Blog da Associação Trilhos d'Esplendor.

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(contains Web links to Flora-On for observed plant species, Web links to high resolution Google satellite-maps (JPG) of plant-hunting regions from the Iberian peninsula; illustrated text in Portuguese language)



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quarta-feira, 2 de outubro de 2013

2.13.2c4 - Ambientes aquáticos - Serra da Estrela



“Flowers of South-West Europe - a field guide” - de Oleg Polunin e B.E. Smythies


“Revisitas” de regiões  esquecidas no tempo - “Plant Hunting Regions” - a partir de uma obra de grande valor para o especialista e amador de botânica como da Natureza em geral.


Por
Horst Engels, Cecilia Sousa, Luísa Diniz, Nicole Engels, José Saraiva, Victor Rito
da
Associação “Trilhos d’Esplendor”


2.13 The Northern Serras of Portugal



2.13 As Serras do Norte de Portugal
2.13.2 Serra da Estrela
      1. Geografia, Clima, Geologia, Geomorfologia e Solos
      2. Bioclima, Biogeografia, Vegetação actual e potential
      3. Zona de Baixa Altitude (meso-temperada e meso-medetirrânica)
      1. Zona de Média Altitude (supra temperada e supra-mediterrânica)
      2. Zona de Alta Altitude (oro-temperada)
    1. Os Habitats da Serra da Estrela
      1. Ambientes aquáticos
        1. Lagoas
        2. Fontes (springs)
        3. Correntes de água (streams)
        4. Águas paradas (standing waters)
        5. Charcos e biotopes temporariamente inundadas (seasonally inundated biotopes
        6. Turfeiras (bogs)
      2. Ambientes rochosos
      3. Habitats rurais
    2. Aspectos glaciários da Serra da Estrela
    3. “Cultural Landscapes of Europe” - Serra da Estrela, uma paisagem tradicional
      1. Mudança climática e sucessão vegetational no Holocénico
      2. Acção antropogénica e degradação florestal no Holocénico
      3. Um modelo para a gestão da Serra da Estrela
    4. A Fauna da Serra da Estrela
      1. Observação de Aves na Serra da Estrela
      1. O Sítio Estrela
      2. Lista dos Habitats
      3. Introdução à Bioclimática
      4. Introdução à Biogeografia
      5. Introdução à Fitossociologia
Folha de Cálculo: Flora da Serra da Estrela
(Lista provisória de plantas vasculares e não-vasculares)



Mapas das Serras do Norte de Portugal:


2.13.2 Serra da Estrela





Lagoa do Serrano - Planalto da Serra da Estrela




Ranunculus ?peltatus, perto da Lagoa Comprida na Pragueira (Serra da Estrela)


Ambientes aquáticos

Jan Jansen escreve em 2002 no “Geomorphological Guide of the Serra da Estrela” [1] sobre os ambientes aquáticos:


"As a result of the high precipitation in the Serra da Estrela, various freshwater environments exist. According to their stream velocity these may be subdivided into standing waters such as lakes, ponds, swamps or bogs, and running waters such as springs, brooks, and rivers. Other factors influencing aquatic flora and fauna include nutrient availability (oligotrophic, mesotrophic, eutrophic), nature of substratum (sand, silt, clay, rod), temperature, light availability, water depth, duration of inundation, acidity, oxygen availability, and other factors some of which are also interrelated by each other.
Plants may be classified according to their water requirements. The terminology associated with the water factor is built upon three simple prefixes of Greek roots: xero-, dry; hygro- (hydro), wet; and meso-, intermediate or middle. A biotope may be prevailing wet (hygric); prevailingly dry (xeric), or of intermediate degree of wetness (mesic). Those plants which grow in dry biotopes are xerophytes: those which grow in biotopes of intermediate degree of wetness and relatively uniform water availability are mesophytes.
Many plant species in standing waters and streams grow entirely in water. These are called hydrophytes. Free of most of their weight these water plants are flexible and pliant in the stream. Some are submerged, some float on the surface, others combine both strategies. They may be free-floating, anchored or rooted, mostly taking up oxygen and nutrients via their leaves. In all aquatic or semi-aquatic ecosystems helophytes can he found. Helophytes are always rooted in the soil and their stalks reach over the water level. Their stalks and leaves have a special tissue called aerenchym to transport oxygen from the air. This is important if there is shortage of oxygen in the soil, especially in swamps. Phytoplankton consists of floating producers (mainly algae) and zooplankten consists of floating consumers (e.g. water fleas). Both are a vital component in food chains (larger insects, fishes, birds, mammals)." (Jan Jansen, 2002, p. 145).


As Lagoas da Serra da Estrela


Devido às últimas glaciações, sobretudo da última glaciação Würm (há cerca de 20 milhões de anos), a Serra a Estrela possui também um elevado número de lagoas. Costa et.al. (2004) caracterizam as lagoas e a Serra da Estrela da seguinte forma: [2]



“O adjectivo único é utilizado frequentemente para qualificar sítios e áreas protegidas; porém, se  no  seu  conjunto  todos  os  sítios  são  únicos,  no  sentido  de  resultarem  de  uma  série  de factores  externos  e  locais,  que  determinaram  a  existência  de  valores  naturais  elevados  e singulares, a Serra da Estrela, mais do que nenhum outro sítio, merece esse adjectivo, pois o facto  de  ter  sido  o  único  local  do  território  de  Portugal  onde  ocorreram  fenómenos  de glaciação em larga escala, conferiu-lhe uma série de características que, aliadas à altitude e ao clima, são verdadeiramente únicas.


Este atributo “único” deve-se sobretudo à presença das lagoas glaciares e vales glaciares na Serra da Estrela que são de facto fenómenos únicos para Portugal. Existem lagoas glaciares também nas outras serras altas da Península Ibérica, como por exemplo na Cordilheira Cantâbrica, na Serra de Gredos e Guadarrama, nos Pirinéus e na Serra da Nevada. Mas Portugal apenas teve a Serra da Estrela como área largamente influenciada pelas glaciações.


Descrevemos as lagoas aqui mais pela sua beleza paisagística do que pelo valor botânico, uma vez que as águas oligotróficas contêm em geral poucas espécies de plantas vasculares. No entanto, nas margens das lagoas encontram-se muitas spécies de valor botânico.




Lagoa Comprida, Serra da Estrela




Lagoa Comprida, Serra da Estrela




Lagoa Comprida, Serra da Estrela




Granito da Lagoa Comprida




?Antinoria agrostidea subsp. natans - Lagoa Comprida (Serra da Estrela)




Comunidade de plantas (Isoeto-Littorelletia) nas margens da Lagoa Comprida (Serra da Estrela)  - com Juncus bulbosus, Juncus effusus  e Antinoria agrostidea..




