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... These variables were cut to the selected calibration area prior to model calibration. We also downloaded a global land cover use dataset at a spatial resolution of 1 km (Eva et al., 2003; https://forobs. jrc.ec.europa.eu/produ ...
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The Asian soybean stem borer Melanagromyza sojae (Zehntner) (Diptera: Agromyzidae) represents a threat to soybean and chickpea crops in South America. It is known that in the region its population has increased, in part, due to the difficulty in its agronomic management. This is due to the lack of knowledge regarding its biology and the environments that are favorable for its establishment. In this study, we provide a comprehensive database of records of M. sojae , as well as an updated list of its host plants from field surveys, bibliographic review, and online databases. We estimated the suitability and potential distribution of the pest considering environmental information from remote sensors and bioclimatic variables and contrasted these against land‐use cover across South America. In Argentina, M. sojae was found developing on Tithonia tubaeformis (Jacq.) Cass. (Asteraceae), surviving in chickpeas and volunteer soybeans that were affected by winter frost. The most informative models and highest suitability were predicted from vegetation indices and bioclimatic variables, and coincided with sites having a high proportion of arable land. Regarding climate, the greatest suitability occurred in eastern South America, including the southern states of Brazil and Paraguay, where the final models recovered the current known distribution of the species on the continent. However, its extension may be even greater than predicted, due to the wide distribution range of its hosts. This characterization of suitability for M. sojae could be a useful resource to anticipate the regions that are most favorable for its presence and supports the need to consider the distribution of crops and host plants that could act as natural reservoirs to identify sites and streamline efforts to reduce the incidence of the pest.
... Using QGIS 3.18.2-Zürich (Quantum GIS Development Team, 2021), these localities were plotted onto maps that describe the vegetation units present along Argentina and Chile (see Eva et al., 2002Eva et al., , 2004Luebert & Pliscoff, 2006;Oyarzabal et al., 2018), as well as the life zones and ecoregions occurring in both countries (see Morrone, 2015;Derguy et al., 2019;Derguy, Martinuzzi & Arturi, 2021). Localities were classified and grouped according to the vegetation physiognomy of the habitat present at each site, as the habitats of southern South American small-mammal species are more determined by the growth form of plants (i.e., vegetation physiognomy) than by plant species (i.e., taxonomic composition) that constitute the botanical community (Monjeau et al., 1997(Monjeau et al., , 1998. ...
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The relationship between phenotypic variation and landscape heterogeneity has been extensively studied to understand how the environment influences patterns of morphological variation and differentiation of populations. Several studies had partially addressed intraspecific variation in the sigmodontine rodent Abrothrix olivacea, focusing on the characterization of physiological aspects and cranial variation. However, these had been conducted based on geographically restricted populational samples, and in most cases, the aspects characterized were not explicitly contextualized with the environmental configurations in which the populations occurred. Here, the cranial variation of A. olivacea was characterized by recording twenty cranial measurements in 235 individuals from 64 localities in Argentina and Chile, which widely cover the geographic and environmental distribution of this species. The morphological variation was analyzed and ecogeographically contextualized using multivariate statistical analyses, which also included climatic and ecological variation at the localities where the individuals were sampled. Results indicate that the cranial variation of this species is mostly clustered in localized patterns associated to the types of environments, and that the levels of cranial differentiation are higher among the populations from arid and treeless zones. Additionally, the ecogeographical association of cranial size variation indicate that this species does not follow Bergmann’s rule and that island populations exhibit larger cranial sizes compared to their continental counterparts distributed at the same latitudes. These results suggest that cranial differentiation among the populations of this species is not homogeneous throughout its geographic distribution, and that the patterns of morphological differentiation are also not completely consistent with the patterns of genetic structuring that have been described recently. Finally, the analyses performed to ponder morphological differentiation among populations suggest that the contribution of genetic drift in the formation of these patterns can be ruled out among Patagonian populations, and that the selective effect imposed by the environment could better explain them.
... The default land use/land cover (LU/LC) input data for LOTOS-EUROS were derived from the Global Land Cover (GLC2000) project [48], which includes 23 categories consistent with the Land Cover Classification System of the Food and Agriculture Organization (FAO) classification. For South America, the mapping of these categories at spatial resolutions of 1 km x 1 km was done in [49], with contributions from some regional experts based on multi-resolution satellite data. In this work, the LU/LC data was updated with the 2009 Land Cover Climate Change Initiative (CCI) dataset [50], with 38 categories at a horizontal resolution of 300 m x 300 m. Figure 4 compares the default and updated LU/LC models for Aburrá Valley. ...
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This chapter book presents Medellín Air qUality Initiative or MAUI Project; it tells a brief story of this teamwork, their scientific and technological directions. The modeling work focuses on the ecosystems and human health impact due to the exposition of several pollutants transported from long-range places and deposited. For this objective, the WRF and LOTOS-EUROS were configurated and implemented over the región of interest previously updating some input conditions like land use and orography. By other side, a spinoff initiative named SimpleSpace was also born during this time, developing, through this instrumentation branch a very compact and modular low-cost sensor to deploy in new air quality networks over the study domain. For testing this instrument and find an alternative way to measure pollutants in the vertical layers, the Helicopter In-Situ Pollution Assessment Experiment HIPAE misión was developed to take data through the overflight of a helicopter over Medellín. From the data obtained from the Simple units and other experiments in the payload, a citogenotoxicity analysis quantify the cellular damage caused by the exposition of the pollutants.
... These wetlands not only contribute disproportionately to landscape-level diversity (Flinn et al., 2008), but are also complex ecosystems that are historically and ecologically related to both adjacent uplands (Ribeiro et al., 2013), as well as distant wetland areas (Lima and Ribeiro, 2011). Endemic species are scarce, and communities typically consist of widespread taxa, reaching their maximum level of diversity and abundance (Eva et al., 2002;Flinn et al., 2008;Albert and Reis, 2011;Lima and Ribeiro, 2011;Dagosta and de Pinna, 2019). Such distributional and macroecological attributes do not necessarily mean present-day hydrological connections, but past and eventually ephemeral connections along adjacent areas, including lowlands and uplands, over geological time scales. ...
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An alternative hypothesis concerning the paleoecological and paleoenvironmental depositional conditions of the Crato Konservat-Lagerstätte (CKL), Crato Formation, Aptian, NE Brazil, one of the most extraordinary Gondwana fossil sites, is proposed. Following an actualistic approach, the ecology of extant relatives of the most abundant and diverse fossil groups recorded in the CKL (i.e., vascular plants, arthropods, fishes, and tetrapods) is considered. Data is based on an extensive literature review followed by a re-examination of recently collected fossils. This approach allowed a detailed appraisal of the stratigraphic/ecological distribution of the main fossil groups preserved in the CKL. Plant and animal groups are recorded in three main stratigraphic intervals, named Intervals I–III in ascending order. Most fossils are to be considered autochthonous to parautochthonous and have been preserved in distinct stages of base-level fluctuations within a shallow lacustrine depositional system, subject to periodic flooding in large, depressed areas. Exceptional preservation in such environments was mediated by microbially-induced processes (i.e., microbial mat entombment), mostly in the coastal areas of the alkaline lake. Based on the distinct sedimentary facies and autecological attributes of dominant paleo-bioindicators, a new paleoenvironmental model for the CKL is proposed, encompassing a seasonal, semi-arid, shallow lacustrine wetland. Faunal and floral content were ecologically arranged in long-lasting aquatic zones, surrounded by periodically flooded mesophytic ecotones and outer xeric habitats, as in the modern alkaline lake Chad in Africa. Our data show the relevance of multiproxy analyses (i.e., paleontological, sedimentological, geochemical, and stratigraphic) of exceptional fossil sites for assessing paleoenvironmental conditions in depositional settings subject to continuous base-level changes, such as those existing in complex, present-day wetland ecosystems. The recognition of key parameters in ancient wetlands is of great importance concerning the formation of non-marine Konservat- Lagerstätten in the geological record.
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Agricultural irrigation practices can be a substantial proportion of the water budget in dryland environments. As the pressure on freshwater resources is growing in such environments, sustainable management of these resources is vital. Key issues need to be addressed: How does withdrawal for irrigation purposes alter a river’s flow regime and water yield? How can publicly available irrigation data help to improve the performance of hydrological models? A novel irrigation module was introduced to improve the performance of a mesoscale hydrological model (WASA-SED) and was tested on the hydrological upper meso-scale, as well as on a smaller subbasin in a semi-arid catchment in the Rio São Francisco basin. We could show that including irrigation practices into the modelling process especially helps to improve the quality of the modelled low flows during the dry season, where we achieved an improvement of the RMSE of up to 19%.
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Climate change is currently considered one key threat to biodiversity. Species with a restricted distribution possibly will be more affected than those with wide ranges. Climate change can potentially affect both herbivores and their host plants and reduce their geographical ranges. The nature and intensity of their responses, however, may not necessarily match. We investigated the synergistic effects of climate change on two Neotropical butterfly species and their respective host plants at the end of twenty-first century. The species selected contrast in distribution extent, feeding habits and conservation status: Battus polystictus is widespread, oligophagous and common and Parides ascanius has a restricted distribution, is monophagous and is listed as vulnerable in the IUCN red list. Maps of the potential distribution of the butterflies and their host plants, as well as maps showing the changes in the ranges, in overlap area and direction of shifts were produced. Under forecasted climate change, all ranges and interaction areas decreased and the impacts were proportional to the intensity of change in future scenarios, either when compared all together or pairwise (p < 0.001). Based in our results estimation of climatically suitability, the monophagous butterfly with restricted distribution did suffer more severely these effects than the widespread generalist species. We did not anticipate, however, the possible strength of the predicted effects. Under the conditions modelled, P. ascanius would probably find no suitable conditions for occurrence, irrespectively of its host plant, and might go extinct. B. polystictus, on the other hand, suffered marked decreases in suitable area (46% for RCP4.5 and 91% for RCP8.5) and dramatic southward shifts (> 1439 km for RCP4.5 and > 1956 km for RCP8.5) on its range. This effect is further worsening because although most host plants are also much affected by the changes, the shift in their ranges is on average much smaller and each species responded in subtly different ways to the changing conditions, so that most of their future range may be spatially incompatible with the B. polystictus. We propose that the extinction risk of P. ascanius should be adjusted to critically endangered and point that species interactions and climate change must be accounted for in conservation planning. Implications for insect conservation The assessment carried out in this study contributes to the knowledge of climate change scenarios of butterfly species correlated with their host plants until the end of this century. These results can propose priority sites for conservation efforts like contribute to change status of P. ascanius to critically endangered, actually listed as vulnerable on the IUCN red list.
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Over the last 50 years, studies have shown a decline in the use of mountain lands, a phenomenon termed land abandonment. We investigate the causal mechanisms of land use change in a mountain catchment important for regional water supplies in the southwestern Cape of South Africa. Uniquely, we include nature-based recreational land use types typically excluded from land abandonment studies. We repeated a structured questionnaire originally conducted with landowners 38 years previously and analysed orthoimages from 1948, 1972 and 2014. To identify and contextualise causal mechanisms of change we used thematic analysis and generated narratives from in-depth interviews with landowners. The land use system in 1948 and 1972 was dominated by livestock-based, subsistence agriculture and small-scale farming. This transitioned to agricultural intensification on the lowlands and small portions of the mountains and the utilisation of mountains for non-economic nature-based recreation and ecotourism. The use of frequent small, low intensity-controlled fires was prevalent in the past. More recently, fires have been actively suppressed resulting in the build-up of biomass and the development of infrequent, extensive, high-intensity wildfires. Land use change in the mountains was driven primarily by socio-economic drivers, including socio-economic benefits related to globalisation and economic growth, and not by concerns over land degradation or resource depletion. Our findings support evidence that shows that people’s responses to economic opportunities drive local determinants of land use change and highlights the importance of perceptions in driving land use transitions. We show that existing models of land abandonment are likely overly deterministic in that they do not consider social and cultural factors that may cause a landowner to continue using their land for semi-economic or non-economic reasons. While there is merit in large-scale remote sensing studies, we emphasise the importance of using mixed remote sensing and social science methods for informing models of land use change.
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Accurate characterization of tropical moist forest changes is needed to support conservation policies and to quantify their contribution to global carbon fluxes more effectively. We document, at pantropical scale, the extent and changes (degradation, deforestation, and recovery) of these forests over the past three decades. We estimate that 17% of tropical moist forests have disappeared since 1990 with a remaining area of 1071 million hectares in 2019, from which 10% are degraded. Our study underlines the importance of the degradation process in these ecosystems, in particular, as a precursor of deforestation, and in the recent increase in tropical moist forest disturbances (natural and anthropogenic degradation or deforestation). Without a reduction of the present disturbance rates, undisturbed forests will disappear entirely in large tropical humid regions by 2050. Our study suggests that reinforcing actions are needed to prevent the initial degradation that leads to forest clearance in 45% of the cases.
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There is growing consensus that land degradation assessments should occur at local to regional scales, as global assessments fail to capture the complexity of land degradation processes, and how they manifest in different social‐ecological contexts. We have tested a statistically rigorous method for regional land degradation assessment in drylands, using fuzzy classification theory and techniques, that results in the creation of a habitat condition archetype for the Namaqualand Hardeveld bioregion of the Succulent Karoo biome in South Africa. The methodology initially groups field data into classes based on known indicators of land degradation, before predicting observed field cover with 16 remote sensing variables, derived from both Landsat 8 and Sentinel‐2A satellite data. Using fuzzy classification techniques, projections of field cover from the resulting model are combined with variables representing a potential change in cover to produce a map of the habitat condition of the bioregion. Approximately 17% of the bioregion had habitat condition values less than one standard deviation smaller than the mean and could therefore be considered degraded. To provide context, this map is presented with potential drivers of change for the bioregion. The map, and accompanying drivers of change, are ultimately presented in a Google Earth Engine app for easy interpretation and use. This article is protected by copyright. All rights reserved.
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In this article we review the main characteristics of the Patagonian climate, the spatial and temporal patterns of the most important climatic variables, and the influence of climate on ecosystem processes. The winter distribution of precipitation determines an asynchrony between the wet and the growing season in Patagonia. The amount of water that can be transferred from the wet season to the growing season depends mainly on the physical characteristics of the soil. In the semiarid steppe of Chubut, drainage accounted for 10% of annual precipitation. Winter distribution of precipitation determines also an asynchronic dynamics of evaporation and transpiration fluxes. The ENSO phenomenon have a significant impact on regional precipitation. In central-west Patagonia, spring precipitation (September to November) was lower than normal during La Nina events and greater than normal during El Nino events. From December to February the opposite pattern can be observed: higher than normal precipitation during La Nina events and lower than normal precipitation during El Nino events. The impact of this phenomenon on the seasonal temperature was not as clear as for precipitation. We did not detect any temporal trends in annual precipitation for the period 1961-1996. The phenology of carbon gains is quite homogeneous in Patagonia. Most of the region showed a peak of production in November, when, simultaneously, water availability and temperature are high. Toward the west, production peaked later (December). Deciduous forests showed the peak in January and February.
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This paper presents, at regional level, a physionomic-floristic description of extra-andean Patagonia. We analysed the information with the greatest regional synthesis obtained in the last decades, specially the one that provided cartographic data. As a result of this synthesis, phytogeographical districts were subdivided, ecotones were delimited and boundaries were either confirmed or modified. The result is a map where we propose 16 physionomic-floristic units: 12 included in the six districts of the Patagonian province, two in the Monte province and two in ecotones. Existing phytosociological information has been added to the description of each unit.
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Prolonged seasonal drought affects most of the tropics, including vast areas presently or recently dominated by 'dry forests'. These forests have received scant attention, despite the fact that humans have used and changed them more than rain forests. This volume reviews the available information, often making contrasts with wetter forests. The world's dry forest heterogeneity of structure and function is shown regionally. In the neotropics, biogeographic patterns differ from those of wet forests, as does the spectrum of plant life-forms in terms of structure, physiology, phenology and reproduction. Biomass distribution, nutrient cycling, below-ground dynamics and nitrogen gas emission are also reviewed. Exploitation schemes are surveyed, and examples are given of non-timber product economies. It is hoped that this review will stimulate research leading to more conservative and productive management of dry forests.
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The geographical distribution of the different types of shrublands are summarised and the ecology of the area is outlined. The shrublands are a major biome, and one of the most diverse in the Guayana region, conclusions emphasised by discussion of physiognomy, floristics, ecology and vegetation dynamics. -S.J.Yates
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The Boreal Chaco is a part of the Gran Chaco covering half of the Republic of Paraguay. Climate, geology and vegetation are outlined. The vegetation of different regions are described with particular reference to their environmental conditions. Important differences exist between the zonal Chaco forest and the forests of the hills, swamps, dunes, and gallery forests. Rare components of the Chaco are sensitive to exploitation by man, in particular through deforestation and extensive exploitation and use of natural resources. -S.J.Yates
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Evaluates the resistence to flooding of the common trees in the Central Amazonian varzea forest. Plant distribution is described, in particular the low-lying shrub community and mid and high level tree community. The influence of sedimentation and erosion on the community structure is shown; these factors also affect diversity, dispersal and establishment of species. Morphological, anatomical and physiological adaptations of trees are noted. the annual floods cause the development of annual biorhythms which may have the same effect as the role performed by the light-temperature regime in high altitudes or by the change from the rainy to the dry season in the semi-tropics and sub-tropics. -S.J.Yates
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The temperate subhumid grasslands which cover the plains of C-eastern Argentina, Uruguay and S Brazil in an arc around the Rio de la Plata can be divided into the pampas and campos. Comments on the physical environment and on regionalisation are followed by description of the vegetation, distinguishing between the rolling pampa, flooding pampa, inland pampa, southern pampa, mesopotamic pampa, and southern and northern campos. While Poaceae dominate (many species of Stipa being found) the family Asteraceae also makes an important contribution to the flora. Structure and function of the grasslands are reviewed, with examination of phenology, primary production, plant community structure, energy flow, and response to water stress. Animal life is noted, with comments on conservation. Changes in land use, including the impact of agriculture, are also reported. -P.J.Jarvis
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The Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) has a unique capability to detect low levels of visible and near-infrared (VNIR) radiance at night. With the OLS 'VIS' band data, it is possible to detect clouds illuminated by moonlight, plus lights from cities, towns, industrial sites, gas flares, and ephemeral events such as fires and lightning illuminated clouds. This paper presents methods which have been developed for detecting and geolocating VNIR emission sources with nighttime DMSP-OLS data and the analysis of image time series to identify spatially stable emissions from cities, towns, and industrial sites. Results are presented for the United States.