Abstract:

Clearance for agriculture or cattle ranching was the dominant land-cover change during the last two decades in the South American Dry Chaco. The Argentinean portion has been particularly affected, presenting greater deforestation rates than the continental and global averages. Little is known on the control factors of the location and the spatial clearance patterns. In this article we studied (a) deforestation dynamics in the Argentinean Dry Chaco and the factors determining land clearing locations for the last 25 years; (b) changes in the relative impact of those factors through time and space; and (c) the effect of regulations aimed to control the location and magnitude of land transformation. We also tested the “expansion of the agricultural frontier” hypothesis for the Argentinean Chaco. To identify the factors that defined agricultural expansion we used binomial logistic models that were fitted to a set of independent variables (bio-physical, infrastructure and political factors) that could eventually influence the distribution of new agricultural areas. Results indicate that the Forest Law devised by the Argentinean federal government to control the clearing process was insufficient to restrict both the area transformed per year and clearance locations. Agriculture is expanding over marginal areas and land clearing dynamics have been increasingly associated to the proximity to already cleared areas, defining a frontier—advancement pattern which gives the idea of a contagion process. According to our results, the relative importance of the anthropic factors associated to the agricultural expansion in the region increased through time.

Author affiliation: Volante, Jose Norberto. INTA. Estación Experimental Agropecuaria Salta; Argentina

Author affiliation: Mosciaro, Maria Jesus. INTA. Estación Experimental Agropecuaria Salta.Laboratorio de Teledetección y SIG; Argentina

Author affiliation: Gavier Pizarro, Gregorio Ignacio. INTA. Instituto de Recursos Biológicos; Argentina

Author affiliation: Paruelo, José María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina

Abstract:

This paper studies the changes of groundwater, climate and land use in the Pampas of Argentina. These changes offer opportunities and threats. Lowering groundwater without irrigation causes drought and successive crop and yield damage. Rising groundwater may alleviate drought as capillary rise supports root water uptake and crop growth, thus narrowing the difference between potential and actual yields. However, rising groundwater may also limit soil water storage, cause flooding in metropolitan areas and have a negative impact on crop yields. Changing land use from continuous soy bean into crop rotations or natural vegetation may decrease groundwater recharge and thus decrease groundwater levels. In case of crop rotation however, leaching of nutrients like nitrate may increase. We quantified these impacts using integrated dynamic crop growth and soil hydrology modelling. The models were tested at field scale using a local dataset from Argentina. We applied distributed modelling at regional scale to evaluate the impacts on groundwater recharge and crop yields using long term weather data. The experiments showed that threats arise from continuous monotone land use. Opportunities are created when a proper balance is found between supply and demand of soil water using a larger differentiation of land use. Increasing the areas of land use types with higher evapotranspiration, like permanent grassland and trees, will contribute to a more stable hydrologic system with more water storage capacities in the soil system and lower groundwater levels. Modelling tools clearly support the evaluation of the impact of land use and climate change on groundwater levels and crop yields.

Instituto de Clima y Agua

Author affiliation: Kroes, Joop. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: van Dam, Jos. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: Supit, Iwan. Wageningen University and Research. Chair Water Systems and Global Change; Holanda

Author affiliation: De Abelleyra, Diego. INTA. Instituto de Clima y Agua; Argentina

Author affiliation: Veron, Santiago Ramón. INTA. Instituto de Clima y Agua; Argentina

Author affiliation: de Wit, Allard. Wageningen University and Research. Wageningen Environmental Research. Unit Earth Observation and Environmental Informatics; Holanda

Author affiliation: Boogaard, Hendrik. Wageningen University and Research. Wageningen Environmental Research. Unit Earth Observation and Environmental Informatics; Holanda

Author affiliation: Angelini, Marcos Esteban. INTA. Instituto de Suelos; Argentina. Wageningen University. Soil Geography and Landscape group; Holanda. International Soil Reference and Information Centre. World Soil Information; Holanda.

