Universidad de Magallanes
Not a member yet
1947 research outputs found
Sort by
Family farming systems: An index-based approach to the drivers of agroecological principles in the southern Andes
No full textGlobal social-ecological crises call for the identification and promotion of resilient agrifood systems. Agroecology can help addressing these challenges by fostering high levels of diversity and climate resilience. The application of agroecological principles (i.e. social-ecological processes translated into practices with positive effects on the conservation, stability and resilience of agriculture), increases systems' response capacity and ability to adapt to crises. Agroecology has its roots in indigenous agriculture but social-ecological filters (i.e. human-nature factors that remove or reinforce agroecological practices) may be, at times, shifting away these systems from agro-ecological principles. The dynamism of territories has prompted the arrival of new actors to rural areas such as lifestyle migrants. In this study, we assess the extent to which agroecological principles are present in family farming in the southern Andes and identify factors that can act as "social-ecological filters" of management practices, affecting the level of agroecology in these systems. We applied questionnaires to 80 gardeners (40 campesinos and 40 migrants), asking about 35 management practices and their socio-demographic profiles. We developed an Index of Agroecological Principles (IAP) to estimate the presence/absence of management practices that contribute to seven agroecological principles (four biological and three sociocultural). Most principles showed a presence over 0.5 (50%). We found a positive relationship between biological and cultural principles (r = 0.56; p < 0.01). Biodiversity was the principle with the highest presence (0.72&PLUSMN; 0.01). The value of the IAP was higher for indigenous and non-indigenous campesinos (4.5&PLUSMN; 0.1; ss = 4.27) than for migrants (3.9&PLUSMN; 0.12; ss =-0.4). The origin of the gardener, the age of the homegarden and the size of the farm, were the most influential social-ecological filters that selectively remove or reinforce agroecological practices in homegardens. We discuss the potential of an Index of Agroecological Principles in homegarden management for strengthening agroecology and resilience to social-ecological changes in a Global Biodiversity Hotspot and beyond
Laevilacunaria (Mollusca, Gastropoda) in the Southern Ocean: A comprehensive occurrence dataset
No full textBackground The present dataset is a compilation of georeferenced occurrences of the littorinid genus Laevilacunaria Powell, 1951 (Mollusca, Gastropoda) in the Southern Ocean. Occurrence data were obtained from field expeditions (Antarctic and sub-Antarctic sampling) between 2015 and 2022, together with a review of published literature including records from 1887 to 2022. Three Laevilacunaria species have been recorded from the Southern Ocean: Laevilacunaria bennetti, L. antarctica and L. pumilio.New information The present dataset includes 75 occurrences, representing the most exhaustive database of this Antarctic and sub-Antarctic littorinid genus. The publication of this data paper was funded by the Belgian Science Policy Office (BELSPO, contract n degrees FR/36/AN1/AntaBIS) in the Framework of EU-Lifewatch as a contribution to the SCAR Antarctic biodiversity portal (biodiversity.aq)
Integrating the Sustainable Development Goals into the strategy of higher education institutions
No full textDespite the relevance of the UN Sustainable Development Goals (SDGs) and the fact that universities may make valuable contributions towards their implementation, there is a paucity of international studies which may allow an assessment of their degree of engagement or their performance against the SDGs. This paper reports on an international study among a sample of 128 members of higher education institutions (HEIs) located in 28 countries, which aimed at ascertaining the extent to which the SDGs are being integrated into the strategy of HEIs. The focus of this paper is on the means which have been deployed by various universities in order to embed or include the SDGs in their activities. More specifically, this paper explores 1) the scope of integration, 2) the organisational influences, and 3) strategic influencing factors. The research identified the fact that, whereas many organisations are aware of the need for and the relevance of sustainable development and consider it as part of their institutional settings, the same cannot be said for the SDGs, whose level of emphasis is that many HEIs are comparatively somewhat limited. In addition, there seems to be a shortage of training opportunities focusing on the SDGs, which could equip university staff to handle this topic. Against this background, the paper describes some measures that may be implemented to make the SDGs more present in HEI programmes, hence maximising their contribution to addressing the global sustainability challenges
Quantifying the porosity of natural reservoirs with nuclear magnetic resonance
No full textDaniela Navarro-Perez explains how nuclear magnetic resonance can be used to assess the capacity of natural reservoirs to store fluids
"Pay Attention, Dive with Eyes Wide Open": A Field Environmental Philosophy Activity to Foster Reciprocity Between People and Nature
No full textThis chapter presents a case study of a diving experience co-designed with the participation of Yaghan fishers, scientists, and philosophers. It is an adaptation of the field environmental philosophy (FEP) methodology, which is based on the conceptual framework of the biocultural ethic. By experiencing interrelationships with macroalgae and various invertebrates, the activity integrates the ecological knowledge of the different participants to forge a “biocultural lens” that guides the participants to understand the concept of co-inhabitant which is basic to biocultural ethics. Through “face-to-face” encounters with the otherness of algae, mollusks, and other submerged invertebrates in the kelp forests of Cape Horn, this FEP activity helps participants to experience ancestral and novel ways of seeing, feeling, and co-inhabiting with marine biodiversity
Maternal history of maltreatment and offspring's emotional and behavioral problems in adolescence: Do family factors contribute to the intergenerational risk transmission?
