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Allocating taxa to PFTs In principle, most species belongs to a single PFT. However, pollen taxa can be assigned to multiple PFTs because they contain multiple species with different behaviour/responses. It is important that the taxa to PFT allocation is done as precisely as possible, to avoid introducing noise into the biomisation process. In some cases, knowledge about the behaviour of a taxon is incomplete, so we have to pool information from different regions/experts as far as possible. The important thing to recognise here is that the classes of descriptors are meant to describe “obligate behaviour”. For example, if it says “yes” under evergreen and deciduous, it means that some species in the taxon are evergreen and some are deciduous. Similarly, but perhaps more problematically, if it says yes under tropical, temperate and arctic it means that some species in the taxon are obligate tropical, some obligate temperate and some obligate arctic. It does NOT mean that the taxon is found across the temperature range from artic to tropical – if this were the case, we would want to assign it to eurythermic on the assumption that its distribution is influenced by e.g. moisture rather than temperature. The terminology that we use for different parts of the description of a PFT is not ideal. Some of the terms have multiple (or emotive) meanings in the literature. It is important that we try and stick to the definitions below: Non-native: we do not use introduced species in the biomisation in part because they may be growing in “protected” environments and in part because they may impact the scheme and render it less useful for palaeo-reconstructions. We keep these species in the dataset for diagnostic purposes (i.e. how abnormal/contaminated is the sample). We generally define non-natives as species that have been introduced within the last 200-300 years. Other categories not used in biomisation: general terms (e.g. unknown), Pre-Quaternary contaminants (e.g. Cingulatisporites), groups that reflect local or non-climatic factors (intrazonal groups) such as liverworts, mangroves, groups that reflect depositional context (e.g. algae, obligate aquatics, rushes), groups that reflect land use (e.g. cultivated). Moss: small, soft non-flowering non-seeding plants, commonly growing in clumps or mats. Wquivalent to Bryophyta minus liverworts and hornworts (see above) Geophyte: a perennial herbaceous plant with an underground storage organ for reserves of carbohydrates, nutrients, and/or water. Include species that over-winter as bulbs, corms, tubers, rhizomes, tuberous roots, and enlarged hypocotyls. Tuft tree: tree form where leaves emerge from trunk rather than from branches (e.g.palms) Tuft treelet: species with leaves emerging from trunk rather than branches, but which never grows >2-3m high Fern (and fern allies) (Pteridophyta): seedless plants which disperse by shedding spores to initiate an alternation of generations. Includes true ferms (Filicopsida) clubmosses (Lycopsida), horsetails in Sphenopsida/Equisetopsida, and whisk ferns (Psilopsida). Tree fern: a fern that grows with a trunk to elevate the fronds above ground level Eurythermic fern: fern or fern ally which grows in locally-protected habitats and for which the distribution is not apparently affected by regional-scale temperature Tropical fern: fern or fern ally which is confined to regions which do not experience frost Succulent: plants which has mechanisms for storing water in leaves or stem. In the field, can be identified by fleshy nature of leaves or stem. Succulents yield water when leaf or stem is broken. Many have CAM photosynthesis. Sedge: monocot flowering plants in the family Cyperaceae Grass: monocot green plant in the family Poaceae. Note that functionally grasses include trees (e.g. bamboo), shrub-like forms (e.g. African bunch grasses) and small forblike forms. Forb: are herbaceous flowering plants that are not graminoids (grasses, sedges and rushes). C3/C4: describes photosynthetic pathway. Annual: Life cycle completed in a single year. Perennial: plant over-winters and completes life cycle in more than one year. Eurythermic: wide temperature range. In practice, we do not generally expect eurythermic plants to survive arctic temperatures. Tropical: frost-intolerant, i.e. plants that cannot survive frost and require warm winters. In practice, this generally means plants that are confined to regions with winter temperature (MTCO) >15ºC. However, given that the occurrence of frost can be influenced by local factors such as closeness to water, the overwhelming criteria has to be that there is no known mechanism for surviving frost. Temperate: has mechanisms for survival when frost occurs and does not require warm winters. In practice, this generally means MTCO <15ºC. We do not subdivide this category when