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Background: Cannabis plants and their seed have been used in many cultures as a source of medicine and feeding during history. Today, there is an increasing demand for cannabis seeds for medical use. Moreover, a seed sales market with no legal regulations has also grown. This may pose some issues if a quality control is not set in place. Identification of cannabis strains is important for quality control purposes in a nonregulated growing market and in cases of illegal traffic and medical use. Owing to the high price as a pharmacological drug, commercial products of cannabis plants and seeds for medical users are often subjected to adulterations, either when packing or distributing certified seeds in the market. Materials and Methods: Cannabis commercial seeds and cannabis seeds for medical use were analyzed with high-resolution melting (HRM) analysis using barcoding markers. Humulus lupulus L. plants from a local market were used as outgroup control. DNA barcoding uses specific regions of the genome to identify differences in the genetic sequence of conserved regions such as internal transcribed spacer (ITS) and rbcL. DNA barcoding data can be generated with real-time polymerase chain reaction combined with HRM analysis to distinguish specific conserved DNA regions of closely related species. HRM analysis is the method of choice for rapid analysis of sequence variation. Results: The melting temperature (Tm) of homogeneous packages was consistent with single genotypes. However, packages containing contaminating seeds showed Tm differences of 0.2°C on average. Conclusions: An effective, rapid, and low-cost method based on ITS nuclear DNA and on chloroplast rbcL regions for screening and detection of contamination in commercial cannabis seeds was developed and applied for the analysis of different samples. This approach can be used as a quality control tool for cannabis seeds or other plant material.

Galaxias maculatus aquaculture objectives is to produce millions of eggs. Wild females are small (2 g), have quick sexual maturity and low mean fecundity (500 eggs/female), requiring larger fishes with higher fecundity. This study aim is to evaluate experimentally the effect of the levels of protein, lipid and dietary energy on weight increases in adults. Five independent experiments were performed at different sequential time periods at the UCT hatchery, Chile. Specimens were obtained from a) Crystalline sea return specimen catches in the Tolten estuary (4 -6 cm, 0.3-0.4 g.). b) Hatchery cultured fish. Fish were fed by hand ad libitum. In experiments 1 to 4, pelleted diets were prepared with 3 to 5 levels of protein (treatments 27 up to 57%), crumble size, three 100 L fibre ponds replicates. In experiment 5 the effect of two lipid levels (8 and 21%) was evaluated with commercial extruded Salmon Nutra Starter isoproteic crumble 1 diet at 63%, replicated in 4 ponds. The results show: A tendency to increased weight in all sizes with an increased protein level in the pelleted diet.A maximal adult growth is obtained with a diet containing a minimum of 37% crude protein, with 40% the optimal value. A higher % protein in the diet or growth in weight lower feed conversion ratio. The feed conversion ratio in the extruded diet reaches up to 0.5 and in the pelleted vary from 0.7 to 1.5. Fish 0.6 g fed with 63% protein, extruded commercial diet with two different lipid levels (8 and 21%, 20.40 and 23.84 MJ kg-1, PE/TE 0.62 and 0.71) increased weight the first month 67 and 105% each. It has been established that high-energy diets with optimal levels of protein and lipid are a good short-term solution to obtain G. maculatus of higher weight. Resumo O objetivo da aquicultura de Galaxias maculatus é produzir milhões de ovos. As fêmeas selvagens são pequenas (2 g) e têm maturidade sexual rápida e fecundidade média baixa (500 ovos/fêmea), necessitando de peixes maiores e com fecundidade superior. O objetivo deste estudo é avaliar experimentalmente o efeito dos níveis de proteínas, lipídios e energia da dieta sobre o aumento de peso em adultos. Cinco experimentos independentes foram realizados em diferentes períodos sequenciais de tempo no incubatório UCT, Chile. Os espécimes foram obtidos a partir de: a) capturas de espécimes de retorno do mar cristalino no estuário de Tolten (4-6 cm, 0,3-0,4 g); b) peixes de cultura em incubatório. Os peixes foram alimentados à mão ad libitum. Nos experimentos de 1 a 4, dietas peletizadas foram preparadas com três a cinco níveis de proteína (tratamentos 27 a 57%), tamanho do crumble, três repetições de tanques de fibra de 100 L. No experimento 5, o efeito de dois níveis de lipídios (8 e 21%) foi avaliado com dieta comercial isoproteica crumble 1 de Salmon Nutra Starter extrusada a 63%, replicada em quatro tanques. Os resultados mostram: uma tendência ao aumento de peso em todos os tamanhos, com um aumento do nível de proteína na dieta peletizada; um crescimento adulto máximo com uma dieta contendo um mínimo de 37% de proteína bruta, com 40% do valor ideal; uma porcentagem maior de proteína na dieta ou crescimento em peso com menor taxa de conversão alimentar. A taxa de conversão alimentar na dieta extrusada chega a 0,5, e na peletizada varia de 0,7 a 1,5. Peixes de 0,6 g alimentados com 63% de proteína e dieta comercial extrusada com dois níveis lipídicos diferentes (8 e 21%; 20,40 e 23,84 MJ kg-1; PE / TE 0,62 e 0,71) aumentaram de peso no primeiro mês em 67 e 105% cada, respectivamente. Foi estabelecido que dietas de alta energia com níveis ótimos de proteínas e lipídios são uma boa solução de curto prazo para obter G. maculatus de peso mais alto.

