Pollen-rain-vegetation relationships along a forest-savanna transect in southeastern Cameroon.

TLDR: Modern soil and litter samples from southeastern Cameroon, collected along a continuous forest-savanna transect, were analysed for pollen content to define modern pollen-vegetation relationships and defined inside the forest ecosystem more successional vegetation communities than the botanical surveys allowed.

About: This article is published in Review of Palaeobotany and Palynology.The article was published on 2000-07-01 and is currently open access. It has received 57 citations till now. The article focuses on the topics: Pollen & Basal area.

Figures

Fig. 2. Simplified diagram of modern pollen spectra from the Kandara area, southeastern Cameroon. The pollen sum includes all identified taxa, excluding damaged grains.

Fig. 5. Pollen taxa richness in the modern pollen spectra from the Kandara area, southeastern Cameroon, related to the pollen sum.

Fig. 3. Synthetic diagram of modern pollen spectra from the Kandara area, southeastern Cameroon, showing the main groups of taxa lumped according to the physiognomy of the producing plants.

Fig. 6. Subdivisions along transect 7 in the Kandara area based on floristic inventories (left) and pollen rain analysis (right). Note that forest communities are classified with more detail when pollen rain data are used.

Fig. 4. Comparison between percentages of AP and LAI and basal area [from Youta Happi (1998)] measurements along transect 7 in the Kandara area, southeastern Cameroon.

Fig. 1. (a) Location map of the Kandara area in Cameroon; (b) meteorological data registered at the Bertoua station [from Walter and Lieth (1960)]; (c) location of the transect 7 in the Kandara area and main vegetational communities [1: Rinorea forest; 2: Albizia forest; 3: Raphia swamp; 4: Albizia

Frequently asked questions

Q1. What are the contributions mentioned in the paper "Pollen-rain-vegetation relationships along a forest-savanna transect in southeastern cameroon" ?

The pollen data in the area studied reflected well the recent transgression of forest versus savanna. This permitted us to define inside the forest ecosystem more successional vegetation communities than the botanical surveys allowed. 

Q2. What are the future works in "Pollen-rain-vegetation relationships along a forest-savanna transect in southeastern cameroon" ?

However, in this study the authors propose to define and/or redefine these subdivisions in order that they can be used in the future for palaeoenvironmental reconstructions in the Kandara area. 

Q3. What is the main characteristic of this zone?

The main characteristic of this zone is the occurrence of Sterculiaceae belonging to the species Mansonia altissima-type and Triplochiton scleroxylon-type. 

Q4. What are the common species of plants in the ecotone?

These plants are generally considered as markers of humid and/or swampy formations, but some genera or species can also be found in open grasslands (Kornas, 1993). 

Q5. What species of trees are found in the savanna plots?

In the savanna plots, some forest AP grains (i.e. Myrianthus-type arboreus, Tetrorchidium, Mansonia altissima-type, etc.) supplied by wind are found, but they never reached significant frequencies (<1%), except for Celtis. 

Q6. What is the main taxon of the irvingia type?

Irvingiaceae (Irvingia-type gabonensis including Desbordesia and Klainedoxa) and Petersianthus-type macrocarpus (including Barringtonia racemosa) are also present but in low percentages. 

Q7. What is the main taxon of Alchornea?

The main taxon is Alchornea (>10%) associated with some Bridelia ferruginea-type (including Bridelia micrantha) and Macaranga-type. 

Q8. Where is the lowest diversity in pollen taxa?

The lowest diversity in pollen taxa (<26) is always found at sites in open formations, such as the savanna and the youngest part of the ecotone, but also locally in the Raphia swamp.