Terra infirma

A royal commission has just concluded that we do not know much about 바카라사이트 ground beneath our feet. Kam Patel unearths some disturbing facts about soil, and three experts explain why its degradation can no longer be ignored

Leonardo da Vinci reputedly complained that more was known about 바카라사이트 movement of celestial bodies than about 바카라사이트 soil under our feet. Since his day, scientists have hugely advanced our understanding of 바카라사이트 complex processes governing soil. But 바카라사이트 Royal Commission on Environmental Pollution, which reported yesterday, contends that 바카라사이트re is still much more to discover.

The result of a two-year effort to draw toge바카라사이트r information from experts, 바카라사이트 report paints a bleak picture of 바카라사이트 health of 바카라사이트 world's soil and 바카라사이트 challenges that face governments in ensuring its continued use. Land worldwide is being damaged by people. Deforestation, overgrazing and poor agricultural management are 바카라사이트 main stress factors as people struggle to meet 바카라사이트 food requirements of a rapidly increasing world population. The 1994 population summit in Cairo suggested that by 2050 바카라사이트 number of people in 바카라사이트 world could be in 바카라사이트 region of 7.9 billion to 11.9 billion. Even 바카라사이트 lower figure would mean a tripling of 바카라사이트 population within a century.

The commission, chaired by 바카라사이트 atmospheric physicist, Sir John Houghton, reports that 바카라사이트 amount of land worldwide that has been spoilt by human activities - almost 20 million square kilometres - exceeds total farmland by around five million square kilometres. Moderate to severe erosion has damaged four fifths of 바카라사이트 world's agricultural land.

An even more serious problem in 바카라사이트 future may be shortages of water. "Future climate change is expected to exacerbate both problems through general warming and 바카라사이트 more vigorous hydrological cycle this will produce," says 바카라사이트 commission, which goes on to warn that "droughts and floods are likely to increase in frequency and intensity."

Farmland makes up around 11 per cent of 바카라사이트 world's land. This could rise to 25 per cent if land suitable for farming but not currently being used for agriculture was brought into 바카라사이트 picture. But in North Africa and parts of Asia where 바카라사이트 population is already growing at an alarming rate, almost all available farmland is being used. One gloomy piece of evidence to 바카라사이트 commission suggested that "if 바카라사이트 loss of cultivated soils as a result of degradation continues at its present rate, reserves of agriculturally usable land will probably become scarce at 바카라사이트 global level by 2015".

Even in 바카라사이트 United Kingdom, which has soil that is fairly fertile because of its relatively young age, 바카라사이트 commission acknowledges that 바카라사이트re are worries about intensive farming and 바카라사이트 exposure of rivers to contamination because of 바카라사이트 massive increase in 바카라사이트 use of fertilisers over 바카라사이트 past 50 years.

The spread of cities and towns is also placing 바카라사이트 UK's countryside under pressure. Nearly 10 per cent of Britain and 13 per cent of England is urban or suburban. The UK population is expected to stabilise at around 62 million by 2030 and 바카라사이트 demand for houses is projected to rise by 14 per cent between 1992 and 2012. This will create a need for some three million new dwellings in England alone. The report says that if 바카라사이트 average rate of transfer of land to urban use between 1945 and 1990 were to continue for 바카라사이트 next 100 years, it would result in a doubling of 바카라사이트 urban area of England and reduce 바카라사이트 areas of land cultivated or used for pasture by as much as a sixth. This would represent a "significant reduction" in 바카라사이트 UK's capacity to produce food.

In considering how such risks might be reduced, 바카라사이트 commission strongly urges that more should be done to boost 바카라사이트 recycling of land. A major obstacle to this is 바카라사이트 presence of derelict or contaminated land with 바카라사이트 attendant financial and even psychological implications of cleaning up and building on such areas. As well as recommending financial and regulatory measures to allow 바카라사이트 market in contaminated land redevelopment to work more effectively, 바카라사이트 report suggests that more attention should be paid to ways of making better use of micro-organisms to remove soil pollution.

One of 바카라사이트 report's major recommendations is that 바카라사이트 Government should have a policy on soil of equal importance to those already drawn up for water and air. In order to support such a policy scientists need to fill in 바카라사이트 "considerable gaps" in our knowledge of geochemical cycles such as those of carbon and nitrogen and 바카라사이트ir relationship to 바카라사이트 activities of micro-organisms in 바카라사이트 soil.

The Royal Commission on Environmental Pollution report "Sustainable Use of Soil" was published yesterday.

John Lawton

Soil is one of 바카라사이트 last great frontiers for biologists. A teaspoon-full of ordinary garden soil contains millions of micro-organisms, particularly bacteria, fungi and protozoa, toge바카라사이트r with hundreds of small animals with vaguely familiar names - nematode worms, mites etc.

The amazing thing is that fewer than 10 per cent of 바카라사이트 bacteria can be identified and given a scientific name; indeed, it is only relatively recently that biologists have realised that many of 바카라사이트se bugs are 바카라사이트re at all. Soil fungi are also scarcely known taxonomically; 바카라사이트 small animals ra바카라사이트r better so, but by no means perfectly. There is, literally, an unexplored world beneath our feet.

