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Rename sections #17
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jrfep committed May 10, 2022
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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_1.md
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These tropical swamps have closed forest canopies and experience high rainfall and consistent temperatures all year. In some, peat accumulates in anaerobic black water conditions, while others are highly productive white-water systems, with frequent refilling and turnover of nutrients. Trees and other plants, such as palms, pitcher plants, epiphytic mosses and ferns grow in soils that are waterlogged or periodically inundated.

# Ecological Traits
# Ecosystem Properties

Closed-canopy forests in tropical swamps and riparian zones have high biomass and LAI, with unseasonal growth and reproductive phenology. The canopy foliage is evergreen, varying in size from mesophyll to notophyll with moderate SLA. Productivity differs markedly between high-nutrient ‘white water’ riparian systems and low-nutrient ‘black water’ systems. In the latter, most of the nutrient capital is sequestered in plant biomass, litter, or peat, whereas in white water systems, soil nutrients are replenished continually by fluvial subsidies. Some trees have specialised traits conferring tolerance to low-oxygen substrates, such as surface root mats, pneumatophores, and stilt roots. Palms (sometimes in pure stands), hydrophytes, pitcher plants, epiphytic mosses, and ferns may be abundant, but lianas and grasses are rare or absent. The recent origin of these forests has allowed limited time for evolutionary divergence from nearby lowland rainforests ([T1.1](/explore/groups/T1.1)), but strong filtering by saturated soils has resulted in low diversity and some endemism. The biota is spatially structured by local hydrological gradients. Riparian galleries of floodplain forests also occur within savanna matrices. Trophic networks are complex but with less diverse representation of vertebrate consumers and predators than [T1.1](/explore/groups/T1.1), although avian frugivores, primates, amphibians, macro-invertebrates, and crocodilian predators are prominent. Plant propagules are dispersed mostly by surface water or vertebrates. Seed dormancy and seedbanks are rare. Gap-phase dynamics are driven by individual treefall, storm events, or floods in riparian forests, but many plants exhibit leaf-form plasticity and can recruit in the shade.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

High rainfall, overbank flows or high water tables maintain an abundant water supply. Continual soil profile saturation leads to anaerobic black water conditions and peat accumulation. In contrast, white water riparian zones undergo frequent fluvial disturbance and drain rapidly. Peat forests often develop behind lake shore vegetation or mangroves, which block lateral drainage. Black water peatlands may become domed, ombrogenous (i.e. rain-dependent), highly acidic, and nutrient-poor, with peat accumulating to depths of 20 m. In contrast, white water riparian forests are less permanently inundated and floods continually replenish nutrients, disturb vegetation, and rework sediments. Hummock-hollow micro-topography is characteristic of all forested wetlands and contributes to niche diversity. Light may be limited by dense tree canopies. There is low diurnal, intra- and inter-annual variability in rainfall and temperature, with the latter rarely <10°C, which promotes microbial activity when oxygen is available.

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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_2.md
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Forested wetlands in temperate and subtropical climates undergo periodic flooding. One or two tree species dominate the canopy. Trees shape the flow of flood waters, the ground surface, and the understorey, as well as animal habitats. With flooding, complex aquatic food webs support turtles, frogs, fish and birds, but can produce microbial blooms with nutrients flushed from the floodplain. Many vertebrates use these wetlands as refuges during dry times.

# Ecological Traits
# Ecosystem Properties

These hydrophilic forests and thickets have an open to closed tree or shrub canopy, 2–40 m tall, dependent on flood regimes or groundwater lenses. Unlike tropical forests ([TF1.1](/explore/groups/TF1.1)), they typically are dominated by one or very few woody species. Trees engineer fine-scale spatial heterogeneity in resource availability (water, nutrients, and light) and ecosystem structure, which affects the composition, form, and functional traits of understorey plants and fauna. Engineering processes include the alteration of sediments, (e.g. surface micro-topography by the growth of large roots), the deposition of leaf litter and woody debris, canopy shading, creation of desiccation refuges for fauna and the development of foraging or nesting substrates (e.g. tree hollows). Forest understories vary from diverse herbaceous assemblages to simple aquatic macrophyte communities in response to spatial and temporal hydrological gradients, which influence the density and relative abundance of algae, hydrophytes and dryland plants. Primary production varies seasonally and inter-annually and can be periodically high due to the mobilisation of nutrients on floodplains during inundation. Nutrients accumulate on floodplains during low flows, and may drive microbial blooms, leading to aquatic anoxia, and fish kills, which may be extensive when flushing occurs. Plant and animal life histories are closely connected to inundation (e.g. seed-fall, germination fish-spawning and bird breeding are stimulated by flooding). Inundation-phase aquatic food webs are moderately complex. Turtles, frogs, birds and sometimes fish exploit the alternation between aquatic and terrestrial phases. Waterbirds forage extensively on secondary production, stranded as floodplains recede, and breed in the canopies of trees or mid-storey. Forested wetlands are refuges for many vertebrates during droughts. Itinerant mammalian herbivores (e.g. deer and kangaroos) may have locally important impacts on vegetation structure and recruitment.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

