scholarly journals Long-term data reveal unimodal responses of ground beetle abundance to precipitation and land use but no changes in taxonomic and functional diversity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Petr Zajicek ◽  
Ellen A. R. Welti ◽  
Nathan J. Baker ◽  
Kathrin Januschke ◽  
Oliver Brauner ◽  
...  
Keyword(s):  
Land Use ◽  
Functional Diversity ◽  
Spatial Scales ◽  
Ground Beetle ◽  
Temporal Trends ◽  
Ground Beetles ◽  
Community Change ◽  
Ecological Communities ◽  
Activity Density

AbstractWhile much of global biodiversity is undoubtedly under threat, the responses of ecological communities to changing climate, land use intensification, and long-term changes in both taxonomic and functional diversity over time, has still not been fully explored for many taxonomic groups, especially invertebrates. We compiled time series of ground beetles covering the past two decades from 40 sites located in five regions across Germany. We calculated site-based trends for 21 community metrics representing taxonomic and functional diversity of ground beetles, activity density (a proxy for abundance), and activity densities of functional groups. We assessed both overall and regional temporal trends and the influence of the global change drivers of temperature, precipitation, and land use on ground beetle communities. While we did not detect overall temporal changes in ground beetle taxonomic and functional diversity, taxonomic turnover changed within two regions, illustrating that community change at the local scale does not always correspond to patterns at broader spatial scales. Additionally, ground beetle activity density had a unimodal response to both annual precipitation and land use. Limited temporal change in ground beetle communities may indicate a shifting baseline, where community degradation was reached prior to the start of our observation in 1999. In addition, nonlinear responses of animal communities to environmental change present a challenge when quantifying temporal trends.

scholarly journals Different temporal trends in vascular plant and bryophytes communities along elevational gradients over four decades of warming

2020 ◽  
Author(s):  
Antoine Becker-Scarpitta ◽  
Diane Auberson-Lavoie ◽  
Mark Vellend
Keyword(s):  
Plant Communities ◽  
Vascular Plants ◽  
Environmental Changes ◽  
Vascular Plant ◽  
Elevation Gradient ◽  
Temporal Trends ◽  
Community Change ◽  
Ecosystem Functions ◽  
Ecological Communities

Abstract1: Despite many studies showing biodiversity responses to warming, the generality of such responses across taxa remains unclear. Very few studies have tested for evidence of bryophyte community responses to warming, despite the fact that bryophytes are major contributors to diversity in many ecosystems, playing a central role in ecosystem functions. Understanding variation among taxa in their responses to warming is crucial for identifying priorities in conservation.2: We report an empirical study comparing long-term change of bryophyte and vascular plant communities in two sites with contrasting long-term warming trends. To assess long-term responses of ecological communities to warming, we used “legacy” botanical records as a baseline for comparison with contemporary resurveys.We hypothesized that ecological changes would be greater in sites with a stronger warming trends, and that vascular plant communities would be more sensitive than bryophyte communities to climate warming. For each taxon in each site, we quantified the magnitude of changes in species’ distributions along the elevation gradient, species richness, and community composition.3: Temporal changes in vascular plant communities were consistent with the warming hypothesis, but this was not the case for bryophytes. We also did not find clear support for the hypothesis that vascular plants would show greater sensitivity than bryophytes to warming, with results depending on the metric of community change. As predicted for sites with a strong warming trend, we found a significant upward shift in the distributions of vascular plants but not bryophytes.Synthesis: Our results are in accordance with recent literature showing that local diversity can remain unchanged despite strong changes in composition. Regardless of whether one taxon is systematically more or less sensitive to environmental change than another, our results suggest that vascular plants cannot be used as a surrogate for bryophytes in terms of predicting the nature and magnitude of responses to warming. In sites that experienced the same environmental changes, we found that communities of bryophytes and vascular plants did not predictably change in the same ways. Thus, to assess overall biodiversity responses to global change, data from different taxonomical groups and community properties need to be synthesized.

scholarly journals The phylogeny of Critical Zone Observatories, or how to better structure existing observation networks to match the whole system approach

