Recipient Organization
CONNECTICUT AGRICULTURAL EXPERIMENT STATION
PO BOX 1106
NEW HAVEN,CT 06504
Performing Department
Forestry & Horticulture
Non Technical Summary
Our earlier work on tree dynamics based on individual tree characteristics, species functional characteristics, and stand age will be extended to examine ninety years of change. These models will be refined by incorporating detailed topographic and edaphic data collected in collaboration with USDA-NRCS, effects of conspecific and total neighborhood density, and impact of annual soil moisture fluctuations. Examining the impact of soil moisture on individual stem growth and mortality is crucial because of the predicted fluctuations in annual precipitation extremes related to climate change. In addition, we will examine the effects of habitat factors and disturbance on spatio-temporal changes in community composition using repeated measurement analysis of variance and multivariate ordination techniques. This project will increase our understanding of temperate deciduous forest dynamics in general, and those of eastern North America specifically.The lower, but not insignificant, species richness of a temperate deciduous forest allows for more simplified models of forest stand dynamics to be developed and validated before extension into extremely complex and species rich tropical forests. Using the exceptionally long-term data set of the Old-Series tracts, we will integrate the approaches of both ecology and forestry disciplines to understand the relative importance and interaction of causal factors influencing individual tree development. Understanding the aggregate behavior of individual stems will increase our comprehension of the causal mechanism(s) driving forest stand development and of the reaction of forests to exogenous disturbance including eruption of a destructive non-native pest. Perhaps as important, this study provides an opportunity to examine alternative modes of analyzing multi-decadal data of individual tree growth, including effects of unanticipated disruptive events such as non-native pests. Thus, an early examination of analytical techniques for long-term data will become increasingly useful as additional data are collected on recently established plots such as most CTFS-ForestGEO sites.
Animal Health Component
15%
Research Effort Categories
Basic
70%
Applied
15%
Developmental
15%
Goals / Objectives
As with the shift from chestnut to oak forests in the early 1900s, the emergence of a forest dominated by mesophytic hardwoods will alter the economic, ecological, and esthetic values of the forest. The consequences of these changes will last well into the 21st century. Historically, oak has been more economically valuable than maple and birch for its higher price, lower cull rates, and higher per acre volume growth. The shift from oak will also affect many wildlife and insect populations - discriminating against those species dependent on oak and favoring those species associated with maple and birch. Changes in esthetic values are important because of increased public use of the forested landscape for both home sites and recreation.The lower, but not insignificant, species richness of a temperate deciduous forest allows for more simplified models of forest stand dynamics to be developed and validated before extension into extremely complex and species rich tropical forests. Using the exceptionally long-term data set of the Old-Series tracts, scientists at The Connecticut Agricultural Experiment Station, in collaboration with others, will integrate the approaches of both ecology and forestry disciplines to understand the relative importance and interaction of causal factors influencing individual tree development. Understanding the aggregate behavior of individual stems will increase our comprehension of the causal mechanism(s) driving forest stand development and of the reaction of forests to exogenous disturbance including eruptions of destructive non-native diseases and pests such as gypsy moth.The overall objective of our research is to develop a model of forest stand dynamics based on the aggregate development of individual trees. Results from the analyses of specific objectives listed below will be integrated into an interactive model to examine the sensitivity of stand development trajectories to different initial stand composition and structure, edaphic factors, and disturbance regimes. The specific objectives are independent of each other. Specific objectives for individual species are to determine how survival, movement among crown classes (canopy strata), upper canopy residency rates, and diameter growth during stand development are influenced by: initial tree metrics, stand disturbance, edaphic factors, and neighborhood density. Specific stand level objectives are to determine the effects of disturbance and site factors on spatio-temporal changes in community composition using repeated measurement analysis of variance to examine trends of population level changes in abundance metrics.