espanolEn los ecosistemas, las fluctuaciones estacionales en la disponibilidad de recursos pueden tener efectos en especies con requerimientos troficos similares, lo cual aumenta la probabilidad de que surja la competencia interespecifica. Esta situacion se hace mas evidente en ambientes antropizados, donde la homogeneizacion del espacio puede agudizar la escasez de recursos y modificar el comportamiento alimentario en un grado incierto. De esta manera, resulta de especial interes entender como estas especies modifican sus habitos alimentarios en un contexto de transformacion del habitat. Evaluamos la diversidad de presas y el solapamiento de dos depredadores, el zorro chilla, Lycalopex griseus, y la lechuza blanca o lechuza comun, Tyto alba, durante tres estaciones en 2018 (invierno, primavera y verano). Se utilizaron heces y egagropilas recolectadas en un paisaje con predominancia agricola en el centro y sur de Chile. En el caso del zorro chilla, se observo un perfil trofico generalista, ya que consumio una amplia variedad de presas, en la que predominaron los lagomorfos y en menor medida, los roedores. En cambio, la lechuza concentro una gran proporcion de su perfil alimentario a los pequenos roedores, con pequenas variaciones entre estaciones. El analisis del solapamiento de las dietas mostro variaciones durante los periodos estudiados, con un valor maximo en invierno y uno minimo en primavera. La variacion en el consumo de presas en funcion de su tamano facilitaria la coexistencia de ambas especies en la zona de estudio. EnglishIn ecosys-tems, seasonal fluctuations in the availability of resources can promote effects on species with similar trophic requirements, increasing the probability of interspecific competition. This scenario becomes more evident in human–dominated landscapes where homogenization of space can contribute to the shortage of resources, modifying species feeding behavior to an uncertain degree. Understanding how these species modify their feeding habits within the context of habitat transformation is of special interest. We evaluated the diversity of prey and overlap for two predators, the chilla fox Lycalopex griseus and the barn owl Tyto alba, during three seasons in 2018 (winter, spring and summer). The study was based on the analysis of feces and pellets in a landscape with agricultural predominance in Southern–central Chile. We found the chilla fox had a generalist dietary profile, feeding on a broad spectrum of prey, with predominance of lagomorphs and, to a lesser extent, rodents.In contrast, the diet of the barn owl mainly consisted of small rodents, with little variation across sea-sons. Analyses of dietary overlap showed fluctuations during the periods surveyed, with a maximum value in winter and a minimum value in spring. Variations in the consumption of prey based on their size could facilitate their coexistence in the study area.

