RESUMEN El estudio de la estructura y diversidad de los ecosistemas forestales es fundamental para comprender el funcionamiento y dinámica de los bosques. Se describió la estructura y diversidad de especies leñosas en diferentes tipos de curso de agua a lo largo del río Santa Catarina en Nuevo León, México. Se identificaron tres condiciones hidrológicas: permanente (I), semipermanente (II) y temporal (III). En cada condición se establecieron 14 sitios rectangulares de 1 000 m2, todas las especies de cada sitio fueron identificadas. Se midió el diámetro de la copa de cada individuo, el Índice de Valor de Importancia (IVI) de condición. La riqueza y diversidad de especies fue calculada con los índices de Margalef (D Mg ) y Shannon-Wiener (H'). Además, se determinó la similitud entre condiciones con el índice de Sorensen (Is). Se identificaron 32 especies, 29 géneros y 16 familias. La condición I registró mayor riqueza específica y diversidad con 28 especies y un valor de diversidad H' = 2.41 ± 0.710, en donde Salix nigra presentó el mayor IVI. La condición II presentó la mayor riqueza de Margalef con un valor D Mg de 1.77 ± 0.22. En la condición III Leucaena leucocephala fue la especie más importante. La similitud entre condiciones fue mayor al 50%. Los resultados demuestran la variación estructural de la vegetación en diferentes regímenes hidrológicos, lo cual constituye una base sólida para futuras investigaciones sobre el desarrollo de la vegetación asociada al río Santa Catarina, y otras áreas riparias del norte de México.

ABSTRACT The study of the structure and diversity of forest ecosystems is essential to understand the functioning and dynamics of forests. The structure and diversity of woody species in different types of watercourses along the Santa Catarina river in Nuevo Leon, Mexico were described. Three conditions were identified: permanent (I), semi-permanent (II) and temporary (III). In each condition, 14 rectangular sites of 1 000 m2 were established. All species were identified. The crown diameter of each individual was measured. The Importance Value Index (IVI) was determined for each condition. Species richness and diversity was calculated with the Margalef (D Mg ) and Shannon-Wiener (H') indices. In addition, the similarity between conditions was determined using the Sorensen index (Is). 32 species, 29 genus and 16 families were identified. Condition I recorded greater specific richness and greater diversity with 28 species and a diversity value H' = 2.41 ± 0.710, where Salix nigra presented the highest IVI. Condition II presented the highest Margalef richness with a D Mg value = 1.77 ± 0.22. In condition III Leucaena leucocephala turned out to be the most important species. The similarity between conditions was greater than 50%. The results demonstrate the structural variation of the vegetation in different hydrological regimes, which constitutes a solid base for future investigations on the development of the vegetation associated with the Santa Catarina river, and other riparian areas of north of Mexico.

ABSTRACT This paper attempts to explain the role of the house in the village in the territorial dynamics around the mobility of peasant groups. The focus is centered in those that inhabit rural dwellings, near the villages Santa Isabel and Algarrobo del Águila (La Pampa, Argentina). Likewise, it pretends to expose the spatial characteristics that exhibit the reproduction of the peasant territoriality in the house in the village. Thus, it analyzes, through a qualitative methodology, the social groups whose puestos are located near two branches of the Atuel River (the stream of La Barda and the Atuel Viejo), in the west of La Pampa province. Besides the field trips that were made in the study area between 2009 and 2022, it includes testimonies of peasant families, public officers and territorial technicians, along with documents, cartography and statistics.

RESUMEN Este trabajo busca explicar el rol de las casas de pueblo en las dinámicas territoriales gestadas en torno a las movilidades de los grupos campesinos que habitan en puestos rurales próximos a las localidades de Santa Isabel y Algarrobo del Águila (La Pampa, Argentina). Asimismo, pretende exponer las características espaciales que dan cuenta de la reproducción de la territorialidad campesina en la casa de pueblo. Para ello se analizan, a través de metodología cualitativa, los grupos sociales cuyos puestos se localizan próximos a dos brazos del río Atuel (el arroyo de la Barda y el Atuel Viejo), en el oeste de la provincia de La Pampa. Además del trabajo de campo realizado en la zona de estudio entre los años 2009 y 2022, se incluyen testimonios de familias campesinas, funcionarios/as y técnicos/as territoriales, junto con documentación, cartografía y estadísticas.

Resumen Los isótopos radiactivos son utilizados en diversos procesos, como en tratamientos médicos nucleares. Después de su uso, dichos isótopos pueden ser descargados en las aguas residuales, ocasionando problemas ambientales y de salud humana. El objetivo de este trabajo fue identificar la presencia de emisiones alfa y beta totales en el río Santa Catarina, Monterrey, Nuevo León, México, como referencia para conocer si existe riesgo para la salud de la población debido a estas descargas de radionúclidos en el agua residual. Se recolectaron muestras puntuales por conveniencia en seis sitios de descarga de agua durante la época de invierno y verano y se trasladaron al Laboratorio ABC para su análisis. Las emisiones alfa y beta variaron conforme a la estación del año, encontrándose concentraciones más altas en verano tanto de alfas como betas de 0.551 Bq/l y 0.842 Bq/l, respectivamente. Ningún valor superó los límites permitidos por la normatividad mexicana para elementos radiactivos, por lo que no representan un riesgo para la salud.

