| Title | Authors | Year |
|---|---|---|
| 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 |
| 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 |
| Nitrate in soil water |
Westling, O… |
1991 |
| Decline of ectomycorrhizal fungi in Europe. |
Arnolds, E… |
1991 |
| Air pollution and agriculture |
Ashmore, M.… |
1991 |
| Nitrogen Uptake and Allocation by Calluna-Vulgaris (L) Hull and Deschampsia-Flexuosa (L) Trin Exposed to 15NH3 |
Dueck, T.A… |
1991 |