Juncus bulbosus - Lagoa Comprida (Serra da Estrela)




Antinoria agrostidea - Lagoa Comprida (Serra da Estrela)




Antinoria agrostidea - Lagoa Comprida (Serra da Estrela)




Spergularia rubra - Lagoa Comprida (Serra da Estrela)




Spergularia rubra - Lagoa Comprida (Serra da Estrela)




Juncus effusus - Lagoa Comprida (Serra da Estrela)




Salix salviifolia - Lagoa Comprida (Serra da Estrela)




Salix salviifolia - Lagoa Comprida (Serra da Estrela)




Calluna vulgaris - Lagoa Comprida (Serra da Estrela)




Calluna vulgaris- Lagoa Comprida (Serra da Estrela)


Costa et.al. (2004) caracterizam as Lagoas da Serra da Estrela biologicamente da seguinte forma:


Enquadramento fitogeográfico


“A Reserva  Biogenética  da  Serra  da Estrela  ocupa  uma  área muito  especial  no  contexto continental  português  –  corresponde  a  um  território  que  se  estende  predominantemente acima  de  1600  metros  de  altitude,  cujas  condições  abióticas  condicionam  a  ocorrência  de características fitogeográficas muito próprias. A altitude determina condições bioclimáticas onde imperam as baixas temperaturas médias anuais, precipitações abundantes, com queda de neve durante seis meses e possibilidade de geadas praticamente durante todo o ano. Embora sem dados climáticos suficientes para uma caracterização completa (a única estação de observação contínua nos últimos decénios é a das Penhas Dourados, a uma altitude de 1383  metros,  na  periferia  da  Reserva Biogenética),  a  maior  parte  da Reserva  enquadra-se no macrobioclima temperado, piso orotemperado, hiper-húmido. Contudo, as zonas menos elevadas da Reserva não ultrapassam o supratemperado, igualmente hiper-húmido. As  diversas  lagoas  e  pequenos  lagoachos  da  Reserva  estão  sujeitos  a  este  contexto bioclimatológico. A sua flora e vegetação estão correlacionadas com a flora e vegetação de outras montanhas ibéricas mas também com a flora e vegetação de territórios centro-europeus cujas  características  bioclimáticas  se  apresentam  afins. Porém,  variáveis  como  dimensão, profundidade, natureza do substrato, altitude, exposição e outros tornam as mesmas distintas entre si, possibilitando a ocorrência de pequenos ambientes únicos, no contexto da própria serra. A identidade de cada pequena lagoa permite a ocorrência de habitats distintos proporcionando condições para diferentes espécies. O facto de muitas destas espécies se encontrarem no seu limite  meridional  de  distribuição  torna  as  populações  locais  eventualmente  susceptíveis  de diferenciação  merecendo uma  atenção  particular  do  ponto  de  vista  genético,  constituindo cada lagoa um pequeno laboratório vivo.” (Costa et.al. (2004, pp. 30-31)


A. Limnologia


“Estudos  levados a cabo em parte das  lagoas existentes no interior da Reserva Biogenética (Boavida & Gliwicz 1994) indicam que as mesmas são maioritariamente ácidas, com valores de pH entre 4,1 e 6,0, aparentemente como consequência da litologia granítica, não excluindo os autores a influência de outros factores. Aqueles estudos, realizados entre Agosto e Outubro de  1993, sugerem  que  se  tratam  de  lagoas  bem  oxigenadas  (OD>80%)  e  com  níveis  de transparência  elevados.  Por  seu  lado,  os  valores  de  clorofila  e  de  fosfatos  revelaram-se extremamente baixos, confirmando as características alpinas destes ambientes.
O fitoplâncton é dominado por algas unicelulares, não tendo sido detectadas cianobactérias no  período  em  que  decorreram  os  trabalhos  de  amostragem  da  equipa  referida.  Sendo  a diversidade destas comunidades muito reduzida.
As  comunidades  zooplantónicas  são  também  pouco  diversificadas  e  incluem  espécies  de cladóceros, copépodes e rotíferos. Em cada uma das lagoas amostradas havia um número reduzido de espécies, variando entre 4 e 8, e estando presentes de forma regular. Em termos percentuais  verificaram-se  algumas  diferenças  na  contribuição  de  cada  um  destes  grupos para  a  comunidade  zooplantónica,  havendo  lagoas  com  dominâncias  claras  de  rotíferos (Salgadeiras e Covão do Ferro), e lagoas em que as dominâncias não foram tão marcadas.
As  diferenças  verificadas  na  composição  destas  comunidades  e  mesmo  nas  características dos animais detectados, nomeadamente no que respeita às suas dimensões, poderão ser em parte  explicadas  pela  presença  de  peixes  planctívoros  em  algumas  das  lagoas  (Boavida  & Gliwicz 1994.)
Os autores do estudo acima referido concluem que as lagoas estudadas devem ser classificadas como oligotróficas.” (Costa et.al. (2004, pp. 29-30)


B. Plantas vasculares


“A  maioria  das  lagoas  e  lagoachos  da  Serra  da  Estrela  apresenta  uma  forte  presença  da associação Fontinali-Ranunculetum lusitanici. As suas espécies mais características são os ranúnculos (Ranunculus ololeucos = R. lusitanicus),  o  junco  Juncus bulbosus,  a  pequena gramínea  Antinoria agrostidea e a briófita Fontinalis antipyretica. A dominância destas espécies ou de outras igualmente enquadradas na Classe Isoeto-Littorelletea é em parte responsável pela identidade de cada lagoa.
Muitos dos lagoachos apresentam uma elevada dominância dos ranúnculos (Ranunculus ololeucos = R. Lusitanicus). Os mesmos chegam a cobrir a quase totalidade da superfície dos lagoachos mais pequenos, durante os meses primaveris. No entanto, próximo da margem surge quase sempre  Antinoria agrostidea ssp.  natans,  tão característica da Lagoa da Paixão, ou mesmo A. agrostidea subsp. agrostidea, mais comum na orla terrosa das lagoas. Juncos como Juncus bulbosus, J. heterophyllus e Juncus effusus surgem frequentemente na interface da margem. Briófitos  como  Fontinalis  antypiretica  e Drepanocladus  fluitans  são  extremamente  frequentes sobre substratos rochosos imersos. Outras espécies como Fontinalis squamosa e Scapania undulata, são também comuns tornando as comunidades briofíticas dominantes neste habitat. A presença de  plantas  vasculares  é menos  frequente,  abrindo  as  portas  para  a  associação  Sparganio angustifolii-Isoetetum lereschi, onde pontuam espécies raras como Sparganium angustifolium. Algumas  das  lagoas  e  lagoachos  são  alimentados  por  pequenos  regatos  permanentes pelo que  o  seu  nível  de  água  sofre variações pouco  significativas  ao  longo do ano. Formam-se assim condições para a presença de uma comunidade lacustre de margem, onde se assumem como  significativas  as  presenças  de  várias  espécies  de  esfagnos  (Sphagnum  compactum,  S. capillifolium,  S.  recurvum,  S.  denticulatum,  etc.)  característicos  da  associação  Junco  squarrosi-Sphagnetum compacti.  Este  tipo  de  comunidades  que  é  extremamente  interessante  pela  sua raridade  em Portugal  e  pela  vulnerabilidade  que  apresenta  a  acções  antrópicas,  ocorre  na maior parte das lagoas, embora em pequenas áreas. Nesta  comunidade  ocorrem  também  algumas  das  raridades  da  Estrela.  Espécies  muito características para além dos esfagnos são Carex nigra, C. echinata, Pedicularis sylvatica, Viola palustris  ssp.  juressi, Drosera  rotundifolia  e  mesmo Whalenbergia hederacea. Em zonas  um  tanto mais secas ocorrem ainda Nardus stricta, Potentilla erecta e Gentiana pneumonanthe. A  identidade  de  cada  lagoa  e  lagoacho  é  conseguida  não  apenas  do  ponto  de  vista geomorfológico  e  altitudinal  mas  também  ao  nível  da  flora  e  vegetação  que  comportam. Paradoxalmente, a Serra da Estrela comporta uma elevada diversidade de plantas e habitats mas, dada  a  sua posição  geográfica  e  a  sua  extensão,  essas  originalidades  biológicas  estão pouco representadas, ocupando grande parte das vezes extensões relativamente modestas. Como  aspectos  dessa  originalidade,  ao  nível  das  lagoas,  cite-se,  como  veremos  adiante,  a ocorrência  de  diversas  espécies muito  escassamente  representadas  em  Portugal  e  que  na Serra da Estrela são apenas conhecidas de uma única charca ou lagoa, numa faixa mínima de habitat ocupado. Nas lagoas a mais baixa altitude ocorre por vezes Potamogeton polygonifolius. Embora a sua distribuição no território português seja ampla, a sua presença é sempre pouco frequente e como tal é uma espécie que merece algum destaque. A sua presença ocorre, por exemplo na Lagoa Redonda, apontando para características distintas daquela, relativamente a outras charcas e lagoas. Nas charcas ocorre por vezes Sparganium angustifolium. Em Portugal apenas ocorre na Serra da Estrela, onde atinge o limite sul da sua distribuição. Trata-se de uma espécie de ampla distribuição no norte e centro da Europa mas que no sul se comporta como orófito. Geralmente ocorre em charcas pouco profundas que não secam ou que secam apenas numa curta estação do ano. A  cerca  de  1600  metros  de  altitude  ocorre  outra  raridade  curiosa. Trata-se  da  espécie Menyanthes trifoliata  (vulgarmente  designada  por  fava-de-água,  dada  a  semelhança  das  suas folhas com a conhecida leguminosa). A sua presença na Estrela confina-se a uma charca de pequenas dimensões - a Lagoa das Favas - numa área total de algumas dezenas de metros quadrados. No resto do país a sua população é igualmente muito restrita. Na Estrela, a sua presença  parece  depender da zona de  água permanente (pouco profunda), na  área  central da  referida  lagoa. Também junto de uma única lagoa está a recentemente descoberta população de Lycopodiella inundata. Apenas referida para o norte de Portugal, a sua descoberta amplia consideravelmente a sua área de distribuição no nosso país. Trata-se mais uma vez de uma espécie muito rara em Portugal e com uma distribuição mínima na Estrela, onde ocupa uma estreita faixa em redor de uma das maiores lagoas glaciárias. No  topo  das  raridades  e  infelizmente  em  risco  acentuado  de  extinção  encontra-se  o emblemático  Lycopodium  clavatum  (licopódio-da-estrela).  Para  além  de  constituir  a  única população portuguesa, a sua área de distribuição não ultrapassa os dois metros quadrados. Dada a perturbação do local e um aparente stress hídrico mais prolongado do que deveria, o seu futuro é incerto, a curto prazo.” (Costa et.al. (2004, pp. 29-30)
...
“As lagoas da Reserva Biogenética da Serra da Estrela, estando situadas a altitudes superiores aos  1500m,  podem  ser  classificadas  como  alpinas;  em  consequência  da  sua  localização geográfica estão sujeitas a uma pluviosidade elevada, e a temperaturas relativamente reduzidas, com uma média anual da ordem dos 8/10ºC.” (Costa et.al. (2004, sect. 2.5 Hidrologia, p. 27)




