scholarly journals High resilience of the mycorrhizal community to prescribed seasonal burnings in a Mediterranean woodland

2020 ◽  
Author(s):  
Stav Livne-Luzon ◽  
Hagai Shemesh ◽  
Yagil Osem ◽  
Yohay Carmel ◽  
Hen Migael ◽  
...  
Keyword(s):  
Community Composition ◽  
Fungal Community ◽  
Large Scale ◽  
Conflicts Of Interest ◽  
Fire Severity ◽  
Fire Effects ◽  
The United States ◽  
Fire Season ◽  
Mediterranean Woodland ◽  
Seasonal Fires

AbstractFire effects on ecosystems range from destruction of aboveground vegetation to direct and indirect effects on belowground microorganisms. Although variation in such effects is expected to be related to fire severity, another potentially important and poorly understood factor is the effects of fire seasonality on soil microorganisms. We carried out a large-scale field experiment examining the effects of spring versus autumn burns on the community composition of soil fungi in a typical Mediterranean woodland. Although the intensity and severity of our prescribed burns were largely consistent between the two burning seasons, we detected differential fire season effects on the composition of the soil fungal community, driven by changes in the saprotrophic fungal guild. The community composition of ectomycorrhizal fungi, assayed both in pine seedling bioassays and from soil sequencing, appeared to be resilient to the variation inflicted by seasonal fires. Since changes in the soil saprotrophic fungal community can directly influence carbon emission and decomposition rates, we suggest that regardless of their intensity and severity, seasonal fires may cause changes in ecosystem functioning.DeclarationsFundingThis research was co-supported by the United States-Israel Binational Science Foundation (BSF Grant 2012081) and Tel-Hai College.Conflicts of interest/Competing interestsWe declare no conflicts of interest and that this material has not been submitted for publication elsewhere.Ethics approvalNot applicableConsent to participateNot applicableConsent for publicationNot applicableAvailability of data and materialSequences were submitted to the National Center for Biotechnology Information Sequence Read Archive under accession numbers SRRXXX◻SRRXXX.Code availabilityNot applicableAuthors’ contributionsOO HS TB YO YC conceived and designed the experiment. SSL YA HM AT performed the experiment. SIG provided the pipeline scripts, and guidance in bioinformatics work and analyses. SLL OO HS wrote the paper and analyzed the data, and all authors contributed substantially to revisions.

scholarly journals Predicting wildfire impacts on the prehistoric archaeological record of the Jemez Mountains, New Mexico, USA

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Megan M. Friggens ◽  
Rachel A. Loehman ◽  
Connie I. Constan ◽  
Rebekah R. Kneifel
Keyword(s):  
New Mexico ◽  
Fire Severity ◽  
Fire Effects ◽  
Burn Severity ◽  
Fire Season ◽  
Archaeological Sites ◽  
Archaeological Record ◽  
Human Environment ◽  
Jemez Mountains ◽  
Archaeological Materials

Abstract Background Wildfires of uncharacteristic severity, a consequence of climate changes and accumulated fuels, can cause amplified or novel impacts to archaeological resources. The archaeological record includes physical features associated with human activity; these exist within ecological landscapes and provide a unique long-term perspective on human–environment interactions. The potential for fire-caused damage to archaeological materials is of major concern because these resources are irreplaceable and non-renewable, have social or religious significance for living peoples, and are protected by an extensive body of legislation. Although previous studies have modeled ecological burn severity as a function of environmental setting and climate, the fidelity of these variables as predictors of archaeological fire effects has not been evaluated. This study, focused on prehistoric archaeological sites in a fire-prone and archaeologically rich landscape in the Jemez Mountains of New Mexico, USA, identified the environmental and climate variables that best predict observed fire severity and fire effects to archaeological features and artifacts. Results Machine learning models (Random Forest) indicate that topography and variables related to pre-fire weather and fuel condition are important predictors of fire effects and severity at archaeological sites. Fire effects were more likely to be present when fire-season weather was warmer and drier than average and within sites located in sloped, treed settings. Topographic predictors were highly important for distinguishing unburned, moderate, and high site burn severity as classified in post-fire archaeological assessments. High-severity impacts were more likely at archaeological sites with southern orientation or on warmer, steeper, slopes with less accumulated surface moisture, likely associated with lower fuel moistures and high potential for spreading fire. Conclusions Models for predicting where and when fires may negatively affect the archaeological record can be used to prioritize fuel treatments, inform fire management plans, and guide post-fire rehabilitation efforts, thus aiding in cultural resource preservation.

