Multidecadal trends in area burned with high severity in the Selway-Bitterroot Wilderness Area 1880–2012

2017 ◽  
Vol 26 (11) ◽  
pp. 930 ◽  
Author(s):  
Penelope Morgan ◽  
Andrew T. Hudak ◽  
Ashley Wells ◽  
Sean A. Parks ◽  
L. Scott Baggett ◽  
...  

Multidecadal trends in areas burned with high severity shape ecological effects of fires, but most assessments are limited to ~30 years of satellite data. We analysed the proportion of area burned with high severity, the annual area burned with high severity, the probability areas burned with high severity and also the area reburned (all severities and high burn severity only) over 133 years across 346265ha within the Selway-Bitterroot Wilderness (SBW) Area in Idaho, United States. We used burn severity class inferred from digitised aerial photography (1880–2000) and satellite imagery (1973–2012). Over this long record, the proportion burned with high severity did not increase, despite extensive area burned in recent decades. Much greater area burned with high severity during the Early (1880–1934) and Late (1975–2012) periods than during the Middle period (1935–1974), paralleling trends in area burned. Little area reburned with high severity, and fires in the Early period limited the extent of fires burning decades later in the Late period. Our results suggest that long-term data across large areas provides useful context on recent trends, and that projections for the extent and severity of future fires must consider prior fires and fire management.

2020 ◽  
Vol 47 (8) ◽  
pp. 709
Author(s):  
Rachel Paltridge ◽  
Nolia Napangati Ward ◽  
John Tjupurrula West ◽  
Kate Crossing

Abstract ContextFeral cat is a favoured food item in some Australian Indigenous communities. We describe how cats are hunted and whether cat hunting can contribute to the persistence of threatened species. AimsTo determine whether cat hunting by expert trackers has the potential to be an effective method of managing predation impacts on threatened species at key sites. MethodsWe recorded all cats captured on the Kiwirrkurra Indigenous protected area (Kiwirrkurra IPA) over a 5-year period by offering incentive payments for hunters to report their catch. For a subset of hunts, we measured the duration and distance of the hunt. We compared the frequency of occurrence of cat tracks in 2-ha track plots between the hunting zone and more remote, unmanaged areas. At a finer scale, we compared cat presence at bilby burrows inside and outside the hunting zone. Key resultsIn all, 130 cats were removed from the Kiwirrkurra IPA from 2014 to 2019. Hunts took an average of 62min to complete and a team of four hunters could catch up to four cats in a single day. Although cats still occurred throughout the hunting zone, we found that cat detections at track plots were less likely in the areas where cats were hunted. Long-term data suggest that threatened species have persisted better in areas where there is an active presence of hunters. ConclusionsCat hunting by Indigenous tracking experts is an efficient method of despatching cats at localised sites. Following footprints on foot facilitates the targeting of individual cats that are hunting at threatened species burrows. More rigorous studies are required to determine whether cat hunting significantly reduces predation on threatened species, or whether there are other co-benefits of maintaining a presence of hunters in the landscape (such as fine-scale fire management) that are more important for the persistence of vulnerable prey. Implications Wherever open sandy substrates occur, there is potential to employ Indigenous expert trackers to assist with the removal of problem cats, such as, for example, to complete cat eradication inside fenced reintroduction sites, or at times of peak prey vulnerability, such as breeding events or after bushfires.


2017 ◽  
Vol 26 (4) ◽  
pp. 269 ◽  
Author(s):  
John T. Abatzoglou ◽  
Crystal A. Kolden ◽  
A. Park Williams ◽  
James A. Lutz ◽  
Alistair M. S. Smith

Interannual variability in burn severity is assessed across forested ecoregions of the western United States to understand how it is influenced by variations in area burned and climate during 1984–2014. Strong correlations (|r| > 0.6) between annual area burned and climate metrics were found across many of the studied regions. The burn severity of individual fires and fire seasons was weakly, but significantly (P < 0.05), correlated with burned area across many regions. Interannual variability in fuel dryness evaluated with fuel aridity metrics demonstrated weak-to-moderate (|r| >0.4) relationships with regional burn severity, congruent with but weaker than those between climate and area burned for most ecoregions. These results collectively suggest that irrespective of other factors, long-term increases in fuel aridity will lead to increased burn severity in western United States forests for existing vegetation regimes.


Author(s):  
Ricardo Sánchez-Murillo

This study presents a hydrogeochemical analysis of spring responses (2013-2017) in the tropical mountainous region of the Central Valley of Costa Rica. The isotopic distribution of δ18O and δ2H in rainfall resulted in a highly significant meteoric water line: δ2H = 7.93×δ18O + 10.37 (r2=0.97). Rainfall isotope composition exhibited a strong dependent seasonality. The isotopic variation (δ18O) of two springs within the Barva aquifer was simulated using the FlowPC program to determine mean transit times (MTTs). Exponential-piston and dispersion distribution functions provided the best-fit to the observed isotopic composition at Flores and Sacramento springs, respectively. MTTs corresponded to 1.23±0.03 (Sacramento) and 1.42±0.04 (Flores) years. The greater MTT was represented by a homogeneous geochemical composition at Flores, whereas the smaller MTT at Sacramento is reflected in a more variable geochemical response. The results may be used to enhance modelling efforts in central Costa Rica, whereby scarcity of long-term data limits water resources management plans.


