La agricultura familiar es uno de los sectores productivos más perjudicados por las dificultades de acceso, uso y aprovechamiento del agua. Aunque existe una gran diversidad de tecnologías que permiten mejorar esta situación, en ocasiones no están documentadas o la información se encuentra dispersa. Presentamos el Inventario de tecnologías de manejo de agua para la agricultura familiar, que recopila 42 tecnologías sostenibles y de bajo costo que se implementan en distintos países de nuestra América.

O monitoramento da qualidade da água é fundamental para a elaboração de uma base de dados confiável e adequada para fins de planejamento e gestão dos recursos hídricos e, neste contexto, os projetos de redes de monitoramento qualitativo em bacias hidrográficas têm se tornado cada vez mais relevantes. Bem projetada, uma rede de monitoramento identifica problemas de qualidade da água ao mesmo tempo em que estabelece valores de referência para a análise de tendências de curto e longo prazos. Entretanto, a ausência do planejamento da rede com base em métodos científicos pode acarretar no desperdício de recursos humanos, financeiros e logísticos, uma vez que estações de monitoramento podem ser instaladas em locais inadequados, ocasionado a geração de dados redundantes e pouco representativos. Sendo assim, o objetivo geral do presente estudo foi estruturar uma metodologia para avaliação, otimização e instalação de redes de monitoramento da qualidade da água. Todo o estudo foi realizado na porção mineira da bacia do rio Doce. No primeiro capítulo é demonstrada a aplicação de um conjunto de técnicas estatísticas multivariadas (Análise de Cluster e Análise Fatorial/Análise de Componentes Principais) com o objetivo de identificar as principais variáveis de qualidade da água a serem priorizadas nas campanhas de monitoramento, as suas possíveis fontes de poluição, bem como a melhor frequência de amostragem. Com os resultados identificou-se que as variáveis selecionadas pelas análises representam a alta susceptibilidade que a bacia do rio Doce apresenta à erosão, ao lançamento de efluentes domésticos nos corpos hídricos da bacia e à contaminação por metais pesados oriundos de atividades industriais e de mineração. Foram identificadas 14 variáveis como prioritárias na rede de monitoramento, sendo elas: clorofila a, coliformes totais, condutividade elétrica, demanda bioquímica de oxigênio, Escherichia coli, feofitina a, ferro dissolvido, fósforo total, manganês total, nitrogênio amoniacal total, oxigênio dissolvido, sólidos em suspensão totais, sólidos totais e turbidez. Os resultados também mostraram que a variação da qualidade da água do rio Doce é determinada, em parte, pela sazonalidade, reiterando a importância da frequência de monitoramento mensal nas estações da bacia do rio Doce. No segundo capítulo foram utilizadas técnicas estatísticas para analisar a tendência temporal e espacial (testes de Mann-Kendall, Sazonal de Mann-Kendall, correlação de Spearman na análise temporal e Análise de Cluster na análise espacial) dos dados de qualidade da água. Utilizando o Índice de Qualidade das Águas e as variáveis que o compõe, foi possível analisar a variabilidade da qualidade da água ao longo dos anos de monitoramento, identificando as áreas mais impactadas e as principais estações de monitoramento a serem mantidas na rede. Com os resultados das análises de tendência temporal identificou-se que a maior parte das estações que apresentaram tendências de redução na qualidade da água estão localizadas em áreas com adensamento populacional, demonstrando a forte influência das péssimas condições sanitárias dos municípios na qualidade da água da bacia. Na análise de tendência espacial, a análise de cluster agrupou as estações de monitoramento em seis clusters com base na sua similaridade entre os valores da qualidade das águas e, juntamente com os resultados das outras análises, verificou-se que a bacia do rio Caratinga apresentou o maior grau de poluição. Também foi possível apontar cinco estações que podem ser realocadas ou desativadas. Por fim, no terceiro capítulo, foi apresentada uma proposta metodológica para subsidiar a alocação de estações de monitoramento qualitativo. O método levou em consideração oito critérios relevantes ao monitoramento da qualidade da água em bacias hidrográficas brasileiras, sendo totalmente executado em ambiente de sistema de informação geográfica e aplicado em locais que possuem ou não redes de monitoramento já instaladas. Como a parte mineira da bacia do rio Doce já possui uma rede de monitoramento com 65 estações em operação, foi proposta uma expansão da rede e também realizada a simulação de um cenário considerando que a área não possuía uma rede já instalada. Com a aplicação da metodologia, sete novos locais foram propostos a fim de que a área de estudo possuísse a densidade recomendada pela Agência Nacional de Águas (ANA), sendo constatado que a Unidade de Gestão de Recursos Hídricos do rio Caratinga (UGRH5 Caratinga) possui a maior deficiência de estações dentre as seis unidades avaliadas na parte mineira da bacia do rio Doce. Na simulação do cenário considerando a não existência de rede, o mapa de adequabilidade obtido foi comparado com a atual rede de monitoramento e foi possível classificar as estações conforme a finalidade para qual foram instaladas, tais como: monitorar ambientes sob impacto de atividades antrópicas ou estabelecer padrões de referência para os corpos hídricos. | The monitoring of water quality is critical to the development of a reliable and adequate data base for planning and management of water resources. In this context, projects of networks for qualitative monitoring in river basins have become increasingly relevant. A well-designed, monitoring network identifies water quality problems while establishing benchmarks for analyzing short- and long-term trends. However, the lack of network planning based on scientific methods may result in a waste of human, financial and logistical resources, since monitoring stations can be established in inappropriate places, causing the generation of redundant and unrepresentative data. Thus, the general objective of the present study was to structure a methodology for evaluation, optimization and establishment of water quality monitoring networks. The whole study was carried out in the Minas Gerais portion of the Doce river basin. It is demonstrated in the first chapter the application of a set of multivariate statistical techniques (Cluster Analysis and Factor Analysis/Principal Component Analysis) with the objective of identifying the main water quality variables to be prioritized on the monitoring campaigns, their potential sources of pollution as well as the best sampling frequency. It was identified from the results that the variables selected by the analysis, represent the high susceptibility of the Doce river basin to erosion, domestic effluents release into its water bodies and heavy metals contamination coming from industrial and mining activities. A total of 14 variables were identified as priority variables in the monitoring network: chlorophyll a, total coliforms, electrical conductivity, biochemical oxygen demand, thermotolerant coliforms, pheophytin a, dissolved iron, total phosphorus, total manganese, total ammoniacal nitrogen, dissolved oxygen, total suspended solids, total solids and turbidity. The results also showed that the water quality variation of the Doce River is determined in part by the seasonality, emphasizing the importance of monthly monitoring in the stations of the Doce river basin. Statistical techniques were used in the second chapter to analyze the temporal and spatial water quality trend (Mann-Kendall trend test, Seasonal Mann-Kendall trend test, Spearman’s rank correlation coefficient on the temporal analysis and Cluster Analysis on spatial analysis). The use of Water Quality Index and the variables that compose it, made possible to analyze the variability of water quality over the years of monitoring, identifying the most impacted areas and the main monitoring stations to be maintained in the network. The results of time trend analysis made possible to find out that most of the stations that presented a decreasing tendency in water quality are located in areas with population densification, indicating the strong influence of poor sanitary conditions of the cities to the basin water quality. In the spatial trend analysis, the cluster analysis grouped the monitoring stations into six clusters based on the similarity of the water quality values. Along with the results of the other analysis, it was verified that the Caratinga river basin presented the highest pollution degree. It was also possible to point out five stations that can be relocated or deactivated. Finally, in the third chapter, a methodological proposal was presented to subsidize the allocation of qualitative monitoring stations. The method took into account eight criteria that are relevant to the monitoring of water quality in the river basins in Brazil, being fully executed in a geographic information system condition and performed in locations whether monitoring networks have been established or not. Since the Minas Gerais portion of the Doce river basin already has a monitoring network with 65 stations in operation, it was proposed to expand the network and also a scenario was simulated considering that the area did not have an already established network. As the methodology was applied, seven new sites were proposed so that the study area had the density recommended by the National Water Agency (Agência Nacional de Águas - ANA), and it was verified that the Caratinga River Water Resources Management Unit (Unidade de Gestão de Recursos Hídricos do Rio Caratinga - UGRH5 Caratinga) has the least number of stations among the six units evaluated in the Minas Gerais portion of the Doce river basin. Considering the non-existence of a network, in the scenario simulation, the adequacy map obtained was compared with the current monitoring network and it was possible to classify the stations according to the purpose for which they were established, such as: monitoring environments under anthropic activities or establishing standards for water bodies.