scholarly journals Spatial Heterogeneity of Burn Severity and First-Year Vegetation Responses Following Fire on Subalpine Plateaus in Yellowstone National Park

1989 ◽  
Vol 13 ◽  
pp. 217-224
Author(s):  
Monica Turner ◽  
Robert Gardner ◽  
William Romme
Keyword(s):  
Yellowstone National Park ◽  
National Park ◽  
Large Scale ◽  
Tree Mortality ◽  
Vegetation Type ◽  
Fire Severity ◽  
Fire Effects ◽  
Time Of Day ◽  
Burn Severity ◽  
Natural Fire

The 1988 fires that burned in Yellowstone National Park presented ecologists with a unique opportunity to investigate ecological responses to large-scale fires (Christensen et al. 1989, Knight and Wallace 1989). The Yellowstone fires created an extremely heterogeneous landscape in terms of both the overall burning patterns and the variable fire severity within burned areas. Large fires rarely consume the entire forest because of the influence of wind variations, topography, vegetation type, natural fire breaks, and the time of day that the fire passed through (Rowe and Scotter 1973, Wright and Heinselman 1973, Van Wagner 1983). Direct fire effects such as tree mortality and organic matter consumption are related to locally variable parameters such as moisture content (Brown et al. 1985, Peterson and Ryan 1986, Ryan et al. 1988), and fire severity and return intervals are often strongly influenced by topographic and edaphic variability (Habeck and Mutch 1973, Romme and Knight 1981, Hemstrom and Franklin 1982, Whitney 1986). Therefore, burned landscapes generally contain areas of low as well as high intensity fire, usually in a complex mosaic (Van Wagner 1983). These variable fire intensities result in a heterogeneous pattern of burn severities (effects of fire on the ecosystem), as well as islands of unburned vegetation. The influence of burn severity on plant reestablishment following fire is well documented (e.g., Lyon and Stickney 1976, Rowe and Scotter 1973, Viereck 1983, Ryan and Noste 1985), and the importance of the effects of limited burns and low-intensity fires on the vegetation mosaic has been recognized (Habeck and Mutch 1973, Rowe 1983). However, few studies have dealt explicitly with the spatial variation of fire effects in a systematic and quantitative way.

scholarly journals Giving Ecological Meaning to Satellite-Derived Fire Severity Metrics across North American Forests

2019 ◽  
Vol 11 (14) ◽  
pp. 1735 ◽  
Author(s):  
Parks ◽  
Holsinger ◽  
Koontz ◽  
Collins ◽  
Whitman ◽  
...  
Keyword(s):  
Spatial Variability ◽  
Fire Severity ◽  
Model Performance ◽  
Fire Effects ◽  
The United States ◽  
Google Earth ◽  
Spectral Indices ◽  
Explanatory Variables ◽  
Direct Mapping ◽  
Ground Fire

Satellite-derived spectral indices such as the relativized burn ratio (RBR) allow fire severity maps to be produced in a relatively straightforward manner across multiple fires and broad spatial extents. These indices often have strong relationships with field-based measurements of fire severity, thereby justifying their widespread use in management and science. However, satellite-derived spectral indices have been criticized because their non-standardized units render them difficult to interpret relative to on-the-ground fire effects. In this study, we built a Random Forest model describing a field-based measure of fire severity, the composite burn index (CBI), as a function of multiple spectral indices, a variable representing spatial variability in climate, and latitude. CBI data primarily representing forested vegetation from 263 fires (8075 plots) across the United States and Canada were used to build the model. Overall, the model performed well, with a cross-validated R2 of 0.72, though there was spatial variability in model performance. The model we produced allows for the direct mapping of CBI, which is more interpretable compared to spectral indices. Moreover, because the model and all spectral explanatory variables were produced in Google Earth Engine, predicting and mapping of CBI can realistically be undertaken on hundreds to thousands of fires. We provide all necessary code to execute the model and produce maps of CBI in Earth Engine. This study and its products will be extremely useful to managers and scientists in North America who wish to map fire effects over large landscapes or regions.

scholarly journals Rapidly mapping fire effects on biodiversity at a large-scale using citizen science

2020 ◽  
Author(s):  
Casey Kirchhoff ◽  
Corey Thomas Callaghan ◽  
David A. Keith ◽  
Dony Indiarto ◽  
Guy Taseski ◽  
...  
Keyword(s):  
Citizen Science ◽  
Large Scale ◽  
Fire Severity ◽  
Fire Effects ◽  
Management Actions ◽  
Disturbed Areas ◽  
Eastern Australia ◽  
Large Scale Disturbance ◽  
Wide Range ◽  
Citizen Science Project

