BS 55 11 Documenting plant diversity in Central French Guiana: The first step toward understanding biocomplexity SCOTT A. MORI, CAROL A. GRACIE, EDMUND F. HECKLAU, TATYANA A. LOBOVA, AMY BERKOV AND JEAN-JACQUES DE GRANVILLE MORI, S.A., GRACIE, C.A., HECKLAU, E.F., LOBOVA, T.A., BERKOV, A. & DE GRANVILLE, J.J. 2005. Docu- menting plant diversity in Central French Guiana: The first step toward understanding biocom- plexity. Biol. Skr. 55: 11-24. ISSN 0366-3612. ISBN 87-7304-304-4. Publication of the Guide to the Vascular Plants of Central French Guiana completes the first phase of a botanical inventory of central French Guiana. This floristic effort has stimulated studies of pol- lination biology, insect predation, forest ecology, and seed dispersal; and has promoted conserva- tion and ecotourism. We provide examples of 1) bee pollination of species of Corythophora (Brazil nut family, Lecythidaceae); 2) attack of the wood of Lecythidaceae by species of cerambycid bee- tles; 3) life form, habitat, and nutritional mode composition of the species of the flora; 4) the importance of bats as dispersers of seeds; 5) use of plant diversity data in promoting conserva- tion; and 6) ecotourism and how it can increase local income without damaging forest diversity and structure. We conclude that floristic inventories act as a catalyst for studies in many other dis- ciplines and, as such, are the first step in understanding biocomplexity. Scott A. Mori, Institute of Systematic Botany, The New York Botanical Garden, Bronx, New York 10458- 5126, USA. Carol A. Gracie, Institute of Systematic Botany, The New York Botanical Garden, Bronx, New York 10458- 5126, USA. Edmund F. Hecklau, Institute of Systematic Botany, The New York Botanical Garden, Bronx, New York 10458-5126, USA. Tatyana A. Lobova, Institute of Systematic Botany, The New York Botanical Garden, Bronx, New York 10458-5126, USA. Amy Berkov, Department of Biology, Marshak J526, City College of New York, Convent Avenue at 138th Street, New York, New York 10031, USA. Jean-Jacques de Granville, Herbier de Guyane, Institut de Recherche pour le Développement, Boite Postale 165, 97323 Cayenne Cédex, France. Introduction naeus (1775). Moreover, there have been and The plants of the Guianas have been collected continue to be long-term floristic projects such and studied since the latter part of the 18th cen- as the Flora of Suriname, The Flora of the Guianas tury beginning with Aublet (1775) and Lin- (Lindeman & Mori 1989), and the Checklist of 12 BS 55 the Plants of the Guianas (Boggan et al. 1997). As possible because of our floristic inventory. The a result, the plants of this part of South Amer- Flora of Barro Colorado Island (Croat 1978) and ica are among the best known of all of the the subsequent studies (Leigh et al. 1996) that American tropics. Nevertheless, there is still a have been stimulated by it serve as a model for great deal that needs to be done to complete what we are attempting to accomplish in cen- the inventory and as well as to understand the tral French Guiana. biocomplexity of Guianan ecosystems. As examples of the kinds of studies pro- As part of the effort to document the flora of moted by knowledge of the flora, we will dis- the Guianas, The New York Botanical Garden cuss (1) the pollination of Lecythidaceae, (2) (NY) and the Institut de Recherche pour le the attack of the wood of species of Lecythi- Développement – Cayenne (IRD-CAY) have daceae by cerambycid beetles, (3) the life been engaged in a project called the Guide to forms, habitats, and nutritional modes of the the Vascular Plants of Central French Guiana since flowering plants of central French Guiana, (4) 1976. Our goals are to: the importance of bats as dispersers of the – document with herbarium collections the fruits of Cecropia, (5) ecotourism and how it species of plants found in an area sur- can stimulate local economies without destroy- rounding the village of Saül in central ing biological diversity, and (6) knowledge of French Guiana (Mori et al. 2002b), plants and how it can be used to make argu- – furnish keys and descriptions, including ments for conservation. Additional informa- photos and botanical line drawings, to tion about our program of research in central facilitate the identification of plants (Mori French Guiana can be found at Fungal and et al. 1997, 2002a), Plant Diversity of Central French Guiana and – promote studies of ecology, systematics, Bat/Plant Interactions in the Neotropics at: evolution, and conservation by providing www.nybg.org/bsci/french_guiana others with the ability to identify plants and included in their studies, www.botanypages.org – encourage ecotourism as a way to gener- ate income without destroying the forest, and Study area – supply data for conservation. The area of our study includes 1402.5 square With the publication of the Guide to the Vascular km (140250 