Abstract Radioactive isotopes are used in various processes such as nuclear medical treatments. After their use, these isotopes can be discharged into wastewater, causing environmental and human health problems. The objective of this work was to identify the presence of total alpha and beta emissions in the Santa Catarina River, Monterrey, Nuevo Leon, Mexico, as a reference to know if there is a risk to the health of the population due to these radionuclide discharges in wastewater. Point samples were collected for convenience at six water discharge sites during the winter and summer seasons and taken to the ABC Laboratory for analysis. The alpha and beta emissions varied according to the season of the year, with higher concentrations of both alphas and betas in summer of 0.551 Bq/l and 0.842 Bq/l, respectively. None of the values exceeded the limits allowed by Mexican regulations for radioactive elements and therefore do not represent a health risk.

Abstract The indigenous communities of the Colombian Amazon East maintain their traditional knowledge for the use of their resources. Insects have been used as an alternative food that has been included as part of their daily diet. Fourteen species of edible insects belonging to 15 families of five orders were recorded in the communities of Santa María de Itapinima and Piracemo, located on the he Cuduyarí River in the department of Vaupés. According to its use value, mojojoy Rhynchophorus palmarum (L.) (Coleoptera: Curculionidae), manivara Syntermes spinosus (Latreille) (Blattodea: Termitidae), leaf-cutting ant Atta laevigata(F. Smith) (Hymanoptera: Formicidae) and several species of moth caterpillars (Lepidoptera) commonly called as tapurú, are the most important species of edible insects. For each species, its ecological calendar was established, and its collecting techniques and methods, and traditional forms of preparation and consumption were documented. Through community pedagogical workshops, strategies for the conservation and sustainable use of edible insects were proposed, identifying research priorities in order to improve the food security of communities.

Resumen Las comunidades indígenas del oriente amazónico colombiano, mantienen sus conocimientos tradicionales para el uso y aprovechamiento de sus recursos. Los insectos han sido empleados como una fuente de alimento alternativa que ha sido incluida como parte de su dieta diaria. En las comunidades de Santa María de Itapinima y Piracemo, localizadas sobre el río Cuduyarí en el departamento del Vaupés, se registraron 14 especies de insectos comestibles pertenecientes a 10 familias y cinco órdenes: Coleoptera, Blattodea, Hymenoptera, Lepidoptera y Hemiptera. De acuerdo con su valor de uso, las especies de insectos comestibles más importantes son el mojojoy Rhynchophorus palmarum (L.) (Coleoptera: Curculionidae), la manivara Syntermes spinosus (Latreille) (Blattodea: Termitidae), la hormiga arriera Atta laevigata (F. Smith) (Hymanoptera: Formicidae) y varias especies de orugas de polillas (Lepidoptera) llamadas comúnmente como tapurú. Se reportan nueve especies de insectos comestibles que son nuevos registros para Colombia y para el mundo. Para cada especie, se estableció su calendario ecológico, y se documentaron sus técnicas y métodos de recolecta, y sus formas tradicionales de preparación y consumo. Mediante talleres pedagógicos comunitarios, se plantearon estrategias de conservación y uso sostenible de insectos comestibles, identificando prioridades de investigación para mejorar la seguridad alimentaria de las comunidades.

Abstract: From 1526 to 1529, Alonso de Santa Cruz (1505-1567) took part in the expedition that Sebastián Caboto commanded towards the Solís river, as a trustee (veedor) and treasurer. Later on, while appointed as cosmographer by the Casa de la Contratación de Sevilla and of the Spanish king himself, Santa Cruz wrote the Islario general… (c. 1560), an ambitious cosmographic work in which he included a chorographic description of Brazil and the renamed La Plata river. In addition, he composed a draft containing instructions pertained to the accurate description of the Indies. Considering these instances and the different roles that Santa Cruz played in them, we will analyze both the complex links between exploration experience, cosmographic knowledge, and raison d’état, on one hand, and the broader and more complex problem of the production of an accurate representation of the New World, on the other.

Resumen: Entre 1526 y 1529 Alonso de Santa Cruz (1505-1567) formó parte, como veedor y tesorero, de la expedición que Sebastián Caboto dirigió al Río de Solís. Luego, ya como cosmógrafo de la Casa de la Contratación de Sevilla y del propio rey español, escribió su Islario general… (c. 1560), un ambicioso trabajo cosmográfico en el que incluyó una descripción corográfica del Brasil y del ya rebautizado Río de la Plata. Además, redactó un borrador con instrucciones relativas a la correcta descripción general de las Indias. El análisis de estas instancias y los diversos roles que en ellas cumplió Santa Cruz, nos permite considerar tanto los densos vínculos establecidos entre experiencia de explotación, saber cosmográfico y razón de estado, de un lado, como el problema más general y complejo de la producción de una adecuada representación del Nuevo Mundo, de otro.