Author affiliation: Damiano, Francisco. INTA. Instuto de Clima y Agua; Argentina

Author affiliation: Groenendijk, Piet. Wageningen University and Research. Wageningen Environmental Research, Unit Sustainable Soil Use; Holanda

Author affiliation: Wesseling, Jan. Wageningen University and Research. Chair Soil Physics and Land Management; Holanda

Author affiliation: Veldhuizen, Ab. Wageningen University and Research. Wageningen Environmental Research. Unit Soil, Water and Land Dynamics; Holanda

Abstract:

El objetivo es analizar el banco de semillas del suelo (BSS) en un área de bosques nativos sujeta a cambio de uso de la tierra, y evaluar su rol en la regeneración de estos ecosistemas. Se evaluaron cuatro tratamientos: bosque nativo (BN), bosque nativo con manejo ganadero (BNM), bosque en regeneración (BR) y agricultura (AGR). La mayor densidad del BSS (11.917 semillas.m-2) se registró en BNM, correspondiendo a AGR el menor valor (3.142 semillas.m-2). Vachellia caven resultó la única especie arbórea representada en el banco, con densidades relativas inferiores al 1%. Las especies invasoras dominaron en todos los tratamientos, a excepción del BNM, que presentó mayor contribución de Gramíneas forrajeras. El 85% de las malezas determinadas en AGR fueron registradas en los otros tratamientos. El alto grado de fragmentación de los bosques nativos de la Cuenca, asociado al avance de la frontera agrícola, facilitaría el fl ujo de semillas de especies invasoras desde áreas agrícolas hacia los bosques circundantes, constituyendo otro de los impactos negativos de la deforestación.

The aim is to analyze the soil seed bank (SSB) in an area of native forests subject to change in land use and assess their role in natural regeneration of these ecosystems. Four treatments were evaluated: Native forest (NF), native forest in livestock management (NFM), regeneration forest (RF) and agriculture (AGR). The seed total density was significantly higher in NFM (11917seeds.m-2) than other treatments, corresponding to AGR the lowest value (3142seeds.m-2). Vachellia caven was the only tree species found, with values of relative density less than 1% in the forests evaluated. Weed species constituted the largest group of percentage contribution to SSB in all treatments, except NFM, dominated by Gramineae forage. The 85% of the weeds identified in AGR were found in the other treatments. The high degree of fragmentation of native forests, associated with the advance of the agricultural frontier, facilitate the seed flow of invasive species from agricultural areas into nearby forests, constituting one of the negative impacts of deforestation.

Author affiliation: Sione, Silvana María José. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina

Author affiliation: Ledesma, Silvia Gabriela. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina

Author affiliation: Rosenberger, Leandro Javier. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina

Author affiliation: Wilson, Marcelo German. INTA. Estación Experimental Agropecuaria Paraná; Argentina. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina

Author affiliation: Sabattini, Rafael Alberto. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias; Argentina

Abstract:

Land-use change driven by human population growth and economic activity will continue to impact both natural habitats and land currently being used for food, fiber, and fuel production. The effects of this conversion on economically important ecological services will in large part depend on how native biodiversity responds to these changes. We investigated how agriculture-related land use change influences the avian community in northeastern Argentina by examining common agricultural land uses (pasture/annual crops, young and mature large-scale eucalyptus plantations, mixed-use farms with citrus, blueberry and small stands of eucalyptus) and remnant native espinal savannas. In this region, afforested eucalyptus plantations represent a new land-use change from the land cover of pasture with intermixed annual crops that has dominated the region. In this mosaic, we used point counts to assess how avian diversity and community structure differed between land uses. Bird species richness was lowest in older plantations and highest in the espinal savanna, with the other land uses having intermediate richness. Abundance trends followed the same pattern, with low overall abundance in the plantations, intermediate levels for pasture/annual crops, and highest abundance in the espinal. Distinct bird community assemblages were strongly associated with each land use, and between young and mature eucalyptus stands. Birds can be useful indicators for biodiversity as a whole, and the depopulated and depauperate avian community within the eucalyptus plantations will likely lead to reduced provision of many ecosystem services in this region if the spatial extent of plantations continues to expand.

EEA Concordia

Author affiliation: Phifer, Colin C. Michigan Technological University. School of Forest Resources and Environmental Science; Estados Unidos

Author affiliation: Knowlton, Jessie L. Michigan Technological University. School of Forest Resources and Environmental Science; Estados Unidos

Author affiliation: Webster, Christopher R. Michigan Technological University. School of Forest Resources and Environmental Science; Estados

Author affiliation: Flaspohler, David J. Michigan Technological University. School of Forest Resources and Environmental Science; Estados

Author affiliation: Licata, Julián Andrés. INTA. Estación Experimental Agropecuaria Concordia; Argentina

Abstract:

