scholarly journals Evaluation of satellite-derived burned area products for the fynbos, a Mediterranean shrubland

2012 ◽  
Vol 21 (1) ◽  
pp. 36 ◽  
Author(s):  
Helen M. de Klerk ◽  
Adam M. Wilson ◽  
Karen Steenkamp

Fire is a critical ecological process in the fynbos of the south-western area of South Africa, as it is for all dwarf Mediterranean shrublands. We evaluated the potential of current publicly available MODIS burned area products to contribute to an accurate fire history of the fynbos. To this end, we compared the Meraka Institute’s MODIS burned area product, based on the Giglio algorithm (termed the ‘WAMIS’ product) as well as the standard MODIS MCD45A1 burned area product, based on the Roy algorithm, with comprehensive manager-mapped fire boundary data. We used standard inventory accuracy assessment (number and size of individual burn scars) and confusion matrix techniques. Results showed promise for both burned area products, depending on the intended use. The MCD45A1 had low errors of commission (8.1–19.1%) and high consumer’s accuracy (80.9–91.9%), but relatively common errors of omission, making it useful for studies that need to identify burned pixels with a high degree of certainty. However, the WAMIS product generally had low errors of omission (12.2–43.8%) and greater producer’s accuracy (56.2–87.6%), making it a useful tool for supplementing manager-mapped fire records, especially for fynbos remnants occurring outside protected areas.

2017 ◽  
Vol 21 (2) ◽  
pp. 193-202 ◽  
Author(s):  
ALEXANDER BERGS ◽  
THOMAS HOFFMANN

What do we know about the past? For at least some languages, we have textual (or archaeological) evidence from various periods – beyond that, there is only reconstruction. But even when we have some textual evidence, what does it tell us? The answer to this question crucially depends on the way we approach the question: we can treat texts as decontextualized, linguistic evidence, as Neogrammarian or Structuralist studies have done (see McMahon 1994: 17–32). Such an approach already allows us to discover important generalizations about the linguistic state of affairs of a particular language or historical period. Using decontextualized historical evidence, for example, we can already ascertain with a high degree of certainty that in Old English voiced and voiceless fricatives were allophones, rather than phonemes, that there was nodo-periphrasis in Middle English, and that in Early Modern English there was some variability between third-person singular present tense {-s} and {-th} – just as we know that present-day Japanese and Korean use postpositions, rather than prepositions.


2020 ◽  
Vol 29 (10) ◽  
pp. 907 ◽  
Author(s):  
Nickolas Castro Santana ◽  
Osmar Abílio de Carvalho Júnior ◽  
Roberto Arnaldo Trancoso Gomes ◽  
Renato Fontes Guimarães

The Moderate Resolution Imaging Spectroradiometer (MODIS) products are the most used in burned-area monitoring, on regional and global scales. This research aims to evaluate the accuracy of the MODIS burned-area and active-fire products to describe fire patterns in Brazil in the period 2001–2015. The accuracy analysis, in the year 2015, compared the MODIS products (MCD45/MCD64) and the burned areas extracted by the visual interpretation of the LANDSAT/Operational Land Imager (OLI) images from the confusion matrix. The accuracy analysis of the active-fire products (MOD14/MYD14) in the year 2015 used linear regression. We used the most accurate burned-area product (MCD64), in conjunction with environmental variables of land use and climate. The MCD45 product presented a high error of commission (>36.69%) and omission (>77.04%) for the whole country. The MCD64 product had fewer errors of omission (64.05%) compared with the MCD45 product, but increased errors of commission (45.85%). MCD64 data in 2001–2015 showed three fire domains in Brazil determined by the climatic pattern. Savanna and grassy areas in semi-humid zones are the most prone areas to fire, burning an average of 25% of their total area annually, with a fire return interval of 5–6 years.


2015 ◽  
Vol 24 (1) ◽  
pp. 70 ◽  
Author(s):  
Aaron M. Sparks ◽  
Luigi Boschetti ◽  
Alistair M. S. Smith ◽  
Wade T. Tinkham ◽  
Karen O. Lannom ◽  
...  

