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[Notes_IRSTEA]Chapter 20 [Departement_IRSTEA]Territoires [TR1_IRSTEA]SEDYVIN; International audience; This chapter explores the management objectives and the different approaches to wildlife management of large ungulates in France. A detailed analysis is done about the species present, their numerical status and the distribution of the different ungulates that occur. Management systems are described (legislative and administrative structures) with an evaluation of the current management practices.

Since 1980, researchers and managers have tried to develop new methods based on indicators of ecological changes to monitor deer populations. In that way, roe deer browsing rate on naturally regenerated oak seedlings may be a relevant method. This possibility is investigated since 1996 in a sessile oak forest (TEE de Trois Fontaines - Marne / France). This forest is enclosed (1 364 ha) and roe deer density is estimated by mark-resighting method (Lincoln Index). During an increasing period of the roe deer population density, a positive correlation between oak browsing rate and roe deer density has been observed (r²=0.910). Future work should be dedicated after this first promising result., En France, le plan de chasse constitue l'outil légal de gestion des populations de Chevreuil. Depuis la fin des années soixante dix, chercheurs et gestionnaires ont cherché à développer des méthodes indiciaires destinées à faciliter sa mise en ½uvre. Parmi les indicateurs couramment utilisés figurent l'indice d'abondance, la masse corporelle des chevrillards, l'indice de pression sur la flore. Dans ce contexte, cet article s'intéresse à la possibilité de proposer un nouvel indicateur d'abondance applicable au cas particulier des forêts de plaine à dominante de Chêne. Il étudie dans le cas spécifique de la sylviculture régulière par voie de régénération naturelle, la relation entre le niveau d'aboutissement de semis de Chêne et l'effectif de la population de Chevreuil. L'étude concerne la population de Chevreuil du Territoire d'Etude et d'Expérimentation de Trois Fontaines (51) dont l'effectif est estimé par la méthode de Capture-Marquage-Recapture. Sur une période de huit années, correspondant à une phase d'accroissement régulière de la population, l'indice d'abroutissement du Chêne suit étroitement l'augmentation du cheptel de Chevreuil. Ce résultat encourageant incite à la poursuite d'investigations complémentaires indispensables à la validation de cet indice.

Rheological properties of electrode slurries have been intensively studied for manifold different combinations of active materials and binders. Standardly, solvent-based systems are under use, but a trend towards water-based electrode manufacturing is becoming more and more important. The different solvent is beneficial in terms of sustainability and process safety but is also accompanied by some disadvantages such as extraction of residual humidity and a higher complexity concerning slurry stability. Li4Ti5O12 (LTO) active material provides good long-term stability and can be processed in aqueous solutions. Combining the LTO active material with sodium alginate (SA) as a promising biobased polymer binder reveals good electrochemical properties but suffers from bad slurry stability. In this work, we present a comprehensive rheological study on material interactions in anode slurries consisting of LTO and SA, based on a complex interaction of differentially sized materials. The use of two different surfactants—namely, an anionic and non-ionic one, to enhance slurry stability, compared with surfactant-free slurry.

A copper current collector is treated by electrolytic deposition of copper dendrites at the surface of the foil. This treatment results in a more structured surface leading to an improved contact between the electrode materials and the current collector. The contact to the electrode material particles of different sizes is investigated. Active materials of submicron size exhibit a drastically reduced internal resistance and a clearly improved C-rate capability. BET surface area measurement and calculation of roughness factor resulted in the finding of dendritic copper foil to provide an 8-fold larger surface area compared to the untreated foil. A comprehensive electrochemical impedance spectroscopy study is conducted for elucidation of electrochemical utilisation of the surface area increase. As a result, both fitting parameters for capacitance and surface resistance correspond to a similar normalization shift, indicating a clear improvement in the electro-active interface area.

In this study, Li4Ti5O12 (LTO) electrodes with different types of water-soluble binders are successfully coated upon aluminum foil. Electrodes containing solely sodium alginate (SA) as a binder or a mixed PVDF/carboxymethyl cellulose (CMC) binder show the most stable performance in 1 M LiPF6 in EC/DMC 1:1 in half cell vs. Li, with respect to cycle stability over 100 cycles at 1 C. The electrodes processed with a mixture of PVDF/SA show considerable fading and slightly worse values for rate capability. Each one of the different binders used is eco-friendly, and the whole processing can be performed without the use of organic solvents. Further advantages covering the whole production and recycling process, as well as safety issues during operation, encourage deeper research in this area.