Combining classification techniques to define topo-climatic landscapes

Landscape classification tackles issues related to the representation and analysis of continuous and variable ecological data. In this study, a methodology is created in order to define topo-climatic landscapes (TCL) in the north-west of Catalonia (north-east of the Iberian Peninsula). TCLs relate the ecological behaviour of a landscape in terms of topography, physiognomy and climate, which compound the main drivers of an ecosystem. Selected variables are derived from different sources such as remote sensing and climatic atlas. The proposed methodology combines unsupervised interative cluster classification with a supervised fuzzy classification. As a result, 28 TCLs have been found for the study area which may be differentiated in terms of vegetation physiognomy and vegetation altitudinal range type. Furthermore a hierarchy among TCLs is set, enabling the merging of clusters and allowing for changes of scale. Through the topo-climatic landscape map, managers may identify patches with similar environmental conditions and asses at the same time the uncertainty involved.

An approach to costs and energy consumption in private urban Spanish Mediterranean landscapes from a simplified model in sprinkle irrigation

The number of private gardens has increased in recent years, creating a more pleasant urban model, but not without having an environmental impact, including increased energy consumption, which is the focus of this study. The estimation of costs and energy consumption for the generic typology of private urban gardens is based on two simplifying assumptions: square geometry with surface areas from 25 to 500 m2 and hydraulic design with a single pipe. In total, eight sprinkler models have been considered, along with their possible working pressures, and 31 pumping units grouped into 5 series that adequately cover the range of required flow rates and pressures, resultin in 495 hydraulic designs repeated for two climatically different locations in the Spanish Mediterranean area (Girona and Elche). Mean total irrigation costs for the locality with lower water needs (Girona) and greater needs (Elche) were € 2,974 ha-¹ yr-¹ and € 3,383 ha-¹ yr-¹, respectively. Energy costs accounted for 11.4% of the total cost for the first location, and 23.0% for the second. While a suitable choice of the hydraulic elements of the setup is essential, as it may provide average energy savings of 77%, due to the low energy cost in relation to the cost of installation, the potential energy savings do not constitute a significant incentive for the irrigation system design. The low efficiency of the pumping units used in this type of garden is the biggest obstacle and constraint to achieving a high quality energy solution

Monitoring spatial and temporal dynamics of bird communities in Mediterranean landscapes affected by largewildfires = Seguimiento de la dinámica espacial y temporal de comunidades de aves en paisajes mediterráneos afectados por grandes fuegos

We presented a bird-monitoring database inMediterranean landscapes (Catalonia, NE Spain) affected by wildfires and we evaluated: 1) the spatial and temporal variability in the bird community composition and 2) the influence of pre-fire habitat configuration in the composition of bird communities. The DINDIS database results fromthemonitoring of bird communities occupying all areas affected by large wildfires in Catalonia since 2000.We used bird surveys conducted from 2006 to 2009 and performed a principal components analysis to describe two main gradients of variation in the composition of bird communities, which were used as descriptors of bird communities in subsequent analyses. We then analysed the relationships of these community descriptors with bioclimatic regions within Catalonia, time since fire and pre-fire vegetation (forest or shrubland).We have conducted 1,918 bird surveys in 567 transects distributed in 56 burnt areas. Eight out of the twenty most common detected species have an unfavourable conservation status, most of them being associated to open-habitats. Both bird communities’ descriptors had a strong regional component and were related to pre-fire vegetation, and to a lesser extent to the time since fire.We came to the conclusion that the responses of bird communities to wildfires are heterogeneous, complex and context dependent. Large-scale monitoring datasets, such as DINDIS, might allow identifying factors acting at different spatial and temporal scales that affect the dynamics of species and communities, giving additional information on the causes under general trends observed using other monitoring systems

