Spatial and Temporal Dynamics of the Vegetation Cover from the Bijagual Massif, Boyacá, Colombia, during the 1986-2021 Period.

Landscape changes based on spectral responses allow showing plant cover changes through diversity, composition, and ecological connectivity. The spatial and temporal vegetation dynamics of the Bijagual Massif from 1986 to 2021 were analyzed as a measure of ecological integrity, conservation, and territory. The covers identified were high open forest (Hof), dense grassland of non-wooded mainland (Dgnm), a mosaic of pastures and crops (Mpc), lagoons (Lag), and bare and degraded lands (Bdl). The Bijagual Massif has 8574.1 ha. In 1986, Dgnm occupied 42.6% of the total area, followed by Mpc (32.8%) and Hof (24.5%); by 2000, Mpc and Hof increased (43.7 and 28.1%, respectively), while Dgnm decreased (28%); by 2021, Dgnm was restricted to the northeastern zone and continued to decrease (25.2%), Mpc occupied 52.9%, Hof 21.7% and Bdl 0.1%. Of the three fractions of the connectivity probability index, only dPCintra and dPCflux contribute to ecological connectivity. Hof and Dgnm show patches with biota habitat quality and availability. Between 1986 and 2021, Dgnm lost 1489 ha (41%) and Hof 239.5 ha (11%). Mpc replaced various covers (1722.2 ha; 38%) in 2021. Bijagual has a valuable biodiversity potential limited by Mpc. Territorial planning and sustainable agroecological and ecotourism proposals are required due to the context of the ecosystems.

Mycorrhizal symbioses in the Andean paramo.

The Andean paramo, hereafter "paramo", is a Neotropical high-mountain region between the treeline and permanent snowline (3500-4800 m) and is considered the world's coolest biodiversity hotspot. Because of paramo's high humidity, solar radiation and temperature variation, mycorrhizal symbiosis is expected to be essential for plants. Existing theory suggests that replacement of arbuscular mycorrhizal (AM) by ectomycorrhizal (ECM) and then ericoid mycorrhizal plants (ERM) can be expected with increasing elevation. Previous findings also suggest that non-(NM) and facultatively mycorrhizal (FM) species predominate over obligatory mycorrhizal (OM) species at high elevations. However, these expectations have never been tested outside of the northern temperate zone. We addressed the distribution and environmental drivers of plant mycorrhizal types (AM, ECM and ERM) and statuses (NM, FM and OM) along the paramo's elevational gradient. We used vegetation plots from the VegParamo database, climatic and edaphic data from online repositories, and up-to-date observation information about plant mycorrhizal traits at species and genus level, the latter being proposed as hypotheses. AM plants were dominant along the entire gradient, and ERM plants were most abundant at the lowest elevations (2500-3000 m). The share of FM plants increased and that of OM plants decreased with elevation, while NM plants increased above 4000 m. Temperature and soil pH were positively related to the abundance of AM plants and negatively to ERM plants. Our results reveal patterns that contrast with those observed in temperate northern-hemisphere ecosystems.

Brief windows with more favorable atmospheric conditions explain patterns of Polylepis reticulata tree water use in a high-altitude Andean forest.

Polylepis trees occur throughout the Andean mountain region, and it is the tree genus that grows at the highest elevation worldwide. In the humid Andes where moisture is rarely limiting, Polylepis trees must adapt to extreme environmental conditions, especially rapid fluctuations in temperature, ultraviolet radiation and vapor pressure deficit (VPD). However, Polylepis' water-use patterns remain largely unknown despite the importance of understanding their response to microclimate variation to determine their capacity to maintain resilience under future environmental change. We conducted a study in a Polylepis reticulata Kunth forest in the Ecuadorian Andes to evaluate its tree water-use dynamics and to identify the main environmental drivers of transpiration. Tree sap flow was monitored simultaneously with soil volumetric water content (VWC) and microclimate during 2 years for trees growing in forest edge and interior locations. We found that sap flow was primarily controlled by VPD and that VWC exerted a secondary role in driving sap flow dynamics. The highest values for sap flow rates were found when VPD > 0.15 kPa and VCW < 0.73 cm3 cm-3, but these threshold conditions only occurred during brief periods of time and were only found in 11% of our measurements. Moreover, these brief windows of more favorable conditions occurred more frequently in forest edge compared with forest interior locations, resulting in edge trees maintaining 46% higher sap flow compared with interior trees. Our results also suggest that P. reticulata has a low stomatal control of transpiration, as the sap flow did not decline with increasing VPD. This research provides valuable information about the potential impacts of projected future increases in VPD due to climate change on P. reticulata water-use dynamics, which include higher sap flow rates leading to greater transpirational water loss due to this species' poor stomatal control.