Resumo A leptospirose é uma zoonose que apresenta potencial epidêmico, principalmente após fortes chuvas que acarretam inundações, alagamentos e enxurradas. Algumas características da região costeira de Santa Catarina, localizada no Sul do Brasil, influenciam nesses processos. Portanto, a partir do estudo da leptospirose nos seis municípios do estado com as maiores incidências e picos epidêmicos de 2000 a 2015, buscou-se conhecer a tendência dessa doença e as variáveis climáticas e ambientais associadas à sua ocorrência, ajustando dois modelos com resposta binomial negativa. As maiores incidências foram encontradas em 2008 e 2011, com picos no mesmo mês ou no posterior aos eventos de desastres. A incidência apresentou forte comportamento sazonal, sendo maior nos meses do verão. Observou-se tendência de queda na incidência dos municípios estudados, estimada em 3,21% ao ano. Os fatores climáticos e ambientais mais fortemente associados foram o número de dias de chuva, a temperatura máxima e a presença de enxurrada e de inundação, com diferentes impactos entre os municípios. Houve interações significativas, indicando que o efeito de inundações na incidência não é o mesmo em todos os municípios e que as diferenças nas incidências entre os municípios dependem da ocorrência ou não de inundações.

Abstract Leptospirosis is a zoonosis with epidemic potential, especially after heavy rainfall causing river, urban and flash floods. Certain features of Santa Catarina’s coastal region influence these processes. Using negative binomial regression, we investigated trends in the incidence of leptospirosis in the six municipalities with the highest epidemic peaks between 2000 and 2015 and the climatic and environmental variables associated with the occurrence of the disease. Incidence was highest in 2008 and 2011, and peaks occurred in the same month or month after disasters. Incidence showed a strong seasonal trend, being higher in summer months. There was a decrease trend in incidence across the six municipalities (3.21% per year). The climatic and environmental factors that showed the strongest associations were number of rainy days, maximum temperature, presence of flash floods, and river flooding. The impact of these variables varied across the municipalities. Significant interactions were found, indicating that the effect of river flooding on incidence is not the same across all municipalities and differences in incidence between municipalities depend on the occurrence of river flooding.

ABSTRACT: 500 years after the Magallanes-Elcano Expedition along the South American coasts, we analyzed the vernacular records of biological species reported in the Relación of this trip, written by Antonio Pigafetta, in addition to the Derrotero, by Francisco Albo. We found 40 vernacular names corresponding to 42 scientifically nominated species (13 plants, 12 birds, 6 fishes, 9 mammals, and 2 mollusks). Most of these records come from Bahía de Santa Lucía (Brazil) and Bahía de San Julián (Argentina), followed by Estrecho de Magallanes (Chile), Santa Cruz River and Santa María Cape (Argentina). Out of 42 species, 26 (62%) are currently in some category of conservation concern, according to the IUCN.

RESUMEN: A 500 años del paso de la Expedición Magallanes-Elcano por las costas sudamericanas, analizamos los registros vernaculares de especies biológicas consignados en la Relación del viaje, escrita por Antonio Pigafetta, en complemento con el Derrotero de Francisco Albo. Encontramos 40 vernáculos correspondientes a 42 especies nominadas científicamente (13 plantas, 12 aves, 6 peces, 9 mamíferos y 2 moluscos). Estos registros, en su mayor parte, proceden de las bahías de Santa Lucía (Brasil) y San Julián (Argentina), seguidos del Estrecho de Magallanes (Chile), río de Santa Cruz y cabo de Santa María (Argentina). De las 42 especies reconocidas, 26 (62%) se encuentran actualmente en alguna categoría de conservación, generalmente preocupante, de acuerdo con la IUCN.

Resumo A leptospirose é uma zoonose que apresenta potencial epidêmico, principalmente após fortes chuvas que acarretam inundações, alagamentos e enxurradas. Algumas características da região costeira de Santa Catarina, localizada no Sul do Brasil, influenciam nesses processos. Portanto, a partir do estudo da leptospirose nos seis municípios do estado com as maiores incidências e picos epidêmicos de 2000 a 2015, buscou-se conhecer a tendência dessa doença e as variáveis climáticas e ambientais associadas à sua ocorrência, ajustando dois modelos com resposta binomial negativa. As maiores incidências foram encontradas em 2008 e 2011, com picos no mesmo mês ou no posterior aos eventos de desastres. A incidência apresentou forte comportamento sazonal, sendo maior nos meses do verão. Observou-se tendência de queda na incidência dos municípios estudados, estimada em 3,21% ao ano. Os fatores climáticos e ambientais mais fortemente associados foram o número de dias de chuva, a temperatura máxima e a presença de enxurrada e de inundação, com diferentes impactos entre os municípios. Houve interações significativas, indicando que o efeito de inundações na incidência não é o mesmo em todos os municípios e que as diferenças nas incidências entre os municípios dependem da ocorrência ou não de inundações.

