Time filter

Source Type

Xalapa de Enríquez, Mexico

Najera-Hillman E.,COSTASALVAJE A.C | Mandujano S.,Institute Ecologia Ac Inecol
Wildlife Biology in Practice | Year: 2013

Stable isotope analyses of tissues and faeces offer an alternative to study the dietary ecology in wild animal populations. Faecal isotope analyses are advantageous because samples are easy to obtain in the field, their isotopic composition is related to the food ingested and allow for documenting short-term diet variability. Therefore, we estimated diet-faeces trophic shifts in white-tailed deer (Odocoileus virginianus) fed on a constant diet. The observed diet-faeces trophic shifts (0.81% for δ13C and 2.13‰ for δ15N) were different to the trophic shifts reported for other herbivores. However, our estimates proved to be useful when applied to a mixing model to quantify the contributions of multiple food sources to the deer's diet. Our diet-faeces trophic shift estimates are reliable measurements that can be used to expand the potential of stable isotope analyses in white-tailed deer dietary ecology studies. © 2013 E. Nájera-Hillman & S. Mandujano. Source

Peters R.,TU Dresden | Vovides A.G.,TU Dresden | Vovides A.G.,Institute Ecologia Ac Inecol | Luna S.,TU Dresden | And 2 more authors.
Ecological Modelling | Year: 2014

Models based on allometric responses to competing neighbours and environmental conditions in mangrove forests are increasingly available. However, the improvement of these models requires a mechanistic understanding of how individual trees allocate biomass. This study introduces a new tree model (BETTINA) focusing on this issue. It is designed to investigate the response of trees in terms of biomass allocation patterns to environmental conditions. Additionally, it is suitable as a component of an individual-based mangrove stand model. BETTINA describes the plasticity of trees in growth patterns depending on their below-ground resource uptake. In contrast to the existing mangrove stand models, BETTINA focusses explicitly on the processes leading to variation in resource availability. Based on the physical principle of osmotic potential of solutions, the direct influence of salinity on plant water availability is considered. Allometric model parameters are not restricted to only the above-ground measures of trees' traits (such as stem diameter and height), but also characterize below-ground biomass. Within BETTINA these measures are not limited to predefined empirical maximum values, but are the result of and depend on environmental conditions.The model is suitable to explain allometric measures and relations in dependence on total plant size and environmental conditions (for now salinity and light), and has a great potential for a physiologically and physically based improvement of plant component related biomass estimations. © 2014 Elsevier B.V. Source

Twenty years after being established, the ILTER network embraces more than 600 groups from 37 countries. The ecological research at the ILTER network has moved from a merely ecological focus toward a more socio-ecological approach. The network is now more committed to social needs and with higher international presence. An important challenge in the next years will be to encourage a more socioecosystem and trans-disciplinary research. Its wide and flexible research agenda, along with its particular commitment from its groups to work on specific sites for a long time (know as “site based research”), makes ILTER particularly useful and relevant in dealing with the current environmental crisis. The network has incorporated tools and protocols to improve collaboration, such as common metadata management protocols and a multilingual information research system. It is still necessary to improve the efficiency of information delivery to the general public, promoting a more integrated, useful, comprehensive and local context information. The network should also keep promoting “bottom up” initiatives as well as the participation of students and early career scientists. We cannot expect the same level of participation between networks. However, we do expect the same level of commitment and should promote the evaluation of the national networks; not as an exclusion process, but as a mechanism to stimulate collaboration, as well as for an early detection of problems of integration. The ILTER network should keep increasing its geographic presence promoting the integration of single affiliated sites as seeds for the development of future national networks. © 2014, Universidad Austral de Chile. All Rights reserved. Source

Goldarazena A.,Institute Ecologia Ac Inecol | Infante F.,Colegio de Mexico | Ortiz J.A.,Colegio de Mexico
Florida Entomologist | Year: 2014

Approximately 6000 species of Thysanoptera have been described worldwide. They are particularly diverse in the Neotropics, living in a wide range of environments. Although many species of thrips are well known as inhabitants of cultivated plants, there are others that are abundant in other types of habitats. In the present study we conducted a survey in the "Biosphere Reserve of Volcan Tacana" with the main objective to know the native fauna of thrips. The results confirm the presence of 112 species in 52 genera and 4 families. Our survey indicates that this reserve contains a great biodiversity of Thysanoptera. A full check-list of species is provided. Source

Moo-Llanes D.,Instituto Nacional Of Salud Publica Insp | Ibarra-Cerdena C.N.,Instituto Nacional Of Salud Publica Insp | Ibarra-Cerdena C.N.,CINVESTAV | Rebollar-Tellez E.A.,Autonomous University of Nuevo Leon | And 3 more authors.
PLoS Neglected Tropical Diseases | Year: 2013

Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases. © 2013 Moo-Llanes et al. Source

Discover hidden collaborations