Development of Ecosystem Structure and Function On Reforested Mined Lands.

Coal mining has drastically disturbed 600,000 ha of land in the Appalachian region since the 1800’s. Prior to mining, this land was primarily vegetated by mixed hardwood forest. Only in the last few decades has research emphasized the reestablishment of the forest ecosystem. Great strides have been made in tree establishment and survival, yet questions remain as to whether the replanted trees are able to provide the same ecological functions as the native forests. The objectives of this study were to quantify ecosystem processes occurring on the reforested mine land and to relate ecosystem structural development to these processes. A chronosequence of five sites, 5, 10, 20 and 30 years post-reclamation and an unmined site, were analyzed. Total and plant-available soil nutrient pools (carbon (C), nitrogen (N), phosphorous (P), and other macro- and micro-nutrients) were quantified at depths 0-5 cm, 5-10 cm and 10-25 cm. C and N were quantified by dry combustion on an elemental analyzer and the other nutrients by the EPA 3050b acid digest. Key C and N transformations were measured monthly throughout the growing season by static chamber gas flux measurements of carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄). Ion exchange membranes were used to capture plant-available nutrients. Active microbial biomass was quantified using substrate-induced respiration and total microbial biomass by chloroform fumigation. These methods elucidate some of the soil processes occurring at each age cohort, allowing comparisons of development.