Allopatric speciation is more prevalent than parapatric ecological divergence in a recent high-Andean diversification (Linochilus: Asteraceae).

Elucidating how species accumulate in diversity hotspots is an ongoing debate in evolutionary biology. The páramo, in the Northern Andes, has remarkably high indices of plant diversity, endemicity, and diversification rates. A hypothesis for explaining such indices is that allopatric speciation is high in the páramo given its island-like distribution. An alternative hypothesis is that the altitudinal gradient of the Andean topography provides a variety of niches that drive vertical parapatric ecological speciation. A formal test for evaluating the relative roles of allopatric and parapatric ecological speciation is lacking. The main aim of our study is to test which kind of speciation is more common in an endemic páramo genus. We developed a framework incorporating phylogenetics, species' distributions, and a morpho-ecological trait (leaf area) to compare sister species and infer whether allopatric or parapatric ecological divergence caused their speciation. We applied our framework to the species-rich genus Linochilus (63 spp.) and found that the majority of recent speciation events in it (12 events, 80%) have been driven by allopatric speciation, while a smaller fraction (one event, 6.7%) is attributed to parapatric ecological speciation; two pairs of sister species produced inconclusive results (13.3%). We conclude that páramo autochthonous (in-situ) diversification has been primarily driven by allopatric speciation.

Eastern Colombian Páramo Liodessus Guignot, 1939 diving beetles are genetically structured, but show signs of hybridization, with description of new species and subspecies (Coleoptera, Dytiscidae).

We studied Liodessus diving beetles from six eastern Colombian Páramo areas, as well as from the Altiplano. We discovered a highly characteristic new species, based on male genital morphology, Liodessussantarositasp. nov., in the Páramo de Guantiva-Rusia. Specimens from the Altiplano around Bogotá, and the Páramos of Almorzadero, Chingaza, Matarredonda, Rabanal y Rio Bogotá and Sumapaz form one clade of genetically similar populations based on mitochondrial Cox1 sequence data. The individuals of this clade are sub-structured according to their geographic distribution. The populations differ from each other mainly in terms of body size and coloration and, at most, subtly in their genital morphology. In two cases, we find putative hybrid populations between Altiplano and Páramo areas. We suggest that the different Páramo populations are in an early phase of speciation, and perhaps already genetically isolated in some cases. They are here assigned subspecies status to highlight these ongoing processes pending more comprehensive geographic sampling and use of genomic data. We refer to this clade as the Liodessusbogotensis complex, containing Liodessusb.bogotensis Guignot, 1953; Liodessusb.almorzaderossp. nov.; Liodessusb.chingazassp. nov.; Liodessusb.lacunaviridis Balke et al., 2021, stat. nov.; Liodessusb.matarredondassp. nov., and Liodessusb.sumapazssp. nov.

Vegetation structure and aboveground biomass of Páramo peatlands along a high-elevation gradient in the northern Ecuadorian Andes.

The high-elevation peatlands of the páramos of the northern Andes constitute a diverse environment that harbors large numbers of species and several types of plant communities along altitudinal, latitudinal, and environmental gradients. However, little is known about the structure and functioning of these ecosystems, including peatland vegetation types and their relative contribution to the production and accumulation of peat soils. In this paper we characterized the structure of peatland plant communities of the humid páramos of northern Ecuador by describing the distribution of plant growth-forms and their aboveground biomass patterns. Along an elevation gradient of 640 m we sampled vegetation in 16 peatlands and aboveground biomass in four peatlands. Three distinct peatland vegetation types were identified: High elevation Cushion peatlands, dominated by Plantago rigida and Distichia muscoides, Sedge and rush peatlands dominated by Carex spp. and Juncus spp., and Herbaceous and shrubby peatlands, with a more heterogenous and structurally complex vegetation. In terms of aboveground biomass, we found an 8-fold reduction in the higher peatlands compared to the lower sites, suggesting that the steep elevational gradients characteristic of Andean environments might be crucial in structuring the physiognomy and composition of peatland vegetation, either through its effects on temperature and other environmental factors, or through its effects on the age and development of soils. Additional studies are needed to evaluate the potential effects of temperature, hydrology, micro-topography, geological setting, and land-use, which are likely to influence vegetation patters in these peatlands.

