scholarly journals Living (and reproducing) on the edge: reproductive phenology is impacted by rainfall and canopy decline in a Mediterranean eucalypt

2016 ◽  
Vol 64 (2) ◽  
pp. 129 ◽  
Author(s):  
T. L. Moore ◽  
K. X. Ruthrof ◽  
M. D. Craig ◽  
L. E. Valentine ◽  
G. E. St J. Hardy ◽  
...  
Keyword(s):  
Reproductive Effort ◽  
Insect Herbivory ◽  
Flowering Phenology ◽  
Climatic Conditions ◽  
Annual Rainfall ◽  
Reproductive Phenology ◽  
Ambient Temperatures ◽  
Reproductive Cycles ◽  
Individual Trees ◽  
Tree Condition

Many of the worlds’ forests and woodlands are currently showing symptoms of declining condition due to a range of factors, including changing climatic conditions, drought and insect herbivory. Altered abiotic and biotic conditions can influence the condition of trees that can, in turn, affect tree reproductive cycles. However, the potential impact of tree decline on reproductive cycles has rarely been examined. This study investigated the influence of canopy condition on the reproductive cycle of Eucalyptus wandoo Blakely in south-western Australia. Canopy and seed trap monitoring were used to assess bud production, flowering, fruiting and seed fall over 12 months at 24 sites across two locations (Dryandra Woodland and Wandoo Conservation Park). Time since last fire, rainfall, ambient temperatures and the condition of individual trees were recorded. We found that bud production, flowering and fruiting was correlated with tree condition: healthier trees were generally associated with higher reproductive effort. Time since last fire was also strongly related to the reproductive efforts at both locations. Declining annual rainfall and increased temperatures also impact on reproduction, made evident by the aborted flowering in Dryandra Woodland. Decline in tree condition, coupled with changes in climate, have major implications for flowering phenology of this species and have the potential to alter reproductive effort, recruitment and future population dynamics. Consideration of these issues should be incorporated into the conservation management of E. wandoo and similar Eucalypt species.

scholarly journals Seasonality of weather and phenology of reproductive organs of flower of sour cherry cultivars in Hungarian climatic conditions

2009 ◽  
Vol 15 (1-2) ◽  
Author(s):  
H. G. Davarynejad ◽  
M. Ansari ◽  
T. Szabó ◽  
J. Nyéki ◽  
Z. Szabó
Keyword(s):  
Sour Cherry ◽  
Flowering Phenology ◽  
Reproductive Organs ◽  
Climatic Conditions ◽  
High Variability ◽  
Prunus Cerasus ◽  
Reproductive Phenology ◽  
Environmental Cues ◽  
Development Patterns ◽  
Seasonal Responses

Sour cherry (Prunus cerasus L.) is one of the most important fruit crop grown in Hungary, The flowering phenology and pollen shedding/stigma viability ratio, in an effort to elucidate the reproductive phenology of nine economically important sour cherry cultivars (Érdi bőtermő, Debreceni bőtermő, Csengődi, Kántorjánosi 3. Pándy 279. Úfehértói fürtös, Petri, Éva, and Oblacsinszka) all widespread in the Hungary, was studied at Újfehertó climatic condition. The main aims were to investigate how possible environmental cues influence timing and development of phenophases and whether different cultivars have different seasonal responses to these cues. Likely effects of climatic changes on phenological development patterns were also considered. Our results revealed important aspects of the reproductive biology of sour cherry flowers. The amplitude of the phenophase "beginning of blossoming" between cultivars did not exceed 6 days. There is maximum 3 days difference in blooming length of different direction in each cultivar. Pándy 279 showed high variability when the position of flowers changed on the tree shoots. Újfehértói fürtös was stable in all four directions of tree. The pollen shedding period and stigma viability ratio was well synchronous. Pollen shedding phenomenon occurred in the range limitation of secretary activity of stigmas in all five cultivars. Distribution of pollen shedding over the secretary activity of stigmas is almost good. In all five cultivars maximum pollen shedding occurred about the high temperature part of the day.

scholarly journals Exploratory Studies on Occurrence and Potential Benefits of High Fruit Yielding Reproductive Phenophasic Variants of Pithecellobium dulce in Augmenting Fruit Based Semi-arid Agro Forestry Systems

