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The construction of fuel moisture content (FMC) maps, as well as temperature, terrain topography, and wind speed maps, are essential for the development of fire susceptibility models in forested areas. Moisture distribution in tree canopies requires exploration and a three-dimensional representation. This paper presents the construction of FMC maps expressed as vegetation indices (VIs) in a point cloud. Multispectral images were captured by a camera mounted on an unmanned aerial vehicle to create the point cloud. VIs were estimated in the points that belonged to the forest canopy. To classify the canopy points, we a combination of filtering of ground points and thresholding of VIs was evaluated. On such canopy points, random forest (RF), kernel ridge regression (KRR), and Gaussian process retrieval (GPR) regressors were investigated to estimate twelve VIs related to FMC. The input set of the models consisted of the points representing five wavelengths provided by the multispectral camera. The ground truth of VIs was obtained using a spectrometer. The study area was a 1 ha forest of Pinus radiata in the Maule Region, Chile. The results demonstrated that combining ground filtering and VIs thresholding for canopy points segmentation achieved a precision of 93.27%, recall of 95.65%, F1 score of 90.12%, and accuracy of 87.82%. Furthermore, the recovery of the VIs using GPR achieved a root mean square error of 0.175 and a coefficient of determination of 0.18. According to the correlation coefficient, GPR was able to recover eleven of the twelve VIs, KRR recovered three, and RF failed to recover any. [Display omitted] • A sensitivity analysis was performed to find a vegetation index threshold. • Vegetation indices and geometric soil filtering improves point cloud segmentation. • Gaussian process retrieval estimated eleven of the twelve vegetation indices. • A vegetation index map was constructed from photogrammetry and machine learning. [ABSTRACT FROM AUTHOR]

Ganymede's surface exhibits great geological diversity, with old dark terrains, expressed through the surface composition, which is known to be dominated by two constituents: H 2 O-ice and an unidentified darkening agent. In this paper, new investigations of the composition of Ganymede's surface at global scale are presented. The analyses are derived from the linear spectral modeling of a high spectral resolution dataset, acquired with the near-infrared (1.40–2.50 μm) ground-based integral field spectrometer SINFONI (SIN gle F aint O bject N ear-IR I nvestigation) of the Very Large Telescope (VLT hereafter) located in Chile. We show that, unlike the neighboring moon Europa, photometric corrections cannot be performed using a simple Lambertian model. However, we find that the Oren-Nayar (1994) model, generalizing the Lambert's law for rough surfaces, produces excellent results. Spectral modeling confirms that Ganymede's surface composition is dominated by H 2 O-ice, which is predominantly crystalline, as well as a darkening agent, but it also clearly highlights the necessity of secondary species to better fit the measurements: sulfuric acid hydrate and salts, likely sulfates and chlorinated. A latitudinal gradient and a hemispherical dichotomy are the strongest spatial patterns observed for the darkening agent, the H 2 O-ice, and the sulfuric acid: the darkening agent is by far the major compound at the equator and mid-latitudes (≤ ± 35°N), especially on the trailing hemisphere, while the H 2 O-ice and the sulfuric acid are mostly located at high latitudes and on the leading hemisphere. This anti-correlation is likely a consequence of the bombardment of the constituents in the Jovian magnetosphere which are much more intense at latitudes higher than ±35°N. Furthermore, the modeling confirms that polar caps are enriched in small, fresh, H 2 O-ice grains (i.e. ≤50 μm) while equatorial regions are mostly composed of larger grains (i.e. ≥200 μm, up to 1 mm). Finally, the spatial distribution of the salts is neither related to the Jovian magnetospheric bombardment nor the craters. These species are mostly detected on bright grooved terrains surrounding darker areas. Endogenous processes, such as freezing of upwelling fluids going through the ice shell, may explain this distribution. In addition, a small spectral residue that might be related to brines and/or hydrated silica-bearing minerals are located in the same areas. • Near-infrared global mapping of Ganymede's surface from a ground-based telescope • Overall, an unidentified darkening agent is the major compound around the equator. • The water ice, mostly the crystalline form, is dominant at high latitudes (≥ ± 40°N). • Salts, very likely endogenic, improve spectral modeling for young geological regions. • A hemispherical dichotomy, due to Jupiter's magnetospheric bombardment, is observed. [ABSTRACT FROM AUTHOR]