Blooming plant species diversity patterns in two adjacent Costa Rican highland ecosystems.

The Costa Rican Paramo is a unique ecosystem with high levels of endemism that is geographically isolated from the Andean Paramos. Paramo ecosystems occur above Montane Forests, below the permanent snow level, and their vegetation differs notably from that of adjacent Montane Forests. We compared the composition and beta diversity of blooming plant species using phenological data from functional plant groups (i.e., insect-visited, bird-visited and insect + bird-visited plants) between a Paramo and a Montane Forest site in Costa Rica and analyzed seasonal changes in blooming plant diversity between the rainy and dry seasons. Species richness was higher in the Montane Forest for all plant categories, except for insect-visited plants, which was higher in the Paramo. Beta diversity and blooming plant composition differed between both ecosystems and seasons. Differences in species richness and beta diversity between Paramo and the adjacent Montane Forest are likely the result of dispersal events that occurred during the last glacial period and subsequent isolation, as climate turned to tropical conditions after the Pleistocene, and to stressful abiotic conditions in the Paramo ecosystem that limit species establishment. Differences in blooming plant composition between both ecosystems and seasons are likely attributed to differential effects of climatic cues triggering the flowering events in each ecosystem, but phylogenetic conservatism cannot be discarded. Analyses of species composition and richness based on flowering phenology data are useful to evaluate potential floral resources for floral visitors (insects and birds) and how these resources change spatially and temporarily in endangered ecosystems such as the Paramo.

Two new species of Ribes (Grossulariaceae) from Peru

The genus Ribes (Grossulariaceae) has a center of diversity in the tropical Andes, especially in Peru. Several new species have been discovered in recent years and additional collections keep turning up material of undescribed species. In the present study we describe two additional new species, both from the wide-ranging species complex around Ribes andicola. Ribes lambayequensis comes from a known centre of diversity of the Andean plants, the Amotape-Huancabamba Zone, but represents the first species of the genus from Lambayeque. It differs most obviously from its geographical neighbor Ribes colandina by its two-coloured flowers in erect inflorescences (versus uniformly dark red flowers in pendulous racemes in R. colandina). The other new species is described from Apurímac and represents the first microendemic species of Ribes from this generally poorly explored region. It is a far southern outlier of the Ribes andicola group, which otherwise finds its southern range limit in the Department of La Libertad. Ribes apurimacensis differs from its closest allies in the Ribes andicola group by an exclusively glandular indument (no simple hairs) in combination with smaller leaves, a serrate leaf margin and dark red flowers.

El género Ribes (Grossulariaceae) tiene un centro de diversidad en los Andes tropicales, especialmente en el Perú. Un número de especies nuevas se describieron en los últimos años y nuevo material sigue agregando novedades taxonómicas. En el presente estudio se describen dos especies nuevas adicionales, ambas de un complejo con amplia distribución afín a Ribes andicola. Ribes lambayequensis proviene de un centro de diversidad botánica bien documentado, la denominada zona Amotape-Huancabamba, pero representa la primera especie del género en Lambayeque. Difiere claramente de su vecino geográfico Ribes colandina en sus flores bicoloras en inflorescencias erguidas (versus flores rojo marrón en inflorescencias péndulas en R. colandina). La otra especie nueva se describe de Apurímac y representa la primera especie microendémica de Ribes de esta región poco investigada. Es muy distante del resto de la distribución principal del grupo Ribes andicola, normalmente restringido a la zona al norte de La Libertad. Ribes apurimacensis difiere de sus aliados en el grupo Ribes andicola en hojas solamente glandulosas (no pubescentes) en combinación con hojas más pequeñas, márgenes de las hojas serradas (no crenadas) y flores marrón oscuro.

New relevant chorological and conservation data on Carex (Cyperaceae) and Hypericum (Hypericaceae) from Ecuador.