Lagoas do Planalto - da Reserva Biogenética - da Serra da Estrela. (From Costa et. al. 2004)


1. Fontes (engl. springs)


The Serra da Estrela has a large water storage capacity hosting numerous springs with soft and crystal-clear waters. It is no surprise that in these modern times with so much pollution the precious waters from the Serra da Estrela become more and more famous. In the last fifteen years three brands or mineral waters saw the light, and all of them have already national fame.
Most of the springs can be found along the valleys. Tectonic movements probably during the Alpine reactivation produced the so-called Manteigas-Braganca fracture. Along this ample fault several thermal springs can be found . One of them is Caldas de Manteigas in the Serra da Estrela. It is famous for its spa with sulphurous-soda waters that are recommended for the treatment of rheumatism, skin diseases and breathing ailments. It has two springs , the Fonte Quente (43ºC) end Fonte Santa (20ºC).
Near to the mountain summit three majestic peaks are grouped. They are called the Cântaros (English: jars), because they supply water the whole year round. It is in the cirque between the Cântaro Magro, (the slim jar) and the Cântaro Gordo (the fat jar) that the river Zezere finds its offspring. In its catchment area and those of other rivers (Mondego,  Alva, etc.), springs contribute to a major part of their discharge in summer.
Springs host interesting plants and are also excellent biotopes for bryophytes. More than 100 different bryophyte species occur of which about a quarter are included in the red list of the lberian Peninsula.
In large parts of Europe springs are extremely endangered biotopes mainly as a result of draining, fertilization from adjacent areas, and their use as wells. Especially the latter applies to the Estrela. Fortunately many still host important specialized species, although most of the springs are not unspoiled anymore. Here lies an important conservation and restoration task, not only for the Park's authorities and the mineral water factories, but also for the public. (Jan Jansen, 2002, p. 146-47).


Plantas características das fontes na Serra a Estrela são:




Baseado na composição florística e na ecologia J. Jansen (2002) distingue 5 tipos diferentes de vegetação das fontes na Serra da Estrela:


Chrysosplenium springs


In the middle belt the rare Opposite-leaved golden-saxifrage (Chrysosplenium oppositifolium) may form creeping patches in shaded rheocrenes, mostly found on cliffs and slopes. Flushes fed by springs may support similar vegetation at some distance of the origins. Rheocrenes are springs from which the water rushes with high speed such as fountains and cascades. Bryophytes do not fail to grow in these environments and occasionally Wavy bitter-cress (Cardamine flexuosa). Cornish moneywort (Sibthorpia europaea) and perhaps Saxifraga clusii subsp. lepismigena grow there too. The latter is a sticky glandular-hairy Iberian endemic that is less rare in similar conditions in North-Portugal.




Epilobium obscurum springs


Springs with Short-fruited willowherb (Epilobium obscurum) are usually less shaded than Chrysosplenium springs. They mainly occur in the middle, sporadically in the upper belt. Major companions are Blinks (Montia fontana subsp. amporitana) and Bog stitchwort (Stellaria alsine). This kind of vegetation dwells in man-made biotopes, including fountains, wet walls, and gutter streams along the road. Short-fruited willowherb produces stolons with which it can conquer the fissures in the granite walls. Some of the specimens have large petals, reason why the Portuguese taxonomist Sampaio described them as a special variety called Epilobium obscurum var. herminicum.


*
Epilobium obscurum var. herminicum
*
Montia fontana subsp. amporitana







Ranunculus omiophyllus springs




These springs occur occasionally in the middle belt and are predominated by Roundleaved crowfoot (Ranunculus omiophyllus). Small patches grow in muddy seepage areas, often in rills along unpaved roads or in small depressions in wet grasslands. Ivy-leaved crowfoot (Ranunculus hederaceus) occurs in more or less the same kind of biotopes. So far it has not been found in the Estrela. Round-leaved crowfoot is mainly distinguished from the latter by more deeply lobed leaves and larger flowers with petals twice the length of the sepals. Round-leaved crowfoot springs are helocrenes, springs from which the water slowly seeps.


Myosotis springs


Myosotis springs are usually helocrenes too. They are predominated by Pale forget-me-not (Myosotis stolonifera) and a mountain form of Thyme-leaved speedwell (Veronica serpyllifolia ssp. langei). The former is mainly distributed in the higher mountains of the Iberian Peninsula, but can be found in some high mountains in Britain as well. There it also occurs in springs and flushes. Veronica langei is an endemic both from the Estrela and the higher mountains of Spain. It resembles Veronica serpyllifolia subsp. humifusa, a taxon that may occur in some mountains of Central Europe.
Pale forget-me-not vegetation may occur in the middle belt, but in its typical form it is best developed in the highest belt. It can be found near spring-heads and somewhat downstream in slowly Flowing waters. Near bogs, humid Mat-grass swards, and wet heaths it can form mosaics with mats of Ranunculus ololeucos, an amphibian species that seems to prefer deeper waters.




