Aplicação de análise multicriterial para determinação de áreas prioritárias à recomposição florestal

Using the Geographic Information System (GIS) and taking into account its capability to analyze spatial data, a database of updated spatial data from the sub-basin of the Descalvado stream, Botucatu, SP, was developed to provide an evaluation and diagnosis of the area concerning land use and the degradation processes therein. Through GIS, priority areas for forest recovery were defined by Multicriteria Evaluation and using the Ordered Weighted Average method. The latter allows the decision maker to define the area to be recovered, facing limitation of resources, among one of the proposed scenarios, or do it in stages. The study showed that there are accelerated erosion processes in the headwaters of the springs of water bodies; there is also fragmentation of native vegetation, especially in hillside areas, and little presence of native vegetation in riparian areas. The application of the multicriteria analysis using the Ordered Weighted Average was important as it systematized and discriminated scenarios of priority for forest recovery.

Identificação de áreas degradadas por extração de argila no município de Ourinhos (SP): recuperação do passivo ambiental e proteção dos recursos hídricos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análisis espacio-temporal de las praderas de Cymodocea nodosa (Ucria) Ascherson en la isla de Gran Canaria

Máster Oficial en Gestión Costera

Landwirtschaftliche Schaderregerprognose mit Hilfe von geographischen Informationssystemen

In der hier vorliegenden Arbeit wurde am Beispiel der Kraut- und Knollenfäule an Kartoffeln Phytophthora infestans und des Kartoffelkäfers Leptinotarsa decemlineata untersucht, ob durch den Einsatz von Geographischen Informationssystemen (GIS) landwirtschaftliche Schader¬reger¬prognosen für jeden beliebigen Kartoffelschlag in Deutschland erstellt werden können. Um dieses Ziel zu erreichen, wurden die Eingangsparameter (Temperatur und relative Luftfeuchte) der Prognosemodelle für die beiden Schaderreger (SIMLEP1, SIMPHYT1, SIMPHYT3 and SIMBLIGHT1) so aufbereitet, dass Wetterdaten flächendeckend für Deutschland zur Verfügung standen. Bevor jedoch interpoliert werden konnte, wurde eine Regionalisierung von Deutschland in Interpolationszonen durchgeführt und somit Naturräume geschaffen, die einen Vergleich und eine Bewertung der in ihnen liegenden Wetterstationen zulassen. Hierzu wurden die Boden-Klima-Regionen von SCHULZKE und KAULE (2000) modifiziert, an das Wetterstationsnetz angepasst und mit 5 bis 10 km breiten Pufferzonen an der Grenze der Interpolationszonen versehen, um die Wetterstationen so häufig wie möglich verwenden zu können. Für die Interpolation der Wetterdaten wurde das Verfahren der multiplen Regression gewählt, weil dieses im Vergleich zu anderen Verfahren die geringsten Abweichungen zwischen interpolierten und gemessenen Daten aufwies und den technischen Anforderungen am besten entsprach. Für 99 % aller Werte konnten bei der Temperaturberechnung Abweichungen in einem Bereich zwischen -2,5 und 2,5 °C erzielt werden. Bei der Berechnung der relativen Luftfeuchte wurden Abweichungen zwischen -12 und 10 % relativer Luftfeuchte erreicht. Die Mittelwerte der Abweichungen lagen bei der Temperatur bei 0,1 °C und bei der relativen Luftfeuchte bei -1,8 %. Zur Überprüfung der Trefferquoten der Modelle beim Betrieb mit interpolierten Wetterdaten wurden Felderhebungsdaten aus den Jahren 2000 bis 2007 zum Erstauftreten der Kraut- und Knollenfäule sowie des Kartoffelkäfers verwendet. Dabei konnten mit interpolierten Wetterdaten die gleichen und auch höhere Trefferquoten erreicht werden, als mit der bisherigen Berechnungsmethode. Beispielsweise erzielte die Berechnung des Erstauftretens von P. infestans durch das Modell SIMBLIGHT1 mit interpolierten Wetterdaten im Schnitt drei Tage geringere Abweichungen im Vergleich zu den Berechnungen ohne GIS. Um die Auswirkungen interpretieren zu können, die durch Abweichungen der Temperatur und der relativen Luftfeuchte entstanden wurde zusätzlich eine Sensitivitätsanalyse zur Temperatur und relativen Luftfeuchte der verwendeten Prognosemodelle durchgeführt. Die Temperatur hatte bei allen Modellen nur einen geringen Einfluss auf das Prognoseergebnis. Veränderungen der relativen Luftfeuchte haben sich dagegen deutlich stärker ausgewirkt. So lag bei SIMBLIGHT1 die Abweichung durch eine stündliche Veränderung der relativen Luftfeuchte (± 6 %) bei maximal 27 Tagen, wogegen stündliche Veränderungen der Temperatur (± 2 °C) eine Abweichung von maximal 10 Tagen ausmachten. Die Ergebnisse dieser Arbeit zeigen, dass durch die Verwendung von GIS mindestens die gleichen und auch höhere Trefferquoten bei Schaderregerprognosen erzielt werden als mit der bisherigen Verwendung von Daten einer nahegelegenen Wetterstation. Die Ergebnisse stellen einen wesentlichen Fortschritt für die landwirtschaftlichen Schaderregerprognosen dar. Erstmals ist es möglich, bundesweite Prognosen für jeden beliebigen Kartoffelschlag zur Bekämpfung von Schädlingen in der Landwirtschaft bereit zu stellen.