The Environmental Impact Assessment (EIA) is a legal and administrative tool aimed to identify, predict, and interpret the impact of a project or activity on the environment and human health. The EIA also evaluates the accuracy of the predictions and audits the effectiveness of the established preventive measures. Regarding the sanitation sector, efficiency of wastewater treatments and sanitation networks determine the pollutant level of the discharged liquid effluents and the subsequent impact on the environment and human health. This problematic makes necessary to assess how proper the regulatory follow-ups of sanitation projects is. This paper evaluates the performance of the Chilean EIA System concerning to sanitation projects. Taking into account that the more restrictive Environmental Impact Study (EIS) and more permissive Environmental Impact Declaration (EID) are the ways for projects’ entry to the EIA System in Chile, 5336 sanitation projects submitted to EIA between 1994 and 2019 were complied. A representative sample of 76 projects (15 entered as EIS and 61 as EID) was analyzed by using a principal coordinate analysis (PCoA) through 14 selected performance indicators. Observed weaknesses have led to propose improvement opportunities of the EIA focused on the follow-ups after the environmental license is obtained, such as creation of a simplified sanctioning procedure, decentralization of decision-making, deadline establishment in each stage, and unified direct link for each project. These proposals seek to improve the effectiveness of monitoring and possible sanctions to early identify impacts of sanitation projects on the environment and human health. This paper introduces a robust methodology for evaluation criteria focused on the follow-ups analysis, which can be used in other countries that consider respectful sanitation projects have direct social and environmental benefits leading to long-term indirect cultural and economic values.

In Chile, salt (NaCl) use per salmon fish farm ranges between 20-30 t yr(-1) and is used to prevent and control fungal infections. An increase in salinity in freshwater can have adverse effects on freshwater biodiversity and ecosystem functions and services. We studied the effects of fish-farm effluents on benthic macroinvertebrate communities in a northern Patagonian stream (Chile). Benthic samples were collected at 3 sites near a land-based salmon aquaculture facility (one located 100 m upstream from the fish-farm outlet for effluent, 2 sites located 200 and 400 m downstream from the effluent source). We found changes in benthic macroinvertebrate communities downstream from the effluent, with higher abundances of tolerant taxa and lower abundances of sensitive taxa, which was related to nutrient and salt concentration in the water. We also studied the effects of salinity on macroinvertebrate drift in a mesocosm experiment conducted in recirculating channels, measuring the drift of 2 salt-sensitive macroinvertebrates (Andesiops peruvianus and Smicridea annulicornis), collected from an unpolluted northern Patagonian stream, after exposure to a range of salinity concentration pulses similar to those from fish farms. Our results demonstrate that (1) fish-farm effluent can alter stream macroinvertebrate community composition and dynamics, and (2) such effects are at least partly driven by high salt concentrations in effluent waters. We thank the vice rectory for research and postgraduate studies at the Catholic University of Temuco and project MECESUP UCT 0804. The study was funded by the Fondecyt project 'Tracing organic pollution from land-based aquaculture systems in terms of fluorescence spectroscopy and assessment of ecotoxicological biomarkers in aquatic organisms in Southern Chile' (Ref. 1130132). L.B. was supported by the Spanish Ministry for Science, Innovation and Universities funds (Ref. RTI2018095023-B-I00) and Basque Government funds (Ref. IT95116) to the UPV/EHU Stream Ecology Group. Editorial

Background Forest ecosystems provide services that are important for human use; one of the most critical ecosystem services is the provision and regulation of water. Basins with high forest improves hydrological functionality by promoting reduction in surface runoff, increase infiltration and aquifer recharge, and ensures base flow regulation amongst others. On the other hand, the conversion towards highly anthropized productive systems is usually accompanied by precarious environmental management that alters the hydrological cycle and reduction in water quality in basins. Aim The goal of this study was to analyze land use changes and their effect on water efficiency index (WEI) in three sub-basins. Methodology The methodology included a multi-temporal analysis of satellite images to identify land uses, also the use of SWAT (Soil and Water Assessment Tool) model for hydrological analysis in each sub-basin, information needed for calculating the WEI. Results The results revealed the existence of no significant difference in terms of WEI between the sub-basins with predominant tree cover of native or artificial, being higher (0.89) than the WEI values reported by the sub-basin with agricultural land use (0.65). It is concluded that hydrological functions are more efficient in basins with forest cover, made up of native or exotic species, than agricultural land use with annual crop rotations. The results contribute to decision making on public policies associated to the rural productive activities. Concluded Finally, we conclude the necessity of the promotion of forest plantation management techniques that avoid clear-cutting and multiple rotations in basin headwaters and riparian areas.

