History
Governments signed the Convention on Biological Diversity at Rio de Janeiro. They expressed a shared belief that action must be taken to halt the world-wide loss of animal and plant species and genetic resources. At the same time they agreed to draw up national plans and programmes and help each other to implement them. The United Kingdom Biodiversity Action Plan establishes a framework but whether, in the end, we and our children enjoy a country which is richer or poorer in species and habitats depends on all of us. The harmonious and healthy functioning of all the organisms, common and rare, which constitute "life" is the concern of the Biodiversity Convention, and hence of every local the biodiversity action plan.
Importance of Biodiversity
1 Biodiversity is the variety of life forms we see around us. It encompasses the whole range of mammals, birds, reptiles, amphibians, fish, insects and other invertebrates, plants, fungi, and micro-organisms such as protists, bacteria and viruses.
2 Article 2 of the Biodiversity Convention defines biological diversity to mean:-
The variability among living organisms from all sources including, terrestrial, marine and other aquatic ecosystems and includes diversity within species, between species, and between ecosystems.
Biodiversity matters because:-
future practical needs and values are unpredictable and our understanding of ecosystems is insufficient to be certain of the impact of removing any component;
genetic diversity provides the variability within which a species can adapt to changing conditions.
the less diverse environmental systems are, the less likely it is that gene pools and reservoirs, indeed genetic variability of all kinds. will be available to substitute for others that are depleted;
if the effective population size of an organism falls below a certain level. the species is likely to die out;
diverse environmental systems normally enhance the resilience to cope with ecological stresses: many losses are irreversible;
there is considerable uncertainty about the values, including economic values, that future generations may attach to biodiversity: our knowledge is so limited, so it makes sense to preserve as many species as possible, as insurance, since we do not yet know which are potentially useful;
no organism lives in isolation from other living things and each has its own way of life which contributes to the balance of nature. The inter-dependence and successful functioning of all these parts is a key contributory factor to the healthiness of the planet as a whole. If we continue to pollute the atmosphere, contaminate land and water, and degrade our ecosystems by, for example, destroying forests, wetlands and marine environments, then the planet will suffer;
genetic variability in cultivated and domestic species is, and probably always will be, an extremely important social and economic resource. It was genetic variability which enabled early people to develop the crops and livestock which were a pre-requisite of settled agriculture and which now enable breeders to develop new varieties. The continued development and stability of agriculture, especially in the longer term, depend to no small extent on our capacity to continue doing this;
the culture of a nation is closely allied to the biodiversity of its landscapes. The moral argument adds to this perspective the view that we should hand on to the next generation an environment no less rich than the one we ourselves inherited. We believe that a culture which encourages respect for wildlife and landscapes is preferable to one that does not. In other words we conserve species and habitats because they are beautiful or because they otherwise enrich our lives.
Goal and Objectives
The overall goal of the UK Action Plan for Biodiversity is to conserve and enhance biological diversity within the UK and to contribute to the conservation of global biodiversity through all appropriate mechanisms.
Objectives for conserving biodiversity are:-
To conserve and where practicable to enhance:
a) the overall populations and natural ranges of native species and the quality and range of wildlife habitats and ecosystems;
b) internationally important and threatened species, habitats and ecosystems;
c) species, habitats and natural and managed ecosystems that are characteristic of local areas;
d) the biodiversity of natural and semi-natural habitats where this has been diminished over recent past decades.
To increase public awareness of, and involvement in, conserving biodiversity.
To contribute to the conservation of biodiversity on a European and global scale. In global terms, the UK is not particularly rich in species; for example, only 210 of the 9,881 species of birds in the world breed in the UK. Nevertheless it has a rich and characteristic biological diversity for an island of its size, isolation and geographical position. Many aspects of the UK's biodiversity are linked with biodiversity elsewhere, notably in the case of migratory birds, sea mammals and fish. Several species are dependent on a particular character of landscape or of land management. If these change, species can suffer.
Even Common Species are at Risk
Many bird species typical of lowland farmland such as the grey partridge, barn owl and lapwing have undergone pronounced declines since the mid 1970s. Housemartins and skylarks are not so common as they were 10 years ago. These trends coincided with major changes in agricultural practices in lowland Britain such as the switch from spring to autumn sowing of arable crops and a move away from crop rotations and mixed farming.
An analysis of changes in plant species richness surveyed in 1978 and 1990 was included in the Countryside Survey 90. In 1978 over 1,000 vegetation plots were located at random within a sample of 256 1 km squares representative of Great Britain. The same plots were re-surveyed in 1990. For all plots surveyed in both 1978 and 1990, regardless of whether the plots remained in the same broad habitat type, there were significant losses of species richness in semi-improved grassland (-13%), woodland (-14%) and upland grass mosaics (- 11%). There was a gain in richness in moorland habitats (+7%).
For the plots that remained within the same habitat type in 1978 and 1990 there were significant losses of richness in arable fields (-2 9%) and woodlands (-20%), and a gain in diversity in moorland habitats (+8%). Between 1984 and 1990, there was a net loss of 23% of hedges (about 130,000km) in Great Britain. The net loss of hedges was the result of a combination of hedge removal and hedge degradation, and it occurred despite the planting/regeneration of about 5 0,000km of hedges. In addition to the reduction in the extent of this important linear habitat, there is also a loss of quality. Between 1978 and 1990, on average one plant species was lost from each 10 metres of hedge, an 8% loss of plant species richness.
Checking on biodiversity is not just about the rarities. A change in the abundance of a place, weeds may be a local indicator of a more widespread disaster.
Concerns
1 Our concerns about losses of habitats and species can be grouped into the following categories: -
the continuing loss and fragmentation of habitats such as chalk grassland, heather moorland, hay meadows and wetlands, as a result of such factors as intensified farming practices, abstraction of water and development and road construction;
the loss of habitats, linear features such as hedgerows, field margins and ditches, and their associated species resulting from neglect or abandonment, and from the decline of traditional forms of management as they become increasingly uneconomic and difficult to sustain;
point source or diffuse pollution arising from a variety of sources including effluent from sewerage treatment works and industrial processes, run-off from agricultural chemicals or farm waste and acid deposition as a result of burning fossil fuels.
Any one of these concerns could be the stimulus for a local bioscope. There is also a need for making simple inventories of common wildlife which provide a baseline for checking in future years. Here is an example of the importance of school records. Children in Northamptonshire during the 1950s recorded the
Chequered skipper butterfly as 'common in most local woods'. Photographs were taken of it at that time. Now it is extinct in England. The reasons for its disappearance are not known. A rigorous annual survey might have generated alarm and efforts made to conserve it.