2021 ◽  
Author(s):  
Isabelle Braud ◽  
Jérôme Gaillardet ◽  
François Mercier ◽  
Sylvie Galle ◽  
Virginie Entringer
Keyword(s):  
System Approach ◽  
Spatial Scales ◽  
National Level ◽  
Monitoring Network ◽  
Critical Zone ◽  
Visualization Tool ◽  
Ecological Communities ◽  
Continental Scale ◽  
Observation Networks

<p>Implementing the Whole System Approach for long-term ecosystem, critical zone and socio-ecological system research requires going beyond existing structuration of scientific communities and observation networks. Indeed, existing observation networks were often built independently from each other, on a very disciplinary basis, with their own scientific objectives, funding mechanisms and institutional constraints. To tackle the observation challenges of the “new climatic regime” in the Anthropocene, a new type of observational platforms, more compatible with a scientific systemic approach needs to be built taking into account the history and institutional contexts of long-term observatories.</p><p><br>We have attempted to represent the diversity of critical zone observatories, sites and network of observatories that exist and that have been founded by different research institutions in France over the last 40 years and that are now gathered in the OZCAR Critical Zone network. Our representation encapsulates three main characteristics: the spatial scales of investigation (from the plot scale to the continental-scale watershed), the diversity of monitored compartments (catchments, glaciers, peatlands, aquifers…), and the institutional dimension (labeling and founding at the national level).  We found that a representation in the form of a tree, mimicking the phylogenetic tree of life, named the OZCAR-tree, was offering a visualization tool able to capture the philosophy and rationale of the network and was useful to improve the communication with the neighboring infrastructures, users and stakeholders. The branches of the tree represent the nested monitored scales, with the small branches of the tree representing monitored parcels or small catchments. The trunks represent networks of sites investigating the same compartment. For monitored catchments, the representation directly shows the various sampled scales and their nested organization from upstream to downstream. At each site, colored pie charts allow us to visualize rapidly the types of data that are collected, each part of the pie being a component of the critical zone (atmosphere, soil water, aquifers, vegetation, snow, ice…). This visualization directly shows the focus of the various sites, the completeness of measurements conducted by the different scientists, but also the missing compartments. It also shows that, if the network, as a whole is able to sample the various compartments and variables required for implementing the whole system approach, it is rarely the case when considering individual sites.</p><p>Beyond being a visualization tool, the OZCAR-tree helps representing the requirements of a “whole critical zone approach”. Because all compartments of the critical zone are connected vertically and horizontally by processes and fluxes of energy and matter, the tree is meant to represent all the components to be monitored and what should be the spatial architecture of a monitoring network fulfilling the disciplinary questions and approaches. The tree is therefore an illustration of a conceptual and idealized network (devoid of cost issues) of terrestrial surfaces monitoring infrastructure respectful of disciplinary approaches.</p><p>Finally, this representation is open to ecological and socio-ecological communities and may serve as a template for fostering collaboration with ecological and socio-ecological communities and networks and implementing observation platforms at the scale of changing territories.</p>

Spatial scaling of beta diversity in the shallow-marine fossil record

Paleobiology ◽  
2020 ◽  
pp. 1-15
Author(s):  
Tom M. Womack ◽  
James S. Crampton ◽  
Michael J. Hannah
Keyword(s):  
Beta Diversity ◽  
Fossil Record ◽  
Minimum Spanning Tree ◽  
Spatial Scales ◽  
Temporal Trends ◽  
Grid Cell ◽  
Ecological Communities ◽  
Spatial Scaling ◽  
Modern Biology ◽  
Shallow Marine

Abstract Beta diversity quantifies the spatial structuring of ecological communities and is a fundamental partition of biodiversity, central to understanding many macroecological phenomena in modern biology and paleobiology. Despite its common application in ecology, studies of beta diversity in the fossil record are relatively limited at regional spatial scales that are important for understanding macroevolutionary processes. The spatial scaling of beta diversity in the fossil record is poorly understood, but has significant implications due to temporal variation in the spatial distribution of fossil collections and the large spatiotemporal scales typically employed. Here we test the spatial scaling of several common measures of beta diversity using the Cenozoic shallow-marine molluscan fossil record of New Zealand and derive a spatially standardized time series of beta diversity. To measure spatial scaling, we use and compare grid-cell occupancy based on an equal-area grid and summed minimum spanning tree length, both based on reconstructed paleocoordinates of fossil collections. We find that beta diversity is spatially dependent at local to regional scales, regardless of the metric or spatial scaling utilized, and that spatial standardization significantly changes apparent temporal trends of beta diversity and, therefore, inferences about processes driving diversity change.

