Northern Andean Páramo (general)

Although páramo is generally described as high-altitude, wet tropical grassland above the tree line in the Andes of Venezuela, Colombia, Ecuador and northern Peru, it is extremely rich in biodiversity and contains a high level of endemism. One of the most distinctive features is the giant rosette of the Espeletia endemic complex. This includes over 100 species that belong to the sunflower family (Asteraceae). These plants are found only at high elevations of the northern Andes Mountains of Venezuela, Colombia and Ecuador. The centre of diversity is the Venezuelan Andes, while the eastern cordillera of Colombia also has a large number of species. The range of the complex extends from the coastal Caribbean mountains of Venezuela, north along the Sierra de Perijá to the Sierra Nevada de Santa Marta of Colombia, and south into northern Ecuador. The southernmost extent of the range is a disjunct population in an isolated páramo of central Ecuador known as the Serranía de Llanganates. Originally these were all classed as members of the genus Espeletia but this was elevated to a sub tribe, the Espeletiinae, and the species separated into eight separate genera, including Espeletia, Coespeletia, Espeletiopsis, Ruilopezia, Libanothamnus, Tamania, Carramboa and Paramiflos. Recent molecular studies, however, suggest that at least some of these genera may not be natural (monophyletic) groups. Many are characterized by an unbranched stem, often covered in a thick layer of dead leaves, topped by a rosette of spirally arranged, wooly leaves. Unlike most plants in the páramo, which tend to be short grasses, small herbs and shrubs, the giant rosettes of the Espeletia complex can grow to 5 meters tall and live for more than 100 years. Many of the morphological and physiological traits are thought to be adaptations to the harsh tropical montane climate. The spiral arrangement leaves and their dense layer of hairs together with the retained dead leaves help to provide both thermal insulation and protection against UV radiation. Of considerable interest, however, is the fact that the giant rosette growth form has evolved independently in plants from a variety of similar habitats across the world, with Espeletias being comparable with the silverswords of Hawaii and giant senecios and lobelias of Africa. This provides compelling evidence that this growth form is an adaptation to tropical montane conditions. In addition to the giant rosette, the evolutionary radiation of the Espeletia complex has resulted in a remarkable diversity of morphological forms, ecological specializations and life history traits. Species are found from the montane forests at about 2800 m, to the edge of the glaciers at 4600 m, and have adapted to a wide range of environmental conditions, from steep talus slopes and xeric rock outcrops, to wet marshes and bogs. Growth forms range from tiny, mat-forming sessile rosettes less than 5 cm tall, to giant rosettes, to branched shrubs and even large trees over 15 m tall.

Northern Andean Shrub Páramo

Shrub dominated páramo occurs at altitudes ranging from about 3000-4000 m. However, species composition is extremely variable depending on factors such as geographical position, altitude, humidity, land form and soil type. In the Colombian Cordillera Orientale the characteristic plant families are Asteraceae, Ericaceae and Melastomataceae. The most characteristic shrub genus is the endemic Bacquetia (family?), which includes species such as Bacquetia glutinosa and B. vernicosa. Other characteristic shrubs include the endemic Eupatoria (Ageratina) tinifolium (Asteraceae) and Purpurella grossa (family?), but of particular interest are members of the endemic genus Espeletiopsis (Asteraceae) such as Espeletiopsis corymbosa, E. garciae, E, jimenez-quesadae, E. miska and E. pleiochasia. These species usually occur on steep slopes with moderately acid soils. Other associated species include the endemic Clethra fimbriata (Clethraceae) and Gaultheria rigida (Ericaceae). On well-drained slopes, the endemic or near endemic shrub Senecio vaccinioides (Asteraceae) may predominate. In the more humid areas the ground layer beneath these Senecio stands are often dominated by bryophytes such as Pleurozium schreberi and Thuidium peruvianum. In other places, particularly in the more humid zones, such as around the headwaters of the Rio Casanare, well developed stands of the endemic Eupatoria tinifolia (Asteraceae) occur. Here the associates include various endemic species such as Baccharis prunifolia (Asteraceae), Escallonia myrtilloides (Escalloniaceae), Hypericum laricifolium (Hypericaceae), Miconia salicifolia (Melastomataceae) and Vallea stipularis (Elaeocarpaceae).