In recent years, social and environmental conflicts concerning the aquaculture sector have increased. These conflicts arise from the different perception that individuals, collectives, private companies and the State have about the potential impacts of aquaculture on the environment and quality of life. The Environmental Impact Assessment (EIA) of aquaculture projects in Chile is the main administrative tool for decision-making, allowing identify, predict, and propose preventive measures to mitigate negative consequences of this growing sector. This article analyzes the performance of the EIA in Chile concerning aquaculture projects between 1994 and 2019. Of the 5323 projects entering the Chilean EIA during this period, the EIA system-performance analysis selected the 71 most representative. For a reliable comparative analysis, the selected projects were first classified in accordance with the active regulation within the period. Subsequently, 14 performance indicators were selected and similarities—by means of a principal coordinate analysis—were explored. Significant differences between the third (SD40) and the first two (SD30 and SD95) regulations were observed. Based on these results and considering demands of local communities and social leaders (who request continuous articulations among technical areas, administrative tools, and policies to increase the sustainability standards of aquaculture), four opportunities for improving the EIA in aquaculture projects are proposed: incorporation of synergistic and cumulative effects, adaptation to climate change, development of a general methodology, and incorporation of early citizen participation (in projects having environmental charge) increasing the performance and confidence of the EIA. The introduced methodology enables comparisons of the EIA process in different regulatory periods using indicators, serving as guidance to evaluate the performance of the EIA in aquaculture. This methodology can also be used by other aquaculture producing countries around the world.

Easy, economic, precise species authentication is currently necessary in many areas of research and diagnosis in molecular biology applied to conservation studies of endangered species. Here, we present a new method for the identification of three fox species of the Lycalopex genus in Chile. We developed an assay based on high‐resolution melt analysis of the mitochondrial cytochrome B gene, allowing a simple, low cost, fast, and accurate species determination. To validate the assay applicability for noninvasive samples, we collected fecal samples in the Atacama Desert, finding unexpectedly one species outside of its known distribution range. We conclude that the assay has a potential to become a valuable tool for a standardized genetic monitoring of the Lycalopex species in Chile.

The global aquaculture industry has grown exponentially in recent years using to control of infections and diseases, a variety of veterinary drugs (VMP) are used, including antibiotics, antifungals and antiparasitics, which have different routes of emission, environmental persistence and side effects to aquatic organisms, becoming one of the main concerns in its use of veterinary drugs (VMP) and its potential toxicological impact on the environment, in this context, Chile is considered one of the main salmon producers. Ecological risk assessment of active principles used infreshwater fish farms worldwide and in Chile were investigated. We recollect a physical - chemical properties of active principles used by fish farms and we could estimate the relative hazard a priori. Later active principles grouped as antibiotics (n = 6), antiparasitics (n = 5), anesthetics (n = 3), and disinfectants (n = 7) were assessed using a mass balance model based on fugacity was developed for each active principle under treatments via immersion and food administration in fish, while a volumetric model for disinfectants and sodium chloride was used for estimating the predicted environmental concentration (PEC), under a real smolt farming scenario in fish farms. Ecotoxicological data were collected from open literature to predict the no-effect concentration (PNEC). The ecological risk assessment was characterized using a risk quotient (RQ = PEC/PNEC) based in two assessment tiers. Results revealed that 12 active ingredients showed a high risk (RQ ≥ 1), thus indicating that adverse effects could occur and further investigation with measured concentrations in the field are required to reduce exposure in surface waters.

Extreme temperatures have increased in intensity, duration and frequency in the last century, with potential consequences on key ecological processes such as organic matter breakdown. Many stream ecosystems are fueled by the breakdown of terrestrial leaf litter, which is exposed to atmospheric conditions for certain periods of time before entering the stream. Thus, extreme warming or freezing events may affect the litter physicochemical structure, which could translate into altered breakdown within the stream. The above prediction was tested by exposing litter of common riparian tree species in southern Chile to freezing (−20 oC; dry or wet litter) or heating (40 oC) and comparing breakdown with control litter exposed to room temperature (20 oC), separating the effects of different breakdown agents (i.e., leaching, microorganisms and detritivores). The greatest effects were found in wet litter subjected to freezing; this treatment significantly increased leaching in the short term (48 h) and slowed down breakdown in the long term (30 days), mostly due to the inhibition of microbial breakdown. Heating also retarded microbial breakdown, but the effect was smaller. Our results suggest that short-term extreme temperatures—particularly cold ones—have the potential to slow down litter breakdown in streams, which will most likely impact global biogeochemical cycles where streams play a key role.