Effects of crop rotation and genetically modified herbicide-tolerant corn on ground beetle diversity, community structure, and activity density

2010 ◽  
Vol 142 (2) ◽  
pp. 143-159 ◽  
Author(s):  
S. Bourassa ◽  
H.A. Cárcamo ◽  
J.R. Spence ◽  
R.E. Blackshaw ◽  
K. Floate
Keyword(s):  
Community Structure ◽  
Weed Management ◽  
Genetically Modified ◽  
Ground Beetle ◽  
Ground Beetles ◽  
Weed Density ◽  
Activity Density ◽  
Herbicide Tolerant ◽  
Pterostichus Melanarius ◽  
Structure And Activity

AbstractGround beetles (Coleoptera: Carabidae) were sampled in conventional and genetically modified herbicide-tolerant (GMHT) corn, Zea mays L. (Poaceae), planted under rotation with canola, Brassica L. (Brassicaceae), or continuously cropped corn to investigate the influence of corn variety and rotation on the structure of carabid assemblages. Corn variety, cultivation regime, and their interaction all influenced overall carabid activity density. Weed management associated with corn variety influenced the activity density of a few carabid species and this was attributed to changes in vegetation. Some smaller bodied carabids such as Bembidion quadrimaculatum L. were less abundant in GMHT plots, probably because weed density was higher in midseason, but the opposite was observed for larger bodied carabids such as Pterostichus melanarius (Illiger). Overall, rotating corn with canola had a stronger effect on carabid community structure than did corn variety. We suggest that GMHT corn has little impact on the overall carabid fauna but may influence the activity of certain species through effects on the weed community.

scholarly journals Monoculture and mixture-planting of non-native Douglas fir alters species composition, but promotes the diversity of ground beetles in a temperate forest system

2021 ◽  
Vol 30 (5) ◽  
pp. 1479-1499
Author(s):  
Peter Kriegel ◽  
Dragan Matevski ◽  
Andreas Schuldt
Keyword(s):  
Species Composition ◽  
Functional Diversity ◽  
Tree Species ◽  
Ground Beetle ◽  
Ground Beetles ◽  
Douglas Fir ◽  
Assemblage Structure ◽  
Species Identity ◽  
Native Tree ◽  
Native Tree Species

AbstractPlanting non-native tree species, like Douglas fir in temperate European forest systems, is encouraged to mitigate effects of climate change. However, Douglas fir monocultures often revealed negative effects on forest biota, while effects of mixtures with native tree species on forest ecosystems are less well understood. We investigated effects of three tree species (Douglas fir, Norway spruce, native European beech), on ground beetles in temperate forests of Germany. Beetles were sampled in monocultures of each tree species and broadleaf-conifer mixtures with pitfall traps, and environmental variables were assessed around each trap. We used linear mixed models in a two-step procedure to disentangle effects of environment and tree species identity on ground beetle abundance, species richness, functional diversity and species assemblage structure. Contradictory to our expectations, ground beetle abundance and functional diversity was highest in pure Douglas fir stands, while tree mixtures showed intermediate values between pure coniferous and pure beech stands. The main drivers of these patterns were only partially dependent on tree species identity, which highlights the importance of structural features in forest stands. However, our study revealed distinct shifts in assemblage structure between pure beech and pure Douglas fir stands, which were only partially eased through mixture planting. Our findings suggest that effects of planting non-native trees on associated biodiversity can be actively modified by promoting beneficial forest structures. Nevertheless, integrating non-native tree species, even in mixtures with native trees, will invariably alter assemblage structures of associated biota, which can compromise conservation efforts targeted at typical species composition.

