Search results for "forest"
showing 10 items of 3780 documents
Molecular evidence for ongoing complementarity and horizontal gene transfer in endosymbiotic systems of mealybugs
2014
[EN] Intracellular bacterial supply of essential amino acids is common among sap-feeding insects, thus complementing the scarcity of nitrogenous compounds in plant phloem. This is also the role of the two mealybug endosymbiotic systems whose genomes have been sequenced. In the nested endosymbiotic system from Planococcus citri (Pseudococcinae), “Candidatus Tremblaya princeps” and “Candidatus Moranella endobia” cooperate to synthesize essential amino acids, while in Phenacoccus avenae (Phenacoccinae) this function is performed by its single endosymbiont “Candidatus Tremblaya phenacola.” However, little is known regarding the evolution of essential amino acid supplementation strategies in oth…
Impervious Surfaces Alter Soil Bacterial Communities in Urban Areas: A Case Study in Beijing, China
2018
The rapid expansion of urbanization has caused land cover change, especially the increasing area of impervious surfaces. Such alterations have significant effects on the soil ecosystem by impeding the exchange of gasses, water, and materials between soil and the atmosphere. It is unclear whether impervious surfaces have any effects on soil bacterial diversity and community composition. In the present study, we conducted an investigation of bacterial communities across five typical land cover types, including impervious surfaces (concrete), permeable pavement (bricks with round holes), shrub coverage (Buxus megistophylla Levl.), lawns (Festuca elata Keng ex E. Alexeev), and roadside trees (S…
Les micromammifères du département de l'Isère (Rhône-Alpes, France) : répartition par district naturel.
2013
Micromammals of the French department of Isère (Rhône-Alpes) : distribution by natural district. - This article presents the distribution of the species of micromammals of the department of Isère (Rhône-Alpes, France), by natural district from the analysis of 78,100 specimens inventoried and registered in a database of the micromammals of the department. For each species, a comparison of its distribution is made between districts. This synthesis is a photograph of the current knowledge and it also allows to define the future researches to improve the knowledge and the protection of micromammals in Isère.
Syntaxonomy and ecology of thermophilous deciduous open woodlands and scrub vegetation in Tajikistan (Middle Asia)
2022
In this paper we present the first syntaxonomic classification for the thermophilous open wood and scrub vegetation in Tajikistan with some remarks on its environmental gradients. Altogether 143 relevés were sampled between 2014–2021 using the seven-degree cover-abundance scale of Braun-Blanquet. They were classified by the modified TWINSPAN method with the use of the four step interval scale with cutoff levels of 0%, 2%, 5% and 10% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Detrended Correspondence Analysis was used to determine the relation between samples, vegetation units and the major grad…
Sviluppo di modelli innovativi per il monitoraggio multiscala degli indicatori di servizi ecosistemici nelle foreste Mediterranee (Progetto MIMOSE).
2013
Gli ecosistemi, attraverso le loro funzioni, forniscono un ampio range di beni e servizi, che risultano fondamentali per il benessere dell’uomo. Questi vengono complessivamente definiti Servizi Ecosistemici (SE). I SE possono essere intesi come un flusso di valori verso la società, quale risultato dello stato e della quantità del capitale naturale disponibile. Il mantenimento degli stocks del capitale naturale può permettere di prevedere i flussi futuri dei SE, assicurando quindi il benessere dell’uomo per le generazioni future. Il progetto FIRB 2012 MIMOSE è finalizzato allo sviluppo di un approccio multiscala innovativo e all’implementazione di strumenti previsionali volti al monitoraggio…
Dinamiche dell’uso e delle coperture del suolo dell’ultimo mezzo secolo nel paesaggio forestale siciliano.
2014
Il lavoro è stato realizzato nell’ambito dell’Azione 3 del progetto LIFE11 ENV IT 215 “RESILienza al cambiamento climatico nelle FOReste MEDiterranee”. In particolare, è stato implementato un sistema di monitoraggio attraverso indagini diacroniche sui principali contesti territoriali pre-forestali e forestali della Sicilia. L’analisi è stata condotta a livello di paesaggio in sei distretti forestali, rappresentativi delle principali categorie forestali della regione, quali i Sicani, le Madonie, i Nebrodi, l’Etna, l’area del Calatino (Sicilia SO) e l’isola di Pantelleria. L’analisi condotta ha come obiettivo il cambiamento dell’uso e delle coperture del suolo avvenuti nel corso dell’ultimo s…
A satellite stand-alone procedure for deriving net radiation by using SEVIRI and MODIS products
2018
Abstract In this study, a new stand-alone satellite approach for the estimation of net surface radiation (Rn) has been implemented and validated for the Italian territory. The method uses the MODIS and MSG-SEVIRI time series products and it is independent of the use of ancillary data (i.e. ground measurements). A database of daily measurements of Rn, provided by 9 stations of the FLUXNET network, was used to validate the method in different ecological scenarios in the period 2010-12. The Rn modelled by the proposed approach and the corresponding FLUXNET measurements were in good agreement, with RMSE and R2 of 19.8 Wm−2 and 0.87, respectively, at 8-days scale, and 23.3 Wm−2 and 0.92, respect…
Measuring basal soil respiration across Europe: Do incubation temperature and incubation period matter?
2014
The European Commission recognises the essential role of soil biology in soil functioning and delivery of ecosystem services, but information is currently lacking evaluate of how these vary across soil and land-use types at a European scale. This study evaluated the measurement of the initial rate of soil basal respiration (BR) as a potential biological indicator of ecosystem service provision. The purpose of this study was to test ISO 16072:2002 (Soil Quality: Laboratory methods for the determining of microbial soil respiration). In the literature a range of pre-incubation temperatures (pre-inc) and experimental incubation temperatures (exp-inc) have been applied when using the ISO method …
Dynamique et modélisation des crues dans le bassin du Mono à Nangbéto (Togo/Bénin)
2014
Les inondations des dernières années en Afrique de l'Ouest rendent nécessaire la prévision hydro-logique pour réduire la vulnérabilité des populations. Nous avons étudié la dynamique des crues dans le bassin du Mono en amont du barrage de Nangbéto (Togo et Bénin) par des méthodes statistiques et déterministes. L'augmentation des précipitations au cours de la décennie 1990 et la mise en eau du barrage de Nangbéto en 1988 ont modifié le régime du Mono, dont les débits d'étiages ont augmenté. Les débits entrants et sortants du barrage sont équivalents, même lors des crues. Les maximums annuels des débits entrants peuvent être modélisés par une distribution des valeurs extrêmes (GEV) de type Fr…