In order to determine if intensive agricultural land use and/or edaphic characteristics modify the community of the arbuscular mycorrhizal fungi (AMF) indigenous of soils from the Argentinean Pampa; mycorrhizal colonization, sporulation, glomalin (GRSP) and genetic diversity were assessed. Soils were collected from seven localities from Buenos Aires Province (Argentina) under contrasting land use intensity (at each site both pristine and agricultural soils). The capacity for root colonization, sporulation and glomalin content of trap plants and growth substrate were considered as measure of AMF activity. Analysis of diversity was conducted using PCR-single strand conformation polymorphism (SSCP). Profiles were generated by using primers to amplify the 28S rDNA of AMF from rDNA extracted directly from the substrate of trap plant or AMF spore. Five bands of the SSCP gel were sequenced and showed similarity with the genus Glomus. Analysis of colonization and GRSP content, were not clearly related to the land use intensity but sporulation capacity was, in general, lower in agricultural soils than in pristine ones. Soil phosphorus, ferrum and zinc contents, were negatively related to the root colonization and sporulation capacities. High genetic diversity was found both from soil and spore samples. Although similar diversity was found under agricultural and pristine soils, in most sites SSCP-diversity was separately clustered by land use. Still remains clarify if soil characteristics, resulting from agricultural management; exert selection pressure on the AMF and whether they could be vectors of interest to select potential plant growth promoting microorganisms.

EEA Balcarce

Author affiliation: Thougnon Islas, Andrea Julieta. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina

Author affiliation: Hernández Guijarro, Keren. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina

Author affiliation: Eyherabide, Mercedes. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.

Author affiliation: Sainz Rozas, Hernan Rene. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Author affiliation: Echeverria, Hernan Eduardo. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina

Author affiliation: Covacevich, Fernanda. INTA. Estación Experimental Agropecuaria Balcarce. Unidad Integrada. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología; Argentina. Fundación para Investigaciones Biológicas Aplicadas; Argentina

Abstract:

Carbon emissions from land‐use changes in tropical dry forest systems are poorly understood, although they are likely globally significant. The South American Chaco has recently emerged as a hot spot of agricultural expansion and intensification, as cattle ranching and soybean cultivation expand into forests, and as soybean cultivation replaces grazing lands. Still, our knowledge of the rates and spatial patterns of these land‐use changes and how they affected carbon emissions remains partial. We used the Landsat satellite image archive to reconstruct land‐use change over the past 30 years and applied a carbon bookkeeping model to quantify how these changes affected carbon budgets. Between 1985 and 2013, more than 142 000 km2 of the Chaco's forests, equaling 20% of all forest, was replaced by croplands (38.9%) or grazing lands (61.1%). Of those grazing lands that existed in 1985, about 40% were subsequently converted to cropland. These land‐use changes resulted in substantial carbon emissions, totaling 824 Tg C between 1985 and 2013, and 46.2 Tg C for 2013 alone. The majority of these emissions came from forest‐to‐grazing‐land conversions (68%), but post‐deforestation land‐use change triggered an additional 52.6 Tg C. Although tropical dry forests are less carbon‐dense than moist tropical forests, carbon emissions from land‐use change in the Chaco were similar in magnitude to those from other major tropical deforestation frontiers. Our study thus highlights the urgent need for an improved monitoring of the often overlooked tropical dry forests and savannas, and more broadly speaking the value of the Landsat image archive for quantifying carbon fluxes from land change.

Instituto de Recursos Biológicos

Author affiliation: Baumann, Matthias. Humboldt-University Berlin. Geography Department; Alemania

Author affiliation: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentina. Humboldt-University Berlin. Integrative Research Institute for Transformations in Human Environment Systems; Alemania

Author affiliation: Piquer Rodriguez, María. Humboldt-University Berlin. Geography Department; Alemania

Author affiliation: Gavier Pizarro, Gregorio Ignacio. INTA. Instituto de Recursos Biológicos; Argentina

Author affiliation: Griffiths, Patrick. Humboldt-University Berlin. Geography Department; Alemania

Author affiliation: Hostert, Patrick. Humboldt-University Berlin. Geography Department; Alemania. Humboldt-University Berlin. Integrative Research Institute for Transformations in Human Environment Systems; Alemania

Author affiliation: Kuemmerle, Tobias. Humboldt-University Berlin. Geography Department; Alemania. Humboldt-University Berlin. Integrative Research Institute for Transformations in Human Environment Systems; Alemania

Abstract:

