The challenge of making the idea of Sustainable Intensification operational

The intensification of agricultural production has become a topic of intense debate in academic and socio-political media worldwide. In southern South America agricultural intensification operates in two ways. On one hand, through the rThe intensification of agricultural production has become a topic of intense debate in academic and socio-political media worldwide. In southern South America agricultural intensification operates in two ways. On one hand, through the replacement of natural covers (forests and native grasslands dedicated, in general, to livestock) by annual or perennial crops (in general soybeans or pine and eucalyptus plantations). On the other hand, intensification is associated with the increasing input use and/or the implementation of management practices that increase production per area unit.eplacement of natural covers (forests and native grasslands dedicated, in general, to livestock) by annual or perennial crops (in general soybeans or pine and eucalyptus plantations). On the other hand, intensification is associated with the increasing input use and/or the implementation of management practices that increase production per area unit.Fil: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de la República; Urugua

Los sistemas agropecuarios : qué verde era mi valle

Fil: Paruelo, José. Universidad de Buenos Aires. Facultad de Agronomía; Argentina.La agricultura es una de las actividades humanas que contribuyen a\ngenerar cambios de escala global al modificar el tipo de cobertura y el\nuso del suelo. Al sustituir bosques por cultivos, por ejemplo, se ve\nafectada la diversidad biótica por pérdida de especies. Así se modifica\nla dinámica del carbono (C) de la porción deforestada, con un aumento\nen la cantidad de C atmosférico por mayores pérdidas y menor\nincorporación.\nLa agricultura no solamente contribuye a los cambios globales, también\nse ve afectada por éstos, al modificarse el régimen de lluvias y por el\naumento en la temperatura global

Land use / land cover change (2000 – 2014) in the Rio de la Plata grasslands : an analysis based on MODIS NDVI time series

Baeza, Santiago. Universidad de la República. Facultad de Agronomía. Departamento de Sistemas Ambientales. Montevideo, Uruguay.Paruelo, José María. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Laboratorio de Análisis Regional y Teledetección (LART) Buenos Aires, Argentina.22Latin America in general and the Rio de la Plata Grasslands (RPG) in particular, are one of the regions in the world with the highest rates of change in land use/land cover (LULC) in recent times. Despite the magnitude of this change process, LULC descriptions in the RPG are far from being complete, even more those that evaluate LULC change through time. In this work we described LULC and its changes over time for the first 14 years of the 21st century and for the entire grassland biome of the Rio de la Plata, one of the most extensive grassland regions in the world. We performed simple but exhaustive classifications at regional level based on vegetation phenology, using extensive LULC field database, time series of MODIS NDVI satellite images and decision trees classifiers, generating an annual map for all RPG. The used technique achieved very good levels of accuracy at the regional (94.3%–95.5%) and sub-regional (78.2%–97.6%) scales, with commission and omission errors generally low (Min = 0.6, Max = 10.3, Median = 5.7, and Min = 0, Max = 41.8, Median = 6.8 for regional and sub regional classification respectively) and evenly distributed, but fails when LULC classifications are generated in years when the climate is very dierent from those used to generate spectral signatures and train decision trees, or when the NDVI time series accumulates large volumes of lost data. Our results show that the RPG are immersed in a strong process of land use change, mainly due to the advance of the agricultural frontier and at the expense of loss of grassland areas. The agricultural area increased 23% in the analyzed period, adding over than 50,000 Km2 of new crops. Most agricultural expansion, and therefore the greatest losses of grassland, concentrates on both sides of Uruguay river (Mesopotamic Pampa and the western portion of Southern and Northern Campos) and the western portion of Inland Pampa. The generated maps open the door for more detailed and spatially explicit modeling of many important aspects of ecosystem functioning, for quantification in the provision of ecosystem services and for more efficient management of natural resources

Disentangling the signal of climatic fluctuations from land use : changes in ecosystem functioning in South American protected areas (1982-2012)

177-189Global environmental change is characterized by changing climate, atmospheric composition and land use. Its impact on ecosystem structure and functioning has been detected throughout the world. While every ecosystem is vulnerable to climate change, the degree of the impact and the magnitude of the ecosystem response are likely to vary. Protected areas of South America provide a ‘laboratory’ to test expectations of climate change effects on ecosystems at a regional scale. By using protected areas we minimized the effects of land use/land cover changes over ecosystem functioning. We analyzed the temporal trends, that is, directional changes, and spatial heterogeneity of both climatic variables and attributes of the seasonal dynamics of the normalized difference vegetation index, that is, a surrogate of vegetation carbon gains derived from satellite information, on 201 protected areas of South America. Increased productivity and higher seasonality, frequently climate driven, is the most common signal across South American biomes but concentrated on those areas located in the tropics and subtropics. In general, arid and semiarid sites responded positively to increases in precipitation and negatively to increases in temperature, while humid ecosystems responded in the opposite way. Our results provide a preliminary basis for predicting which ecosystems will respond more rapidly and strongly to climate change. We also provide support to the fact that protected areas are not static systems as their functioning is changing with different magnitude and in contrasting directions

Projected land-cover changes and their consequences on the supply of Ecosystem Services in Uruguay

Grasslands are one of the most human-modified biomes in the world due to the expansion of croplands and afforestation. In the scenario of productive intensification, it is necessary to generate alternatives to model land-cover changes and their environmental consequences. The objective of this study was to generate land-cover projections and quantify the future impact of these dynamics on the supply of ecosystem services in Uruguay. For that, land-cover maps, Markov-chains models, and an index of the supply of ecosystem services (ESSI) were utilized. Based on the land-cover maps, transitions probabilities between classes for two time periods (2000–2010 and 2010-2019) were calculated, and two Markovian-chain models were performed. With the projected land-cover maps, spatial models were used to relate the proportion of croplands and grasslands with the ESSI. The results indicate a continuous increase of croplands and afforestation for the next decade. Grasslands will remain the most abundant land-cover, reaching 46% in 2037. The highest probability of persistence was, in both periods, for grasslands, while the probability of persistence increased by 60 and 13% for croplands and afforestation, respectively. The ESSI shows a 5% of decrease between 2000-2037. These findings provide important empirical evidence for territorial planning and sustainable management.Agencia Nacional de Investigación e Innovació