Northern Andean Dwarf Shrub Páramo

Ranging in altitude from about 3000-3800 m this vegetation is mostly characterized by the bryophyllous rubiaceous dwarfshrub Arcytophyllum nitidum. If undisturbed it can reach about 1.2 m in height and have a percentage ground cover up to 80%. Locally, however, other woody species, such as the endemic Lobelia tenera (Campanulaceae) and Sporobolus lasiophyllus (Poaceae) can make a significant contribution to ground cover, while less common species include the endemic Castratella piloselloides (Melastomataceae) and Paepalanthus paramensis (Eriocaulaceae). Structurally the vegetation can be divided into two tiers: a dwarf shrub layer, and a herb-graminoid layer mainly dominated by bryophytes. Typical herb layer species include the endemic Oreobolus obtusangulus subsp. rubrovaginatus (Cyperaceae) and Rhynchospora paramorum (Cyperaceae). Among the many other accompanying species are the endemic Geranium multiceps (Geraniaceae), and several other endemic taxa such as Epidendrum chioneum (Orchidaceae), Lourteigia (Eupatorium) microphylla (Asteraceae), Masdevallia coriacea (Orchidaceae) and Spiranthes vaginata (Orchidaceae) reach their maximum extent within the dwarf shrub zone.

Northern Andean Bamboo Páramo

Páramo dominated by the endemic bamboo Swallenchloa tesselata (Poaceae) is confined to a relatively narrow belt in the more humid zones. In the Colombian Cordillera Orientale, it ranges in altitude from about 3300-4150 m. The common associates include various endemic taxa such as Calamagrostis effusa (Poaceae), Carex pichinchensis (Cyperaceae), Hypericum lancioides (Hypericaceae), Oritrophium peruvianum (Asteraceae), and several species of the curious endemic genus Espeletia (Asteraceae). In some of the more boggy areas, such as on sloping valley floors Swallenochloa can also be found in association with peat mosses such as Breutelia allionii and Sphagnum magellanicum. Here various herbs occur such as the endemic Eriocaulon microcephalum (Eriocaulaceae), Lachemilla nivalis (Rosaceae), Luzula gigantea (Juncaceae), Niphogeton lingula (Apiaceae), Valeriana plantaginea (Valerianaceae) and a variety of Espeletia species including E. grandiflora, E. incana, E. lopezii, E. murilloi and E. summapacis. The peat in these zones has been dated at up to 5000 years old. On relatively steep slopes species such as the endemic Eryngium humile (Apiaceae) become more conspicuous together with further espeletias such as E. annemariana, E. curialensis, E. cleefii and E. discoidea. In the better-drained areas another suite of species may be encountered. Here the endemic bunchgrass Calamogrostis effusa (Poaceae) may become co dominant with or even dominant over Swallenchloa. The associated flora is again dominated by endemic taxa such as Calamagrostis bogotensis (Poaceae), Castratella piloselloides (Melastomataceae), Paepalanthus andicola (Eriocaulaceae), Sisyrinchium pusillum (Iridaceae) and various espeletias like E. congestiflorus (Asteraceae).

Northern Andean Bunchgrass Páramo

Páramo characterized by bunches or tussocks of the endemic grass Calamagrostis effusus (Poaceae) ranges in altitude from about 2900-4500 m on moderately acid soil and where foggy conditions often prevail. It generally includes a scattering of stem rosettes of the endemic genera Espeletia and Espeletiopsis (Asteraceae). In fact, several species such as Espeletia barclayana, E. brachyaxiantha, E. jaramilloi and Espeletiopsis corybosa, E. guacharaca, E. muiska and E. colombiana are more or less restricted to bunchgrass páramo. Other common species may include the endemic Castratella piloselloides, C. rosea (Melastomataceae), Cortaderia sericantha (Poaceae), Gnaphalium antennarioides, Hieracium avilae (Asteraceae) and Lobelia tenera (Lobeliaceae), many of which are sessile rosettes or tufted species. At the highest parts of this zone (3900-4500 m) Calamagrostis effusus can attain ground cover percentages of over 50%. Here the common stem rosette species are Espeletia lopezii, E. cleefii, E. azucarina and Espeletiopsis colombiana, E. guacharaco and E. santanderensis, and they are typically accompanied by the endemic dwarf shrubs like Diplostephium colombianum (Asteraceae) and Loricaria complanata (Asteraceae).

Northern Andean Super Páramo

The super páramo is the highest vegetation belt of the tropical northern Andes ranging in altitude from about 3500-4800 m. The zone includes a rich collection of endemic vascular plants. For example, there is a particularly diverse assemblage of endemic species of Senecio (Asteraceae). Many of these, such as the herbaceous Senecio cocuyanus, S. adglacialis, S. supremus, S. pasqui-andinus and the shrubby S. cleefii and S. guicanensis can be found in the Sierra Nevada del Cocuy, but several species are confined to a single summit or range. Senecio santanderensis, for example, is only known from the Páramo de Santurbán and the Páramo de Almorzadero. Other endemic species have their distributions centred on certain areas. Cerastium imbricatum (Caryophyllaceae), Diplostephium rupestris (Asteraceae), Geranium multiparitum (Geraniaceae), Ourisia muscosa (Plantaginaceae), Rumex tolimensis (Polygonaceae) and Werneria humilis (Asteraceae), for example, are centred on Colombian and Ecuadorian super páramos, while endemics such as Distichia muscoides (Juncaceae), Floscaldasia hypsophila (Asteraceae) and Werneria crassa (Asteraceae) have wider distributions.

In the lower super páramo up to about 4500 m, an open dwarf scrub formation dominated by the endemic Loricaria complanata (Asteraceae) can be found on well-drained soils and rocky outcrops. In the Colombian Cordillera Oriental, associated species include the endemic Agrostis haenkeana (Poaceae), Aciachne pulvinata (Poaceae), Carex pygmaea (Cyperaceae), Lachemilla nivalis (Rosaceae), Puya triane (Bromeliaceae) and Senecio cocuyanus (Asteraceae). In other places particularly on terminal moraines in the Sierra Nevada del Cocuy, a low scrub dominated by Senecio vaccinioides and the endemic Diplostephium rhomboides (Asteraceae) may be encountered. Common associates are the endemic Espeletia lopezii (Asteraceae), Luzula racemosa (Juncaceae) and Senecio formosus (Asteraceae). In undisturbed areas, a thick layer of the possibly endemic acrocarpous moss Zygodon pichinchensis covers many of the branches and trunks of this association. Also found locally in the more humid areas of the lower super páramo of the Sierra Nevada del Cocuy, for example, are stands dominated by stem rosettes of the endemic Espeletia cleefii and Espeletiopsis colombia (Asteraceae). Common associates are the endemic Agrostis breviculmis (Poaceae), Castilleja fissifolia (Orobanchaceae) and Gnaphalium antennarioides (Asteraceae). In places there are extensive areas of unstable gravel screes, which are regularly moving due to the action of freeze and thawing. Here the endemic, rosette species Senecio niveo-aureus (Asteraceae) is often the most characteristic plant. Associates include the giant Lupinus alopecuroides, but many other ecological zonal can be found in the lower super páramo. For example, a zone dominated by the endemic Draba pamplonensis (Brassicaceae) has been recorded in the Sierra Nevada de Mérida, Venezuela, but so far this has not been found the Colombian páramos. The upper super páramo (about 4500-4800 m) shows a distinct reduction in vascular plants, but a few, such as the endemic Luzula racemosa (Juncaceae) and Senecio niveo-aureus (Asteraceae), have been found in sheltered places in the Colombian Cordillera Oriental. Close to the snowline the only life forms include a few lichens such as Stereocaulon vesuvianum and bryophytes like as Racomitrium crispulum.

Northern Andean Aquatic Quillwort (Isoetes) Páramo

These comprise communities of low nutrient páramos lakes dominated by endemic species of Isoetes (Isoetaceae) and aquatic bryophytes. These range in height from a few centimeters (e.g Isoetes socia) to about 60 cm in the giant Isoetes cleefii. Other species include Isoetes andicola, I. boyacensis, I. glacialis, I. karstenii and I. palmeri. All of these species belong to the section Laeves, which appears to have evolved in the neotropics and most are endemic to the tropical Andes. Isoetes karstenii forms a more or less closed community in some of the highest super páramos lakes (up to altitudes of 4425 m), which are often devoid of all other vascular plants. Typical bryophytes include Blindia magellanica, Isotachis serrulata and Fontinalis bogotensis. The tiny plants of Isoetes socia dominate shallow lakes of the high páramo. Here the few vascular plants include Elatine chilensis and the endemic Crassula bonariensis (Crassulaceae) and Ranunculus mandonianus (Ranunculaceae). Isoetes andicola, on the other hand, is completely different. It forms long boggy hummocks up to 80 cm thick along mineral shores in high altitude lakes. Few other species can be found here but the endemic Oritrophium limophilum (Asteraceae) and Plantago rigida (Plantaginaceae) may be present. Isoetes cleefii is also unusual in forming high (20-60 cm) dense communities in clear lakes of the high grass páramo with few other species, although bryophytes such as Calypogeia andicola may be present. Isoetes palmeri is charactersitic of peaty páramo lakes surrounded by boggy areas. A number of herbaceous amphiphytes, such as Eleocharis acicularis and Hydrocotyle ranunculoides are also charactersitic of these lakes. Isoetes glacialis, as the name suggests, occurs in high glacial lakes. These stands are often so dense that virtually all other species are excluded. Finally Isoetes boyacensis is a common dominant in pools on the calcareous slopes of the Páramo de Almorzadera.

