(writing in progress)
GORONGOSA
The following refer to woody plants taller than 3 m; by numbers of spp., not individuals.
Miombo canopy consists of about six spp., most being ballistic. Brachystegia is dominant, Julbernardia, Millettia, also ballistic (seeds strike other tree boles)
Mesic Miombo 50% zoochorous (e.g. Rubiaceae), 42% anemochorous, 7% ballistic
Xeric Miombo 18% zoochorous, 78% anemochorous (e.g. Combretum), 3% ballistic
Ken believes that soil moisture is responsible, in miombo
Succession on termite mounds:
Slopes of Gorongosa mountain:
Montane thicket (Buddleia, Philippia https://www.inaturalist.org/taxa/637251-Erica-hexandra, Widdringtonia https://www.inaturalist.org/taxa/135521-Widdringtonia-nodiflora, Nuxia https://www.inaturalist.org/taxa/340348-Nuxia-oppositifolia) 70% zoochorous, 4% anemochorous
Montane forest 85% zoochorous, distributed through all strata
Transitional forest (two-thirds of the way down the mountain) 65% zoochorous, 18% ballistic (e.g. Millettia stuhlmannii, https://www.inaturalist.org/taxa/339372-Millettia-stuhlmannii)
Tropical forest (Newtonia buchananii https://www.inaturalist.org/taxa/133937-Newtonia-buchananii and 'Teleopsis murch') 75% zoochorous, 25% anemochorous
Riverine forest (not the same as swamp forest, which is oligotrophic) 70% zoochorous, 18% anemochorous (among canopy trees, e.g Albizia, whi hnhas light pods that split to expose the seeds, without throwing them out, similarly to Vachellia seyal)
Swamp forest (black-water system, waterlogged and anaerobic)(not the same as riverine forest):
Breonadia salicina https://www.inaturalist.org/taxa/429244-Breonadia-salicina is dominant (mode of dispersal uncertain)
Barrington racemosa https://www.inaturalist.org/taxa/196659-Barringtonia-racemosa is subdominant
Synsepalum brevipes https://www.inaturalist.org/taxa/867589-Synsepalum-brevipes third in abundance zoochorous (birds) fruits succulent but mucilaginous and borne in small quantity
Parkia https://www.inaturalist.org/taxa/133527-Parkia-filicoidea (pollinated by bats)
Khaya uncommon (elsewhere a big tree on river banks) anemochorous
Syzygium guineense zoochorous
Bridelia micrantha yellow fruits similar to Celtis (one of the few euphorbs with succulent fruits)
Homalium https://www.inaturalist.org/taxa/587545-Homalium-dentatum possibly zoochorous
Ficus zoochorous
Erythroxylon red succulent fruit in understorey
Craterispermum https://www.inaturalist.org/taxa/473302-Craterispermum-schweinfurthii
Almost all of the thicket and forest types of the Gorongosa area have mainly animal-dispersed woody spp. However, in drier, presumably more fire-prone types, e.g. miombo, <50% of the woody spp. are animal-dispersed. In dry savanna woodland with e.g. Combretum, only 18% of woody spp. are animal-dispersed (and presumably an even smaller percentage have succulent fruits). Here, ballistic and wind-dispersal predominate in the canopy. The incidence of succulent fruits is also small in oligotrophic swamp forest - in sharp contrast to nearby forest on termite mounds. The incidence of succulent fruits is greatest in forest on remote mounds.
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