Landscape context on generalist and specialist aphid natural enemies

Report for the scientific sojourn at the University of Lund, Sweden, between May and September 2007. A landscape-scale research approach has been highlighted by a growing body of literature as essential for understanding important ecosystem services as biological control. Aphids are victims of a diversity of enemies making the aphid-enemy interaction a nice example for the role of enemy diversity for the functioning of biological control. Here it is examined the effects of landscape complexity on cereal aphids and associated natural enemies that varied in the degree of specialization. Parasitoids wasps abundance did not differ between landscape types but was strongly negatively related to the percentage of arable land. In contrast, abundances of generalist predators like Coccinellidae were significantly higher in simple landscapes since can benefit from the high availability of a variety of alternative resources within cropping systems. Consequently coccinellidae-to-aphid ratio was significantly higher in fields in homogenous landscapes as compared to fields included in an heterogeneous landscape, suggesting that enemy pressure on cereal aphids increases with landscape simplification. The landscape effect will depend mainly on the degree of specialization of functionally dominant natural enemies, so that the results imply that conservation actions aiming to optimise abundance for one taxonomic group in the agricultural landscape will not automatically increase abundance of other groups. Given that the strength of natural enemy impact on biocontrol depends on landscape features and the role of functionally dominant natural enemies. So, therefore it is essential to focus the future empirical work in examining the schedule of agricultural landscapes that maintain a diversity of generalist and specialist natural enemies.

Classificació i importància dels elements paisatgístics del territori Tsimane' segons la percepció local

En aquesta tesis es presenten els resultats de la investigació duta a terme a les comunitats indígenes Tsimane’ de l’Amazònia boliviana. La investigació estudia la percepció dels indígenes sobre l’etnoclassificació del seu territori. S’estableix una clau de classificació i es determina la importància dels elements paisatgístics del territori Tsimane’ segons la percepció local. Aquesta informació permetrà integrar el coneixement local dins dels programes de desenvolupament integral i de planificació territorial en l’Amazònia Boliviana. L’estudi conclou que la població Tsimane’ classifica els elements paisatgístics del seu entorn en 89 taques conformades per una espècies arbòria dominant i que estan incloses en un o més dels nou paisatges identificats: Därsi Därä, Sajras, Sinues Ojñi’, Mayes, Múcúya, Tsäquis Därä, Cum, Tajñi’ i Jaman. A partir d’un anàlisi multicriteri s’ha determinat una importància total per cada paisatge segons els següents criteris d’importància: diversitat de taques, activitats econòmiques realitzables, presència espiritual, percepció individual i importància relativa segons els altres paisatges. Així doncs s’ha trobat que el paisatge més important és el Därsi Därä (bosc primari caracteritzat per un estrat arbori superior a 50 metres d’altura). També s’han analitzat les dades discernint segons el gènere de l’entrevistat i segons la proximitat de les comunitats estudiades a la ciutat més propera.

Linkages of dietary patterns, international trade and land use: the case of olive oil in the European Union

Within only two decades olive oil developed from a niche product which could hardly be found in food stores outside the producing regions towards an integrated component in the diets of industrial countries. This paper discusses the impacts of the promotion of the “healthy Mediterranean diet” on land use and agro-ecosystems in the producing countries. It examines the dynamics of olive oil production, trade and consumption in the EU15 in the period 1972 to 2003 and the links between dietary patterns, trade and land use. It analyses the underlying socio-economic driving forces behind the increasing spatial disconnect between production and consumption of olive oil in the EU15 and in particular in Spain, the world largest producer during the last three decades. In the observed period olive oil consumption increased 16 fold in the non-producing EU15 countries. In the geographically limited producing regions like Spain, the 5 fold increase in export production was associated with the rapid industrialization of olive production, the conversion of vast Mediterranean landscapes to olive monocultures and a range of environmental pressures. High amounts of subsidies of the European Common Agricultural Policy and feedback loops within production and consumption systems were driving the transformation of the olive oil system. Our analysis indicates the process of change was not immediately driven by increases in demand for olive oil in non-producing countries, but rather by the institutional setting of the European Union and by concerted political interventions.