Indexación: Scopus. This work was supported by the FONDEF Project D06I 1024 “Development of technologies for the production of red cusk-eel fingerlings (Genypterus chilensis)”. Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in recent years due to overfishing. In the development of the farming technology, high mortalities were obtained during egg incubation. The objective of this study is to contribute to the knowledge of fecundity and eggs viability of G. chilensis in captivity. The spawns of G. chilensis were analyzed over a period of 2 years and 3 months. The total fecundity was estimated by counting the masses and eggs produced monthly throughout the period. The results confirm that G. chilensis is a partial spawner, since a female may more than two masses of eggs per day, due to a large amount of mass spawned per season (621 average). The total production of masses of the Farming Centre during the period was 2,290; of these, only 7% (166) corresponding to 15,330,517 eggs were incubated. Because of its high fecundity, G. chilensis produces numerous masses of eggs, of which only a small percentage reaches incubation, as well as it occurs in other marine fish. © 2018, Escuela de Ciencias del Mar. All rights reserved. https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0718-560X2018000200489

Decomposition of leaf litter is a fundamental process for the functioning of forested wetlands. The rapid increment of forest plantations has involved a greater contribution of leaf litter of exotic origin to these ecosystems. The decomposition rate between leaf litter of native and exotic origin in a forested wetland of the Mediterranean zone of Chile was compared, as well as the contribution of bacteria and macroinvertebrate to this process. It was determined that the decomposition rate of the leaf litter presented significant differences (p < 0.05) between species, being faster in those of non-native origin. This could be due to differences in ecophysiological aspects of the leaves like the presence of chemical compounds such as waxes or oils. Both analyzed communities were relevant in the studied process. However, bacteria contributed mostly to the decomposition of both types of leaves. The implications of the physical and chemical characteristics of the leaves and the water on the processing of the foliar material are discussed.

The inland waters of Chile hold endemic species of crustaceans, and these habitats are threatened at present due to pollution as a result of human activities. Until now, the environmental studies performed have not considered native species for evaluating environmental risks. The aim of the present study was to do a first culture experiment with the freshwater copepod Tumeodiaoptomus diabolicus that inhabits central and northern Chilean Patagonian lakes. The copepods were cultured under two dietary regimes, i.e., a diet of microalgae and an artificial diet. The experiment was conducted over 12 days, and the maximum growth was obtained with the artificial diet. The present results would agree with similar results obtained for pseudodiaptomid copepods, that are massively used for aquaculture activities. In accordance with the obtained results and published data in the literature, T. diabolicus culture could be relatively easily done, and would thus qualify as an assay for investigating environmental conditions.

The Cautin river is located in the Araucania region, Chile (38°S), and is characterized by alterations through human interference in its surrounding basin, by the presence of introduced salmonids, and by its mixed regime, which originates from melting snow in summer and rains in winter. The fauna of this river includes an invertebrate fauna composed of both endemic and widespread species, which has, however, been only poorly studied until now. The aim of the present study was to make a review of the ecological role of the benthic inland water crustaceans of the River Cautin, in order to understand their importance in the ecosystem of the river. The literature revealed the presence of abundant populations of amphipods and freshwater crabs as well as of aquatic insects along the river’s course. Many of these crustaceans are prey for both introduced salmonids and native fishes. Similar results have been reported for other southern Argentinean and Chilean Patagonian rivers.

The objective of this chapter was to obtain information about arsenic speciation in algae studied in American Continent and Antarctic. This matter supposes deliver information with respect to accumulation, biotransformation and toxic effect on human health. Arsenic speciation in algae has become one of the most important issues to assess the risk to human health associated with algae consumption. This chapter also include the main analytical methods for the determination of different chemical arsenic-species used commonly in American Continent and Antarctic. Finally, some countries of America Continent such as Argentina, Chile, Brazil among others, have carried out important studies on arsenic content in algae, mainly brown macroalgae. It is concluded, that is necessary to increase and pursue more researches about arsenic speciation in algae in American Continent and its effects on human health attributed to it consumption.