Northern Andean Aquatic Páramo with Tillaea paludosa

Vegetation dominated by the endemic Tillaea paludosa (Crassulaceae) is generally found in the shallow small páramo lakes and pools or along the shores of large, deep páramo lakes. Many of these are mesotrophic as opposed to the more nutrient poor (oligotrophic) condition of the ‘Isoetes’ lakes. Other aquatic herbs include Limosella australis and the endemic Juncus ecuadoriensis (Juncaceae), Lilaeopsis schaffneriana (Apiaceae) and Ranunculus limoselloides (Ranunculaceae). Similar aquatic communities have been found in the afro-alpine zone of several African mountains including Kilimanjaro. Here the dominant species include Crassula granvikii and Limosella africana.

Northern Andean Aquatic Páramo with Equisetum bogotense

Pure stand of Equisetum bogotense up to about 25 cm high occur in various Andean aquatic conditions including lakes and rivers such as the Rio Lagunillas (Sierra Nevada del Cocuy). This species is widely distributed in the tropical Andes and also occur in the Galapagos Islands.

Northern Andean Mire and Swamp Páramo

North Andean mires and swamps may be dominated by bryophytes such as Marchantia plicata, cyperoids such as the endemic Carex bonplandi, C. pinchinchensis and Cyperus rivularis (Cyperaceae), graminoids such as the endemic Calamagrostis ligulata (Poaceae), and herbaceous forbs such as Gratiola peruviana and the endemic Galium trianae (Rubiaceae), Geranium confertum (Geraniaceae) or Lupinus alopecuroides (Fabaceae), or shrubby species such as the endemic Senecio reissianus (Asteraceae). Mires characterized by Marchantia occur in the upper páramo, the grass páramo and the upper forest belt. In the Colombian Cordillera other species include Epilobium denticulatum, E. meridense and the endemic Cardamine bonariensis (Brassicaceae), Cerastium imbricatum (Caryophyllaceae) and Stachys ellipica (Lamiaceae).  Galium trianae and Gratiola peruviana are characteristic of certain cyperaceous reed swamps which normally also include the bryophyte Philonotis andina and endemic vascular plants like Lachemilla mandaniana (Rosaceae). This association is found in the humid páramo in places like glacial valley floors and calcareous depressions. Cyperaceous swamps dominated by Carex pinchinchensis have a hummock-hollow relief. They are mainly in the sub páramo or grass páramo and have their optimal development in marshy glacial valleys. Associated species include the endemic Nertera granadensis (Rubiaceae), Valeriana plantaginea (Valerianaceae) and Senecio canescens (Asteraceae). Cyperus rivularis, on the other hand, is more characteristic of poorly drained peat in the wet sub páramo. Lupinus alopecuroides dominates eutrophic wet flushes with a rich herbaceous layer. Other species typically include Mimulus glabratus and the endemic grass Calamagrostis ligulata (Poaceae). The latter species also forms associations with Geranium confertum in páramo mires and marshy lakeshores. Shrubby association in which Senecio reissianus is the dominant shrub occur on eutrophic marshy or peaty ground usually on gently sloping glacial valley floors or in seepage zones. Other species include the endemic Carex pinchinchensis and Rumex tolimensis (Polygonaceae).

Northern Andean Cushion Bog Páramo

Andean bogs dominated by low cushion chamaephytes and geophytes are mainly found at altitudes between 3400-4500 m, but in some locations, such as the Bolivian Andes, these have been recorded up to 5400 m. The key species often include the endemic Castilleja fissifolia (Orobanchaceae), Distichia muscoides (Juncaceae), Plantago rigida (Plantaginaceae) and Werneria pygmaea (Asteraceae). These bogs range across the high tropical Andes from Argentina and Chile to Colombia and Venezuela and correspond roughly to the distribution of the main character species Werneria pygmaea together with some of the small endemic Andean juncaceus genera Distichia, Oxychloe (e.g. Oxychloe andina) and Patosia (e.g. Patosia clandestina). More or less restricted to the northern Andes is the sub-alliance dominated by the endemic Oritrophium limnophilum (Asteraceae) and Werneria pygmaea. This occurs in small, deep valleys and on glacial valley floors, and commonly includes a number of endemic species with very limited distributions including Erigeron paramensis (Asteraceae), Floscaldasia hypsophila (Asteraceae), Vesicarex collumanthus (Cyperaceae) and Werneria crassa (Asteraceae). In places the latter may become dominant in its own right and may be associated with the endemic Lysiopomia sphagnophila (Lobeliaceae), but various other association occur. Another example includes cushion bogs characterized by Altensteinia paludosa and the endemic Castilleja fissifolia (Orobanchaceae) and Gentiana sedifolia (Gentianaceae) together with various bryophytes. This alliance is characteristic of partially filled glacial lakes, and in some of these the cushions actually float. Others are either soligenous or ombrogenous with the latter occurring in the highest parts of bogs and completely dependent on atmospheric water sources. Associated species often include the endemic Cortaderia sericantha (Poaceae).

