Cactus and aloes in Almeria, Spain

Source: Spectrum Colour Library


INTRODUCTION

The Earth's genes, species, and ecosystems are the product of over 3000 million years of evolution, and are the basis for the survival of our own species. Biological diversity (often shortened to 'biodiversity') is a measure of the variation in genes, species and ecosystems. It is valuable because:

Chapter 9 attempts to give a first broad assessment of nature and wildlife on a pan-European scale by examining the state and distribution of ecosystems and species.

A large variety of European landscapes, described in Chapter 8, forms the ecological base for a number of semi-natural habitats for many species of flora and fauna. By encompassing also many important natural habitats (relatively untouched areas), European ecosystems are composed of more than 2500 habitat types (according to the CORINE Habitat Classification) (CEC, 1991) and include about 215 000 species, of which more than 90 per cent are invertebrates (animals without backbones).

Worldwide, about 1.4 million living species of all kinds of organisms have already been scientifically catalogued, but it is estimated that the actual number might be 20 to 30 times higher. Of the 1.4 million classified thus far, approximately 750 000 are insects, 40 000 are vertebrates and 250 000 are vascular plants and bryophytes (eg, mosses) (Parker, 1982). The remainder consists of a complex array of invertebrates, fungi, algae and microorganisms. Each species is the repository of an immense amount of genetic information. The number of genes range from about 1000 in bacteria and 10 000 in some fungi to 400 000 or more in many flowering plants and also in some animals (Hinegardner, 1976).

Although Europe appears to feature a rather modest range of flora and fauna, biodiversity is not defined by number alone. Each biogeographic region of the world has a different and typical set of environmental conditions and its own equilibrium or optimum. Hence, for example, it is impossible to base qualitative assessment of an oligotrophic bog in Ireland on the number of species: this highly specialised habitat is naturally poor in species, and species richness would indicate the presence of a 'sub-optimal' habitat condition probably due to eutrophication.

This example illustrates that biodiversity cannot be understood soley by comparing species; the 'optimal' state of individual habitats and their naturally occurring species must also be taken into account. Such a definition makes biodiversity as much a crucial principle of oligotrophic bogs as of tropical rainforests.

Within Europe, the distribution of species and ecosystems is widely variable, with the least richness found in the far north. Centres of biodiversity are found in the Mediterranean basin and on the margins of Europe in the Caucasus Mountains (Ukraine, Georgia, Armenia), with about 5000 plants being endemic to individual countries. Almost every European country has endemic species (that is, species found nowhere else), but many other species are found in more than one country and require international cooperation for their conservation. Since many of the domesticated plants of Europe originated in countries other than those where they are cultivated today, the genetic material that would be most useful in improving their characteristics is also found in other countries or even in other continents. This indicates the critical importance of developing productive links between and among countries.

GENETIC DIVERSITY

The number of species and the amount of genetic information in a representative organism constitute only part of the biological diversity on Earth. Each species is made up of many individuals. For example, the 10 000 or so ant species have been estimated to comprise 10 000 million million (1015) living organisms, of which virtually no two members of the same species are genetically identical. At still another level, wide-ranging species consist of multiple breeding populations that display complex patterns of geographic variation in genetic polymorphism. Thus, even if an endangered species is saved from extinction, it may have lost much of its genetic diversity, requiring special efforts to restore the diversity.

Genetic diversity provides the variability within which a species can adapt to changing conditions. While this is important to all species, genetic variability in cultivated and domesticated species has become a significant socio-economic resource. Without the genetic variability which enables plant breeders to develop new varieties, food production in Europe would be far lower than it is at present, and far less able to adapt to the inevitable future environmental changes.

Further, biological resources ­ including genetic resources, organisms or parts of them, populations, or any other biotic component of any ecosystem with actual or potential use to humanity ­ are renewable and with proper management can support human needs indefinitely. These resources, and the diversity of the systems which support them, are therefore the essential foundation for sustainable development.