Abstract Leptospirosis is a zoonosis with epidemic potential, especially after heavy rainfall causing river, urban and flash floods. Certain features of Santa Catarina’s coastal region influence these processes. Using negative binomial regression, we investigated trends in the incidence of leptospirosis in the six municipalities with the highest epidemic peaks between 2000 and 2015 and the climatic and environmental variables associated with the occurrence of the disease. Incidence was highest in 2008 and 2011, and peaks occurred in the same month or month after disasters. Incidence showed a strong seasonal trend, being higher in summer months. There was a decrease trend in incidence across the six municipalities (3.21% per year). The climatic and environmental factors that showed the strongest associations were number of rainy days, maximum temperature, presence of flash floods, and river flooding. The impact of these variables varied across the municipalities. Significant interactions were found, indicating that the effect of river flooding on incidence is not the same across all municipalities and differences in incidence between municipalities depend on the occurrence of river flooding.

Abstract River processes have the ability to modify all terrestrial systems. The release of components, their transport and deposition as sediments by water have important environmental consequences, many of which can be deteriorating or irreversible. Arid regions are susceptible to water erosion, since the mere existence of water flow is exceptional and the common situation is its extreme speed, which is combined with the spatio-temporal variability of sediment transport. In this context, the objective was to analyze the dynamics of sediment transport in the Lorohuasi river basin, Cafayate, Salta, in the middle sections of the Alisal and Colorado tributaries, throughout the Lorohuasi river and the river mouth in the Santa María river, between the years 2016 and 2020. In 30 plots of 1 m2 located in 14 study sites, 30 samples of medium and fine sediments were collected in the active channel of the rivers. At each site, the width and slope of the channel was measured, as well as the flow, with the granulometric data of the medium sediments, were constructed accumulated frequency graphs and tables of statistical parameters (mean, median, mode, standard deviation, asymmetry and kurtosis), in order to characterize and analyze the distribution of the granulometric fractions along the river courses, evaluate the sedimentation dynamics and characterize the transport agent. The results show that in general lines, the mean granulometry of all the analyzed material transported in the Lorohuasi river basin is mean sand (phi 1.15), with mean-median-mode in the same fraction, the distribution is mesokurtic, symmetric and the material is poorly selected. The sediment is transported majorly by saltation in the Colorado and Alisal rivers, and by saltation and/or suspensión in the Lorohuasi river. It is concluded that the physical characteristics of the basin and anthropic activities influence the granulometry of the analyzed sediments, especially in the lower basin, and that rehabilitation techniques in affected riverbank areas could restore their functionality and protect the river system.

Resumen Los procesos fluviales tienen la capacidad de modificar todos los sistemas terrestres. La libe ración de componentes, su transporte y depositación como sedimentos por el agua, tienen consecuencias ambientales importantes, muchas de las cuales pueden ser deteriorantes o irreversibles. Las regiones áridas son susceptibles a la erosión hídrica, ya que la sola existencia de flujo ácueo es excepcional y la situación común es su extrema velocidad, que se conjuga con la variabilidad espacio-temporal del transporte de sedi mentos. En este contexto, el objetivo fue analizar la dinámica en el transporte de sedimentos en la cuenca del río Lorohuasi, Cafayate, Salta, en los tramos medio de los tributarios Alisal y Colorado, en todo el río Lorohuasi y el sector de desembocadura con el río Santa María, entre los años 2016 y 2020. En 30 parcelas de 1 m2 ubicadas en 14 sitios de estudios, se recolectaron 30 muestras de sedimentos medianos y finos en el cauce activo de los ríos. En cada sitio se midió el ancho y pendiente del cauce, como así también el caudal; con los datos granulométricos de los sedimentos medianos se construyeron gráficos de frecuencia acumu lada y tablas de parámetros estadísticos (media, mediana, moda, desviación estándar, asimetría y curtosis), a fin de caracterizar y analizar la distribución de las fracciones granulométricas a lo largo de los cursos fluviales, evaluar la dinámica de sedimentación y caracterizar el agente de transporte. Los resultados ex ponen que en general, la granulometría media de todo el material analizado transportado en la cuenca del río Lorohuasi es arena media (phi 1,15), con media-mediana-moda en la misma fracción, la distribución es mesocúrtica, simétrica y el material es pobremente seleccionado. El sedimento se transporta mayormente por saltación en los ríos Colorado y Alisal, y por saltación y/o suspensión en el río Lorohuasi. Se concluye que las características físicas de la cuenca y las actividades antrópicas influyen en la granulometría de los sedimentos analizados, especialmente en la cuenca baja, y que técnicas de rehabilitación en las riberas afectadas podrían devolver la funcionalidad de las mismas y proteger el sistema fluvial.

