Susan Will-Wolf

Repeatability of Community Data: Species Richness Versus Gradient Scores in Large-scale Lichen Studies

Repeated ecological assessments based on permanent plot data require sufficient data quality to detect a signal of change against a background of noise (sampling error of various kinds). We analyzed several components of error in the time-constrained method for sampling lichen communities used by the Forest Health Monitoring program: between-crew (Technicians), crew-to-expert, between-expert, and seasonal variation. Data were from the southeastern United States and Oregon. Two types of dependent variables were used: species richness and scores on lichen community gradients (responses to climatic and air quality gradients). Gradient scores were repeatable to within 2-10% for experts and technicians alike and did not differ between those groups. Species richness is much more difficult to estimate reliably. Despite relatively low species capture by technicians, the high repeatability in gradient scores demonstrates the statis- tical redundancy in information provided by various lichen species. These results imply that re- peated assessments of species richness will contain considerable observer error, but that shifts in community composition may nevertheless be detected reliably.

LAND USE, WATER CHEMISTRY, AQUATIC VEGETATION, AND ZOOPLANKTON COMMUNITY STRUCTURE OF SHALLOW LAKES

Landscape-lake interactions, including anthropogenic effects in modern hu- man-dominated landscapes, are essential elements of our understanding of aquatic com- munity ecology. This study links land use (six categories) to the aquatic environment (30 water chemistry, lake morphology, and vegetation variables) and to zooplankton community richness (32 common taxa) and composition in 73 small and shallow lakes of southeastern Wisconsin, USA. The sites differed most according to two environmental variables (prin- cipal components analysis (PCA) ordination): the presence/absence of riparian vegetation and the water source (whether ground or atmospheric). Shallow lakes in different land use categories (reference, urban, and agricultural) differed significantly in terms of the two major environmental variables, especially presence of riparian and aquatic vegetation. Reference sites were characterized by the most vegetation and the highest zooplankton richness. Agricultural sites with wide riparian vegetative buffer strips (>30 m) had sig- nificantly more zooplankton taxa than agricultural lakes with narrow buffer strips. A non- metric multidimensional scaling (NMS) ordination of zooplankton community composition suggested a single community among land use categories, with some variation related to vegetation and the water source. The first NMS axis was correlated with PCA1 axis (veg- etation) and with zooplankton taxon richness, and the second axis was correlated with PCA2 (water source). The third axis was not strongly correlated with any of the measured en- vironmental factors, suggesting that an unmeasured factor related to disturbance was also important in determining taxon composition. Our analysis supports the hypothesis that zooplankton community structure (taxon richness and composition) is indirectly associated with land use, via the effect of land use on vegetation and the hydrological continuum.

Monitoring Biodiversity And Ecosystem Function: Forests

Scientists and land managers have been concerned about the state of forest lichens for many years. Most of the studies published during the last 100 years on lichens and pollution (e.g. reviews [49, 65] and section 1, this volume) have involved lichens on trees, and many studies have investigated forest lichen communities. In the last 50 years, concern about the loss of lichen diversity in connection with forest management and forest fragmentation has led to many studies designed to assess patterns and monitor trends of lichen biodiversity in forests worldwide (e.g. reviews [2, 82]). Recognition of the regional, continent-wide, and even global scale of adverse impacts on lichen communities has fostered studies and monitoring efforts designed to assess the impact of multiple factors adversely affecting forest lichen communities at large scales [43].

Status and future of the forest health indicators program of the USA

For two decades, the US Department of Agriculture, Forest Service, has been charged with implementing a nationwide field-based forest health monitoring effort. Given its extensive nature, the monitoring program has been gradually implemented across forest health indicators and inventoried states. Currently, the Forest Service’s Forest Inventory and Analysis program has initiated forest health inventories in all states, and most forest health indicators are being documented in terms of sampling protocols, data management structures, and estimation procedures. Field data from most sample years and indicators are available on-line with numerous analytical examples published both internally and externally. This investment in national forest health monitoring has begun to yield dividends by allowing evaluation of state/regional forest health issues (e.g., pollution and invasive pests) and contributing substantially to national/international reporting efforts (e.g., National Report on Sustainability and US EPA Annual Greenhouse Gas Estimates). With the emerging threat of climate change, full national implementation and remeasurement of a forest health inventory should allow for more robust assessment of forest communities that are undergoing unprecedented changes, aiding future land management and policy decisions.

