Dr. Lawrence Ramsden
Honorary Assistant Professor
School of Biological Sciences
Research Areas
Research Areas
Tropical Root & Tuber Crops
Polysaccharides Interactions
Pollination and Breeding Systems of
Hong Kong Trees
Physiology
of Tropical Lianas
Red Leaf Flushing in
Tropical
Trees
Teaching
Broadening
Courses
Other Links
Memoirs of the Hong Kong Natural
History Society
Plover Cove, Hong Kong
Polysaccharide performance is examined for impact on functional
properties in different food systems ranging from low temperature
freeze/thaw behaviour of composite gels to the effects in high
temperature expanded snack products.
The red
cotton tree
Bombax ceiba
is a conspicuous roadside tree in Hong Kong and the large red flowers
borne
before leaf emergence are a classic example of ornithophily, though
some
mammals can also act as pollinators and local squirrels are flower
visitors.
The tree has economic importance from the production of large fibre
filled
capsules which contain the seeds. The fibres are used locally as
stuffing
and padding materials. The floral biology, breeding system and fruiting
of this tree are currently being studied.
Bauhinias
in
Hong Kong are the subject of a project on the breeding system and
taxonomy
of the genera. There are 5 native and 5 introduced species of Bauhinia
in Hong Kong including trees, shrubs and creepers. Further details of
this
project and related information about Hong Kong Bauhinias can be found
at the Hong
Kong
Bauhinia website together with details of the search for seeds of Bauhinia
blakeana in association with local schools.
Forest dynamics; photosynthetic light responses in climbers and trees.
Climbers (vines, creepers or lianas) show a different approach to resource exploitation which contrasts with that adopted by trees but appear highy successful in colonising a range of habitats. In Hong Kong creepers are often the dominant vegetation form on hillsides and act as effective pioneers. This project is examining the physiology of photosynthesis in liana species to assess the adaptation of climbers occupying different habitats.
Red
leaf flushing & photosynthesis in tropical trees.
Why are young leaves red? Many tropical trees produce young leaves
that
are red in colour, this is particularly noticeable in species which
flush
synchronously, that is they produce lots of young leaves at once. As
the
leaves mature they turn green as chlorophyll is synthesised and the red
pigments decay. Since the red colour requires specific synthesis of the
red anthocyanin pigments it would appear to confer some advantage on
the
plant.
Currently there are two main theories:
1) that the red
colour can render the young leaves less visible to herbivores and help
protect young leaves from predation (red crypsis theory).
Many of the above projects are supported by the use of the facilities for cultivation at the Kadoorie Agricultural Research Centre in the Lam Tsuen valley , New Territories, HK.