Espinoza T.E.B.,National University San Antonio Abad del Cusco
Novon | Year: 2014
Two new species were found during a taxonomic revision of Passiflora subg. Decaloba (DC.) Rchb. (Passifloraceae). Both new species are described and placed in the P. lobbii Mast. species group. Passiflora joergenseniana T. Boza is from La Paz, Bolivia, and P. praemorsa T. Boza is from Cusco, Peru, and is also distributed in La Paz, Bolivia. Conservation assessments and geographic distributions for each species are provided, and morphological variability within each species is discussed. Similarities to and differences among these new species and putative close relatives are also examined.
Ferrer I.,University of Barcelona |
Garfi M.,University of Barcelona |
Uggetti E.,University of Barcelona |
Ferrer-Marti L.,University of Barcelona |
And 2 more authors.
Biomass and Bioenergy | Year: 2011
Low-cost tubular digesters originally developed in tropical regions have been adapted to the extreme weather conditions of the Andean Plateau (3000-4000 m.a.s.l.). The aim of this study was to characterise biogas production in household digesters located at high altitude, operating under psychrophilic conditions. To this end, two pilot digesters were monitored and field campaigns were carried out in two representative digesters of rural communities. Digesters' useful volume ranged between 2.4 and 7.5 m 3, and hydraulic residence time (HRT) between 60 and 90 days. The temperature inside the digester's greenhouse ranged between 20 and 25 °C. Treating cow manure, a specific biogas production around 0.35 m 3 kg VS -1 was obtained, with some 65% CH 4 in biogas. In order to fulfil daily requirements for cooking and lighting, biogas production should be enhanced without increasing implementation costs as not to impede the expansion of this technology at household scale. In this sense, HRT below 60 days and OLR above 1 kg VS m -3 day -1 should be investigated to decrease digesters' volume (i.e. costs) and increase biogas production rate. The adaptation of conventional gas burners to biogas characteristics can also contribute in improving the efficiency of the system. © 2011 Elsevier Ltd.
Zimmermann M.,James Cook University |
Zimmermann M.,University of Edinburgh |
Meir P.,University of Edinburgh |
Bird M.I.,James Cook University |
And 2 more authors.
Global Biogeochemical Cycles | Year: 2010
To simulate the effect of temperature on soil respiration rates, we translocated soil cores among four sites (3030, 1500, 1000, and 200 m asl) along an altitudinal tropical forest gradient in the Peruvian Andes, traversing a difference in mean annual temperature of 13.9C. Rates of total (Rs) and heterotrophic (Rsh) respiration were measured twice a month from April 2007 to March 2009 and additionally for full 24 h periods. The diurnal range in Rs increased with altitude; this variation was mainly root and litter derived, whereas Rsh varied only slightly over full 24 h periods. Although mean annual daytime Rs rates were not significantly different among the four sites (4.45-4.05 mol CO2 m-2 s-1), the annual amount of respired C decreased with increasing altitude from 1639 g C m-2 yr-1 at 200 m asl to 1064 g C m-2 yr-1 at 3030 m asl. The contribution of Rsh to Rs was not correlated with elevation and ranged from 25% to 60%. The temperature dependence of Rs was lower at the midelevation sites (Q10 of 2.07 and 2.94 at 1500 and 1000 m asl, respectively) than at the highest and lowest sites of the gradient (Q10 of 4.33 and 6.92 at 3030 and 200 m asl, respectively). The temperature sensitivity of R sh was higher for the sites at 3030 and 200 m asl and increased with time, i.e., with the loss of the most labile C pools. © 2010 by the American Geophysical Union.
Youngsteadt E.,North Carolina State University |
Bustios P.G.,National University San Antonio Abad del Cusco |
Bustios P.G.,University of Concepción |
Schal C.,North Carolina State University
PLoS ONE | Year: 2010
In lowland Amazonian rainforests, specific ants collect seeds of several plant species and cultivate them in arboreal carton nests, forming species-specific symbioses called ant-gardens (AGs). In this obligate mutualism, ants depend on the plants for nest stability and the plants depend on ant nests for substrate and nutrients. AG ants and plants are abundant, dominant members of lowland Amazonian ecosystems, but the cues ants use to recognize the seeds are poorly understood. To address the chemical basis of the ant-seed interaction, we surveyed seed chemistry in nine AG species and eight non-AG congeners. We detected seven phenolic and terpenoid volatiles common to seeds of all or most of the AG species, but a blend of the shared compounds was not attractive to the AG ant Camponotus femoratus. We also analyzed seeds of three AG species (Anthurium gracile, Codonanthe uleana, and Peperomia macrostachya) using behavior-guided fractionation. At least one chromatographic fraction of each seed extract elicited retrieval behavior in C. femoratus, but the active fractions of the three plant species differed in polarity and chemical composition, indicating that shared compounds alone did not explain seed-carrying behavior. We suggest that the various AG seed species must elicit seed-carrying with different chemical cues. © 2010 Youngsteadt et al.