This paper examines the effectiveness of intrinsic and extrinsic motivations on the adoption intensity of sustainable agricultural practices (SAPs) among annual crop farmers in Chile. We use the farmers' attitude towards SAPs as a proxy of intrinsic motivation, while extrinsic motivation is represented by an economic incentive to promote the use of SAPs. The policy program we studied is administered by the Chilean Ministry of Agriculture under the name System of Incentives for the Agro-Environmental Sustainability of Degraded Soils (SIRSD-S. Sustainable behaviour was defined as the adoption of (1) minimum tillage, (2) improved fallow, (3) stubble incorporation, (4) use of manure, and (5) use of compost. A count model was estimated that showed that both sources of motivation, and the interaction between them, significantly predicted the adoption of SAPs. Farmers with low levels of intrinsic motivation depended largely on the SIRSD-S to adopt SAPs, while the incentive was ineffective for intrinsically motivated farmers who adopted more SAPs regardless the presence of extrinsic motivation. Finally, the perception of risk of soil erosion and perceived behavioural control of this risk were found to play a positive role in the adoption of SAPs. • A motivational model of sustainable behavior is estimated at the farm level. • Sustainable behaviour is driven by intrinsic and extrinsic motivations. • Motivations interact negatively, lessening one's effects as the other increases. • A monetary incentive does not affect behaviour when intrinsic motivation is high. • Risk perception and perceived behavioural control foster sustainable agriculture. [ABSTRACT FROM AUTHOR]

This paper reviews the unique situation of perchlorate contamination in Chile, including its sources, presence in environmental media and in the human population, and possible steps to mitigate its health impacts. Perchlorate is a ubiquitous water contaminant that inhibits thyroid function. Standards for drinking water range from 2 to 18 µg L −1 in United States and Europe. A major natural source of perchlorate contamination is Chile saltpeter, found in the Atacama Desert. High concentrations of perchlorate have presumably existed in this region, in soils, sediments, surface waters and groundwaters, for millions of years. As a result of this presence, and the use of Chile saltpeter as a nitrogen fertilizer, perchlorate in Chile has been found at concentrations as high as 1480 µg L −1 in drinking water, 140 µg/kg −1 in fruits, and 30 µg L −1 in wine. Health studies in Chile have shown concentrations of 100 µg L − 1 in breast milk and 20 µg L −1 in neonatal serum. It is important to acknowledge perchlorate as a potential health concern in Chile, and assess mitigation strategies. A more thorough survey of perchlorate in Chilean soils, sediments, surface waters, groundwaters, and food products can help better assess the risks and potentially develop standards. Also, perchlorate treatment technologies should be more closely assessed for relevance to Chile. The Atacama Desert is a unique biogeochemical environment, with millions of years of perchlorate exposure, which can be mined for novel perchlorate-reducing microorganisms, potentially leading to new biological treatment processes for perchlorate-containing waters, brines, and fertilizers. [ABSTRACT FROM AUTHOR]

Environmental education is regarded as a key instrument for promoting pro-environmental behavior in early childhood. In this paper, we analyze the transmission process within a personal value system including knowledge, attitudes, and practices (KAP) regarding the consumption and disposal of plastics among school children, and the extent to which parents play a role in mediating that transmission. The study gathers data from a sample of 1,521 children in southern Chile. Results evidence that the transmission of value systems is a recursive and hierarchical process, where knowledge mediates attitudes, and attitudes (and knowledge) mediate practices. We also find evidence that parents' behavior significantly explains children's behavior in all domains of KAP, with stronger connections among practices where children and parents interact more closely (e.g., packing a lunch box) and in those that are more visible to children (e.g. recycling). • Plastics in the marine environment are of increasing global concern. • Environmental education is key to promote pro-environmental behavior in early childhood. • We analyze transmission of knowledge, attitudes and practices regarding plastics among children. • We find that transmission follows a hierarchical structure, where parents play a key role. [ABSTRACT FROM AUTHOR]

