What of the Future? - Climate Change Impacts on Freshwater Ecosystems - page 295

dilute solution of sea water. In turn, the slightly salty water had provided sulphates
and chlorides that acidified the soil when the bases in the water were taken up by
plants. Other forms of acidification had been a problem in the late 20th century
as a result of coal burning in power stations (producing sulphur oxides) and from
vehicle engines (producing nitrogen oxides and eventually nitric acid in the
atmosphere) and through release of ammonia from the decomposing excreta of
intensive stock keeping. Scrubbing the sulphur oxides from the chimney gases
had solved the first, and the second was helped by the high cost of fuel in the 21st
century, leading to many cars resting idle on driveways.
The third problem was still extant, and the increased rainfall and the sea spray
it brought were amplifying the acidification in the uplands. It led to losses of fish and
invertebrates, even of some stream birds like dippers, and expectations a few
decades earlier of its complete solution now seemed over-optimistic. Eutrophication
symptoms had increased everywhere with warming, and acidification was not
solved; river engineering continued apace to try to avoid flooding; and traces of
agricultural and industrial chemicals still contaminated the waters, though the
line of discharge of gross pollutants had been held. There were subtle changes in
fisheries as conditions in the south became too hot for some species and, with no
possibilities for invasion of warm-adapted species from the mainland, communities
became impoverished. There were more accidentally or deliberately introduced
exotic species and since most came from warmer regions, many were growing
well.
Sometimes only professional ecologists noticed such species, if they were
small, but the damage wrought by carp, as it converted clear plant-dominated
lakes to turbid ones, and the overweening growth of some floating plants were
very obvious. In terms of problems in freshwaters, it was as if no real progress
had been made in 50 years, despite much legislation. Only at the coast, where the
innocently rising sea level masked the exertion of huge forces, was there much
reinstatement of more natural conditions. The residents of coastal villages were
very concerned.
That concern was universally shared as temperatures rose by 4 °C over those in
the 20th century by the late 21st century. It was not as if life was impossible, but
it was very difficult. There was immense pressure on water supplies, for millions
of refugees from the now intensely dry and hot southern parts of Europe had
poured in to take advantage of the cooler offshore climate. Their entry was legal
until eventually the Government withdrew from the European Union so as to
stem the flow. Indeed the Union was in great danger of breaking up entirely as
northern states looked to their borders and southern states fell into chaos. Travel
had become very expensive, so the mutual understanding brought about by
frequent visits and meetings among people of different countries had been denied
to the new generations, which were lapsing into a historically precedented
isolationism. The land was much more built over, food was rationed; the patchwork
of small fields in the landscape had entirely gone, except in the hills, where every
piece of land had some chickens and sheep. Maize was grown on an industrial
scale in huge fields and people's diets were much less varied than they had
previously been. Most ponds had been filled in; amphibia had virtually disappeared.
The common toad was now a very rare toad. In the warmer parts, every lake and