ABSTRACT Background: The Zoque rainforest Chimalapas is located in the Isthmus of Tehuantepec, mainly in the municipalities of San Miguel Chimalapa and Santa María Chimalapa in the state of Oaxaca, is considered one of the latest well-preserved regions in Mexico, as well as a center of diversity and endemism of flora and fauna. Objective: Develop inventories of the ichthyofauna from Santa María Chimalapa rainforest to catalog resources before imminent environmental and human alterations. Methods: Samples were collected using several types of fishing gears in the main rivers and tributaries of the water system. Results: A total of 2,430 fish were collected, corresponding to 38 species, grouped in 31 genera, 19 families, and 12 orders. The families with the greatest species richness were Cichlidae and Poeciliidae with nine and six. Priapella intermedia was the most abundant (30.1% total), followed by Astyanax finitimus (13.3%) and Pseudoxiohophorus bimaculatus (10.3%). Regarding biogeographical aspects of the fish community, a prevalence of neotropical species (91.9%) was observed, two species of Nearctic origin (Ictalurus meridionalis and Ictiobus meridionalis) and four vicarious species (Atherinella sallei, Cathorops cf. kailolae, Eugerres mexicanus, Strongylura hubbsi). 31 species are being evaluated in some risk categories and two are exotic. Conclusions: The ichthyofauna of Santa María Chimalapa holds similarities to that of the aquatic bodies present in rainforests of southern Mexico. However, ecological, conservation and anthropogenic impact studies are necessary to establish sustainable conservation strategies.

RESUMEN Antecedentes: La Selva Zoque de Los Chimalapas se encuentra en la región del Istmo de Tehuantepec, principalmente en los municipios de San Miguel Chimalapa y Santa María Chimalapa en el estado de Oaxaca, es considerada una de las últimas áreas mejor conservadas en México, así como un centro de diversidad botánica y faunística. Objetivo: Inventariar la ictiofauna de la Selva de Santa María Chimalapa para contribuir al conocimiento de este grupo en la región. Métodos: Los muestreos se realizaron empleando diversas artes de pesca, en los principales ríos y tributarios que se encuentran en el municipio. Resultados: Se recolectaron 2,430 peces, correspondientes a 38 especies, agrupadas en 31 géneros, 19 familias y 12 órdenes. Las familias con la mayor riqueza específica fueron Cichlidae y Poeciliidae con nueve y seis especies. Priapella intermedia fue la especie más abundante (30.1% del total), seguida por Astyanax finitimus (13.3%) y Pseudoxiphophorus bimaculatus (10.3%). Con respecto a los aspectos biogeográficos del conjunto íctico, se observó un predominio de especies neotropicales (91.9%), dos especies de origen neártico (Ictalurus meridionalis e Ictiobus meridionalis) y cuatro vicarias (Atherinella sallei, Cathorops cf . kailolae, Eugerres mexicanus y Strongylura hubbsi), 31 especies se encuentran evaluadas en alguna categoría de riesgo y dos son exóticas. Conclusiones: La ictiofauna de Santa María Chimalapa es similar al de los cuerpos acuáticos presentes en selvas del sur de México. Son necesarios estudios ecológicos, de conservación e impacto antropogénico para establecer estrategias sustentables de conservación.

Resumo As metodologias de classificação do relevo, buscam definir parâmetros que determinam porções da superfície que apresentem características homogêneas quanto as formas e elementos. O desenvolvimento acelerado das geotecnologias, possibilita cada vez mais o uso de ferramentas e metodologias que permitem o auxílio de estudos relacionados ao relevo. O presente trabalho possui como objetivo a proposição metodologia da classificação do relevo em três níveis taxonômicos, utilizando processamento automatizados em ambiente SIG. A presente proposição foi aplicada em um estudo de caso na bacia hidrográfica do rio Santa Maria, oeste do Rio Grande do Sul. Para o processamento digital dos dados utilizou-se sistema de informações geográficas ArcGIS® e a base do Modelo Digital de Elevação foram os dados do Radar SRTM de 3 arc-second (90 metros). O processamento para o primeiro táxon foi utilizado através dos dados de amplitude e declividade para definir quatro formas de relevo, sendo elas: áreas planas, colinas levemente onduladas, colinas onduladas e associação de morros e morrotes. No segundo nível taxonômico definiu-se dez elementos de relevo denominados: áreas planas, pico, crista, ressalto, crista secundária, encosta, escavado, base da encosta, vale e fosso. No terceiro nível taxonômico foram definidas as formas das vertentes em oito unidades através dos parâmetros de declividade, perfil e plano de curvatura. O processamento em SIG permitiu de forma rápida e precisa estabelecer as formas de relevo, os elementos de relevo e as formas das vertentes, além da relação entre os três níveis taxonômicos.

Abstract Relief classification methodologies seek to define the parameters that determine those parts of the terrestrial surface that present homogeneous forms and elements. The rapid development of geotechnology has increasingly provided tools and methodologies that assist in studies related to relief. The present work proposes a methodology to classify the relief in three taxonomic levels, using automated processing in a GIS environment. This procedure was applied in a case study of the Santa Maria River basin, in the west of Rio Grande do Sul State, Brazil. The digital data processing employed was the Geographic Information System ArcGIS® and the data from the SRTM 3 arc-second radar (90 meters) was the basis for the Digital Elevation Model. The processing for the first taxon used the amplitude and slope data to define four forms of relief: flat areas, slightly undulating hills, undulating hills, and hills with buttes and larger hills. In the second taxonomic level, ten relief elements were identified: flat, peak, ridge, shoulder, spur, slope, hollow, footslope, valley, and pit. In the third taxonomic level, the slope forms were characterized into eight units using the slope, profile, and curvature plane parameters. It was possible to detect the three proposed levels, the relief forms, relief elements, and slope forms. GIS processing offers a fast and precise definition of the relief forms and elements, and the slope forms, as well as the relationship between the three taxonomic levels.

