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This research addresses the geomorphological connectivity existing amid the piedmont’s karstic fillings (Sierra de Esparteros) and the Guadaíra and Guadalquivir Rivers’ alluvial terraces (SW of Spain), spotted with vestiges of human activities (Middle Palaeolithic). This study includes the analysis of 20 geoarchaeological sites and 28 lithic assemblages, with a total of 13,233 lithic pieces. Techno-typological and use–wear (SEM) analyses were conducted on these artifacts. Depending on the raw materials and the provenance of these lithic industries, two groups of assemblages were identified: one made of quartzite from the north, and another made of flint from the south. Two main geochronological periods were established (OSL and U/Th): (1) a short duration (MIS6/MIS5) and (2) a long duration (MIS5/MIS3). Techno-typological analysis showed three sorts of activities: (a) the provision and distribution of raw materials, (b) knapping, and (c) other activities that imply the use of a lithic workshop (LW), along with the settlement characteristics of habitual or recurrent (HS), temporary (TS), and indeterminate (IN). This geoarchaeological connectivity is called the “hominid alluvial corridor” (HAC). The underlined features are the geomorphological units, the continuum alluvial series, the raw material of the lithic industries as an indicator of provenance and transportation throughout the alluvial system, and the use–wear analysis of the tool-kit to interpret the functionality of the pieces.

The state of Paraíba in northeast Brazil contains four of the seven biomes present in the country: Mata Atlântica, Cerrado, Caatinga and Matas Serranas. On the other hand, Amazônia, Pantanal and Pampa were not found in this area. This special situation allows us to analyse changes in the distribution of these four large Brazilian biomes according to bioclimatic conditions, using the methodology of bioclimatic regime types. Based on the analysis of variables from periods of hydric and thermal vegetation stagnation, obtained from hydric and bioclimatic balances, average monthly temperature and rainfall, that methodology enables us to establish a typology of 27 types of bioclimatic regimes and 243 bioclimatic regime subtypes with the 9 Thornthwaite ombrothermal levels. In Paraíba 4 types of bioclimatic regimes are currently identified (mesophyllo, tropophyllo, xerophyllo and eurythermophilous) and 9 subtypes according to ombrothermal levels. In order to analyse the changes, extreme change situations were chosen: a past scenario with the Last Glacial Maximum (40 ky); and an RCP 8.5 climate change scenario for the CMSS 4.0 model for the year 2070. This enabled 3 bioclimatic regime maps of each of the 3 aforementioned situations to be obtained, providing a map of potential distribution of the plant formations of Paraíba state according to the specific field knowledge and bioclimatic mapping obtained for the present. This paper concludes that a retrocession of the Mata Atlântica can be seen from the Last Glacial Maximum up to the present, losing its optimal bioclimatic conditions and therefore remaining in a highly fragile relict situation in the face of anthropic pressure (sugarcane cultivation and urban expansion); an advance toward 2070 of the Caatinga in its shrub form as a predominant formation is indicated by the projection of climate change in 2070 for the analysed situation, specifically resulting from anthropic pressure, in this case due to livestock activities which have affected this biome in Paraíba since the mid-19th century.

The objective of this study is to identify and analyse the main characteristics of areas potentially degraded by desertification and of preserved areas using the Soil Surface Moisture Index (SSMI), alongside the Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI). The study is based on a set of points obtained in the field and from the RGB false colour image for the Environmental Protection Areas (EPA) of the Cariri, in the semi-arid region of Paraíba, using a space-time cross-section covering both rainy and dry periods. The results showed that at all points in Desertified Areas, the main characteristics were a low SSMI, high LST and low NDVI in both periods. The Preserved Areas, on the other hand, presented a high SSMI, moderate LST and high NDVI in the rainy period, with the same characteristics repeated in the dry period for SSMI and NDVI, but with a low LST. Timely identification of these characteristics, both in areas degraded by desertification and in better preserved areas, can provide useful information for future decisions relating to the physical and territorial management of the Conservation Unit.

