Importance of calcium-rich substrates for supporting refugia of biodiversity and productivity in an increasingly acidified landscape THEME FOUR PI: Colin Beier ([email protected]) CoPI: Myron Mitchell, James Gibbs, Don Leopold, Martin Dovciak SUNY College of Environmental Science and Forestry SUNY ESF Adirondack Ecological Center 6312 State Route 28N, Newcomb, NY 12852 Gregory Lawrence, US Geological Survey, Troy, NY Blair Page, Onondaga Community College, Syracuse, NY Project completion date: August 31, 2010

• GASTROPOD AND SALAMANDER COMMUNITIES WERE STRONGLY SHAPED BY SOIL CALCIUM AVAILABILITY IN HARDWOOD FORESTS ACROSS THE ADIRONDACK PARK, NY

• PATCHES OF CALCIUM-RICH FORESTS SUPPORT HIGHER BIODIVERSITY

Funding support for this project was provided by the Northeastern States Research Cooperative (NSRC), a partnership of Northern Forest states (New Hampshire, Vermont, Maine, and New York), in coordination with the USDA Forest Service. http://www.nsrcforest.org Project Summary

Acid rain has been a chronic and pervasive problem across much of the Northern Forest for decades. Acid rain causes the leaching and loss of calcium (Ca), a critical nutrient for all organisms, from forest soils. However, the impact of Ca depletion on forest organisms and ecological communities is not well understood in the Northern Forest region. In some forests, the presence of Ca-rich bedrock provides a buffering capacity that resists acidification and helps to maintain the availability of Ca in the food web.

We studied the potential importance of these Ca-rich forest patches by sampling snail, salamander, arthropod and plant communities in the Adirondack Mountains of northern New York. We selected twelve sites representing the full range of soil Ca in the Adirondacks to determine whether differences in biodiversity and productivity were related to the availability of Ca. We also sampled the diets of woodland salamanders to understand how Ca influences the forest floor food web.

We found that snail and salamander communities were strongly influenced by soil Ca, while the effect of Ca on plant and insect communities was less clear. Snail abundance and diversity was positively related to soil Ca. Red-back salamanders – a keystone species in northern hardwood forests – increased in abundance with increasing soil Ca. Several snail and plant species were found only at the 2-3 highest Ca sites, indicating that these forests may act as refuges for highly Ca-dependent organisms.

Overall, this study provided evidence of the importance of Ca for many different forest species and communities, which will support future research, conservation and regulatory efforts to mitigate acid rain impacts in the Northern Forest region. Background and Justification

• Effective conservation of biodiversity in an era of rapid environmental change requires attention to how protected ecosystems may respond to larger-scale human impacts.

• In the Northern Forest, key drivers of change during the 20th century have included land use change, acid rain, climate change, and forest diseases/pests.

• Although climate change and forest diseases/pests are currently the major concerns for land managers, decades of acid rain have influenced how the Northern Forest ecosystems will function and respond to these future changes.

• Acid rain causes the leaching and loss of calcium (Ca) from forest soils

• Calcium is an essential nutrient for all organisms and is critical for songbirds and snails

• Evidence suggests negative impacts on species and ecological communities exposed to acid rain, due the reduction of calcium (Ca) available to these organisms.

• Relatively little is known about the impacts of acid rain and Ca depletion on forest communities in the Northern Forest region

• Patches of Ca-rich bedrock may support greater capacity for the ecosystem to maintain enough Ca, which may allow a larger diversity of species to survive Methods

• We selected twelve (12) sites in upland northern hardwood forests in the Adirondack Mountains, NY where prior studies had recently measured soil chemistry, including Ca.

• We established a group of sample plots at each site, in very close proximity to where soils data were collected by our cooperators (G. Lawrence and B. Page).

60

Oa Ca B Ca SO4 deposition NO3 deposition

50 (kg/ha/yr) 40

Deposition 30

/kg) or /kg) 20 cmol

10 Soil Ca ( Ca Soil 0 Plot and sampling design Methods

• Snails: We used both litter sieving and timed search methods. Within the center plot, we collected a total of 1m2 of leaf litter in four equal amounts. Litter was air-dried, sieved into four fractions and searched for shells and shell fragments. We also searched for snails for a total of 240 minutes at each site. All snails were tallied and nearly all individuals collected were identified to species.

• Soil arthropods: Within the center plot, we collected a total of 1m2 of leaf litter in four equal amounts and placed the litter into a Berlese funnel apparatus. All organisms were collected in glass sample jars with 15% ethanol and identified.

• Salamanders: We used timed search and gastric lavage methods to collect woodland salamanders and assay their diet. All collected salamanders were identified to species, measured, weighed and released. Using a syringe and distilled water, we conducted gastric lavage on all salamanders collected during a separate (and second) pre- dawn round of sampling of our sites. Stomach contents were collected in glass vials and analyzed using a dissecting microscope.

• Plants: We measured diameter of overstory and understory trees, presence/absence of herbaceous plants, and percent forest floor cover (12 cover classes) in a group of vegetation plots at each site (Fig. 2). Analysis

• We used correlation analysis and linear regression models to determine influence of soil Ca on forest communities:

• Predictor variables: soil Ca, acidic (NO3,SO4) deposition estimates, site elevation • Response variables: abundance (snails, salamanders, arthropods), total basal area (trees), species basal area (trees), species richness (snails, salamanders, arthropods, plants), community diversity (snails, salamanders, arthropods), percent cover (forest floor)

• Used analysis of variance and rank correlations to compare the composition of diets between the two primary salamander species (redback and northern dusky)

• Non-metric multidimensional scaling (NMS) used to understand the relationships among species, sample sites and environmental gradients

Results

Relationships between snail species richness and soil Ca (left) and SO4 deposition (right).