Chuquimaco I.H.,National University San Antonio Abad del Cusco
Phytotaxa | Year: 2016
The name Vochysia moskovitsiana Huamantupa (2012: 142) was not validly published due to errors in the citation of the holotype. In the type paragraph following the name citation, a single gathering but more than one specimen, E. Gudiño 1190 (QCNE, MO) was cited as the type. This is a defective citation according to the International Code for Nomenclature (ICN) Article 40.7 (McNeill et al. 2012) because a single specimen is not indicated as the holotype. Although a separate collection, Gudiño and Gualinga 1622 (MO), is cited in the caption to Figure 2 as the holotype, the same specimen also appears in the list of paratypes on page 147. Thus the citation of type is entirely ambiguous, and this work does not constitute valid publication. © 2016 Magnolia Press.
Salazar H.,University of Texas Medical Branch |
Swanson J.,University of Texas Medical Branch |
Mozo K.,National University San Antonio Abad del Cusco |
Clinton White Jr. A.,University of Texas Medical Branch |
Cabada M.M.,University of Texas Medical Branch
Journal of Travel Medicine | Year: 2012
Background Increasing numbers of travelers are visiting high altitude locations in the Andes. The epidemiology of acute mountain sickness (AMS) among tourists to high altitude in South America is not well understood. Methods A cross-sectional study to evaluate the epidemiology, pre-travel preparation, and impact of AMS among travelers to Cusco, Peru (3,400 m) was performed at Cusco's International Airport during June 2010. Foreign travelers, 18 years or older, staying 15 days or less, departing Cusco were invited to participate. Demographic, itinerary, and behavioral data were collected. The Lake Louise Clinical score (LLCS) was used to assess AMS symptoms. Results In total, 991 travelers participated, median age 32 years (interquartile range 25-49), 55.5% female, 86.7% tourists, mostly from the United States (48.2%) and England (8.1%). Most (76.7%) flew from sea level to Cusco and 30.5% visited high altitude in the previous 2 months. Only 29.1% received AMS advice from a physician, 19% recalled advice on acetazolamide. Coca leaf products (62.8%) were used more often than acetazolamide (16.6%) for prevention. AMS was reported by 48.5% and 17.1% had severe AMS. One in five travelers with AMS altered their travel plans. Travelers older than 60 years, with recent high altitude exposure, who visited lower cities in their itinerary, or used acetazolamide were less likely to have AMS. Using coca leaf products was associated with increased AMS frequency. Conclusions AMS was common and adversely impacted plans of one in five travelers. Acetazolamide was associated with decreased AMS but was prescribed infrequently. Other preventive measures were not associated with a decrease in AMS in this population. Pre-travel preparation was suboptimal. © 2012 International Society of Travel Medicine.
Sylvester S.P.,National University San Antonio Abad del Cusco |
Sylvester M.D.P.V.,National University San Antonio Abad del Cusco |
Kessler M.,University of Zürich
Journal of Vegetation Science | Year: 2014
Questions: Have millennia of human land use fundamentally altered the vegetation of a large proportion of the high Andean puna biome, with natural vegetation now restricted to inaccessible areas? Can inaccessible ledges be used as surrogates to infer the potential natural vegetation (PNV) in heavily impacted areas of the puna ecosystem of the high Andes? Is there a difference in plant community composition and diversity between the potential natural puna vegetation, represented by areas inaccessible to grazing and burning, and the anthropogenically disturbed vegetation found on nearby, but accessible, slopes? Location: Abra Málaga Private Conservation Area, Cusco, southern Peruvian Andes. Methods: Four study habitats were chosen that comprised ledges and slopes from within and outside of the conservation area. For each habitat, vegetation composition was recorded using eight to twelve 2 × 2-m2 plots studied for species cover and abiotic variables. Results: Analysis of species richness using two-way ANOVAs with Tukey test found that plots from the three habitats inaccessible to anthropogenic disturbance exhibited similar richness levels, whereas plots accessible to grazing and anthropogenic burning had significantly higher species richness. Likewise, CCA separated out plots of the three habitats inaccessible to anthropogenic disturbance from the unconserved slope plots. Species indicator analyses found the three inaccessible habitats to share the largest number of indicator species, with none being shared by the accessible, unconserved slope habitat. The PNV, inferred from the inaccessible vegetation, comprises a mosaic of Polylepis pepei woodland and tussock grassland, dominated by Festuca aff. procera, Luzula gigantea, Valeriana mandoniana and Carex pichinchensis. Conclusions: As both the conserved and unconserved ledge habitats contain a vegetation that approaches that of the conserved slope, ledges can be taken as a surrogate to infer the PNV in heavily impacted areas where no conserved slopes are available. From preliminary data, the presumed PNV of the study area corresponds to a distinct vegetation assemblage including species previously unknown to science. Adjacent disturbed, accessible land contained a higher species diversity, with a flora that may have originated from localized, disturbed natural habitats. © 2014 International Association for Vegetation Science.
Robertson A.L.,University of Alaska Fairbanks |
Malhi Y.,University of Oxford |
Farfan-Amezquita F.,National University San Antonio Abad del Cusco |
Aragao L.E.O.C.,University of Oxford |
And 2 more authors.
