For the first approach the atmosphere of tropical regions it seems to be suitable to quote half-century old words of Prof. K. Domin on so-called “useful flora”: “Flora gave and gives not only the most important food (let us remember, eg cereals!) and spices to man but also starchy tubers, vegetable, fruit and spice of all kinds, provides refreshing, encouraging up to narcotic means from tea, coffee to tobacco, opium, hashish an d cola, further various alcoholic beverages, is an inexhaustible source of drugs and vitamins, gives sugar and other sweeteners, oils of all kind, viz for greasing food, for lightening and for technical purposes, further essential oils, camphor, resins, oleoresins, waxes and rubber. It gives man fantastic choice of wood for building, furniture and tools, further fuelwood, provides various raw materials for spinning mills, makes possible fermentation through its enzymes, gives rich deposits of recent peat and particularly primeval coal etc. Moreover, there are innumerable numbers of ornamental plants because also these plants have to be included into the huge group of useful plants.”
In the context of the modern conception of sustainability (accepted in the UN conference in Rio de Janeiro in 1992), possible major departure from the anthropocentrically emphasized necessity of economic growth based above all on the consumption of non-renewable supplies of resources can bring a substantial change in the direction of mankind to the improvement of life quality and sustainable development with the preferential use of renewable resources.
Unfortunately, a decade after the famous conference, neither a decrease in deforestation in developing countries nor marked starting the implementation stage of concluded arrangements occurred as pertinently mentioned J. Lash, the WRI (World Resources Institute) president on the occasion of the follow-up WSSD (World Summit on Sustainable Development) conference held in Johannesburg, August 2002.
The concept of usefulness
Here, we take the liberty to doubt that it is quite right man as one the species of living nature to use blatantly all what he considers to be suitable and to account himself the lord of land, oceans and universe. According to the philosopher Erazim Kohák, “Man as the shepherd of being has failed catastrophically – he did not cultivate the world but ravaged it markedly. Although mankind was not able to destroy the land it should accept a duty to limit its infinite requirements to avoid self-destruction”.
To clarify possible philosophical variants of a relationship between man and other species or between man and the environment it is suitable to define several basic related terms. The conception of anthropocentrism just related to the fail of man as the “shepherd of being” occurs paradoxically in human history together with the conception of theocentrism which, on the other hand, is characterized by a respect to what transcends man. In this context, this respect also occurred in a hunter-picker for his “bothers-animals” when he killed them for food. The conception of biocentrism is an approach of a species- equitable philosophy. It states that every life shows a value in itself and every being shows its actual meaning because of its existence only because it exists. According to an American forester and ecologist Leopold, the meaning of a wolf is to experience the life of its own species, ie to bear, hunt and die naturally. In connection with the term, harmony is understood as accepting the burden of birth (CALLICOT, 1987) and the comprehension of a struggle for survival as part of the order of life because harmonic life includes simply also elements of fight. According to biocentric value glasses, it is possible to note that an idea on the superiority of man is only an expression of the racism of man to other living (or also lifeless) entities of the surrounding world.
It is necessary to define more precisely the conception of “usefulness value” and to outline potential value criteria. In general, people live in the world of artificial things which are of service meaning (value) only for man. On the other hand, a tree “grows for its life”, a squirrel lives by its own life whereas a table, lamp or writing-desk would be only flotsam and jetsam without the interest of man. The concept of a value means a relational fact which can be differentiated to a and actual value. In terms of the purpose-built value a being or a thing assumes a value in such a ways that it serves for a purpose, thus the purpose-built value entitles requirements of various beings towards the other. A concept of the so-called actual value of existence appears to be an opposite opinion. It states that anything is good because it is the “affectionate creation of God” (see eg KOHÁK, 1998 – pp. 44 and 90). This actual value then expresses a fact that life is related to itself or it is a value for itself and all living entity (every biological entity) tries to protect and preserve its life and to avoid distress and death. General good (well-being) of a biological species can be specified formally as the “chance of an animal /up to a plan/ to experience its life corresponding to its species“.
In this context, a philosophical concept of “ethics” is used in terms of the application of moral principles of two relational units. In the course of the moral evolution of mankind, first the codex of behaviour was elaborated on the following levels: individual –individual, individual – human community (all known cultures) and finally the topical elaboration of relationships between individuals and communities up to the surrounding nature (universe).