classifying e.g. forbs but subdivide it (into warm-temperate and cool-temperate) for shrubs/trees. Warm-temperate: frost-sensitive. In practice, regions where MTCO > 5 ºC Cool-temperate: frost-tolerant and may require chilling for bud-burst to take place. In practice, regions where MTCO is between 0-5 ºC Boreal: have mechanisms to tolerate very low temperatures in winter, including e.g. freeze-drying. In practice this means MTCO is never above 0 ºC and the winters are never warm. NOTE: “boreal” conditions can occur e.g. in the geographical tropics, e.g. in mountains. Arctic: has no known minimum temperature limits or require snow-cover to survive winter conditions. NOTE: “arctic” conditions can occur on mountains, so we use this term to cover “alpine” Drought-tolerant: can sustain life through periods of >3 weeks when there is no plantavailable water. Evergreen: maintains leaves throughout the year because leaves are replaced continuously. NOTE: leaves do NOT have to be retained for more than one year for the species to be classified as evergreen. Drought-deciduous: loses leaves in response to drought conditions. This can be a regular occurrence, with loss during the driest part of the year (true drought deciduous), or an irregular occurrence during drought periods (i.e. includes the categories “semi-deciduous” and “semi-evergreen”). Cold-deciduous: regularly loses its leaves in the coldest season in response to cold. Note: species which lose their leaves as a result of catastrophic/unusual weather conditions but which would otherwise not do so ARE NOT considered cold deciduous. Leaves: for the purpose of the classification, leaves means functional leaves (i.e. would include phyllodes that act as leaves) Broadleaved: includes all potentially broad-leaved plants, including plants with small-leaves and essentially leafless plants that exhibit stem photosynthesis Needleleaved: includes true needles, scale-leaved and sheath-leaved plants. Malacophyll: soft leaves, with little protection against water loss from leaf surface and/or stomata. In the field, can be bent without damage. Sclerophyll: exhibits functional traits to minimise water loss (e.g. waxy coatings, reduced stomatal density, hairs, leaf curling) or structural adaptations to lengthen leaf life (e.g. rigidity, strengthening tissue). In the field, sclerophyll leaves will break or crack when bent. Shrubs: for the purpose of the classification, shrubs are multi-stemmed plants which are generally < 3m high whereas trees are single-stemmed plants that are generally > 3m high. (I know this poses some problems with multi-stemmed trees in Australia). Low to high shrub. Shrub that under optimal conditions will grow taller than ca 0.5m Dwarf shrub: Shrub that under optimal conditions never grows taller than ca 0.5m. Would include erect and prostrate forms, cushion shrubs etc. Small-leaved shrub: Shrub of any height that has leaves smaller than ca 5 mm long (i.e. pico-sized leaves). Characteristic of heathlands. Resprouter: readily regenerates after damage by resprouting. Here our main emphasis is damage by fire Shade-tolerant: will regenerate under the canopy There are some functional inconsistencies in these definitions (e.g. our definition of needleleaved plants) and we might like to discuss these at the next meeting. However, to take these into account, we would need to further subdivide our PFTs – something for a later stage. For the moment, PLEASE stick to the definitions above. If you find something that really doesn’t fit into an existing definition/PFT category, please identify the problem. DO NOT try and fit it into the nearest definition/PFT category – we’ve done that before and …. We have two groups of taxa that we might want to consider for biomisation: mistletoes and orchids. Mistletoes as diagnostic of e.g. temperate forests and orchids as diagnostic of e.g. tropical forests. Comments on this would be welcome. Having read this, we would like you to go through the attached Excel file carefully and look at the taxa from your region. Please add missing information and correct any mistakes that you can see (in colour, if possible). We have organised the three sheets so that you only have to consider the information required for each PFT. PLEASE NOTE: According to our preliminary classification, some taxa display different behaviour patterns in different climates (e.g. tropical species are drought-tolerant while warmtermperate species are drought-intolerant); in these situations, the taxon has two entries in the attached table. Where the behaviour pattern is the same except with respect to temperature (i.e. obligate tropical, obligate warm-temperate species are both droughttolerant), then there is only one line entry. If you need to refine theone line entries, either specify as a note at the end of the line or add a line showing the different behaviour patterns.