Global Change Biology | Year: 2010
Autotrophic respiration involves the use of fixed carbon by plants for their own metabolism, resulting in the release of carbon dioxide as a by-product. Little is known of how autotrophic respiration components vary across environmental gradients, particularly in tropical ecosystems. Here, we present stem CO2 efflux data measured across an elevation transect spanning ca. 2800m in the Peruvian Amazon and Andes. Forest plots from five elevations were studied: 194, 210, 1000, 1500, and 3025masl Stem CO2 efflux (Rs) values from each plot were extrapolated to the 1-ha plot level. Mean Rs per unit stem surface area declined significantly with elevation, from 1.14±0.12 at 210m elevation to 0.62±0.09μmolCm-2s-1 at 3025m elevation. When adjusted for changing forest structure with elevation, this is equivalent to 6.45±1.12MgCha-1yr-1 at 210m elevation to 2.94±0.19MgCha-1yr-1 at 3025m elevation. We attempted to partition stem respiration into growth and maintenance respiration components for each site. Both growth and maintenance respiration rates per unit stem showed similar, moderately significant absolute declines with elevation, but the proportional decline in growth respiration rates was much greater. Stem area index (SAI) showed little trend along the transect, with declining tree stature at higher elevations being offset by an increased number of small trees. This trend in SAI is sensitive to changes in forest stature or size structure. In the context of rapid regional warming over the 21st century, such indirect, ecosystem-level temperature responses are likely to be as important as the direct effects of temperature on maintenance respiration rates. © 2010 Blackwell Publishing Ltd.
van de Weg M.J.,University of Edinburgh |
van de Weg M.J.,The Ecosystem Center |
Meir P.,University of Edinburgh |
Grace J.,University of Edinburgh |
Ramos G.D.,National University San Antonio Abad del Cusco
Oecologia | Year: 2012
Few data are available describing the photosynthetic parameters of the leaves of tropical montane cloud forests (TMCF). Here, we present a study of photosynthetic leaf traits (V cmax and J max), foliar dark respiration (R d), foliar nitrogen (N) and phosphorus (P), and leaf mass per area (LMA) throughout the canopy for five different TMCF species at 3025 m a. s. l. in Andean Peru. All leaf traits showed a significant relationship with canopy height when expressed on an area basis, and V cmax-area and J max-area almost halved when descending through the TMCF canopy. When corrected to a common temperature, average V cmax and J max on a leaf area basis were similar to lowland tropical values, but lower when expressed on a mass basis, because of the higher TMCF LMA values. By contrast, R d on an area basis was higher than found in tropical lowland forests at a common temperature, and similar to lowland forests on a mass basis. The TMCF J max-V cmax relationship was steeper than in other tropical biomes, and we propose that this can be explained by either the light conditions or the relatively low VPD in the studied TMCF. Furthermore, V cmax had a significant-though relatively weak and shallow-relationship with N on an area basis, but not with P, which is consistent with the general hypothesis that TMCFs are N rather than P limited. Finally, the observed V cmax-N relationship (i.e., maximum photosynthetic nitrogen use efficiency) was distinctly different from those in tropical and temperate regions, probably because the TMCF leaves compensate for reduced Rubisco activity in cool environments. © 2011 Springer-Verlag.
Rapp J.M.,Wake forest University |
Rapp J.M.,Harvard University |
Silman M.R.,Wake forest University |
Clark J.S.,Duke University |
And 3 more authors.
Ecology | Year: 2012
Tree growth response across environmental gradients is fundamental to understanding species distributional ecology and forest ecosystem ecology and to predict future ecosystem services. Cross-sectional patterns of ecosystem properties with respect to climatic gradients are often used to predict ecosystem responses to global change. Across sites in the tropics, primary productivity increases with temperature, suggesting that forest ecosystems will become more productive as temperature rises. However, this trend is confounded with a shift in species composition and so may not reflect the response of in situ forests to warming. In this study, we simultaneously studied tree diameter growth across the altitudinal ranges of species within a single genus across a geographically compact temperature gradient, to separate the direct effect of temperature on tree growth from that of species compositional turnover. Using a Bayesian state space modeling framework we combined data from repeated diameter censuses and dendrometer measurements from across a 1700-m altitudinal gradient collected over six years on over 2400 trees in Weinmannia, a dominant and widespread genus of cloud forest trees in the Andes. Within species, growth showed no consistent trend with altitude, but higher-elevation species had lower growth rates than lowerelevation species, suggesting that species turnover is largely responsible for the positive correlation between productivity and temperature in tropical forests. Our results may indicate a significant difference in how low- and high-latitude forests will respond to climate change, since temperate and boreal tree species are consistently observed to have a positive relationship between growth and temperature. If our results hold for other tropical species, a positive response in ecosystem productivity to increasing temperatures in the Andes will depend on the altitudinal migration of tree species. The rapid pace of climate change, and slow observed rates of migration, suggest a slow, or even initially negative response of ecosystem productivity to warming. Finally, this study shows how the observed scale of biological organization can affect conclusions drawn from studies of ecological phenomena across environmental gradients, and calls into question the common practice in tropical ecology of lumping species at higher taxonomic levels. © 2012 by the Ecological Society of America.