Saxifraga stellaris springs


These springs are usually rheocrenes occurring in the upper belt and characterized by Starry saxifrage (Saxifraga stellaris) Alpine willowherb (Epilobium anagallidifolium), and Festuca rivularis. Angelica major is a frequent companion in this environment, but it also occurs in irrigated hay-meadows and irrigated screes. Only at the end of summer some Saxifraga stellaris springs may lend to dry out. But since they mostly occur in shaded conditions beneath high granitic cliffs, they never seem to dry out totally. In the height of summer the marked colour contrast between the fresh-green of the spring and the dull-green of its surroundings results in a clear pattern. Starry saxifrage and Alpine willow herb are Arctic-Alpine relict species. In Portugal both species are restricted to the springs of the Serra da Estrela. In Europe Starry saxifrage is found in the Arctic and northern Europe and in the mountains of central and southern Europe. The presence of this species and other northern flora elements is related to the cold episodes of the Quaternary when species were driven southwards by the advancing ice-cap. In the Iberian Peninsula this flora encountered the Mediterranean mountain flora, the latter group mainly occupying the xeric biotopes, the northern flora mainly the humid and snow-rich biotopes. Obviously springs have provided excellent refuges. The spring regime of constant temperature permits the northern plants to exist in regions where they do not otherwise occur. The lower summer temperatures in the springs have provided sufficient growth conditions.
St. Patrick's-cabbage (Saxifraga spathularis) may grow around springs but is widely distributed in shaded rock-fissures. It can be distinguished from Starry saxifrage by its larger leaves that are rather leathery, rounded to spoon-shaped, and coarsely toothed. The range of St. Patrick's-cabbage consists of two separate isolated areas, one in the north-western quadrant of the Iberian Peninsula, the other in Ireland.


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Epilobium anagallidifolium
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Saxifraga spathularis



2. Águas correntes - riachos e rios (engl. streams)


From the Serra da Estrela many rivers originate. Together they form an intricate artery system throughout the mountains and the valleys. A unique situation arises in the north-eastern part of the Estrela massif, where the drainage divide of three major catchment basins of Portugal coincide: Tagus, Mondego and Douro. Going clockwise starting in the north the major rivers are Mondego, Zezere. Beijames, Alvoco, Loriga, and Alva. The variation in discharge is mostly related to climatic factors (precipitation, snow-melt). Extremely high discharge peaks are ecological and often socio-economic disasters often caused by human influence. Though climatic change has still not been proved to be induced by man, there is no question that wildfires and extensive felling facilitate a sudden flow of run-off over stripped and bare soils directly to the stream beds. Under natural circumstances erosion would be minimal, skeletal soils would be sparse and an important part of the precipitation would infiltrate the soil or would be retained by vegetation.
Rapidly flowing streams mostly occur in the upper and middle belt. In these environments plants and other organisms must be adapted to stay attached to a finn substrate. In slowly flowing streams silt and other loose materials tend to settle (sedimentation), thus facilitating the establishment of rooted plants. In general there is a shift from rocky, stony river beds at higher altitudes to sandy, silty river beds at lower altitudes.
In the highest parts of the mountain small rivulets and flushes carry a vegetation that is still very much related to springs. However, at some distance slowly running streams may carry patches of Ranunculus oioleucos var. lusitanicus often associated with the dark brown moss Fontinalis antipyretica. These environments contain mostly very soft waters and frequently dry up in summer, reason why their ecology is closely related to that of the temporally inundated biotopes. Fast-flowing
flushes at high altitudes do not contain vascular plants. Only certain bryophytes and lichens are adapted to such conditions.
Going downward, streams contain more water and chances of running dry are getting slim. From about 1,400 m until the foot of the mountain Ranunculus pseudofluitans may develop luxurious fans in relatively fast-flowing streams, often attached to firm substrates like stones. Examples call be seen throughout most of the rivers. Patches may also be found in irrigation channels and leats. Mostly at lower altitudes in still or slower-flowing waters Pond water-crowfoot (Ranunculus peltatus) may be found. Both Crawfoot species often grow together with Water-starwort (Callitriche spp.). A good example of a helophyte is the tussock forming Carex elata subsp. reuteriana, an endemic from NW-Iberia , Montes de Toledo and Sierra Morena. This Sedge species occurs in the middle and lower belt and is occasionally accompanied by Hemlock water-dropwort (Oenanthe crocata), Galium broterianum and Common marsh-bedstraw (Galium palustre). The Carex tussocks collect sediments and form islands in the stream. They often consolidate and strengthen riverbanks, thus preventing erosion. Undisturbed development of these formations may lead to Willow scrub (Salix atrocinerea, Salix salviifolia), under certain conditions preceded by Genista florida scrub, eventually leading to Alder (Alnus glutinosa) or Portugal laurel (Prunus lusitanica) galleries. Downstream, the banks of the river may host species like Water-cress (Rorippa nasturtium-aquaticum), Blue water-speedwell (Veronica anagallis-aquatica), and Veronica Iinkiana. Relatively nutrient-rich streams and channels along roads may contain carpets of Fool's water-cress (Apium nodiflorum), sometimes accompanied by grasses like Creeping bent (Agrostis stolonifera) and Small sweet-grass (Glyceria declinata). At the lower limits of the Park some ditches near villages may yield tall nutrient-demanding species like Yellow iris (Iris pseudacorus). Gypsywort (Lycopus europaeus), Purple-loosestrife (Lythrum salicaria) Common reed (Phragmites australis), and Lesser bulrush (Typha angustifolia), These and other species may become more important in swamps at lower altitudes outside the Park. Here alluvial soils contain more nutrients as a result of the sedimentation of fine material. Alpine figwort (Scrophularia canina) can be found occasionally as a pioneer species in gravel banks along the rivers. During peak discharges large amounts of shingles and pebbles are transported by the river and deposited as gravel banks during phases of lower water levels. These dynamic biotopes are rather similar to screes. (Jan Jansen, 2002, p. 148-49).




3. Águas paradas (engl. standing waters)


For various reasons (increase of waste water, artificial fertilizers, acidification, etc.) nutrient-poor and weakly buffered waters become increasingly rare in large parts of Europe. Fortunately most of the waters in the Serra da Estrela are still nutrient-poor (oligotrophic), only at lower altitudes waters usually become more eutrophicated and polluted, due to both natural accumulation of nutrients and stronger human influence (settlements, agriculture, industry). Vegetation types of oligotrophic waters that are rather common in the Estrela are very rare or sometimes already extinct in other parts of Europe, vegetation of eutrophic standing waters (e.g. floating patches of Duckweed, Lemna spp., helophytic stands of Common spike-rush (Eleocharis palustris) that is common in large parts of Europe is rather rare in Estrela, and therefore left without consideration. Here three types of oligotrophic and mesotrophic standing waters are distinguished.(Jan Jansen, 2002, p. 149).


Characteristic species of these biotopes are:




Note that some of the aforementioned species may also occur in slowly flowing streams. All three ecosystem types have fluctuating water levels. Occasionally they may run dry during a short period, forming transitions to communities of seasonally inundated biotopes.


Stands of Sparganium angustifolium


Floating bur-reed (Sparganium angustifolium) is an Arctic-Alpine relict and within Portugal restricted to the higher parts of the Serra da Estrela. It is a very rare species forming small-sized stands, at shallow sites joined by Antinoria agrostidea. Vegetation dominated by Floating bur-reed may he found at the margin of former glacial lakes in the upper belt. These waters are extremely soft, nutrient-poor and slightly acid. The specimens root mainly in mineral soil, hardly enriched with fine organic material.