Resumen Les méthodologies de classification des reliefs cherchent à définir des paramètres qui déterminent les portions de la surface qui présentent des caractéristiques homogènes en termes de formes et d'éléments. Le développement accéléré des géotechnologies, permet de plus en plus l'utilisation d'outils et de méthodologies qui permettent l'aide d'études liées au relief. Ce travail vise à proposer une méthodologie de classification des reliefs à trois niveaux en utilisant un traitement automatisé dans un environnement SIG. La présente proposition a été appliquée dans une étude de cas dans le bassin hydrographique de la rivière Santa Maria, à l'ouest de Rio Grande do Sul. Pour le traitement numérique des données a été utilisé système d'information géographiqueet ArcGIS® et la base du modèle numérique d'élévation était les données du radar SRTM 3 secondes d'arc (90 mètres). Le traitement de la première catégorie d'analyse a été utilisé à travers les données d'amplitude et de pente pour définir quatre formes de relief, à savoir: les zones plates, les collines légèrement vallonnées, les collines vallonnées et l'association des buttes et petites buttes. Au deuxième niveau d'analyse, dix éléments de relief ont été définis: zones planes, pic, crête, épaule, arête secondaire, pente, excavé, base de la pente, vallée et fossé. Au troisième niveau sont définies les formes des pentes en huit unités à travers les paramètres le profil et plan. Le traitement SIG a permis d'établir rapidement et avec précision les formes en relief, les éléments en relief et les formes des pentes, en plus de la relation entre les trois niveaux d'analyse.

Resumen La riqueza hídrica de la zona centro-oriente de Morelos ha permitido el aprovechamiento de los manantiales y del río Cuautla para el establecimiento del cultivo de berro (Nasturtium officinale R. Br.) en el municipio de Cuautla, donde la siembra de esta hortaliza tiene más de 70 años. Sin embargo, es escasa la información sobre el sistema de producción y el impacto económico en la región. El objetivo de esta investigación fue describir aspectos sociales, técnicos y de comercialización sobre el cultivo de berro producido en el municipio de Cuautla, Morelos. La investigación se realizó en el año 2018. Se entrevistó a productores y se realizaron visitas a sus unidades de producción. Lo anterior permitió obtener información sobre aspectos relacionados con la producción, comercialización y beneficios económicos. Los ejidos productores de berro son Cuautla, Cuautlixco y Santa Inés. Existen dos asociaciones y algunos productores independientes, quienes han dispersado esta hortaliza en toda la zona productora, así como su manejo agronómico y centros de venta. La producción de berro en la región no figura en las estadísticas estatales, pero esta actividad agrícola genera beneficios económicos y empleos. La información recabada permitió conocer mejor el sistema de produccción de berro, con lo que se podrán proponer alternativas para un mejor manejo.

Summary The water wealth of the central-eastern area of Morelos has allowed the use of the springs and the Cuautla river for growing watercress (Nasturtium officinale R. Br.) in the municipality of Cuautla, where the planting of this vegetable is more than 70 years old. However, information on the production system and the economic impact in the region is scarce. The aim of this research was to describe social, technical and marketing aspects of watercress grown in the municipality of Cuautla, Morelos. The research was carried out in 2018. Growers were interviewed and visits were made to their production units. The above allowed to obtain information on aspects related to production, commercialization and economic benefits. Watercress producing ejidos are Cuautla, Cuautlixco and Santa Inés. There are two associations and some independent growers, who have dispersed this vegetable throughout the production area, as well as its agronomic management and markets. Watercress production in the region is not included in state statistics but this agricultural activity generates economic benefits and jobs. The information collected will allowed to know better the watercress production system, which will allow us to propose alternatives to improve its management.

RESUMO O presente trabalho teve como objetivo avaliar a composição florística da mata ciliar remanescente da Sanga Lagoão do Ouro, procurando obter informações acerca de sua degradação, analisando a distribuição das espécies nos diferentes estratos florísticos, a regeneração natural e a presença de espécies exóticas. O estudo foi realizado na mata ciliar da Sanga Lagoão do Ouro, tributário de 3ª ordem do Vacacaí-mirim. Sua nascente localiza-se em área urbana, percorrendo várias vilas, o Campus da UFSM, além de uma extensa área rural. Os solos predominantes classificam-se como: Argissolos Bruno-Acinzentados, Vermelho-Amarelos e Vermelhos, além de Planossolos Háplicos, sendo estes de baixa fertilidade natural e bastante suscetíveis à erosão hídrica. O levantamento florístico ocorreu em 12 parcelas de 300 m2 cada, demarcadas ao longo da margem da Sanga Lagoão do Ouro, em que foram avaliados os estratos: plântulas, regeneração natural e arbóreo. O levantamento florístico mostrou haver degradação da mata ciliar, evidenciada pelo baixo número de espécies nativas, pela má distribuição das espécies nos diferentes estratos e pela grande presença de espécies exóticas. Possuem maior potencial de regeneração natural nas espécies que apresentaram maior frequência e que aparecem nos três estratos florísticos levantados, tais como: Eugenia uniflora, Allophylus edulis (A.St.-Hil., Cambess. & A. Juss.) Radlk, Psidium guajava L., Cestrum strigilatum Ruiz & Pav., Prunus myrtifolia (L.) Urb., Zanthoxylum rhoifolium Lam., Casearia sylvestris Sw., Cupania vernalis Cambess. e Schinus terebinthifolius Raddi.

