Search results for "decision"
showing 10 items of 2091 documents
A new tool for the assessment of severe anthropogenic eutrophication in small shallow water bodies
2017
Abstract Unlike in deep stratified lakes, the assessment of eutrophication in shallow aquatic systems (i.e., wetlands, marshes, ponds) should be based on the interaction between water and sediment. The availability of P to primary producers is naturally higher in shallow systems, because the sediment plays an active part via adsorption, precipitation and release processes. Thus, many wetlands in protected areas are naturally eutrophic and have a high trophic status due to intrinsic features and thus, display a high concentration of total-P in the water without necessarily implying pollution or poor quality. We have provided a diagnostic tool based on the chemical equilibrium of dissolved re…
Does air pollution influence the success of species translocation? Trace elements, ultrastructure and photosynthetic performances in transplants of a…
2020
Abstract Species translocation can be considered as a primary conservation strategy with reference to in situ conservation. In the case of lichens, translocations often risk to fail due stress factors associated with unsuitable receptor sites. Considering the bioecological characteristics of lichens, air pollution is among the most limiting stress factors. In this study, the forest macrolichen Lobaria pulmonaria was used as a model to test the hypothesis that the translocation of sensitive lichens is effective only in unpolluted environments. At purpose, 500 fragments or whole thalli were translocated in selected beech forests of Central Europe (the Western Carpathians, Slovakia) where the …
Modelling the European Farmland Bird Indicator in response to forecast land-use change in Europe
2011
International audience; The European Farmland Bird Indicator (EFBI) has been adopted as a Structural and Sustainable Development Indicator by the European Union. It is an aggregated index integrating the population trends of 33 common bird species associated with farmland habitats across 21 countries. We describe a modelling method for predicting this indicator from land-use characteristics. Using yearly historical land-use data of crop areas derived from the FAO databases (1990–2007) and published population data of farmland birds at the national level for the same period, we developed a series of multiple regression models to predict the trend of the EU state specific indicator, and the E…
A bark beetle infestation predictive model based on satellite data in the frame of decision support system TANABBO
2020
The European spruce bark beetle Ips typographus L. causes significant economic losses in managed coniferous forests in Central and Northern Europe. New infestations either occur in previously undisturbed forest stands (i.e., spot initiation) or depend on proximity to previous years’ infestations (i.e., spot spreading). Early identification of newly infested trees over the forested landscape limits the effective control measures. Accurate forecasting of the spread of bark beetle infestation is crucial to plan efficient sanitation felling of infested trees and prevent further propagation of beetle-induced tree mortality. We created a predictive model of subsequent year spot initiation and spo…
LTSER platforms as a place-based transdisciplinary research infrastructure: learning landscape approach through evaluation
2019
Context: Place-based transdisciplinary research involves multiple academic disciplines and non-academic actors. Long-Term Socio-Ecological Research (LTSER) platform is one concept with ~ 80 initiatives globally. Objectives: As an exercise in learning through evaluation we audited (1) the siting, construction and maintenance of individual LTSER platforms, and (2) them as a distributed infrastructure for place-based transdisciplinary research with focus on the European continent. Methods: First, we defined a normative model for ideal performance at both platform and network levels. Second, four surveys were sent out to the 67 self-reported LTSER platforms officially listed at the end of 2016.…
Why do house-hunting ants recruit in both directions?
2007
8 pages; International audience; To perform tasks, organisms often use multiple procedures. Explaining the breadth of such behavioural repertoires is not always straightforward. During house hunting, colonies of Temnothorax albipennis ants use a range of behaviours to organise their emigrations. In particular, the ants use tandem running to recruit na? ants to potential nest sites. Initially, they use forward tandem runs (FTRs) in which one leader takes a single follower along the route from the old nest to the new one. Later, they use reverse tandem runs (RTRs) in the opposite direction. Tandem runs are used to teach active ants the route between the nests, so that they can be involved qui…
Reciprocal extrapolation of species distribution models between two islands – Specialists perform better than generalists and geological data reduces…
2020
Abstract This study aims to test the extrapolation effects of species distribution models (SDM) using three groups of predictor variables: climate, relief and geology (bedrock type). We highlight potential ecological differences for selected taxa, regarding both generalists and specialists in terms of edaphic conditions. We used distributional data of 12 woody species shared by two large Mediterranean islands (Crete and Sicily) to calibrate Maxent models of their potential distribution. We trained models with data from Crete and extrapolated to Sicily and vice versa. We tested ten proxies for the three variable groups and compared AUC values as a measure of model performance. Extrapolation …
The challenge of habitat modelling for threatened low density species using heterogeneous data: The case of Cuvier’s beaked whales in the Mediterrane…
2018
We are grateful to the ACCOBAMS Secretariat for their support in this work, including a small grant for the analysis. The Mediterranean population of Cuvieŕs beaked whale (Ziphius cavirostris), a deep-diving cetacean, is genetically distinct from the Atlantic, and subject to a number of conservation threats, in particular underwater noise. It is also cryptic at the surface and relatively rare, so obtain robust knowledge on distribution and abundance presents unique challenges. Here we use multiplatform and multiyear survey data to analyse the distribution and abundance of this species across the Mediterranean Sea. We use a novel approach combining heterogeneous data gathered with different …
Assessment of surface sediment dynamics and response of benthic macrofauna assemblages in Boughrara Lagoon (SW Mediterranean Sea)
2016
International audience; A study was conducted in the spring of 2009, the winters of 2010 and 2013, and in the summer of 2012 at 13 stations in Boughrara Lagoon, Tunisia (southern Mediterranean). The country’s largest lagoon, it is considered to be an anthropogenically stressed area, though a major tourist centre—Djerba Island—is located along its northern shores. The lagoon bottoms were studied via analyses of grain size, surface sediment composition, total organic matter (TOM) and through the trophic and functional organisation of benthic macrofauna. The results indicate that the bottoms are composed of fine, medium or coarse sands and that sediment distribution is controlled by water move…
The analysis of convergence in ecological indicators: An application to the Mediterranean fisheries
2017
9 pages, 4 figures, 3 tables