Although fire is a common disturbance in shrub–steppe, few studies have specifically tested burned area mapping accuracy in these semiarid to arid environments. We conducted a preliminary assessment of the accuracy of the Monitoring Trends in Burn Severity (MTBS) burned area product on four shrub–steppe fires that exhibited varying degrees of within-fire patch heterogeneity. Independent burned area perimeters were derived through visual interpretation and were used to cross-compare the MTBS burned area perimeters with classifications produced using set thresholds on the Relativised differenced Normalised Burn Index (RdNBR), Mid-infrared Burn Index (MIRBI) and Char Soil Index (CSI). Overall, CSI provided the most consistent accuracies (96.3–98.6%), with only small commission errors (1.5–4.4%). MIRBI also had relatively high accuracies (92.2–97.9%) and small commission errors (2.1–10.8%). The MTBS burned area product had higher commission errors (4.3–15.5%), primarily due to inclusion of unburned islands and fingers within the fire perimeter. The RdNBR burned area maps exhibited lower accuracies (92.9–96.0%). However, the different indices when constrained by the MTBS perimeter provided variable results, with CSI providing the highest and least variable accuracies (97.4–99.1%). Studies seeking to use MTBS perimeters to analyse trends in burned area should apply spectral indices to constrain the final burned area maps. The present paper replaces a former paper of the same title (http://dx.doi.org/10.1071/WF13206), which was withdrawn owing to errors discovered in data analysis after the paper was accepted for publication.


Author(s):  
Aaron M. Sparks ◽  
Luigi Boschetti ◽  
Wade T. Tinkham ◽  
Alistair M. S. Smith ◽  
Karen O. Lannom ◽  
...  

2006 ◽  
Vol 33 (1) ◽  
pp. 145-166 ◽  
Author(s):  
Graeme W. Dean ◽  
Peter W. Wolnizer ◽  
Frank L. Clarke

A major, unique accounting archival source, the R.J. Chambers Collection comprises both hard copy and, utilizing cutting-edge search technology, internet accessible materials. From his academic beginnings, Chambers was an orderly person, an archivist of the extensive and varied evidence that underpinned his proposals for accounting reform. Opening research areas for accounting biography, the development of accounting thought, the history of accounting institutions, prosopography, public sector accounting history, and comparative international accounting history are foremost amongst the myriad justifications for seeking to unravel the accounting history “lodes” in archives such as the Goldberg, Chambers, and Briloff Collections [Potter, 2003]. The archiving of the meticulously kept Chambers papers from 1947–1999 provides an opportunity for unfolding the background to events previously withheld from accounting history scholars. Professional episodes in relation to inflation accounting, standard setting, proposals to reform accounting education, and the like that appeared prima facie to be worth investigating are now open to scrutiny from a different angle, with a different type of evidence available in this Collection. This Collection provides a high degree of archival provenance. In particular, it represents an orderly retention of past documentation of what Chambers wrote, and perhaps uniquely for accounting historians, received; thus, providing an extensive window from which to examine the disorderly present environment of acounting.


2021 ◽  
Vol 11 (2) ◽  
pp. 216-218
Author(s):  
Marta Brandão Calçada ◽  
Luís Fernandes ◽  
Rita Soares Costa ◽  
Sara Montezinho ◽  
Filipa Martins Duarte ◽  
...  

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are the most recently approved drug class for the treatment of type 2 diabetes mellitus (T2D). Although they are largely well-tolerated, their intake has been associated with euglycemic diabetic ketoacidosis (DKA) in some rare cases. We report the case of a 70-year-old male with type 2 diabetes and no history of DKA, who started therapy with empagliflozin one day before presenting with acute pancreatitis and laboratory findings consistent with euglycemic DKA. SGLT2i can induce euglycemic DKA from the first dose. Given the atypical presentation, a high degree of clinical suspicion is required to recognize this complication.