Abstract: The consumption of plant-derived hallucinogenic substances through smoking and snuffing is a long-standing tradition in the south-central Andes. Chemical and archaeobotanical evidence point to the consumption of nicotine and tryptamine alkaloids in Northwestern Argentina and of tryptamine alkaloids in San Pedro de Atacama (SPA), in prehispanic times. In this paper, results are reported of gas chromatography–mass spectrometry (GC/MS) analyses aimed at identifying nicotine and tryptamine alkaloids in the hair of mummies from different cultural periods of SPA. Fifty-six samples were examined. While tryptamines were not found in any of the samples, nicotine was found in 35 samples, assigned to the Late Formative (1 of 1 sample from this period), Late Formative or Middle (1 of 2 samples from either of these periods), Middle (4 of 6 samples from this period) and Late Intermediate periods (8 of 12 samples from this period), or without assignment to period due to lack of contextual information (21 of 35 samples unassigned to a period). These results show a continuous consumption of nicotine from the Late Formative to the Late Intermediate periods of SPA (ca. 100 B.C.–1450 A.D.). No associations were found between presence of nicotine in the hair of mummies and presence of snuffing trays or of other snuffing paraphernalia in the corresponding tomb; furthermore, neither the diversity of the funerary context, measured in terms of the number of types of objects, nor the presence of gemstone necklaces differed between tombs with mummies with or without nicotine in their hair. Overall, these results suggest that consumption of nicotine was performed by members of the society at large, irrespective of their social and wealth status. [Copyright &y& Elsevier]

Abstract: On the basis of stable carbon and nitrogen isotope analysis of human remains, this paper provides evidence for the retention of hunter–gatherer economies among coastal inhabitants in northern Chile during the late Holocene – at the same time that inland populations were adopting agricultural economies. Coastal diets from the Caleta Vitor region of the Atacama Desert were dominated by marine-based foods, predominantly from upper trophic levels. The focus on reliable marine food resources is interpreted as a risk minimisation strategy in this marginal arid environment. Although these coastal hunter–gatherers adopted other goods and traditions from agricultural populations, their participation in this larger interregional exchange network did not affect their basic subsistence economies. Associated new radiocarbon dates from the site are also discussed. Skeletal remains and artefacts associated with the Caleta Vitor shell middens generally originate from sites with dates ranging from c. 9000–476 BP. However, the human remains that are the subject of this research cover the time period c. 4000–476 BP. [Copyright &y& Elsevier]

Simazine is a soil-active herbicide that has been applied worldwide in agricultural soils, being the second most commonly detected herbicide in groundwater and surface waters. Although its use has been restricted in many countries of Europe, it is still applied in many locations around the world in orchards, vineyards and forestry. Therefore, it is important to study its fate and transport in the environment. This paper investigates simazine transport in undisturbed bare soils from a vineyard at the Casablanca valley, Chile. In the study site, shallow groundwater tables (<1.0 m depth) and high simazine levels (>15 μg L−1) in the groundwater were observed and thus, there is potential for simazine to be transported further away through the saturated zone. The soils from the study site were characterized and the hydrodynamic transport parameters were determined. Column leaching experiments showed that the two-site chemical non-equilibrium model correctly represented simazine transport. It was found that 36.3% of the adsorption sites achieve instantaneous equilibrium and that the first-order kinetic rate of the non-equilibrium sites was 6.2 × 10−3 h−1. Hydrus 2D was used to predict the transport of simazine in the study site under natural field conditions. Simulation results showed that simazine concentrations at depths shallower than 2.1 m are above the maximum contaminant level of 4 μg L−1 (defined by the U.S. Environmental Protection Agency). The timing of herbicide application was found to be important on simazine leaching and the main processes involved in simazine transport were degradation and adsorption, which accounted for 95.78 and 4.19% of the simulated mass of pesticide, respectively. A qualitative agreement in the timing and magnitude of simazine concentration was obtained between the simulations and the field data. Therefore, the model utilized in this investigation can be used to predict simazine transport and is a valuable tool to assess agricultural practices to minimize environmental impacts of simazine. [Copyright &y& Elsevier]