Northern Andean High Alpine Páramo

There are various types of alpine meadow grasslands in the Andes. Among the dominant grass taxa are the small, endemic tussock species Agrostis foliata and Lorenzochloa erectofolia and the endemic cushion-like species Aciachne pulvinata and Muhlenbergia fastigiata (Poaceae). Aciachne and Lorenzochloa represent monotypic tropandean genera. Grasslands dominated by Lorenzochloa tend to be slightly zerophytic and in the Colombian Cordillera Oriental occur at altitudes ranging from 3500-4350 m. Here the associated species include the endemic Espeletia argentea (Asteraceae), Orthrosanthus chimboracensis (Iridaceae), Paspalum bonplandianum (Poaceae) and Satureja nubigena (Lamiaceae). This association is also rich in Cladonia lichen species. Aciachne grassland also has a zerophytic character. It occurs in dry depressions and on gently sloping dry ground, and can be found throughout the high tropical Andes. Apparently, Aciachne retains moisture from fog and its growth often reflects the direction the fog originates from. Depending on location the associated species may include the endemic Agrostis triochodes, Bromus lanatus (Poaceae), Eryngium humile (Apiaceae), Lachemilla orbiculata (Rosaceae), Niphogeton dissectum (Apiaceae), Oreomyrrhis andicola (Apiaceae), Senecio repens (Asteraceae) and Sisyrinchium trinerve (Iridaceae).  Muhlenbergia fastigiata is characteristic of wet meadows from the upper forest line at about 3500 m to the lowermost limit of the super páramo at 4250 m. The species is widely distributed in the tropical Andes, but the number and composition of associate species largely depends on altitude. Some typical species include the endemic Carex bonplandii (Cyperaceae), Galium trianae (Rubiaceae) and Werneria pygmaea (Asteraceae). The graminoid layer typically has a bluish tinge. Grasslands characterized by Agrostis foliata are usually pioneer communities of humid sandy or silty beaches in the super páramo lakes up to an altitude of about 4700 m. A peculiar feature of this species of Agrostis is its stiff, purplish blades. Acrocarpous mosses make up most of the associated species but other vascular plants may be present such as the endemic grass Calamagrostis ligulata (Poaceae).

Northern Andean Alpine Cushion Plant Páramo

Cushion formations dominated by the endemic Azorella multifida (Araliaceae) can be well developed at altitudes ranging from about 4000-4200 m. Good examples can be seen on the high volcano Nevada de S. Isobel in the Colombian Cordillera Central. At the highest altitudes these formations may be simply represented by solitary cushions of Azorella, which can reach heights of up to 40 cm. In less exposed areas other endemic species may be present such as Gentiana sedifolia (Gentianiaceae) and Lysipomia sphagnophila (Campanulaceae) together with various bryophytes such as Tortula andicola and Zygodon pichinchensis. In fact, a moss layer may cover many of the cushions.

Northern Andean Alpine Bamboo Páramo

Locally at altitudes ranging from 2900-4000 m there are dense stands of the unusual endemic bamboo Neurolepis aristata (Poaceae). It occurs throughout the tropical Andes in the border areas between humid Andean forest and Swallenchloa bamboo páramo, and can reach heights of up to 3 m. In a number of places it achieves almost 100% ground cover with no discernable herbaceous layer. However, there is often a well-shaded ground layer consisting almost entirely of hygrophytic bryophytes.