2019 ◽  
pp. 1-17
Author(s):  
Jai Prakash Narayan
Keyword(s):  
Genetic Diversity ◽  
Natural Population ◽  
Tree Species ◽  
Flowering Phenology ◽  
Reproductive Behaviour ◽  
Arid Climate ◽  
Reproductive Phenology ◽  
Study Sites ◽  
Individual Trees ◽  
Semi Arid

Background: Pithecellobium dulce is a multipurpose legume tree species of high ecological significance. Several reports indicate existence of huge genetic diversity within the natural population of the species. Various morphological parameters have been used to assess intra species genetic diversity, however, there is no report available so far on diversities in reproductive phenology of P. dulce of semi-arid or arid climate. Methods: The present paper is based on assessment of diversity in flowering phenophases through construction of phenological calendar incorporating temporally observable morpho-phenotypic descriptors for reproductive behaviour of individual trees comprising natural population of the species at designated study sites during a period of three years. The study was carried out during September, 2015 and March, 2019 at Ajmer, Rajasthan, India. Data were periodically obtained and statistically analyzed. Results: Majority of trees of flowering stage (89.94%) exhibited normal or winter blooms in which flowering was initiated in almost synchronized manner during December; 10.05% of normal blooming trees inconsistently showed additional early or autumn blooms during either September or October or November; 2.58% of trees exhibited early blooms in which flowering was consistently initiated in the month of September in addition to normal blooms. The overall production and availability of fresh fruits in early-cum-normal episodic blooming trees were greater as compared to only normal blooming trees. Though, the numerical fruit productivity in winter blooms was superior to autumn, the pomometric characteristics were inferior in former in early-cum-normal episodic blooming trees. Conclusion: The methodology is a novel experimental approach to assess diversities in reproductive phenology of seed raised population of high value fruit bearing economically important tree species. The present work explores agronomically valuable variants of P. dulce and also reports causes of appearance of persistent fruits and sporadic in-situ germination of seeds. Based on above findings, the paper also makes evolutionary predictions that how a shift in flowering phenology of P. dulce as exhibited by the elite variants could have long-term implications for reshaping of future landscapes of semi-arid or arid climate. Conclusively, Winter to autumn phenophasic shift in flowering in P. dulce is economically productive, evolutionarily progressive, and environmentally well cued partial retrieval under semi-arid conditions. Moreover, the phenophasic variants could serve as candidate plus trees that deserve out of the season floral management and clonal propagation, thereby the species may get a fillip to status up gradation from minor fruits to major fruit category.

scholarly journals Adaptive genetic variation at three loci in South African vervet monkeys (Chlorocebus pygerythrus) and the role of selection within Primates

2018 ◽  
Author(s):  
Willem G Coetzer ◽  
Trudy R Turner ◽  
Christopher A Schmitt ◽  
J Paul Grobler
Keyword(s):  
Genetic Variation ◽  
South African ◽  
Vervet Monkey ◽  
Climatic Conditions ◽  
Primate Species ◽  
Annual Rainfall ◽  
Future Research ◽  
Vervet Monkeys ◽  
Adaptive Genetic Variation ◽  
Chlorocebus Pygerythrus

Vervet monkeys (Chlorocebus pygerythrus) are one of the most widely distributed non-human primate species found in South Africa. They occur across all the South African provinces, inhabiting a large variety of habitats. These habitats vary sufficiently that it can be assumed that various factors such as pathogen diversity could influence populations in different ways. In turn, these factors could lead to varied levels of selection at specific fitness linked loci. The Toll-like Receptor (TLR) gene family, which play an integral role in vertebrate innate immunity, is a group of fitness linked loci which has been the focus of much research. In this study, we assessed the level of genetic variation at partial sequences of two TLR loci (TLR4 and 7) and a reproductively linked gene, acrosin (ACR), across the different habitat types within the vervet monkey distribution range. Gene variation and selection estimates were also made among 11 – 21 primate species. Low levels of genetic variation for all three gene regions were observed within vervet monkeys , with only two polymorphic sites identified for TLR4, three sites for TLR7 and one site for ACR . TLR7 variation was positively correlated with high mean annual rainfall, which was linked to increased pathogen abundance. The observed genetic variation at TLR4 might have been influenced by numerous factors including pathogens and climatic conditions. The ACR exonic regions showed no variation in vervet monkeys, which could point to the occurrence of a selective sweep. The TLR4 and TLR7 results for the among primate analyses was mostly in line with previous studies, indicating a higher rate of evolution for TLR4. Within primates, ACR also showed signs of positive selection, which was congruent with previous reports on mammals. Important additional information to the already existing vervet monkey knowledge base was gained from this study, which can guide future research projects on this highly researched taxon as well as help conservation agencies with future management planning involving possible translocations of this species.