Abstract: Grazing by domestic exotic herbivores on native vegetation in Patagonian steppes has led to the deterioration of forage resources, where grasses are replaced by shrubs, and preferred grasses by non-preferred ones. Therefore, attempts at breeding and regeneration should start by identifying species with potential forage capability. Two perennial high-preferred species are the focus of this paper: Hordeum comosum and Koeleria vurilochensis. For the first time, we studied their morphological traits, dormancy level, and their temperature and water germination requirements, through thermal- and hydrotime models. H. comosum seeds were solid, large and heavy, while K. vurilochensis seeds were soft, small and light. Neither light-quality nor alternating temperature affected the dormancy level in seeds of both species. Seeds of H. comosum and K. vurilochensis required, respectively, 768.74 °Ch and 2217.89 °Ch to germinate; alternatively, base temperature was higher for H. comosum than for K. vurilochensis. The hydrotime required by H. comosum was 26 MPah and 110 Mpah for K. vurilochensis but, base water potential was −0.99 MPa and −1.45 MPa, respectively. For all the conditions, H. comosum displayed a higher germination rate compared to K. vurilochensis seeds. Deeper knowledge on the morphological and germination traits of seeds is a key step toward breeding and restoration of forage potential species. [Copyright &y& Elsevier]

Abstract: This paper incorporates an experimental approach to the study of violence patterns in Northeastern Patagonia (Argentina) during the late Holocene. The underlying hypothesis considers a close association between socio-ecologic alterations during the Medieval Climatic Anomaly (MCA) (ca. 1150–600 years BP; , ) and a probable increase in conflict levels. In order to test this hypothesis, human skulls (n = 986) were analyzed for bone lesions, discriminating late bone lesions, such as those produced by metal tools. The experimental approach used swine (Sus scrofa domestica) skulls, as proxies for human skulls, and incorporated original sabers. From this discriminating analysis, it can be inferred that no significant increase in violence signs were recorded until the first stages of Hispanic-indigenous contact (first half of 17th century). These findings emphasize the need for a revision of the implications of the dynamics of human populations in Northeastern Patagonia during the late Holocene. [Copyright &y& Elsevier]

Abstract: This paper explores the differential rates of diachronic change developed by diverse features of portable art in southern Tierra del Fuego. It is argued that decorative designs and techniques, which simultaneously constitute each decorated artefact, had asynchronic rates of change throughout the archaeological sequence. Results indicate that: (I) decorated harpoon points (1) had a broader and more complex design repertoire which entailed a higher labour investment and showed a faster rate of change than beads, due to a greater individual input in their decoration, (2) were richly decorated in spite of their high risk of loss/fracture, yet their decoration was concentrated in the early period of the archaeological sequence and then decreased in time due: a) to such loss/fracture risk, which jeopardised the labour invested in their decoration, (b) to a relative decrease in pinniped hunting which might have reduced the socio-economic and symbolic value of harpoons; (II) decorated beads (1) had a simpler and more standardised design repetoire which entailed a lower labour investment and showed a slower rate of change than harpoons, due to a stricter process of teaching/learning or imitation during their production and a collective way of ornamentation during their display, (2) increased with time and have been decorated during the three periods of the archaeological sequence due to: (a) their lower risk of loss/fracture, which did not endanger the labour invested in their decoration, (b) their social function as a shared form of ornamentation; (III) decorative techniques had a slower rate of change than decorative designs throughout the archaeological sequence due to their differential instrinsic variability potentials. [Copyright &y& Elsevier]

