Title Authors Year
Physiological effects of long term exposure to low concentrations of SO2 and NH3 on poplar leaves.

Hove, L.W.A…

1991
Increases in soil acidity in north west Wales between 1957 and 1990

…

1991
Mechansims of adaptions of plants to acid soils

Marschner,…

1991
The Distribution and Breeding Site Characteristics of Newts in Cumbria, England.

Denton, J.S…

1991
Changes in species composition of semi-natural vegetation associated with the increase in atmospheric inputs of nitrogen

Pitcairn, C…

1991
Critical Load Maps for the United Kingdom I: Soil

UKCLAG,

 		1991
A Field-Study of Fertilization and Embryonic Development in the Common Frog (Rana-Temporaria) with Particular Reference to Acidity and Temperature

Beattie, R.…

1991
Acid rain since 1985 - times are changing

Brydges, T.…

1991
Effects of nitrogen loading on wetland ecosystems, with particular reference to atmospheric deposition

Morris, J.T…

1991
Zeigerwerte von Pflanzen in Mitteleuropa

Ellenberg,…

1991