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

Beattie, R.…

1991
Critical Load Maps for the United Kingdom I: Soil

UKCLAG,

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

Pitcairn, C…

1991
Zeigerwerte von Pflanzen in Mitteleuropa

Ellenberg,…

1991
Influence of HN3 and (HN4)2 SO4 on heathland vegetation

Van der…

1991
Physiological-effects of long-term exposure to low concentrations of SO2 and NH3 on poplar leaves

Hove, L.W.A…

1991
Nitrogen Uptake and Allocation by Calluna-Vulgaris (L) Hull and Deschampsia-Flexuosa (L) Trin Exposed to 15NH3

Dueck, T.A…

1991
Forestry and soil protection in the UK

Moffatt, A.…

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

Denton, J.S…

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

…

1991