Background: Knowledge of Carex L. (true sedges) and Hypericum L. (St. John's wort) in the Neotropics is fragmentary. New information: As a result of a fieldwork campaign in Ecuador and revision of herbarium collections (K, QCA and QCNE), we present here relevant records of twelve Carex (Cyperaceae) and four Hypericum (Hypericaceae) species. Regarding Carex, we present the novel report for South America of C.aztecica, as well as the first Ecuadorian records for C.brehmeri, C.collumanthus, C.fecunda, C.melanocystis and C.punicola. The three later records have additional biogeographical significance, as they represent the new northern limit of these species. We also include observations for another five species included in the Ecuadorian Red List of Endemic Plants. As a result, the list of native Carex reported for Ecuador would now include 52 taxa. With regard to Hypericum, we include the new report of H.sprucei for the province of Bolívar, and the confirmation of the presence of three rare species (H.acostanum, H.matangense, H.prietoi) in their type localities, although with extremely low population sizes. We discuss their conservation status and implications.

Influencia del cambio de uso del suelo sobre las reservas de carbono orgánico en el Parque Natural Regional Cortadera, Boyacá (Colombia)

Los páramos almacenan grandes reservas de carbono orgánico en el suelo (COS), influenciados por las condiciones climáticas y biogeoquímicas, propias del ecosistema; sin embargo, su progresiva conversión hacia cultivos, ganadería o minería incide directamente en las reservas de COS. Con el fin de determinar el efecto que ejerce el cambio de uso de suelo sobre la variabilidad de las reservas de COS, se realizó un monitoreo de COS entre 2013, 2018 y 2020, en el Parque Natural Regional Cortadera. Se estudiaron parcelas permanentes de muestreo (PPM), ubicadas bajo tres diferentes usos del suelo: conservado, en recuperación e intervenido. Se analizaron muestras de carbono orgánico y densidad aparente, a dos profundidades (0-15 cm y 15-30 cm). Se encontró que la PPM en escenario conservado presentó los contenidos más altos de COS, con valores de 290,37; 199,22 y 257,5 tC ha-1, para cada uno de los años en estudio; seguido por la PPM en recuperación, que evidenció valores de COS 215,3 tC ha-1, en el 2020, en contraste con la PPM intervenida, que presentó contenidos mínimos de 15,50; 34,01 y 88,06 tC ha-1. Se observó que los mayores contenidos de COS se encuentran a la profundidad de 15 a 30 cm. Dichos aspectos, resaltan la importancia de avanzar en acciones enfocadas a la protección de ecosistemas estratégicos, considerando las constantes amenazas relacionadas con la transformación del paisaje y, con ello, la posibilidad de proveer funciones y servicios asociados a la captura de carbono y la regulación climática.

The paramos accumulate high stocks of soil organic carbon (SOC), influenced by the climatic and biogeochemical conditions of the ecosystem. However, their progressive conversion to crops, livestock, or mining has a direct impact on the SOC stocks. To determine the effect of land use change on the variability of SOC stocks, monitoring of SOC content was conducted between the years 2013, 2018, and 2020 in the Parque Natural Regional Cortadera. Permanent sampling plots (PPS) located under three different land uses were studied: conserved, recovering, and intervened. To do so, samples of soil organic carbon and bulk density at two depths were analyzed (0-15 cm and 15-30 cm). The conserved PPS showed the highest SOC contents, with maximum values of 290.37; 199.22, and 257.5 tC ha-1 for each of the years under study; follow by the recovery PPM that presented COS values of 215.3 tC ha-1 in 2020, in contrast to the intervened PSP that showed minimum contents of 15.50; 34.01 and 88.06 tC ha-1. Furthermore, the highest SOC contents were found at 15-30 cm depth. These factors emphasize the importance of carrying out actions focused on protecting strategic ecosystems such as paramos, taking into account the continuous threats related to the transformation of the landscape and, consequently, the possibility of providing ecosystem functions and services related to carbon capture and climate regulation.

Low availability of functional seed trait data from the tropics could negatively affect global macroecological studies, predictive models and plant conservation.

