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Long-term monitoring of ground-dwelling arthropods in the McDowell Sonoran Preserve, Scottsdale, Arizona (2012-2025)

*Project overview* Protected lands, such as the McDowell Sonoran Preserve (hereafter referred to as the Preserve) in Scottsdale, Arizona, provide critical refuge for native biota and natural, ecological processes within and near urban environments. At the same time, a key feature that makes urban, open-space preserves so valuable − their proximity to urban areas − places strain on the ecological integrity of these systems through visitation, habitat fragmentation, and the introduction of exotic species among others. Effective management of these systems requires detailed knowledge of the biota within the protected area, and monitoring of ecological indicators through time. Arthropods are well suited to monitoring ecological health. This diverse group of organisms typically reflects overall biological diversity of a system, and includes several trophic levels; their short generation times mean they will likely respond quickly to change; and they are relatively easy to sample. As part of a broad effort by the McDowell Sonoran Conservance Field Institute, an organization that oversees science and research in Preserve, to establish a baseline inventory of biota in the Preserve, investigators with the Central Arizona−Phoenix Long-Term Ecological Research (CAP LTER) program at Arizona State University (ASU) in collaboration with Field Institute Citizen Scientists are monitoring ground-dwelling arthropods at select locations that reflect a diversity of habitat within the Preserve. Investigators employ a sampling design that is intended to provide insight regarding influence of the urban-wildland interface on the arthropod community within the protected area. The simple but effective technique of pitfall trapping is used to sample ground-dwelling arthropods at select locations spanning a wide range of habitat with the Preserve. Additional collections of vegetation-dwelling arthropods have been conducted at the sampling locations at periodic intervals. *Project design and sa

openCC0Jan 2024View details →

Ungulate-Disturbance Interactions in Hemlock Ecosystems at Harvard Forest 2012-2013

Densities of ungulates are often associated with recent forest disturbances such as fire, logging and insect outbreaks, as increased resources stimulate tree regeneration, leading to abundant available browse. Despite the often significant role that ungulates play in disturbed forests, surprisingly little is known about ungulate-disturbance interactions, and ungulate herbivory is often excluded from examinations of forest response to disturbance. In the Northeastern United States, a large-scale insect outbreak, the hemlock wooly adelgid (HWA), has begun to have important effects on hemlock forests both directly and indirectly (i.e., by preemptive salvage logging). No studies have examined the interactions of both moose and deer activity with these associated canopy disturbances. Our objectives are twofold: to determine (1) the response of ungulates to varying disturbance types and intensities and (2) the influence of ungulate interactions with canopy disturbance on vegetation, other biota, and ecosystem processes. We will examine the relative abundance of moose and deer in four treatments (2 replicates) at the Hemlock Removal Experiment using three indices of ungulate activity: pellet group density, evidence of past browsing on seedlings and saplings, and the occurrence of animals using game cameras. We will also monitor the response of vegetation to ungulate browsing by sampling woody and herbaceous vegetation in fenced exclosures and paired controls in disturbed and undisturbed plots.

Thresholds and Tipping Points in a Sarracenia Microecosystem at Harvard Forest 2012-2013

The primary goal of this project is to determine experimentally the amount of lead time required to prevent a state change. To achieve this goal, we will (1) experimentally induce state changes in a natural aquatic ecosystem - the Sarracenia microecosystem; (2) use proteomic analysis to identify potential indicators of states and state changes; and (3) test whether we can forestall state changes by experimentally intervening in the system. This work uses state-of-the art molecular tools to identify early warning indicators in the field of aerobic to anaerobic state changes driven by nutrient enrichment in an aquatic ecosystem. The study tests two general hypotheses: (1) proteomic biomarkers can function as reliable indicators of impending state changes and may give early warning before increasing variances and statistical flickering of monitored variables; and (2) well-timed intervention based on proteomic biomarkers can avert future state changes in ecological systems.