Le campagne di Piacenza tra VII e IX secolo: insediamenti e comunità

Al centro della seguente ricerca c'è il Piacentino, ossia il territorio che faceva capo alla città di Placentia in età altomedievale, più precisamente tra VII e IX secolo. L'aspetto su cui è concentrata l’analisi è quello dell’insediamento, rapportando le forme insediative alle comunità rurali e alle strutture del potere. Il Piacentino costituisce un contesto particolare, sia per la vicinanza alla capitale Pavia, sia per la presenza di enti patrimoniali molto importanti, quale il monastero di Bobbio, sia per l'estensione di vallate appenniniche che ne hanno protetto l'isolamento e impedito, fino al secolo IX inoltrato, l'insediamento di una forte aristocrazia. Ciò che sembra dedursi dall’analisi della documentazione (informatizzata) di VIII, ma soprattutto di IX secolo, è che la civitas di Piacenza, sede del conte e centro della diocesi, non costituiva di fatto il punto di riferimento per gli abitanti dell’intero territorio rurale. Dal punto di vista del possesso fondiario molti insediamenti erano autonomi. Ciò vale soprattutto per i siti di alcune zone collinari e per quelli dell’Appennino, mentre il discorso è da porsi in modo più sfumato per la pianura e per la zona dei prata vel campanea Placentina, ubicati immediatamente al di fuori della civitas. Lo studio della media e grande proprietà fondiaria ha permesso di registrare la frammentarietà dei possedimenti, ossia la loro dispersione nel sistema insediativo del comitato, la loro ubicazione e l’articolato intreccio proprietario, che in alcune zone sembra avere permesso l’esistenza di comunità locali piuttosto forti. L’attento esame della documentazione e il sicuro rimando alla bibliografia di riferimento hanno portato a risultati originali e significativi.

Un modello multicriteriale di supporto alla pianificazione territoriale finalizzato alla classificazione del territorio rurale e alla caratterizzazione dell’Impronta Agro ambientale delle aree agricole periurbane.