Our results indicate that species richness of forest snails increases with increasing soil Ca, and decreases with increasing amounts of acidic (SO4) deposition, or acid rain.

Several families of snails were only found at the two highest-Ca sites Results

We found a strong positive effect of Ca on the abundance of red- back salamanders

As Ca increased, the abundance of dusky salamanders decreased, and the abundance of red-back salamanders increased

Red-back salamanders are very territorial and may be driving off other salamander species at the Ca-rich sites

We are studying the diets of salamanders to see if diet explains these relationships Results

Ordination plot shows that most species are organized around the interactions between soil Ca and acidic (SO4) deposition Implications and Applications

• First study in Northern Forest to show importance of Ca and potential impacts of acid rain for multiple forest communities and their relationships (such as food webs)

• Learned that our region’s most abundant vertebrate – the red-back salamander – has a strong relationship with the availability of Ca in forest soils

• Verified that the region’s land snail fauna are excellent bio-indicators of soil chemistry

• Identified several species that are highly Ca-dependent that only live at Ca-rich sites

• Identified several patches of Ca-rich soils that may serve as refuges from acid rain

• Provided an easily repeatable basis for evaluating and comparing other forest sites

• Can support the prioritization of conservation actions, such as protecting areas with Ca- rich soils that support greater biodiversity and productivity

• Contributes to ongoing experimental restoration efforts, such as the use of limestone and/or other Ca additions to watersheds affected by decades of acid rain

Future Work

• In process of completing revisions to provisionally accepted manuscript (CJFR) • Currently completing the analysis and write-up of arthropod and salamander diet data from the Adirondack sites (by Caitlin Snyder, MS student at ESF)

• New NSRC Theme Two project to expand the geographic scope of the study to include sites in Vermont, New Hampshire and Maine • Collaboration with Scott Bailey (US Forest Service) and colleagues • 20-25 additional sites including several with higher soil Ca than current sites • Coordinate sampling with Ruth Yanai’s ‘shoestring’ project in VT and NH

• New Audubon NY funding to study songbird communities at existing Adirondack sites (by Jennifer Yantachka, MS student at ESF, advised by C. Beier)

• NSF Postdoctoral Fellowship proposal by Sarah Pabian, in collaboration with Charles Driscoll, to use snails and songbirds to study the relationships between Ca and mercury flows in terrestrial food webs in the Adirondacks

• As we complete the new study in VT, NH and ME, we plan to work with local and regional scientists and conservation organizations to implement our findings • Map conservation priorities using existing data and our research findings • Share field protocols to encourage forest ‘bio-blitzes’ to gather extensive data that supports research and education of acid rain impacts across Northern Forest List of Products

• Paper in Canadian Journal of Forest Research provisionally accepted with revisions • Beier CM, Woods AM, Hotopp K, Mitchell MJ, Leopold DJ, Gibbs JP and Dovciak M. In revision. Soil calcium influences forest communities at multiple trophic levels in northern hardwood forests of the Adirondack Mountains, NY. Canadian Journal of Forest Research

• Will contribute to two Master of Science theses (both still in process) • Snyder, C. MS, Conservation Biology, SUNY ESF. Expected completion Fall 2011. • Yantachka, J. MS, Conservation Biology, SUNY ESF. Expected completion Spring 2013.

• Scientific talks, including invited seminars and national conferences: • Beier CM. 2010. Sustainability science in forest landscapes. Cary Institute of Ecosystem Studies Seminar Series, Millbrook, NY. Invited talk. • Beier CM, Woods AM, Hotopp K, Mitchell MJ, Gibbs JP, Dovciak M, Leopold DJ, Lawrence GB, Page B. 2010. Soil calcium shapes communities across multiple trophic levels in Adirondack northern hardwood forests. Northeastern Ecosystem Research Cooperative (NERC) 2010 Conference, Saratoga Springs, NY. • Beier CM. 2010. Calcium, acid rain and forest biodiversity in the Adirondacks. Biology Seminar Series – Colgate University, Hamilton, NY. Invited talk. • Beier CM, Woods AM, Hotopp K, Mitchell MJ, Gibbs JP, Dovciak M, Leopold DJ, Lawrence GB, Page B. 2010 Variability in land snail and amphibian communities along a soil calcium gradient in upland hardwood forests of the Adirondack Mountains, NY. Ecological Society of America 2010 Annual Meeting, Pittsburgh, PA. List of Products

• Grants leveraged from this NSRC Theme Four support include: • Beier CM, Gibbs JP, Mitchell MJ, Dovciak M and Fierke M. Impacts of acidic deposition and soil calcium depletion on terrestrial biodiversity and food webs in northern hardwood forest ecosystems. Northeastern States Research Cooperative (NSRC) Theme Two - $141,488. 09/01/2010-08/31/2013 • Yantachka J and Beier CM. Effects of acidic deposition on songbird abundance and diversity in the Adirondack Mountains, New York. Audubon New York - Cullman Conservation Foundation Research Grant - $3,769. 06/01/2011-05/31/2012

• Proposals pending, leveraged from this NSRC support, include: • Pabian S. From soils to songbirds: the trophic movement of calcium, aluminum, and mercury in forest ecosystems impacted by air pollution. National Science Foundation Postdoctoral Research Fellowship. Expected decision by June 2011.

• Georeferenced (mapped) site-level raw data, analysis outputs and photos will be available on our web-based GIS mapping portal (www.aprgis.org) as of June 2011

• Selected site-level data will also be contributed to the Northeastern Ecosystem Research Cooperative’s online database, as requested, by June 2011