Persistent spatial gaps in ornithological study in Australia, 1901–2011

2020 ◽  
Vol 47 (2) ◽  
pp. 264-271
Author(s):  
Michael A. Weston ◽  
Maree R. Yarwood ◽  
Desley A. Whisson ◽  
Matthew R. E. Symonds
Keyword(s):  
Spatial Patterns ◽  
Review Paper ◽  
Gap Analysis ◽  
Research Effort ◽  
Ecological Research ◽  
Continental Scale ◽  
Australian Birds ◽  
Biogeographical Regions ◽  
Explicit Study

At the continental scale, ecological research effort is not spatially uniform. We used a century-long bibliometric database of the journal Emu – Austral Ornithology to index the spatial patterns in bird research in Australia (from articles with explicit study locations). Studies have been concentrated in Tasmania and the southwest, southeast and coastal parts of the mainland. Large spatial gaps exist in ornithological study, which are similar to those identified by Arnold Robert McGill in his 1948 review paper ( McGill 1948 ). Pre-1948 only 9.4% of articles [n = 2,107] fell within the gaps mapped by McGill in 1948, indicating that his mapping was largely accurate. These gaps have largely persisted; only 11.2% of the 1,498 articles published since 1948 came from within those gaps. We present a complementary spatial gap analysis, which focuses on studies of areas with broadly similar biogeographies (Interim Biogeographical Regions of Australia (IBRAs)). Of 85 mainland IBRAs (of 89 defined), five have no bird studies from within them (368,380 km2; 4.9% of Australia), and 34 have less than 10 studies (3,335,498 km2; 43.9%). We intersect IBRAs with McGill's gaps and show that some IBRAs within McGill's gaps are now better-studied, but 64.8% of the area within the McGill gaps boundaries comprises IBRAs where there have been no post-1948 studies in Emu. We also present an updated map of key geographical gaps in the study of Australian birds, which apparently remain extensive 60 years after they were first identified.

Biological determinants of research effort on Australian birds: a comparative analysis

2018 ◽  
Vol 119 (1) ◽  
pp. 38-44 ◽  
Author(s):  
Maree R. Yarwood ◽  
Michael A. Weston ◽  
Matthew R. E. Symonds
Keyword(s):  
Comparative Analysis ◽  
Research Effort ◽  
Australian Birds ◽  
Biological Determinants

scholarly journals Gradients of column CO<sub>2</sub> across North America from the NOAA Global Greenhouse Gas Reference Network

2017 ◽  
Vol 17 (24) ◽  
pp. 15151-15165 ◽  
Author(s):  
Xin Lan ◽  
Pieter Tans ◽  
Colm Sweeney ◽  
Arlyn Andrews ◽  
Andrew Jacobson ◽  
...  
Keyword(s):  
North America ◽  
Greenhouse Gas ◽  
Spatial Patterns ◽  
Reference Network ◽  
Spatial Gradients ◽  
Continental Scale ◽  
Satellite Retrievals ◽  
The Impact ◽  
Total Column

Abstract. This study analyzes seasonal and spatial patterns of column carbon dioxide (CO2) over North America, calculated from aircraft and tall tower measurements from the NOAA Global Greenhouse Gas Reference Network from 2004 to 2014. Consistent with expectations, gradients between the eight regions studied are larger below 2 km than above 5 km. The 11-year mean CO2 dry mole fraction (XCO2) in the column below  ∼  330 hPa ( ∼  8 km above sea level) from NOAA's CO2 data assimilation model, CarbonTracker (CT2015), demonstrates good agreement with those calculated from calibrated measurements on aircraft and towers. Total column XCO2 was attained by combining modeled CO2 above 330 hPa from CT2015 with the measurements. We find large spatial gradients of total column XCO2 from June to August, with north and northeast regions having  ∼  3 ppm stronger summer drawdown (peak-to-valley amplitude in seasonal cycle) than the south and southwest regions. The long-term averaged spatial gradients of total column XCO2 across North America show a smooth pattern that mainly reflects the large-scale circulation. We have conducted a CarbonTracker experiment to investigate the impact of Eurasian long-range transport. The result suggests that the large summertime Eurasian boreal flux contributes about half of the north–south column XCO2 gradient across North America. Our results confirm that continental-scale total column XCO2 gradients simulated by CarbonTracker are realistic and can be used to evaluate the credibility of some spatial patterns from satellite retrievals, such as the long-term average of growing-season spatial patterns from satellite retrievals reported for Europe which show a larger spatial difference ( ∼  6 ppm) and scattered hot spots.