These forests occur on floodplains, riparian corridors, and disconnected lowland flats. Seasonally and inter-annually variable water supply influences ecosystem dynamics. Allochthonous water and nutrient subsidies from upstream catchments supplement local resources and promote the extension of floodplain forests and their biota into arid regions (‘green tongues’). Water movement is critical for the connectivity and movement of biota, while some groundwater-dependent forests are disconnected. High-energy floods in riparian corridors displace standing vegetation and woody debris, redistribute nutrients, and create opportunities for dispersal and recruitment. Low-energy environments with slow drainage promote peat accumulation. Extreme drying and heat events may generate episodes of tree dieback and mortality. Fires may occur depending on the frequency of fire weather, ignition sources, and landscape context.

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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_3.md
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Permanent marshes occur throughout tropical and temperate regions of the world in flat areas with stable water levels close to the surface. They are essentially treeless, with extensive reedbeds and aquatic grasses, interspersed with patches of open water. Food webs are strongly influenced by highly productive algae and plants, providing food for large numbers of invertebrates, waterbirds, reptiles, and mammals.

# Ecological Traits
# Ecosystem Properties

These shallow, permanently inundated freshwater wetlands lack woody vegetation but are dominated instead by emergent macrophytes growing in extensive, often monospecific groves of rhizomatous grasses, sedges, rushes, or reeds in mosaics with patches of open water. These plants, together with phytoplankton, algal mats, epiphytes, floating, and amphibious herbs, sustain high primary productivity and strong bottom-up regulation. Although most of the energy comes from these functionally diverse autotrophs, inflow and seepage from catchments may contribute allochthonous energy and nutrients. Plant traits including aerenchymatous stems and leaf tissues (i.e. with air spaces) enable oxygen transport to roots and rhizomes and into the substrate. Invertebrate and microbial detritivores and decomposers inhabit the water column and substrate. Air-breathing invertebrates are more common than gill-breathers, due to low dissolved oxygen. The activity of microbial decomposers is also limited by low oxygen levels and organic deposition continually exceeds decomposition. Their aquatic predators include invertebrates, turtles, snakes and sometimes small fish. The emergent vegetation supports a complex trophic web including insects with winged adult phases, waterbirds, reptiles, and mammals, which feed in the vegetation and also use it for nesting (e.g. herons, muskrat, and alligators). Waterbirds include herbivores, detritivores, and predators. Many plants and animals disperse widely beyond the marsh through the air, water and zoochory (e.g. birds, mammals). Reproduction and recruitment coincide with resource availability and may be cued to floods. Most macrophytes spread vegetatively with long rhizomes but also produce an abundance of wind- and water-dispersed seeds.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

These systems occur in several geomorphic settings including lake shores, groundwater seeps, river floodplains, and deltas, always in low-energy depositional environments. Shallow but perennial inundation and low variability are maintained by frequent floods and lake waters, sometimes independently of local climate. This sustains high levels of water and nutrients but also generates substrate anoxia. Substrates are typically organic. Their texture varies, but silt and clay substrates are associated with high levels of P and N. Salinity is low but may be transitional where wetlands connect with brackish lagoons ([FM1.2](/explore/groups/FM1.2), [FM1.3](/explore/groups/FM1.3)). Surface fires may burn vegetation in some permanent marshes, but rarely burn the saturated substrate, and are less pervasive drivers of these ecosystems than seasonal floodplain marshes ([TF1.4](/explore/groups/TF1.4)).