No full textBackground: A history of childhood maltreatment often has a negative and long-lasting impact across different domains in life. A childhood maltreatment experience in parents may even affect the next generation. So far, the effects of family factors have been considered in the intergenerational transmission of adversity across the childhood years, but whether the effects remain until adolescence is less clear. Objective: Using data from a large population-based study in the Netherlands, including both mother and child reports, we examined whether maternal childhood maltreatment history is associated with increased mental health problems in offspring and the role of family functioning and harsh parenting as a potential pathway. Participants: 4912 adolescents (aged 13 years) and their mothers were recruited in the Generation R study. Methods: Mothers reported childhood maltreatment experiences using the Childhood Trauma Questionnaire (CTQ), and adolescents reported on their mental health using the Youth Self Report (YSR). Structural equation modeling (SEM) was used to test the association of maternal childhood maltreatment on mental health problems in offspring and family functioning and harsh parenting as mechanisms to explain this association. Results: Adolescents of mothers with a history of maltreatment had greater internalizing (beta = 0.07, p < .01) and externalizing problems (beta = 0.08, p < .01). Moreover, we found an indirect effect via family functioning over time and harsh parenting at ages 3 and 8 years which mediated this association. Conclusion: We concluded an intergenerational effect of maternal childhood maltreatment on adolescents internalizing and externalizing problems. The findings might enable earlier intervention within the family context to mitigate the consequences of maternal childhood maltreatment
Contrasting environmental conditions precluded lower availability of Antarctic krill affecting breeding chinstrap penguins in the Antarctic Peninsula
No full textDramatic decreases of chinstrap penguin populations across the Antarctic Peninsula (AP) are thought to be influenced by climate-driven changes affecting its main prey, the Antarctic krill, however, empirical evidence supporting such hypotheses are scarce. By coupling data on breeding chinstrap penguins, environmental remote sensing and estimates of krill acoustic density, we were able to demonstrate that penguins substantially increased their foraging effort in a year of low krill availability, with consequent reduction in breeding success. A winter of low sea ice cover followed by a summer/spring with stronger wind and lower marine productivity explained the lower and deeper krill availability. Our results highlight the importance of environmental variability on penguin populations, as variability is expected to increase under climate change, affecting foraging behaviour responses
Biomechanical gait effects of a single intervention with wearable closed loop control FES system in chronic stroke patients. A proof-of-concept pilot study
No full textFoot drop is a gait disturbance characterized by difficulty in performing ankle dorsiflexion during the swing phase of the gait cycle. Current available evidence shows that functional electrical stimulation (FES) on the musculature responsible for dorsal ankle flexion during gait can have positive effects on walking ability. This study aims to present a proof of concept for a novel easy-to-use FES system and evaluates the biomechanical effects during gait in stroke patients, compared to unassisted walking. Gait was quantitatively evaluated in a movement analysis laboratory for five subjects with chronic stroke, in basal condition without assistance and in gait assisted with FES. Improvements were found in all temporospatial parameters during FES-assisted gait, evidenced by statistically significant differences only in gait speed (p=0.02). Joint kinematics showed positive changes in hip abduction and ankle dorsiflexion variables during the swing phase of the gait cycle. No significant differences were found in the Gait Deviation Index. In conclusion, the present pilot study demonstrates that the use of this FES system in the tibialis anterior muscle can cause gait functional improvements in subjects with foot drop due to chronic stroke
Technical note: Skirt chamber - an open dynamic method for the rapid and minimally intrusive measurement of greenhouse gas emissions from peatlands
No full textWe present a reliable and robust open dynamic chamber for measuring greenhouse gas exchange in peatlands with minimal disturbance of the ground. This chamber, called the "skirt chamber", is based on a transparent plastic film placed above an open frame made of sparse interwoven wires and expanded around the base of the chamber below a steel chain that ensures contact to the ground, avoiding damage, trenching, and cutting vegetation. Gas exchange is determined using a portable gas analyzer from a mass balance in which the imperfect sealing of the chamber to the ground is quantified through the injection of a methane pulse. The method was tested on a pristine peatland dominated by Sphagnum magellanicum located on Navarino Island in the subantarctic Magellanic ecoregion in Chile. Our results indicate that the skirt chamber allowed the determination of methane fluxes and ecosystem respiration in about 20 min, with a limit of detection of 0.185 mg CH4 m(-2) h(-1) and 173 mg CO2 m(-2) h(-1), respectively. We conclude that the skirt chamber is a minimally intrusive, fast, portable, and inexpensive method that allows the quantification of greenhouse gas emissions with high spatial resolution in remote locations and without delay
Biogeography of microbial communities in high-latitude ecosystems: Contrasting drivers for methanogens, methanotrophs and global prokaryotes
No full textMethane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands, forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated with 16S rDNA amplicon sequences to determine the structure of the overall microbial communities and of specific methanogenic and methanotrophic guilds. Physicochemistry (especially pH) explained the largest proportion of variation in guild composition, confirming species sorting (i.e., environmental filtering) as a key mechanism in microbial assembly. Geographic distance impacted more strongly beta diversity for (i) methanogens and methanotrophs than the overall prokaryotes and, (ii) the sediment habitat, suggesting that dispersal limitation contributed to shape the communities of methane-cycling microorganisms. Bioindicator taxa characterising different ecological niches (i.e., specific combinations of geographic, climatic and physicochemical variables) were identified, highlighting the importance of Methanoregula as generalist methanogens. Methylocystis and Methylocapsa were key methanotrophs in low pH niches while Methylobacter and Methylomonadaceae in neutral environments. This work gives insight into the present and projected distribution of methane-cycling microbes at high latitudes under climate change predictions, which is crucial for constraining their impact on greenhouse gas budgets