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Las medidas decretadas para controlar la pandemia causado por el COVID-19 están impactando y desafiando la producción agrícola y los sistemas alimentarios. Sin embargo, la crisis puede incentivar el desarrollo de sistemas alimentarios locales, basado en la agroecología y sostenido por redes alimentarias cívicas. En un estudio de caso en la Comarca Andina, Argentina, a través de una encuesta a productores/as, i) sintetizamos los impactos de la primer fase de crisis (Marzo-Junio del 2020) sobre los productores/as de la zona de estudio, y ii) documentamos las estrategias inmediatas de adaptación y propuestas para responder a los impactos. Los/las encuestados/as percibieron fuertes impactos, y realizaron estrategias diversas de adaptación en el armado de redes de comercialización local. A mediano plazo adaptaciones están dirigidas a expansión y diversificación de la producción y comercialización local. Por un lado, los resultados indican que los impactos vislumbran debilidades de los sistemas establecidos, por ejemplo, la alta demanda de movilidad para trasladar insumos, productos y servicios. Por otro lado, los/las productores/as muestran capacidades adaptivas inmediatas en la implementación de estrategias de descentralización y diversificación, potencialmente fomentando procesos locales de transición agroecológica. Partiendo de este estudio de base concluimos con líneas futuras de investigación al respecto.

M. Pajola et al., On 2022 September 26, the DART spacecraft will impact the surface of Dimorphos, the ∼160 m size satellite of the binary near-Earth asteroid (NEA) (65803) Didymos. What will be observed on the surfaces of both asteroids and at the DART impact site is largely unknown, beyond the details of Didymos revealed by previous Arecibo and Goldstone radar observations. We present here the expected DART and LICIACube observations of the Didymos system and discuss the planned mapping strategies. By searching similar geological features and processes identified on other NEAs, we constrain the impact conditions that DART might encounter at Dimorphos, assessing both the asteroid's surface and interior structure., This work was supported by the Italian Space Agency (ASI) within the LICIACube project (ASI-INAF agreement AC n. 2019-31-HH.0). This work was supported by the DART mission, NASA Contract No. 80MSFC20D0004. E.A. is funded by the University of Arizona. S.S. acknowledges support from NASA as part of the Double Asteroid Redirection Test (DART) Participating Scientist Program. J.M.T.-R. is funded by the research project (PGC2018-097374-B-I00), funded by FEDER/Ministerio de Ciencia e Innovación—Agencia Estatal de Investigación. P.M. acknowledges ESA as well as funding from the French space agency CNES, from the European Union's Horizon 2020 research and innovation program under grant agreement No. 870377 (project NEO-MAPP) and from the CNRS through the MITI interdisciplinary programs.

Fil: Szudruk Pascual, María Noel. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Szudruk Pascual, María Noel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Chillo, Verónica. Instituto de Investigaciones Forestales y Agropecuarias de Bariloche. Río Negro, Argentina. Fil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Amoroso, Mariano Martín. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Amoroso, Mariano Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Arthropods are key nodes for the provision of ecosystem services such as pest control, but their response to land-use change is highly variable depending on the scale of analysis and the natural enemies’ life histories. We evaluate the effects of landscape- and local-scale variables of natural enemies’ communities on small-scale agriculture. We consider functional response traits to attain a mechanistic understanding of the effect of land-use changes on the biodiversity and resilience of natural enemies’ communities. Predator and parasitoid arthropods were collected from thirteen raspberry farms to estimate functional diversity, complementarity, and redundancy indices. We found no effects of landscape heterogeneity, local habitat, or management practices on natural enemies’ functional diversity. Regarding resilience, complementarity was high at most of the sites and was not affected by the landscape or local variables. However, redundancy was affected by two management practices. Weed control decreased natural enemies’ abundance as well as the abundance of walker generalist predators and flying specialist parasitoids, while habitat richness decreased flying generalist predators. These results highlight the importance of management when the landscape matrix is heterogeneous. We conclude that small-scale agriculture in a heterogeneous landscape supports a functionally diverse enemy community, potentially promoting the resilience of pest control to land-use change.