In the course of time, ethics underwent just the indicated development from Moses’s decalogue (individual – individual) to legislative and moral codexes of various cultures based on autocracy, theocracy or democracy (individual – community). These codexes regulate above all relationships in the human community connecting a social organization with the role of an individual while ethics dealing with a relationship between man and the surrounding universe (natural resources, animals, Earth) develops only now (LEOPOLD, 1949). In other words, it is just this developing instinct (so-called social instinct) which will be inevitable to preserve hopes for the survival of mankind similarly as primeval animal instincts have been inevitable to survive in wilderness.
The usefulness of tropical plants in an economic and global context
Based on the conception mentioned above it is perhaps evident that Homo sapiens tries (in consequence of inner and outer conditions) to become from the conqueror of a biotic community one of its equal citizens understanding the ethic importance of the existence of other species for functioning the community as a whole. Only after accepting the role of a fair-minded thrifty person taking into account ecological costs man is entitled to calculate species effectiveness or so-called “usefulness”.
From the total huge number of spermatophytes (about 300 thousand species) man commonly uses about 10%, ie 30 thousand species. About 12 000 species are used accidentally (ie 4% of the total number). Of the number, some 5800 species rank among forest and ornamental species, 2500 species belong to foods, 2100 species belong to the group of a technical use and 1600 species are used as feed or for agroreclamation purposes (POSPÍŠIL & HRACHOVÁ, 1989). Seeded and planted agricultural land throughout the world supports about 1200 species of useful plants while mere 250 species fall on main foods and plant raw materials. However, according to authors mentioned above there are only 322 cultivated plant species (sensu stricto) from 78 families. It refers to species which do not occur as wild plants in nature.
At first accidental procedures of the selection of species by ancient farmers changed in more systematic breeding of cultural plants in various gene centres in the course of many centuries (VALÍČEK, 1989). A form of the present use of plants by man shows its history, adventurous moments and infinite and tedious hours in laboratories and herbaria. Nevertheless, it is necessary to emphasize that diversity of plants useful for mankind growing in the warm tropical environment was the cause of their use by ways which surpass traditions of the temperate zone.
The best agroforestry systems in the tropics are mostly those which use local sources. From long-term aspects, they function better bringing more yield and sustainability. They are better socially acceptable and politically useful. They show usually smaller negative impacts on ecosystems as compared with introduced systems developed in other regions under different cultural and natural conditions. The resultant successfulness of any technology is, however, always related to observing methodical procedures, sufficiency of means and their flexible adaptation to the character of conditions (climatic, political, social etc.). Reality of the development and planning of the landscape in developing countries is mostly lead by many other circumstances. Unfortunately, these countries often prefer only short-term solution (CLÜSENER-GODT & SACHS, 1994). Of substantial importance is also the above-mentioned fact of slowly changing up to stagnating psychology of man irrespective of his geopolitical membership. A local farmer as well as a statesman will prefer quite certainly shooting the elephants destroying harvest from human activities limiting the establishment of a national park. Tropical secondary forests can be of a great agroforestry potential for mankind if they are effectively and permanently used. A policy to increase profitability of secondary forests shows theoretically 4 main seemingly simple points (SIPS, 1997): (1) support of markets with secondary forest products, (2) improvement of legislation, (3) economic measures, (4) measures stimulating research.
Recently, so-called “non-timber forest products“ are of increasing economic importance (NTFP – non-timber forest products). It refers, eg to fruits, fibres, rubber sources, resin or substances with medicinal or insecticide potentials. “NTFP” play an important role in national and regional economics. In India, some 30 million people are employed in this sector. In Indonesia (central Java), only wood-carving products represent roughly 75% of the export of craft articles (KOPPELL, 1995). The production of rattan in Indonesia provided a lot of jobs in national scale and its value reached 116 thousand tonnes amounting to USD 1.5 milliard in 1991-93, ie 80% of the world market (HARTOYO, 1997). Unfortunately, exploitation was not carried out using sustainable methods which reflected in the marked decrease of forest resources with the occurrence of rattan palms.