Reforestation

Forests in Appalachia provide valuable ecosystem services, including maintaining freshwater resources [1,2]. Unfortunately, Appalachian forests are threatened by a several short- and long-term pressures including climate change, species invasions, resource extraction (coal, timber, gas), and straight piping of sewage. Resource extraction in the form of surface coal mining has resulted in significant land use change in Appalachia, reducing native forest cover, causing forest fragmentation, and eliminating native soil [3,4]. Surface mining has also impaired the region’s water resources through alterations in hydrology and degraded water quality both during extraction and reclamation. In a traditionally reclaimed site (grassland), many components of the natural forest’s hydrologic cycle are altered due to lack of canopy cover and changes to physical properties of the soil [5,6]. Canopy interception (and interception loss) are expected to be lower in conventionally reclaimed sites due to the lower structural complexity of the canopy (fewer layers of vegetation and less surface area). Soils at conventionally reclaimed sites tend to be compacted, which limits infiltration and rooting volumes. These combined influences result in reduced evapo-transpiration (ET), increased overland flow, erosion and sedimentation. Reclamation using the Forestry Reclamation Approach (FRA) – a technique found to restore hardwood forests on surface-mined lands successfully – could lead to the production of a canopy that functions similar to a natural forest, providing soil that promotes infiltration and water storage, and enhancing water quality [3,7-9]. Unfortunately, little information exists to test these hypotheses. As the FRA is a relatively new concept, sites old enough in terms of forest growth to conduct the necessary experiments have only recently become available.

Given all these issues, management solutions to protect water resources in Appalachia must be developed, UK’s Robinson Forest providing an ideal setting to examine the impact of land use on water resources. Indeed, the forest contains a hydrologic network that has been continuously monitored since the early 1970s. Additionally, resource extraction in the form of timber harvesting and surface coal mining has occurred on the site, resulting in a myriad types-of-land-disturbance and times-from-impact. Thus, the opportunity exists to examine how mining and reclamation affect forest regeneration and its influence on watershed function (annual streamflow, storm flow response, evapotranspiration, water chemistry, and erosion), within sites ranging from 1 to 20 years since being planted. Moreover, the capability to examine how resource extraction affects watershed functions – and to determine what measures could be employed to minimize these impacts (such as the FRA) – is also in place. Lastly, climate and forest range modeling techniques are available to examine the recovery (restoration or natural regeneration) of forest stands and watershed function at the watershed scale. A better understanding of how land use and restoration influence water resources will enable not only forecasting of future problems, but also assessment of the economic, environmental, social, and/or infrastructure costs associated with proposed solutions.

Proper management of water resources is critical to the development of sustainable energy and food production systems, as areas impacted by resource extraction face numerous challenges related to altered water quantity and quality. An LCA will be developed to further inform how these management solutions impact the long-term sustainability. Utilizing a cradle to grave approach to evaluate this model will rely heavily on the data that has been collected over time for these different management strategies and the expertise of the NRT participants. The results from this study are applicable to other regions as land use impacts present in Appalachia are not unique to the region but extend throughout the U.S. and even worldwide. Moreover, understanding how to restore hydrologic and water quality functions to impacted lands is a critical need not only environmentally, but also economically and socially.

Specific objectives of this research are: 1) to compare water quality attributes resulting from various surface mine reclamation strategies (including conventional grassland reclamation and FRA using unmined forests as benchmark) to assess reforestation effectiveness for water pollution control; 2) to compare hydrologic functions (including streamflow, canopy interception, stemflow, and soil saturated hydraulic conductivity) across these surface mine reclamation strategies to evaluate the influence of mine reforestation on the water cycle; and 3) to develop an LCA to evaluate forestry reclamation strategies in the region.

This NRT builds upon decades-long research at UK and provides both a unique research setting for evaluating the effectiveness of the FRA and interdisciplinary research opportunities in the field of forest hydrology, mine reforestation and economics.

References

1. Gomi, T.; Sidle, R. C.; Richardson, J. S., Understanding processes and downstream linkages of headwater systems: headwaters differ from downstream reaches by their close coupling to hillslope processes, more temporal and spatial variation, and their need for different means of protection from land use. BioScience Vol. 52 (10), pp. 905-916, 2002.
2. May, C. L.; Gresswell, R. E., Large wood recruitment and redistribution in headwater streams in the southern Oregon Coast Range, USA. Canadian Journal of Forest Research Vol. 33 (8), pp. 1352-1362, 2003.
3. Zipper, C. E.; Burger, J. A.; Skousen, J. G.; Angel, P. N.; Barton, C. D.; Davis, V.; Franklin, J. A., Restoring forests and associated ecosystem services on Appalachian coal surface mines. Environmental Management Vol. 47 (5), pp. 751-765, 2011.
4. Sayler, K. L. Central Appalachia, USGS land cover trends project. 2012. http://landcovertrends.usgs.gov/east/eco69Report.html.
5. Guebert, M. D.; Gardner, T. W., Macropore flow on a reclaimed surface mine: infiltration and hillslope hydrology. Geomorphology Vol. 39 (3), pp. 151-169, 2001.
6. Shukla, M.; Lal, R.; Underwood, J.; Ebinger, M., Physical and hydrological characteristics of reclaimed minesoils in southeastern Ohio. Soil Science Society of America Journal Vol. 68 (4), pp. 1352-1359, 2004.
7. Agouridis, C. T.; Angel, P. N.; Taylor, T. J.; Barton, C. D.; Warner, R. C.; Yu, X.; Wood, C., Water quality characteristics of discharge from reforested loose-dumped mine spoil in eastern Kentucky. Journal of environmental quality Vol. 41 (2), pp. 454-468, 2012.
8. Miller, J.; Barton, C.; Agouridis, C.; Fogel, A.; Dowdy, T.; Angel, P., Evaluating soil genesis and reforestation success on a surface coal mine in Appalachia. Soil Science Society of America Journal Vol. 76 (3), pp. 950-960, 2012.
9. Sena, K.; Barton, C.; Angel, P.; Agouridis, C.; Warner, R., Influence of spoil type on chemistry and hydrology of interflow on a surface coal mine in the eastern US coalfield. Water, Air, & Soil Pollution Vol. 225 (11), pp. 2171, 2014.