The main objective of this paper is to present a critical analysis of the stakeholder participation process within the Environmental Impact Assessment System in Chile, after ca. 14 years of being enforced. This analysis is sustained by the description and analysis of the stakeholder participation possibilities in a representative rural area of North-Central Chile. The Environmental Basis Act 19300, enacted in 1994, considers the participation of the local community in the environmental impact assessment of new projects. However, this possibility is very limited and difficult to exert, often resulting in frustration for the participants. This is due to a number of reasons, such as the imbalance of resources and knowledge among the majority of participating communities and project proponents, the complexity and administrative and legal constraints to participation, and the dominant interest of the Central Government in approving investments, specifically in energy and natural resources related projects, which generate wealth and jobs. Also, the State’s rush to develop Internet-based communication and management systems has built a barrier for poor, traditional communities. This factor is clearly reflected in the case study considered. Results show that there is generally a significant lack of knowledge about institutions and participation tools. From this base, we intend to raise concern on these selected aspects that could be addressed to improve the effectiveness of the existing framework, both in Chile and in other developing countries, where immature environmental impact assessment and public management systems face similar pressures in relation to the sustainable use of their natural resources. Finally, some basic steps are proposed in order to make the community participation an effective tool for sustainable development. [Copyright &y& Elsevier]

Abstract: The management and conservation of animal species should be based upon a long-term analysis that considers its geographical distribution and feeding patterns. The study of carbon and nitrogen stable isotopes on skeletal remains provides a quantitative approach to the paleodietary reconstructions and constitutes a potent tool for comparing behavioral aspects of the fauna. In this paper we present the first set of isotopic values for modern and archaeological samples of Huemul (Hippocamelus bisulcus) from the forests of Central-western Patagonia, Chile. Contrary to initial expectations, our analysis indicates that there is no evidence of an important incidence of the canopy effect on the δ13Ccollagen values, which we suggest is due to an ecological selection that drives the huemul to focus its predation on open sectors within the forest. On the other hand, a wide range of δ15Ncollagen values for huemul was verified. This could reflect the N impoverishment of the forest soils and provide an interesting ecological indicator. The long-term information offered by the archaeological record provides the necessary context for decision-making conducive towards the preservation of Hippocamelus bisulcus in Patagonia. [Copyright &y& Elsevier]

Abstract: In grazed semiarid ecosystems, considerable spatial variability in soil infiltration exists as a result of vegetation and soil patchiness. Despite widespread recognition that important interactions and feedbacks occur between vegetation, runoff and erosion, currently there is only limited quantitative information on the control mechanisms that lead to differences in infiltration from different vegetation types. In this paper, we determine (i) the relationship between vegetation and soil surface characteristics and (ii) the soil infiltration rate by using rainfall simulations on runoff plots (0.60 × 1.67 m) in three plant communities of northeastern Patagonia: grass (GS), degraded grass with scattered shrubs (DGS), and degraded shrub steppes (DSS). Our results clearly indicate that vegetation and soil infiltration are closely coupled. Total infiltration was significantly higher in the GS (69.6 mm) compared with the DGS and DSS (42.9 and 28.5 mm, respectively). In the GS, soil infiltration rate declined more slowly than the others communities, reaching a terminal infiltration rate significantly greater (57.7 mm) than those of DGS and DSS (25.7 and 12.9 mm, respectively). The high rate of water losses via overland-flow may limit the possibilities for grass seedling emergence and establishment and favor the persistent dominance of shrubs. [Copyright &y& Elsevier]

Abstract: Changes in the exploitation of resources among prehistoric hunter-gatherer-fishers of the Beagle Channel (Southern South America) are examined in this paper. Archaeological investigations show the prevalence of maritime hunter-gatherer organization throughout the occupation of the region (ca. 6400BP – 19th century). Notwithstanding, variations in the exploitation of different kind of animal resources have been detected, and a concomitant reorientation in the landscape use is then inferred. Zooarchaeological evidence from five shellmiddens is analyzed here: evenness measures and relative abundance prey types are used to evaluate such adjustments. Results indicate the major utilization of coastal and terrestrial ecozones and the predominance in the exploitation of mammals (pinnipeds and guanacos) in ancient occupations. While, during the Late Holocene an expansion in ranges of maritime mobility for subsistence is detected, which was associated with an increase in the representation of birds and fish in the zooarchaeological record. [Copyright &y& Elsevier]