Stands of Antinoria agrostidea


The Antinoria stands occur in oligo-to perhaps mesotrophic (in exceptional cases slightly dystrophic) stagnant or slow-flowing waters. The waters are slightly to mode rately acid and their conductivity, a measure for mineral content, is usually low. However there are a few exceptions, induced by excessive road gritting, recently (à volta do ano 2002) constructed concrete gutters along the national road, and local dumps from an open sewer system near the summit.
The plants root in a variety of soils from sand to gravel to peat or organic sludge. They may be joined by species such as Ranunculus ololeucos var. lusitanicum, Bog poudweed (Potamogeton polygonifolius) Bulbous rush (Juncus bulbosus) or Juncus heterophyllus. In peaty situations these vegetation types transgrade into Carex nigra swards, which in turn transgrade into Sphagnum-rich Juncus squarrosus stands.




Stands of Hypericum elodes


These stands sparsely occur in the northern part of the Serra da Estrela. Here Hypericum elodes mainly grows in small pools or locally in irrigated hay-meadows, sometimes joined by the Iberian endemic Baldellia alpestris. In peaty situations they may grow close to Anagallis tenella bogs. Stands of Hypericum elodes are better developed in North-Portugal. For instance in the Serra de Montemuro both species luxuriously mingle with Potamogeton polygonifolius, Juncus heterophyllus, and Antinoria agrostidea, amongst others.




4. Seasonally inundated biotopes


These biotopes consist of flooded areas that dry out seasonally; consequently the vegetation is rich in annuals. The stands are related to therophytic grasslands and sometimes it is difficult to tell one from the other. These short-lived communities host species that are able to complete their life cycle within a very short time, surviving (as seed) unfavourable events such as low temperatures, inundation, ploughing, etc. Many of the species produce seeds that are able to stay dormant during decades, suddenly germinating when conditions become favourable again. Amphibious communities mostly dominated by Bur-marigolds (Bidens spp.) and Water-peppers (Polygonum spp.) occur in relatively nutrient-rich environments. These are rare in Estrela but elsewhere generally common and therefore left without consideration. Amphibious communities from oligotrophic biotopes are of particular interest within the 15 member states of the European Union. This type of vegetation usually occupies small areas (often less than a square meter), occurring on bare soils or in gaps of vegetation that mostly originate from disturbance. (Jan Jansen, 2002, p.150)


Na Serra da Estrela as seguintes espécies características  ocorrem:






Aos biótopes que são sazonalmente inundades pertencem os ‘charcos temporários’. Estes biótopes têm interesse especial na conservação por causa da sua vulnerabilidade. Um trabalho existente em Portugal sobre a vegetação dos charcos temporários (mediterrânicos)  (Habitat 3170) de Portugal é o trabalho de Vasco Manuel Almeida de Silva sobre: “A vegetação dos Charcos e Cursos de Águas temporárias. Estudo da Ordem Isoetetalia em Portugal.”.

Dentro da formações de biótopos sazonalmente inundadas da Serra da Estrela Jan Jansen (2002) distingue quatra assembleias:


4.1 Dwarfish community with Cicendia filiformis


This rare miniature community is characterized by the presence of Yellow centaury (Cicendia filiformis), a tiny yellow-flowering member of the Gentiane family. Dwarf rush (Juncus capitatus) is one of its companions. The temporally inundated micro stands with Cicendia occur in both the lower and middle belt and are examples of "warp-and-woof" communities. They mainly consist of dwarf plants occupying microsites (the warp) within taller formations (the woof). The micro-stands develop in early spring in open grasslands (pastures, meadows). In the course of the season the grasslands become more dense and (depending on the altitude and the fluctuation of the climate) by the end of spring or the beginning of summer the micro-stands die off and are hardly recognizable anymore.




4.2 IIlecebrum community


Characteristic species are Coral necklace (Illecebrum verticillatum), Trailing St.  John's-wort (Hypericum humifusum), and Water-purselane (Lythrurn portula). These are frequently accompanied by Dwarfish species (Juncus capitatus, Juncus bufonius, Juncus tenageia subsp. tenageia) and Spurrey species (Spergularia capillacea, Spergularia rubra). Stands occur from the lower to the middle belt around the edges of pools, rivers, shallow ditches, gravel pits, rye-fields, footpaths, car tracks, drove-roads, etc. Periodical inundation or percolation at low water levels during a considerable part of the rainy season is assumed. The water mostly originates from direct precipitation water or indirectly from run-off, more rarely from seepage. Mostly standing waters are concerned, but sometimes slowly running (on gently sloped sites).




4.3 Holcus gayanus-Bryum alpinum carpets


 
Holco-Bryetum Comunidade na Serra da Estrela (From Jan Jansen, 2011) 


These carpets are inhabited by various species and may appear as miniature gardens. The vegetation consists of a perennial moss layer of Bryum alpinum in which tiny annuals and bulbous plants occur such as the characteristic Holcus gayanus, a northwest Iberian endemic annual grass species. Bryum alpinum is rather common in the Serra da Estrela, especially in the cirques and the higher parts of the glacial valleys. There it thrives extremely well in intermittent, slowly percolating flows on warm gently sloped granitic rocks, polished by the ancient glaciers. The preponderant rocky environment functions as a storage heater. It affects the microclimate of the moss carpets by direct thermal conduction and by the radiation of collected solar heat. Temperature extremes are pronounced on rocky surfaces, but as long as the moss carpets are soaked, temperature fluctuations stay relatively attenuated. However in July dry moss carpets may be easily heated more than twice the surrounding atmosphere. The vascular plants in the perennial Bryum carpets have a typical southern growth rhythm. Some annuals can be observed already in early winter. In early spring the aspect is formed by the flowered specimens of Narcissus and Crocus. However most species have a late vernal or early aestival maximum, depending on the weather conditions. Then the green to reddish-brown moss layer of Bryum alpinum is often covered by it blond-coloured blanket of Holcus gayanus. Merendera montana is the last species to flower (mid to late summer). From October to July there is a chance of freezing. In winter Bryum carpets lit by the sun may thaw
during the day, while shaded carpets may stay frozen. Melt water influence declines in the course of spring, admitting an increasing influence of rain water. It is then that temperatures of the Bryum carpets rise and the vascular plants start to come out, most of them reaching their maximal development from late spring to early summer. For some species the temporally irrigated carpets function as sanctuaries against wildfires. The stands occupy more or less natural habitats and often host a large number of Iberian endemics, such as Sedum maireanum and Scilla ramburei subsp. beirana. The miniature carpets are very well-developed in the Serra da Estrela, but they can also be seen in the Serra da Gardunha, Serra do Geres and Montesinho.


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Bryum alpinum
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Holcus gayanus
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4.4 Juncus perpusillus populations


Juncus tenageia subsp. perpusiilus is a tiny Iberian endemic dwarfrush, related to Sand rush (Juncus tenageia subsp. tenageia). Populations usually form small patches in seasonally inundated hollows (Portuguese: charcos, pocas) in Mat-grass swards, which are subjected to summer grazing. The patches are well developed in summer. when the hollows run dry. Within Portugal this biotope is restricted to the upper belt of the Serra da Estrela. Spergularia rubra subsp. capiIlacea, a species indicative for trampled areas, is often present.




Charco numa turfeira de transição no Planalto da Serra da Estrela


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Spergularia rubra subsp. capiIlacea


Outras fotos de plantas da “turfeira” no Planalto da Serra da Estrela:




Gentiana pneumonanthe




Carex nigra subs. iberica




Pedicularis sylvatica subsp. sylvatica




Carex echinata




Potentilla herminii na turfeira de Sphagnum




Potentilla herminii




Folhas de Pontentilla herminii




Carex nigra subsp. iberica (esquerda e centro) e Carex echinata (cima esquerda) na turfeira de Sphagnum


Plantas na margem da “turfeira” e da Estrada Nacional no Planalto da Serra da Estrela:



Ranunculus spec.




?Polygonum arenastrum




Spergularia rubra subsp. ?capillacea




Spergularia rubra subsp. ?capillacea




?Arenaria montana


5. Turfeiras (engl. bogs)
As turfeira altas (habitat 7140pt1) da Serra da Estrela estão incluidas na lista de habitats do Plano Sectorial da Rede Natura 2000, por isso confere um estatuto especial à este habitat para a sua conservação e protecção.


São caracterizadas da seguinte forma na descrição do habitat 7140:


Turfeiras oligrotróficas, com cobertura de neve durante até 6 meses por ano, alimentadas por águas frias (mesmo durante o Verão), sem deficit de água durante todo o ano devido às águas provenientes do degelo.
• Nestas turfeiras a cobertura de Sphagnum excede largamente a das plantas vasculares, característica que tem sido utilizada como indicação de ombrotrofia.
• Caracterizam-se pela ocorrência de uma grande diversidade de espécies de Sphagnum, juntamente com Carex nigra e Drosera rotundifolia, ou Juncus squarrosus e Sphagnum compactum. Tratam-se, em ambos os casos, de comunidades permanentes, sendo a distância ao nível freático maior no caso das comunidades com Juncus squarrosus. As comunidades com Carex nigra incluem áreas inundadas, colonizadas por Sphagnum cuspidatum e S. auriculatum s.l., bem como formações contínuas em que dominam S. flexuosum, S. capillifolium var. tenellum e S. tenellum. As formações com Juncus squarrosus são também contínuas e, nalguns casos, sobretudo acima dos 1800 metros de altitude, podem ter uma extensão considerável e preencher, quer pequenas elevações, quer pequenas depressões, sem qualquer descontinuidade.
• Catenalmente, estas comunidades turfosas contactam com os urzais higrófilos com Calluna vulgaris ou directamente com cervunais (habitat 6230) ou versões mesófílas dos zimbrais de Juniperus communis subsp. pl. (habitat 4060). Os contactos catenais com as comunidades de águas livres dão-se com formações de Ranunculus ololeucus e comunidades de Sparganium angustifolium (habitat 3130).



Bogs are ombrotrophic formations (= largely depending on atmospheric water). They are mainly composed of peat mosses (Sphagnum spp.) and often joined by sedges (Carex spp.), and some times by rushes (Juncus spp.), a few forbs, and dwarfshrubs.
A peat moss keeps on growing in its top, while at the bottom it dies from lack of light and starts to decay. Its top is just a few centimetres above the water table, while the rest retains large amounts of water. Under favourable conditions peat mosses may increase a few centimetres up to almost half a meter per year. A large amount of peat mosses may actively raise the water table. Thus creating a bog formation.
The cell walls of peat mosses function as ion exchangers. They absorb cations from rain, run-off or blown-in particles and in exchange release hydrogen ions turning the water very acid. However they bind much more nutrients than the plants need for their survival. In this way peat mosses create and maintain a nutrient-poor, acidic environment that stimulates their own growth but is intolerable to all but a small number of highly specialized plant species.
The property of bogs to conserve organic rests (pollen, leaves, roots, etc.) adds to their scientific interest. It is possible to trace the vegetation history and related climate by studying the deposits. These are well-conserved in the acidic bog layers, which actually function as natural archives.
The Estrela has a dry period in summer and consequently bogs are mostly small-sized, occurring in depressions, water margins, and seepage areas. However, most known peat moss species from Portugal do occur and some of them are restricted to the Estrela .
In the Estrela only very small parts of bogs may be influenced by precipitation only. Most of them are also fed by run-off water, which contains more minerals thus facilitating the growth of less specialized species. (Jan Jansen, 2002, p. 151-52).


Espécies mais ou menos características são:




Bogs are vulnerable and in the Estrela they are endangered. Of course the dry summers lire limiting but the main cause of deterioration is pollution. There is uncontrolled rubbish dump. Some visitors leave rubbish after a picknick in the summer season (e.g. frequently at Covao do Boi). In winter "ski-tourists" use plastics for sliding and leave them being prey for the winds. After months, even years they can be found scattered for miles around, blocking rivulets and choking bogs. However, not only visitors can he blamed. At the top of the mountain an open sewer system of the shopping centre discharges into an oligotrophic rivulet and reaches some extremely sensitive bogs. Some of the concrete gutters along the roads discharge in bogs and nutrient-poor waters.


Jan Jansen (2002) limita-se a distinguir 3 associações diferentes de turfeiras na Serra da Estrela - devido à falta de espaço no guia que escreveu. Uma descrição e classificação exhaustiva das turfeiras da Serra da Estrela seria um estudo urgente a fazer devido à vulnerabilidade e raridade destes biótopes em Portugal. Por mais, além do turismo do Inverno no Planalto da serra onde ocorrem a maioria das turfeiras, parece de haver também mudanças no pastoreio. Recentemente (2013) foi observado pastagem por bovídeos nas turfeiras do planalto da serra. É natural que o peso e os excrementos destes animais proporcionam outros (e talvez novos) impactos sobre as turfeiras do que os do gado de ovelhas e cabras que fazem deste há séculos parte do sistema destas turfeiras.


5.1 Juncus squarrosus-Sphagnum bogs


These are the most common type of bogs and occur in the upper belt. They consist of Sphagnum hummocks in which Heath rush (Juncus squarrosus) most frequently grows, often joined by species such as Star sedge (Carex echinata), Round-leaved sundew (Drosera rotundifolia), and Bog violet (Viola palustris), Drosera is one of the most specialized plants. This perennial herb is notable for its insectivorous habit. Its leaves are covered with long gland-tipped hairs that are irritable and mobile, entrapping and digesting insects. The use of this alternative nutrient source is an excellent adaptation to the nutrient-poor bog environment. The less the bogs are influenced by run-off the more competitive Drosera becomes. At the margins of the bogs Drosera is replaced by other species that profit from the mineral-rich soil. For instance in less peaty but still hygromorphic organic soils the appearance of Marsh gentian (Gentiana pneumonanthe) and Common lousewort (Pedicularis sylvatica subsp. sylvatica) show the transition to humid Mat-grass swards. Juncus squarrosus-Sphagnum bogs are mostly found along small ponds and glacial lakes, but they may also form complex mosaics with wet heaths. In these situations the rare Bilberry (Vaccinium myrtillus) may show up .


(Associação: Junco squarrosi-Sphagnetum compacti Braun-Blanquet. P. Silva. Rozeira & Fontes 1952 da classe Oxicocco-Sphagnetea Br.-Bl. & Tüxen ex Westhoff, Dijk & Passchier 1946)




As Sphagnum  espécies [3] da classe Oxicocco-Sphagnetea da Serra da Estrela são:




5.2 Carex (nigra subsp.) iberica bog


Swards of an Iberian subspecies of the Common sedge (Carex nigra subsp. iberica) prefer rather muddy soils and occur mostly in channels adjacent to the slightly raised Sphagnum carpets. They are mostly species-poor and occur in the upper belt. Some good examples can be observed near Fonte dos Perús, Covão do Boi, and Covão do Cimeiro.


Correspondência fitossociológica: Complexos de vegetação com comunidades da ordem Caricetalia nigrae (classe Scheuchzerio-Caricetea nigrae) e da aliança Ericion tetralicis p.p. (classe Oxycocco-Sphagnetea).




