Two field trials were established in1991to determine the effects on crop yield, N uptake, soil moisture content and heavy metal concentration of applying de-inked paper mill sludge (DPMS) over the period 1991 to 1993. In the first year, during decomposition of the DPMS, N immobilization occurred resulting in loss of cereal yield (P`0.05) at low rates of N fertilizer. Approximately 40 kg extra N fertilizeraha was required per 100 t DPMSaha to compensate for this N immobilization. Soil volumetric moisture content was increased (P`0.001) by c. 20% at both sites by 200 and 300 t DPMSaha. DPMS did not significantly increase (P b 0.05) soil concentrations of total Zn, Cu and Pb. Soil nitrate concentrations after harvest were reduced (P`0.01) by c. 17 mg Nakg per 100 t DPMSaha with increasing rates of DPMS up to 200 taha. In the second year following the DPMS application, there were no significant effects on grain yield indicating that very little or no N was immobilized. By the third year, the soil N supply was 7 kg Naha higher where a single dressing of 100 t DPMSaha had been applied compared to the control. This resulted in an overall yield increase of 7% (P`0.10). Soil N supply was lower (N.S.) but crop yields were similar (P b 0.05) to the control where single dressings of 200 and 300 t DPMSaha had been applied.

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Soil fungal communities vary spatially due to factors including variations in plant diversity and soil characteristics; however, the relative influences of these factors on composition and therefore function remain unclear. Small-scale variation in fungal communities may drive local variation in nutrient cycling and decomposition and may respond more to local factors compared with large climatic variations. Clarifying the roles of these factors can improve our predictions of soil fungal community and biogeochemical cycling responses to anthropogenic changes. Therefore, we examined relationships among abiotic and biotic factors and soil fungal communities associated with Quercus rubra and Pinus resinosa saplings and mature trees in a mixed-hardwood woodland. We also compared community composition and fungal enzymatic activity. Fungal community composition was associated with spatial heterogeneity of soil characteristics, while host sapling and tree species identity were poor predictors of community composition. Further, most of the compositional variation was unexplained by measured variables, suggesting stochasticity and other environmental characteristics may drive spatial variation in these communities. Additionally, enzymatic activity did not clearly correlate with fungal community composition. Overall, soil fungal communities and enzymatic activity adjacent to saplings in this woodland are influenced primarily by soil characteristics and stochasticity and not plant identity.