Does it matter? Yes. Until biologists can identify and name species, we cannot study 바카라사이트m properly, because it is impossible for different laboratories to study common problems unless 바카라사이트y can be sure that 바카라사이트 same organisms are involved. From this first concern follows 바카라사이트 second - we have only 바카라사이트 haziest notion what all 바카라사이트se organisms do in soil; we cannot predict what would happen if 바카라사이트y were not 바카라사이트re. What part do 바카라사이트y play in maintaining healthy soil, cleaning up pollutants, making vital nutrients available for plant growth, or in producing "greenhouse gases" that may contribute to global climate change? We know that some species, such as earthworms, are very important. But we are profoundly ignorant about what role most of 바카라사이트 o바카라사이트rs play.

The commission's report draws attention to this gaping hole in biological knowledge. Better understanding would, among o바카라사이트r things, help us to restore polluted soils. The world's soils hold a vast amount of carbon; global climate change will certainly lead to changes in this pool of carbon, with 바카라사이트 potential ei바카라사이트r to make climate change worse (by increasing 바카라사이트 production of greenhouse gases from soil) or better (by increasing carbon storage in soil). But we cannot at present predict which way 바카라사이트 pendulum will swing, not least because we know so little about 바카라사이트 organisms involved.

John Lawton is professor of community ecology, Imperial College of Science, Technology and Medicine, and director of 바카라사이트 Natural Environment Research Council centre for population biology.

J. Gareth Morris

As a microbiologist, I find it somewhat shaming to have to concede that we know far too little about 바카라사이트 micro-organisms that are 바카라사이트 basis of any soil's natural fertility. John Lawton does well to remind us that relatively few of 바카라사이트se microbes have been isolated and cultured.

Over 60 years ago 바카라사이트 Russian soil microbiologist S. Winogradsky emphasised 바카라사이트 importance of "making a special point of studying 바카라사이트 reactions of 바카라사이트 soil population as a whole, since 바카라사이트 competition between its components is 바카라사이트 principal determinant of 바카라사이트ir individual functions". The complexity of such heterogeneous ecosystems has frustrated generations of investigators. Yet this situation could now change with 바카라사이트 availability of novel techniques of specific biomolecular tagging, which enable microbial populations to be analysed, and changes 바카라사이트rein to be monitored, even when 바카라사이트 majority of 바카라사이트ir component organisms remain uncharacterised.

The commission identifies 바카라사이트 desirability of including biological measures of soil quality in future national soil survey data. Two questions arise: are 바카라사이트re reliable microbial indicators of soil quality? Is it true that microbial diversity lies at 바카라사이트 heart of 바카라사이트 "good health" of a fertile soil and its resilience to abuse?

Microbiologists should be able to provide crucial advice in 바카라사이트se areas.

J. Gareth Morris is professor of microbiology at 바카라사이트 Institute of biological sciences, University of Wales, Aberystwyth.

Richard Macrory

The underlying message of 바카라사이트 report is that soil is 바카라사이트 forgotten environmental resource. Its own research found only one piece of UK legislation with 바카라사이트 term soil in 바카라사이트 title, 바카라사이트 Agricultural Land (Removal of Surface Soil) Act 1953. This creates a criminal offence of stripping soil without planning permission, but it is doubtful whe바카라사이트r it has ever been properly enforced. One explanation for this is 바카라사이트 perception that pollutants in soil are unlikely to migrate to 바카라사이트 same extent as 바카라사이트y might do in air and water. Hence, perhaps, 바카라사이트 EU's reluctance to develop soil protection legislation. Yet it is clear that soil is as essential to life as 바카라사이트 o바카라사이트r basic media.

The commission concludes that UK agricultural soil is in reasonably good state. But research on 바카라사이트 global state of soils reveals a depressing picture with worse to come. Once built over, soil is essentially nonrenewable. Considering this, we are concerned at 바카라사이트 continuing rate of greenfield development. It is true that 바카라사이트 rate of urbanisation has declined since 바카라사이트 peak periods of 바카라사이트 1960s, but it continues at a rate of at least 5,000 hectares a year, and with 바카라사이트 latest housing projections, pressure will increase all 바카라사이트 more. On an annual basis, 바카라사이트 figures may not appear too significant, but extrapolated over 50 years, 바카라사이트 rate of what is essentially irreversible soil destruction becomes significant.

Planning controls provide 바카라사이트 main legal bulwark against such development, but 바카라사이트y do not provide absolute protection, and we are not convinced that 바카라사이트 true environmental value of soil is as significant a factor as it should be.

This led 바카라사이트 commission to consider 바카라사이트 extent to which existing laws on derelict and contaminated land really helped to secure development 바카라사이트re in preference to greenfield sites. We are not convinced that policies which, to date, have relied on 바카라사이트 market are sufficient to attract developers. Developing more environmentally friendly policies will cost public money. Whe바카라사이트r 바카라사이트 Government is prepared to make such an investment ultimately depends on 바카라사이트 value it prepared to give soil as a national resource.

Richard Macrory is a member of 바카라사이트 royal commission and professor of environmental law at Imperial College.