Textural classification of land cover using support vector machines: an empirical comparison with parametric, non parametric and hybrid classifiers in the Bolivian Amazon

Land cover classification is a key research field in remote sensing and land change science as thematic maps derived from remotely sensed data have become the basis for analyzing many socio-ecological issues. However, land cover classification remains a difficult task and it is especially challenging in heterogeneous tropical landscapes where nonetheless such maps are of great importance. The present study aims to establish an efficient classification approach to accurately map all broad land cover classes in a large, heterogeneous tropical area of Bolivia, as a basis for further studies (e.g., land cover-land use change). Specifically, we compare the performance of parametric (maximum likelihood), non-parametric (k-nearest neighbour and four different support vector machines - SVM), and hybrid classifiers, using both hard and soft (fuzzy) accuracy assessments. In addition, we test whether the inclusion of a textural index (homogeneity) in the classifications improves their performance. We classified Landsat imagery for two dates corresponding to dry and wet seasons and found that non-parametric, and particularly SVM classifiers, outperformed both parametric and hybrid classifiers. We also found that the use of the homogeneity index along with reflectance bands significantly increased the overall accuracy of all the classifications, but particularly of SVM algorithms. We observed that improvements in producer’s and user’s accuracies through the inclusion of the homogeneity index were different depending on land cover classes. Earlygrowth/degraded forests, pastures, grasslands and savanna were the classes most improved, especially with the SVM radial basis function and SVM sigmoid classifiers, though with both classifiers all land cover classes were mapped with producer’s and user’s accuracies of around 90%. Our approach seems very well suited to accurately map land cover in tropical regions, thus having the potential to contribute to conservation initiatives, climate change mitigation schemes such as REDD+, and rural development policies.

Natura i història en la creació dels "paisatges de l'aigua" a la plana de l'Alt Empordà

L’objectiu d’aquest article és fer una aproximació al procés històric de creació dels anomenats “paisatges de l’aigua” a la plana de l’Alt Empordà. En primer lloc, es presenten els principals elements que configuren els paisatges de l’aigua a la plana (els rius, les rieres, els aiguamolls, els estanys, les sèquies, canals de regadiu, etc.). A continuació, s’analitza el procés històric de creació dels paisatges de l’aigua a la plana de l’Alt Empordà a través d’un discurs que s’ha simplificat en dues grans etapes: una llarga etapa caracteritzada per la lluita mantinguda per la societat altempordanesa contra l’aigua i, una segona etapa, molt més recent, on els esforços d’aquesta societat es concentren en l’obtenció d’aquesta aigua. Per últim, s’analitza en detall aquest procés a partir del cas concret del paisatge configurat per les closes

Identificació de paisatges funcionals mitjançant anàlisi cluster

El terme paisatge i les seves aplicacions són cada dia més utilitzats per les administracions i altres entitats com a eina de gestió del territori. Aprofitant la gran quantitat de dades en bases compatibles amb SIG (Sistemes d’Informació Geogràfica) existents a Catalunya s’ha desenvolupat una síntesi cartogràfica on s’identifiquen els Paisatges Funcionals (PF) de Catalunya, concepte que fa referència al comportament fisico-ecològic del terreny a partir de variables topogràfiques i climàtiques convenientment transformades i agregades. S’ha utilitzat un mètode semiautomàtic i iteratiu de classificació no supervisada (clustering) que permet la creació d’una llegenda jeràrquica o nivells de generalització. S’ha obtingut com a resultat el Mapa de Paisatges Funcionals de Catalunya (MPFC) amb una llegenda de 26 categories de paisatges i 5 nivells de generalització amb una resolució espacial de 180 m. Paral·lelament, s’han realitzat validacions indirectes sobre el mapa obtingut a partir dels coneixements naturalistes i la cartografia existent, així com també d’un mapa d’incertesa (aplicant lògica difusa) que aporten informació de la fiabilitat de la classificació realitzada. Els Paisatges Funcionals obtinguts permeten relacionar zones de condicions topo-climàtiques homogènies i dividir el territori en zones caracteritzades ambientalment i no políticament amb la intenció que sigui d’utilitat a l’hora de millorar la gestió dels recursos naturals i la planificació d’actuacions humanes.

