title: Expansion dynamics of monospecific, temperate mangroves and sedimentation in two embayments of a barrier-enclosed lagoon, Tauranga harbour, New Zealand

authors: Stokes, Debra J.

subjects: mangrove sedimentation

abstract: In recent years, mangrove expansion has become a coastal management issue in the North Island of New Zealand. Little is known about the spatial evolution and forest structure of temperate mangrove forests in New Zealand or about the associated rates of sedimentation. The extent of mangrove colonization in both a large (Waikareao Estuary) and small (Welcome Bay) embayment within Tauranga Harbour were documented. Forest structure and growth rates were described using tree height, stem density, pneumatophore density, and seedling establishment. Surface elevation changes within mangrove habitat were determined from erosion pin measurements and, on bare intertidal flats, using buried baseplates. Sediment texture and availability was also assessed using sediment traps. Results show that in 1943, mangrove vegetation covered <1% of either embayment, with ongoing expansion resulting in mangrove habitat occupying 9% of Welcome Bay and 6% of Waikareao Estuary in 2003. Mean plant heights were all <1.5 m, with vertical plant growth of 3 cm y−¹ to 7.5 cm y−¹. Pneumatophore densities ranged from  200 per m² to  540 per m², and seedling densities of <1 per m² to 14 per m², with seasonal variation, were documented. Surface elevation changes within mangrove habitat ranged from 0 to +21 mm y−¹, compared with −16 to +15 mm y−¹ on adjacent bare flats. Surface sediment within the mangrove habitat was mostly muddy, whereas bare flats were dominated by fine sand. Sediment-trap results provided accumulation rates of up to 32,000 g m−² mo−¹ on bare flats, and close to 29,000 g m−² mo−¹ within the fringing mangrove vegetation. In this study, mangrove vegetation was found to successfully trap and hold muddy sediments, resulting in increased surface elevation. Rising surface elevation from fine sand deposition is also occurring on bare tidal flats in front of mangrove vegetation at some sites.

text: Expansion dynamics of monospecific, temperate mangroves and sedimentation in two embayments of a barrier-enclosed lagoon, Tauranga harbour, New Zealand In recent years, mangrove expansion has become a coastal management issue in the North Island of New Zealand. Little is known about the spatial evolution and forest structure of temperate mangrove forests in New Zealand or about the associated rates of sedimentation. The extent of mangrove colonization in both a large (Waikareao Estuary) and small (Welcome Bay) embayment within Tauranga Harbour were documented. Forest structure and growth rates were described using tree height, stem density, pneumatophore density, and seedling establishment. Surface elevation changes within mangrove habitat were determined from erosion pin measurements and, on bare intertidal flats, using buried baseplates. Sediment texture and availability was also assessed using sediment traps. Results show that in 1943, mangrove vegetation covered <1% of either embayment, with ongoing expansion resulting in mangrove habitat occupying 9% of Welcome Bay and 6% of Waikareao Estuary in 2003. Mean plant heights were all <1.5 m, with vertical plant growth of 3 cm y−¹ to 7.5 cm y−¹. Pneumatophore densities ranged from  200 per m² to  540 per m², and seedling densities of <1 per m² to 14 per m², with seasonal variation, were documented. Surface elevation changes within mangrove habitat ranged from 0 to +21 mm y−¹, compared with −16 to +15 mm y−¹ on adjacent bare flats. Surface sediment within the mangrove habitat was mostly muddy, whereas bare flats were dominated by fine sand. Sediment-trap results provided accumulation rates of up to 32,000 g m−² mo−¹ on bare flats, and close to 29,000 g m−² mo−¹ within the fringing mangrove vegetation. In this study, mangrove vegetation was found to successfully trap and hold muddy sediments, resulting in increased surface elevation. Rising surface elevation from fine sand deposition is also occurring on bare tidal flats in front of mangrove vegetation at some sites.

year: 2010

title: Book review: Popular culture in a globalised India

authors: Athique, Adrian M.

abstract: The article reviews the book “Popular culture in a globalised India” edited by K. Moti Gokulsing and Wimal Dissanayake.

text: Book review: Popular culture in a globalised India The article reviews the book “Popular culture in a globalised India” edited by K. Moti Gokulsing and Wimal Dissanayake.

year: 2012

title: Closing Plenary

authors: Sawrey, Richard

subjects: Maori

abstract: The closing session of the symposium was a plenary session in which invited speakers were asked to make brief critical and reflective comment on the symposium theme and future directions regarding Māori and Pacific psychologies.

text: Closing Plenary The closing session of the symposium was a plenary session in which invited speakers were asked to make brief critical and reflective comment on the symposium theme and future directions regarding Māori and Pacific psychologies.

year: 2008