BACKGROUND: Plant seeds have many traits that influence ecological functions, ex situ conservation, restoration success and their sustainable use. Several seed traits are known to vary significantly between tropical and temperate regions. Here we present three additional traits for which existing data indicate differences between geographical zones. We discuss evidence for geographical bias in availability of data for these traits, as well as the negative consequences of this bias. SCOPE: We reviewed the literature on seed desiccation sensitivity studies that compare predictive models to experimental data and show how a lack of data on populations and species from tropical regions could reduce the predictive power of global models. In addition, we compiled existing data on relative embryo size and post-dispersal embryo growth and found that relative embryo size was significantly larger, and embryo growth limited, in tropical species. The available data showed strong biases towards non-tropical species and certain families, indicating that these biases need to be corrected to perform truly global analyses. Furthermore, we argue that the low number of seed germination studies on tropical high-mountain species makes it difficult to compare across geographical regions and predict the effects of climate change in these highly specialized tropical ecosystems. In particular, we show that seed traits of geographically restricted páramo species have been studied less than those of more widely distributed species, with most publications unavailable in English or in the peer-reviewed literature. CONCLUSIONS: The low availability of functional seed trait data from populations and species in the tropics can have negative consequences for macroecological studies, predictive models and their application to plant conservation. We propose that global analyses of seed traits with evidence for geographical variation prioritize generation of new data from tropical regions as well as multi-lingual searches of both the grey- and peer-reviewed literature in order to fill geographical and taxonomic gaps.

Photosynthetic Traits of Páramo Plants Subjected to Short-Term Warming in OTC Chambers.

Global warming and changes in land use are some of the main threats to high mountain species. Both can interact in ways not yet assessed. In this study, we evaluated the photosynthetic responses of six common páramo species within a warming experiment using open-top chambers (OTC) in conserved páramo areas with different land use histories. We did not find significant differences in the photochemical performance of the species as measured through Fv/Fm, ETR, and NPQ in response to passive warming, indicating that warmed plants are not stressed. However, NPQ values were higher in recovering areas, especially in the driest and warmest months. Leaf transpiration, stomatal conductance, and Ci were not affected by the OTC or the land use history. The photosynthetic capacity, maximum photosynthetic capacity, and carboxylation rate of RuBisCO increased in response to warming but only in the area with no anthropogenic intervention. These results suggest that species will respond differently to warming depending on the history of páramo use, and therefore not all páramo communities will respond equally to climate change. In disturbed sites with altered soil conditions, plants could have a lower breadth of physiological response to warming.

Improving the remote estimation of soil organic carbon in complex ecosystems with Sentinel-2 and GIS using Gaussian processes regression.

Background and aims: The quantitative retrieval of soil organic carbon (SOC) storage, particularly for soils with a large potential for carbon sequestration, is of global interest due to its link with the carbon cycle and the mitigation of climate change. However, complex ecosystems with good soil qualities for SOC storage are poorly studied. Methods: The interrelation between SOC and various vegetation remote sensing drivers is understood to demonstrate the link between the carbon stored in the vegetation layer and SOC of the top soil layers. Based on the mapping of SOC in two horizons (0-30 cm and 30-60 cm) we predict SOC with high accuracy in the complex and mountainous heterogeneous páramo system in Ecuador. A large SOC database (in weight % and in Mg/ha) of 493 and 494 SOC sampling data points from 0-30 cm and 30-60 cm soil profiles, respectively, were used to calibrate GPR models using Sentinel-2 and GIS predictors (i.e., Temperature, Elevation, Soil Taxonomy, Geological Unit, Slope Length and Steepness (LS Factor), Orientation and Precipitation). Results: In the 0-30 cm soil profile, the models achieved a R2 of 0.85 (SOC%) and a R2 of 0.79 (SOC Mg/ha). In the 30-60 cm soil profile, models achieved a R2 of 0.86 (SOC%), and a R2 of 0.79 (SOC Mg/ha). Conclusions: The used Sentinel-2 variables (FVC, CWC, LCC/Cab, band 5 (705 nm) and SeLI index) were able to improve the estimation accuracy between 3-21% compared to previous results of the same study area. CWC emerged as the most relevant biophysical variable for SOC prediction. Supplementary Information: The online version contains supplementary material available at 10.1007/s11104-022-05506-1.

Notes on Peruvian Ribes cuneifolium and Ribes ovalifolium (Grossulariaceae)

The genus Ribes (Grossulariaceae) is widespread across the northern hemisphere, but also species-rich in the tropical Andes. In the Peruvian Andes the genus is mostly found in at least seasonally moist cloud and scrub forests, subparamo habitats and hedges. However, some taxa are from more extreme habitats in semi-arid habitats of the western slope of the Andes (Andean scrub, Ribes ovalifolium) respectively high Andean puna and paramo habitats at elevations of up to 5100 m asl (Ribes cuneifolium and some doubtful segregates). These species share small, weakly divided leaves, making them quite atypical for the genus, usually with large, deeply threeto five-lobed leaves. Both the geographical ranges and the species delimitation for both taxa are poorly understood. We here propose the recognition of only two, well-differentiated species. Ribes ovalifolium can be shown to be wide-ranging from northern Ancash to Tacna, covering nearly the entire western flank of the Peruvian Andes. Similarly, Ribes cuneifolium can be shown to represent a single, wide-ranging species from high elevations of San Martín/La Libertad to Cuzco. There is considerable diversity on details of indument, flower color and leaf shape, but no clear dividing lines permitting the recognition of segregates such as Ribes incertum J.F.Macbr. The only exception are cloud-forest populations of Ribes cuneifolium in Pasco, which we propose to segregate as a new subspecies Ribes cuneifolium subsp. pascoense based on their considerably larger leaves and inflorescences.

