SOIL NUTRIENT INPUT EFFECTS ON SEED LONGEVITY - A BURIAL EXPERIMENT WITH FEN-MEADOW SPECIES

1. Effects of high nutrient input on the longevity and viability of bu ried seed are examined. Seeds of 17 fen-meadow species were buried in nylon mesh bags at four sites in the Netherlands and one site in Great Britain in plots to which N, P, K fertilizers are applied. Prior to b urial germination tests were conducted on the seeds of each species. T his paper describes the results of the viability tests on the seeds th at were exhumed after one and 2 years of burial.2. The percentage of s eeds that germinated after 1 year of burial was significantly lower th an the pre-burial percentage for the majority of the species. After 2 years of burial the germination percentage further decreased. A few sp ecies, such as the Carex species, did, however, show an increase in ge rmination percentage indicating that the burial conditions allowed dor mancy controls to be broken. 3. Differences in the edaphic conditions between the sites appeared to affect germination percentages after 1 y ear of burial. A difference in germination response between sites was observed for Carex acutiformis, Filipendula ulmaria and Lychnis flos-c uculi. 4, A significantly higher germination percentage was found at t he Great Britain site for F: ulmaria in the phosphate treatment compar ed with the potassium treatment and the control after 1 year of burial . In contrast to many literature assessments no significant effects of fertilizer application was found after 2 years. 5. For all sites, exc ept one in the Netherlands, the total number of seeds that germinated was lower in 1996 than in 1995.