cm/yr). Baseline AAA diameter accounted for only 5.4% of growth rate variance (P<0.001, R 2 0.05). Most AAAs displayed linear growth (70%); large variations in interval growth rates occurred infrequently (3% staccato growth, 4% exponential growth); a minority of subjects’ growth patterns were not clearly classifiable (11% indeterminate-not growing, 12% indeterminate-growing) (Figure 2). No patients with baseline MTD < 4.25 cm exceeded sex-specific repair thresholds (males 0 / 92, [95% CI, 0.00-0.06]; females 0 / 25 [95% CI, 0.00-0.25]) in the course of follow-up for as long as two years. Conclusions: The majority of small AAAs exhibit linear growth; large intra-patient growth rate variations were infrequently observed over 2 years. AAA < 4.25 cm can be followed with a CT scan in 2 years with little chance of exceeding interventional MTD thresholds of 5.5 cm for men.

In situ growth rate estimates of Southern Ocean krill, Thysanoessa macrura

2019 ◽  
Vol 31 (3) ◽  
pp. 116-122 ◽  
Author(s):  
Jake R. Wallis ◽  
Jessica E. Melvin ◽  
Robert King ◽  
So Kawaguchi
Keyword(s):  
Growth Rate ◽  
Southern Ocean ◽  
Growth Rates ◽  
Somatic Growth ◽  
Growth Patterns ◽  
Daily Growth ◽  
Thysanoessa Macrura ◽  
Growth Method ◽  
Repeated Sampling ◽  
The Antarctic

AbstractGrowth, which is intrinsically linked to environmental conditions including temperature and food availability are highly variable both temporally and spatially. Estimates of growth rates of the Southern Ocean euphausiid Thysanoessa macrura are currently restricted to limited studies which rely upon repeated sampling and length-frequency analysis to quantify growth rates. The instantaneous growth method (IGR) was used to measure the growth rate of T. macrura successfully in the southern Kerulen Plateau region during summer, providing the first IGR parameters for the Southern Ocean euphausiid species. Results of the four-day IGR incubation indicate a period of low somatic growth for adult T. macrura. Males had a longer intermoult period (IMP) (62 days) than females (42 days), but the sexes exhibited similar daily growth rates of 0.011 mm day−1 and 0.012 mm day−1 respectively. Juveniles exhibited the fastest growth, with an IMP of 13 days and daily growth rate of 0.055 mm day−1 indicating a prolonged growth season, similar to the Antarctic krill E. superba. Consequently, we highlight the usability of the IGR method and strongly encourage its use in developing a comprehensive understanding of spatial and seasonal growth patterns of T. macrura.

Ecological Traits of the Eucalyptus L'hérit Subgenera Monocalyptus and Symphyomyrtus

1989 ◽  
Vol 37 (3) ◽  
pp. 207 ◽  
Author(s):  
IR Noble
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Root Morphology ◽  
Related Species ◽  
Early Growth ◽  
Growth Patterns ◽  
Leaf Chemistry ◽  
Ecological Traits ◽  
Closely Related Species ◽  
Genus Eucalyptus

The genus Eucalyptus L'Hérit. dominates most of the forests and woodlands of Australia. Many stands consist of intimate mixtures of species from different subgenera. The ecological traits of the two largest subgenera, Symphyomyrtus and Monocalyptus, are reviewed. Consistent differences in herbivore and parasite damage to leaves; in water relations; in tolerance to waterlogging, flooding, salinity and frost; in nutrient usage; in response to Phytophthora cinnamorni; and in early growth patterns are described. These can be summarised as differences in leaf chemistry; in root morphology, chemistry and activity; and in early growth rates. It is suggested that the differences in the ecological traits, and especially in the early growth rate, may help explain the coexistence of closely related species of similar habits in eucalypt communities.

Growth ecology of the tree lizard Urosaurus bicarinatus (Squamata: Phrynosomatidae), in a tropical dry forest of the Chamela Region, Mexico

2016 ◽  
Vol 66 (2) ◽  
pp. 189-199 ◽  
Author(s):  
Aurelio Ramírez-Bautista ◽  
Uriel Hernández-Salinas ◽  
J. Gastón Zamora-Abrego
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Growth Rates ◽  
Average Rate ◽  
Growth Patterns ◽  
Dry Forest ◽  
Von Bertalanffy ◽  
Mexican Pacific ◽  
Males And Females ◽  
Tree Lizard