Principal determinants of species and functional diversity of carabid beetle assemblages during succession at post-industrial sites

2017 ◽  
Vol 107 (4) ◽  
pp. 466-477 ◽  
Author(s):  
J. Sipos ◽  
J. Hodecek ◽  
T. Kuras ◽  
A. Dolny
Keyword(s):  
Species Richness ◽  
Functional Diversity ◽  
Restoration Ecology ◽  
Ground Beetle ◽  
Late Phase ◽  
Species Traits ◽  
Ground Beetles ◽  
Trophic Niche ◽  
Beetle Assemblages ◽  
Post Industrial

AbstractAlthough ecological succession is one of the principal focuses of recent restoration ecology research, it is still unclear which factors drive this process and positively influence species richness and functional diversity. In this study we sought to elucidate how species traits and functional diversity change during forest succession, and to identify important factors that determine the species in the observed assemblages. We analyzed species richness and functional diversity of ground beetle assemblages in relation to succession on post-industrial localities after habitat deterioration caused by spoil deposition. We selected ground beetles as they are known to be sensitive to landscape changes (with a large range of responses), and their taxonomy and ecology are generally well-known. Ground beetles were sampled on the spoil heaps during the last 30 years when spontaneous succession occurred. To calculate functional diversity, we used traits related to habitat and trophic niche, i.e. food specialization, wing morphology, trophic level, and bio-indication value. Ground beetle species were found to be distributed non-randomly in the assemblages in the late phase of succession. Ordination analyses revealed that the ground beetle assemblage was significantly associated with the proportion of forested area. Environmental heterogeneity generated assemblages that contained over-dispersed species traits. Our findings indicated that environmental conditions at late successional stages supported less mobile carnivorous species. Overall, we conclude that the decline in species richness and functional diversity in the middle of the studied succession gradient indicated that the assemblages of open habitats had been replaced by species typical of forest ecosystems.

scholarly journals Nonstationary Analysis of Annual Maximum Streamflow of Canada

2015 ◽  
Vol 28 (5) ◽  
pp. 1788-1805 ◽  
Author(s):  
Xuezhi Tan ◽  
Thian Yew Gan
Keyword(s):  
Land Use ◽  
Frequency Analysis ◽  
Anthropogenic Impacts ◽  
Probability Distributions ◽  
Temporal Trends ◽  
Annual Maximum ◽  
Monotonic Trend ◽  
Abrupt Changes ◽  
Nonstationary Frequency

Abstract Both natural climate change and anthropogenic impacts may cause nonstationarities in hydrological extremes. In this study, long-term annual maximum streamflow (AMS) records from 145 stations over Canada were used to investigate the nonstationary characteristics of AMS, which include abrupt changes and monotonic temporal trends. The nonparameteric Pettitt test was applied to detect abrupt changes, while temporal monotonic trend analysis in AMS series was conducted using the nonparameteric Mann–Kendall and Spearman tests, as well as a parametric Pearson test. Nonstationary frequency analysis of the AMS series was done using a group of nonstationary probability distributions. The nonstationary characteristics of Canadian AMS were further investigated in terms of the Hurst exponent (H), which represents the long-term persistence (LTP) of streamflow data. The results presented here indicate that for Canadian AMS data, abrupt changes are detected more frequently than monotonic trends, partly because many rivers began to be regulated in the twentieth century. Drainage basins that have experienced significant land-use changes are more likely to show temporal trends in AMS, compared to pristine basins with stable land-use conditions. The nonstationary characteristics of AMS were accounted for by fitting the data with probability distributions with time-varying parameters. Large H found in almost ⅔ of the Canadian AMS dataset indicates strong LTP, which may partly represent the presence of long-term memories in many Canadian river basins. Furthermore, H values of AMS data are positively correlated with the basin area of Canadian rivers. It seems that nonstationary frequency analysis, instead of the traditional stationary hydrologic frequency analysis, should be employed in the future.

scholarly journals Atmospheric Deposition of Phosphorus to the Everglades: Concepts, Constraints, and Published Deposition Rates for Ecosystem Management