Background Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio-economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural characteristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the habitat. Methods We studied the green areas in the city of Temuco, southern Chile (Park, Square and Median strips of main streets), evaluating the variables: (a) surface area, (b) vegetation, (c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α (intra-environment) diversity and β diversity (between environments) and the statistical analysis identified the environmental variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird diversity. Results We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the origin (native) of shrub species. Conclusions The bird diversity varied significantly according to the type of urban green area. The environmental variables presenting significant correlations with bird diversity were: surface area, native species of shrub stratum, shrub cover, and bare soil area. The best multiple regression model showed that the three most important variables for bird diversity are the surface area of the green area, the cover of the shrub stratum and the presence of native shrub species.

In this study, we carried out a comparative analysis of the Chilean Environmental Impact Assessment (EIA) system using evaluation criteria compared against three countries to allow for an objective evaluation within the growing demand of society for a more creditable and trustable EIA system. A total of 18 evaluation criteria were selected from the literature, and four new criteria for comparing EIA systems were proposed. The Chilean EIA system was compared to that of Brazil, Spain, and Canada using the following four evaluation criteria categories: EIA Legislation (four criteria), EIA Administration (four criteria), EIA Process (eleven criteria), and After EIA (three criteria). A Hierarchical Agglomerative Cluster Analysis for assessing similarity among the EIA systems of Chile, Canada, and Spain was performed: the similarity being 88%. A Principal Component Analysis shows that only 13 of the selected 22 criteria contribute to the variability of the selected EIA systems. The main strengths of the Chilean EIA system are the existence of Specialized Environmental Courts for the resolution of disputes and Appeal options before execution. The identified weaknesses are an EIA system with high centralization at the national level, the absence of consideration of project alternatives, no requirement for scoping, and that the process of Strategic Environmental Assessment is not binding. Modifications to the Environmental Impact Assessment System Regulation are proposed by authors as feasible improvements particularly in relation to, Decentralization of the EIA system, Alternatives for design, Scoping incorporation, Register of reviewers of baseline information, and the public information process and post-evaluation. The method used seeks out to serve as guidance for countries with similar environmental and social contexts, as well as environmental legislation improvement needs.

Nothofagus dombeyi is distributed on very diverse sites in the temperate forests of Chile and Argentina. In Chile, studies on its dynamics and productivity in forests, where it is the dominant species, have been carried out mainly in the foothills of the Andes, but the productivity and growth of these forests in the Coastal Range are almost unknown. The objective of this study was to evaluate the construction of a single dominant height/age growth model for two homogeneous edaphoclimatic zones (ZEH 2 and 5) previously defined for this species in the Coastal Range of southcentral Chile. The results showed that the Chapman–Richards model was the best candidate function, in terms of goodness of fit and predictive capabilities. Using this function, specific parameters (a, b and c) were obtained for each zone, from which site models were constructed by the Algebraic Difference Approach method for a base age of 35 years. This model is intended to contribute to better estimations of site productivity for N. dombeyi forests in the Coastal Range of south-central Chile, and thus facilitate private and public decisions regarding their management.Keywords: coihue, edaphoclimatic zones, evergreen, management, temperate forests

The suitability of Mazzaella laminarioides and Sarcothalia crispata as heavy metal biomonitors of Cd, Cu, Hg, Pb, and Zn was assessed by comparing bioaccumulation of these elements in different life stages and frond sizes in samples from three locations, San Vicente Bay (industrial area), Coliumo, and Quidico (the latter as a reference station), where different degrees of heavy metal pollution are recorded. Bioaccumulation and bioconcentration factors of Cd, Cu, Hg, Pb, and Zn were evaluated. The two macroalgae species showed similar patterns, with higher values of Cu, Hg, Pb, and Zn in polluted areas. M. laminarioides bioaccumulated higher concentrations of all metals assessed than S. crispata, independent of life stage and frond size. The results also showed significantly higher Cu, Hg, Pb, and Zn concentrations (p