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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_4.md
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Seasonal flooding and drying regimes characterise high productivity floodplain marshes in the seasonal tropics and subhumid temperate regions. Typically, different plants respond to the mosaic of variable flooding regimes, supporting complex networks of invertebrates, waterbirds, reptiles, and mammals. Prey concentrate as the wetlands dry, and many plants and animals use specialised adaptations such as seed banks or egg banks, to survive drying.

# Ecological Traits
# Ecosystem Properties

This group includes high-productivity floodplain wetlands fed regularly by large inputs of allochthonous resources that drive strong bottom-up regulation, and smaller areas of disconnected oligotrophic wetlands. Functionally diverse autotrophs include phytoplankton, algal mats and epiphytes, floating and amphibious herbs and graminoids, and semi-terrestrial woody plants. Interactions of fine-scale spatial gradients in anoxia and desiccation are related to differential flooding. These gradients shape ecosystem assembly by enabling species with diverse life-history traits to exploit different niches, resulting in strong local zonation of vegetation and high patch-level diversity of habitats for consumers. Wetland mosaics include very productive and often extensive grasses, sedges and forbs (sedges dominate oligotrophic systems) that persist through dry seasons largely as dormant seeds or subterranean organs, as well as groves of woody perennials that are less tolerant of prolonged anoxia but access ground water or arrest growth during dry phases. Productive and functionally diverse autotrophs support complex trophic networks with zooplankton, aquatic invertebrates, fish, amphibians, reptiles, aquatic mammals, waterbirds, and terrestrial animals with diverse dietary and foraging strategies. During dry phases, obligate aquatic organisms are confined to wet refugia. Others, including many invertebrates, have dormancy traits allowing persistence during dry phases. Very high abundances and diversities of invertebrates, waterbirds, reptiles, and mammals exploit resource availability, particularly when prey are concentrated during drawdown phases of floods. Reproduction and recruitment, especially of fish, coincide with food availability cued by flood regimes.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

Regular seasonal flooding and drying is driven by river flow regimes, reflecting seasonal precipitation or melt patterns in catchments. Salinity gradients and tides influence these marshes where they adjoin estuaries, with brackish marshes on transitions to [TF1.2](/explore/groups/TF1.2), [TF1.3](/explore/groups/TF1.3) and [MFT1.3](/explore/groups/MFT1.3). Disconnected oligotrophic systems rely on rainfall and low substrate permeability for seasonal waterlogging. Seasonal flood extent and duration vary inter-annually, especially in temperate zones. Geomorphic heterogeneity in the depositional floodplains promote spatial and temporal variability in moisture status, creating contrasting patches including perennially inundated refuges and dry ‘islands’ that seldom flood and dry rapidly. Substrates are fertile alluvia or infertile white sands with variable grain sizes, moisture, and organic content that reflect fine-scale depositional patterns and hydrological gradients. Fires may occur in dry seasons, releasing resources, changing vegetation structure and composition, consuming organic substrates and lowering the wetland surface.

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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_5.md
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Episodic arid floodplains rarely flood and are predominantly dry, sometimes for years. They are supplied by temporary rivers in semi-arid and arid regions of all continents. When floods come, there is a spike in productivity as nutrients mobilise from leaf litter and organic matter. At such times, dormant plants and animals form complex food webs, capitalising on short periods of high productivity.

# Ecological Traits
# Ecosystem Properties

Highly episodic freshwater floodplains are distinct from, but associated with, adjacent river channels, which provide water and sediment during flooding. These are low-productivity systems during long, dry periods (maybe years), with periodic spikes of very high productivity when first inundated. These floodplains have a high diversity of aquatic and terrestrial biota in complex trophic networks, with ruderal life-history traits enabling the exploitation of transient water and nutrient availability. Primary producers include flood-dependent macrophytes and algae with physiological traits for water conservation or drought avoidance. Lower trophic levels (e.g. algae, invertebrate consumers) avoid desiccation with traits such as dormant life-cycle phases, deposition of resting eggs (e.g. crustaceans and rotifers), and burial in sediments banks (e.g. larvae of cyclopoid copepods). Higher trophic levels (e.g. fish, amphibians, reptiles, and waterbirds) are highly mobile in large numbers or with resting strategies (e.g. burrowing frogs). These taxa can be important mobile links for the movement of biota and resources, but floods are the primary allochthonous sources of energy and nutrients. Floods are important triggers for life-history processes such as seed germination, emergence from larval stages, dispersal, and reproduction. Common lifeforms include detritus-feeding invertebrate collector-gatherers, indicating a reliance on heterotrophic energy pathways.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