ABSTRACT This work aimed to evaluate the floristic composition of the remaining riparian forest of a stream called ‘Sanga Lagoão do Ouro’, seeking to obtain information about its degradation, analyzing the distribution of the species in the different floristic strata, the natural regeneration and the exotic species presence. The study was conducted at the riparian forest of ‘Sanga Lagoão do Ouro’, which is tributary of the third order of ‘Vacacaí-mirim’ River. Its spring is located in an urban area, covering several villages, the campus of Federal University of Santa Maria as well as an extensive rural area. The predominant soils are classified as: Bruno-Grayish (Bruno-Acinzentados), Red-Yellow (Vermelho-Amarelos) and Red (Vermelhos) Alfisols (Argissolos) and Udalf soil (Planossolos Háplicos), which are of low natural fertility and quite susceptible to water erosion. The floristic surveying was accomplished in 12 sampling plots of 300 m2 each, demarcated along the margin of the stream where the strata were evaluated: seedlings, natural regeneration and arboreal. The floristic survey shows degradation of the studied riparian forest, which is evidenced by the low number of native species, the poor distribution of the species in the different strata and the great presence of exotic species. The species that present the highest frequency and which appear in the three floristic strata mentioned in this study have greater for natural regeneration, such as: Eugenia uniflora, Allophylus edulis, Psidium guajava, Cestrum strigilatum, Prunus myrtifolia, Zanthoxylum rhoifolium, Casearia sylvestris, Cupania vernalis and Schinus terebinthifolius.

Resumen En estudios anuales sobre el fitoplancton realizados en la Ciénaga Grande de Santa Marta (CGSM), costa caribe colombiana, en 1987 y 1995, en los que se hicieron análisis cualitativos y cuantitativos y se establecieron las relaciones con variables fisicoquímicas, entre ellas la salinidad, se concluyó que la variación del diámetro de Actinocyclus normanii está ligada a la variación de la salinidad del agua. Así, las células pequeñas se generan cuando la salinidad baja durante la estación lluviosa, y las grandes lo hacen cuando la salinidad se incrementa, durante la estación seca. Las células pequeñas y las grandes son el resultado de la reproducción asexual y sexual, respectivamente. Durante la reproducción asexual, A. normanii se divide profusamente y se generan las células pequeñas. Durante la reproducción sexual, se generan las auxosporas, que dan lugar a las células grandes. Las auxosporas no se generan por debajo de 8 USP, pero sí lo hacen por encima de este valor, hasta cerca de 30 USP. Se hicieron, también, bioensayos en el laboratorio con A. normanii para establecer su relación con la salinidad y se llegó a los mismos resultados hallados en el medio natural: las auxosporas no se generaron en una concentración salina de 2.8 USP, pero sí en concentraciones de 10 y 20 USP. Con el fin de probar la utilidad de la medición del diámetro de A. normanii en función de la salinidad como herramienta aplicada a la interpretación de paleoambientes, se midieron 300 valvas de A. normanii que se hallaban en 15 placas permanentes de diatomeas obtenidas a partir de las muestras de sedimento de un núcleo de 6 m de profundidad en la desembocadura del río Sevilla (río Frío), en octubre de 2010. Para la prueba del método, se escogieron placas dentro de los primeros 265 cm del núcleo (ca. 2.300 años antes del presente [AP]). Con base en la definición de un diámetro de 40 µm en promedio como el punto de inflexión entre las células pequeñas de la especie y las grandes, se determinó que las pequeñas serían indicadoras del predominio de agua dulce y las grandes del predominio de agua marina. Debido a que las células pequeñas y grandes de A. normanii son generadas en el mismo ciclo de vida de esta especie, no se consideraron las formas o variedades subsalsa y normanii. Los resultados permiten concluir que A. normanii puede ser utilizado como indicador de la variabilidad salina de los cuerpos de agua.