Los servicios ecosistémicos proveen variados beneficios a la sociedad. Dichos servicios han sido clasificados en cuatro categorías: servicios de provisión, regulación, soporte y culturales. Una de las principales brechas en el mapeo social y la espacialización de estos servicios, se relaciona con la ausencia de una metodología que integre variables biofísicas y perceptuales de actores relevantes en un territorio. El análisis espacial multicriterio (AEMC) constituye un marco metodológico apropiado que permite integrar esta información. La presente investigación tuvo como objetivo proponer y aplicar una metodología de análisis multicriterio, basado en herramientas SIG y unidades ambientales homogéneas (UAH) para el mapeo de servicios ecosistémicos en la subcuenca del río Quepe. Los resultados indicaron que los servicios de provisión, regulación y culturales, estuvieron significativamente presentes y asociados a la UAH bosque nativo. Por otro lado, el nivel de presencia de estos servicios fue significativamente menor en las UAH plantaciones y terrenos agrícolas. Se concluye que el método presenta la ventaja de otorgar facilidad y flexibilidad en la espacialización de datos, mientras que recoge de manera sencilla los valores perceptuales de los actores locales y cómo estos perciben el nivel de presencia de un determinado servicio en la subcuenca.

Galaxias maculatus is an osmeriform native ¢sh of the Southern Hemisphere, in which the crystalline larvae is considered as a luxury delicacy, for this reason, it has been commercially exploited in Chile, Argentina and New Zealand. However, the ¢sheries have been rapidly decreasing due to the overexploitation and the predation of introduced species. Because of these events, there is a need to determine a carrying capacity for an intensive ¢sh culture. In order to optimize stocking densities for ¢sh culture, this paper proposes objectives to determine oxygen consumption (OC) rates, dissolved oxygen concentrations that produce signs of hypoxia and the average time elapsed between food intake and peak OC in G. maculatus. In the oxygen experiments under routine metabolism conditions, we found that G. maculatus adults and whitebait showed signs of asphyxia at dissolved oxygen concentrations between 1.3 and 2.2 mg L � 1 and that adults tolerated dissolved oxygen levels as low as1.3 mg L � 1 . The results showed that G. maculatus individuals with an average weight of 0.04 g consumed 0.048 mg O2 h � 1 , whereas individuals with an average weight of 1.4 g consumed 0.345 mg O2 h � 1 . Galaxias maculatus increased the OC rate by 31%, from 0.39 to 0.51mg O2 h � 1 g � 1 , occurring 14 min after food intake. The carrying capacities for industrial cultures of G. maculatus, were estimated using an allometric equation (OC 50.2363 � W 0.612 ), a water £ow rate of 1m 3 h � 1 and an input oxygen concentration of 10 mg L � 1 at 12 1C. The density culture of whitebait (4 g) can be allowed to reach 8^11kg m � 3 ; therefore, these stocking densities reduce the risk of hypoxia and mortality, ensuring the appropriate growth and feed conversion rates.

Nothofagus dombeyi grows in a wide variety of sites. The information about its productivity is still scarce, which makes it difficult for foresters and landowners to take decisions about the best practices to maintain and/or improve the goods and services derived from the forest. The aim of this study was to construct dominant tree height functions and site index curves for secondary forests of Nothofagus dombeyi (coihue) in south-central Chile. We measured 100 sample units throughout three edaphoclimatic zones, and 300 dominant trees (three per plot) were used for stem analysis. Three non-linear growth models (Chapman–Richards, Weibull and Logistic) were fitted, and the best model for each edaphoclimatic zone corresponded to Chapman–Richards. In addition, it was determined that for each zone it was necessary to obtain a given growth model given the high variability of sites. The best tree height growth corresponded with zone 2, followed by zone 1 and zone 3. In zone 2 trees reach 31 m at age 60, 29 m in zone 1, and 24 m in zone 3, indicating variation in growth patterns and differences between zones. We recommend using the models for a range of ages between 10 and 60 years (base age 35 years). This is the first large-scale study describing growth of N. dombeyi for the southern part of South America in secondary forests where they occur as one of the most important, but least managed, forest resources in the region.Keywords: coihue, dominant height, evergreen, Nothofagus dombeyi, polymorphic, site indexSouthern Forests 2014, 76(4): 221–228