El género Ribes (Grossulariaceae) es principalmente distribuido en el hemisferio norte, pero también presente con muchas especies en los Andes tropicales. En los Andes del Perú el género principalmente se encuentra en bosque nublado, el subpáramo, cercos vivos y matorrales de zonas por lo menos estacionalmente húmedos. Sin embargo, algunas especies son presentes en hábitats más extremos, así como matorrales del flanco occidental de los Andes (matorral Andino, Ribes ovalifolium) respectivamente la puna y el páramo altoandino hasta los 5100 m de altitud. (Ribes cuneifolium y algunos segregados dudosos). Estas especies tienen hojas pequeñas, poco divisas, muy atípicas para el género, normalmente provisto de hojas largas, con tres ó cinco lobos profundos. Tanto la distribución como la delimitación de las especies son poco entendidas. El presente estudio presenta una revisión taxonómica de las especies, proponiendo el reconocimiento de solamente dos especies bien diferenciadas. Ribes ovalifolium tiene un rango amplio desde el Norte de Ancash hasta Tacna a lo largo del flanco occidental de los Andes del Perú. Igualmente, demostramos que Ribes cuneifolium representa una sola especie de amplia distribución de grandes alturas desde San Martín/La Libertad hasta Cuzco. Ribes cuneifolium demuestra una diversidad morfológica considerable en detalles del indumento, color de las flores y morfología foliar, pero no encontramos morfotipos claramente delineados justificando la segregación de especies adicionales, como el Ribes incertum J.F.Macbr. Las únicas excepciones son las poblaciones de Ribes cuneifolium del bosque nublado de Pasco. Proponemos el reconocimiento de este material como subespecie Ribes cuneifolium subsp. pascoense basado en sus hojas e inflorescencias mucho más grandes.

New occurrences and habitat description of southern Ecuador endemic frog Atelopus exiguus (Anura: Bufonidae) from a conservation hotspot in the high Andes / Nuevas ocurrencias y descripción del hábitat de la rana endémica del sur de Ecuador Atelopus exiguus (Anura: Bufonidae) en un punto crítico de conservación en los altos Andes

Abstract Atelopus species are classified as a priority taxon for monitoring and conservation, of these A. exiguus is endemic to southern Ecuador and is classified as critically endangered, however, within its known geographic range, little attention has been given to identifying new localities particularly across the páramo ecosystem (> 3500 m a.s.l.). Therefore, in the páramo landscape of Macizo del Cajas Biosphere Reserve, a conservation hotspot, we intensively searched for A. exiguus across 15 localities (elevation range: 3550 - 3800 m a.s.l.). In one year of monitoring (2020 - 2021), we recorded four individuals of A. exiguus (two were tadpoles) in two localities. The localities are characterized by a higher proportion of páramo grassland in association with shrubby páramo as well as cushion páramo; this riparian habitat is related to relatively good water quality (according to Andean Biotic Index), relatively low water temperatures and relatively low water flow. Our findings, accompanied by a detailed monitoring protocol, suggest habitat requirements for A. exiguus. Further intensive surveys beyond the limits of protected areas of Azuay province, especially across the páramos, is emerging as an urgent step to improve conservation decisions.