2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
O Oyende ◽  
J Jackman

Abstract Introduction Streptococcal myositis is a rare form of infectious myositis caused by Lansfield A beta-haemolytic streptococci. It is characterised by rapidly spreading inflammation that can result in severe systemic toxicity and necrosis of the affected tissue if not diagnosed and aggressively treated. Presentation We report a case of a 42-year-old male who presented with a one-week history of worsening right axillary swelling that progressed to painful swelling of his arm. Inflammatory markers were significantly elevated with a white cell count of 17 ×109/L and C-reactive protein of 212 mg/L. On examination, a fluctuant axillary swelling was appreciated, and a decision was made for incision and drainage under general anaesthetic. Intraoperative aspiration of his arm revealed copious purulent fluid prompting intraoperative orthopaedic consult and exploration of the anterior compartment in which there was extensive involvement of the biceps muscle. The microbiological analysis revealed gram-positive cocci in chains, and microbiology advice sought for tailoring of antibiotic regimen. He has recovered well. Discussion Though uncommon, the emergency general surgeon should have a high degree of suspicion when evaluating soft tissue infections to avert potentially disastrous outcomes. Conclusion Early diagnosis, aggressive management with high-dose intravenous antibiotics, and surgical debridement are principles to treat this rare, life-threatening infection.


Fire ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 26
Author(s):  
Casey Teske ◽  
Melanie K. Vanderhoof ◽  
Todd J. Hawbaker ◽  
Joe Noble ◽  
John Kevin Hiers

Development of comprehensive spatially explicit fire occurrence data remains one of the most critical needs for fire managers globally, and especially for conservation across the southeastern United States. Not only are many endangered species and ecosystems in that region reliant on frequent fire, but fire risk analysis, prescribed fire planning, and fire behavior modeling are sensitive to fire history due to the long growing season and high vegetation productivity. Spatial data that map burned areas over time provide critical information for evaluating management successes. However, existing fire data have undocumented shortcomings that limit their use when detailing the effectiveness of fire management at state and regional scales. Here, we assessed information in existing fire datasets for Florida and the Landsat Burned Area products based on input from the fire management community. We considered the potential of different datasets to track the spatial extents of fires and derive fire history metrics (e.g., time since last burn, fire frequency, and seasonality). We found that burned areas generated by applying a 90% threshold to the Landsat burn probability product matched patterns recorded and observed by fire managers at three pilot areas. We then created fire history metrics for the entire state from the modified Landsat Burned Area product. Finally, to show their potential application for conservation management, we compared fire history metrics across ownerships for natural pinelands, where prescribed fire is frequently applied. Implications of this effort include increased awareness around conservation and fire management planning efforts and an extension of derivative products regionally or globally.


Author(s):  
Eric Helleiner

Abstract As the global crisis triggered by the COVID-19 virus unfolded, The Economist magazine published a cover in May 2020 titled “Goodbye globalization: the dangerous lure of self-sufficiency.” The title summed up well the new political interest in the ideology of national economic self-sufficiency in the pandemic context. Unfortunately, contemporary textbooks in the field of international political economy (IPE) say little about this kind of “autarkic” thought. No survey of the history of autarkic thought exists even within specialist IPE literature or in the fields of intellectual history and the history of economic thought. Filling this gap in existing scholarship, this article highlights a rich history of autarkic thought that includes the ideas of famous thinkers such as Jean-Jacques Rousseau, Johann Fichte, Mohandas Gandhi, and John Maynard Keynes. Three core rationales for a high degree of national self-sufficiency have been advanced in the past: (1) insulation from foreign economic influence, (2) insulation from foreign political and/or cultural influence, and (3) the promotion of international peace. At the same time, considerable disagreements have existed among autarkists about some of these rationales and their relative importance, as well as about the precise meaning of national self-sufficiency. These disagreements stemmed not just from differences in their specific goals but also from the different conditions across time and space in which autarkic thought was developed. In addition to improving understanding of the autarkic ideological tradition, this article contributes to emerging scholarship attempting to overcome Western-centrism in IPE scholarship as well as literature exploring the new politics of de-globalization in the current era.


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