Los bosques poseen un rol clave en la mitigación del cambio climático ya que contribuyen a reducir los gases del efecto invernadero. Este trabajo tiene como objetivo conocer la diversidad, la biomasa y la captura de carbono de un bosque secundario de caldén (Prosopis caldenia) de la Argentina. Su importancia radica en ser una formación vegetal nativa y endémica que ha sido modificado a través de la historia por la valoración de sus recursos naturales. Para cumplir con el objetivo, se aplicó la metodología de REDD+ que consta de un inventario aleatorio de 10 parcelas circulares cuya superficie total es de 1 ha. Se seleccionó como área de estudio la Reserva Provincial Laguna Guatraché, provincia de La Pampa. Los resultados determinaron que el bosque de caldén contiene 156,4 Mg/ha de biomasa y la captura de carbono que realiza es de 78,2 t/ha. Conocer este valor contribuye a comprender los servicios ecosistémicos de este bosque y la importancia de su conservación.

The PDZ domains are modular domains that recognise short linear C-terminal sequences in proteins that organise the formation of complex multi-component assemblies. We have crystallised the third PDZ domain of the neuronal postsynaptic density-95 protein (PSD95-PDZ3) at mildly acidic pH conditions and obtained up to four polymorphs. Thus, below pH 4.0, the protein crystallised into prism-shaped crystals that belonged to the trigonal space group P3112. In contrast, above this pH value, the crystals’ shape changes to long needles belonging to the monoclinic P21 and two different orthorhombic packings of the P212121 space group. In addition, all the polymorphs share the main crystallographic interface, where the sidechain of the Asp332 imitates the binding of the C-terminal moiety to the canonical binding motif. Furthermore, we have analysed how changes in the ionisation state of some specific residues might be critical for crystallising the different polymorphs. The analysis of these polymorphs provides clues on the relevance of specific protein-protein interactions in protein crystallisation. However, these structures allow dissecting those electrostatic interactions that play a role in the conformation adopted by some residues and the extra-domain components upon binding C-terminal sequences.

The river Guadaira in its lower course has undergone various transformations, from historical interventions for the installation of water mills, to those made in the riverbed since the beginning of the 20th century to mitigate floods in the city of Seville. A critical analysis and assessment is made of proposed ‘Guadaira Greenbelt’ for the recovery of the marginal peri-urban space linked to the most recent transformation of the river in 1977. The ecological and social scope of this proposal is analysed and evaluated in a SWOT analysis, with a clearly socio-environmental objective that seeks the sustainability of the area, which is discussed in comparison other national and international experiences. The conclusions highlight the errors related to the Mediterranean riparian plant formations, which is one of the most important weaknesses of the proposal. The research concludes that the proposal meets the objectives of the ENRR, but does not adapt to the academic patterns on research on river and river restoration.

An analytical and cartographic method of biomass distribution and plant formations at a multi-scalar level is developed based on bioclimatic variables extracted from the Thornthwaite Water Balance (WB) and the Bioclimatic Balances (BB) of Montero de Burgos & González Rebollar. As a result, a distribution map involving Types of Bioclimatic Regimens (TBR) is obtained leading to the identification of a multi-scale classification at different levels: zonal (macro-scale) with 5 types, regional (meso-scale) with 27 types, and local (micro-scale) with 162 plant formations subtypes, conditioned by lithology-soils, the relief exposure to wind or sunstroke respectively and obtained through the combination of TBR and ombroclimates.

La Biogeografía está en el origen de la Geografía moderna. Desde el principio, el estudio de la distribución de los seres vivos y la interpretación de los nichos ecológicos ha constituido uno de los frentes más activos de la Geografía Física. Sin embargo, en algunos países, los geógrafos abandonaron el enfoque ecológico en los estudios de biogeográficos. En este artículo, se propone un flujo de trabajo general para integrar la modelización de nichos ecológicos en el contexto de la Biogeografía como ciencia geográfica que estudia patrones de biodiversidad. El estudio de caso aborda la predicción del nicho ecológico fundamental del alcornoque en Andalucía.