La ricerca proposta si pone l’obiettivo di definire e sperimentare un metodo per un’articolata e sistematica lettura del territorio rurale, che, oltre ad ampliare la conoscenza del territorio, sia di supporto ai processi di pianificazione paesaggistici ed urbanistici e all’attuazione delle politiche agricole e di sviluppo rurale. Un’approfondita disamina dello stato dell’arte riguardante l’evoluzione del processo di urbanizzazione e le conseguenze dello stesso in Italia e in Europa, oltre che del quadro delle politiche territoriali locali nell’ambito del tema specifico dello spazio rurale e periurbano, hanno reso possibile, insieme a una dettagliata analisi delle principali metodologie di analisi territoriale presenti in letteratura, la determinazione del concept alla base della ricerca condotta. E’ stata sviluppata e testata una metodologia multicriteriale e multilivello per la lettura del territorio rurale sviluppata in ambiente GIS, che si avvale di algoritmi di clustering (quale l’algoritmo IsoCluster) e classificazione a massima verosimiglianza, focalizzando l’attenzione sugli spazi agricoli periurbani. Tale metodo si incentra sulla descrizione del territorio attraverso la lettura di diverse componenti dello stesso, quali quelle agro-ambientali e socio-economiche, ed opera una sintesi avvalendosi di una chiave interpretativa messa a punto allo scopo, l’Impronta Agroambientale (Agro-environmental Footprint - AEF), che si propone di quantificare il potenziale impatto degli spazi rurali sul sistema urbano. In particolare obiettivo di tale strumento è l’identificazione nel territorio extra-urbano di ambiti omogenei per caratteristiche attraverso una lettura del territorio a differenti scale (da quella territoriale a quella aziendale) al fine di giungere ad una sua classificazione e quindi alla definizione delle aree classificabili come “agricole periurbane”. La tesi propone la presentazione dell’architettura complessiva della metodologia e la descrizione dei livelli di analisi che la compongono oltre che la successiva sperimentazione e validazione della stessa attraverso un caso studio rappresentativo posto nella Pianura Padana (Italia).

Geographic information system-based decision support for soil conservation planning in Tajikistan

Soil erosion on sloping agricultural land poses a serious problem for the environment, as well as for production. In areas with highly erodible soils, such as those in loess zones, application of soil and water conservation measures is crucial to sustain agricultural yields and to prevent or reduce land degradation. The present study, carried out in Faizabad, Tajikistan, was designed to evaluate the potential of local conservation measures on cropland using a spatial modelling approach to provide decision-making support for the planning of spatially explicit sustainable land use. A sampling design to support comparative analysis between well-conserved units and other field units was established in order to estimate factors that determine water erosion, according to the Revised Universal Soil Loss Equation (RUSLE). Such factor-based approaches allow ready application using a geographic information system (GIS) and facilitate straightforward scenario modelling in areas with limited data resources. The study showed first that assessment of erosion and conservation in an area with inhomogeneous vegetation cover requires the integration of plot-based cover. Plot-based vegetation cover can be effectively derived from high-resolution satellite imagery, providing a useful basis for plot-wise conservation planning. Furthermore, thorough field assessments showed that 25.7% of current total cropland is covered by conservation measures (terracing, agroforestry and perennial herbaceous fodder). Assessment of the effectiveness of these local measures, combined with the RUSLE calculations, revealed that current average soil loss could be reduced through low-cost measures such as contouring (by 11%), fodder plants (by 16%), and drainage ditches (by 53%). More expensive measures such as terracing and agroforestry can reduce erosion by as much as 63% (for agroforestry) and 93% (for agroforestry combined with terracing). Indeed, scenario runs for different levels of tolerable erosion rates showed that more cost-intensive and technologically advanced measures would lead to greater reduction of soil loss. However, given economic conditions in Tajikistan, it seems advisable to support the spread of low-cost and labourextensive measures.

