3 research outputs found
Vegetation and plant diversity pattern study of Central Eastern Niger grasslands
Vegetation and plant diversity patterns of Central Eastern Niger grasslands were investigated following phytosociological methods. Vegetation data collected on 76 plots by using the Braun-Blanquet’s (1932) coverabundance scale were analyzed through five multivariate analyses (TWINSPAN, NMS, DCA, ISA and MRPP) in order to distinguish and to describe plant communities. Alpha diversity (H’, E and R) was also used to describe these communities. A total of 162 species belonging to 37 families and 104 genera were identified. Dominant families were the Poaceae (18%), Leguminosae-Papilionoideae (8%), Convolvulaceae (7%) and Leguminosae-Caesalpinioideae (4%). Life forms were dominated by Therophytes (59%) and Phanerophytes (27%), whereas the most prominent geoelements were of the Soudano-zambesians-saharo-sindians (33%), Soudano-zambesians (25%) and Guineo-congolian-soudano-zambesians (25%) types. In total, five plant communities were identified on the basis of environmental gradients and species composition. The environmental parameters that favorably influence these plant distributions are topography, moisture, texture and land use (fallow, pasture). Importantly, each of these communities seems to correspond to a particular wildlife habitat. These habitats shelter their own species that may be seen as a keystone species.Keywords: Multivariate analysis, vegetation communities, characteristic species, Central East grassland, Nige
Foncier et désertification, quelle gestion patrimoniale ? : approche foncière environnementale pour un développement durable au Sahel
Expert consensus document:Cholangiocarcinoma: current knowledge and future perspectives consensus statement from the European Network for the Study of Cholangiocarcinoma (ENS-CCA)
Cholangiocarcinoma (CCA) is a heterogeneous group of malignancies with features of biliary tract differentiation. CCA is the second most common primary liver tumour and the incidence is increasing worldwide. CCA has high mortality owing to its aggressiveness, late diagnosis and refractory nature. In May 2015, the "European Network for the Study of Cholangiocarcinoma" (ENS-CCA: www.enscca.org or www.cholangiocarcinoma.eu) was created to promote and boost international research collaboration on the study of CCA at basic, translational and clinical level. In this Consensus Statement, we aim to provide valuable information on classifications, pathological features, risk factors, cells of origin, genetic and epigenetic modifications and current therapies available for this cancer. Moreover, future directions on basic and clinical investigations and plans for the ENS-CCA are highlighted