In the last years, in the semi-arid central region of Argentina, the increase of C3 non-palatable native grass species known generally as “pajas” was observed. One possible cause of the success of these species is the increase in rainfall observed in the region in recent years. The objective of this work was to evaluate the effect of a greater water availability and its seasonal distribution on the biomass and the production of reproductive structures of a non-palatable and highly invasive C3 species (Jarava ichu) and a non-palatable C4 species (Setaria lachnea). For this, a greenhouse experiment was carried out, consisting in manual irrigation of individuals of both species in pots. Treatments were: dry year, wet year with autumnal peak and wet year with spring peak. The increase in water availability favored the biomass of leaves and stems of J. ichu, independently of the seasonal distribution, with respect to the dry year. On the contrary, the biomass of S. lachnea did not respond to the different treatments (P>0.05). Likewise, the number of panicles was greater for J. ichu under the wet year treatment with spring peak, but there were no differences for S. lachnea.https://doi.org/10.25260/EA.19.29.1.0.763 | En los últimos años, en la región semiárida central argentina se observó el incremento de especies gramíneas nativas no palatables C3 conocidas generalmente como “pajas”. Una causa posible del éxito de estas especies es el aumento de las precipitaciones observado en la región en los últimos años. El objetivo de este trabajo fue evaluar el efecto de una mayor disponibilidad de agua y su distribución estacional sobre la biomasa y la producción de estructuras reproductivas de una especie C3 no palatable y altamente invasiva (Jarava ichu), y una especie C4 no palatable (Setaria lachnea). Para ello se realizó un ensayo en invernáculo que consistió en riego manual de individuos de ambas especies en macetas. Los tratamientos fueron: año seco, año húmedo con pico otoñal y año húmedo con pico primaveral. El aumento de la disponibilidad de agua favoreció la biomasa de hojas y tallos de J. ichu independientemente de la distribución estacional, con respecto al año seco. Por el contrario, la biomasa de S. lachnea no respondió a los distintos tratamientos (P>0.05). Asimismo, el número de panojas fue mayor para J. ichu bajo el tratamiento año húmedo con pico primaveral, pero no se detectaron diferencias para S. lachnea.https://doi.org/10.25260/EA.19.29.1.0.763