Methods for Monitoring Biodiversity and Ecosystem Function

In this chapter we review strategies for monitoring lichen biodiversity and for monitoring ecosystem function with lichens. Concern about threats to lichen biodiversity worldwide has led to increased interest in monitoring the status of lichens and assessing threats (e.g. reviews [1, 32]). The word “health” referring to the degree of maintenance of normal, natural ecosystem function, as in “forest health” or “ecosystem health”, is widely used and accepted in some parts of the world (e.g. [17]), but not in others, so we use the phrase “ecosystem function” for the concept in this chapter. For monitoring of ecosystem function, we focus on methods that can be applied on broad scales and/or to detect responses to multiple causes other than point-source pollution. This chapter is intended to complement the detailed discussion by Ferretti and Erhardt (chapter 9, this volume) of issues in the design of monitoring programs to assess pollution response of lichens. Most of that discussion is relevant to our focus, and our discussion builds on that chapter.

Multiclavula ichthyiformis (Fungi: Basidiomycota: Cantharellales: Clavulinaceae), a remarkable new basidiolichen from Costa Rica

The new basidiolichen Multiclavula ichthyiformis Nelsen, Lücking, Umaña, Trest & Will-Wolf is described from Costa Rica. The new species differs from other species of Multiclavula in having a basidiocarp with tomentose stipe and flattened lamina with nonamphigenous hymenium. Molecular sequence data (ITS) confirmed its placement within Multiclavula in the Clavulinaceae (Cantharellales, Agaricomycetes). The new lichen was discovered in a Central American paramo remnant, illustrating the importance of biotic inventories of fungi and lichens to increase our knowledge of the diversity of these groups in endangered tropical ecosystems. The new species was found as part of the TICOLICHEN project in Costa Rica.

Erratum to: Evaluation of traditionally circumscribed species in the lichen-forming genus Usnea , section Usnea (Parmeliaceae, Ascomycota) using a six-locus dataset

The MycoBank code of the newly described species Usnea parafloridana was missing. The MycoBank code for the species Usnea parafloridana should read: MB818694. Usnea parafloridana K. Mark, Will-Wolf & Randlane sp. nov.; MycoBank No. MB818694. Type: USA, Wisconsin, Vilas Co., Trout Lake Conifer Swamp State Natural Area; 46.0135° N, -89.6586° W; 27.08.2011, Susan Will-Wolf WW14807: isolates WW_018 (holotype, TU; Fig. 4a, c, e), WW_023 (isotype 1, WIS), WW_013 (isotype 2, F). Morphology: thallus shrubby, up to 3–6 cm long, often with relatively few branches; branching mainly isotomic-dichotomous, divergent; lateral branches not narrowed at point of attachment; basal part distinctly jet black, with few annular cracks; papillae verrucose, numerous on main branches and lesser or absent on lateral branches; fibrils few to numerous; soralia small and punctiform when young, enlarging, becoming close to each other but usually staying delimited when mature, more numerous on terminal branches; isidiomorphs numerous, spinulose, relatively short and thick, both on young and mature soralia; cortex thick (9–15%); medulla thin (10.5– 13%), dense, not pigmented; central cord thick (60–73%) and white; apothecia not seen (Fig. 4; colour illustrations in online version). Secondary chemistry: usnic acid in cortex; norstictic acid as a major compound, salazinic acid as an accessory substance (present in most examined specimens) in medulla. Ecology: on branches of Abies balsamea, Larix laricina, Picea mariana, or Pinus strobus in cedar swamp, conifer bog and pine plantation with trees over one-hundred years old. Distribution: currently 15 specimens are known from four localities in Wisconsin, USA. Etymology: the species is morphologically somewhat similar to Usnea subfloridana (both taxa have similar shrubby thalli, black basal parts and delimited soralia with numerous isidiomorphs), which phylogenetically appears conspecific with U. florida. The same root ‘florida’ is used in the epithet of the new taxon to underline this morphological similarity while the prefix ‘para-‘ indicates phylogenetic distinctness of the species from U. florida and U. subfloridana. The online version of the original article can be found at http://dx.doi. org/10.1007/s13127-016-0273-7.