The unprecedented scale of the 2019-2020 eastern Australian bushfires exemplifies the challenges that scientists and conservation biologists face monitoring the effects of biodiversity in the aftermath of large-scale environmental disturbances. After a large-scale disturbance there are conservation policy and management actions that need to be both timely and informed by data. By working with the public, often widely spread out over such disturbed areas, citizen science offers a unique opportunity to collect data on biodiversity responses at the appropriate scale. We detail a citizen science project, hosted through iNaturalist, launched shortly after the 2019-2020 bushfire season in eastern Australia. It rapidly (1) provided accurate data on fire severity, relevant to future recovery; and (2) delivered data on a wide range (mosses to mammals) of biodiversity responses at a scale that matched the geographic extent of these fires.

scholarly journals Wildfire severity reduces richness and alters composition of soil fungal communities in boreal forests of western Canada

2021 ◽  
Author(s):  
Nicola Day ◽  
KE Dunfield ◽  
JF Johnstone ◽  
MC Mack ◽  
MR Turetsky ◽  
...  
Keyword(s):  
Community Structure ◽  
Community Composition ◽  
Fungal Community ◽  
Boreal Forests ◽  
Fire Severity ◽  
Fungal Communities ◽  
Organic Layer ◽  
Fungal Community Structure ◽  
Soil Organic Layer ◽  
Total Fungi

© 2019 John Wiley & Sons Ltd Wildfire is the dominant disturbance in boreal forests and fire activity is increasing in these regions. Soil fungal communities are important for plant growth and nutrient cycling postfire but there is little understanding of how fires impact fungal communities across landscapes, fire severity gradients, and stand types in boreal forests. Understanding relationships between fungal community composition, particularly mycorrhizas, and understory plant composition is therefore important in predicting how future fire regimes may affect vegetation. We used an extreme wildfire event in boreal forests of Canada's Northwest Territories to test drivers of fungal communities and assess relationships with plant communities. We sampled soils from 39 plots 1 year after fire and 8 unburned plots. High-throughput sequencing (MiSeq, ITS) revealed 2,034 fungal operational taxonomic units. We found soil pH and fire severity (proportion soil organic layer combusted), and interactions between these drivers were important for fungal community structure (composition, richness, diversity, functional groups). Where fire severity was low, samples with low pH had higher total fungal, mycorrhizal, and saprotroph richness compared to where severity was high. Increased fire severity caused declines in richness of total fungi, mycorrhizas, and saprotrophs, and declines in diversity of total fungi and mycorrhizas. The importance of stand age (a surrogate for fire return interval) for fungal composition suggests we could detect long-term successional patterns even after fire. Mycorrhizal and plant community composition, richness, and diversity were weakly but significantly correlated. These weak relationships and the distribution of fungi across plots suggest that the underlying driver of fungal community structure is pH, which is modified by fire severity. This study shows the importance of edaphic factors in determining fungal community structure at large scales, but suggests these patterns are mediated by interactions between fire and forest stand composition.

How Rare Is Rare? Carrier Frequencies for Fanconi Anemia In the United States and Israel

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2229-2229
Author(s):  
Philip S Rosenberg ◽  
Hannah Tamary ◽  
Blanche P. Alter
Keyword(s):  
United States ◽  
Fanconi Anemia ◽  
Carrier Frequency ◽  
Large Scale ◽  
Conflicts Of Interest ◽  
Demographic Data ◽  
New York State ◽  
The United States ◽  
Ashkenazi Jews ◽  
The Us