scholarly journals The correlation between the changes in climate, the intensity of spruce decline and the abundance of of spruce bark beetles in 'Golija' Nature Park

2016 ◽  
pp. 59-68
Author(s):  
Mara Tabaković-Tošić ◽  
Marija Milosavljević
Keyword(s):  
Bark Beetles ◽  
Ips Typographus ◽  
Climatic Conditions ◽  
Management Units ◽  
Spruce Bark ◽  
Spruce Decline ◽  
Nature Park ◽  
Individual Trees ◽  
Conifer Trees ◽  
Pheromone Dispensers

The paper presents the results of the research on the correlation between changes in microclimate, the intensity of spruce decline and active abundance of its two economically most significant harmful insects-eight-toothed (Ips typographus) and six-toothed (Pityogenes chalcographus) spruce bark beetles (Coleoptera: Curculionidae) in Golija Nature Park whose pure and mixed conifer stands are dominated by spruce. The route method and ocular inspection were applied to study the presence and determine the intensity of spruce decline-both of individual trees and groups of trees in the management units of Dajićke planine, Kolješnica, Golija and Brusničke šume. Population dynamics of the two species of bark beetles and their active abundance were monitored by the method of trapping with barrier traps and the use of combined pheromone dispensers-PCIT Ecolure. Although the decline of individual conifer trees, primarily of spruce, had already been present in certain areas of these management units for several decades, it reached epidemic proportions due to extreme adverse climatic conditions in the period between 2011 and 2012 and culminated in 2015. A large number of physiologically weakened trees raised the population levels of secondary harmful insects and the number or the active abundance of the two investigated species of insects reached a peak in 2016. The inability to take appropriate and timely remedial measures in the areas under stricter protection regimes greatly contributed to this situation.

scholarly journals Aboveground Biomass Stockpile of Trees in Vallanadu Blackbuck Sanctuary, Peninsular India

2021 ◽  
Vol 16 (3) ◽  
pp. 755-763
Author(s):  
M. Nagaraj M. Nagaraj ◽  
M. Udayakumar
Keyword(s):  
Aboveground Biomass ◽  
Tamil Nadu ◽  
Basal Area ◽  
Single Species ◽  
Forest Tree ◽  
Annual Rainfall ◽  
Dry Forests ◽  
Peninsular India ◽  
Tree Inventory ◽  
Individual Trees

A forest tree inventory study was conducted in Vallanadu Black buck sanctuary, Tuticorin. The current study was conducted to assess tree density, species richness, basal area (BA) and aboveground biomass (AGB) stockpile. The study area has been classified as Southern Thorn Forest (SFT). One hundred square plots (total area 1 ha), each 10m × 10m (100 m2 each) laid randomly across study area. All live trees with ≥5 cm diameter at breast height (DBH) measured at 137 cm above the ground. As the whole, 1335 individual trees ≥5cm DBH recorded. A total number of 18 species recorded from 14 genera and 11 families in study area. The family Mimosaceae has maximum number of species (7 species) followed by Rhamnaceae (2 species), while 9 families had just single species’ each. The total basal area recorded was 22.046 m2 ha-1, while, the mean wood density (WD) of trees estimated as 0.70±0.093 g cm-3. Total amount of 50.065 Mg ha-1 present in STF. The contribution of different species in terms of total AGB varied significantly. Commiphora berryi stocked 45.13% (22.588 Mg ha-1) of AGB followed by A. planifrons (23.31%, 11.669 Mg ha-1), A. mellifera (7.233%, 3.621 Mg ha-1), whereas remaining 15 species collectively stocked 24.327% (12.187 Mg ha-1) AGB. The STF had a large number of trees compared to some dry forests within Tamil Nadu. Southern Thorn Forest endowed with a moderate number of trees species. Aboveground biomass stockpile of trees is comparable with the range recorded from Indian dry forests. The study area experiences lesser mean annual rainfall and >6 months dry season. Further, endowed with short-bole and smaller leaved trees, hence stocked a relatively lesser AGB in trees.

Effects of geographical and climatic factors on cystic echinococcosis in south-western Iran

2020 ◽  
Vol 94 ◽  
Author(s):  
A. Jamshidi ◽  
A. Haniloo ◽  
A. Fazaeli ◽  
M.A. Ghatee
Keyword(s):  
Land Cover ◽  
Cystic Echinococcosis ◽  
Geographical Information Systems ◽  
Climatic Factors ◽  
Weather Conditions ◽  
Climatic Conditions ◽  
Geographical Information ◽  
Annual Rainfall ◽  
Mean Annual Temperature ◽  
Western Iran

Abstract Cystic echinococcosis (CE) is caused by the larval form of Echinococcus granulosus that can cause serious health and economic problems in the endemic foci. CE is globally distributed in various climatic conditions from circumpolar to tropical latitudes. Iran is an important endemic area with a spectrum of weather conditions. The aim of this study was to determine the effects of geo-climatic factors on the distribution of livestock CE in south-western Iran (SWI) in 2016 to 2018. Data of livestock CE were retrieved from veterinary organizations of four provinces of SWI. The geo-climatic factors, including mean annual temperature (MAT), minimum MAT (MinMAT), maximum MAT (MaxMAT), mean annual rainfall (MAR), elevation, mean annual evaporation (MAE), sunny hours, wind speed, mean annual humidity (MAH), slope, frost days and land cover, were analysed using geographical information systems (GIS) approaches. The statistical analysis showed that MAR, frost days, elevation, slope and semi-condensed forest land cover were positively and MAE, MAT, MaxMAT, MinMAT and salt and salinity land cover were negatively correlated with CE occurrence. MAE was shown to be a predictive factor in the stepwise linear logistic regression model. In short, the current GIS-based study found that areas with lower evaporation were the main CE risk zones, though those with lower temperature and higher rainfall, altitude and slope, especially where covered with or in close proximity of semi-condensed forest, should be prioritized for consideration by health professionals and veterinarians for conducting control programmes in SWI.

Reproductive biology of the false coral snake Oxyrhopus guibei (Colubridae) from southeastern Brazil

2002 ◽  
Vol 23 (4) ◽  
pp. 495-504 ◽  
Author(s):  
Otavio Marques ◽  
Lígia Pizzatto
Keyword(s):  
Body Size ◽  
Reproductive Biology ◽  
Rainy Season ◽  
Reproductive Activity ◽  
Climatic Conditions ◽  
Southeastern Brazil ◽  
Coral Snake ◽  
Males And Females ◽  
Reproductive Cycles ◽  
Number Of Individuals

AbstractThe reproductive biology of the false coral snake, Oxyrhopus guibei, was studied through dissection of 496 specimens, combined with observations on captive individuals. Males mature with smaller body size than females, females attain much larger body size, and male-male combat is not expected. Clutch size ranged from 3 to 20, and was correlated with female length. Reproductive cycles in both males and females seem to be continuous, with vitellogenesis and spermatogenesis occurring throughout the year. Reproductive activity in both sexes decreased at the end of the rainy season possibly due to previous intense reproductive activity in more favorable climatic conditions. The smaller number of individuals collected at the end of the rainy season apparently occurs due to the decrease of reproductive activity of this snake.

scholarly journals Pollinator experience, neophobia and the evolution of flowering time

2008 ◽  
Vol 276 (1658) ◽  
pp. 935-943 ◽  
Author(s):  
Jessica Forrest ◽  
James D Thomson
Keyword(s):  
Frequency Dependence ◽  
Flowering Time ◽  
Environmental Changes ◽  
Flowering Phenology ◽  
Plant Population ◽  
Early Flowering ◽  
Reproductive Phenology ◽  
Pollinator Visitation ◽  
Pollinator Behaviour ◽  
Bee Foraging

Environmental changes, such as current climate warming, can exert directional selection on reproductive phenology. In plants, evolution of earlier flowering requires that the individuals bearing genes for early flowering successfully reproduce; for non-selfing, zoophilous species, this means that early flowering individuals must be visited by pollinators. In a laboratory experiment with artificial flowers, we presented captive bumble-bees ( Bombus impatiens ) with flower arrays representing stages in the phenological progression of a two-species plant community: Bees that had been foraging on flowers of one colour were confronted with increasing numbers of flowers of a second colour. Early flowering individuals of the second ‘species’ were significantly under-visited, because bees avoided unfamiliar flowers, particularly when these were rare. We incorporated these aspects of bee foraging behaviour (neophobia and positive frequency dependence) in a simulation model of flowering-time evolution for a plant population experiencing selection against late flowering. Unlike simple frequency dependence, a lag in pollinator visitation prevented the plant population from responding to selection and led to declines in population size. Pollinator behaviour thus has the potential to constrain evolutionary adjustments of flowering phenology.

scholarly journals Climatic and Altitudinal Influences on Variation in Macaca Limb Morphology

2011 ◽  
Vol 2011 ◽  
pp. 1-18 ◽  
Author(s):  
Karen J. Weinstein
Keyword(s):  
Partial Correlation ◽  
Principal Component ◽  
Interspecific Variation ◽  
Climatic Conditions ◽  
Ambient Temperatures ◽  
Interspecific Variations ◽  
Large Joint ◽  
Small Joint ◽  
High Elevations ◽  
Limb Morphology

This study compares limb lengths and joint diameters in the skeletons of six macaque species (Macaca assamensis, M. fascicularis, M. fuscata, M. mulatta, M. nemestrina, and M. thibetana) from a broad range of habitats and climates in order to test whether ambient temperatures, latitude, and altitude influence interspecific variation in limb morphology in this widely dispersed genus. Analysis of variance, principal component analysis, and partial correlation analysis reveal that species from temperate latitudes and high elevations tend to have short limbs and large joint diameters for their sizes while species from tropical latitudes and low elevations tend to have long limbs and small joint diameters. Interspecific variations in intra- and interlimb length proportions also reflect phylogeny and subtle differences in locomotion. The results of this study suggest that climatic conditions are important factors among many ecological variables that influence limb morphology in this geographically widespread genus.

scholarly journals Nonlinear flowering responses to climate: are species approaching their limits of phenological change?

2013 ◽  
Vol 368 (1624) ◽  
pp. 20120489 ◽  
Author(s):  
Amy M. Iler ◽  
Toke T. Høye ◽  
David W. Inouye ◽  
Niels M. Schmidt
Keyword(s):  
Regression Model ◽  
Plant Species ◽  
Plant Communities ◽  
Nonlinear Regression ◽  
Interannual Variation ◽  
Flowering Phenology ◽  
Climatic Conditions ◽  
Rate Of Change ◽  
Nonlinear Regression Model

Many alpine and subalpine plant species exhibit phenological advancements in association with earlier snowmelt. While the phenology of some plant species does not advance beyond a threshold snowmelt date, the prevalence of such threshold phenological responses within plant communities is largely unknown. We therefore examined the shape of flowering phenology responses (linear versus nonlinear) to climate using two long-term datasets from plant communities in snow-dominated environments: Gothic, CO, USA (1974–2011) and Zackenberg, Greenland (1996–2011). For a total of 64 species, we determined whether a linear or nonlinear regression model best explained interannual variation in flowering phenology in response to increasing temperatures and advancing snowmelt dates. The most common nonlinear trend was for species to flower earlier as snowmelt advanced, with either no change or a slower rate of change when snowmelt was early (average 20% of cases). By contrast, some species advanced their flowering at a faster rate over the warmest temperatures relative to cooler temperatures (average 5% of cases). Thus, some species seem to be approaching their limits of phenological change in response to snowmelt but not temperature. Such phenological thresholds could either be a result of minimum springtime photoperiod cues for flowering or a slower rate of adaptive change in flowering time relative to changing climatic conditions.

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