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[en] The study object is to identify biological corridors as recovery time strategy in highly fragmented landscapes through tools of Geographic Information Systems, taking as a case study of microcuenca La Balsa, Marinilla Town. GIS tools such as V- Late, allowed assessing landscape structure through statistical analysis of forest fragments of local biodiversity importance, that from a cost raster that allowed the tracing of the biological corridor using Cost weight, shortest path and a buffer width of 100 meters as optimal for the use of certain animal species such as small and medium-sized mammals and birds. This allowed us to propose the biological corridor that will allow functional linkage of strategic ecosystems of the watershed and the recovery time, preservation and protection of biodiversity in the areas. Importantly, the use of birds as indicators of biodiversity and ecosystem disruption with which you intend to measure susceptibility to fragmentation, risk status due to loss of habitat and migratory frugivorous species which are sensitive to these changes and allow monitoring by evaluating the success of the biological corridor, because although the present study took a hypothetical data, the use of these indicators are intended to establish the need to identify key species of flora and fauna that allow for monitoring and verifying the success or otherwise of posed recovery strategy.
[en] The predominance of economic assessments regarding the value of natural resources has caused a sub-valuing of the real benefits which societies can obtain from nature. This is due to a lack of knowledge about the complexity of ecological functions, as well as a dismissal of the integrated relations of the sub-systems which make up the environment. It is therefore necessary to establish conceptual bridges between environmental sciences to fill in the gaps in economic valuation methods by recurring to diverse measuring scales, participation from the different actors involved, and a principle of precaution regarding the limits of nature. This paper explores the concepts of value and economic valuation methods from the perspectives of Environmental Economics and Ecological Economics. It then proposes an integration of valuing methodologies which take into account how complementary and complex natures value relations are. This proposal of valuing integrally ecosystem goods and services contributes to adjusting political decisions more accordingly to real environmental conditions.
[en] The search for alternative energy production and consumption require a look into the industry of biofuels such as bioethanol as an alternative energy to overcome the disadvantages generated by the traditional methods of production and consumption, especially in the political, environmental and social issues and generate competitive advantages compared to other primary energy sources. In the present document, and from the Michael Porter five (5) Forces model is detailed an evaluation of the bioethanol industry as an alternative fuel and is described how attractive or competitive may become the industry today. To achieve this purpose, an evaluation of the competitive forces was proposed to a group of experts, using a Likert scale. Thus, it was evaluated the potential usefulness of the proposal.
[en] The population growth and the urban concentration involve a sustained increment in water demand, which requires an adequate effort and management of the ecosystems that provide the liquid to guarantee a plenty future offer. The performance of the entities in charge of the management of such ecosystems and the results obtained in the basins that supply drinkable water to two cities in Colombia are analyzed; financial topics and their relation with the local community are considered. Management is delegated to governmental entities, whose work is insufficient and unsatisfactory. Thus, application of economical, legal and social tools is proposed in order to improve ecosystem's conservation and life quality of farmers that inhabit in their influence areas, partially transferring management to the local community's orbit.
[en] 1,1,1-trichloro-2,2 bis (p-chlorophenyl) ethane (DDT) has been used since the Second World War to control insect-borne diseases in humans and domestic animals. The use of these organochlorine insecticides has been banned in most countries because of its persistence in the environment, biomagnification and potential susceptibility to toxicity to higher animals. Bioremediation involves the use of microorganisms to degrade organic contaminants in the environment, transforming them into simpler and less dangerous, even harmless compounds. This decontamination strategy has low costs, and wide public acceptance, also it can take place on the site. Compared to other methods, bioremediation is a more promising and less expensive to eliminate contaminants in soil and water. In soil, compounds such as DDT, chlorinated biphenyls can be partially biodegraded by a group of aerobic bacteria that cometabolize the contaminant. The bioavailability of pollutants may be enhanced by treating the soil in the presence of contaminant mobilizing agents such as surfactants. In this review we discuss the different strategies for bioremediation of soil contaminated with DDT, including mechanisms and degradation pathways. The application of these techniques in contaminated soil is also described. This review also discusses which is the best strategy for bioremediation of DDT.
[en] The rate of decomposition of leaf litter of four native species and three exotic species were evaluated. They were selected due to the most frequently collected by the bank vegetation Gaira river, located on the sierra Nevada de Santa Marta. We took four sampling sections at different heights. Furthermore, it was evaluated the richness, abundance and trophic function of macroinvertebrates that colonized the artificial substrates containing leaf packs or meshes. The middle part had the greatest rate of decomposition of native and exotic species (kw = 15.9, n = 23, p = 0.001 and kw = 15.5, n = 36, p = 0.0014 respectively). The native species had the highest rates (kw = 4, n = 47, p = 0.04), with the species pithecellobium longifolium in the middle stretch, which had the greatest mass loss over time. Descriptively a relationship between decomposition rate and current velocity is presented. the macroinvertebrate assemblage was represented by 41 taxa, with an abundance of 1895 individuals which provided a biomass of 2.27 g. the functional structure of macroinvertebrates associated with leaf litter was represented in the upper, middle and low reaches by plecoptera (predators) of the genus anacroneuria with 10.14%, 68.43% and 7.60% respectively. The taxon tanypodinae (diptera) predators were dominant in the mouth with 0.51%. The result of this study can determinate whether the presence of macroinvertebrates associated with leaf litter, is not conditioned by the plant species (native or exotic), and not enter these differences that create an effect on the rate of decomposition.
[en] In different areas near Velez (Santander) as La Paz, Chipata, Bolivar and Guavata it was identified a stratum with variable thickness, biostratonomy and characteristic fossil association. This bed had already been recognized in the Villa de Leyva (Boyaca) area, and located to the lower Barremian into the lowest multicolor mudstones level strata of the Paja Formation. The chaotic accumulation of molluscs fragments, complete ammonites, trunks and foraminifera is its principal characteristic, which makes its easy recognition in the field. To Villa de Leyva was possible to identify into the bed Crioceratites sp., Acrioceras julivertii Etayo-Serna, Pseudohaploceras incertum (Riedel), Nicklesia pulchella (D'Orbigny), Acanthoptychoceras trumpyi Kakabadze and Thieuloy, Phylloceras sp., Buergliceras buerglii Etayo-Serna, Valdedorsella sp. y Karsteniceras beyrichi (Karsten). To Velez area Pedioceras sp., Nicklesia pulchella (D'Orbigny), Acanthoptychoceras trumpyi Kakabadze and Thieuloy, Buergliceras buerglii (Etayo-Serna) y Pseudohaploceras incertum (Riedel). The ammonite association indicates the Nicklesia pulchella biozone of the Colombian early Barremian. The recognition of this level with a high-energy accumulation to the areas of Villa de Leyva and Velez can be indicating a regional distribution of a sedimentary event with these characteristics to the lower part of the Barremian from Colombia, which could be setting a sequence boundary to the basis of a high-energy transgressive system.
[en] Five species of army ants (Labidus coecus, Labidus coecus, Neivamyrmex punctaticeps, Cheliomyrmex andicola y Eciton dulcium) are recorded from land under seven different use regimes in Caqueta Department. The ants were captured in agricultural areas of the Amazonian foothills using four sampling methods (TSBF, screening of litter, formalin soil wash, and direct search). We provide information about distribution and habits for each species and report the presence of C. andicola and E. dulcium in Caqueta for the first time. These records contribute to a better knowledge of the ant fauna in Colombia.
[en] Proteins containing a TIR domain (toll interleukin receptor) are involved in plant and animal immunity. The aim of this work was to carry out an overall genomic analysis of cassava proteins with a TIR domain and discern their possible role in resistance to cassava bacterial blight. In total 46 proteins with a TIR domain were identified in the cassava proteome and were classed in four categories according the presence or absence of other domains: TIR (T), TIR -NB (TN), TIR - lRR (TL) and TIR - NB - lRR (TNL). 56.6 % of these 46 proteins have TIR, NB and lRR domains. Using multiple alignments it was possible to demonstrate that not all cassava TIR domains contain the AE region, involved in dimerization and activation of immune responses. Three of the four proteins categories (T, TNL and TN) presented a higher number of synonymous substitutions suggesting that they are not involved in recognition process. two TIR domains not presenting the ae region were analyzed by yeast two hybrid assays and by agro-infiltration, finding that both are able to form homo and heterodimers, but they do not trigger defense responses. With this study it was possible to conclude that TIR domains can function as adaptors in the signal transduction with other resistance proteins. In addition, it became clear that not always the AE region is important for TIR dimerization but it seems necessary to activate defense responses signals.