Earthworms from soils developed after 80 years under tree monocultures at Holt Down, Hampshire, UK

Experimental research from the 1980s showed that tree species influenced soil development where stands of beech (Fagus sylvatica) and small-leaved lime (Tilia cordata) respectivey started to develop a podzolic soil and a brown forest soil after 50 years from near identical origins. Evidence of earthworms was reported but no detail provided. Current work re-examined these soils and a further adjacent spruce (Picea abies) plantation and specifically sampled for earthworms. Standard soil and litter measurements were made, and earthworms were collected by a combined digging and hand-sorting, plus vermifuge technique. The soil surface below lime was covered with Mercurialis perennis, but deep leaf litter was present below beech, with needle cover below spruce. Significantly more earthworms were present below lime, at a density of 29 m−2, when compared with beech (<2 m−2) with spruce intermediate (11 m−2), with a significantly greater earthworm biomass below lime. Of 8 earthworm species collected, more than 70% were from below lime, including Aporrectodea longa, Lumbricus terrestris, A. caliginosa, Octolasion cyaneum and L. rubellus. Those below spruce were mainly Dendrobaena octaedra and only A. longa was found below beech. These observations, after 80 years of differential soil development below tree stands, clearly show continued interactive influences on soils of monoculture tree species with associated ecosystem engineering earthworms

Temperature Affects Hatching Success of Cocoons in the Invasive Asian Earthworm Amynthas agrestis from the Southern Appalachians

Invasive Asian earthworms are increasingly common in the eastern USA where they are a major cause of terrestrial ecosystem disturbance. Among these, Amynthas agrestis (Crazy Worm, Alabama Jumper, and other common names) has been shown to alter above- and belowground food webs. Life-history traits of these earthworms are largely unknown, particularly in their invaded range. Here, we sought to answer questions about temperature effects on hatching success for cocoons of this species, using specimens collected from the southern Appalachian Mountains. We conducted 2 experiments investigating the effects of incubation temperature and the effect of varying the duration of cold temperature on hatching success. Of the temperatures tested, we found that cocoons hatched with greatest success at 10 °C, but our tests indicate a long duration at that temperature may be needed to result in an increase in hatching success. These results indicate that temperature and the duration of temperature exposure affect hatching success in this species. While our results contribute to the growing body of knowledge about the life-history traits of invasive Asian earthworms in the eastern US, more research is needed to provide a finer-resolution understanding of the optimum level and duration of temperatures for hatching success of A. agrestis

Periodical cicada emergence resource pulse tracks forest expansion in a Tallgrass prairie landscape

Understanding factors that influence resource pulses is an important aspect of ecosystem ecology. We quantified below‐ to aboveground energy and nutrient fluxes during the 2015 periodical cicada emergence from forest habitats in a tallgrass prairie matrix and compared results to our prior studies of the 1998 emergence in the same watershed. We estimated 35.2 million cicadas emerged across 159 ha in 2015, almost 2× more than the 19.6 million across 98 ha in 1998. The 2015 emergence resulted in below to aboveground fluxes of 9.4 metric tons of ash‐free dry mass and 1.12 metric tons of N, both ~2× greater than 1998. This corresponds to 59 kg C/ha and 7 kg N/ha in and adjacent to forested areas in 2015. Increased emergence in 2015 was a result of spatial expansion of cicadas, not higher densities. Periodical cicadas are expanding with forest habitats in this region. Cicadas expand into and oviposit in ~40% of available forest habitat during each emergence. Accordingly, we predict the 2032 emergence will span ~245 ha. Our study demonstrates how human alterations to a landscape, in this case forest expansion linked to fire suppression and reduced grazing, can alter the magnitude and extent of a resource pulse

Action of earthworms on flint burial – a return to Darwin’s estate

For thirty years, from the early 1840s, Charles Darwin documented the disappearance of flints in the grounds of Down House in Kent, at a location originally known as the “Stony Field”. This site (Great Pucklands Meadow - GPM) was visited in 2007 and an experiment set up in this ungrazed grassland. Locally-sourced flints (either large - 12 cm, or small – 5 cm dia.) were deposited at two densities within sixteen 1 m2 plots in a randomised factorial design. The area selected was distant from public access routes and remained unmown throughout the duration here reported. Fixed point photographs were taken at the outset to enable later photogrammetric analysis. After 6 years, the site was re-examined. The flints had generally been incorporated into the soil. Photographs were re-taken, proportion of buried flints recorded and measurements made of burial depth from a quarter of each plot. Results showed that large flints were more deeply incorporated than smaller (p=0.025), but more of the latter were below the soil surface. A controlled laboratory experiment was also conducted using Aporrectodea longa (the dominant earthworm species in GPM) to assess effects of casting in the absence of other biota. Results suggested that this species has a major influence on flint burial through surface casting. Combined with a long term, but small scale collection of A. longa casts from an area close to GPM, all results were consistent with those provided by Darwin and showed that rate of flint burial was within the range 0.21-0.96 cm y-1

Deep Ion Torrent sequencing identifies soil fungal community shifts after frequent prescribed fires in a southeastern US forest ecosystem

