Climate change will disproportionally affect the most genetically diverse lineages of a widespread African tree species.

Global climate change is proceeding at an alarming rate with major ecological and genetic consequences for biodiversity, particularly in drylands. The response of species to climate change may differ between intraspecific genetic groups, with major implications for conservation. We used molecular data from 10 nuclear and two chloroplast genomes to identify phylogeographic groups within 746 individuals from 29 populations of Senegalia senegal, a savannah tree species in sub-Saharan Africa.

Seedling recruitment under isolated trees in a tea plantation provides a template for forest restoration in eastern Africa.

Natural regeneration is less expensive than tree planting, but determining what species will arrive and establish to serve as templates for tropical forest restoration remains poorly investigated in eastern Africa. This study summarises seedling recruitment under 29 isolated legacy trees (14 trees comprised of three exotic species and 15 trees comprised of seven native species) in tea plantations in the East Usambara Mountains, Tanzania. Among the findings were that pioneer recruits were very abundant whereas non-pioneers were disproportionately fewer.

Investigating the direct and indirect effects of forest fragmentation on plant functional diversity.

Ongoing habitat loss and fragmentation alter the functional diversity of forests. Generalising the magnitude of change in functional diversity of fragmented landscapes and its drivers is challenging because of the multiple scales at which landscape fragmentation takes place. Here we propose a multi-scale approach to determine whether fragmentation processes at the local and landscape scales are reducing functional diversity of trees in the East Usambara Mountains, Tanzania.

Analysis of Land Cover Changes in Afromontane Vegetation of Image Forest Reserve, Southern Highlands of Tanzania.

An analysis of land cover changes (LCCs) was done in Image Forest Reserve (IFR) from August to October 2019. Free satellite images for 1990, 2004, and 2018 were downloaded from Landsat 5 (TM) and Landsat 8 (OLI) available through the USGS portal. Ground surveys were conducted using systematically set plots of 20 m × 40 m to identify the existing land cover types and human illegal activities.

A new species in the tree genus Polyceratocarpus (Annonaceae) from the Udzungwa Mountains of Tanzania.

Polyceratocarpus askhambryan-iringae, an endemic tree species of Annonaceae from the Udzungwa Mountains of Tanzania, is described and illustrated. The new species is identified as a member of the genus Polyceratocarpus by the combination of staminate and bisexual flowers, axillary inflorescences, subequal outer and inner petals, and multi-seeded monocarps with pitted seeds. From Polyceratocarpus scheffleri, with which it has previously been confused, it differs in the longer pedicels, smaller and thinner petals, shorter bracts, and by generally smaller, less curved monocarps that have a clear stipe and usually have fewer seeds.

Disperser limitation and recruitment of an endemic African tree in a fragmented landscape.

Forest fragmentation may have positive or negative effects on tropical tree populations. Our earlier study of an endemic African tree, Leptonychia usambarensis (Sterculiaceae), in the East Usambara Mountains of Tanzania, found poorer recruitment of seedlings and juveniles in small fragments compared to continuous forest, and concomitant reduction of seed-dispersal agents and seed dispersal. However, the possibility that other biotic or abiotic consequences of the fragmentation process contribute to diminished recruitment in fragments was left open.

Increasing carbon storage in intact African tropical forests.

The response of terrestrial vegetation to a globally changing environment is central to predictions of future levels of atmospheric carbon dioxide. The role of tropical forests is critical because they are carbon-dense and highly productive. Inventory plots across Amazonia show that old-growth forests have increased in carbon storage over recent decades, but the response of one-third of the world's tropical forests in Africa is largely unknown owing to an absence of spatially extensive observation networks.

Ancistrotanzanine C and related 5,1'- and 7,3'-coupled naphthylisoquinoline alkaloids from Ancistrocladus tanzaniensis.

Three new naphthylisoquinoline alkaloids, the 7,3'-coupled ancistrotanzanine C (6), the 5,1'-coupled O-methylancistrocladinine (7), and the likewise 5,1'-coupled O,N-dimethylancistrocladine (8, previously known only as a partial-synthetic compound), have been isolated from the highland liana Ancistrocladus tanzaniensis, along with the two known 7,3'-coupled naphthylisoquinoline alkaloids ancistrocladidine (4) and ancistrotectorine (5). All of the compounds are S-configured at C-3 and bear an oxygen at C-6, and thus belong to the so-called Ancistrocladaceae type, similar to 1-3 previously isolated from this newly discovered plant species. The structural elucidation was achieved by chemical, spectroscopic, and chiroptical methods.

Ancistrotanzanine A, the first 5,3'-coupled naphthylisoquinoline alkaloid, and two further, 5,8'-linked related compounds from the newly described species Ancistrocladus tanzaniensis.

The first phytochemical investigation of the recently discovered East African liana Ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines A (5) and B (6), and the known compound ancistrotectoriline A (7). Ancistrotazanine A (5) represents a hitherto unprecedented 5,3'-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8'-coupled. The structures of the compounds were determined by spectroscopic, chemical, and chiroptical methods.