 

Central Andean Puna (general)

UNESCO described the puna (here regarded as a form of páramo) as an entire phytogeographical area comprising the vegetation of both the altiplano and the neighbouring mountain slopes. It is general described as dry highland vegetation of the Central Andes, while its northern counterpart, the paramo, is generally regarded as wet highland vegetation of the Northern Andes. Nevertheless, puna can still be broadly divided into dry, moist and wet puna. Grasses such as Deyeuxia, Festuca and Poa typically dominate, with prevalence in the dryer areas of Festuca orthophylla and several species of Stipa. Low standing grasses of Muhlenbergia and Distichlis humilis together with halophytic shrubs cover much of the extended salt plains, while local fresh water cushion peat bogs or fens (bofedales or ciénagas) are dominated by the plant families Juncaceae, Cyperaceae and Asteraceae. Few trees besides Polylepis and Buddleja are present today.

Central Andean Dry or Tola Heath Puna

Found at elevation ranging from 3,500-5,000 m, the rainfall in these zones is very seasonal with dry seasons lasting up to eight months. This unique vegetation extends from the Peruvian Western Cordillera crossing the central altiplano in northern Bolivia and then gets restricted to the eastern edge of the altiplano in southern Bolivia. The sparse vegetation is typically dominated by shrubs up to 1 m high often characterized by tola (Parastrephia lepidophylla), but there are also small stands of Polylepis, the only arborescent genus that occurs naturally at these high elevations. Vast areas are also covered by bunch grasses, typically dominated by Festuca orthophylla especially in the slightly wetter areas, and cushion plants may also be present. Other typical plant genera include Aciachne, Adesmia, Margyricarpus and Tetraglochin, and there are various species of Andean camelids. All of the flora and fauna are highly adapted to the extreme conditions.

Central Andean Moist Puna

This seems to be synonymous with humid or grass puna, which covers vast areas from central Peru, where it spans the entire width of the Andes, to the central parts of the Bolivian altiplano where it is confined to a northerly exposed zone adjacent to montane forest. The zone widens again near Santa Cruz but then gradually disappears north of Tarija. The vegetation has well developed ground cover and largely consists of tussock grasses of the genera Calamagrostis, Festuca and Stipa. In between the tussocks are various delicate grasses and herbs. Also present are various rosette plants and cushion plants of the genera Azorella, Aciachne, Distichia, Plantago and the endemic Pycnophyllum (Caryophyllaceae). Cacti are generally rare but large cushion of the wooly Tephrocactus lagopus and T. floccosus can be conspicuous. Around the margins of Lake Titicaca, the humid puna is characterized tussocks of Stipa Ichu and Festuca together with various species of Baccharis, while the mountainous hinterland includes low bushes of Adesmia miraflorensis, Calceolaria parvifolia, Mutisia orbignyana, Satureja boliviana, Tetraglochin cristatum and several species of Senecio.

Central Andean Wet Puna

Wet puna is mainly found in northern Peru, where it is influenced by moist air from both the Amazon Basin and the Pacific Ocean, and along the Eastern Cordillera, where most of the moist air comes from the Amazon Basin. On the altiplano it occurs at elevations ranging from 3,700 to 4,200 m.  On the Eastern Cordillera the vegetation is characterized by several species of Cortaderia. Between the tussocks there are often other grasses, sedges and low-growing forbs, together with ferns such as Jamesonia and lycopods such as Lycopodiella. Mosses and lichens are also common.

Central Andean Cushion Plant Puna

At high elevations over 4,000 m, cushion bogs or bofedales can be found with floating and submerged cushion plants (see below). The larger cushion plants include Distichia muscoides, Oxychloe andina and Plantago rigida, while other genera include Gentiana, Hypsela, Isoetes, Lilaeopsis, Ourisia, and Scirpus. In the less wet areas other cushion plant species occur such as the endemic Azorella compacta (Araliaceae) and Werneria aretioides (Asteraceae). In fact, Azorella compacta extends over vast areas between 4600-5200 m particularly on exposed slopes covered by rocky outcrops.

Central Andean Peat Bog (Bofedales) Puna

Peat is basically the remains of partially decayed plant material that accumulates in waterlogged situations. It is prevented from decaying fully by acidic and anaerobic conditions. However, peat bog are mainly associated with the more humid parts of the world, so it is rather strange that they occur here in one of the most arid parts of the world just east of the Atacama desert. It seems that groundwater is the prominent source of water and they generally lie in the bottoms of narrow, glacially modified alpine valleys or alpine basins at altitudes ranging from 3200-5000 m. Not surprisingly the vegetation of these remarkable peat bogs stands out in marked contrast to the surrounding vegetation. Much of it is composed of compact cushion plant formations (see above) mainly Oxychloe andina and Patosia clandestina while grasses such as Distichia filamentosa and D. muscoides dominate the ‘lawn’ and hummock formations. Sphagnum moss is also characteristic especially in northern peatlands. Wet peripheral areas typically include Deschampsia caespitosa, Deyeuxia velutina together with various species of Carex and Eleocharis.