Los ecosistemas con flujos de servicios ambientales óptimos ofrecen una adecuada calidad en sus hábitats que coadyuvan a mantener su biodiversidad. Esta calidad puede reducirse por los factores de mayor intensidad y cercanía al hábitat, lo que puede estudiarse con herramientas geoespaciales. Este trabajo evaluó los niveles de degradación relativa de hábitat en la cuenca Guayalejo-Tamesí (Tamaulipas, México), respecto a los factores adyacentes que amenazan su calidad, usando el modelador Habitat Quality del Toolbox InVest 1.005beta para ArcGis-9.2. Los ecosistemas con menor amenaza a su hábitat (degradación nula o menor a 20 %) y con mejores oportunidades de conservación, representan el 77,3 % de la superficie de la cuenca. Particularmente, los hábitats montañosos (bosques templados y mesófilo) son los mejor conservados, pues más del 80 % de su superficie se encuentra libre de degradación; destaca el bosque mesófilo de montaña, con un 94 % de su superficie no degradada, debido a su escasa exposición a factores amenazantes. Se concluye que, a pesar del uso intensivo del territorio de la cuenca, existen ecosistemas bien conservados, especialmente en zonas aisladas; la mayoría de ellas carecen de protección legal, por lo que se encuentran expuestas a la ampliación y agravamiento de las amenazas antropogénicas estudiadas.

El pinsapo es una reliquia botánica del Terciario que persiste en un singular ecosistema de montaña. Es una especie endémica e insólita en el paisaje andaluz, por lo que se halla muy protegida y es objeto de una estrategia de conservación activa que pretende mitigar los efectos negativos del cambio global. En este artículo utilizamos 180 imágenes del sensor MODIS para desarrollar un análisis interanual y de tendencia estacional del NDVI promedio mensual, desde 2002 hasta 2016, de las superficies cubiertas por pinsapos. De acuerdo con los resultados obtenidos, se ha producido un incremento generalizado del NDVI en las masas forestales con presencia del pinsapo. La tendencia fue significativa en casi todos los tipos de formaciones y grados de cobertura. Esto sugiere una regeneración de los pinsapares en el marco de la estrategia de conservación activa. Sin embargo, detectamos un adelanto del Green up, hecho que podría estar relacionado con el calentamiento global.

Desertification is recognized as the land degrada - tion in arid, semiarid, and dry sub-humid zones, as a result from multiple anthropogenic impacts such as unsustainable natural resources management and land-use. In this context, the plant cover displays a crucial role due its capacity of soil protection against both terrestrial runoff and high rates of rain infiltration. In Brazil, the desertification has reached mainly the Seasonally Dry Tropical Forest ( STDF ) biome, natively known as Caatinga, in which the major drivers are related to the historical severe deforestation and livestock expansion. In face of this alarming scenario, there is no or few information about direct effects driven by desertifica - tion, particularly those related to the floristic composition of affected areas or affected potentially areas. Herein, the aim was to assess the desertification effects on vegetation composition within three sites in the Brazilian semiarid zone. In order to ensure unbiased comparisons, the three sampling sites presented similar topographical, pedological and climate conditions, localized at distinctive municipality from Paraíba State, Northeastern region, Brazil. In each site, two contrasting situations were sampled, - desertified and non-desertified environments. These environments were previously selected though satellite images, using the NDVI technique, for identification of vegetation biomass level. In field, the floristic composition was surveyed by transect method, covering a patch of 50m x 4m delimitated with me - tric tape. In these perimeters, it was identified the specie and botanical family of each plant, richness (S) and abundance (N) of tree with DBH ≥ 10 cm. Posteriorly, it was calculated the Shannon’s diversity (H’) and Piellou ́s evenness (J’) by Primer software (open access). Non-parametric univariate (U test) and multivariate (nMDS) analysis were performed to verify differences in the vegetational variables (S, N, H’ and J’) and to demonstrate dissimilarities patterns (relative abundance) for the contrasting environments, respectively. In total, twenty-six plant species were identified, belonging to thirteen families. Of this set, seventeen species (65%) were exclusive of non-desertified areas and only two species were exclusive of desertified areas. U test showed that the both richness and diversity of plants species differed signi - ficantly between the two analyzed environments. Using a subset of 10 species most common in two environments, the nMDS discriminated three groups of plants: i) species asso - ciated to non-desertified areas ( Anadenanthera columbrina, Bauhinia cheilantha and Tabebuia impetiginosa ), ii) species related to desertified areas ( Aspidosperma pyrifolium, Jatropha molissima, Mimosa tenuiflora and Pilosocereus gouneleii ) and iii) species with high density in both environments ( Croton sonderianus, Piptadenia stipulacea e Poincianella pyrami - dalis ). Dominant species in the non-desertified areas are restricted to the environments better preserved of Caatinga, which cannot to support strong degradation condition, whereas the species most common in the desertified areas are recognized as pioneer for the biome. Occurring to the two environments, such species harbors high capacity of settlement to the either impacted or preserved environments coupled to a strong resistance and resilience to disturbance (e.g. log and burn). Finally, the results obtained pointed out that the desertification triggered pervasive changes on the vegetational components (richness and diversity) and floristic composition of the Caatinga biome, suggesting also that human-induced disturbances were determinants to the establishment of the different environments.