A sub-continental scale living laboratory: Spatial patterns of savanna vegetation over a rainfall gradient in northern Australia

2011 ◽  
Vol 151 (11) ◽  
pp. 1417-1428 ◽  
Author(s):  
Lindsay B. Hutley ◽  
Jason Beringer ◽  
Peter R. Isaac ◽  
Jorg M. Hacker ◽  
Lucas A. Cernusak
Keyword(s):  
Spatial Patterns ◽  
Northern Australia ◽  
Rainfall Gradient ◽  
Continental Scale ◽  
Savanna Vegetation

scholarly journals Understanding Hydrologic Variability across Europe through Catchment Classification

2016 ◽  
Author(s):  
Anna Kuentz ◽  
Berit Arheimer ◽  
Yeshewatesfa Hundecha ◽  
Thorsten Wagener
Keyword(s):  
Spatial Patterns ◽  
Geographical Location ◽  
Dynamic Modelling ◽  
Regression Tree ◽  
Classification And Regression Tree ◽  
Low Flow ◽  
Average Percentage ◽  
Continental Scale ◽  
Hydrologic Variability ◽  
Predictions In Ungauged Basins

Abstract. This study contributes to better understanding the physical controls on spatial patterns of pan-European flow signatures – taking advantage of large open datasets for catchment classification and comparative hydrology. We explored similarities in 16 flow signatures and 35 catchment descriptors across entire Europe. A database of catchment descriptors and selected flow signatures was compiled for 35 215 catchments and 1366 river gauges across Europe. Correlation analyses and stepwise regressions were used to identify the best explanatory variables for each signature resulting in a total of 480 regression models to predict signatures for similar catchments. Catchments were clustered and analyzed for similarities in flow signature values, physiography and for the combination of the two. From the statistical analysis, we found: (i) about 400 statistically significant correlations between flow signatures and physiography; (ii) a 15 to 33 % (depending on the classification used) improvement in regression model skills using catchment classification vs. the full domain; and (iii) 12 out of 16 flow signatures to be mainly controlled by climatic characteristics, while topography was the main control for flashiness of flow and low flow magnitude, and geology for the flashiness of flow. Classifying catchments based on flow signatures or on physiographic characteristics led to very different spatial patterns, but a classification and regression tree (CART) allowed us to predict flow signatures-based classes according to catchment physiographic characteristics with an average percentage of 60 % of correctly classified catchments in each class. As a result, we show that Europe can be divided into ten classes with both similar flow signatures and physiography. We noted the importance of separating energy-limited catchments from moisture-limited catchment to understand catchment behavior. For improved understanding, we interpreted characteristics in hydrographs, flow signatures, physiography and geographical location to define dominant flow-generating processes. We found that rainfall response, snow-melt, evapotranspiration, damping, storage capacity, and human alterations could explain the hydrologic variability across Europe. Finally, we discuss the relevance of these empirical results for predictions in ungauged basins across Europe and for dynamic modelling at the continental scale.

scholarly journals North American CO<sub>2</sub> exchange: inter-comparison of modeled estimates with results from a fine-scale atmospheric inversion

2012 ◽  
Vol 9 (1) ◽  
pp. 457-475 ◽  
Author(s):  
S. M. Gourdji ◽  
K. L. Mueller ◽  
V. Yadav ◽  
D. N. Huntzinger ◽  
A. E. Andrews ◽  
...  
Keyword(s):  
Spatial Patterns ◽  
North American ◽  
Co2 Fluxes ◽  
Fine Scale ◽  
Bottom Up ◽  
Near Surface ◽  
Continental Scale ◽  
The North ◽  
Atmospheric Observations ◽  
Atmospheric Inversion