Abstract Abstract 2229 Background: Although carrier frequencies for Fanconi anemia (FA) have been estimated for several founder populations, carrier frequencies in different countries remain unclear. One exception is Israel. In Jewish populations, founder mutations have been identified, e.g. the FANCC IVS+4 A>T mutation in Ashkenazi Jews, and the FANCA 2172–2173insG mutation in Moroccan Jews. The ability to test for specific mutations has enabled screening studies: the carrier frequency in Israeli Ashkenazi Jews is around 1:85; limited available data suggest that carrier frequencies in other Israeli Jewish subgroups may be similar (Tamary et al. BJH 2000). FA also occurs in Israeli Arab populations but carrier frequencies have not been determined. In contrast, there are much less data for the United States (US). Swift (Nature 1971) estimated the US FA carrier frequency as 1:300, but this estimate was based on surprisingly limited data - in total, the 12 persons with FA born in New York State from 1956 until 1967 who were known to the author among the corresponding total of 4.2 million live births. Nonetheless, this figure remains widely cited and has not been updated even after 40 years. We sought to update this estimate given the biological importance of the FA pathway. Methods: We applied Swift's approach (knowledge of the number of FA cases born during a given period with a known overall birth rate) to contemporary data for the United States and Israel. Specifically, we used the Hardy-Weinberg Law and demographic data from the Fanconi Anemia Research Fund (FARF, 488 FA) and the Israeli Fanconi Anemia Registry (ISFAR, 66 FA). Results: On average during the 1990s, 15 persons with FA were born each year in the US who eventually became known to the FARF, amongst the 4.0 million persons born each year in the US during that period. The corresponding Hardy-Weinberg carrier frequency is 1:257 (95% Confidence Interval: 1:240 – 1:277). This range describes a lower bound because ascertainment in FARF must be less than 100%. Even so, the lower confidence limit is significantly greater that 1:300. The true ascertainment in FARF is unknown. We propose that values between 40% – 60% are plausible. Using this range to adjust the observed birth incidence upwards, we obtained a plausible range for the carrier frequency of 1:156 – 1:209 [midpoint 1:182]. We applied the same approach to the ISFAR where 2.6 births per year were observed. We assumed 50% – 100% ascertainment by ISFAR since cases were identified through a country-wide hospital network. For the entire country of Israel (Jews and non-Jews combined), we obtained a plausible range for the carrier frequency of 1:66 – 1:128 [midpoint 1:93]. Hence, the range for Israel derived using Swift's indirect approach (estimated from birth rates) is broadly consistent with direct surveys. Conclusions: The FA carrier frequency in the US may be higher than previously thought, around 1:200 or perhaps even higher. From the perspective of population genetics, our results suggest there is less difference between the average carrier frequency in the US and higher carrier frequencies of around 1:100 reported for a number of ethnic groups including Ashkenazi Jews. This is consistent with the facts that the general US population is heterogeneous mixture of descendents of many ancestral groups, and FA is found world-wide. Our results also suggest that some European populations may have higher carrier frequencies than currently recognized. Our findings are sensitive to a number of assumptions. Going forwards, large scale re-sequencing studies could more precisely determine how many persons in the general population carry causative alleles for FA and other rare recessive syndromes. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Wildfire severity reduces richness and alters composition of soil fungal communities in boreal forests of western Canada

2021 ◽  
Author(s):  
Nicola Day ◽  
KE Dunfield ◽  
JF Johnstone ◽  
MC Mack ◽  
MR Turetsky ◽  
...  
Keyword(s):  
Community Structure ◽  
Community Composition ◽  
Fungal Community ◽  
Boreal Forests ◽  
Fire Severity ◽  
Fungal Communities ◽  
Organic Layer ◽  
Fungal Community Structure ◽  
Soil Organic Layer ◽  
Total Fungi

© 2019 John Wiley & Sons Ltd Wildfire is the dominant disturbance in boreal forests and fire activity is increasing in these regions. Soil fungal communities are important for plant growth and nutrient cycling postfire but there is little understanding of how fires impact fungal communities across landscapes, fire severity gradients, and stand types in boreal forests. Understanding relationships between fungal community composition, particularly mycorrhizas, and understory plant composition is therefore important in predicting how future fire regimes may affect vegetation. We used an extreme wildfire event in boreal forests of Canada's Northwest Territories to test drivers of fungal communities and assess relationships with plant communities. We sampled soils from 39 plots 1 year after fire and 8 unburned plots. High-throughput sequencing (MiSeq, ITS) revealed 2,034 fungal operational taxonomic units. We found soil pH and fire severity (proportion soil organic layer combusted), and interactions between these drivers were important for fungal community structure (composition, richness, diversity, functional groups). Where fire severity was low, samples with low pH had higher total fungal, mycorrhizal, and saprotroph richness compared to where severity was high. Increased fire severity caused declines in richness of total fungi, mycorrhizas, and saprotrophs, and declines in diversity of total fungi and mycorrhizas. The importance of stand age (a surrogate for fire return interval) for fungal composition suggests we could detect long-term successional patterns even after fire. Mycorrhizal and plant community composition, richness, and diversity were weakly but significantly correlated. These weak relationships and the distribution of fungi across plots suggest that the underlying driver of fungal community structure is pH, which is modified by fire severity. This study shows the importance of edaphic factors in determining fungal community structure at large scales, but suggests these patterns are mediated by interactions between fire and forest stand composition.