El presente proyecto comprende la evaluación de la calidad del agua del sistema de abastecimiento y conducción de la Junta Administradora de Agua Potable de Tambillo, a través de recorridos de campo, toma de fotografías del sistema de distribución de agua potable, recolección y análisis de muestras de agua que son destinadas para consumo humano de la población de la parroquia de Tambillo. Se inició el proyecto con una visita para el reconocimiento del lugar y toma de fotografías con el objetivo de conocer y evaluar las condiciones de dicho sistema. Se realizaron adicionalmente cuatro visitas de campo más, para la recolección de muestras correspondientes para los análisis establecidos tanto in situ como en laboratorios acreditados. Se empezó el muestreo en la vertiente Curipogyo (captación), para continuar con las tres plantas de tratamiento y finalmente con domicilios pertenecientes. Los resultados obtenidos además se evaluaron y compararon con las normas establecidas en base al cumplimiento de los límites máximos permisibles (LMP), las cuales son: Texto Unificado de Legislación Secundaria del Medio Ambiente (TULSMA) Libro VI, Anexo 1, Tabla 2; y la Norma INEN 1108:2011, la cual establece los requisitos que debe cumplir el agua potable para consumo humano. | This project includes the evaluation of the water quality in the conduction and supply system of Junta Administradora de Agua Potable de Tambillo, through field trips, taking photographs corresponding to potable water distribution system, collecting and analyzing samples of water that are destined to drinking of the population of the parish of Tambillo. The project began with a visit to recognize the place and take photographs with the objective of knowing and evaluating the conditions of this system. Four additional field visits were also made to collect the corresponding samples for the analyzes established both in situ and in accredited laboratories. Sampling was started on the Curipogyo slope (collection of the system), to continue with the three treatment plants and finally with households belonging to the distribution system. The results obtained were also evaluated and compared with the norms established based on compliance with the maximum permissible limits (LMP), which are: Texto Unificado de Legislación Secundaria del Medio Ambiente (TULSMA) Libro VI, Anexo 1, Tabla 2; and INEN 1108: 2011, which establishes the requirements that drinking water must meet for human consumption. | Jaramillo Sánchez, Luis Ángel, director

Endotherms dissipate heat to the environment to maintain a stable body temperature at high ambient temperatures, which requires them to maintain a balance between heat dissipation and water conservation. Birds are relatively small, contain a large amount of metabolically expensive tissue, and are mostly diurnal, making them susceptible to physiological challenges related to water balance and heat dissipation. We compiled total evaporative water loss (TEWL) measurements for 174 species of birds exposed to different temperatures and used comparative methods to examine their relationships with body size, ambient temperature, precipitation, diet, and diel activity cycle. TEWL in the thermoneutral zone (TNZ) was associated primarily with body mass and activity phase. Larger and more active-phase birds, with their higher metabolic rates, lost more water through evaporation than smaller, resting-phase birds, particularly at higher thermal exposures. However, maximum temperature of the natural habitat became an important determinant of TEWL when birds were exposed to temperatures exceeding the TNZ. Species from hotter climates exhibited higher TEWL. Adaptation to arid climates did not restrict evaporative water loss at thermal conditions within the TNZ, but promoted evaporative water loss at exposures above the TNZ. The TEWL of granivores, which ingest food with low water content, differed little from species with other food habitats under all thermal conditions. The effects of environmental covariates of TEWL were dissimilar across thermal exposures, suggesting no evidence for a tradeoff between water conservation in the TNZ and heat dissipation at exposure to higher temperatures. Thus, birds may be able to acclimate when climate change results in the need to increase heat dissipation due to warming, except perhaps in hot, arid environments where species will need to depend heavily upon evaporative cooling to maintain homeothermy.