Abstract. Atmospheric inversion models have the potential to quantify CO2 fluxes at regional, sub-continental scales by taking advantage of near-surface CO2 mixing ratio observations collected in areas with high flux variability. This study presents results from a series of regional geostatistical inverse models (GIM) over North America for 2004, and uses them as the basis for an inter-comparison to other inversion studies and estimates from biospheric models collected through the North American Carbon Program Regional and Continental Interim Synthesis. Because the GIM approach does not require explicit prior flux estimates and resolves fluxes at fine spatiotemporal scales (i.e. 1° × 1°, 3-hourly in this study), it avoids temporal and spatial aggregation errors and allows for the recovery of realistic spatial patterns from the atmospheric data relative to previous inversion studies. Results from a GIM inversion using only available atmospheric observations and a fine-scale fossil fuel inventory were used to confirm the quality of the inventory and inversion setup. An inversion additionally including auxiliary variables from the North American Regional Reanalysis found inferred relationships with flux consistent with physiological understanding of the biospheric carbon cycle. Comparison of GIM results with bottom-up biospheric models showed stronger agreement during the growing relative to the dormant season, in part because most of the biospheric models do not fully represent agricultural land-management practices and the fate of both residual biomass and harvested products. Comparison to earlier inversion studies pointed to aggregation errors as a likely source of bias in previous sub-continental scale flux estimates, particularly for inversions that adjust fluxes at the coarsest scales and use atmospheric observations averaged over long periods. Finally, whereas the continental CO2 boundary conditions used in the GIM inversions have a minor impact on spatial patterns, they have a substantial impact on the continental carbon budget, with a difference of 0.8 PgC yr−1 in the total continental flux resulting from the use of two plausible sets of boundary CO2 mixing ratios. Overall, this inter-comparison study helps to assess the state of the science in estimating regional-scale CO2 fluxes, while pointing towards the path forward for improvements in future top-down and bottom-up modeling efforts.

Characteristics of tree hollows used by Australian birds and bats

2009 ◽  
Vol 36 (5) ◽  
pp. 394 ◽  
Author(s):  
Ross L. Goldingay
Keyword(s):  
Research Effort ◽  
Bird Species ◽  
Future Research ◽  
Tree Hollows ◽  
Dead Trees ◽  
Australian Birds ◽  
Absolute Requirement ◽  
Passive Rewarming ◽  
The Many

Many hundreds of species of wildlife worldwide are dependent on tree hollows (cavities) for their survival. I reviewed the published literature for hollow-using Australian birds and microbats to document their tree-hollow requirements and to guide future research and management. Such information is vital to the conservation of these species. The hollow requirements of only 35 of 114 hollow-using bird species and 15 of 42 hollow-using microbat species were documented in some detail. This overall paucity of information limits the ability to manage for the future requirements of species. However, some generalisations can guide management until further studies are conducted. Most species used a variety of available tree species, and the extensive use of dead trees probably reflects the high likelihood of these trees containing hollows. Birds (other than large parrots) and bats chose hollow entrances of a size close to body width. Large parrots require large hollows, with a preference for large vertical spouts and trunk hollows. Few birds or bats demonstrated an absolute requirement for high (>10 m) tree hollows, with most (70%) using some hollows with entrances ≤5 m above ground. Temperature has been postulated to influence roost selection among microbats because it enables passive rewarming from torpor and there is some evidence from Australian bats to support this. Many studies suggest a future shortage of hollow-bearing trees. Currently, artificial hollows appear to be the most likely interim solution to address this. Knowledge of the natural hollow requirements of species can be used to refine artificial-hollow designs. An increase in research effort is needed to address the many gaps in knowledge that currently exist. Priorities for research include (1) many additional studies to document the characteristics of the hollow-bearing trees used by species of microbat, (2) the need to conduct long-term bioregional studies of hollow-bearing tree attrition to help identify where management responses are most needed and (3) investigating whether fire plays a significant role in the creation of tree hollows of a range of size classes and therefore may have a management use. Such information has broad relevance because it will provide ecological insight that can be applied to the management of hollow-using birds and bats elsewhere in the world.

scholarly journals Characteristics and process controls of statistical flood moments in Europe – a data based analysis

2020 ◽  
Author(s):  
David Lun ◽  
Alberto Viglione ◽  
Miriam Bertola ◽  
Jürgen Komma ◽  
Juraj Parajka ◽  
...  
Keyword(s):  
Linear Regression ◽  
Multiple Linear Regression ◽  
Eastern Europe ◽  
Spatial Patterns ◽  
Catchment Area ◽  
East European Plain ◽  
Relevant Variable ◽  
Continental Scale ◽  
The Mediterranean ◽  
Process Controls