 
Carex nigra subsp. iberica


5.3 Anagallis tenella bog


In the middle belt small Sphagnum-rich vegetation patches may occasionally occur in irrigated meadows or near seepage areas. These patches develop under stagnating water conditions causing accumulation of peat. The vegetation includes some species that never seem to reach the upper belt such as Bog pimpernel (Anagallis tenella), Arnica montana subsp. atlantica, Common yellow sedge (Carex demissa), Lesser spearwort (Ranunculus flammula), and Marsh speedwell (Veronica scutellata). These species often intermingle with elements from humid Mat-grass swards and nutrient-poor wet meadows.


Anagallis tenella
Arnica montana subsp. atlantica
Carex demissa
Ranunculus flammula
Veronica scutellata





Anexos


1 Bau und Lebensweise der Sphagnen und ihre Bedeutung für das Hochmoor


Um Entstehung und Haushalt der Hochmoore zu verstehen, muß man sich gründlich mit den Massen-Torfbildnern und damit Schlüsselarten vertraut machen, den Torfoder Bleichmoosen, der Gattung Sphagnum. Ein Bestand von Sphagnum-Pflanzen stellt ein schwammartiges Kapillarsystem dar (s. Lehrbücher der Systematischen Botanik), das nach einer Trockenperiode von Luft, nach Regen aber von Wasser erfüllt ist. Die „Moosblättchen" bestehen zum überwiegenden Teil aus abgestorbenen, oft spiralig versteiften und sogar mit groben Poren versehenen Zellen, Hyalozyten, mit Wasserspeicherfunktion, zwischen denen, volumenmäßig zurücktretend, assimilierende Chlorozyten liegen. Die „Stämmchen" sind von einem Zylinder toter Speicherzellen umkleidet. Kapillarräume entstehen auch zwischen den meist hohlen „Blättchen" und ihrem „Ast" sowie zwischen den polstrig-gedrängt wachsenden ganzen Pflanzen. Die daraus resultierende Wasserspeicherkapazität ist artspezifisch und beträgt für S. magellanicum (= S. medium) das 21-25fache des Trockengewichts, für S. recurvum das 14-18fache (rund 20 bzw. 10g/100 ccm, s. OVERBECK 1975).
Eine Regulationsmöglichkeit der Wasserabgabe besteht bei diesen Thallophyten natürlich nicht. Da die Evaporation in Hochmooren an warmen Strahlungstagen etwa der in Trockenrasen entspricht (FARBAS 1931), ist es verständlich, daß Hochmoore an relativ niederschlagsreiche und evaporationsschwache Gebiete gebunden sind (s. u.).
– Die „Schwammstruktur" einerseits und die Dichte infolge stärkerer Zersetzung andererseits bewirken, daß Sphagnum-Rasen und aus ihnen entstandener Torf wenig wasserdurchlässig und damit wenig durchsickerbar sind; der mooreigene Grundwasserspiegel kann daher kleinflächig wechseln.
Die anhaltende Durchtränkung bewirkt Luftabschluß der tieferen Schichten und entsprechende Sauerstoffarmut. Unter anaeroben Verhältnissen wird zunächst die ohnehin nur geringe Eiweißmenge abgebaut; Gasblasen aus Methan, die beim Tritt in Schlenken aufsteigen, und der Geruch nach H 2S machen dies sinnfällig. Tiefwurzler können hier nicht existieren. Die Abnahme an Sauerstoff und die relative Anreicherung an Kohlenstoff und Wasserstoff stellen das erste Stadium der Inkohlung dar; Torflager, wenn auch nicht aus Sphagnen, sondern überwiegend aus Kormophyten aufgebaut, waren Voraussetzung für die Bildung von Braun- und später Steinkohle unter Druck über Jahrmillionen hin. Im Torf erhalten sich nicht nur bekanntlich schwer zersetzliche Polymere wie Lignin (und damit Holz) und Sporopollenin (und damit das äußere Sporoderm, Exospor, Exine) von Farnsporen und Pollenkörnern, sondern in geringerem Maße auch Zellulose. Die Zellwände der Sphagnen sind übrigens schwerer zersetzbar, als es reinen Zellulose-Pektin-Wänden entsprechen würde. So lassen sich die Sphagnum-Arten, die den jeweiligen Torf gebildet haben, bei geringeren Zersetzungsgraden nach dem Zeltnetz identifizieren. Moore sind daher die besten „Archive" der nacheiszeitlichen Vegetationsgeschichte.
Daß die Bleichmoose gerade für den extrem nährstoffarmen Standort Hochmoor so geeignet sind, beruht ferner auf einer weiteren Eigenart im Chemismus ihrer Zellwände: Infolge eines hohen Anteils an Polyuronsäuren wirken die Wände als Kationenaustauscher. Man wird sie als „Nährstoff-Fangorgan" und damit als ökologische Anpassung werten dürfen. Kationen, die mit Staub und Niederschlägen auf das Moor gelangen, werden rasch gegen Protonen eingetauscht, welche ihrerseits das Substrat ansäuern; dabei stellt sich ein physikalisch bestimmtes Gleichgewicht zwischen Lösung und Zellwand ein. Die Pflanze kann diese locker gebundenen basischen Kationen allmählich gegen eigene Protonen eintauschen und aktiv, entgegen der Konzentrationsgefälle, aufnehmen. Dabei wird der „Austauscher regeneriert". Der Kationengehalt des von Moosen abgepreßten Wassers kann daher stark schwanken und vom „Standortswasser" abweichen. Die Azidität des Hochmoores bleibt hoch; pHWerte von 3-4 sind normal.
Das Wachstum der Sphagnen ist dank dieser Anpassungen erstaunlich groß: Der Längenzuwachs ist artspezifisch verschieden und kann von wenigen cm (bei den bultbildenden Sphagnen wie S. medium) bis zu etwa 50 cm/Jahr in Schlenken reichen (s. dazu DIERSSEN & DIERSSEN 1984). Solche locker und gut durchlichtet wachsenden Schlenkenpflanzen (z. B. S. recurvum) sinken auf die Seite und schieben sich so über seitliche Konkurrenten. Das Wachstum einer Hochmooroberfläche kann man auf jährlich 2-10 cm schätzen. Da die toten Pflanzenteile später zusammengepreßt werden, sind freilich für die Bildung von 1 cm Torf größenordnungsmäßig 10-20 Jahre anzusetzen (z. B. CASPARIE 1969, mit Radiokarbondatierung). Diese positive Stoffbilanz wird nach Entwässerung infolge von Torfzersetzung bei Durchlüftung negativ.











2 Tabelas fitossociológicas


Uma tabela sinóptica da vegetação das Classe Littorelletea da Serra da Estrela encontra-se em Jan Jansen (2011):  Managing Natura 2000 in a changing world: - Radboud Universiteit - Anexos -  (Chapter 6, Table 1 … Destacado em amarelo: Lichens e Musgos - alteração da tabela original).



Chapter 6, Table 1 Littorelletea in the Serra da Estrela


Uma tabela sinóptica da vegetação das Classe Isoëto-Nanojuncetea da Serra da Estrela encontra-se em Jan Jansen (2011):  Managing Natura 2000 in a changing world: - Radboud Universiteit - Anexos -  (Chapter 6, Table 2 … Destacado em amarelo: Lichens e Musgos - alteração da tabela original).



Chapter 6, Table 2 Isoëto-Nanojuncetea in the Serra da Estrela





3 Associações fitossociológicas


(As associações fitossociológicas presentes em ambientes aquáticos da Serra da Estrela foram identificadas por: Jan Jansen (2002):Geobotanical guide of the Serra da Estrela. Instituto da Conservação da Natureza. Ministério das Cidades, Ordenamento do Território e Ambiente, Lisboa.
As descrições das classes fitossociógicas são as descrições das respectivas classes fitossóciológicas em: Rivas-Martínez et. al. (2002): Vascular Plant Communities of Spain and Portugal. Addenda to the Syntaxonomical Checklist of 2001. ITINERA GEOBOTANICA. Vol. 15(1).)