El acuífero freático es la única fuente de agua para consumo humano en puestos del Salar de Pipanaco, Pomán, provincia de Catamarca. El objetivo es determinar la calidad química del agua utilizada para bebida por las poblaciones de los parajes: Taco Suna, San Jerónimo, Tucumanao, Balde de la Pampa, San Nicolás, Puesto Corazón de Jesús, San Roque, Maderera de San Antonio y Zapi Cruz, ubicados en el Salar de Pipanaco y su relación con los aspectos hidrogeológicos del área. Se determinaron las concentraciones de iones mayoritarios y minoritarios, se caracterizó geoquímicamente la calidad del agua utilizando los diagramas de Schoeller y Piper, se evaluó su aptitud en función del CAA y la OMS y se analizaron antecedentes hidrogeológicos del Salar de Pipanaco. La magnitud de exposición de las personas a enfermedades de origen hídrico es alta ya que las concentraciones de fluoruro, arsénico y sulfato superan los límites para consumo humano fijados por las normativas consultadas. | The freatic aquifer is the only source of water for human consumption at posts in the Salar de Pipanaco, Pomán, province of Catamarca. The objective is to determine the chemical quality of the water used for drinking by the populations of the places: Taco Suna, San Jerónimo, Tucumanao, Balde de la Pampa, San Nicolás, Puesto Corazón de Jesús, San Roque, Maderera de San Antonio and Zapi Cruz, located in the Salar de Pipanaco and its relationship with the hydrogeological aspects of the area. The concentrations of major and minor ions were determined, water quality was geochemically characterized using the Schoeller and Piper diagrams, their aptitude was evaluated according to the CAA and the WHO and hydrogeological antecedents of the Salar de Pipanaco were analyzed. The magnitude of exposure of people to hydric origin diseases is high since the concentrations of fluoride, arsenic and sulfate exceed the limits for human consumption set by the regulations consulted. | Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES)

In order to define the trophic interactions in the Caimito swamp complex (municipality of Caimito, department of Sucre 84°7'42.29''N-75°06'48.59''O) and between this and the adjacent ecosystems, the biological communities present were studied. We used the information obtained in previous studies, one in high water period and one in low water period and a sampling of the authors, during the high water period. In each of them, the biotic richness of the body of water and the surrounding environment was studied, the biotic groups were: birds, aquatic macrophytes, aquatic macro invertebrates, fish, zooplankton and reptiles. A list was made of the species and taxonomic groups found, and trophic species were established, which served as the basis for the construction of the food web. The important role of detritus as a source of energy was evidenced in this ecosystem. Most representative groups were the omnivorous fish and the aquatic macro invertebrates, whose broad trophic spectrum and mechanisms for obtaining food make them vital groups in the use of matter and energy and transport to higher trophic levels. The food webs that represent the periods of drought and flood are functionally and structurally different. In period of drought, the community is dependent on detritus and primary producers participate during the flood. | Con el objetivo de definir las interacciones tróficas en el complejo cenagoso de Caimito (municipio de Caimito, departamento de Sucre 8°47'42,29''N- 75°06'48,59''O) y entre este y los ecosistemas adyacentes, se estudiaron las comunidades biológicas presentes. Se utilizó la información obtenida en estudios previos, uno en periodo de aguas altas y uno en periodo de aguas bajas y un muestreo de los autores, durante el período de aguas altas. En cada uno de ellos se estudió la riqueza biótica del cuerpo de agua y el ambiente aledaño, los grupos bióticos estudiados fueron: aves, macrófitas acuáticas, macroinvertebrados acuáticos, peces, zooplancton y reptiles. Se hizo un listado de las especies y grupos taxonómicos hallados y se establecieron trofoespecies, con las que se realizó una matriz binaria de datos, que sirvió de base para construir la red trófica. Se evidenció el papel importante de los detritos, como una fuente de energía en este tipo de ecosistemas. Los grupos más representativos fueron los peces omnívoros y el conjunto de macro invertebrados acuáticos, cuyo amplio  espectro trófico y mecanismos de obtención del alimento, los convierte en grupos vitales en el aprovechamiento de materia y energía y transporte a los niveles tróficos superiores. Las redes tróficas que representan los períodos de sequía e inundación son funcional y estructuralmente diferentes. En el periodo de sequía, la comunidad es dependiente del detritus y en la inundación participan los productores primarios.

Expone la disputa del agua entre Ica y Huancavelica y el desarrollo del proceso de conformación de la mancomunidad entre estas regiones, así como los principales desafíos que afrontan.