Abstract. This paper analyses the spatial patterns and process controls of the mean annual flood (MAF), coefficient of variation (CV) and skewness (CS) of flood discharges in Europe. The data consist of maximum annual flood discharge series observed in 2370 catchments in Europe covering the period 1960–2010. On average, in Europe, the estimated moments MAF, CV and CS are 0.17 m3 s−1 km−2, 0.52 and 1.28, respectively. The results indicate that MAF is largest along the Atlantic coast, the high rainfall areas of the Mediterranean coast and in the mountain ranges of Europe, while it is smallest in the sheltered parts of the East European plain. CV is largest in Southern and Eastern Europe, while it is smallest in the regions of strong Atlantic influence. The pattern of CS is similar to that of CV, albeit a little more erratic. In the Mediterranean, MAF, CV and CS decrease strongly with catchment area suggesting that floods in small catchments are relatively very large, while in Eastern Europe the dependence is much weaker. The Process controls on the flood moments in five hydroclimatic regions are identified by correlation and multiple linear regression analyses with a range of covariates. Precipitation-related variables are found to be the main controls of the spatial patterns of MAF in most of Europe except for the regions with snow influence where air temperature is more important. Catchment area is another relevant variable. Aridity is by far the most important control of the spatial pattern of CV in all of Europe. Precipitation-related variables are relevant in Southern Europe. Overall, the findings suggest that, at the continental scale, climate variables dominate over land surface characteristics, such as land use and soil type, in controlling the spatial patterns of flood moments. Finally, the estimation accuracy of the multiple linear regression model for estimating flood moments in ungauged basins is evaluated as a baseline for more accurate local studies.

scholarly journals A grid-based map for the Biogeographical Regions of Europe

2020 ◽  
Vol 8 ◽  
Author(s):  
Marco Cervellini ◽  
Piero Zannini ◽  
Michele Di Musciano ◽  
Simone Fattorini ◽  
Borja Jiménez-Alfaro ◽  
...  
Keyword(s):  
Nature Conservation ◽  
Conservation Management ◽  
Habitats Directive ◽  
Ecological Research ◽  
European Environment Agency ◽  
Scientific Debate ◽  
Biogeographical Regions ◽  
Environment Agency ◽  
Operational Tool ◽  
Grid Based

Biogeographical units are widely adopted in ecological research and nature conservation management, even though biogeographical regionalisation is still under scientific debate. The European Environment Agency provided an official map of the European Biogeographical Regions (EBRs), which contains the official boundaries used in the Habitats and Birds Directives. However, these boundaries bisect cells in the official EU 10 km × 10 km grid used for many purposes, including reporting species and habitat data, meaning that 6881 cells overlap two or more regions. Therefore, superimposing the EBRs vector map over the grid creates ambiguities in associating some cells with European Biogeographical Regions. To provide an operational tool to unambiguously define the boundaries of the eleven European Biogeographical Regions, we provide a specifically developed raster map of Grid-Based European Biogeographical Regions (GB-EBRs). In this new map, the borders of the EBRs are reshaped to coherently match the standard European 10 km × 10 km grid imposed for reporting tasks by Article 17 of the Habitats Directive and used for many other datasets. We assign each cell to the EBR with the largest area within the cell.

scholarly journals Beta diversity and knowledge gaps of Colombia’s dry forests: implications for their conservation

Caldasia ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 1-11
Author(s):  
Gustavo H. Kattan ◽  
Camilo E. Sánchez ◽  
Catalina Vélez ◽  
Laura Ramírez ◽  
Marcela Celis
Keyword(s):  
Seed Dispersal ◽  
Beta Diversity ◽  
Secondary Succession ◽  
Research Effort ◽  
Dry Forest ◽  
Caribbean Region ◽  
Dry Forests ◽  
Ecological Processes ◽  
Frugivorous Birds ◽  
Continental Scale

On a continental scale, Neotropical dry forests exhibit high plant beta diversity, forming twelve unique floristic provinces. Conserving this diversity requires plans to protect areas in each province, based on an understanding of their particular ecological conditions. In Colombia dry forest occurs in seven regions. We explored some challenges for conserving beta diversity at the country scale by downscaling the analysis and framing it in the context of the general knowledge status of the country’s dry forests, and particularly of seed dispersal. Our literature review revealed 178 studies, with an increase in publication rate in recent years. The Cauca Valley and the Caribbean region had the most publications. More than half of studies were species inventories of plants, birds, and bats, whereas only ten studies dealt with plant-animal interactions and five with secondary succession. Analyses on plants, birds, and bats revealed high levels of dissimilarity among regions. One-half of plant species in Colombia´s dry forests are dispersed by birds and mammals. Large-sized frugivorous birds and mammals are absent from remaining forest patches, which may negatively affect patterns of seed dispersal and secondary succession. Understanding the ecological and biogeographic factors at several scales, supported by local knowledge of the ecological processes that contribute to forest integrity, is key for the conservation of the unique and distinctive species composition of regional assemblages. A coordinated research effort that integrates knowledge of ecological processes at local to national scales is a priority.

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