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DIY New Zealand

Manawatu Estuary Trust

Last updated:
September 2010


Jill Rapson: Current research topics

Exotic invaders: predicting potential future superweeds

Calluna vulgaris (European heather) and Pinus contorta (lodgepole pine) invading Chionochloa rubra tussock grassland, Tongariro National Park.New Zealand is unusually vulnerable to invasion by exotic plant species. Ken Thompson of the University of Sheffield, England, and I are investigating this situation using database studies of English cities to look at how invasive these are. Since many European species are also present in New Zealand, this helps to understand the local situation. A similar database covering major temperate urban cities is also under way. A recent publication on the subject of urban floras used databases from Europe to explore homogenisation of floras, and a follow-up paper on phylogenetic constraints in urban flora assembly has just been submitted..

Here at home, the flora of urban areas of the lower North Island was recently studied by sabbatical visitor Ulle Asmus of Germany, during which species new to this country were discovered. There is still much to learn about the effects of factors such as population density, traffic routes, railways, and waste areas on our urban flora. Often the initial invasion site for new arrivals, the role of urban areas as invasion facilitators is unknown, though new invaders usually expand from urban areas into conservation estate.

Publications on exotic invaders:

La Sorte, FA; McKinney, ML; Pyšek P; Klotz, S; Rapson, GL; Celesti-Grapow, L; Thompson, K (2008). Distance decay of similarity among European urban floras: the impact of non-native species on spatial patterns of diversity. Global Ecology and Biogeography, 17, 363-371. (Link)

Asmus, U; Rapson, GL Rapson (2008). Die Trittpflanzen-Gemeinschaften in den südlichen Städten der Nordinsel Neuseelands. Braunschweiger Geobotanische Arbeiten, 9, 43-54. (Link)

Costall, JA; Carter, RJ; Shimada, Y; Anthony, D; Rapson, GL (2006). The endemic tree Corynocarpus laevigatus (karaka) as a weedy invader in forest remnants of southern North Island, New Zealand. New Zealand Journal of Botany, 44, 5-22.

van Essen, RA; Rapson, GL (2005). Fruit size of karaka (Corynocarpus laevigatus) in relation to potential selection by Maori. New Zealand Botanical Society Newsletter, 81, 13-16.

Page, B; Betteridge, K; McGregor, PG; Rapson, GL; Costall, DA (2001). Effect of plant condition on oviposition by ragwort flea beetle. New Zealand Plant Protection, 54, 116-119.

Wilson, JB; Rapson, GL (1995). The genetics of naturalization: A comparison of morphological variation within and between populations of Agrostis capillaris L. as an exotic in New Zealand and as a native in Britain. New Zealand Journal of Ecology, 19, 195-202. (Link)

Rapson, GL; Wilson, JB (1992). Genecology of Agrostis capillaris L. (Poaceae) -- an invader into New Zealand. 1. Floral phenology. New Zealand Journal of Botany, 30, 1-11. (Link)

Rapson, GL; Wilson, JB (1992). Genecology of Agrostis capillaris L. (Poaceae) -- an invader into New Zealand. 2. Responses to light, soil fertility, and water availability. New Zealand Journal of Botany, 30, 13-24. (Link)

Wilson, JB; Rapson, GL; Sykes, MT; Watkins, AJ; Williams, PA (1992). Distribution and climatic correlations of some exotic species along roadsides in South Island, New Zealand. Journal of Biogeography, 19, 183-193. (Link)

Rapson, GL; Wilson, JB (1988). Non-adaptation in Agrostis capillaris L. (Poaceae). Functional Ecology, 2, 479-490. (Link)

Wilson, JB; Hubbard, JCE; Rapson, GL (1988). A comparison of realised niche relations of species in New Zealand and Britain. Oecologia, 76, 106-110. (Link)

Rapson, GL (1985). Vegetative strategy in Agrostis capillaris L. Ph.D. Thesis. Otago University, Dunedin, New Zealand.