2002 ◽  
Vol 2 ◽  
pp. 1843-1873 ◽  
Author(s):  
Garth W. Redfield
Keyword(s):  
Land Use ◽  
Atmospheric Deposition ◽  
Particle Deposition ◽  
Spatial Scales ◽  
Ecosystem Dynamics ◽  
Bulk Precipitation ◽  
Land Use Patterns ◽  
Deposition Rates ◽  
P Flux

This paper summarizes concepts underlying the atmospheric input of phosphorus (P) to ecosystems, published rates of P deposition, measurement methods, and approaches to future monitoring and research. P conveyed through the atmosphere can be a significant nutrient source for some freshwater and marine ecosystems. Particle sources and sinks at the land-air interface produce variation in P deposition from the atmosphere across temporal and spatial scales. Natural plant canopies can affect deposition rates by changing the physical environment and surface area for particle deposition. Land-use patterns can alter P deposition rates by changing particle concentrations in the atmosphere. The vast majority of P in dry atmospheric deposition is conveyed by coarse (2.5 to 10 μm) and giant (10 to 100 μm) particles, and yet these size fractions represent a challenge for long-term atmospheric monitoring in the absence of accepted methods for routine sampling. Most information on P deposition is from bulk precipitation collectors and wet/dry bucket sampling, both with questionable precision and accuracy. Most published annual rates of P deposition are gross estimates derived from bulk precipitation sampling in locations around the globe and range from about 5 to well over 100 mg P m–2year–1, although most inland ecosystems receive between 20 and 80 mg P m–2year–1. Rates below 30 mg P m–2year–1are found in remote areas and near coastlines. Intermediate rates of 30 to 50 mg P m–2year–1are associated with forests or mixed land use, and rates of 50 to 100 mg P m–2year–1or more are often recorded from urban or agricultural settings. Comparison with other methods suggests that these bulk precipitation estimates provide crude boundaries around actual P deposition rates for various land uses. However, data screening cannot remove all positive bias caused by contamination of bucket or bulk collectors. As a consequence, continued sampling with these standard collectors in a region will not reduce the large uncertainty in rates derived from existing data. Calibrated surface accumulation methods hold promise as a primary means to estimate P flux in future monitoring. New methods for long-term P deposition monitoring will require an intercomparison of P flux estimates from surrogate surfaces, impactor sampling of particle concentrations combined with deposition models, and “throughfall” estimates for natural canopies. With better sampling methods and more long-term monitoring data, the importance of atmospheric P deposition in ecosystem dynamics and management can be better understood and predicted.

37,000 Years and More in Tropical Australia: Investigating Long-Term Archaeological Trends in Cape York Peninsula

1997 ◽  
Vol 63 ◽  
pp. 1-23 ◽  
Author(s):  
Bruno David ◽  
Harry Lourandos
Keyword(s):  
Land Use ◽  
Late Holocene ◽  
Temporal Trends ◽  
Temporal Distribution ◽  
Radiocarbon Dates ◽  
Demographic Processes ◽  
Changing Patterns ◽  
Cape York ◽  
Historical Antecedents

The prehistory of Cape York Peninsula, in tropical northern Australia, has been more intensively investigated than that of most other parts of the continent. As a result, a considerable database now exists by which long-term archaeological trends can be evaluated. In this paper we investigate temporal trends in occupational intensities and patterns of land use during the last 37,000 years by employing: 1, the temporal distribution of all radiocarbon dates obtained for the region; 2, the numbers of sites occupied through time; and 3, rates of establishment of new sites during the course of prehistory. These archaeological trends are then compared with the palaeo-environmental record of the region to determine its potential influence on the trends. We conclude that an initial, long period of regional occupation occurred (c. 37,000–4000 BP) when cultural trends varied in tandem with gross environmental fluctuations. This was followed by a late Holocene period (post 4000 BP) when cultural trajectories diverged significantly from environmental trends. This suggests that more complex Aboriginal demographic processes were set in train during the late Holocene, associated with social structures that were more dynamic than previously. We suggest that while changing patterns of land use may be apparent, their understanding requires an enquiry into periods of emergence — that is, their immediate historical antecedents. These results have broader implications for our understanding of Australian prehistory and the prehistory of other hunter-gatherer societies.

Sign in / Sign up

Export Citation Format

Share Document