Fil: Goldenberg, Matías G. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Goldenberg, Matías G. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Oddi, Facundo J. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Oddi, Facundo J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Amoroso, Mariano M. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Amoroso, Mariano M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Forest biomass with energy purpose is gaining importance. Although there is a lot of information about afforestation for energy purpose, native resource management for biofuel production is a less studied topic. Consequently, generating information about management of local forest types that have potential for providing biomass for energy, such as resprouting shrublands, becomes a priority objective. We evaluated the effects of harvesting intensity on coppice growth in three resprouting shrublands with contrasting site conditions in northern Patagonia (Argentina). At each site, three harvesting treatments in strips of increasing width were randomly assigned to six permanent plots of 31.5 × 45 m during 2013–2014. Four years after, we measured resprouts (number and size of stems) of the five native dominant species. We found that almost all species responded to harvesting intensity by enhancing the coppice growth rates. Nonetheless, species showed different strategies for resource obtention. When analyzing at the community level, the response to harvesting intensity was consistent among the hillside sites, but conservative in the valley bottom site with the worst environmental conditions. Due to the high response of these species to harvesting intensity, we conclude that intense shrubland management for biomass commercialization could be a viable option depending on site conditions.

There is a significant dendrochronological gap in the Puna of the central Andes of Peru, which motivates research on new species. In this study, we present the first tree-ring chronologies of Escallonia myrtilloides. We collected samples at San Pedro Sano and Sapallanga in Peru, analyzed the anatomical characteristics that delimit the annual growth rings, and developed two tree-ring chronologies through conventional dendrochronological techniques. The tree-ring chronologies cover the period 1940–2015 (76 years) for San Pedro Sano and 1960–2015 (56 years) for Sapallanga. The E. myrtilloides chronologies presented similar values of mean sensitivity, Rbar and EPS to those recorded for Polylepis tarapacana, Polylepis pepei, and Polylepis rugulosa in the Puna region. The analysis of the climate-growth relationships indicated positive correlations with precipitation and negative correlations with temperature in particular months of the current growing season (October–April). This precipitation/temperature-sensitive record highlights the high value of E. myrtilloides for future studies on the influence of climate on tree growth in the central Andes.

Cold air incursions over subtropical South America are the precursor conditions for frost, a recognized extreme thermal weather event affecting plant growth damaging agricultural production over the whole Argentinian territory. Given that sub-freezing temperatures occurring during the active growing season may harm the cambium tissues and their daughter cells, frost injury can be recorded in annual tree rings in the form of anatomical anomalies. For this study, six forest sites of Araucaria araucana, a multi-centennial tree species, from NW Patagonia were considered. From 321 trees, 1374 frost injuries in the growth rings, named frost rings, were identified and their calendar dating allowed the development of a regional chronology of frost rings covering the period AD 1256 to AD 1993 (738 yrs.). This represents the longest record at present of extreme low thermal events for Patagonia. Frost injuries were mostly restricted to the middle section of the growth rings, suggesting the incidence of late spring frosts. Moreover, frost rings were observed mainly in the juvenile portions (

The smallest member of the Didymos binary near-Earth object system (Dimorphos) is the target of the DART/LICIACube mission, the first attempt to change the orbit of another celestial body via a kinetic impactor. It is important to characterize the unperturbed system prior to the DART impact. In this work we obtained, for the first time, spectral characterization of the system at several rotational phases from TNG+DOLORES in the visible range (0.34–0.81 μm). This is crucial in order to disentangle the primary and secondary bodies and highlight eventual dishomogeneities on their surfaces. We confirm that a subtle but persistent spectral variability appears, even when compared with data obtained from previous 2003 and 2019 apparitions. While the reason for such variability is still under investigation, our analysis hints that different compositions could play a role. Future observations during the brighter 2022 apparition in synergy with data obtained from LUKE on board LICIACube will definitely tackle this conundrum.

Challenged by COVID-19, we sought ways to increase engagement in the virtual classroom, capitalizing on a popular multiplayer game to teach persuasion to undergraduate students. In the game Among Us ®, players (“Crewmates”) work together to repair their spaceship before it explodes while being attacked by other players (“Impostors”). The structure of the game lends itself to the use of persuasion and influence tactics and provides the basis for a fun, applied learning activity, designed to take 1 hour. We provide detailed instructions for preparing students for the game, running the game, and debriefing. While the constraints resulting from COVID-19 inspired the adoption of this activity for the classroom, we believe it can work well in both virtual and face-to-face classrooms.