Mark-Recapture of Rodent and Shrew Populations in a Declining Hemlock Stand at Harvard Forest 2012

Eastern Hemlocks (Tsuga canadensis) are foundation species, which are known to have a large influence on the species composition and ecosystem dynamics. The purpose of this study was to understand how rodent species richness and composition differed among different hemlock treatments consisting of intact forest, logged forest, and invaded hemlock stands in the Harvard Forest of Petersham, MA. Sherman live traps were arranged on 7x7m grids covering 0.49ha in four different hemlock treatments that were established in 2003: 1) the logged treatment, where commercial trees were removed 2) the girdled treatment, where the hemlocks were girdled using a chainsaw, thus killing the trees, and mimicking the effects of the woolly adelgid, an invasive insect 3) the hemlock control which is where hardwoods are at least 70% hemlocks, and 4) the hardwood control, where other hardwood species are dominate. Animals were marked and recaptured from June-July. Using Schnabel methods for population estimate, there appeared to be a shift in the population from more abundant Gapper’s Red-backed vole, Clethrionomys gapperi in the logged and girdled treatments to white-footed and deer mice (Peromyscus spp) in the hemlock and hardwood control plots. This shift in population may indicate that hemlocks support Peromyscus spp over voles. The species richness and overall population dynamic of these rodents surveyed may lead to a greater understanding as to the potential affect they may have on the seed dispersal in these plots and could account for many interactions between the vegetation and the animals also present.

Modeling Impacts of Climate Change on Mangroves Worldwide 2012-2080

Given the multitude of ecosystem services provided by mangroves, it is important to understand their potential responses to global climate change. Extensive reviews of the literature and manipulative experiments suggest that mangroves will be impacted by climate change, but few studies have tested these predictions over large scales using statistical models. We provide the first example of applying species and community distribution models (SDMs and CDMs, respectively) to coastal mangroves worldwide. Species projected to shift their ranges polewards by at least 2 degrees of latitude consistently experience a decrease in the amount of suitable coastal area available to them. Central America and the Caribbean are forecast to lose more mangrove species than other parts of the world. We found that the extent and grain size, at which continuous CDM outputs are examined, independent of the grain size at which the models operate, can dramatically influence the number of pseudo-absences needed for optimal parameterization. The SDMs and CDMs presented here provide a first approximation of how mangroves will respond to climate change given simple correlative relationships between occurrence records and environmental data. Additional, precise georeferenced data on mangrove localities and concerted efforts to collect data on ecological processes across large-scale climatic gradients will enable future research to improve upon these correlative models.

Soil Characteristics in the Clearcut Site at Harvard Forest 2012

Soil properties (C:N ratio, pH, soil moisture, bulk density, litter layer thickness) were measured at the clear cut site in December 2012. Measurements were taken inside the large PVC collars that were used to measure soil respiration at the sites during the 2012 growing season. The collars were removed for storage thereafter. 15 locations in total were sampled: 3 collars were in trenched plots, and 12 on untrenched soil. Soil properties were collected in order to help interpret spatial variability in the corresponding soil CO2 fluxes measured at the site.

Specific Leaf Area in the Clearcut Site at Harvard Forest 2012

Clearcutting a forest ecosystem can result in a drastic reduction of the stand’s productivity. Despite the severity of this disturbance type, past studies have found that the productivity of young regenerating stands can quickly rebound, approaching that of mature undisturbed stands within a few years. One of the obvious reasons is increased leaf area with each year of recovery. However, a less obvious reason may be the variability in species composition and distribution during the natural regeneration process. The purpose of this study was to investigate to what extent the increase in GEP, observed during the first four years of recovery, in a naturally regenerating clearcut stand was due to 1) an overall expansion of leaf area, and 2) an increase in the canopy’s photosynthetic capacity stemming from either species compositional shifts or drift in physiological traits within species. We found that the multi-year rise in GEP following harvest was clearly attributed to the expansion of leaf area rather than a change in vegetation composition. Sizeable changes in relative abundance of species were masked by remarkably similar leaf physiological attributes for a range of vegetation types present in this early successional environment. Comparison of upscaled leaf-chamber to eddy-covariance-based light-response curves revealed broad consistency in both maximum photosynthetic capacity and quantum yield efficiency. The approaches presented here illustrate how chamber- and ecosystem-scale measurements of gas exchange can be blended with species-level leaf area data to draw conclusive inferences about changes in ecosystem processes over time in a highly dynamic environment.