The emergence of biotechnology presents a certain potential for a productive link between conservation and sustainable utilisation of genetic diversity. Biotechnology can lead to new and improved methods of preservation of plant and animal genetic resources and speeding the evaluation of germ plasm collections for specific traits. Maintenance of a wide genetic base (one of the elements of biodiversity) is essential for providing biotechnology with the necessary resources, including both wild and domestic species. But biotechnology also poses ecological and economic risks that could ultimately undermine their potential contribution to the conservation of biodiversity. The release of genetically engineered organisms into the environment thus deserves the most careful supervision and monitoring (as discussed in Chapter 17).

TRENDS

The available evidence indicates that human activities are eroding biological resources and greatly reducing the planet's biological diversity. Estimating precise rates of loss, or even the current status of species, is challenging because no systematic monitoring system is in place and much of the baseline information is lacking. Few data are available on which genes or species are particularly important in the functioning of ecosystems, so it is difficult to specify the extent to which Europe is suffering from the loss of biological diversity. Since the ecological roles played by many species or populations are still only partly known, the wisest course ­ as recognised at UNCED (Rio de Janeiro, 1992) ­ is to follow the 'precautionary principle' and avoid actions that needlessly reduce biological diversity.

In Europe, the changes that have affected biodiversity over the past decades are closely linked to prevailing economic principles, such as ever increasing rates of production and consumption (the 'consumer lifestyle'). Traditionally, this economic system gives low values to biodiversity and ecological functions such as watershed protection, nutrient cycling, pollution control and soil formation. Being very much a cross-sectorial issue, biodiversity is geographically and functionally linked with many sectors of social, political and economic activities. No single sector can by itself ensure that biological resources are managed to provide sustainable supplies of products; rather, cooperation is required between the various sectors, ranging from research to tourism.

The decline of Europe's biodiversity in many regions (see, eg, Table 9.10 and Figure 9.7) derives mainly from highly intensive, partially industrial forms of agricultural and silvicultural landuse, from an increased fragmentation of remaining natural habitats by infrastructure and urbanisation and the exposure to mass tourism as well as pollution of water and air. Given the projected growth in economic activity (Chapter 2), the rate of loss of biodiversity is far more likely to increase than stabilise.

More generally, it has been estimated that almost 40 per cent of the Earth's net primary terrestrial photosynthetic productivity is now directly consumed, converted or wasted as a result of human activities (Vitousek et al, 1986), and the percentage is likely to be even higher than this for Europe due to the pervasiveness of human influences on this continent.

The evaluation of representative sites in Chapter 9 indicates that all types of European ecosystems are facing severe stresses and are not sufficiently well managed to absorb these stresses (see Figure 29.1). The known effects of these stresses on wildlife as well as reports on various species groups (see also Chapter 9) point to a decline of diversity within ecosystems (loss of habitats), within habitats (loss of species) and among species (loss of species and decline of species abundance).

It might be concluded that major habitat changes and associated losses of biodiversity are the inevitable price paid for progress, as humans become an ever more dominant species. A very considerable body of work in the field of conservation biology over the past several decades has shown that reducing the area of habitat reduces not only the population of each species (and hence its genetic diversity), but also the number of species the habitat can hold. Many species that are not in immediate danger of extinction are suffering from declining populations and declining genetic variability. While some opportunist wild animal species ­ sparrows, pigeons, crows, starlings, hedgehogs ­ may be expanding their ranges and populations in Europe, far more are suffering population decline (see, eg, Figure 29.2). Low populations make species far more vulnerable to in-breeding, disease, habitat alteration and environmental stress.

The genetic variety of many cultivated species is being lost, thereby reducing ability to adapt to environmental change. The remaining gene pools in crops such as apples or wheat amount to only a fraction of the genetic diversity they harboured a few decades ago even though the species themselves are not threatened. If these trends continue, European agriculture will have a far narrower genetic base and potentially this will result in many fewer varieties of fruits and vegetables being on the market. Furthermore, these varieties will be less well adapted to local conditions, requiring larger investments in pesticides and fertilisers to maintain productivity. However, with changing patterns of agriculture in Europe, a remarkable potential opportunity exists to manage land in ways that are designed specifically for conserving biological diversity.