Silvopastoral systems (SPS) are sustainable production systems, characterized by a great biodiversity and multifunctionality compared with other livestock production systems. Northern Argentine-Chilean Andean Patagonia is a complex socio-ecological system where the provision and perception of ecosystem services (ES) vary depending on multiple contexts. We aim to characterize multiple ES and the associated benefits from SPS under different contexts and key factors. We propose a conceptual model of the socio-ecosystem that considers socio-historical contexts, forest ecosystems, cultural contexts, relational values, and anthropogenic aspects. We provide a deep review of published information on these factors and how these are related to the provision and perception of ES. We also consider natural and anthropogenic drivers to assist government and institutions. Finally, we discuss the main knowledge gaps that need to be addressed to attain a sustainable management. There is a need for a multidisciplinary and regional approach that can serve as a new interpretive framework for managers and decision-makers. In particular, the inclusion of relational values with nature and the visibility of anthropocentric factors can be useful tools for local development.

Severe droughts have the potential to reduce forest productivity and trigger tree mortality. Most trees face several drought events during their life and therefore resilience to dry conditions may be crucial to long-term survival. We assessed how growth resilience to severe droughts, including its components resistance and recovery, is related to the ability to survive future droughts by using a tree-ring database of surviving and now-dead trees from 118 sites (22 species, >3,500 trees). We found that, across the variety of regions and species sampled, trees that died during water shortages were less resilient to previous non-lethal droughts, relative to coexisting surviving trees of the same species. In angiosperms, drought-related mortality risk is associated with lower resistance (low capacity to reduce impact of the initial drought), while it is related to reduced recovery (low capacity to attain pre-drought growth rates) in gymnosperms. The different resilience strategies in these two taxonomic groups open new avenues to improve our understanding and prediction of drought-induced mortality., Resilience to drought is crucial for tree survival under climate change. Here, DeSoto et al. show that trees that died during drought were less resilient to previous dry events compared to surviving conspecifics, but the resilience strategies differ between angiosperms and gymnosperms.

The identification of disturbance events using disturbance chronologies has become a valuable tool in reconstructing disturbance history in temperate forests worldwide, yet detailed reconstructions of disturbance history and their effect on the structure and dynamics of the old-growth Nothofagus forests in the southern Patagonia are scarce. We reconstructed forest dynamics and disturbance history of an old-growth N. pumilio forest in the Toro River Valley, Santa Cruz, Argentina using dendroecological techniques. Since a variation in the disturbance regimes was expected with changing elevation, we sampled at different elevations. We found distinct differences in forest structure, dynamics, and disturbance history with changes in the elevation. The disturbance chronologies provided robust evidence that forests in the study area have been subjected to multiple disturbance events over the last 200 years. Yet, recognizing the agent of disturbance could be difficult in these montane forests and further studies are required. Moreover, disturbances might have varied from frequent, moderate- to high-severity events to less frequent and more severe events. This study represents the first of its kind for the temperate forests of Patagonia.

The interest in near earth objects (NEOs) has widely spread among space agencies during the past decades, not only due to the valuable scientific data these objects can provide, but also for the potential hazard they represent for our planet. In particular, to date there still isn't a validated technique to deflect NEOs on a collision course with Earth. The DART mission, developed by NASA, aims at filling this gap, by testing the effectiveness of a kinetic impactor on the binary asteroid system "Didymos". In 2022 the spacecraft will hit the smaller asteroid of the binary system, slowing down the moonlet speed with respect to the larger body, permitting the assessment of the impact effectiveness by ground observation measurements. The impact will also generate a cone of ejected particles, of great interest for current numerical impact models validation, which however will be hardly visible from ground. In this context, a bilateral agreement between NASA and Italian Space Agency (ASI) allowed to embark a 6-units CubeSat on DART, called Light Italian Cubesat for Imaging of Asteroids (LICIA). Deployed before the impact, it will fly by the asteroid at the right distance to observe the ejecta evolution and will also be exploited for observation of the asteroid's side not visible from DART, to help estimating the overall volume. The LICIA spacecraft and mission are being developed by ASI through an italian consortium composed by Istituto Nazionale di Astrofisica (INAF), Università di Bologna (UniBo), Argotec, and Politecnico di Milano (PoliMi), respectively covering the fields of mission science and payload, orbit determination, platform development, and mission analysis. The present paper covers the topic of attitude guidance and control design, to ensure the best performance for target pointing during the flyby. The most up-to-date trajectory is taken as baseline scenario to explore various strategies in terms of slew maneuvers to be performed, and optimization for the parameters of the controller. Uncertainties, for the platform and the environment, are introduced to evaluate such strategies in non-nominal, realistic scenarios, with deviations of the trajectory and changes in the flyby distance from the target. Results are compared and the best guidance and control strategy is selected as preliminary baseline. Next steps in the closed-loop architecture development, and related expected issues to be solved, are discussed.