Central Andean Aquatic Puna

In the Nevado Coropuna volcano area of southern Peru the aquatic vegetation often includes Azolla filiculoides and Ranunculus limoselloides, while the marshy areas typically include Distichia muscoides, Lilaeopsis macloviana, species of Carex and the endemic Werneria pygmaea (Asteraceae). Characteristic of the drier marsh margins are Calamagrostis ovata together with species of Astragalus and Lupinus. The aquatic vegetation of Lake Titicaca is characterized by Elodea potamogeton Juncus arcticus subsp andicola, Myriophyllum quitensis and Schoenoplectus californicus subsp. tatora. Growing in the shallow margins of high-Andean lakes in the centre-north of the eastern ranges of Bolivia are swards characterized by Lachemilla diplophylla and Lilaeopsis macloviana. These areas often become completely dry towards the end of the dry season. Other species here include Alopecurus hitchcockii, Cotula mexicana, Deyeuxia jamesonii, Distichia muscoides, Oritrophium limnophilum and Plantago tubulosa.

Central Andean Shrubland Steppe Puna

From east to west the vegetation gradually changes from shrubland steppe with xerophilous shrubs such as Adesmia, Baccharis, Fabiana, and Senecio to grassy steppe with grasses of the genera Calamogrostis, Festuca, and Stipa.Some of the common shrubs are Baccharis incarum, B. boliviensis, Parastrephila lepidophylla and Fabiana densa. These can reach heights of up to 2.5 m. On the Nevado Coropuna volcano in southern Peru there are stands of shrubby vegetation characterised by Mutisia acuminata (Asteraceae), together with species of Fabaceae and Solanaceae. Associated species include various endemics such as Chersodoma arequipensis, Diplostephium tacorense (Asteraceae) and Opuntia corotilla (Cactaceae).

Central Andean High Altitude Formations

Above the puna region, at altitudes between about 4200 m and the highest limit of vegetation, grows sparse communities dominated by a few grasses such as Deyeuxia, Poa, together with endemics such as Anthochloa lepidula, Dielsiochloa floribunda, Dissanthelium calycinum, D. trollii and D. macusaniense and a large number of cushion plants, rosette and dwarf shrubs (Azorella, Xenophyllum and the endemic Pycnophyllum, Nototriche, and Werneria,). At slightly lower altitudes denser grass swards develop with Agrostis, Deyeuxia (e.g Deyeuxia minima), Poa and Stipa. Associated taxa include Luzula racemosa, species of Gentianella and Trichophorum and the endemic Oreobolopsis tepalifera (Cyperaceae), together with various perennial herbs. Most common plant families include Asteraceae, Caryophyllaceae, Geraniaceae and Malvaceae.

 

References

Anon. 1996. Habitats of South America. Institute of Terrestrial Ecology and Intitut Royal Des Sciences Naturelles De Belgique.

Beck, S.G., 1985. Florula ecológica de Bolivia: Puna semiárida en el Altiplano Boliviano. Ecología en Bolivia, 6: 1-41.

Borchsenius, F. 1997. Patterns plant species diversity in Ecuador. Biodiversity and Conservation, 6: 379-399.

Brako, L & Zarucchi, J. 1993. Catalogue of the flowering plants and gymnosperms of Peru. Missouri Botanical Garden.

Cabrera, A.L.1968. Ecologia vegetal de la puna. In: Geoecology of the mountainous regions of the tropical Americas. Ed. C. Troll. Colloquium Geographicum Vol. 9, Ferd. Dummerlers Verlag, Bonn.

Cleef, A. M. 1979. The phytogeographical position of the neotropical vascular Paramo flora with special references to the Colombian Cordillera Oriental. In: Tropical Botany. Eds. K. Larsen and L. B. Holm-Nielsen. Academic Press.

Cleef, A. M. 1981. The vegetation of the Páramos of the Colombian Cordillera Oriental. Dissertationes Botanicae Band 61. J. Cramer.

Cuatrecasas, J. 1968. Paramo vegetation and its life forms. In: Geo-Ecology of the Mountainous Regions of Tropical Americas. Ed. C. Troll. Proceedings of the UNESCO Mexican Symposium 1966. Verlag.

