Abstract:
:The spatial distribution of individuals is a fundamental property of most species and constitutes essential information for the development of restoration and conservation strategies, especially for endangered plant species. In this paper we describe the spatial distribution of different size classes of the endangered tropical tree Guaiacum sanctum and the effect of canopy cover on spatial aggregation. Adult G. sanctum were located and mapped in a 50 ha plot in Palo Verde National Park, Costa Rica. Seedlings, saplings and juveniles were mapped to the nearest centimetre and permanently marked in three 50 x 50 m subplots. Within each subplot spatial aggregation was assessed using Ripley's K statistic and canopy opening readings were performed every 5 m using a densitometer. Kriging spatial interpolation and Monte Carlo simulations were used to determine if average canopy cover differed among size classes. Individuals of G. sanctum were spatially aggregated at all size classes with seedlings being the most frequent size class in all subplots. Seedlings were found predominantly in areas with significantly higher canopy cover. In contrast, juveniles were more likely found in areas with higher light availability. The high number of seedlings, saplings, and juveniles relative to adults suggests that populations of G. sanctum in PVNP are expanding. Light availability and canopy structure are important factors shaping the spatial distribution of this species. The contemporary demographic structure of G. sanctum is dependent on forest gap dynamics and changes in human disturbance during the past 25 years.
journal_name
Rev Biol Tropjournal_title
Revista de biologia tropicalauthors
Fuchs EJ,Robles T,Hamrick JLdoi
10.15517/rbt.v61i3.11981subject
Has Abstractpub_date
2013-09-01 00:00:00pages
1521-33issue
3eissn
0034-7744issn
2215-2075journal_volume
61pub_type
杂志文章abstract::Because of their slow growth, shade-tolerant species remain exposed to foliar damage long before reproductive age. Foliar damage can be controlled through synchronous leaf production and specialized phytochemical strategies. In this study, the dynamics of foliar damage in different cohorts of seedlings were evaluated ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2008-09-01 00:00:00
abstract::The Black Brant is a common inhabitant of the Western Artic American tundra, which migrates to Southern Pacific coasts during the winter season. Approximately, 31000 birds (31%) constitute the Mexican population of Brants at Guerrero Negro, Ojo de Liebre, and Exportadora de Sal lagoon complex; nevertheless, there is l...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-06-01 00:00:00
abstract::Lichenized fungi or lichens are organisms that have been little studied in the tropics and which distribution is affected by microenvironmental factors and substrate characteristics. The present study aimed to identify phorophyte specificity and microenvironmental preferences of corticolous lichens in five phorophyte ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2012-06-01 00:00:00
abstract::River floodplains have a high biological diversity that is intensely influenced by vegetation dynamics, changes in space and time scales, and the river's hydrological regime. The vegetation composition of the medium and lower Paraná River has been analyzed previously, with different approaches and criteria that cannot...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2010-06-01 00:00:00
abstract::The aim of this work was to analyze histologically and histometrically the sublingual gland of mice infected with the RAL strain of T. cruzi, according to the sex. Swiss mice (Mus musculus) were inoculated with 2 x 10(4) blood trypomastigotes of the RAL strain of T. cruzi. In the peak of the parasitemia (12th day) the...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2008-06-01 00:00:00
abstract::Huperzia brevifolia is one of the dominant species of the genus Huperzia living in paramos and superparamos from the Colombian Andes. A detailed study of the sporangium's ontogeny and sporogenesis was carried out using specimens collected at 4200m above sea level, in Parque Natural Nacional El Cocuy, Colombia. Small p...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2009-12-01 00:00:00
abstract::Female resistance behavior that occurs prior to intromission does not by itself imply forced copulation. Such behavior may function instead as a test of the male in order to favor some males over others, or to induce the male to desist. Thus, male persistence and forcefullness may sometimes be better described as pers...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2002-06-01 00:00:00
abstract::We analyzed the diet and feeding habits of the fishes Heterandria bimaculata and Poecilia sphenops. Specimens were captured monthly in "Los Carros" damp, Morelos, Mexico (18 degrees 37' N, 98 degrees 43' W). We quantified gut content by the numerical method and by the frequency of occurrence method; and used the MacAr...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2007-06-01 00:00:00
abstract::Six Costa Rican communities of different ecological settings were selected for the study of food intake in children under 5 years of age. Intake was expressed as calorie and protein adequacy. Calorie deficiency was more prevalent than protein defficiency. Practically there were no differences in adequacy by age, altho...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1978-12-01 00:00:00
abstract::We studied the composition and seasonal variation of the diet of the capybara (Hydrochaeris hydrochaeris) in the flooded savannas of Caño Limón, Colombia. This was achieved by direct observation of the consumption patterns of these animals. The capybaras only consumed plants, and their diet included 89 species of 22 f...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2003-06-01 00:00:00
abstract::Abstract: Attacks by big cats on livestock are one of the major causes of human-felid conflicts and, therefore, an important factor in the conservation of these species. It has been argued that a reduction in natural prey abundance promotes attacks on domestic species, but few studies have tested this statement, and s...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v62i4.13199
更新日期:2014-12-01 00:00:00
abstract::Two laboratory maintenance systems of Trypanosoma rangeli were compared. The maintenance by weekly subinoculations in Tobie's culture medium and the intrafemoral inoculation of Rhodnius prolixus with cultured flagellates, resulted in loss of infectivity of the metacyclic salivarian trypomastigotes for mice, ten months...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1986-06-01 00:00:00