Quality Control of Data in a Large-Scale Cancer Register Program

1966 ◽  
Vol 05 (02) ◽  
pp. 67-74 ◽  
Author(s):  
W. I. Lourie ◽  
W. Haenszeland
Keyword(s):  
United States ◽  
Quality Control ◽  
Cancer Patients ◽  
Large Scale ◽  
The United States ◽  
Newly Diagnosed ◽  
Related Data ◽  
Cancer Register ◽  
Independent Review ◽  
End Results

Quality control of data collected in the United States by the Cancer End Results Program utilizing punchcards prepared by participating registries in accordance with a Uniform Punchcard Code is discussed. Existing arrangements decentralize responsibility for editing and related data processing to the local registries with centralization of tabulating and statistical services in the End Results Section, National Cancer Institute. The most recent deck of punchcards represented over 600,000 cancer patients; approximately 50,000 newly diagnosed cases are added annually.Mechanical editing and inspection of punchcards and field audits are the principal tools for quality control. Mechanical editing of the punchcards includes testing for blank entries and detection of in-admissable or inconsistent codes. Highly improbable codes are subjected to special scrutiny. Field audits include the drawing of a 1-10 percent random sample of punchcards submitted by a registry; the charts are .then reabstracted and recoded by a NCI staff member and differences between the punchcard and the results of independent review are noted.

Temporal dynamics of mycorrhizal fungal communities and co-associations with grassland plant communities following experimental manipulation of rainfall

2019 ◽  
Author(s):  
Coline Deveautour ◽  
Sally Power ◽  
Kirk Barnett ◽  
Raul Ochoa-Hueso ◽  
Suzanne Donn ◽  
...  
Keyword(s):  
Community Composition ◽  
Plant Community ◽  
Plant Communities ◽  
Fungal Community ◽  
Mycorrhizal Fungi ◽  
Temporal Dynamics ◽  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Plant Responses ◽  
Rainfall Regimes

Climate models project overall a reduction in rainfall amounts and shifts in the timing of rainfall events in mid-latitudes and sub-tropical dry regions, which threatens the productivity and diversity of grasslands. Arbuscular mycorrhizal fungi may help plants to cope with expected changes but may also be impacted by changing rainfall, either via the direct effects of low soil moisture on survival and function or indirectly via changes in the plant community. In an Australian mesic grassland (former pasture) system, we characterised plant and arbuscular mycorrhizal (AM) fungal communities every six months for nearly four years to two altered rainfall regimes: i) ambient, ii) rainfall reduced by 50% relative to ambient over the entire year and iii) total summer rainfall exclusion. Using Illumina sequencing, we assessed the response of AM fungal communities sampled from contrasting rainfall treatments and evaluated whether variation in AM fungal communities was associated with variation in plant community richness and composition. We found that rainfall reduction influenced the fungal communities, with the nature of the response depending on the type of manipulation, but that consistent results were only observed after more than two years of rainfall manipulation. We observed significant co-associations between plant and AM fungal communities on multiple dates. Predictive co-correspondence analyses indicated more support for the hypothesis that fungal community composition influenced plant community composition than vice versa. However, we found no evidence that altered rainfall regimes were leading to distinct co-associations between plants and AM fungi. Overall, our results provide evidence that grassland plant communities are intricately tied to variation in AM fungal communities. However, in this system, plant responses to climate change may not be directly related to impacts of altered rainfall regimes on AM fungal communities. Our study shows that AM fungal communities respond to changes in rainfall but that this effect was not immediate. The AM fungal community may influence the composition of the plant community. However, our results suggest that plant responses to altered rainfall regimes at our site may not be resulting via changes in the AM fungal communities.

Utopias of One

2019 ◽  
Author(s):  
Joshua Kotin
Keyword(s):  
United States ◽  
Soviet Union ◽  
World War I ◽  
Large Scale ◽  
Jim Crow ◽  
Personal Autonomy ◽  
The United States ◽  
Soviet Period ◽  
Original Research ◽  
The Soviet Union

This book is a new account of utopian writing. It examines how eight writers—Henry David Thoreau, W. E. B. Du Bois, Osip and Nadezhda Mandel'shtam, Anna Akhmatova, Wallace Stevens, Ezra Pound, and J. H. Prynne—construct utopias of one within and against modernity's two large-scale attempts to harmonize individual and collective interests: liberalism and communism. The book begins in the United States between the buildup to the Civil War and the end of Jim Crow; continues in the Soviet Union between Stalinism and the late Soviet period; and concludes in England and the United States between World War I and the end of the Cold War. In this way it captures how writers from disparate geopolitical contexts resist state and normative power to construct perfect worlds—for themselves alone. The book contributes to debates about literature and politics, presenting innovative arguments about aesthetic difficulty, personal autonomy, and complicity and dissent. It models a new approach to transnational and comparative scholarship, combining original research in English and Russian to illuminate more than a century and a half of literary and political history.

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