In the past few decades, scientists have significantly increased our understanding of the evolutionary processes that have created the biological diversity on Earth today and the contemporary factors that are leading to its reduction. The economic valuation of living natural resources has advanced greatly, and governments are seeking mechanisms for ensuring that the values of biodiversity are expressed in the cost of living and products. Present trends suggest that such principles are likely to find their way into the economic system, though greater investment in them would bring about faster progress. Greatly increased cooperation among European countries can be expected to help address the problems in a Europe-wide context.

SUSTAINABLE GOALS

To prevent an eventual decline in productivity and quality of life, the European landscape needs to be managed to conserve biodiversity, and biological resources have to be used sustainably. The following elements are needed to ensure this:

STRATEGIES

Given that sustainable use of biological resources is the foundation of sustainable development, several strategic lines can be followed to bring about the goals outlined above:

  1. Improve information on biodiversity. Decisions for planning conservation measures, identifying priorities and formulating management policies need to be based on a careful analysis of the most complete and up-to-date factual information. Baseline information on the status and distribution of landscapes, ecosystems and species that can serve as a benchmark for monitoring is available only for relatively few parts of Europe. Collaboration on a European scale is needed to develop data management standards for information on biodiversity (such as standard lists of species, inventory methods, etc), and jointly to determine the most efficient way to collect the European-wide information required.
  2. Establish mechanisms to determine how the convention on biological diveristy can be most useful to each country and to Europe as a whole. All European countries and the European Community have signed the convention and, although the convention entered into force at the end of 1993, much remains to be done actually to implement it. A first step is to prepare national biodiversity strategies and action plans. Strategic issues to address include: means to regulate access to genetic resources, mechanisms for controlling import and possession of materials obtained contrary to the legislation of the originating country; mechanisms to identify the source of material from which any particular benefit is derived; funding mechanisms, intellectual property rights, and technology to transfer.
  3. Elaborate further and implement the draft Action Plan for European Protected Areas prepared under the auspices of IUCN at Nyköping, Sweden, in June 1993.
  4. Pay more attention to the economics of conserving biodiversity and using biological resources sustainably. In addition to the well-known values of agriculture, fisheries and forestry, the whole range of native species, including the genetic variation within species, makes contributions to agriculture, medicine and industry worth many billions of ECUs per year. Nevertheless, biodiversity tends to be perceived largely in scientific and conservationist terms rather than as a resource and as an economic good. This results partly from the difficulties in providing sufficient socio-economic insight to quantify the benefits of conserving biodiversity. Economics can help demonstrate the importance of biodiversity to human society by assigning values to the full range of goods and services it provides.
  5. Concern for biodiversity needs to go beyond the creation of protected areas and conservation agencies. Given its cross-sectional linkages with almost all aspects of human life, biodiversity cannot be conserved through the artificial exclusion of economic forces. Rather, in the coming years, improvements in conserving biodiversity will increasingly need to come from improved management of land and water outside protected areas, and those sites which are given high levels of legal protection will need to be managed as part of wider landuse programmes. These wider programmes are likely to include diversification of agriculture and cropping strategies, encouragement of the spread of new varieties and non-traditional crops, rationalisation of cropping techniques so as to minimise ecological damage, and strategies for the rehabilitation and diversification of damaged habitats. In all cases, greater effort should be made to ensure that local communities are fully involved in the design and implementation of these measures.
  6. The concept of biodiversity needs to be applied to ecosystems, species and genes (and perhaps even landscapes) over the whole of the European continent. The identification and preservation of the remaining valuable natural and semi-natural areas is of the same importance as the implementation of changes in landuse activities for areas where biodiversity has declined due to human impacts. Measures that point at regeneration, extensification and naturalisation of heavily overused landscapes have important functions for the realisation of biological networks (including corridors, buffer zones, etc) that encompass all biogeographic regions and landscapes of Europe.
  7. Biodiversity needs to become a focus of research at national and European research centres, as a contributor (not an alternative) to practical action. Corporations with an interest in biodiversity, including those involved in biotechnology, pharmaceuticals, agrochemicals, and many other products, should be encouraged to combine forces to support the basic research required as a foundation upon which practical, applied research can be built.