Project Methods
Individual species - for the 24 tree and 8 shrub species with at least 150 stems, determine how survival, movement among crown classes (canopy strata), upper canopy residency rates, and diameter growth during stand development are influenced by:Initial tree metrics (e.g., crown class, diameter) - The procedures used in examining 70-year development of selected species (Ward et al. 1999) will be extended to 100 years. More recently, these procedures have been used to examine 25 years of canopy stratification in sapling stands (Ward 2017).Stand disturbance - Procedures used to examine the effects of disturbance on recruitment, growth, and mortality (Ward and Stephens 1989,Ward 2013) will be used and expanded upon to determine legacy effects through 100 years. Our 1:24000 aerial maps of extent and degree of defoliation on the study tracts will be digitized to assign cumulative decadal area estimates of defoliation to individual stems.Conspecific and total neighborhood density -We have previous experience examining the effect of neighborhood density on recruitment (Ward and Parker 1989, Ward et al. 1996), mortality (Ward et al. 1996), and estimates of spatial distribution. Updated analytical methods will be used to examine neighborhood effects on stand development and diversity (Piao et al. 2013, Wills et al. 2016, Wu et al. 2016).Edaphic factors - This will be completed in collaboration with USDA NRCS-Connecticut who will create GIS layers of topographic characterizations using Lidar data and detailed soil mapping on the study tracts. NRCS will also use the collected data in the development of their ecological site descriptions.Stand level - each of the 550 transect segments (each 100 m2) across the four tracts will be assigned (1) cumulative decadal area estimates of defoliation as noted above and (2) topographic and edaphic values derived using the USDA NRCS-Connecticut developed GIS layers also noted above. The effects of disturbance and site factors on spatio-temporal changes in community composition will be examined using:Abundance - Repeated measurement analysis of variance will be used to examine trends of population level changes in abundance metrics (e.g., density, basal area, and aboveground biomass) of both surviving and ingrowth stems for individual and combined species. This will extend an earlier 80 year analysis of general disturbance types on basal area and ingrowth at coarse spatial scales (Ward 2013) to a finer-scale 90 year analysis that incorporates site factors.ProceduresThe first three specific objectives will be accomplished by using data collected using methodologies of the previous eight inventories (1926-27 - 2007) and the planned survey of 2017 (Ward et al. 1999). The other two objectives will be accomplished in planned collaboration with USDA NRCS-Connecticut. During the ninth decadal survey of these tracts in 2017, woody vegetation data will be collected on all 550 transect segments (each 100 m2) using historic standards of this study as summarized below and in detail in the Appendix.A special concern of long-term studies is maintenance of data quality, i.e., consistency of data measurements and methods. Transect locations were permanently established in 1926 with rock cairns and wooden stakes that were replaced by metal bars. We have retained all original field data sheets. In addition, the continuity with overlapping principal investigators is unique for a study of this length: H.W. Hicock (1927-1957), G.R. Stephens (1957-1987), and J.S. Ward (1987-present).For all stems with diameters at least 1.2 cm at 1.37 m aboveground, data to be recorded will include: location, species, diameter, crown class (canopy position), and whether the stem is part of a sprout clump. Beginning in 1967, additional information has been collected to estimate aboveground biomass growth. These measurements will be repeated on the same 10% subset of stems used in earlier surveys. Dead stems will also be measured, but new live stems will be randomly assigned to maintain sample pool size. On a 1/1000-ha plot halfway between stations record all species, height class, and density of all tree seedlings less than 1.2 cm dbh; and record cover estimates of all shrub species.Piao, T., L.S. Comita, G. Jin, and J.H. Kim. 2013. Density dependence across multiple life stages in a temperate old-growth forest of northeast China. Oecologia 172:207-217. DOI 10.1007/s00442-012-2481-yWard, J.S., S.L. Anagnostakis, and F.J. Ferrandino. 1999. Seventy years of stand dynamics in Connecticut hardwood forests - the Old-Series plots (1927-1997). The Connecticut Experiment Station Bulletin 959 68p.Ward, J.S., and G.R. Parker. 1989. Spatial dispersion of woody regeneration in an old-growth forest, Indiana, USA. Ecology. 70: 1279-1285.Ward, J.S., G.R. Parker, and F.J. Ferrandino. 1996. Long-term spatial dynamics in an old-growth deciduous forest. Forest Ecology and Management 83: 189-202.Ward, J.S., and G.R. Stephens. 1989. Long-term effects of a 1932 surface fire on stand structure in a Connecticut mixed-hardwood forest. P.267-273 in Proceedings of the Seventh Central Hardwood Conference. USDA Forest Service General Technical Report NC-132. 304 p.Ward, J.S., and G.R. Stephens. 1996. Influence of crown class and survival and development of Betula lenta in Connecticut, USA. Canadian Journal of Forest Research 26: 277-288.Ward, J.S. 2013. Influence of disturbance on stand development during deciduous forest succession in Connecticut. P. 93-104 In Proceedings 18th Central Hardwood Conference. USDA Forest Service General Technical Report NRS-P-117. 531 p. [CD-ROM].Ward, J.S. 2017. Twenty-five year response of non-crop trees to partial release during precommercial crop tree management. Forest Ecology and Management 387: 12-18. http://dx.doi.org/10.1016/j.foreco.2016.05.036Wills, C., K.E. Harms, T. Wiegand, R. Punchi-Manage, G.S. Gilbert, D. Erickson, W. Kress, S.P. Hubbell, C.V.S. Gunatilleke, I.A.U.N Gunatilleke. 2016. Persistence of neighborhood demographic influences over long phylogenetic distances may help drive post-speciation adaptation in tropical forests. PLoS ONE 11(6): e0156913. doi:10.1371/journal.pone.0156913Wu,J., N.G. Swenson, C. Brown, C. Zhang, Ji. Yang, X. Ci, J. Li, L. Sha, M. Cao, and L. Lin. 2016. How does habitat filtering affect the detection of conspecific and phylogenetic density dependence? Ecology 97(5): 1182-1193.