FLOATING OR ROOTED SUBMERGED AQUATIC VEGETATION
Ia. FRESH-WATER VEGETATION
*
Classe LEMNETEA: Bryo-cormophyte fresh-water floating communities (Lemnetalia) [small to medium acropleustophytes (Lemnion minoris), mesopleustophytes of lemnids and riccielids (Lemnion trisulcae) or hydrocharids (Lemno-Hydrocharition morsus-ranae)]. Cosmopolitan.

*
Classe POTAMETEA: Aquatic fresh water macrophyte communities. Rooted hydrophytes (Potametalia) [fresh water elodeids (Potamion), brackish water elodeids (Zannichellion pedicellatae), batrachids of running water (Ranunculion fluitantis), batrachids of standing water (Ranunculion aquatilis) and nymphaeids (Nymphaeion albae)]; non rooted nutrient-rich hydrophytes (Utricularietalia) [floating utricularids (Utricularion) and ceratophyllids (Ceratophyllion demersi)]. Cosmopolitan.

AMPHIBIOUS VEGETATION OF FRESH-WATERS, SPRINGS AND FENS

IIa. PIONEER EPHEMERAL VEGETATION
*
Classe BIDENTETEA TRIPARTITAE: Pioneer annual on periodically flooded nutrient rich pools, lake margins and riparian nitrophilous communities (Bidentetalia tripartitae) [damp high disturbed (Bidention tripartitae), desiccate riparian clayey (Chenopodion rubri)]. Holarctic.

*

Classe ISOETO-NANOJUNCETEA: Pioneer annual and dwarf perennial ephemeral isoetid communities on periodically  flooded bare soils. Spring and early summer bloom sometimes with isoetids (Isoetetalia) [ephemeral graminoid slightly inundated (Agrostion pourretii), dwarf pioneer Mediterranean drainage basin (Isoetion), dwarf pioneer Mediterranean-Atlantic (Cicendion), long flooded tall therophytes (Menthion cervinae)]; late summer and autumn bloom without isoetids (Nanocyperetalia) [dwarf oligohaline water (Verbenion supinae), calcareous or loamy nutrient-rich water (Lythrion tribracteati)]. Holarctic.

IIb. VEGETATION OF LAKES, SPRINGS, FENS AND BOGS
*
Classe ISOETO-LITTORELLETEA: Dwarf helophyte amphibious oligotrophic communities on shore dystrophic lakes, nutrient-poor standing or slow-flowing waters (Littorelletalia) [amphibious nutrient-poor deep standing water (Littorellion uniflorae), Atlantic and Mediterranean West Iberian shallow meso-oligotrophic waters (Hyperico elodis-Sparganion), continental fluctuating water on loamy soils (Eleocharition acicularis)]. Holarctic.

*
Classe MONTIO-CARDAMINETEA: Cold spring communities dominated by bryophytes and evergreen soft helophyte phanerogams (Montio-Cardaminetalia) [oro- and cryorotemperate cold springs of base-poor water (Cardamino-Montion), meso- and supratemperate mostly phanerogams in soft running water (Caricion remotae), calcareous springs dominated by bryophytes (Palustriellion commutatae), Oroiberian Carpetan-Leonese and Western Orocantabric oligotrophic cold springs (Myosotidion stoloniferae), muddy slow flowing cold springs dominated by rooted stoloniferous helophyte ranunculids (Ranunculion omiophyllo-hederacei)]. Holarctic.

*
Classe OXYCOCCO-SPHAGNETEA: Blanket bogs and peaty ombrogenous or aquatic Sphagnum and heath communities (Erico tetralicis-Sphagnetalia papillosi) [hyperoceanic mostly ombrotrophic Cantabrian-Atlantic (Erico mackaianae-Sphagnion papillosi), cold oceanic and drying resistent wet peat heaths wide Atlantic (Ericion tetralicis)]. Cosmopolitan.

*
Classe PHRAGMITO-MAGNOCARICETEA: Swampy, fenny, lacustrine and riverine helophyte communities (helostadion) dominated by perennial graminoids, sedges, forbs and herbs of fresh and brackish waters. Tall fresh water graminoids (Phragmitetalia) [only one alliance (Phragmition australis: Phragmitenion australis  tall graminoid fragile to drainer periods, Bolboschoenenion maritimi  medium tall graminoid resistent to desiccation characterized by Bolboschoenus maritimus subsp. maritimus and Scirpus triqueter)]; tall fresh water sedges (Magnocaricetalia) [swamps, lakes and riversides, Eurosiberian and Mediterranean (Magnocaricion elatae), riverine Mediterranean West Iberian (Caricion reuterianae), Madeiran (Deschampsion argenteae)]; pioneer short rhizomatous herbs and graminoids of fresh water streams and pools with changeable water level (Nasturtio-Glycerietalia) [tall stiff graminoid (Glycerio-Sparganion: Glycerio-Sparganienion  deep water level, with only occasional desiccation, Glycerienion fluitantis  pools and slow flowing shallow waters with desiccation periods, Phalaridenion arundinaceae  streams with long drainer periods characterized by Phalaris arundinacea mostly in rich soils and Oenanthe croccata in poor soils), limp prostrate in nutrientrich waters (Rorippion nasturtii-aquatici)]; sedges and graminoids in brackish water (Bolboschoenetalia compacti: Bolboschoenion compacti). Cosmopolitan, but absent in polar and related very cold bioclimates.

*
Classe SCHEUCHZERIO-CARICETEA FUSCAE: Mire, fen and bog communities of small sedges and bryophytes of Holarctic cold territories. Pioneer in oligo-dystrophic peat moss (Scheuchzerietalia palustris: Rhynchosporion albae), oligotrophic peats and mineral peaty soils (Caricetalia nigrae) [supra and orotemperate and related mountain climates (Caricion nigrae), oro and cryoromediterranean Nevadensian (Festucion frigidae), Atlantic thermo and mesotemperate and related oceanic climates (Anagallido-Juncion bulbosi)]; fens, calcareous oligo-mesotrophic peats and peaty flushed soils (Caricetalia davallianae) [Eurosiberian and Mediterranean mostly at high altitudes
(Caricion davallianae), pioneer basophilous Arctic and Alpine (Caricion maritimae)]. Holarctic.



Associações fitossociológicas presentes nos ambientes aquáticos da Serra da Estrela (From Jan Jansen (2002)


[1] Jansen, J. 2002. Geobotanical guide of the Serra da Estrela. Instituto da Conservação da Natureza. Ministério das Cidades, Ordenamento do Território e Ambiente, Lisboa.
[2] Costa, L.T., Fidalgo  J.P., Neves R. & Rufino R. 2004.  Lagoas do Planalto Superior da Serra da Estrela.

Instituto  da  Conservação  da  Natureza  /  Centro  de  Zonas  Húmidas.
[3] Moss Families of Britain & Bildatlas Moose Deutschlands
[4] Otti Willmanns. 1973.1998. Oekologische Pflanzensoziologie. Quelle & Meyer. Wiesbaden (p.256-257).

[5]  Descrições das classes fitossociógicas: Rivas-Martínez et. al. (2002): Vascular Plant Communities of Spain and Portugal. Addenda to the Syntaxonomical Checklist of 2001. ITINERA GEOBOTANICA. Vol. 15(1).
(Download link para: Volume I e Volume II)







Veja à seguir: 13. The Northern Serras of Portugal (Serra da Estrela  - Ambientes rochosos)




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