scholarly journals Population structure and spatial distribution of tucumã-do-pará (Astrocaryum vulgare Mart.) in Salvaterra, Marajó island, Pará

2021 ◽  
Vol 93 (suppl 3) ◽  
Author(s):  
GABRIELE N. FURTADO ◽  
PRISCILA S.M. SARMENTO ◽  
FLÁVIA C.A. LUCAS
2010 ◽  
Vol 7 (3) ◽  
pp. 327-329 ◽  
Author(s):  
Simon Fellous ◽  
Elsa Quillery ◽  
Alison B. Duncan ◽  
Oliver Kaltz

Parasitic infection can modify host mobility and consequently their dispersal capacity. We experimentally investigated this idea using the ciliate Paramecium caudatum and its bacterial parasite Holospora undulata . We compared the short-distance dispersal of infected and uninfected populations in interconnected microcosms. Infection reduced the proportion of hosts dispersing, with levels differing among host clones. Host populations with higher densities showed lower dispersal, possibly owing to social aggregation behaviour. Parasite isolates that depleted host populations most had the lowest impact on host dispersal. Parasite-induced modification of dispersal may have consequences for the spatial distribution of disease, host and parasite genetic population structure, and coevolution.


Ecography ◽  
1989 ◽  
Vol 12 (2) ◽  
pp. 163-172 ◽  
Author(s):  
Lars Hedenas ◽  
Tomas Herben ◽  
Hakan Rydin ◽  
Lars Soderstrom

2019 ◽  
Vol 76 (6) ◽  
pp. 1581-1590 ◽  
Author(s):  
Luke W J Cameron ◽  
William K Roche ◽  
Jonathan D R Houghton ◽  
Paul J Mensink

Abstract Porbeagles throughout the North Atlantic have experienced severe population decline through overfishing, with the northeastern population listed as critically endangered. Management of this population is constrained by the paucity of data on porbeagle population structure, distribution and behaviour in this region. Here we use a long-term (47 year) Irish capture-mark-recapture dataset to investigate the population structure, spatial distribution and seasonal movements of this species. From 1970–2017, a total of 268 sharks (9 recaptures) were ID tagged, with most individuals likely being juvenile based on length at maturity estimates (mean total length = 143.9 cm, SD = 35.4). Almost all captures were recorded at three distinct locations near angling hubs along the south, west and north coasts with catches peaking in August. Long-term trends in capture date indicated a shift towards earlier capture dates in the northern site (n = 153). Our findings suggest Irish waters may act as a persistent summer aggregation site for juveniles, which show evidence for seasonal site fidelity, returning to nearby locations between years. These findings demonstrate the utility of such programmes, which can be implemented, with minimal expense by engaging with the angling sector, to elucidate the population structure and distribution of wide-ranging fish species.


2011 ◽  
Vol 39 (2) ◽  
pp. 111-121 ◽  
Author(s):  
ANDRESSA BÁRBARA SCABIN ◽  
FLÁVIA REGINA CAPELLOTTO COSTA ◽  
JOCHEN SCHÖNGART

SUMMARYAmazonia is one of the world's leading suppliers of timber and the Amazonian timber industry is an important source of regional income, however the economic benefits of this market are associated with environmental damage, mainly when the wood is removed illegally. The Anavilhanas National Park, located in the Brazilian state of Amazonas, has been subjected to illegal logging and elaboration of control programmes requires knowledge of the distribution of timber species and the intensity of logging. This study examines the density and growth rate of the five most harvested tree species in the Park, the spatial distribution of illegal logging operations and their effects on population structure. In total, 2332 trees with diameter at breast height greater than 10 cm, as well as stumps of cut trees, were sampled, and dendrochronology was used to estimate growth rates. Some size classes of Virola surinamensis trees and species within the family Lauraceae decreased in abundance as harvesting intensity increased. Growth rates of the most abundant species of Lauraceae, Ocotea cymbarum, were high, indicating stands may recover quickly when harvesting stops. The population structure of Calophyllum brasiliense showed no negative effects due to logging, but its low growth rate and stand distribution suggest that continued exploitation may endanger these populations. Logging had no detectable negative effects on the size structure of populations of Macrolobium acaciifolium or Hevea spp., and their high growth rates suggest that they will not be threatened by current logging rates. Overall growth rates in the Anavilhanas archipelago are higher than those recorded in other black-water floodplain forest (igapó). Logging of most species (except Lauraceae spp., which have the highest market value) is concentrated in the southern region of the Park, which has more human settlements close by. There was no general relationship between harvesting intensity and geographic distance to human settlements, but there was a tendency for harvesting to be higher in sites with concentrations of trees of high market value. Potential strategies to control illegal logging activities in the Anavilhanas archipelago include encouragement of sustainable logging in Park buffer zones and stimulation of ecotourism initiatives in the southern region of the Park. Ecotourism development can provide an economic alternative to illegal logging for local communities and inhibit logging by increasing vigilance.


PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244372
Author(s):  
Naim Bro ◽  
Marcelo Mendoza

Based on a geocoded registry of more than four million residents of Santiago, Chile, we build two surname-based networks that reveal the city’s population structure. The first network is formed from paternal and maternal surname pairs. The second network is formed from the isonymic distances between the city’s neighborhoods. These networks uncover the city’s main ethnic groups and their spatial distribution. We match the networks to a socioeconomic index, and find that surnames of high socioeconomic status tend to cluster, be more diverse, and occupy a well-defined quarter of the city. The results are suggestive of a high degree of urban segregation in Santiago.


Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2127
Author(s):  
Marina García-Alfonso ◽  
Thijs van Overveld ◽  
Laura Gangoso ◽  
David Serrano ◽  
José A. Donázar

Recent changes in European legislation have legalized the abandonment of carcasses around livestock farms, but our understanding of how vultures exploit these semi-predictable food sources is still very limited. For filling this gap, we determine the individual and ecological drivers influencing vulture visits to farms. We assessed the effects of individual characteristics of both birds and farms on the frequency of vultures’ visits to livestock facilities using data collected from 45 GPS-tagged Egyptian Vultures (Neophron percnopterus) and 318 farms (>94% of livestock) on Fuerteventura Island, Spain. Farms were more visited during the vultures’ breeding season. Farms located closer to highly predictable feeding places (i.e., vulture restaurants and garbage dumps) or with more available feeding resources were visited by more vultures, whereas those located close to roads and vultures’ breeding territories received fewer visits. Younger territorial birds visited a farm more frequently than older territorial ones, whereas older non-territorial individuals concentrated those visits on farms closer to their activity core areas compared with younger ones. Our findings indicate that visits to farms were determined by their spatial distribution in relation to the age-specific birds’ activity centers, the availability of carcasses, seasonality, and individual characteristics of vultures. These interacting factors should be considered in vulture conservation, avoiding very general solutions that ignore population structure.


2020 ◽  
pp. 3000-3005
Author(s):  
Priscila Bezerra de Souza ◽  
Bruno Aurélio Campos Aguiar ◽  
Giuseppe Varaschim Neto ◽  
Euclides Figueredo Fonseca ◽  
Bárbara Maria Martins Santos ◽  
...  

The aim of this work was to analyze the population structure and the spatial distribution of Copaifera langsdorffii Desf. in two areas of the Cerrado biome. The study was carried out in two physiognomies of the Cerrado biome: cerrado sensu stricto and cerradão, both located in the southern region of the state of Tocantins. The spatial distribution was evaluated using Morisita and dispersion indices, as well as the population structure of C. langsdorffii. We quantified 318 individuals of C. langsdorffii in the two studied areas. There were 200 individuals sampled in the cerrado sensu stricto and 118 in the area of cerradão. Regarding the type of spatial distribution of individuals of C. langsdorffii, the value found for the Morisita index was 2.67 in the physiognomy of cerrado sensu stricto, suggesting grouped spatial distribution (I >1). The dispersion index calculation showed that, in fact, the spatial distribution of the individuals sampled in the two areas was the grouped type; for the area of cerrado sensu stricto, the variance (S2) found was 24.21 and for the cerradão it was 9.67, higher than their means 10.00 and 9.67 respectively. By analyzing the age structure of the population of C. langsdorffii, we found a typical trend of the inverted-J curve, suggesting that the areas studied are self-regenerating communities composed of young and developing individuals.


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