{"id":459,"date":"2019-05-17T14:52:13","date_gmt":"2019-05-17T12:52:13","guid":{"rendered":"http:\/\/sources-diatomees.univ-bpclermont.fr\/?p=459"},"modified":"2019-05-17T14:54:56","modified_gmt":"2019-05-17T12:54:56","slug":"la-reserve-naturelle-de-chastreix-sancy","status":"publish","type":"post","link":"https:\/\/sources-diatomees.geolab.uca.fr\/?p=459","title":{"rendered":"La R\u00e9serve Naturelle de Chastreix Sancy"},"content":{"rendered":"<p>Depuis l&rsquo;\u00e9t\u00e9 2017, diff\u00e9rentes campagnes d&rsquo;\u00e9tude se sont succ\u00e9d\u00e9es dans la R\u00e9serve Naturelle Nationale de Chastreix-Sancy. La RNN couvre le versant sud du Sancy et englobe le cirque glaciaire de Fontaine Sal\u00e9e. Dans son emprise, diff\u00e9rentes sources ont \u00e9t\u00e9 r\u00e9pertori\u00e9es depuis des sources banales (peu min\u00e9ralis\u00e9es et jaillissant\u00a0majoritairement\u00a0\u00e0 la faveur de rupture de pente) jusqu&rsquo;\u00e0 des sources min\u00e9rales p\u00e9tillantes et ferrugineuses.<\/p>\n<p>En juin 2017, 14 sources ont \u00e9t\u00e9 \u00e9tudi\u00e9es: analyses physico-chimiques et inventaire des esp\u00e8ces de diatom\u00e9es pr\u00e9sentes. Dans un contexte de roches acides, la conductivit\u00e9 la plus \u00e9lev\u00e9e a \u00e9t\u00e9 observ\u00e9e \u00e0 la source du Bois de la Masse (1110 \u00b5S\/cm) et dans la source de la Fontaine sal\u00e9e (621 \u00b5S\/cm).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-463\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/P1040948-1024x768.jpg\" alt=\"\" width=\"197\" height=\"148\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040948-1024x768.jpg 1024w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040948-300x225.jpg 300w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040948-768x576.jpg 768w\" sizes=\"auto, (max-width: 197px) 100vw, 197px\" \/>\u00a0\u00a0\u00a0\u00a0 <img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-464\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/P1040931-1024x768.jpg\" alt=\"\" width=\"196\" height=\"147\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040931-1024x768.jpg 1024w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040931-300x225.jpg 300w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040931-768x576.jpg 768w\" sizes=\"auto, (max-width: 196px) 100vw, 196px\" \/><\/p>\n<p>Les conductivit\u00e9s les plus basses (&lt;\u00a020 \u00b5S\/cm) ont \u00e9t\u00e9 mesur\u00e9es sur les cr\u00eates du Massif du Sancy (Tarafet, Col de la cabane et Tour carr\u00e9e; photos ci-dessous). Dans ces sources peu min\u00e9ralis\u00e9es, l&rsquo;esp\u00e8ce oubli\u00e9e\u00a0<em>Cocconeis rouxii<\/em> a notamment \u00e9t\u00e9 observ\u00e9e (Wetzel et al. 2019).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-460\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/P1040886-1024x768.jpg\" alt=\"\" width=\"191\" height=\"144\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040886-1024x768.jpg 1024w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040886-300x225.jpg 300w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040886-768x576.jpg 768w\" sizes=\"auto, (max-width: 191px) 100vw, 191px\" \/>\u00a0\u00a0\u00a0 <img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-461\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/P1040890-1024x768.jpg\" alt=\"\" width=\"191\" height=\"143\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040890-1024x768.jpg 1024w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040890-300x225.jpg 300w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040890-768x576.jpg 768w\" sizes=\"auto, (max-width: 191px) 100vw, 191px\" \/>\u00a0 <img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-462\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/P1040906-1024x768.jpg\" alt=\"\" width=\"191\" height=\"143\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040906-1024x768.jpg 1024w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040906-300x225.jpg 300w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/P1040906-768x576.jpg 768w\" sizes=\"auto, (max-width: 191px) 100vw, 191px\" \/><\/p>\n<p>Des esp\u00e8ces nouvelles appartenant par exemple aux genres <em>Aulacoseira<\/em>, <em>Cymbopleura<\/em> et <em>Pinnularia\u00a0<\/em>ont \u00e9t\u00e9 observ\u00e9es et seront d\u00e9crites.<\/p>\n<p>De plus, outre les sources, une mare temporaire impact\u00e9e par la pr\u00e9sence de troupeaux en \u00e9t\u00e9 (concentration en ammonium pouvant atteindre 23 mg\/l en juillet) est \u00e9tudi\u00e9e depuis 2017. Cette mare produit des pr\u00e9cipitations et de la fonte des neige, disparait en \u00e9t\u00e9. Les communaut\u00e9s de diatom\u00e9es se d\u00e9veloppant dans cette mare peuvent donc supporter de forts changements de min\u00e9ralisation avec des apports en azote tr\u00e8s \u00e9lev\u00e9s. C&rsquo;est le cas de <em>Pinnularia<\/em> sp. :<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-466\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp.jpg\" alt=\"\" width=\"105\" height=\"172\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp.jpg 567w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp-183x300.jpg 183w\" sizes=\"auto, (max-width: 105px) 100vw, 105px\" \/>\u00a0\u00a0 <img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-467\" src=\"http:\/\/sources-diatomees.univ-bpclermont.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp-b.jpg\" alt=\"\" width=\"105\" height=\"172\" srcset=\"https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp-b.jpg 568w, https:\/\/sources-diatomees.geolab.uca.fr\/wp-content\/uploads\/2019\/05\/Pinnularia-sp-b-183x300.jpg 183w\" sizes=\"auto, (max-width: 105px) 100vw, 105px\" \/><\/p>\n<p>Des analyses des \u00e9l\u00e9ments traces ont \u00e9t\u00e9 r\u00e9alis\u00e9s en novembre 2018 \u00e0 la source de la Fontaine sal\u00e9e (cf. article:\u00a0\u00a0\u00ab\u00a0Projet FRE: Mesures physico-chimiques et isotopiques avec le BRGM\u00a0\u00bb ) et des analyses de radioactivit\u00e9 en mai 2019 (cf article: \u00ab\u00a0Echantillonnage de sources dans la Zone-Atelier \u00ab Territoires Uranif\u00e8res dans l\u2019Arc Hercynien \u00bb\u00a0\u00bb).<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Depuis l&rsquo;\u00e9t\u00e9 2017, diff\u00e9rentes campagnes d&rsquo;\u00e9tude se sont succ\u00e9d\u00e9es dans la R\u00e9serve Naturelle Nationale de Chastreix-Sancy. La RNN couvre le versant sud du Sancy et englobe le cirque glaciaire de Fontaine Sal\u00e9e. Dans son emprise, diff\u00e9rentes sources ont \u00e9t\u00e9 r\u00e9pertori\u00e9es depuis des sources banales (peu min\u00e9ralis\u00e9es et jaillissant\u00a0majoritairement\u00a0\u00e0 la faveur de rupture de pente) jusqu&rsquo;\u00e0 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":471,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-459","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-non-classe"],"_links":{"self":[{"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/posts\/459","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=459"}],"version-history":[{"count":2,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/posts\/459\/revisions"}],"predecessor-version":[{"id":470,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/posts\/459\/revisions\/470"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=\/wp\/v2\/media\/471"}],"wp:attachment":[{"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=459"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=459"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sources-diatomees.geolab.uca.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=459"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}