Author(s):  
L. Vesnina ◽  
G. Lukerina ◽  
T. Ronzhina ◽  
A. Savos’kin ◽  
D. Surkov

The long-term data from morphometric studies of Artemia males from bisexual and parthenogenetic populations from hyperhaline reservoirs of the Altai region (Bolshoe Yarovoe Lake, Maloe Shklo Lake, and the Tanatar Lakes system) is analyzed in this paper. The description of signs of sexual dimorphism and sexual structure in different populations is given. The influence of brine salinity and hydrogen index on morphometric parameters of males was analyzed. There are differences in the sexual structure of the Artemia population: in the lakes Maloe Shklo and the thanatar system, the populations are bisexual (the share of males is 28.5 — 75.0 %), in the lake Bolshoe yarovoe — parthenogenetic (the share of males on average does not exceed 3 %). At the same time, sexual dimorphism is typical for both types of populations: females are larger than males, males have a larger head (the distance between the eyes is greater by 15.5 %, the diameter of the eye is 26.1 %, the length of the antenna is 22.3 %) and a larger number of bristles (36.1 %). The greatest variability is observed in the parameters of the Furka structure associated with the salinity of water by feedback and the pH — line indicator. Significant differences between the samples of males were revealed. The largest number of significant differences in morphometric indicators was found between samples of males from bisexual populations (lake thanatar and lake Maloe Shklo), the smallest — between males from the parthenogenetic population of lake Bolshoe yarovoe and males from lake Maloe Shklo.


Author(s):  
Andrea Cardillo ◽  
Andrea Zaghini
Keyword(s):  

2020 ◽  
Vol 16 ◽  
Author(s):  
Kannappan Panchamoorthy Gopinath ◽  
Malolan Rajagopal ◽  
Abhishek Krishnan ◽  
Shweta Kolathur Sreerama

Background: Depletion and contamination of environmental resources such as water, air and soil caused by human activities is an increasingly important challenge faced around the world. The consequences of environmental pollution are felt acutely by all living beings, both on a short and long-term basis, thereby making methods of remediation of environmental pollution an urgent requirement. Objectives: The objective of this review is to dissect the complications caused by environmental degradation, highlight advancements in the field of nanotechnology and to scrutinize its applications in environmental remediation. Furthermore, the review aims to concisely explain the merits and drawbacks of nanotechnology compared to existing methods. Conclusion: The current and potential applications of nanomaterials and nanocomposites in the prevention, control and reduction of air, water and soil pollution and the mechanisms involved have been elucidated, as have their various merits and demerits. The applications of nanotechnology in the fields of carbon capture and agriculture have also received attention in this review.


Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Jessie M. Dodge ◽  
Eva K. Strand ◽  
Andrew T. Hudak ◽  
Benjamin C. Bright ◽  
Darcy H. Hammond ◽  
...  

Abstract Background Fuel treatments are widely used to alter fuels in forested ecosystems to mitigate wildfire behavior and effects. However, few studies have examined long-term ecological effects of interacting fuel treatments (commercial harvests, pre-commercial thinnings, pile and burning, and prescribed fire) and wildfire. Using annually fitted Landsat satellite-derived Normalized Burn Ratio (NBR) curves and paired pre-fire treated and untreated field sites, we tested changes in the differenced NBR (dNBR) and years since treatment as predictors of biophysical attributes one and nine years after the 2007 Egley Fire Complex in Oregon, USA. We also assessed short- and long-term fuel treatment impacts on field-measured attributes one and nine years post fire. Results One-year post-fire burn severity (dNBR) was lower in treated than in untreated sites across the Egley Fire Complex. Annual NBR trends showed that treated sites nearly recovered to pre-fire values four years post fire, while untreated sites had a slower recovery rate. Time since treatment and dNBR significantly predicted tree canopy and understory green vegetation cover in 2008, suggesting that tree canopy and understory vegetation cover increased in areas that were treated recently pre fire. Live tree density was more affected by severity than by pre-fire treatment in either year, as was dead tree density one year post fire. In 2008, neither treatment nor severity affected percent cover of functional groups (shrub, graminoid, forb, invasive, and moss–lichen–fungi); however, by 2016, shrub, graminoid, forb, and invasive cover were higher in high-severity burn sites than in low-severity burn sites. Total fuel loads nine years post fire were higher in untreated, high-severity burn sites than any other sites. Tree canopy cover and density of trees, saplings, and seedlings were lower nine years post fire than one year post fire across treatments and severity, whereas live and dead tree basal area, understory surface cover, and fuel loads increased. Conclusions Pre-fire fuel treatments effectively lowered the occurrence of high-severity wildfire, likely due to successful pre-fire tree and sapling density and surface fuels reduction. This study also quantified the changes in vegetation and fuels from one to nine years post fire. We suggest that low-severity wildfire can meet prescribed fire management objectives of lowering surface fuel accumulations while not increasing overstory tree mortality.


2021 ◽  
pp. 102562
Author(s):  
Laura Ursella ◽  
Sara Pensieri ◽  
Enric Pallàs-Sanz ◽  
Sharon Z. Herzka ◽  
Roberto Bozzano ◽  
...  

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