On September 30, 2022, NASA's Double Asteroid Redirection Test (DART) mission will be the first space mission demonstrating the kinetic impactor method for planetary defense. DART will impact Didy- mos B (a 164±18 m secondary of asteroid (65803) Did- ymos) with its mass of 650 kg and at a speed of 6.6 km/s. Such impact is expected to change the secondary orbital period by about 10 minutes. DART will carry as a piggyback the Light Italian Cubesat for Imaging of Asteroids (LICIACube) which will be released from DART ten days before the impact. LICIACube will pro- vide evidence of the impact and will take multiple im- ages of the target up to a distance of ~55 km from the target. The LICIACube narrow and wide angle cameras - LEIA (LICIACube Explorer Imaging for Asteroid) and LUKE (LICIACube Unit Key Explorer), respec- tively - will capture the post-impact processes coming from in situ events, such as the newly formed crater, the expanding ejecta and the dynamics of its plume. In par- ticular, the measurement of the motion of the slow (

Whereas tree establishment after large-scale disturbances such as fires, avalanches, and landslides have been documented for Patagonian forests, information on forest recovery following floods is scarce. Glaciar Perito Moreno has remained stable throughout the twentieth century, reaching the Peninsula de Magallanes several times and embalming parts of Lago Argentino. Following each ice-dam flood, the Nothofagus forests along the flooded shores die. We combined dendrochronology and spatial statistics to describe forest recolonization following the episodic flood caused by this glacier in 1988. Four tree species recolonized the lakeshores after the flood. Tree establishment started during spring-summer 1988–1989, the growing season following the break of the ice dam in February 1988. More than 60% of the trees were established between the years 1994–2000, suggesting a rapid colonization of bare shores after the ice-dam break. Using Ripley’s spatial analysis, a 100% significant association between species was recorded at sites where two or more species were present. Species dominance was largely modulated by the composition of neighboring non-flooded forests and the climatic conditions along the precipitation gradient. While rates of tree colonization are influenced by species and their seed dispersal capacities, the grouping patterns by site may be modulated by differences in substrate and microclimatic conditions.

The study of forest dynamics over large temporal and spatial scales has widely benefited from dendrochronological techniques. Patagonia is home to several long-lived tree species (Austrocedrus chilensis, Araucaria araucana, Fitzroya cupressoides, Nothofagus dombeyi and N. pumilio) with well-defined tree rings suitable for reconstructing tree establishment, mortality, spatio-temporal growth patterns and disturbance regimes with annual resolution. The first dendrochronological studies in the region date back to the 1950s and had a strong emphasis on hydroclimatology. It was not until the last few decades that studies using dendroecological techniques began to emerge. In this chapter, we review the experience gained by the tree-ring lab at IANIGLA (CONICET, Mendoza, Argentina) and colleagues from other institutions over the past 30 years applying dendroecological techniques to understand the role of climate and disturbances (insect outbreaks, snow avalanches, windblows, fires and decline) on forest dynamics. For each case, we summarized the process, and the dendrocronological methods used. In this way, it was possible to detect those gaps of knowledge that still can be explored using dendroecological methods in the Patagonian forests of Argentina.

The authors describe the efforts of the faculty and administration at a small, Midwestern, Association to Advance Collegiate Schools of Business–accredited school to improve business students’ care...