Coastal and dune vegetation

Castlepoint, home of the Castlepoint tree daisy, Brachyglottis compacta.New Zealand has a huge coastline for its size, but relatively few fragments of native duneland vegetation survive. Students have looked at the vegetation patterns of some important remnants throughout the country, including dune wetlands with their interesting dynamics and unique conservation problems. A number of rare species occur on dunes, and one, Pimelea arenaria, has been a recent focus, but other species, including locally endemic plants are poorly known. Several interesting dune areas await study, as well as increasingly rare dune species, such as our major native sand binder. I am also keen to investigate the impact of habitat management techniques in dunelands.

Publications on coastal and dune vegetation:

Dawson, PAC; Rapson, GL; Robertson, AW; Fordham, RA (2005). Limitations on recruitment of the rare sand daphne Pimelea arenaria (Thymelaeaceae), lower North Island, New Zealand. New Zealand Journal of Botany, 43, 619-630.

Pegman, APM; Rapson, GL (2005). Plant succession and dune dynamics on actively prograding dunes, Whatipu Beach, northern New Zealand. New Zealand Journal of Botany, 43, 223-244.

Walker, S; Wilson, JB; Steel, JB; Rapson, GL; Smith, B; King, WM; Cottam, YH (2003). Properties of ecotones: Evidence from five ecotones objectively determined from a coastal vegetation gradient. Journal of Vegetation Science, 14, 579-590. (Link)

Wilson, JB; Watkins, AJ; Rapson, GL; Bannister, P (1993). New Zealand machair vegetation. Journal of Vegetation Science, 4, 655-660. (Link)

Strings, fens, carrs, domes and aapamires

Sampling from a montane wetland as part of an experiment into competition.Wetlands (both bog and swamp types, with their associated range of local names) are environments undergoing much destruction in New Zealand, despite their important contributions to supply of ecosystem services. I have been involved in attempting to understand wetland patterns, and to isolate causes of pattern formation (patterns of ponds and hummocks) in peat-based wetlands. A student is currently investigating the competitive balance between two common wetland species, one of which appears to be driving change towards peat-accumulating systems. Future work could review the habitat, and ecologies of native macrophyte species, and their role in water quality, as well as studies of more nutrient-poor mires.

Publications on strings, fens, carrs, domes and aapamires:

Rapson, GL; Sykes, MT; Lee, WG; Hewitt, AE; Agnew, ADQ; Wilson, JB (2006). Subalpine gully-head ribbon fens of the Lammerlaw and Lammermoor Ranges, Otago, New Zealand. New Zealand Journal of Botany, 44, 351-375.

Walker, S; Steel, JB; Rapson, GL; Roxburgh, SH; King, WM; Watkins, AJ; Myers, TE; Keogh, JA; McQueen, AAM; Wilson, JB (2001). A Chionochloa / Sphagnum / cushion valley bog in East Otago, New Zealand. New Zealand Journal of Ecology, 25, 39-52. (Link)

Agnew, ADQ; Rapson, GL; Sykes, MT; Wilson, JB (1993). The functional ecology of Empodisma minus (Hook. f.) Johnson & Cutler in New Zealand ombrotrophic mires. New Phytologist, 124, 703-710. (Link)

Carpet of Racomitrium pruinosum surrounding bog pine, Halocarpus bidwillii, Wilderness Reserve, Te Anau.General vegetation

Student exercises, contracts, and novel post-grad research topics generate a stream of papers in wide-ranging topics relevant to vegetaion science. Most focus on vegetation responses to environmental change or imposed environmental stresses.

Publications on general vegetation:

Li, X; Rapson, GL; Flenley, JR (2008) Holocene vegetational and climatic history, Sponge Swamp, Haast, south-western New Zealand. Quaternary International, 184, 129–138. (Link)

Adamson, R; Braaksma, H; Brill, S; Dove, K; Ogle, L; McKenzie, K; McVeagh, J; van Essen, RA; Rapson, GL (2004). Factors affecting vegetation of the Hawdon River alluvial outwash fan, Arthur’s Pass, New Zealand. Canterbury Botanical Society Newsletter, 38, 58-69.