Impacts of out-migration on land management in mountain areas

INTRODUCTION Out-migration from mountain areas is leaving behind half families and elderly to deal with managing the land alongside daily life challenges. A potential reduction of labour force as well as expertise on cropping practices, maintenance of terraces and irrigation canals, slope stabilization, grazing, forest and other land management practices are further challenged by changing climate conditions and increased environmental threats. An understanding of the resilience of managed land resources in order to enhance adaptation to environmental and socio-economic variability, and evidence of the impact of Sustainable Land Management (SLM) on the mitigation of environmental threats have so far not sufficiently been tackled. The study presented here aims to find out how land management in mountains is being affected by migration in the context of natural hazards and climate change in two study sites, namely Quillacollo District of Bolivia and Panchase area of Western Nepal, and which measures are needed to increase resilience of livelihoods and land management practices. The presentation includes draft results from first field work periods in both sites. A context of high vulnerability According to UNISDR, vulnerability is defined as “the characteristics and circumstances of a community, system or asset that make it susceptible to the damaging effects of a hazard”.Hazards are another threat affecting people’s livelihood in mountainous area. They can be either natural or human induced. Landslides, debris flow and flood are affecting peopleGood land management can significantly reduce occurrence of hazards. In the opposite bad land management or land abandonment can lead to negative consequences on the land, and thus again increase vulnerability of people’s livelihoods. METHODS The study integrates bio-physical and socio-economic data through a case study as well as a mapping approach. From the social sciences, well-tested participatory qualitative methodologies, typically used in Vulnerability and Capacity Analyses, such as semi-structured interviews with so-called ‘key informants’, transect walks, participatory risk and social resource mapping are applied. The bio-physical analysis of the current environmental conditions determining hazards and structural vulnerability are obtained from remote sensing analysis, field work studies, and GIS analysis The assessment of the consequences of migration in the area of origin is linked with a mapping and appraisal of land management practices (www.wocat.net, Schwilch et al., 2011). The WOCAT mapping tool (WOCAT/LADA/DESIRE 2008) allows capturing the major land management practices / technologies, their spread, effectiveness and impact within a selected area. Data drawn from a variety of sources are compiled and harmonised by a team of experts, consisting of land degradation and conservation specialists working in consultation with land users from various backgrounds. The specialists’ and land users’ knowledge is combined with existing datasets and documents (maps, GIS layers, high-resolution satellite images, etc.) in workshops that are designed to build consensus regarding the variables used to assess land degradation and SLM. This process is also referred to as participatory expert assessment or consensus mapping. The WOCAT mapping and SLM documentation methodologies are used together with participatory mapping and other socio-economic data collection (interviews, questionnaires, focus group discussions, expert consultation) to combine information about migration types and land management issues. GIS and other spatial visualization tools (e.g. Google maps) will help to represent and understand these links. FIRST RESULTS Nepal In Nepal, migration is a common strategy to improve the livelihoods. Migrants are mostly men and they migrate to other Asian countries, first to India and then to the Gulf countries. Only a few women are migrating abroad. Women migrate essentially to main Nepali cities when they can afford it. Remittances are used primarily for food and education; however they are hardly used for agricultural purposes. Besides traditional agriculture being maintained, only few new practices are emerging, such as vegetable farming or agroforestry. The land abandonment is a growing consequence of outmigration, resulting in the spreading of invasive species. However, most impacts of migration on land management are not yet clear. Moreover, education is a major concern for the respondents; they want their children having a better education and get better opportunities. Linked to this, unemployment is another major concern of the respondents, which in turn is “solved” through outmigration. Bolivia Migration is a common livelihood strategy in Bolivia. In the area of study, whole families are migrating downward to the cities of the valleys or to other departments of Bolivia, especially to Chapare (tropics) for the coca production and to Santa Cruz. Some young people are migrating abroad, mostly to Argentina. There are few remittances and if those are sent to the families in the mountain areas, then they are mainly used for agriculture purpose. The impacts of migration on land management practices are not clear although there are some important aspects to be underlined. The people who move downward are still using their land and coming back during part of the week to work on it. As a consequence of this multi-residency, there is a tendency to reduce land management work or to change the way the land is used. As in Nepal, education is a very important issue in this area. There is no secondary school, and only one community has a primary school. After the 6th grade students have therefore to go down into the valley towns to study. The lack of basic education is pushing more and more people to move down and to leave the mountains. CONCLUSIONS This study is on-going, more data have to be collected to clearly assess the impacts of out-migration on land management in mountain areas. The first results of the study allow us to present a few interesting findings. The two case studies are very different, however in both areas, young people are not staying anymore in the mountains and leave behind half families and elderly to manage the land. Additionally in both cases education is a major reason for moving out, even though the causes are not always the same. More specifically, in the case of Nepal, the use of remittances underlines the fact that investment in agriculture is not the first choice of a family. In the case of Bolivia, some interesting findings showed that people continue to work on their lands even if they move downward. The further steps of the study will help to explore these interesting issues in more detail. REFERENCES Schwilch G., Bestelmeyer B., Bunning S., Critchley W., Herrick J., Kellner K., Liniger H.P., Nachtergaele F., Ritsema C.J., Schuster B., Tabo R., van Lynden G., Winslow M. 2011. Experiences in Monitoring and Assessment of Sustainable Land Management. Land Degradation & Development 22 (2), 214-225. Doi 10.1002/ldr.1040 WOCAT/LADA/DESIRE 2008. A Questionnaire for Mapping Land Degradation and Sustainable Land Management. Liniger H.P., van Lynden G., Nachtergaele F., Schwilch G. (eds), Centre for Development and Environment, Institute of Geography, University of Berne, Berne