Las prácticas de conservación agrícola y diversos sistemas de producción tradicionales pueden incrementar considerablemente el carbono orgánico en suelos. Con el objetivo de evaluar la acumulación de carbono en biomasa de raíces y hojarasca con diferentes usos del suelo, se realizó un ensayo en el oeste de la provincia del Chaco, Argentina. Los usos de la tierra (tratamientos) evaluados fueron: pastizal natural, pastura implantada, sistema silvopastoril, bosque nativo semiárido y campo agrícola. Se realizaron calicatas a lo largo de una transecta y se muestrearon los estratos: 0-0,05; 0,05- 0,15; 0,15-0,3; 0,3-0,6 m. Se utilizó un diseño en bloques completos al azar con 3 repeticiones. Los resultados fueron analizados con ANOVA y Test de Tukey (p ≤ 0,05). El carbono en hojarasca fue mayor en la pastura (670,7 kg ha-1) y en el sistema silvopastoril (944,1 kg ha-1) comparado con el pastizal, el bosque nativo y el campo agrícola, que registraron valores de 300,3 kg ha-1; 200,3 kg ha-1; y 500,24 kg ha-1, respectivamente. El aporte de carbono de las raíces fue mayor en los dos primeros estratos muestreados (0-0,05m y 0,05-0,15 m). El uso de bosque nativo registró valores de 3156,9 y 2779,2 kg ha-1, mientras que el sistema silvopastoril alcanzó 2448,4 y 1228,9 kg ha-1 a los 0,05 m y 0,15 m de profundidad, respectivamente. Estos dos usos son los que registraron el mayor aporte de carbono por raíces.

Agricultural conservation practices and various traditional production systems can significantly increase organic carbon in soils. A study was carried out in order to evaluate the accumulation of carbon in root and litter biomass with different land uses. The essay was conducted in the west of the Chaco province, Argentina. The following land uses (treatments) were evaluated: natural grassland, pasture, silvopastoral system, semi-arid native forest and cultivated field. Pits were made along a transect and the following strata were sampled: 0 to 0.05; 0.05 to 0.15; 0.15 to 0.3; and 0.3 to 0.6 m. A randomized complete block design was used, with 3 replicates. The results were analyzed with ANOVA and Tukey test (p ≤ 0.05). Litter carbon was higher in the pasture (670.7 kg ha-1) and silvopastoral system (944.1 kg ha-1) compared to values recorded in the natural grassland, native forest and cultivated field, which reached 300.3 kg ha-1; 200.3 kg ha-1; and 500.24 kg ha-1, respectively. The carbon contribution from the roots was greater in the first two strata sampled (0 to 0.05m and 0.05 to 0.15m). The native forest recorded values of 3156.9 and 2779.2 kg ha-1, while the silvopastoral system reached values of 2448.4 and 1228.9 kg ha-1 at 0.05 m and 0.15 m depth, respectively. These two land uses recorded the highest root contributions of carbon.

EEA Colonia Benitez

Author affiliation: Cespedes Flores, Flora Elizabet. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina. INTA. Estación Experimental Agropecuaria Colonia Benítez; Argentina

Author affiliation: Fernandez, Juan A. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina

Author affiliation: Giménez, Laura. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina

Author affiliation: Leonhardt, Edgardo Aldo Alberto. INTA. Estación Experimental Agropecuaria Sáenz Peña. Agencia de Extensión Rural Pampa del Infierno; Argentina

Author affiliation: Bernardis, Aldo Ceferino. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina

Abstract:

Considering uncertainties regarding climate variability, the objective of this study was to make a long-term (1901–2011) comparative assessment of the impact of land-use decision (changes in the cultivated area) and technology adoption as adaptative mechanisms of the rural sector in the Argentine Chaco and the US Southern Plains. Different sources of data on climate (precipitation, minimum, mean and maximum temperature and evapotranspiration), land-use change (proportion of cultivated area) and technology adoption were used. This work involved three main analytical steps: i) Principal Components Analysis (PCA) was applied to identified the dominant components of data variance, ii) the relationship between the residuals of precipitation and land-use change was assessed by means of a simple regression analysis and iii) technology adoption was evaluated through a proxy based on historical changes in the yield of maize (Zea mays L.). The results showed that farmers in both countries relied on two common adaptative strategies to face climate perturbations during the study period: i) land-use change (a simple binary decision of planting or not planting in response to climate conditions) during a first stage, and ii) the introduction of adaptative technologies to smooth the impact of climate during the second one. That substitution of adaptative strategies begun during the 1940 decade in the US Southern Plains, and around 30 years later in the Argentine Chaco. The adoption of technologies and agronomic practices explained the sensitivity decay of the cultivated area to the climatic variability during the second stage. The incorporation of improved hybrids with higher drought resistance plus the adoption of tilling practices like minimum tillage or no-till, the input of fertilizers, pesticides and irrigation water (the last one in US, only) became a successful strategy to mitigate the risk of climate perturbation.