Determination of growth rate provides an important component of an organism’s life history, making estimations of size at maturity, survival rate, and longevity possible. Here, we report on growth rate of males and females of the tropical tree lizard Urosaurus bicarinatus, in a seasonal environment in the state of Jalisco on the Mexican Pacific Coast. We calculated body growth rates and fitted these to the Von Bertalanffy, the logistic-by-length, and the logistic-by-weight growth models. The Von Bertalanffy model provided the best fit, and we used it to analyze the growth pattern. Males and females did not differ in estimated asymptotic size and other characteristic growth parameters. Estimated growth curve predicted an age at maturity of 38 mm SVL on 120 days for males, and 40 mm SVL on 170 days for females. On the basis of the similarities in the growth rates between the sexes, comparisons were made between seasons, and we found that the average rate of growth was slightly, albeit insignificantly, higher in the rainy season than in the dry season. The similarities in the growth patterns for the sexes of this species might be indicative of variance in its life history traits (e.g., fecundity, egg size) compared to those of other populations of this species and other species of this genus; therefore, it is important to document interpopulation differences to understand the evolutionary changes that have led to optimal adaptation in a particular environment more accurately.

Contrasting radial growth and canopy recruitment patterns in Liriodendrontulipifera and Nyssasylvatica: gap-obligate versus gap-facultative tree species

1994 ◽  
Vol 24 (11) ◽  
pp. 2141-2149 ◽  
Author(s):  
David A. Orwig ◽  
Marc D. Abrams
Keyword(s):  
Tree Species ◽  
Forest Dynamics ◽  
Radial Growth ◽  
Life Histories ◽  
Ring Width ◽  
Canopy Gaps ◽  
Growth Patterns ◽  
Growth Strategies ◽  
Shade Tolerant Species ◽  
Quercus Forests

Radial growth patterns, canopy recruitment characteristics, and disturbance histories were examined in a shade-tolerant species, Nyssasylvatica Marsh., and a shade-intolerant species, Liriodendrontulipifera L., to determine the influence of canopy gaps in species with contrasting life histories. Tree cores of these co-occurring species were taken from three mixed-Quercus forests in northern Virginia. Most N. sylvatica individuals became established prior to 1850 and experienced multiple release and suppression periods coinciding with logging during the late 1800s and early 1900s. Many L. tulipifera became established during the early 1900s following logging, and only a few individuals experienced prolonged suppression periods. Regardless of site, L. tulipifera grew faster than N. sylvatica (average radial growth >1.70 mm/year for L. tulipifera vs. <0.82 mm/year for N. sylvatica.). Liriodendrontulipifera also exhibited longer periods of mean yearly growth >2 mm (15–37 years for L. tulipifera vs. <5 years for Nsylvatica). Consecutive growth <0.5 mm/year ranged from 43 to 66 years in N. sylvatica vs. 2–11 years in L. tulipifera. Ring width patterns indicate that both species used different strategies following disturbance that enabled them to coexist in these forests. Nyssasylvatica persisted in subcanopy positions for extended periods of time but was capable of responding to release even after 170 years (i.e., gap facultative). In contrast, L. tulipifera appeared to rely on a strategy of rapid height and radial growth for canopy accession following large disturbances (i.e., gap obligate). The results of this study indicate the importance of using dendroecological techniques in the study of forest dynamics and species' growth strategies.

Estimating larval fish growth under size-dependent mortality: a numerical analysis of bias

2007 ◽  
Vol 64 (3) ◽  
pp. 554-562 ◽  
Author(s):  
Tian Tian ◽  
Øyvind Fiksen ◽  
Arild Folkvord
Keyword(s):  
Growth Rate ◽  
Longitudinal Data ◽  
Growth Rates ◽  
Mortality Rates ◽  
Growth Patterns ◽  
Cross Sectional ◽  
Larval Phase ◽  
Size Dependent ◽  
Recruitment Success ◽  
Dependent Mortality

The early larval phase is characterized by high growth and mortality rates. Estimates of growth from both population (cross-sectional) and individual (longitudinal) data may be biased when mortality is size-dependent. Here, we use a simple individual-based model to assess the range of bias in estimates of growth under various size-dependent patterns of growth and mortality rates. A series of simulations indicate that size distribution of individuals in the population may contribute significantly to bias in growth estimates, but that typical size-dependent growth patterns have minor effects. Growth rate estimates from longitudinal data (otolith readings) are closer to true values than estimates from cross-sectional data (population growth rates). The latter may produce bias in growth estimation of about 0.03 day–1 (in instantaneous, specific growth rate) or >40% difference in some situations. Four potential patterns of size-dependent mortality are tested and analyzed for their impact on growth estimates. The bias is shown to yield large differences in estimated cohort survival rates. High autocorrelation and variance in growth rates tend to increase growth estimates and bias, as well as recruitment success. We also found that autocorrelated growth patterns, reflecting environmental variance structure, had strong impact on recruitment success of a cohort.

Measurement of Age and Growth Rate in the Crustose Saxicolous Lichen Caloplaca Trachyphylla Using 14C Accelerator Mass Spectrometry

2000 ◽  
Vol 32 (4) ◽  
pp. 399-403 ◽  
Author(s):  
B. M. Clark ◽  
N. F. Mangelson ◽  
L. L. St. Clair ◽  
L. B. Rees ◽  
G. S. Bench ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Growth Rate ◽  
Growth Curve ◽  
Linear Dependence ◽  
Growth Rates ◽  
Accelerator Mass Spectrometry ◽  
Radial Growth ◽  
Age And Growth ◽  
Radial Position ◽  
Radial Growth Rate

AbstractSections of the crustose saxicolous lichen, Caloplaca trachyphylla, were dated using 14C accelerator mass spectrometry (AMS). The data show a stron linear dependence of radial position on time (r=0.993), suggesting a constant radial growth rate. This specimen had averaged a marginal growth rate of 1.48 mm/year. Extrapolation of the growth curve yields a thallus age of 20 years. These data demonstrate the feasibility of using AMS technology to precisely date lichen tissues and determine growth rates of lichen thalli.

scholarly journals A universal growth limit for circular lichens

2018 ◽  
Vol 15 (143) ◽  
pp. 20180063 ◽  
Author(s):  
Agnese Seminara ◽  
Joerg Fritz ◽  
Michael P. Brenner ◽  
Anne Pringle
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Radial Growth ◽  
Growth Dynamics ◽  
Growth Patterns ◽  
Radial Growth Rate ◽  
Growth Limit ◽  
Over Time ◽  
Circular Disks ◽  
Lichen Growth

Lichens fix carbon dioxide from the air to build biomass. Crustose and foliose lichens grow as nearly flat, circular disks. Smaller individuals grow slowly, but with small, steady increases in radial growth rate over time. Larger individuals grow more quickly and with a roughly constant radial velocity maintained over the lifetime of the lichen. We translate the coffee drop effect to model lichen growth and demonstrate that growth patterns follow directly from the diffusion of carbon dioxide in the air around a lichen. When a lichen is small, carbon dioxide is fixed across its surface, and the entire thallus contributes to radial growth, but when a lichen is larger carbon dioxide is disproportionately fixed at the edges of an individual, which are the primary drivers of growth. Tests of the model against data suggest it provides an accurate, robust, and universal framework for understanding the growth dynamics of both large and small lichens in nature.

scholarly journals Transition Dates from Earlywood to Latewood and Early Phloem to Late Phloem in Norway Spruce

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 331
Author(s):  
Jožica Gričar ◽  
Katarina Čufar ◽  
Klemen Eler ◽  
Vladimír Gryc ◽  
Hanuš Vavrčík ◽  
...  
Keyword(s):  
Climate Change ◽  
Growth Rate ◽  
Sensitivity Analysis ◽  
Norway Spruce ◽  
Radial Growth ◽  
Wood Properties ◽  
Growth Patterns ◽  
Cambial Cell ◽  
The Czech Republic ◽  
Specific Contribution

Climate change will affect radial growth patterns of trees, which will result in different forest productivity, wood properties, and timber quality. While many studies have been published on xylem phenology and anatomy lately, little is known about the phenology of earlywood and latewood formation, also in relation to cambial phenology. Even less information is available for phloem. Here, we examined year-to-year variability of the transition dates from earlywood to latewood and from early phloem to late phloem in Norway spruce (Picea abies) from three temperate sites, two in Slovenia and one in the Czech Republic. Data on xylem and phloem formation were collected during 2009–2011. Sensitivity analysis was performed to determine the specific contribution of growth rate and duration on wood and phloem production, separately for early and late formed parts. We found significant differences in the transition date from earlywood to latewood between the selected sites, but not between growth seasons in trees from the same site. It occurred in the first week of July at PAN and MEN and more than two weeks later at RAJ. The duration of earlywood formation was longer than that of latewood formation; from 31.4 days at PAN to 61.3 days at RAJ. In phloem, we found differences in transition date from early phloem to late phloem also between the analysed growth seasons; from 2.5 weeks at PAN to 4 weeks at RAJ Compared to the transition from earlywood to latewood the transition from early phloem to late phloem occurred 25–64 days earlier. There was no significant relationship between the onset of cambial cell production and the transition dates. The findings are important to better understand the inter-annual variability of these phenological events in spruce from three contrasting temperate sites, and how it is reflected in xylem and phloem anatomy.

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