Litterfall in the Clearcut Site at Harvard Forest 2012

Soil Chemistry and Moisture in Macrosystems Biodiversity Project at Harvard Forest 2012

Patterns of biodiversity, such as the increase toward the tropics and the peaked curve during ecological succession, are fundamental phenomena for ecology. Such patterns have multiple, interacting causes, but temperature emerges as a dominant factor across organisms from microbes to trees and mammals, and across terrestrial, marine, and freshwater environments. However, there is little consensus on the underlying mechanisms, even as global temperatures increase and the need to predict their effects becomes more pressing. The purpose of this project is to generate and test theory for how temperature impacts biodiversity through its effect on biochemical processes and metabolic rate. A combination of standardized surveys in the field and controlled experiments in the field and laboratory measure diversity of three taxa -- trees, invertebrates, and microbes -- and key biogeochemical processes of decomposition in seven forests distributed along a geographic gradient of increasing temperature from cold temperate to warm tropical. Soil chemistry (TN, TC, NH4-N, NO3-N, and pH) and moisture measurements were taken from soil cores from an array of 21 1m2 subplots and processed by the University of Oklahoma Institute for Environmental Genomics as part of a macrosystems biodiversity and latitude project supported by the National Science Foundation under Cooperative Agreement DEB#1065836.

Soil Bacteria and Archaea in Macrosystems Biodiversity Project at Harvard Forest 2012

Patterns of biodiversity, such as the increase toward the tropics and the peaked curve during ecological succession, are fundamental phenomena for ecology. Such patterns have multiple, interacting causes, but temperature emerges as a dominant factor across organisms from microbes to trees and mammals, and across terrestrial, marine, and freshwater environments. However, there is little consensus on the underlying mechanisms, even as global temperatures increase and the need to predict their effects becomes more pressing. The purpose of this project is to generate and test theory for how temperature impacts biodiversity through its effect on biochemical processes and metabolic rate. A combination of standardized surveys in the field and controlled experiments in the field and laboratory measure diversity of three taxa -- trees, invertebrates, and microbes -- and key biogeochemical processes of decomposition in seven forests distributed along a geographic gradient of increasing temperature from cold temperate to warm tropical. This field experiment focused on soil microbes. DNA was extracted and purified from soil cores from an array of 21 1m2 subplots. The V4 region of the 16S rRNA genes for bacteria and archaea were amplified and sequenced using Illumina MiSeq by the University of Oklahoma Institute for Environmental Genomics as part of a macrosystems biodiversity and latitude project supported by the National Science Foundation under Cooperative Agreement DEB#1065836.

Soil Invertebrate Species in Macrosystems Biodiversity Project at Harvard Forest 2012

Leaf litter invertebrates and soil microbes were sampled in an array of 21 1m2 subplots by the Kaspari Ant Lab at the University of Oklahoma as part of a macrosystems biodiversity and latitude project supported by the National Science Foundation under Cooperative Agreement DEB#1065836.

Correction Factors for Dissolved Organic Carbon Extracted from Soil in New England 2012-2013

Oxidizable dissolved organic carbon (DOC) is regularly measured in environmental samples using a colorimetric method with Mn(III)-pyrophosphate as the oxidizing agent. It is simpler to use and has a much higher throughput than the commonly used dichromate oxidation and combustion methods. Here, we demonstrate that the method often leads to an underestimation or overestimation of the concentration of common organic compounds in solutions. To our knowledge, no published study has taken this fact into account when analyzing DOC data. Hence, we compared Mn(III)-pyrophosphate-based results with measurements performed with a total organic carbon combustion analyzer for samples of organic and mineral soil horizons of two temperate deciduous forests (Harvard Forest, Hubbard Brook), of organic soil horizon of a primary growth hemlock stand (Harvard Forest), and of a peatland (Caribou Bog) located in New England, USA. The Mn(III)-pyrophosphate method consistently underestimated DOC concentration in soil extracts. We present correction factors for the different types of soil studied. By employing correction factors, we find the method can be an inexpensive, accurate, and high throughput tool to measure DOC in environmental samples.

Xylem Embolism Formation, Refilling and Water Storage in Tree Trunks at Harvard Forest 2012

Trunks of large trees play an important role in whole-plant water balance but technical difficulties have limited most hydraulic research to small stems, leaves and roots. To investigate the dynamics of water-related processes in tree trunks, such as winter embolism refilling, xylem hydraulic vulnerability, and water storage, volumetric water content (VWC) in the main stem was monitored continuously using frequency domain moisture sensors in adult Betula papyrifera trees from early spring through the beginning of winter. An air injection technique was developed to estimate hydraulic vulnerability of the trunk xylem. Trunk VWC increased in early spring and again in autumn concurrent with root pressure during both seasons. Diurnal fluctuations and a gradual decrease in trunk VWC through the growing season were observed, which, in combination with VWC increase after significant rainfall events and depletion during periods of high water demand, indicate the importance of stem water storage in both short-and long-term water balance. Comparisons between the trunk air injection results and conventional branch hydraulic vulnerability curves showed no evidence of “vulnerability segmentation” between the main stem and small branches in B. papyrifera. Measurements of VWC following air injection, together with evidences from air injection and xylem dye perfusion, indicate that embolized vessels can be refilled by active root pressure but not in the absence of root pressure. The precise, continuous and non-destructive measurement of wood water content using frequency domain sensors provides an ideal way to probe many hydraulic processes in large tree trunks that are otherwise difficult to investigate.

