| Title | Authors | Year |
|---|---|---|
| Increases in soil acidity in north west Wales between 1957 and 1990 |
… |
1991 |
| Changes in species composition of semi-natural vegetation associated with the increase in atmospheric inputs of nitrogen |
Pitcairn, C… |
1991 |
| Decline of ectomycorrhizal fungi in Europe. |
Arnolds, E… |
1991 |
| Zeigerwerte von Pflanzen in Mitteleuropa |
Ellenberg,… |
1991 |
| Air pollution and agriculture |
Ashmore, M.… |
1991 |
| The yield of winter cereals exposed to sulphur dioxide under field conditions. |
McLeod, A.R… |
1991 |
| The Distribution and Breeding Site Characteristics of Newts in Cumbria, England. |
Denton, J.S… |
1991 |
| Conservation of freshwater fish in the British Isles: the current status and biology of threatened species. Aquatic Conservation |
Maitland, P… |
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 |