Detecting spatiotemporal clusters of accidental poisoning mortality among Texas counties, U.S., 1980 – 2001

Background Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial Scan Statistic in combination with GIS software was used to identify potential clusters between 1980 and 2001 among Texas counties, and Poisson regression was used to evaluate risk differences. Results Several significant (p < 0.05) accidental poisoning mortality clusters were identified in different regions of Texas. The geographic and temporal persistence of clusters was found to vary by racial group, gender, and race/gender combinations, and most of the clusters persisted into the present decade. Poisson regression revealed significant differences in risk according to race and gender. The Black population was found to be at greatest risk of accidental poisoning mortality relative to other race/ethnic groups (Relative Risk (RR) = 1.25, 95% Confidence Interval (CI) = 1.24 – 1.27), and the male population was found to be at elevated risk (RR = 2.47, 95% CI = 2.45 – 2.50) when the female population was used as a reference. Conclusion The findings of the present study provide evidence for the existence of accidental poisoning mortality clusters in Texas, demonstrate the persistence of these clusters into the present decade, and show the spatiotemporal variations in risk and clustering of accidental poisoning deaths by gender and race/ethnicity. By quantifying disparities in accidental poisoning mortality by place, time and person, this study demonstrates the utility of the spatial scan statistic combined with GIS and regression methods in identifying priority areas for public health planning and resource allocation.

Volume 16, Number 2: April/May 2010

Page 2 The Vice Provost for University Libraries reflects on Google’s recent experience in China. • A new digital collection of 19th-century Spanish women’s magazines is now available to researchers. Page 3 Collector Gary Wait donates a treasure trove of juvenile literature from the 19th century to the Northeast Children’s Literature Collection at the Thomas J. Dodd Research Center. Page 4 The Map and Geographic Information Center offers a new internship program, where students earn three academic credits and work eight hours a week while developing advanced Geographic Information Systems (GIS) and digitization skills. Page 5 Associate Professor of Anthropology Kevin McBride describes his work in having an important site in the Pequot War declared an historic battlefield. Page 6 Staff members celebrate anniversaries of library service. Page 7 The Libraries’ art exhibits program is celebrated in photos.

A systematized workflow for assessing land resources using readily available spatial datasets

Land degradation as well as land conservation maps at a (sub-) national scale are critical for pro-ject planning for sustainable land management. It has long been recognized that online accessible and low-cost raster data sets (e.g. Landsat imagery, SRTM-DEM’s) provide a readily available basis for land resource assessments for developing countries. However, choice of spatial, tempo-ral and spectral resolution of such data is often limited. Furthermore, while local expert knowl-edge on land degradation processes is abundant, difficulties are often encountered when linking existing knowledge with modern approaches including GIS and RS. The aim of this study was to develop an easily applicable, standardized workflow for preliminary spatial assessments of land degradation and conservation, which also allows the integration of existing expert knowledge. The core of the developed method consists of a workflow for rule-based land resource assess-ment. In a systematic way, this workflow leads from predefined land degradation and conserva-tion classes to field indicators, to suitable spatial proxy data, and finally to a set of rules for clas-sification of spatial datasets. Pre-conditions are used to narrow the area of interest. Decision tree models are used for integrating the different rules. It can be concluded that the workflow presented assists experts from different disciplines in col-laboration GIS/RS specialists in establishing a preliminary model for assessing land degradation and conservation in a spatially explicit manner. The workflow provides support when linking field indicators and spatial datasets, and when determining field indicators for groundtruthing.