Al di là del fiume - attraverso il fiume: il basso corso del Ter in Catalogna

La ricerca prende in considerazione dal punto di vista dell’architettura e dell’urbanistica la relazione tra la città e il fiume che la attraversa o la lambisce; l’insediamento umano viene analizzato nel contesto del bacino idrografico al quale appartiene. La ricerca è stata sviluppata in seno alla tesi dottorale ora in fase di elaborazione presso il Departamento de Urbanismo y Ordenación del Territorio dell’Universidad Politecnica de Catalunya. La tesi ha come caso studio il tratto basso del fiume Ter in Catalogna. Nella discussione sul paesaggio urbano contemporaneo oggi la riflessione è centrata sulla città che si territorializza; la dimensione urbana interferisce con gran parte della superficie della terra facendo sfumare le tradizionali distinzioni tra urbano e non-urbano, tra spazio costruito e spazio aperto. In questo contesto, quale termine di conciliazione tra la dinamica naturale e la costruzione storica dei luoghi prodotta dall’intervento umano, il fiume si rivela uno strumento essenziale di analisi e progetto. L’obiettivo di questa ricerca è suggerire un’approssimazione al progetto della città che si sviluppa lungo il corso fluviale costruendo strumenti per la riflessione “attraverso il fiume”. Partendo dall’ipotesi che la città si insedia lungo un corso d’acqua secondo una sintassi territoriale stabilita dalla geografía e dalla geomorfologia del fiume stesso, il fine è fornire strumenti per il processo di recupero degli spazi fluviali in contesti urbanizzati. Il fiume diviene componente geografica chiave degli insediamenti dispersi e risorsa per costruirne l’abitabilità.

Relació entre el percentatge i número absolut de cèl·lules Natural Killer i de l’expressió dels seus receptors NKG2D i NKp46 i les diferents formes de presentació de la Tuberculosi. Resultats preliminars.

La tuberculosi pot localitzar-se al pulmó: TB-P o altres òrgans: TB-EP, segons el compromís del sistema immunitari de l’hoste, on hi intervenen les cèl.lules Natural Killer-NK. L’estudi analitza el percentatge i número absolut d’NK i l’expressió dels receptors d’activació, NKG2D - NKp46, en 15 malalts/TB-P, 15 malalts/TB-EP i 15 sans, trobant-se augmentades en percentatge en el grup TB-P, disminuïdes en número absolut en els TB-EP i TB-P, i valors més alts d’ NKG2D, sobretot, malalts de TB-EP. Les coincidències amb d’altres estudis i les troballes preliminars obren possibilitats a investigacions en el camp de la TB-EP i la reacció immune.

De viles rurals a indrets de la regió metropolitana de Barcelona: transformacions històriques del paisatge a la Vall del Congost (Figaró-Montmany, l’Ametlla del Vallès i la Garriga, 1850-2010)

