Applied Ethnobotany: People, Wild Plant Use and Conservation \( PDFDrive.com \).mobi by A. B. Cunningham

Author:A. B. Cunningham [Cunningham, A. B.]
Language: eng
Format: mobi
Tags: Earthscan Publications Ltd.
ISBN: 1853836974
Published: 2021-04-14T23:49:06.981588+00:00

Applied Ethnobotany 20/11 04/12/2000 05:28 pm Page 150

Applied Ethnobotany

mation’ of plant species where there is a

concerned with these issues may prefer to

high or low opportunity for sustainable

go directly to the next section: ‘Costs and

harvest. The next sections describe the

Complexity: Inventory, Management and

theoretical background to some of these

Monitoring’.

‘filters’. Readers who are not directly

Bridging gaps in knowledge: life forms, plant architecture and reproductive strategies

Developing an ecological perspective that

light requirements, such as shade-tolerant

cuts across taxonomic boundaries at a

versus light-demanding species, or ‘gap’

species level is a useful tool for grouping

versus ‘non-gap’ species. As you walk

harvested plant species and setting priori-

through grassland, savanna or along a

ties for detailed studies of density, yield or

forest trail, coming out of deep shade and

harvesting impacts. In almost any society,

dappled light into sun-filled gaps edged

people classify plants according to their

with vines and large-leaved shrubs and

growth form – for example, as trees,

young trees, it is a useful exercise to think

shrubs, vines, lianas, epiphytes or grasses.

about how the plant species you see fit

For centuries, botanists and ecologists

into these categories and how different

have developed classification systems

‘guilds’ of species are influenced by distur-

based on plant attributes that group plants

bance, such as fire, drought, disease, tree

into different categories. Several of these

falls or clearing of habitat.

may already be familiar to you, such as

These classifications get away from the

plant life form (Raunkiaer, 1934), plant

detail of species-level identifications and

architecture (Hallé and Oldeman, 1970),

enable plants to be sorted into functional

leaf characteristics (Reich et al, 1992),

ecological groups; they give a better

reproductive strategies (reseeders versus

insight into plant population dynamics

resprouters) or seed characteristics (ortho-

and improve our ability to predict the

dox versus ‘recalcitrant’ seeds) In forests,

impact of harvesting. For this reason, they

it is possible to identify ‘guilds’ of plants

are described here for field researchers

based on successional stage (early pioneer,

who want background information on

late secondary, primary forest species), or

why these ‘ecological filters’ are useful.

to group plant species according to their

Plant life forms

In the early 1900s, the Danish botanist

and whether plants were found in water

Christian Raunkiaer categorized plants

or on land). Raunkiaer also took into

into ‘life forms’ (Raunkiaer, 1934). This

account the form and location of the buds

widely accepted classification system

or storage structures, such as bulbs, corms,

grouped different vascular plants accord-

rhizomes or tubers, which enable peren-

ing to the height of mature individuals, the

nial plant species to persist from one

type of shoot systems (such as woody or

season to the next. Although he used

herbaceous, climbing or self-supporting,

rather cumbersome names for different life

150

Applied Ethnobotany 20/11 04/12/2000 05:33 pm Page 151

Opportunities and Constraints on Sustainable Harvest: Plant Populations forms, thinking about plants in terms of

•

Plant species are chosen whose archi-

life-form categories is useful in establish-

tecture and rhythmic growth patterns

ing basic resource-management principles,

enable age estimates in a range of very

since these represent a sequence from large

different plant families, such as those

trees (‘mega-phanerophytes’) and shrubs

in ‘Corner’s model’ – for instance,

(‘micro-phanerophytes’) through to

palms, tree ferns and grass trees

annual herbs (‘therophytes’). This helps to

(Xanthorrhoeaceae), whose architec-

bridge the gap in knowledge about plant

ture lends itself to field assessments of

population dynamics, enabling a first

leaf production and leaf harvesting

approximation of categories of vulnerabil-

rates, assessments of how stem harvest-

ity to destructive harvesting.

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