La planificación ambiental estratégica en los instrumentos de ordenamiento territorial. Caso de estudio: el Plan Regulador Intercomunal del Alto Aconcagua (PRIAA), provincias de San Felipe y Los Andes, V Región, Valparaíso, Chile

El artículo presenta la aplicación de un modelo de Planificación Ambiental Estratégica al diseño de un Plan de Ordenamiento Territorial en la zona de estudio, cuyo territorio se caracteriza por poseer un significativo patrimonio ambiental en términos de recursos naturales, paisaje, historia, etc. Junto a lo anterior, muestra un fuerte dinamismo económico por su localización en relación a la Macrozona Central de Chile, el Mercosur y el futuro corredor bioceánico. El objetivo fue diseñar una metodología que permitiera incorporar la dimensión ambiental en cada en cada una de las etapas características de elaboración de un Plan Regulador. El estudio ambiental se baso en tres etapas: diagnóstico ambiental, evaluación ambiental de alternativas y definición del proyecto, para lo cual se desarrollaron metodologías especificas apoyadas en sistemas de información geográfica (SIG) y modelos de simulación. La aplicación del modelo de planificación ambiental estratégica permitió obtener un Plan territorial con zonas y ordenanzas que protejan el patrimonio ambiental existente y aminore los impactos ambientales negativos de futuras actividades que se instalen en un territorio.

La Evaluación de impacto ambiental y el ordenamiento territorial

En general las metodologías utilizadas para la evaluación de impacto ambiental han empleado ponderaciones subjetivas, o mediciones de ciertos componentes en forma parcializada, en donde no se tiene en cuenta el territorio sobre el cual se desarrollan las acciones y los efectos. Esto hace que las EIA no sean ajustadas, tornándose más dificultoso aún en las evaluaciones relacionadas con temas de Ordenamiento Territorial, donde la complejidad está dada no solo por la cantidad de variables a incluir sino por el nivel de interacciones a considerar. A pesar de que no siempre es tenida en cuenta, la componente espacial es fundamental en toda EIA, no solo para describir el entorno en el que las acciones se realizan sino para el análisis y correlación de fenómenos que impactan en el territorio y el medio ambiente. En este trabajo se persigue: • Identificar indicadores geográficos posibles de incorporar en las EIA. • Medir en forma cuali y cuantitativa los indicadores seleccionados . • Utilizar geotecnologías como son los SIG y la Teledetección en dicha medición. La incorporación de indicadores geográficos en la EIA de temas tan complejos y comprometidos como los relacionados con el Ordenamiento Territorial se torna necesario debido a la propia naturaleza de ciertos fenómenos que requieren de un enfoque integral georeferenciado, con indicadores medidos en forma cualitativa o cuantitativa.

Evaluación geoecológica de los paisajes del Departamento Minas (Provincia de Neuquén), para el estudio de la degradación de la tierra

Las sociedades en su afán de aprovechar los recursos naturales que la tierra le provee, han ido transformando permanentemente el medio que habitamos, generando una crisis ambiental que es tema de preocupación y permanente discusión en organismos, foros y conferencias relacionados con el cuidado y protección del medio ambiente. En las regiones áridas y semiáridas uno de los problemas ambientales más comunes es la degradación de tierras por efecto del sobrepastoreo. La tercera parte de la superficie terrestre del planeta es árida y semiárida y en ella los procesos de desertización se han intensificado en los últimos decenios. Según la Convención de las Naciones Unidas de lucha contra la Desertificación (CNULD), este problema amenaza al 40 por ciento aproximadamente, de la masa terrestre de nuestro planeta. Más de 1000 millones de personas en alrededor de 100 países están afectadas directamente por la desertificación o corren peligro de estarlo (CNULD, 2003), estimándose que "la pérdida de ingresos en las áreas afectadas alcanza a unos 42.000 millones de dólares". Argentina en general y la Patagonia en particular, no son ajenas a esta situación. La Secretaría de Recursos Naturales y Medio Ambiente Humano (1996), calcula que aproximadamente el 75 por ciento de nuestro territorio nacional se encuentra afectado por crecientes condiciones de aridez y en la Patagonia, el 90 por ciento de la superficie (unos 780.000 km2) presenta signos de degradación. De esta superficie, un 30 por ciento, está bajo procesos erosivos eólicos e hídricos severos o graves con tendencia a agravarse. Teniendo en cuenta esta situación, esta tesis tiene como propósito aplicar las concepciones metodológicas de la geoecología de los paisajes en el Departamento Minas (Provincia de Neuquén), con vistas a estudiar la estructura y funcionamiento de los paisajes, herramienta fundamental para comprender el fenómeno de la degradación de la tierra. El objetivo central de este trabajo consiste en estudiar la degradación de los paisajes de este lugar a partir de los preceptos de la geoecología, con apoyo de los Sistemas de Información Geográfica y la teledetección, estableciendo índices diagnósticos que reflejen la interacción e interdependencia entre los componentes naturales y sociales del paisaje. El estudio de los paisajes brinda la posibilidad de integrar transdisciplinariamente los conocimientos y percepciones de la diversidad geoecológica y socioeconómica desde una perspectiva dinámica. Mediante este análisis se puede arribar al conocimiento de las formas de ocupación y conservación de los recursos naturales procurando la protección de la oferta ecológica a largo plazo. El paisaje geográfico o geosistema se concibe como "un sistema espacio-temporal, complejo y abierto, que se origina y evoluciona justamente en la interfase naturaleza-sociedad, en un constante estado de intercambio de energía, materia e información, donde su estructura, funcionamiento, dinámica y evolución reflejan la interacción entre los componentes naturales (abióticos y bióticos), técnico-económicos y socio-culturales (Mateo, J. 1991; Salinas. E. 1991y 1997). Se trata de una formación socio-natural que constituye una categoría científica y como tal, será adoptada en este trabajo.