North Temperate Lakes LTER: Northern Wisconsin Lake Resident Survey 2005, 2008, 2012

The purpose of this survey was to understand what lake characteristics people value most, what activities they enjoy most, and what they expect for the future of northern Wisconsin lakes. Questions covered aspects such as the property search process individuals went through leading up to their purchase of lakeshore property in Vilas County WI, what activities the individual's household participate in on lakes in Vilas County WI, their attitude about the future of their lake, their perception of the current state of their lake, and lake qualities they would like improved on their lake. Demographics of the respondents and background information about their lake were also collected. Two types of surveying methodologies were used for this survey, one being an internet-based survey, while the other was a mail survey. Surveys were conducted in 2005 and repeated in 2008.

WSC 2007 - 2012 Yahara Watershed surface water quality policies and practices created and implemented by public agencies

This dataset was created June 2012 - August 2013 to contribute to research under the Water Sustainability and Climate project. Interventions collected are those land-based policies and practices written and implemented by public agencies. Policies were implemented in Wisconsin's Yahara Watershed the period 2007-2012. They aim to improve surface water quality through nutrient (phosphorus and nitrogen) and sediment reduction. Interventions included in the mapping must have spatially-explicit, publicly available data through personal communication or website.

WSC - Water surface elevation (WSE) and water table depth (WTD) from 14 points at the Wibu field site, 2012-2013 growing seasons

Observation wells were installed for the purpose of continuously monitoring the water table level during the 2012 and 2013 growing seasons at the Wibu field site. These data were then used to study the yield response of corn to water table depth, soil texture, and growing season weather conditions (Zipper et al., in prep). The Wibu field site is a commercial agricultural field, which grew corn in the 2012, 2013, and 2014 growing seasons. See Zipper and Loheide (2014) Ag. For. Met. for more information about the field site. The 2012 growing season was characterized by severe drought, and the water table fell below the bottom of most wells in late June/early July.

WSC - Leaf area index (LAI) at various points within Wibu field site, 2012-2014

Leaf area index (LAI) measurements collected at various points within the Wibu field site between 2012-2014. Measurements were collected approximately weekly from plant emergence until appr. 1 month past the onset of senescence. The Wibu field site is a commercial agricultural field, which grew corn in the 2012, 2013, and 2014 growing seasons; therefore, these are all LAI values for corn. See Zipper and Loheide (2014) Ag. For. Met. for more information about the field site and use of the LAI data.

LTREB Terrestrial data 2012 - current

Pitfall traps measure the activity density of ground-dwelling arthropod communities; Infall traps measure the deposition of flying insects Sticky Cards measure the amount of flying insects with distance from the shoreline. Emergence traps measure the quantity of emerging chironomids

Long-term fish size data for Wisconsin Lakes Department of Natural Resources and North Temperate Lakes LTER 1944 - 2012 (Reformatted to the ecocomDP Design Pattern)

This data package is formatted as an ecocomDP (Ecological Community Data Pattern). For more information on ecocomDP see https://github.com/EDIorg/ecocomDP. This Level 1 data package was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/knb-lter-ntl/357/2. The abstract below was extracted from the Level 0 data package and is included for context: This dataset describes long-term (1944-2012) variations in individual fish total lengths from Wisconsin lakes. The dataset includes information on 1.9 million individual fish, representing 19 species. Data were collected by Wisconsin Department of Natural Resource fisheries biologists as part of routine lake fisheries assessments. Individual survey methodologies varied over space and time and are described in more detail by Rypel, A. et al., 2016. Seventy-Year Retrospective on Size-Structure Changes in the Recreational Fisheries of Wisconsin. Fisheries, 41, pp.230-243. Available at: http://afs.tandfonline.com/doi/abs/10.1080/03632415.2016.1160894