Davis, S. D., V. H. Heywood, O. Herrera-MacBryde, J. Villa-Lobos & A. C. Hamilton. 1997. Altoandina Argentina, Chile. Centres of plant diversity: A guide and strategy for their conservation, Vol. 3 The Americas. Eds. S.D. Davis, V.H. Heywood, O. Herrera-MacBryde, J. Villa-Lobos and A C. Hamilton IUCN, WWF, Oxford, UK.

Forero, E. 1988. Botanical exploration and phytogeography of Colombia: past, present and future. Taxon, 37: 561-566.

Galán de Mera, A., Cáceres, C. & González, A. 2003. La vegetación de la alta montana andina del sur del Peru. Acta Botanica Malacitana, 28: 121–147.

Hammen, T. van der. 1979. History of the flora, vegetation and climate in the Colombian Cordillera Oriental during the last five million years. In: Tropical Botany. Eds. K. Larsen and L. B. Holm-Nielsen. Academic Press.

Hammen, T. van der. & Cleef, A. M. 1986. Development of the high Andean paramo flora and vegetation. In: High Altitude Tropical Biogeography. Eds. F. Vuilleumier and M. Monasterio. Oxford University Press and American Museum of Natural History.

Harling. G. 1979. The vegetation types of Ecuador a brief survey. In: Tropical Botany. Eds. K. Larsen and L. B. Holm-Nielsen. Academic Press.

Jorgenson, P. M. & León-Yánez, S. (eds). 1999. Catalogue of the Vascular Plants of Ecuador. Monographs in Systematic Botany from the Missouri Botanical Gardens, 75: 1-1169.

Jorgenson, P. M. & Ulloa, C. U. 1994. Seed plants of the high Andes of Ecuador – a checklist. Department of Systematic Botany, University of Aarhus, Denmark. AAU Reports 34.

Junk, W. J. 1993. Wetlands of tropical South America. In: Wetlands of the World: Inventory, ecology and management. Vol. 1. Eds. D. Whigham, D. Dykyjova and S. Hejny. Kluwer Academic Press.

Kessler, M. 2002. The elevational gradient of Andean plant endemism: varying influences of taxon-specific traits and topography at different taxonomic levels. Journal of Biogeography, 29: 1159-1165.

Krömer, T., Kessler, M., Gradstein, S. R. & Acebey, A. 2005. Diversity patterns of vascular epiphytes along an elevation gradient in the Andes. Journal of Biogeography, 32: 1799-1809.

Kuentz, A., Galán de Mera, A. G. de., Ledru, M-P. & Thouret, J-C. 2007. Phytogeographical data and modern pollen rain of the puna belt in southern Peru (Nevado Coropuna, Western Cordillera). Journal of Biogeography, 34: 1762–1776.

Luteyn, J. L. 1999. Paramos – a checklist of plant diversity, geographical distribution and botanical literature. Memoirs of The New York Botanical Garden, Volume 84.

Molina, J. A., Navarro, G., Barra, N. De la & Lumbreras, A. 2007. Andean aquatic vegetation in central Bolivia. Phytocoenologia, 37: 753-768.

Sklenár, P. 2006. Searching for altitudinal zonation: species distribution and vegetation composition in the superpáramo of Volcán Iliniza, Ecuador. Plant Ecology, 184: 337-350.

Sklenár, P. & Balslev, H. 2004. Superpáramo plant species diversity and phytogeography in Ecuador. Flora, 200: 416-433.Steyermark, J. A. 1979. Plant refuge and dispersal centres in Venezuela: their relict and endemic elements. In: Tropical Botany. Eds. K. Larsen and L. B. Holm-Nielsen. Academic Press.

Vargas, M. F. R., Cruz, M. L. &  Rivero, A. L. 2003. Lake Titicaca. Lake Basin Management Initiative. Experience and Lessons Learned Brief. A paper presented at the Lake Basin Management Initiative Regional Workshop for Europe, Central Asia and the Americas held at Saint Michael’s College in Vermont, USA. 2003.

Warner, B. G., Aravena, R. & Squeo F. A. 2008. Peatlands on the Altiplano Plateau of the Central Andes. PEATLANDS International, 1/2008.

Werff, H. Van Der. & Consiglio, T. 2004. Distribution and conservation significance of endemic species of flowering plants in Peru. Biodiversity and Conservation, 13: 1699-1713.

Young, K.R., B. Leon, A. Cano & O. Herrera-MacBryde. 1997. Peruvian Puna Peru. In: Centres of plant diversity: A guide and strategy for their conservation, Vol. 3 The Americas. Eds. S.D. Davis, V.H. Heywood, O. Herrera-MacBryde, J. Villa-Lobos and A C. Hamilton. IUCN, WWF, Oxford, U.K.