Resumen Las especies del género Atelopus están clasificadas como un taxón prioritario para su monitoreo y conservación, de ellas A. exiguus es endémica del sur de Ecuador y está clasificada como en peligro crítico de extinción. Sin embargo, dentro de su área de distribución geográfica conocida, poca atención se ha prestado en identificar nuevas localidades, especialmente en el ecosistema del páramo (> 3500 m de altitud). Por lo tanto, en el paisaje de páramo de la Reserva de la Biosfera Macizo del Cajas, un punto caliente de conservación, buscamos intensamente la especie en 15 localidades (rango de elevación: 3550 - 3800 m de altitud). En un año de monitoreo (2020 - 2021), registramos cuatro individuos de A. exiguus (dos fueron renacuajos) en dos localidades. Las localidades se caracterizan por una mayor proporción de pastizales de páramo en asociación con páramo arbustivo, así como páramo de almohadilla; este hábitat ribereño está relacionado con una calidad de agua relativamente buena (según el Índice Biótico Andino), temperaturas de agua relativamente bajas, así como un flujo de agua relativamente bajo. Nuestros hallazgos, acompañados de un protocolo de monitoreo detallado, sugieren los requerimientos de hábitat para A. exiguus. La realización de más estudios intensivos más allá de los límites de las áreas protegidas de la provincia de Azuay, especialmente a través de los páramos, se considera como urgente para mejorar las decisiones de conservación.

Effect of agricultural activities on surface water quality from páramo ecosystems.

Páramos are high mountain ecosystems strategic for water provision in South America. Currently, páramos are under threat due to agricultural intensification that impairs surface water sources. This research analyzed the effect of agriculture (spring onion-Allium fistulosum, potato-Solanum tuberosum, and livestock farming) on water quality in páramo ecosystems. A Hydrographic Unit upstream of the Jordan river catchment (Colombia) was selected and monitored in two different rainfall regimes, following the paired catchments and upstream-downstream approaches to compare water quality from natural and anthropic areas. Twenty-two parameters related to agricultural activities were analyzed (nutrients, salts, organic matter, sediments, and pathogens). The studied agricultural activities increased loads of surface water in quality in nitrates (0.02 to 2.56 mg N-NO3/L), potassium (0.13 to 1.24 mg K/L), and Escherichia coli (63 to 2718 FCU/100 mL), generating risks on the human health and promoting eutrophication. Total nitrogen and organic matter in the rainy season were higher than dry. BOD5, COD, turbidity, and E. coli were above international standards for direct human consumption. However, water could be used for irrigation, livestock watering, and aquatic life ambient freshwater. The results show that a small land-use change of almost 15% from natural páramo vegetation to agricultural uses in these ecosystems impairs water quality, limiting its uses, and the need to harmonize small-scale livelihoods in the páramo with the sustainability of ecosystem service provision.

Characterizing solute budgets of a tropical Andean páramo ecosystem.

Monitoring solute fluxes in water quality studies is essential to reveal potential ecosystem disturbances, and is particularly important in Andean headwater catchments as they are the main sources of water for downstream populations. However, such studies have mainly focused on organic matter and nutrients, disregarding other solutes that can threaten water quality (e.g. arsenic, lead, calcium or magnesium). Additionally, routine low-resolution (weekly or monthly) sampling schemes may overlook important solute dynamics. Therefore, we collected water samples every four hours for the analysis of twenty-four solutes in a pristine tropical Andean páramo catchment. Solute fluxes were calculated using five different methods. The 4-hourly data set was filtered to test for an optimum sampling frequency without compromising export rates. Based on the available 4-hourly data, the results showed that the interpolation export method was best suited, due to a weak correlation with discharges. Of the twenty-four solutes analyzed, Dissolved Organic Carbon (DOC), Total Nitrogen bound (TNb), Si, Ca, Mg, K, and Na presented the highest input rates (with DOC = 4.167E+08 mEq km-2 yr-1 and Si = 1.729E+07 mEq km-2 yr-1) and export rates (with DOC = 2.686E+08 mEq km-2 yr-1 and Si = 2.953E+08 mEq km-2 yr-1). Moreover, DOC, TNb, NH4-N, NO2-N, NO3-N, PO4, Al, B, Cu, Fe, Zn, As, Cd, Cr, Pb, and V presented more input than export, while Ca, K, Mg, Na, Rb, Si, Sr, and Ba presented more export than input (geogenic sources). Filtered sampling frequencies demonstrated that a minimum of daily grab samples would be required to obtain reliable export rates with differences consistently below 10%, when compared to the 4-hourly solute export. These findings can be particularly useful for the implementation of long-term monitoring programs at low cost, and they provide high-quality information, for the first time, on biogeochemical budgets in a pristine páramo catchment.

Prospection of Psychrotrophic Filamentous Fungi Isolated from the High Andean Paramo Region of Northern Ecuador: Enzymatic Activity and Molecular Identification.