Lichen-based indices to quantify responses to climate and air pollution across northeastern U.S.A

Abstract Lichens are known to be indicators for air quality; they also respond to climate. We developed indices for lichen response to climate and air quality in forests across the northeastern United States of America (U.S.A.), using 218–250 plot surveys with 145–161 macrolichen taxa from the Forest Inventory and Analysis (FIA) Program of the U.S. Department of Agriculture, Forest Service. Lichen indicator species for response to climate and air quality were selected using Indicator Species Analysis, correlations with environmental variables, and published literature. Ordinations were used to evaluate the strength and relationships of the final indices. The Pollution Index was calculated for a plot from abundances of 12 tolerant and 45 sensitive indicator species standardized by abundance of all lichen species. The Index was correlated with modeled deposition of acidifying sulfur and oxidized nitrogen and with lichen community ordination pollution axes. Analyses suggested separate response of lichens to fertilizing N (weak statistical support). The Climate Index, from abundances of 19 warmer and 47 cooler climate indicator species, was correlated with modeled minimum January and annual maximum temperatures, and with ordination climate axes. The two indices are statistically independent. Repeat sample variability for each index was 7–14.5% (lower with higher quality data), supporting detection of consistent trends of 16–20% change over time or variation across space. Variability of the Climate Index was more affected by data quality than that of the Pollution Index. The continuous gradient of Pollution Index values suggests the cleanest areas may have air pollution above a critical load to fully protect lichen communities. These Indices can be applied to track lichen responses using other data from our study regions; suitability should be tested before use outside of the study area.

Element analysis of two common macrolichens supports bioindication of air pollution and lichen response in rural midwestern U.S.A

Abstract Element analysis was conducted on naturally-growing Flavoparmelia caperata (L.) Hale and Punctelia rudecta (Ach.) Krog (26 sites) in 2003–05 for a 30-year resurvey of forest lichen communities near a power plant in Wisconsin. Cu, Cr, N, and S increased strongly with power plant impact (66 samples, both species) and are good candidate bioindicators for local pollution; Al and Fe increased weakly and are not recommended. Hg is a candidate pollution indicator from comparison with a background site (only F. caperata data: 39 samples, 23 sites). Only N and S were correlated with lichen species abundance and are thus candidate bioindicators for lichen response. Abundance of P. rudecta was lower and that of Phaeophyscia pusilloides (Zahlbr.) Essl. was higher with more N or S in lichens; abundances of F. caperata and large foliose species as a group were lower with higher modeled SO2 from the power plant (no response from four other tested lichen species or groups). Sites in more forested landscapes to the west of the power plant had more lichen species, including disturbance-sensitive taxa. Heathier lichens there may have led to higher concentrations of Al, Cr, and S, plus Li (only F. caperata data). Univariate general linear modeling (GLM) was more useful than regression to test species effect at 7 sites. Element analysis confirmed earlier records of minimal power plant impact on lichens in this area, where no truly pollution-sensitive lichen species have been recorded for decades.

Potential impacts of UV exposure on lichen communities: a pilot study of Nothofagus dombeyi trunks in southernmost Chile

Abstract High‐latitude terrestrial ecosystems face the triple threats of climate warming, increased exposure to UV arising from polar ozone depletion, and deforestation. Lichen communities of southernmost Chile are recognized for their high diversity, which includes nitrogen‐fixing cyanolichens. Such lichens are common on forest trees, contribute nitrogen to forests, and are sensitive to exposure following deforestation (widespread in this region). In a pilot study of exposure effects on tree lichens, using nondestructive imaging methods, we compared lichen communities on trunks of isolated vs. forest tree trunks of southern Chilean beech (Nothofagus dombeyi, Nothofagaceae). We chose trees of similar diameter and trunk lean angle in conserved forest and nearby logged meadow on Navarino Island, XII Region Magallanes and Chilean Antarctica, Chile, within the annual southern ozone hole. Ninety‐five percent of cyanolichen records, including Nephroma antarcticum, and 66% of records for other foliose lichens were from the forest, whereas pendulous usneoid lichens dominated N. dombeyi bark at the meadow site. Limitation of cyanolichen growth on isolated trees could affect ecosystem function in this poorly studied habitat. Possible factors contributing to strong community differences were increased light intensity, UV radiation, and wind stress, plus limited ability of lichens to colonize isolated trees in the logged meadow. UV radiation was likely an important stressor for some lichen species but not others. We recommend more extensive monitoring to pinpoint causes of differing lichen communities, and we encourage better protection of bark‐dwelling lichens in southern hemisphere regions facing multiple threats.