Abstract Two studies on the phytoplankton and the physical and chemical characteristics of the Ciénaga Grande de Santa Marta (CGSM) lagoon in the Colombian Caribbean, carried out in 1987 and 1995, found that salinity has been a key factor in the variation of the cell diameter of the diatom Actinocyclus normanii. Small cells are produced when salinity is low, while big ones are produced when salinity is higher. In turn, salinity variations are determined by precipitation: during the rainy season salinity decreases while it increases during the dry season. Small cells are produced by asexual reproduction during the rainy season. Bigger cells result from sexual reproduction and the production of auxospores, normally when salinity concentrations are above 8 PSU and up to 30 PSU. Bio-essays in the lab have confirmed that auxospores were not formed at 2.8 PSU salinity concentrations but they did at 10 and 20 PSU concentrations. To prove the use of cell diameter in paleoenvironmental reconstructions, 300 valves of A. normanii were measured in 15 diatom slides from a 6 m sedimentary core extracted from the lagoon in front of Sevilla River (río Frío) in October 2010. The core interval selected (5 to 265 cm) represents approximately the last 2,300 years before present (BP). Statistical analyses indicated that the diameter of 40 µm marked the division between small and bigger cells. Diameters under 40 µm indicated fresher water conditions, and those larger than these, more saline conditions. Due to the relationship between small and bigger cells of A. normanii and taking into consideration that they are part of the same life cycle of this species, forms and varietes subsalsa and normanii were not considered. We concluded that variations in the diameter of A. normanii were dependent on salinity concentrations.

RESUMO Reservatórios têm sido construídos em todo o mundo para regularização de vazões, com vistas à melhoria de condições de uso dos recursos hídricos de bacias hidrográficas para diferentes propósitos, como abastecimento humano e industrial, irrigação e geração de energia elétrica. Águas de rios e córregos, que transportam nutrientes em excesso provenientes de esgotos sanitários e fertilizantes, quando represadas, podem estar sujeitas a grandes alterações qualitativas decorrentes de processos de eutrofização. Diversos índices foram criados por pesquisadores para classificação de estados de trofia de corpos d’água. No presente estudo foram analisados e comparados três índices de estado trófico (IETs) a partir da aplicação aos reservatórios da Pequena Central Hidrelétrica de Rio Bonito e da Usina Hidrelétrica Suíça, localizados na bacia do Rio Santa Maria da Vitória, no estado do Espírito Santo, considerando resultados de monitoramentos de qualidade de água em 20 campanhas realizadas entre outubro de 2008 e julho de 2014. Os reservatórios recebem aporte de nutrientes provenientes de esgotos domésticos, cultivos agrícolas e granjas. Foram considerados, especificamente, índices desenvolvidos por Carlson (1977), Lamparelli (2004) e Cunha, Calijuri e Lamparelli (2013). Concluiu-se que diferentes modelos podem resultar em classificações de estado trófico muito diferentes. O modelo de Carlson (1977), desenvolvido para reservatórios de clima temperado, resultou em classificação mais rigorosa, classificando os reservatórios principalmente como eutróficos e mesotróficos. Os modelos de Lamparelli (2004) e Cunha, Calijuri e Lamparelli (2013), desenvolvidos para reservatórios de clima tropical/subtropical, apresentaram resultados mais próximos, classificando os reservatórios principalmente como oligotróficos. Concluiu-se também que a sazonalidade e as precipitações pluviométricas nas bacias hidrográficas dos reservatórios podem influenciar de forma muito significativa os parâmetros de qualidade de água e a classificação do estado trófico de reservatórios. A grande variedade de classes de estado trófico escolhidas a partir dos diferentes modelos indica a importância da escolha adequada de modelos e índices, de acordo com as condições prevalentes nos corpos hídricos de interesse.

ABSTRACT Reservoirs have been built worldwide to regularize flows for improvement of watersheds water resources use conditions for different purposes, such as human and industrial supply, irrigation and power generation. Waters of rivers and streams that carry excessive nutrients from sewage and fertilizers, when dammed, may be subject to significant qualitative changes resulting from eutrophication processes. Several indexes have been created by researchers for trophic state classification of water bodies. In this study three trophic state indexes (TSIs), developed by Carlson (1977), Lamparelli (2004) and Cunha, Calijuri and Lamparelli (2013), were analyzed and compared, through the application to two power plant reservoirs, denominated Rio Bonito and Suíça, located in the Santa Maria da Vitoria river watershed, Espírito Santo state, Brazil. Results from 20 water quality monitoring campaigns were considered, conducted between October 2008 and July 2014. The reservoirs receive nutrient loads originated from domestic sewage, agricultural crops and chicken farms. It was concluded that application of different models may result in very different trophic state class definition. The application of the Carlson model (1977), developed for temperate climate reservoirs, resulted into higher eutrophic class level, classifying the reservoirs mainly as eutrophic and mesotrophic. Lamparelli (2004) and Cunha, Calijuri and Lamparelli (2013) models, developed for tropical/subtropical climate reservoirs, presented closer results, classifying the reservoirs mostly as oligotrophic. It was also concluded that seasonality and rainfall in reservoirs catchment areas may influence very significantly the reservoirs water quality parameters and trophic state classification. The wide variety of trophic classes chosen for the reservoirs, in this work, indicates the importance of the proper choice of models and indexes, according to the prevailing conditions in the water bodies of interest.