hectares) covered mostly by undis- Plants of Central French Guiana (Mori et al. 1997, turbed, non-flooded forest between 200 m and 2002a), we have accomplished goals one 400 m elevation (Mori & Boom 1987; Oldeman through three. As a result of these efforts, con- 1974). It encompasses a rectangle in the geo- siderable progress had been made in the other graphic center of French Guiana between goals as well. In addition, the recent publica- 3°30’ and 3°45’ N latitudes and 53° and tion on the mosses of central French Guiana 53°28’W longitudes (Fig. 1). The most obvious has expanded the inventory to the non-vascu- deviations from the predominant vegetation lar plants (Buck 2003). pattern are found in poorly drained areas The steps we followed to gather the collec- often dominated by Euterpe oleracea Mart. (Are- tions, write, and publish the Guide are caceae); on outcroppings of large, granitic described elsewhere (Mori & Gracie in review). rocks, i.e. inselbergs (de Granville & Sastre Therefore, the purpose of this paper is to 1991), which occur as steep slopes surrounded describe the kinds of studies that have been by forests of varying height as at Pic Matécho; BS 55 13 Fig. 1. Location of the study area. A. In relation to South America and French Guiana. B. The area covered by the Guide to the Vascular Plants of Central French Guiana (Mori et al. 1997). 14 BS 55 Fig. 2. Documenting plant diversity in central French Guiana. Left columns: Accu- mulation of vascular plant species recorded in central French Guiana over time. Right columns: Decrease in the number of specimens gathered; the number of specimen decreases as the flora of central French Guiana becomes better known. and in limited areas of secondary vegetation Sandwith (Bignoniaceae). There are no large found near the village of Saül and at scattered areas of white sand and seasonally flooded homestead sites. In addition, the zone extend- ground and hence the associated vegetation ing from 500 m to the highest peak on Mont types are lacking in central French Guiana. Galbao (762 m) consists of cloud forest. The Annual rainfall for central French Guiana, as study site does not contain any large lakes or recorded in the village of Saül, averages 2413 rivers, but many small streams are present mm. There is a well defined dry season from throughout the area. A small lake caused by July to November and a less pronounced and impeded stream drainage near Pic Matécho is less reliable dry period for several weeks in home to species so far found nowhere else in February to March. Under the influence of NE the area, e.g., Mayaca sellowiana Kunth (Maya- or SE trade winds of moderate velocity (aver- caceae), Nymphaea glandulifera Rothschied age 1,6 m/sec), temperatures vary only slightly (Nymphaeaceae), and Tabebuia insignis (Miq.) through the year, averaging 27.1° C (Mori & BS 55 15 Prance 1987). The difference between the dle and to archive, but which add little to longest and shortest days of the year is approx- botanical knowledge. On the other hand, a low imately 35 min (List 1950). IEBE indicates that not enough specimens are available to provide the information needed to describe all stages of a species’ life cycle as well The Vascular Plant Inventory as its ecological and morphological variation. It is difficult to determine when enough collec- The IEBE value for central French Guiana is tions have been accumulated to justify the pro- 7.0 (total number of collections [13488]/total duction of a Flora. The collection process adds number of species [1918]) suggesting that the taxa new to science, taxa new to the flora, and number of collections per species for this area new information about known taxa. If the goal falls into the lower range of the number of a project is simply to document the species needed for initiating the preparation of the found in a flora by providing a checklist, then Guide. As the size of the area covered by floris- only one collection per species is needed, and tic inventories increases, however, higher IEBE the total number of collections equals the total values are needed to understand the wider geo- number of species in the flora. When our graphic distribution, larger ecological ampli- species accumulation curve (Fig. 2) began to tude, and greater morphological variation level off, we decided that future discovery of characteristic of species over wider areas. species new to the flora would be minimal, and As botanical exploration progresses, the this was one consideration in determining total number of collections per expedition or when writing of the Guide could begin. per period of time should diminish because However, the format of the Guide required the easy-to-collect common species are avoided more information about species than just their as they are already represented by sufficient presence, and this information was obtained by specimens (Fig.