The isolation of filamentous fungal strains from remote habitats with extreme climatic conditions has led to the discovery of a series of enzymes with attractive properties that can be useful in various industrial applications. Among these, cold-adapted enzymes from fungi with psychrotrophic lifestyles are valuable agents in industrial processes aiming towards energy reduction. Out of eight strains isolated from soil of the paramo highlands of Ecuador, three were selected for further experimentation and identified as Cladosporium michoacanense, Cladosporium sp. (cladosporioides complex), and Didymella sp., this last being reported for the first time in this area. The secretion of seven enzymes, namely, endoglucanase, exoglucanase, ß-D-glucosidase, endo-1,4-ß-xylanase, ß-D-xylosidase, acid, and alkaline phosphatases, were analyzed under agitation and static conditions optimized for the growth period and incubation temperature. Cladosporium strains under agitation as well as incubation for 72 h mostly showed the substantial activation for endoglucanase reaching up to 4563 mU/mL and xylanase up to 3036 mU/mL. Meanwhile, other enzymatic levels varied enormously depending on growth and temperature. Didymella sp. showed the most robust activation at 8 °C for endoglucanase, ß-D-glucosidase, and xylanase, indicating an interesting profile for applications such as bioremediation and wastewater treatment processes under cold climatic conditions.

Passive multi-unit field-pilot for acid mine drainage remediation: Performance and environmental assessment of post-treatment solid waste.

This study evaluated the performance of a passive multi-unit field-pilot operating for 16 months to treat acid mine drainage (AMD) from a coal mine in Colombia Andean Paramo. The multi-unit field-pilot involved a combination of a pre-treatment unit (550 L) filled with dispersed alkaline substrate (DAS), and six passive biochemical reactors (PBRs; 220 L) under two configurations: open (PBRs-A) and closed (PBRs-B) to the atmosphere. The AMD quality was 1200 ± 91 mg L-1 Fe, 38.0 ± 1.3 mg L-1 Mn, 8.5 ± 1.6 mg L-1 Zn, and 3200 ± 183.8 mg L-1 SO42-, at pH 2.8. The input and output effluents were monitored to establish AMD remediation. Physicochemical stability of the post-treatment solids, including metals (Fe2+, Zn2+, and Mn2+) and sulfates for environmental contamination from reactive mixture post-treatment, was also assessed. The passive multi-unit field-pilot achieved a total removal of 74% SO42-, 63% Fe2+, and 48% Mn2+ with the line of PBRs-A, and 91% SO42-, 80% Fe2+, and 66% Mn2+ with the line of PBRs-B, as well as 99% removal for Zn2+ without significant differences (p < 0.05) between the two lines. The study of the physicochemical stability of the post-treatment solids showed they can produce acidic leachates that could release large quantities of Fe and Mn, if they are disposed in oxidizing conditions; contact with water or any other leaching solutions must be avoided. Therefore, these post-treatment solids cannot be disposed of in a municipal landfill. The differences in configuration between PBRs, open or closed to the atmosphere, induced changes in the performance of the passive multi-unit field-pilot during AMD remediation.

Reflexiones sobre las perspectivas de sostenibilidad ambiental e institucional para la planeación territorial de los sistemas socioecológicos de páramo y bosque altoandino en colombia / Reflections on the perspectives of environmental and institutional sustainability for territorial planning of the socioecological systems of the páramo and high Andean forest in Colombia

Resumen Los sistemas socioecológicos (SSE) de páramo y bosque altoandino en Colombia son sistemas ecológicos que se caracterizan por sus particularidades de estructura, composición y funcionamiento. Son espacios que se han desarrollado como parte de procesos históricos de relación entre los humanos y la naturaleza, lo cual ha determinado lo que son al día de hoy. Este artículo realiza un análisis de las perspectivas y discursos producidos desde los gobiernos y las políticas públicas en torno a la sostenibilidad ambiental, la institucionalidad y la planeación territorial que se emplean para gestionar los territorios con presencia de estos socioecosistemas.

Abstract Socioecological systems (SSE) of paramo and high Andean forest in Colombia are ecological systems that are characterized by their particularities of structure, composition and functioning. These spaces have been developed as part of historical processes and relationship between humans and nature. These relations have determined their actual status. In this article we analyze the government's perspectives and postures around environmental sustainability, institutions and territorial planning that are used to govern and decide on important matters as the territory and its interaction with SSEs.