El projecte ha assolit la majoria d’objectius, ajustats a la reducció d'una quarta part de l'import concedit: 1) caracteritzar la transformació del paisatge agro-forestal i urbà a dos municipis de la vall del Congost, La Garriga i Figaró-Montmany, reconstruint amb SIG els mapes d'ús del sòl de 1854, 1949, 1956 i 2005, obtenint per intersecció de cobertes les matrius dels canvis d'ús; i 2) avaluar amb l’índex de connectivitat ecològica l'impacte ambiental d'aquells canvis des del punt de vista de la biodiversitat i la resiliència del paisatges, amb un especial èmfasi en la reforestació induïda per l'abandonament rural i la pèrdua de paisatges en mosaic, en un àmbit més gran pel període 1956-1993-2005. Aquests resultats han permès preparar varis articles per publicar en co-autoría a revistes com Landscape History, Environment and History o Landscape and Urban Planning. Ja és a punt de poder-se lliurar el primer amb el títol de "Looking backwards into a Mediterranean edge environment: Landscape changes and ecological connectivity in El Congost Valley (province of Barcelona, Catalonia) 1850-2005", incloent dos objectius esmentats a la memòria: identificar les principals forces motores d'aquells canvis en el paisatge relacionant els usos del sòl amb les formes d'ordenació del territori, caracteritzar-ne les forces rectores econòmico-socials i el paper jugat per la protecció del Parc Natural del Montseny i els Cingles de Bertí. Els resultats també permetran abordar en el futur altres aspectes, com per exemple estimar el potencial energètic de la biomassa local tot cercant que el seu aprofitament generi sinèrgies territorials positives per a l'ecologia del paisatge amb la recuperació d’una ramaderia extensiva i una agricultura ecològica que facin possible la restauració dels paisatges en mosaic. L'estudi ha pogut incorporar un aspecte inicialment no previst, el cens d'orquídies mediterrànies a Figaró-Montmany elaborat pel naturalista Paul Wilcox

Automatic low baseline stereo in urban areas

In this work we propose a new automatic methodology for computing accurate digital elevation models (DEMs) in urban environments from low baseline stereo pairs that shall be available in the future from a new kind of earth observation satellite. This setting makes both views of the scene similarly, thus avoiding occlusions and illumination changes, which are the main disadvantages of the commonly accepted large-baseline configuration. There still remain two crucial technological challenges: (i) precisely estimating DEMs with strong discontinuities and (ii) providing a statistically proven result, automatically. The first one is solved here by a piecewise affine representation that is well adapted to man-made landscapes, whereas the application of computational Gestalt theory introduces reliability and automation. In fact this theory allows us to reduce the number of parameters to be adjusted, and tocontrol the number of false detections. This leads to the selection of a suitable segmentation into affine regions (whenever possible) by a novel and completely automatic perceptual grouping method. It also allows us to discriminate e.g. vegetation-dominated regions, where such an affine model does not apply anda more classical correlation technique should be preferred. In addition we propose here an extension of the classical ”quantized” Gestalt theory to continuous measurements, thus combining its reliability with the precision of variational robust estimation and fine interpolation methods that are necessary in the low baseline case. Such an extension is very general and will be useful for many other applications as well.

La bella molinera

Aquest treball vol ser una aproximació a l’obra Die schöne Müllerin, D795, un cicle de vint cançons per a veu i piano, que Franz Schubert va compondre l’any 1823. L’obra es basa en un conjunt de poemes que havia escrit poc abans Wilhelm Müller, i que expliquen la història del desengany amorós d’un jove aprenent de moliner. La bella molinera presenta un ventall infinit de colors, emocions, paisatges... Va des de l’alegria més eufòrica fins a la desesperança més fonda, passant per moments d’ironia, de somnis i de sorpreses. Tot això és analitzat en el treball, número per número, tan en l’aspecte literari com en el musical, i en la seva interrelació.

Is lumpy investment really irrelevant for the business cycle?

New-Keynesian (NK) models can only account for the dynamic effects of monetary policy shocks if it is assumed that aggregate capital accumulation is much smoother than it would be the case under frictionless firm-level investment, as discussed in Woodford (2003, Ch. 5). We find that lumpy investment, when combined with price stickiness and market power of firms,can rationalize this assumption. Our main result is in stark contrast with the conclusions obtained by Thomas (2002) in the context of a real business cycle (RBC) model. We use our model to explain the economic mechanism behind this difference in the predictions of RBC and NK theory.