abstract::Abstract: Histology of gill, liver and kidney in juvenile fish Colossoma macropomum exposed to three temperatures. Water temperature is an important factor that affects growth and antioxidant enzyme activities in fish, and when adverse, it may trigger diseases in fish populations. C. macropomum is a freshwater neotrop...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-06-01 00:00:00
abstract::A new genus and two species of Melolonthinae from Honduras and Nicaragua are described. A phylogenetic analysis, carried out using morphological characters, suggests that Catrachia is a strongly supported monophyletic group. Catrachia is therefore established as a new genus, constituted by two new species, Catrachia m...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v54i2.13910
更新日期:2006-06-01 00:00:00
abstract::The diet ofa neotropical fish species (Creagrutus bolivari) was studied using different methods: the Cortés 1997 graphic method and two relative importance indexes, one designed by George and Hadley in 1979 (% RIi) and another proposed by Cortés in 1997 (% IRIi). Only discrete prey (aquatic and terrestrial invertebrat...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2006-12-01 00:00:00
abstract::Observations about the floral biology and the reproductive system of Macroptilium fraternum were made in two populations in Argentina, with different edaphic conditions, situated at the southern area of distribution of the species. The coexistence of two kind of flowers in the same plant was detected in both populatio...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2003-06-01 00:00:00
abstract::Community structure and composition are dictated by evolutionary and ecological assembly processes which are manifested in signals of, species diversity, species abundance and species relatedness. Analysis of species coexisting relatedness, has received attention as a tool to identify the processes that influence the ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v64i3.18806
更新日期:2016-09-01 00:00:00
abstract::The anti-inflammatory properties of Loasa speciosa and Loasa triphylla (Loasaceae), Urtica leptuphylla and Urera baccifera (Urticaceae), and Chaptalia nutans (Asteracene) were studied using the carregeenan induced rat paw edema model. Aqueous extracts of each plant were made according to the ethnobotanical use. The hi...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::In Egypt, Biomphalaria alexandrina is the intermediate host for Schistosoma mansoni. The fates of Schistosoma miracidia in the snails varies between different species of Biomphalaria. The internal defense system is one of the factors that influence the susceptibility pattern of the snails. The interaction between Biom...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v60i3.1771
更新日期:2012-09-01 00:00:00
abstract::We observed the mating behavior of the neck-banded snake Scaphiodontophis annulatus (a common species of colubrid in the South Pacific of Costa Rica) in the pre-montane wet forest of Las Cruces Biological Station (San Vito de Java, Costa Rica). Three S. annulatus were observed during courtship between 10-12 AM in a pa...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v54i2.13940
更新日期:2006-06-01 00:00:00
abstract::In Costa Rica, cervical cancer is the second most common female cancer, despite accessibility of screening through the universal health care system. There is little understanding of knowledge levels of the adolescent population on cervical cancer, although this population is the most exposed to risk factors. This stud...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v62i3.14063
更新日期:2014-09-01 00:00:00
abstract::The study presents an interactive descriptive tool (MONRATE) for calculating and predicting reinfection rates and time of Ascaris lumbricoides following mass chemotherapy. The implementation was based on the theoretical equation published by Hayashi in 1977, for time-prevalence: Y=G [1-(1-X)(N-R)] as modified by Jong-...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v55i3-4.5951
更新日期:2007-09-01 00:00:00
abstract::Size and fecundity observations of pea crab (Juxtafabia muliniarum) from the paleal cavity of the oyster Saccostrea palmula were made from May 1998 to May 1999. Infestation frequency was 18.52% in a sample of 540 oysters. Of 136 pea crabs, 36% were couples, 60% were single females and 4% were single males. The mean ca...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2001-09-01 00:00:00
abstract::The advancing agricultural frontier has led to an important loss of natural habitats, with significant consequences for biodiversity. The demography for two species of anurans, Physalaemus biligonigerus and Rhinella arenarum, both associated with agricultural systems in the central region of the C6rdoba Province, were...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2013-09-01 00:00:00
abstract::The euglossine bee Eulaema nigrita plays an important role for the pollination of native and economically important plants, such as the sweet passion-fruit Passiflora alata. E. nigrita uniquely collects the nectar from the flowers of P. alata, nevertheless, it needs to visit other plants to collect pollen, nectar and ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v60i4.2073
更新日期:2012-12-01 00:00:00
abstract::Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v57i1-2.11360
更新日期:2009-03-01 00:00:00
abstract::The diversity of chondrychthyans in Mexico is described. The fauna is composed by 214 species (111 sharks, 95 rays and 8 chimaeras) and represents 17.3 % of the total number of species recorded worldwide. The families with the highest diversity comprise: Rajidae (14.5 %), Carcharhinidae (12.1 %), Pentanchidae, Triakid...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:
更新日期:2016-12-01 00:00:00
abstract::Most laboratory assessments of toxicity and bioaccumulation of heavy metals have been concentrated on the accumulation of these metal ions when exposed singly to the test organisms. However, under the natural environmental settings, the metals are never present in isolation and may interact with each other, therefore ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v54i3.12791
更新日期:2006-09-01 00:00:00
abstract::Schistosomiasis remains a disease of major global public health concern since it is a chronic and debilitating illness. The widely distributed Schistosoma mansoni that causes intestinal schistosomiasis represents a great threat. Its world-wide distribution is permitted by the broad geographic range of the susceptible ...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v64i4.21668
更新日期:2016-12-01 00:00:00
abstract::The food habits of Trachinotus paitensis, in San Ignacio Lagoon B.C.S., Mexico, were investigated. We observed that T. paitensis is carnivorous, feeding mainly on benthic invertebrates (the gastropods Anachis spp., Bittium spp., and the crustacean larvae). We concluded that T. paitensis is an opportunist predator that...
journal_title:Revista de biologia tropical
pub_type: 杂志文章
doi:10.15517/rbt.v52i1.14762
更新日期:2004-03-01 00:00:00