Pyšek, P; Prach, K; Joyce, CB; Mucina, L; Rapson, GL; Müllerová, J (eds) (2001). The role of vegetation succession in ecosystem restoration. Applied Vegetation Science, 4, 1-114.

Garner, S; Horton, P; Olliff, M; Rapson, GL; Urlich, M (1999). Great Barrier Island and Coromandel Peninsula: A report on the inclusion of Great Barrier Island and Coromandel Peninsula in a new National Park, based on their botanical attributes. Report to Department of Conservation, Auckland, Thames, Wellington. 43pp.

Nicholls, VJ; Rapson, GL (1999). Biomass allocation in subantarctic island megaherbs, Pleurophyllum speciosum (Asteraceae) and Anisotome latifolia (Apiaceae). New Zealand Journal of Ecology, 23, 87-93. (Link)

Rapson, GL; Severinsen, M; White, A (1998). Demography of treeline mountain beech as a guide to lahar events. Conservation Advisory Notes no. 210. Department of Conservation, Wellington. 15 pp.

Rapson, GL; Severinsen, M; White, A (1997). Demography of treeline mountain beech as a guide to lahar events affecting the Whakapapaiti Hut, Tongariro National Park. Report to Department of Conservation, Turangi. 11 pp. Also appearing as Conservation Advisory Science Notes 210 (1998), 15 pp.

Rapson, GL; Thompson, K; Hodgson, JG (1997). The humped relationship between species richness and biomass - testing its sensitivity to sample quadrat size. Journal of Ecology, 85, 99-100. (Link)

Matthew, C; Hofmann, A; Rapson, GL; McKenzie, RL; Kemp, PD; Osborne, MA (1996). Growth of ryegrass and white clover under canopies with contrasting transmission of ultraviolet-B radiation. Proceedings of the Agronomy Society of New Zealand, 26, 23-30.

Rapson, GL (1995). Impacts of tree coring on mountain beech health near treeline, Turoa. Report to Department of Conservation, Turangi. 6pp.

Rapson, GL; Cole, A; Blackwell, G; Cottam, Y; Flannagan, H; Glover, L (1994). Vegetation change in permanent monitoring sites on Manganui Skifield and adjacent Ngarara Bluffs, Mt Taranaki, Egmont National Park, New Zealand. Report to Department of Conservation, Stratford. 27 pp.

Rapson, GL; Maze, J (1994). Variation and integration in the rare grass Achnatherum (Oryzopsis) hendersonii: phenotypic comparison with parapatric common congeners. Canadian Journal of Botany, 72, 693-700.

Rapson, GL; Flenley, JR (1993). The possible impacts of increased UVB radiation on New Zealand forests. In: UV radiation and its effects. Proceedings of the National Science Strategy Committee for Climate Change Workshop, International Antarctic Centre, Christchurch, 20-21 May 1993. Royal Society of New Zealand, Wellington. p.17-19.

Other publications

Rapson, GL (2004). Obituary: Ella Orr Campbell, DipTch, MA(Hons), DSc, DNZM, 1910-2003. New Zealand Journal of Botany, 42, 695-708. (Link)

Rapson, GL (1998). Soil nutrient analysis - Costs, protocols and problems. Report to Department of Conservation, Turangi. 6 pp.

Rapson, GL (1995). Style guide for authors. New Zealand Journal of Ecology, 19, 235-244.

Rapson, GL; Rapson, LJ; Hanna, JE; McArthur, CD (1993). General index 1953-1993 for Proceedings of the New Zealand Ecological Society, Vols. 1-24, and New Zealand Journal of Ecology, Vols. 1-17. New Zealand Journal of Ecology, 17, 117-205.