Prescribed burning is a common management tool to control fuel loads, ground vegetation, and facilitate desirable game species. We evaluated soil fungal community responses to long-term prescribed fire treatments in a loblolly pine forest on the Piedmont of Georgia and utilized deep Internal Transcribed Spacer Region 1 (ITS1) amplicon sequencing afforded by the recent Ion Torrent Personal Genome Machine (PGM). These deep sequence data (19,000+ reads per sample after subsampling) indicate that frequent fires (3 year fire interval) shift soil fungus communities whereas infrequent fires (6 year fire interval) permit system resetting to a state similar to that without prescribed fire. Furthermore, in nonmetric multidimensional scaling analyses, primarily ectomycorrhizal taxa were correlated with axes associated with long fire intervals whereas soil saprobes tended to be correlated with the frequent fire recurrence. We conclude that 1) multiplexed Ion Torrent PGM analyses allow deep cost effective sequencing of fungal communities, but may suffer from short read lengths and inconsistent sequence quality adjacent to the sequencing adaptor; 2) frequent prescribed fires elicit a shift in soil fungal communities; and, 3) such shifts do not occur when fire intervals are longer. Our results emphasize the general responsiveness of these forests to management, and the importance of fire return intervals in meeting management objectives

Tools for monitoring and study of peregrine pheretimoid earthworms (Megascolecidae)

Peregrine pheretimoid earthworms, commonly known as jumping worms, are members of the family Megascolecidae that have become widely established outside of their native ranges. In many parts of the world this represents a second wave of earthworm invasions, following the introduction of peregrine European earthworms in the family Lumbricidae during the colonial era. Forest ecologists, turf managers, gardeners, and other land managers are concerned about the observed or presumed negative effects of jumping worms on invaded habitats. Although research on jumping worms has accelerated in recent decades, our understanding of their ecology remains limited. We compiled techniques useful to researchers working to fill voids in our understanding. Similar past efforts have focused on tools used to study common European species. Differences in life cycle, behavior, morphology, and physiology make it difficult to transfer experiences with European earthworms to pheretimoids. For example, the loss of reproductive features in many pheretimoid populations poses a challenge for identification, and techniques for individually tagging lumbricid earthworms have been less successful for megascolecids. The active and ongoing expansion of pheretimoid populations in many areas requires increased attention on distributed methods, such as citizen-science protocols, for detecting and tracking their expansion. Finally, the desire to limit populations of pheretimoids, including those invading gardens and other environments that might be successfully restored, has exposed the lack of options for targeted, effective control of unwanted earthworms. We identify opportunities to address these voids in our methodological tool kit and encourage the adaptation of techniques previously used in the study and management of other invasive animals

Data Archival for Fire Studies in the Coastal Plain, Piedmont, and Southern Appalachian Mountains

Datasets from on-going and previous fire studies in the Coastal Plain, Piedmont, and Southern Appalachian regions in the southeastern U.S. dating back over the past 50 years were compiled and publically made available to other interested persons. The projects included for this data archival have helped to advanced fire science and provided much needed information about fire effects on ecosystem components. The research from these projects has demonstrated how returning fire to once fire-adapted communities is an on-going process that needs to be repeated frequently. They also have given some insight into alternative treatments that may be used for fuel reduction, depending on land managers’ objectives, and the ecological effects that may be associated with alternative treatment. The commonalities between these studies both in variables measured and site locations provide data that allow a more complete view of these ecosystems providing a unique opportunity for meta-analysis of multiple fires and other fuel reduction treatments at regional levels. Datasets from 7 different studies were selected to provide information pertaining to fire and/or fuel treatment effects on vegetation, fuels, and soils: 1) prescribed burning for stand replacement in Table Mountain pine stands in the southern Appalachian Mountains; 2) consequences of fire and fuel reduction treatments in the Piedmont and Coastal Plain; 3) fuel classification by landscape position in the southern Appalachians; 4) fuel decomposition rates by landscape position in the Southern Appalachians; 5) prescribed burning and release of mercury; 6) long-term winter-burning effects on vegetation and soils in the Coastal Plain; and 7) season of burn and fire return interval effects on vegetation and soils in the Piedmont. Five of these studies can be considered as long-term projects with sampling occurring over 8-24 years (with one study encompassing 50+ years), whereas the other 2 studies were 2-5 year projects. Each dataset and its variables are found in Table 1

Teacher-Student Water Quality Trend Monitoring: An Investment in Sustaining Water Quality in Georgia

Proceedings of the 1995 Georgia Water Resources Conference, April 11 and 12, 1995, Athens, Georgia.This paper describes a program that trains teachers to conduct trend monitoring research projects with their students. This project is important because it provides citizen awareness on the part of both teachers and students and introduces students to a variety of careers in fields related to water resources management. More important yet, it improves both basic science education and the understanding of the relationship and importance of science in resource management and public policy.Sponsored and Organized by: U.S. Geological Survey, Georgia Department of Natural Resources, The University of Georgia, Georgia State University, Georgia Institute of TechnologyThis book was published by the Carl Vinson Institute of Government, The University of Georgia, Athens, Georgia 30602 with partial funding provided by the U.S. Department of Interior, Geological Survey, through the Georgia Water Research Institute as authorized by the Water Resources Research Act of 1990 (P.L. 101-397). The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of the University of Georgia or the U.S. Geological Survey or the conference sponsors

Observations on an epilobic Lumbricus rubellus (Oligochaeta, Lumbricidae) from the Great Smoky Mountains National Park, Tennessee, USA

Carrera-Martínez, Roberto, Callaham, Mac A. (2018): Observations on an epilobic Lumbricus rubellus (Oligochaeta, Lumbricidae) from the Great Smoky Mountains National Park, Tennessee, USA. Zootaxa 4496 (1): 411-413, DOI: https://doi.org/10.11646/zootaxa.4496.1.3