EEA Anguil

Author affiliation: Ricard, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina

Author affiliation: Viglizzo, Ernesto Francisco. INTA. Estación Experimental Agropecuaria Anguil; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; Argentina

Author affiliation: Podestá, Guillermo Pablo. University of Miami. Rosenstiel School of Marine and Atmospheric Science. Division of Meteorology and Physical Oceanography; Estados Unidos

Abstract:

p.235-243

Este trabajo propone una aproximación metodológica para la planificación regional a través del análisis de los condicionantes topográficos y del uso de la tierra. Los análisis topográficos presentan la ventaja de evaluar la dirección, acumulación y velocidad relativa de la escorrentía potencial. El objetivo del trabajo es generar un modelo espacial para caracterizar la morfodinámica del paisaje de la cuenca del Arroyo del Tala de la provincia de Buenos Aires. Se aplicó la técnica de sistemas de información geográfica (SIG) en la cuenca. Entre los resultados se observó que la densidad de líneas de drenaje es máxima en la porción media e inferior de la cuenca. En lanaciente y algunos pocos sectores medios, el drenaje es difuso; sin embargo, esta controlado mediante zanjas. El modelo espacial obtenido integra y jerarquiza una amplia zona de acumulación en el tercio superior de la cuenca, además de la llanura de inundación y a una pequeña zona de acumulación al norte del tercio inferior. La zona por debajo de los 15 m snm representaría el área de acumulación de toda la cuenca.

Abstract:

En la región semiárida pampeana el intervalo hídrico óptimo (IHO) no ha sido utilizado para valorar cambios en la calidad del suelo relacionados al manejo. El objetivo del trabajo fue caracterizar y evaluar el IHO en un suelo bajo uso en vegetación natural con gramíneas perennes (VN) y bajo uso agrícola (A). El estudio se desarrolló en Paleustoles petrocálcicos de la planicie con tosca de la Región Semiárida Pampeana Central. En un suelo VN y otro bajo uso A, y en estrato superior, medio e inferior del perfil respectivamente, se determinó, arcilla, limo, porosidad total, contenido de carbono, nitrógeno y el IHO. El uso A condicionó los valores del IHO en los dos primeros estratos y presentó mayores diferencias entre profundidades con respecto al suelo en VN. Los valores promedios del IHO para el suelo VN fueron 0,14; 0,15 y 0,15 cm3 cm-3 y en el suelo A de 0,06, 0,01 y 0,18 cm3 cm-3 en estratos superior, medio e inferior respectivamente. En ambos usos, el límite húmedo del IHO fue el contenido hídrico en capacidad de campo. El límite seco en el suelo A lo representó la curva de resistencia a la penetración, en cambio en el suelo VN el límite seco correspondió a la curva de punto de marchitez. Se observó que el IHO correlacionó con carbono y nitrógeno en el estrato superior e inferior, mientras que en el estrato medio del perfil esta relación no fue importante. En general se puede inferir que el intervalo hídrico óptimo fue un indicador sensible que reflejó los cambios en el sistema poroso del suelo bajo el uso agrícola con respecto a un suelo de similar textura bajo vegetación natural.

The Least Limiting Water Range (IHO) has not been used in the semiarid Pampas to describe the soil quality changes related to management. The objective of this work was to characterize and evaluate the IHO in soils under natural grassland vegetation (VN) and agriculture (A). The study was carried out on petrocalcic Paleustolls in the calcic plains of the central semiarid Pampas. Clay and silt, carbon and nitrogen contents, total porosity and IHO were determined on samples from upper, medium, and lower soil profile layers of a VN and an A soil. Agriculture affected IHO in the upper and medium layer, and showed more differences among layers than VN. Average IHO values for VN were 0.14, 0.15 y 0.15 cm3 cm-3, and 0.06, 0.01 y 0.18 cm3 cm-3 in the A soil for the upper, medium and lower layers, respectively. In both soils the IHO moist limit was determined by field capacity moisture contents, whereas the dry limit was defined by the penetration resistance curve in A and by the permanent wilting point moisture in VN. A positive relation between IHO and total soil carbon and nitrogen was observed for the upper and lower depth layers, while in the medium depth layer this relationship was not important. In general terms, it is concluded that the Least Limiting Water Range was a sensitive indicator which reflected the changes in the soil porous system under agricultural use compared to a soil with similar texture under natural vegetation.

EEA Anguil

Author affiliation: Fernandez, Romina. INTA. Estación Experimental Agropecuaria Anguil; Argentina

Author affiliation: Quiroga, Alberto Raul. INTA. Estación Experimental Agropecuaria Anguil; Argentina. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina

Author affiliation: Lobartini, Juan Carlos. Universidad Nacional del Sur. Departamento de Agronomía; Argentina

Author affiliation: Noellemeyer, Elke. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina