Browsing by Author

  • Publication
    Crescendo, diminuendo and subito of the trumpets: winds of change in the concerted evolution between flowers and pollinators in Salpichroa (Solanaceae)
    (Academic Press Inc., 2019)
    Ibañez A.C.
    ;
    Moré M.
    ;
    SALAZAR HINOSTROZA, JESUS MANUEL
    ;
    LEIVA TAFUR, DAMARIS
    ;
    BARBOZA CASTILLO, ELGAR
    ;
    Cocucci A.A.
    ‘Gradual’ vs ‘punctuated’ and ‘unidirectional’ (only lengthening) vs. ‘bidirectional’ (lengthenings and shortenings) modes of evolution are explanations that compete to explain adaptive changes of flower tube length in angiosperm. The nightshade genus Salpichroa Miers, with 21 species mostly growing in the tropical Andes of southern South America, has the opportune qualities of including nearly 15-fold inter-specific variation in corolla tube length, as well as one species that is a candidate for participating in evolutionary escalation with the longest-billed hummingbird, Ensifera ensifera. We reconstructed the phylogenetic relationships using five molecular markers, the two plastid markers trnD-trnT and trnL, and three nuclear markers, ITS and two COSII, and estimated divergence times of the genus in order to reconstruct the history of both corolla tube length and pollination mode (i.e. hummingbirds, moths or multiple). We used comparative methods to determine whether corolla tube elongation/shortening is associated with shifts in pollination mode and to test, modes and rates of corolla tube change. We found evidence of both lengthening and shortening of corolla tubes. Evolutionary rates are consistent with rapid corolla tube length transitions that are only partly associated with shifts in pollination mode. Though ‘punctuated’ evolution (i.e. large changes predominantly at speciation events) explained corolla changes in the whole genus, ‘gradual’ evolution (i.e. gradual changes during a coevolutionary race with the same pollinator) was a better explanation for the change in the long-flowered clade, mostly pollinated by hummingbirds. © 2018 Elsevier Inc.
    Scopus© Citations 3
  • Publication
    Morphometric prioritization, fluvial classification, and hydrogeomorphological quality in high Andean livestock micro-watersheds in northern Peru
    (MDPI AG, 2020-05-01)
    ROJAS BRICEÑO, NILTON BELTRÁN
    ;
    Oliva M.
    ;
    BARBOZA CASTILLO, ELGAR
    ;
    GAMARRA TORRES, OSCAR ANDRES
    ;
    LEIVA TAFUR, DAMARIS
    ;
    BARRENA GURBILLON, MIGUEL ANGEL
    ;
    Corroto F.
    ;
    SALAS LOPEZ, ROLANDO
    ;
    RASCÓN BARRIOS, JESÚS
    Anthropic activity affects the hydrogeomorphological quality of fluvial systems. River and valley classifications are fundamental preliminary steps in determining their ecological status, and their prioritization is essential for the proper planning and management of soil and water resources. Given the importance of the High Andean livestock micro-watershed (HAL-MWs) ecosystems in Peru, an integrated methodological framework is presented for morphometric prioritization that uses a Principal Component Analysis (PCA) and Weighted Sum Approach (WSA), geomorphological fluvial classifications (channel, slope, and valley), and hydrogeomorphological evaluations using the Hydrogeomorphological Index (IHG). Of six HALMWs studied in Leimebamba and Molinopampa (Amazonas region), the PCWSA hybrid model identified the San Antonio HAL-MW as a top priority, needing the rapid adoption of appropriate conservation practices. Thirty-nine types of river course were identified, by combining 13 types of valley and 11 types of riverbed. The total assessment of the IHG indicated that 7.6% (21.8 km), 14.5% (41.6 km), 27.9% (80.0 km), and 50.0% (143.2 km) of the basin lengths have "Poor", "Moderate", "Good", and "Very good" quality rankings, respectively. The increase in the artificial use of river channels and flood plains is closely linked to the decrease in hydrogeomorphological quality.
  • Publication
    Spatial and temporal dynamics of the trophic state in a tropical high Andean lake in northern
    (Asociacion Argentina de Ecologia, 2021-08-01)
    RASCÓN BARRIOS, JESÚS
    ;
    Corroto F.
    ;
    LEIVA TAFUR, DAMARIS
    ;
    GAMARRA TORRES, OSCAR ANDRES
    Perú. Lake Pomacochas is located in the montane forest region of northern Perú, in an area of great agricultural and fish farming importance, activities that represent the basis of the local economy. The population settled on its margins discharges part of its wastewater into the lake without treatment. The main aim of this study was to determine the spatio-temporal dynamics of this lentic ecosystem, evaluating the limnological and trophic conditions during the dry and rainy periods, and their relationship with each other. The following limnological variables were analyzed at 15 sampling sites: Transparency, chlorophyll ‘a’, temperature, pH, conductivity, oxygen saturation, turbidity, nitrates, nitrites, ammonium and soluble reactive phosphorus. Besides, the following trophic indices were calculated: Carlson’s trophic status index (TSIC), trophic status index modified by Aizaki et al. (TSIA), trophic status index modified by Toledo et al. (TSIT) and trophic status index by Vollenweider et al. (TRIX). The lake showed temporal, but not spatial, variation for both limnological variables and trophic indices. The dynamics of the limnological variables in the different climatic periods was also analyzed. The TSIC and TSIA indexes indicated that the lake can be characterized as α-mesotrophic to β-eutrophic, and according to TSIT index as α-mesotrophic to α-eutrophic. The TRIX showed the system has a poor water quality, highly productive, and a very high trophic level. The results reveal that the TSIA best described the trophic state of the lake, while the TSIC was the worst. All these results were statistically significant (P<0.05). The trophic indices evidenced that lake Pomacochas shows a strong tendency to the eutrophication due to agricultural activities. The study also showed that the system is conditioned by climatic seasonality.
  • Publication
    Unraveling the phylogenetic relationships of Nectouxia (Solanaceae): its position relative to Salpichroa
    (Springer-Verlag Wien, 2018)
    Carrizo García C.
    ;
    Basso A.V.
    ;
    LEIVA TAFUR, DAMARIS
    ;
    Gonzáles P.
    ;
    BARBOZA CASTILLO, ELGAR
    Nectouxia (Solanaceae) is a monospecific genus endemic to Mexico and southern United States of America. Morphological and phylogenetic evidence supports a close relationship between Nectouxia and the Andean genus Salpichroa, but the phylogenetic analyses completed to date have included very few Salpichroa species. A comprehensive phylogenetic analysis including Nectouxia and all Salpichroa species was carried out to shed light on the relationship between the two genera. Maximum parsimony and Bayesian inference analyses were done using sequences from three markers (ITS, psbA-trnH, and ndhF-rpL32). The results of both analyses are congruent regarding the strongly supported clades while incongruences are observed in weakly supported clades that can be explained by rapid species radiation. Salpichroa species are divided in two main clades with strong support, while Nectouxia is resolved within one of them. Our results indicate that the two genera should be combined into a single genus or Salpichroa will be paraphyletic as currently circumscribed. The name Nectouxia has priority but the conservation of Salpichroa has been proposed. At the suprageneric level, the Nectouxia + Salpichroa clade is not closely related to Jaborosa, which is further evidence that the previously recognized tribe Jaboroseae is not monophyletic. © 2017, Springer-Verlag GmbH Austria.
    Scopus© Citations 4