| Title | Authors | Year | 
|---|---|---|
| Acid deposition: its nature and impacts | 
                               Last, F.T…  | 
                                                                                        1991 | 
| Concurrent exposure to SO2 and/or NO2 alters groweth and Yield responses of wheat and barley to low concentrations of O3. | 
                               Adaros, G…  | 
                                                                                        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 | 
| Acidic deposition: its nature and impacts | 
                               Last, F.T…  | 
                                                                                        1991 | 
| Increases in soil acidity in north west Wales between 1957 and 1990 | 
                               …  | 
                                                                                        1991 | 
| Mechansims of adaptions of plants to acid soils | 
                               Marschner,…  | 
                                                                                        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 | 
| Acid Rain - Critical and Target Load Maps for the United Kingdom | 
                               Environment…  | 
                                                                                        1991 |