Читать книгу Green and Prosperous Land - Dieter Helm, Dieter Helm - Страница 16

The easy bit is the non-renewables which, as the name implies, can be used once.⁶ Nature has endowed us with them – they are natural – but they do not renew themselves except over geological time. They include the coal, iron ore, tin, oil and gas upon which our economy has been built and remains utterly dependent. Unsurprisingly, we know a lot about them. There are detailed measurements of the volumes mined and extracted, and there is also price data. This least interesting dimension of natural capital is the easiest to measure. It is also the dimension of which, by 2050, much will have been exhausted or, in the case of coal, oil and gas, hopefully left in the ground. In chapter 10, we will see that we should compensate future generations for what we have consumed, and for the legacy of carbon and other mineral pollution we have left behind from our largely selfish use of these non-renewables.

When it comes to the really important stuff, the renewables – the natural capital that nature can keep on giving us for ever – there are two obvious starting points. The first is the bits we are familiar with: the birds, plants, mammals, fish and invertebrates. The second, the one we concentrate on throughout, is the habitats and ecosystems, including the river catchments, the farmed lands, the uplands, the coasts and the urban areas.

How bad could the river catchments get in a business-as-usual scenario? Think of the stresses they already face. If you drink tap water in London it is often said that it may have already been through up to seven people.⁷ That water will have been abstracted from rivers and cleaned of all the chemicals that have leached into it, and will be again after your sewage has been collected, processed and discharged back into the river. It might also include raw sewage from storm overflows. The sewage, before it is treated, will be contaminated with pharmaceutical products. Take a look in the cupboard under your sink. See the cleaning fluids you put down the sink and the toilet. Take a look in your bathroom at all the products you use. Many of these end up down the plughole, and we all just expect the environment – in this case the rivers – to absorb them. You turn on the tap and you expect clean water to flow. You water your garden and wash the car with this costly, treated water, and you don’t want to pay much for it.

Yet that is just the beginning. We go on tipping more and more fertilisers, pesticides and herbicides into our watercourses, and allow the silt to run off the land from intensive farming practices. Industry adds its pollution too. Add all the plastic and other rubbish that gets thrown in and you can see the results alongside any major river.

Now add another quarter-century of all this. Add more and more chemicals, and more demand for more water for everything from land irrigation to servicing the expanding population. The National Infrastructure Commission⁸ recommends a new water grid to connect major rivers just to meet demand (and without much regard for the environmental consequences of the mixing of waters).⁹

Now add climate change on top. You may be confused by the various claims about the impacts of climate change. Droughts, floods and plagues make the headlines, and dire warnings may induce scepticism or, worse, fatalism, but behind the hysteria lie some very inconvenient predictions. Heat in summer means more demand for water.¹⁰ Floods in winter mean more silt and more pollution. The river life is adapted to what we have, not the climate we might get. For the river catchments, business-as-usual for another quarter of a century looks bad.

Agriculture plays a big part in both water demand and pollution and much else. A common theme in all these sad tales of decline is the impacts of modern farming not just on specific species, but on farmland birds generally and on the state of our rivers and on inshore marine environments and on the emissions and air-quality consequences and on the loss of invertebrates and mammals and the serious decline in the soils. It is beyond doubt that it is the intensification of farming, and in particular the application of chemicals, that is a primary driver of this major environmental damage.

By 2050, targeted chemicals should be able to get rid of almost anything that competes with or damages crops. Indeed, many can now. Almost all arable weeds (and in some robotic applications every individual weed) can be killed off with the non-selective herbicide glyphosate. That is why one well-known brand is called ‘Roundup’. As glyphosate comes under increasing regulatory scrutiny, replacements are on their way. Without a change of direction in agriculture, by 2050 herbicides will be completely and selectively engineered for specific crops, and pesticides will finish off specific insects. Ultimately nothing will be left for wildlife to eat. By 2050 it will largely be over.

The uplands will not escape these pressures in the business-as-usual scenario. Being home to a lot of biodiversity now does not mean they will continue to be so. The economics of marginal upland farming is already precarious. If and when the main elements of the CAP wither away, and in the absence of proactive efforts to protect and enhance the uplands, things could go downhill very quickly. This farmed landscape could revert to ranch-style extensive farming, to intensive game-shooting and to development. Worse still, it might simply be abandoned. The rewilders might like this idea. Let the scrub grow back and then the woodlands re-clothe the hills. Except it will not be like this. The uplands are farmed landscapes. It is farmers who have shaped the landscapes that so many people, and so much of nature, enjoy. Farmers created the hedgerows, and the ditches and the lanes and the meadows. Grazing stock is the essence of the uplands. Woodland birds and woodland mammals might benefit, but this will not conserve the nature and landscapes we so admire today. By 2050 the uplands may be playgrounds still, but not the playgrounds we know now. Few think that zero subsidies will produce a helpful answer, except those who simply want us humans to abandon the land.

The impacts of farm pollution are exacerbated by other developments. Fish farms bring direct pollution to our coasts, and perhaps even more pernicious is the harvesting of sand eels and other small marine life to feed the farmed salmon. Direct pollution from shipping, from oil slicks and the washing of tanks at sea (including now palm oil), to the illegal dumping of waste and chemicals, all contribute to the declines. Plastics have become ubiquitous in our seas and along our coasts. Their sources are all largely out of sight, diffuse, and able to escape the law.¹¹ These are largely out of control. By 2050, with lots more trade and shipping, with lots more fish farms, and with global warming impacting on already stressed ecosystems, there may be no puffins, few gulls, and below the surface a more lifeless habitat. By 2050, eels and wild salmon might be an occasional rarity, as their populations decline below the thresholds for renewing themselves naturally.

The threats to our urban environment out to 2050 are about both its size and its content. There can be little doubt there is going to be a lot more ‘urban’ in 25 years’ time. More greenfield and brownfield sites¹² will be built on, new villages and towns will be built, and the built land area will absorb more and more of the Green Belt. There will be quite a lot of semi-urban sprawl for the ‘executive homes’ so beloved and profitable to the building companies. It is not inevitable that all of these developments will have less biodiversity than the land they concrete over. But concrete they will, and without strong net environmental gain compensations, the aggregate impacts are probably going to be worse. For every showcase green development project, there are many that are anything but.

In terms of the content of urban areas, the temptation to concrete over the green spaces in our towns and cities will become increasingly intense. The parks and gardens are going backwards for a variety of reasons, and over the next quarter of a century, if we carry on as we are, these will gradually disappear. What remain may be turned into amusement parks, and nature will get squeezed out. Brownfield sites, even where they have surprisingly high levels of biodiversity, will go under concrete.