Multi-year dry periods are punctuated by brief intervals of shallow inundation caused by the overspill from flooding river channels. These boom-bust systems have temporarily high productivity driven by water and partly by elevated levels of dissolved Carbon and nutrients (notably N and P) released from leaf litter, oxygen, and organic matter in newly inundated, shallow areas. High temperatures promote productivity and rapid drying in arid environments. Water may be turbid or clear, which affects light environments and may limit benthic algal production to the shallow littoral margins of small channels. This in turn affects aquatic food webs and Carbon dynamics. Drainage is predominantly horizontal and bidirectional (i.e. in and out of the river), but infiltration and evapotranspiration can be significant in the flat terrain and may influence salinity if there are sources of salt in the catchment or ground water.

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4 changes: 2 additions & 2 deletions _posts/explore/2_groups/0100-01-01-tf_1_6.md
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Peat bogs in the boreal-subarctic and temperate areas of the world account for up to 40% of the world’s soil carbon. They are landscape sponges, with highly specialised plant life including shrubs, sedges and mosses equipped to grow in acidic, nutrient-poor, low-oxygen, waterlogged soils. Sphagnum moss and other peat-forming plants are foundational to these ecosystems. Insects are the dominant animal group, along with amphibians, reptiles, rodents and a few visiting birds.

# Ecological Traits
# Ecosystem Properties

These patterned peatlands account for up to 40% of global soil carbon are dominated by a dense cover (high LAI) of hydrophytic mosses, graminoids, and shrubs, sometimes with scattered trees. Positive feedbacks between dense ground vegetation, hydrology, and substrate chemistry promote peat formation through water retention and inhibition of microbial decomposition. Moderate to low primary production is partially broken down at the soil surface by anamorphic fungi and aerobic bacteria. Burial by overgrowth and saturation by the water table promotes anaerobic conditions, limiting subsurface microbial activity, while acidity, nutrient scarcity, and low temperatures enhance the excess of organic deposition over decomposition. Plant diversity is low but fine-scale hydrological gradients structure vegetation mosaics, which may include fens ([TF1.7](/explore/groups/TF1.7)). Mosses (notably Sphagnum spp.) and graminoids with layering growth forms promote peat formation. Their relative abundance influences microbial communities and peat biochemistry. Plant traits such as lacunate stem tissues, aerenchyma, and surface root mats promote oxygen transport into the anaerobic substrate. Woody plant foliage is small (leptophyll-microphyll) and sclerophyllous, reflecting excess carbohydrate production in low-nutrient conditions. Plants and fungi reproduce primarily by cloning, except where disturbances (e.g. fires) initiate gaps enabling recruitment. Pools within the bogs have specialised aquatic food webs underpinned by algal production and allochthonous carbon. Invertebrate larvae are prominent consumers in the trophic network of bog pools, and as adults they are important pollinators and predators. Assemblages of flies, dragonflies, damselflies, caddisflies and other invertebrates vary with the number, size and stability of pools. Carnivorous plants (e.g. sundews) support N cycling. Vertebrates are mostly itinerant but include specialised resident amphibians, reptiles, rodents, and birds. Some regions are rich in locally endemic flora and fauna, particularly in the Southern Hemisphere.

[DIAGRAM]

# Key Ecological Drivers
# Ecological Drivers

Bogs are restricted to cool humid climates where moisture inputs (e.g. precipitation, seepage, and surface inflow) exceed outputs (e.g. evapotranspiration, percolation, and run-off) for extended periods, enabling these systems to function as landscape sponges. Seasonally low temperatures and/or frequent cloud cover limit evapotranspiration. Substrates are waterlogged, anaerobic, highly organic (usually >30% dry weight), acidic (pH 3.5–6), and nutrient-poor. Peat growth may produce raised ombrotrophic bogs entirely fed by rain, but if minerotrophic inflows from catchments occur, they provide limited nutrient subsidies (cf. [TF1.7](/explore/groups/TF1.7)). Fires may occur in dry summers, sometimes igniting peat with long-term consequences for ecosystem function and stability.

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