No abstract

Since its establishment around 1990, the Ecological Conditions Database (EC; GIVD ID EU-00-006) has been accumulating vegetation relevés from the Netherlands, each accompanied by at least one abiotic soil measurement (e.g. pH or nutrient availability). On 1-1-2010, the database contained 8,229 relevés, covering the period from 1936 to 2009, and representing contributions from 110 authors. The most frequently measured soil parameter is pH, with well over 5,000 entries. All the data in the database are subjected to ISO 9001 quality control. The database can be used as the starting point for estimating plant species responses to a range of abiotic variables, such as pH, groundwater table, or nitrate concentration, and for vegetation modelling (model parameterisation and validation).

No abstract

The forest communities of northeastern Pennsylvania are diverse due to variation in climate, geologic history, soil types, and topography. This research specifically surveyed the forest communities of the Bear Creek region of southeastern Luzerne County, Pennsylvania. The purpose of this study was twofold: (a) to document the current forest community composition and to compare the forests of today to the last known forest survey in this area completed by Donahue in the early 1950s; and (b) to propose explanations for the differences observed between the two survey periods. The upland forest community surveyed by Donahue was dominated by red maple (Acer rubrum ) and oaks (Quercus alba and Quercus rubra), with these three species accounting for 78.4% of all stems recorded. In contrast, the contemporary upland forest is now dominated by oaks (Q. alba and Q. rubra), with a subdominant layer composed of Acer saccharum, A. rubrum, and Sassafras albidum.

No abstract