Abstract: In extra-Andean Patagonia, wet meadows contrast with the prevailing arid steppes, and present a gradient of water availability from the periphery to the center. The objectives of this paper are to describe the spatial and temporal variation of aerial net primary production (ANPP) of Patagonian meadows, and to obtain a model for the relationship between the normalized difference vegetation index (NDVI) and ANPP. We determined ANPP in four regionally scattered meadows during 3–5 years and in three positions of the gradient of water availability. In one meadow, we correlated ANPP with NDVI during 2 years. Annual ANPP was 2–3 times larger in the center than in the periphery, and also varied 2–3 fold among the four meadows. The interannual variation of ANPP was high and similar across meadows and zones. ANPP was closely correlated with NDVI through a linear model. Within the growing season, the central zone had a more extended period of high NDVI into the summer than the peripheral and the intermediate zones. We conclude that (1) the local variation of ANPP across the gradient of water availability is strong and must be taken into account for management, and (2) the highly variable ANPP may be monitored by remote sensing. [Copyright &y& Elsevier]

Abstract: This paper explores to what extent arsenic poisoning affected pre-Columbian northern Chile populations living between Arica and Iquique cities. We hypothesize, the pre-Columbian inhabitants of this region, will show arseniasis according to modern geographic endemic levels. Continuous exposure to high levels of arsenic causes serious health problems. Today, in the Camarones valley, where many Chinchorro people lived, arsenic levels are 100 times above the 10 μg/L recommended by the World Health Organization (WHO). Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) we determined arsenic levels in a single strand of hair of 45 Arica mummies coming from ten sites (Morro 1, Morro 1/5, Yungay 372, Camarones 8, 9, 15D, and 17 and Azapa 140, Sermenia and Patillos), ranging from Chinchorro (ca. 5000–2000 years B.C.) to the Late Intermediate Period (1000–1400 years A.D.). Each hair was cleaned using distilled ionized water and placed on double sided mounting tape and ablated using a 266 nm Nd-YAG UV laser. Hair samples were also investigated for potential diagenesis. Results indicate minimal diagenesis. Arsenic hair (AsH) concentrations in the mummies ranged from <0.8 to 262.2 μg/g. We noted AsH variability within burial sites as well as regional variation. The Morro mummies have the highest mean group value (58 ± 103.8 mg/g). Contrary to hypothetical expectations, some Arica Chinchorro mummies have high values, perhaps indicating inter site mobility related to exogamous marriage and mummification rites. Our study shows that ancient people of northern Chile were significantly affected by arsenic poisoning throughout generations. Finally, this study calls attention to naturally occurring eco-toxic contaminants and its impact on ancient Andean people. [Copyright &y& Elsevier]

Abstract: Annual growth rings are well-defined in some shrubby species distributed along the Patagonian steppe and provide useful information to identify the environmental factors that influence the radial growth of shrubs in the region. However, little is known about variations in ring width from these species and their relationships with local environment. In this paper we present 18 growth ring width chronologies covering the last 2–3 decades from the shrub Anarthrophyllum rigidum (Fabaceae) encompassing most of its natural range of distribution in Argentina. Interannual variations in growth were first analyzed collectively to identify common regional patterns. In addition, shrub growth at each site was compared with local climate records and site-specific characteristics. Based on a principal component analysis (PCA), sites were joined in four major groups related to the site proximity to the Andes (foothills versus Patagonian plateau) and latitude (north versus south Patagonia). The relatively similar percentage of PCA variance associated with each group reflects environmental differences among sites. Consistent with this observation, we noted large variability in the responses of the A. rigidum woody growth to regional climatic fluctuations. At most sites, this species is favored by abundant winter precipitation, warmer spring and autumn temperatures (controlling the duration of the growing season), cool summers, or a combination of these factors. However, deviations from these patterns are also recorded. Our study represents the first large-scale dendroclimatological analysis of a shrubby species in southern South America. The results presented here provide information on the main patterns and factors affecting the growth of A. rigidum in Patagonia, and may be useful for determining well-suited practices for management and conservation of this ubiquitous species. [Copyright &y& Elsevier]

The strong link between climate change and increased wildfire risk suggests a paradigm change on how humans must co-exist with fire and the environment. Different studies have demonstrated that human-induced fire ignitions can account for more than 90 % of forest fires, so human co-existence with wildfires requires informed decision making via preventive policies in order to minimize risk and adapt to new conditions. In this paper, we address the multidimensional effects of three groups of drivers (human activity, geographic and topographic, and land cover) that can be managed to assist in territorial planning under fire risk. We found critical factors of strong interactions with the potential to increase the likelihood of starting a fire. Our solution approach included the application of a Machine Learning method called Random Undersampling and Boosting (RUSBoost) to assess risk (fire occurrence probability), which was subsequently accompanied by a sensitivity analysis that revealed interactions of various levels of risk. The prediction performance of the proposed model was assessed using several statistical measures such as the Receiver Operating Characteristic curve (ROC) and the Area Under the Curve (AUC). The results confirmed the high accuracy of our model, with an AUC of 0.967 and an overall accuracy over test data of 93.01 % after applying a Bayesian approach for hyper-parameter optimization. The study area to test our solution approach comprised the entire geographical territory of central Chile. • Fire occurrence models can be used to inform preventive measures. • A fire occurrence model was developed that can help with territorial planning. • Risk thresholds are determined by human activity and land cover features. • Land cover types (natural or artificial) play an important role in fire ignition. • Four regions are delineated based on the interaction of the variables and fire risk. [ABSTRACT FROM AUTHOR]

Abstract: This paper suggests that Argentine and Chilean participation with the Antarctic section of the International Geophysical Year (IGY) of 1957–58 can be characterized as ‘reluctant collaboration.’ It then reflects on the implications of the nature of South American involvement for the history of the Antarctic section of the IGY, especially as it led to the negotiation of the 1959 Antarctic Treaty. During the initial planning stages of the IGY, both Argentina and Chile worried that proposals for widespread scientific research in the Antarctic continent would interfere with their contested claims to political sovereignty in the region. Yet despite their initial skepticism, Argentina and Chile found themselves swept along by the current of international scientific co-operation of the IGY, which persisted into the Antarctic Treaty negotiations of 1959. Within the limited options available, Chile and Argentina were able to negotiate an outcome that was not altogether unfavorable to their political interests. At the same time, their collaboration helped to legitimize both the IGY and the subsequent Antarctic Treaty. [Copyright &y& Elsevier]

Abstract: The southern fjord region of Chile is a unique ecosystem characterized by complex marine–terrestrial–atmospheric interactions that result in high biological production. Since organic nitrogen from terrestrial and atmospheric compartments is highly significant in this region (>40%), as is the low NO3:PO4 ratio in surface waters, it is suggested that fertilization from inorganic and organic nitrogen sources has a strong influence on both phytoplankton biomass/primary production and harmful algae bloom dynamics. The data presented in this paper provide an opportunity to improve our knowledge of phytoplankton dynamics on temporal and spatial mesoscales. Ocean color data from NASA (SeaWiFS) for chlorophyll and primary production estimates and in situ surface measurement of inorganic nutrients, phytoplankton biomass, and primary productivity revealed that the coastal waters of southern Chile have a classical spring and autumn chlorophyll bloom cycle in which primary production is co-limited by strong seasonal changes in light and nitrate. During spring blooms, autotrophic biomass (such as chlorophyll a, Chl-a) and primary production estimates reached 25mg Chl-a m−3 and 23mg Cm−3 h−1, respectively, and micro-phytoplankton accounted for a significant portion of the biomass (60%) in spring. The contribution of phytoplankton size classes to total chlorophyll a revealed the dominance of nanoplankton (>50%) in winter and post-bloom periods (<1.0mg Chl-a m−3). [Copyright &y& Elsevier]

Independent Component Analysis (ICA) is a statistical technique for decomposing information from datasets into maximally independent components. ICA allows the researcher to recover two or more independent signals that appear mixed within the same dataset. This paper shows ICA to be an extremely effective method for separating different colours found in rock paintings into discrete images or components. The comparison between the results of ICA and PCA (Principal Component Analysis) shows that ICA accurately separates panels with more than one type of colour, while PCA achieves a lower degree of separation. This study also shows that in scenes with monochrome depictions, ICA tends to be slightly more effective in separating the pigments from the rock. The ICA method has been applied successfully to several rock art panels from Northern Chile, where the use of diverse types of mineral pigments is common. Two analyses conducted at the Pampa El Muerto 11 site in the Northern Chilean highlands reveal how ICA can contribute to a more compelling interpretation of more intricate panels. The comparison between the results of ICA and PCA (Principal Components Analysis) shows that ICA correctly separates panels with more than one type of pigment, while PCA achieves a lower degree of separation. This study also shows that in scenes with monochrome depictions, ICA tends to be slightly more effective in separating the pigments from the rock. ICA algorithm has been successfully in several rock panels from Northern Chile, where the use of diverse types of mineral pigments is usual. Two panels from the Pampa El Muerto site have been analysed with the technique mentioned above, informing that its application can collaborate on a more compelling interpretation of intricate panels. • A new algorithm (FastICA) for enhancing of rock paintings in digital images is analysed. • FastICA can be a reliable solution for the analysis of panels with more than one shade of pigment and superimposition of depictions. • FastICA algorithm is more efficient in separating different colours than Principal Component Analysis (PCA). • We propose a protocol for the assessment of the outcomes of different algorithms. [ABSTRACT FROM AUTHOR]

Water scarcity is a global issue that is threatening social and economic development. One approach to alleviating scarcity is the incorporation of new water sources into supply systems, including desalinated seawater for industrial and municipal use. In Chile, large volumes of water are used in water-scarce regions where mining takes place, alongside agriculture and small communities. This situation has driven a debate around policies to increase the use of seawater to satisfy the water demand of the mining industry. The economic, social and environmental implications of such a policy, however, are poorly understood and the current regulatory framework to address concerns and uncertainties is inadequate. This paper presents a technical, legal, economic and environmental appraisal of such a policy and considers options to improve outcomes. The appraisal suggests that clear regulations derived from economic, social and environmental analysis must be generated to provide legal certainty and reduce risks. Alternative or complementary water supply options should be allowed where mining operations can demonstrate negligible hydrological and social impacts or use innovative solutions such as stakeholder water rights swaps and water efficiency technologies. We provide insight that will help to drive a better policymaking process aimed at tackling water scarcity in Chile and in similar areas of the world. • In Chile there is a drive to mandate seawater use in mining. • The implications of such a policy are poorly understood. • There are regulatory gaps that are causing widespread uncertainty. • The economic, environmental and social trade-offs could be damaging. • Further analysis and a more pragmatic approach is required that accounts for context. [ABSTRACT FROM AUTHOR]

This paper evaluates the impact of the Environmental Decontamination Plans (known as PDAs) on air quality in Chilean cities, for which the differences in differences method was used during the period between 2010 and 2017. The ex-post evaluation shows that the implementation of a PDA for PM 10 has no impact on the monthly concentrations of PM 10. However, the new PDAs for PM 2.5 (that were implemented starting in 2015) reduce the monthly concentrations of PM 10 by approximately 8 μg/m3, although they have not reduced the monthly concentrations of PM 2.5. Thus, it is concluded that the assumptions and scenarios used in the ex-ante evaluations to project the reduction of PM 2.5 concentrations in the PDAs are extremely optimistic in relation to their current contribution to improving air quality in Chile. • The impact of the Environmental Decontamination Plans (PDAs) is evaluated. • The differences in differences methodology is used. • There is limited effectiveness of the PDAs to reduce PM 2.5 concentrations. • The assumptions used in PDAs' ex-ante evaluations are extremely optimistic. • It is necessary to reformulate the PDAs applied in Chile. [ABSTRACT FROM AUTHOR]

The Chilean abalone or “loco” (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. [Copyright &y& Elsevier]