Nothofagus dombeyi grows in a wide variety of sites in Chile (30-47°S), but there is little knowledge about its productive potential. This lack of information hinders decision-making to better guide the production of goods and services from these forests. This study was conducted in central-southern Chile (39°S-41°S), where this species is prominent, especially in secondary forests. The aim of the study was to determine the homogeneous edaphoclimatic zones for secondary forests of N. dombeyi based on the integration of environmental factors. The methodological approaches considered the spatial analysis and construction of geographic covers using geographic information systems, principal components multivariate analysis, and clustering techniques with CART analysis. Five homogeneous zones could be determined for N. dombeyi with a high level of accuracy. The spatial distribution of N. dombeyi secondary forests was explained in decreasing order by climate, soil and topography. Nothofagus dombeyi crece en una amplia variedad de sitios en Chile (30-47 ° S), por ello existe escaso conocimiento sobre su potencial productivo. Esto dificulta la toma de decisiones que orienten de mejor forma la produccion de bienes y servicios de estos bosques. Este estudio se llevo a cabo en el centro-sur de Chile (39° S-41° S), donde esta especie es prominente, especialmente en bosques secundarios. El estudio tuvo como objetivo determinar zonas edafoclimaticas homogeneas para los bosques secundarios de N. dombeyi , basado en la integracion de factores biofisicos. Los enfoques metodologicos consideraron analisis espacial y construccion de coberturas geograficas por medio de sistemas de informacion geografica, analisis multivariado de componentes principales y tecnicas de agrupamiento con analisis CART. Fue posible determinar cinco zonas homogeneas para N. dombeyi con un alto nivel de precision. La distribucion espacial de la especie se explico en orden decreciente por los factores biofisicos clima, suelo y topografia.

The benthic fauna in northern Patagonian streams is characterized by presence of water quality indicator species. The aim of the present study was characterized the benthic communities in streams associated to sites with presence of Nothofagus forests and with human intervention without Nothofagus forests using null models in ecology, unified neutral theory of biodiversity (UNTB) and unweighted pair group method with arithmetic mean (UPGMA). The results of species co-occurrence null model revealed that species associations are random, whereas the results of niche overlap null models revealed the presence of niche overlap. The UNTB results revealed low species number. The results of UPGMA revealed that species composition is specific for each site existing marked differences. The exposed results agree with results observed for central and northern Patagonian Chilean rivers, where the species composition is variable in according to surrounding basin properties and seasonal conditions. RESUMO A fauna bentônica nos córregos do norte da Patagônia é caracterizada pela presença de espécies indicadoras de qualidade da água. O objetivo do presente estudo foi caracterizar as comunidades bentônicas em riachos associados a locais com presença de florestas de Nothofagus e com intervenção humana sem florestas de Nothofagus usando modelos nulos em ecologia, teoria unificada de biodiversidade unificada (UNTB) e método de grupo de par não ponderado com média aritmética (UPGMA). Os resultados do modelo nulo de co-ocorrência de espécies revelaram que as associações de espécies são aleatórias, enquanto os resultados de modelos nulos de sobreposição de nicho revelaram a presença de sobreposição de nicho. Os resultados do UNTB revelaram baixo número de espécies. Os resultados da UPGMA demonstraram que a composição de espécies é específica para cada local, existindo diferenças marcadas. Os resultados expostos concordam com os resultados observados para os rios chileno central e norte da Patagônia, onde a composição das espécies é variável de acordo com as propriedades da bacia circundante e às condições sazonais.

Agricultural land covers approximately 40% of Earth’s land surface and affects hydromorphological, biogeochemical and ecological characteristics of fluvial networks. In the northern temperate region, agriculture also strongly affects the amount and molecular composition of dissolved organic matter (DOM), which constitutes the main vector of carbon transport from soils to fluvial networks and to the sea and is involved in a large variety of biogeochemical processes. Here, we provide first evidence about the wider occurrence of agricultural impacts on the concentration and composition of fluvial DOM across climate zones of the northern and southern hemispheres. Both extensive and intensive farming altered fluvial DOM towards a more microbial and less plant-derived composition. Moreover, intensive farming significantly increased dissolved organic nitrogen (DON) concentrations. The DOM composition change and DON concentration increase differed among climate zones and could be related to the intensity of current and historical nitrogen fertilizer use. As a result of agriculture intensification, increased DON concentrations and a more microbial-like DOM composition likely will enhance the reactivity of catchment DOM emissions, thereby fuelling the biogeochemical processing in fluvial networks and resulting in higher ecosystem productivity and CO2 outgassing.