Se estudia el bosque de sabinar o «bosque de naves» de Juniperus phoenicea subsp. turbinata (Guss.) Nyman de la Reserva Biológica de Doñana (RBD), en el entorno de las lagunas de Charco del Toro (CHT) y Navazo del Toro (NVT) utilizando el Método de Inventario de Fanerófitos y Caméfitos (MIFC). Se identifican cinco grupos de sabinares en función de sus elementos constitutivos y la estructura vertical y horizontal (cobertura). Geobotánicamente los sabinares se relacionan con los mantos eólicos litorales de Doñana que tienen una alta conductividad hidráulica y ausencia de una dinámica hídrica subsuperficial. El grupo considerado como formación sabinar-tipo se localiza en el Alto Manto Eólico Seco (AMEs) en el paraje del sabinar de El Ojillo (Grupo 1: NVTv 19). [fr] La forêt de genévriers ou forêt de navires de Juniperus phoenicea subsp. turbinata (Guss.) Nyman a été caractérisée dans la Réserve Biologique de Doñana (RBD) en utilisant une méthodologie d’inventaire végétal en transects linéaires considérant des phanérophytes et des chamaephytes (MIFC) dans le voisinage des lagunes de Charco del Toro (TCS) et Navazo del Toro (NVT). Cinq groupes de genévriers ont été identifiés en fonction de leurs éléments constitutifs et de leurs variables de structure verticale et horizontale (couverture), liés du point de vue géobotanique aux unités de manteaux éoliens de Doñana et au comportement de haute tranmissivité et à la dynamique hydrique du sous-sol des formations superficielles sur lesquelles ils sont distribués. Le groupe considéré comme la formation de genévriers type est situé dans le Haut Manteau Éolien Sec (HMES) dans la contrée du genévrier de El Ojillo (Groupe 1 : NVTv 19).

Se presenta un Método geobotánico cuantitativo de Inventario de formaciones vegetales homogéneas (Fanerófitos y Caméfitos) (método MIFC). La técnica utilizada es un inventario de vegetación (fanerófitos y caméfitos) en transectos lineales de 50x2 m, dando lugar a parcelas de 0,1 has, atributos y posición relativa de la vegetación a lo largo del transecto. El método considera como base analítica del estudio de la vegetación, 10 parcelas de muestreo. Los resultados proporcionan datos sobre la biodiversidad (Shannon, Simpson), factores mesológicos e índice de valor de importancia (IVI) ecológica. Finalmente el método MIFC desarrolla una representación gráfica estructural específica, consistente en el «Diagrama Ecodinámico de Riqueza-Estructura-Cobertura » (DEREC) para la vertical y en un «Diagrama de Burbujas» (DB) para la horizontal. [fr] Nous présentons ici une méthode géobotanique quantitative d’Inventaire de formations végétales homogènes (Phanérophytes et Chamaephytes) (méthode MIFC). La technique utilisée est un inventaire de la végétation (phanérophytes et chamaephytes) des transects linéaires de 50x2 m, donnant lieu à des parcelles de 0,1 ha, à des attributs et à une position relative de la végétation au long du dit transect. La méthode prende comme base d’analyse de l’étude de la végétation 10 parcelles d’échantillonnage. Les résultats fournissent des données sur la biodiversité (Shannon, Simpson), les facteurs mésologiques et l’Indice de Valeur d’Importance (IVI) écologique. Finalement, la méthode MIFC développe une représentation graphique structurelle spécifique consistant en un Diagramme Ecodynamique de Richesse-Structure-Couverture (DERSC) pour la verticale et en un Diagramme à bulles (DB) en horizontal.