Evaluación geoecológica de los paisajes del Departamento Minas (Provincia de Neuquén), para el estudio de la degradación de la tierra

Las sociedades en su afán de aprovechar los recursos naturales que la tierra le provee, han ido transformando permanentemente el medio que habitamos, generando una crisis ambiental que es tema de preocupación y permanente discusión en organismos, foros y conferencias relacionados con el cuidado y protección del medio ambiente. En las regiones áridas y semiáridas uno de los problemas ambientales más comunes es la degradación de tierras por efecto del sobrepastoreo. La tercera parte de la superficie terrestre del planeta es árida y semiárida y en ella los procesos de desertización se han intensificado en los últimos decenios. Según la Convención de las Naciones Unidas de lucha contra la Desertificación (CNULD), este problema amenaza al 40 por ciento aproximadamente, de la masa terrestre de nuestro planeta. Más de 1000 millones de personas en alrededor de 100 países están afectadas directamente por la desertificación o corren peligro de estarlo (CNULD, 2003), estimándose que "la pérdida de ingresos en las áreas afectadas alcanza a unos 42.000 millones de dólares". Argentina en general y la Patagonia en particular, no son ajenas a esta situación. La Secretaría de Recursos Naturales y Medio Ambiente Humano (1996), calcula que aproximadamente el 75 por ciento de nuestro territorio nacional se encuentra afectado por crecientes condiciones de aridez y en la Patagonia, el 90 por ciento de la superficie (unos 780.000 km2) presenta signos de degradación. De esta superficie, un 30 por ciento, está bajo procesos erosivos eólicos e hídricos severos o graves con tendencia a agravarse. Teniendo en cuenta esta situación, esta tesis tiene como propósito aplicar las concepciones metodológicas de la geoecología de los paisajes en el Departamento Minas (Provincia de Neuquén), con vistas a estudiar la estructura y funcionamiento de los paisajes, herramienta fundamental para comprender el fenómeno de la degradación de la tierra. El objetivo central de este trabajo consiste en estudiar la degradación de los paisajes de este lugar a partir de los preceptos de la geoecología, con apoyo de los Sistemas de Información Geográfica y la teledetección, estableciendo índices diagnósticos que reflejen la interacción e interdependencia entre los componentes naturales y sociales del paisaje. El estudio de los paisajes brinda la posibilidad de integrar transdisciplinariamente los conocimientos y percepciones de la diversidad geoecológica y socioeconómica desde una perspectiva dinámica. Mediante este análisis se puede arribar al conocimiento de las formas de ocupación y conservación de los recursos naturales procurando la protección de la oferta ecológica a largo plazo. El paisaje geográfico o geosistema se concibe como "un sistema espacio-temporal, complejo y abierto, que se origina y evoluciona justamente en la interfase naturaleza-sociedad, en un constante estado de intercambio de energía, materia e información, donde su estructura, funcionamiento, dinámica y evolución reflejan la interacción entre los componentes naturales (abióticos y bióticos), técnico-económicos y socio-culturales (Mateo, J. 1991; Salinas. E. 1991y 1997). Se trata de una formación socio-natural que constituye una categoría científica y como tal, será adoptada en este trabajo.