Bricks or people? Investing more and better in Science, a dilemma for South American countries

Productivity of the Science and Technology (S&T) sector of Latin American countries would require more public and private investment to increase. Despite significant progress in the first 15 years of this century, South American investment in Science as percentage of GDP has been 10fold lower than that of Europe. Though the need to increase S&T investment is clear, less obvious is whether money should go to infrastructure or human capital. Using global databases we assessed scientific productivity, number of researchers and resources devoted to S&T. We evaluated production for Europe, the Americas and China. We then focused on three Mercosur countries: Argentina, Brazil and Uruguay. Scientific production was related to S&T expenditure and to the number of researchers. We found that countries investing ~2% of their GDP may have a 5-fold variation in their productivity. Our results suggest that human capital explains a higher proportion of the S&T productivity than the total amount of resources devoted to science. Thus, people would matter more than infrastructure in determining the scientific output. The positive trends in the resources devoted to Science in Argentina, Brazil and Uruguay do not allow, though, to reach in a decade the levels of productivity of European countries

Disentangling the signal of climatic fluctuations from land use: changes in ecosystem functioning in South American protected areas (1982-2012)

Global environmental change is characterized by changing climate, atmospheric composition and land use. Its impact on ecosystem structure and functioning has been detected throughout the world. While every ecosystem is vulnerable to climate change, the degree of the impact and the magnitude of the ecosystem response are likely to vary. Protected areas of South America provide a ‘laboratory’ to test expectations of climate change effects on ecosystems at a regional scale. By using protected areas we minimized the effects of land use/land cover changes over ecosystem functioning. We analyzed the temporal trends, that is, directional changes, and spatial heterogeneity of both climatic variables and attributes of the seasonal dynamics of the normalized difference vegetation index, that is, a surrogate of vegetation carbon gains derived from satellite information, on 201 protected areas of South America. Increased productivity and higher seasonality, frequently climate driven, is the most common signal across South American biomes but concentrated on those areas located in the tropics and subtropics. In general, arid and semiarid sites responded positively to increases in precipitation and negatively to increases in temperature, while humid ecosystems responded in the opposite way. Our results provide a preliminary basis for predicting which ecosystems will respond more rapidly and strongly to climate change. We also provide support to the fact that protected areas are not static systems as their functioning is changing with different magnitude and in contrasting directions

Environmental and Human Controls of Ecosystem Functional Diversity in Temperate South America

The regional controls of biodiversity patterns have been traditionally evaluated using structural and compositional components at the species level, but evaluation of the functional component at the ecosystem level is still scarce. During the last decades, the role of ecosystem functioning in management and conservation has increased. Our aim was to use satellite-derived Ecosystem Functional Types (EFTs, patches of the land-surface with similar carbon gain dynamics) to characterize the regional patterns of ecosystem functional diversity and to evaluate the environmental and human controls that determine EFT richness across natural and human-modified systems in temperate South America. The EFT identification was based on three descriptors of carbon gain dynamics derived from seasonal curves of the MODIS Enhanced Vegetation Index (EVI): annual mean (surrogate of primary production), seasonal coefficient of variation (indicator of seasonality) and date of maximum EVI (descriptor of phenology). As observed for species richness in the southern hemisphere, water availability, not energy, emerged as the main climatic driver of EFT richness in natural areas of temperate South America. In anthropogenic areas, the role of both water and energy decreased and increasing human intervention increased richness at low levels of human influence, but decreased richness at high levels of human influence

Caracterización regional de la estructura y de la productividad de la vegetación de la Puna mediante el uso de imágenes MODIS

La Puna es una región semiárida ubicada por encima de los 3300 msnm. en el noroeste argentino. Si bien existen descripciones florísticas parciales de la vegetación en el área, no existen trabajos que describan su fisonomía y su funcionamiento, aspectos claves para el manejo de la vegetación de la región. El objetivo de este trabajo fue cartografiar los diferentes tipos fisonómicos presentes y caracterizar su funcionamiento a partir de la estimación de la productividad primaria neta aérea (PPNA) en un área de 69210 km2 en las provincias de Salta y Jujuy. La aproximación metodológica combinó la utilización de datos provistos por sensores remotos, modelos biofísicos para estimar la productividad y censos fisonómico - florísticos. De las clases vegetadas, las estepas arbustivas (Estepa arbustiva densa y Estepa arbustiva rala) fueron las que ocuparon mayor proporción del territorio analizado, cubriendo entre ambas el 45% aproximadamente, mientras que las Estepas graminosas densas fueron las menos representadas, cubriendo poco más del 1%. Entre las clases no vegetadas el Suelo desnudo fue la clase más extendida, cubriendo aproximadamente 30% del área, seguida por la clase Salar, que ocupó 8.15%. El tipo fisonómico más productivo fue la Estepa graminosa densa (PPNA = 3900 kg MS/ha.año), mientras que la Estepa arbustiva rala presentó la menor productividad (PPNA = 472 kg MS/ha.año). Los restantes tipos fisonómicos no superaron en promedio los 1000 kg MS/ha.año.Fil: Baldassini, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Volante, José Norberto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; ArgentinaFil: Califano, Mariana Lujan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Oficina de Información Técnica Humahuaca; ArgentinaFil: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentin