Trace Metal Inventories and Lead Isotopic Composition Chronicle a Forest Fire’s Remobilization of Industrial Contaminants Deposited in the Angeles National Forest

PubMed Central

Odigie, Kingsley O.; Flegal, A. Russell

2014-01-01

The amounts of labile trace metals: [Co] (3 to 11 µg g−1), [Cu] (15 to 69 µg g−1), [Ni] (6 to 15 µg g−1), [Pb] (7 to 42 µg g−1), and [Zn] (65 to 500 µg g−1) in ash collected from the 2012 Williams Fire in Los Angeles, California attest to the role of fires in remobilizing industrial metals deposited in forests. These remobilized trace metals may be dispersed by winds, increasing human exposures, and they may be deposited in water bodies, increasing exposures in aquatic ecosystems. Correlations between the concentrations of these trace metals, normalized to Fe, in ash from the fire suggest that Co, Cu, and Ni in most of those samples were predominantly from natural sources, whereas Pb and Zn were enriched in some ash samples. The predominantly anthropogenic source of excess Pb in the ash was further demonstrated by its isotopic ratios (208Pb/207Pb: 206Pb/207Pb) that fell between those of natural Pb and leaded gasoline sold in California during the previous century. These analyses substantiate current human and environmental health concerns with the pyrogenic remobilization of toxic metals, which are compounded by projections of increases in the intensity and frequency of wildfires associated with climate change. PMID:25259524

Wildfire ash: its production and hydro-eco-geomorphic effects in forested landscapes

NASA Astrophysics Data System (ADS)

Doerr, S. H.; Bodi, M.; Santin, C.; Balfour, V.; Woods, S.; Mataix-Solera, J.; Cerda, A.; Shakesby, R.

2012-12-01

Fire, whether ignited naturally or by humans, is one of the most important disturbance agents in many of the world's forested ecosystems. Amongst its direct consequences is the deposition of a range of solid and largely powdery residues on the ground consisting of charred organic material including charcoal and residual mineral material. This fragile 'ash' layer can be removed in large quantities from hillslopes within days by wind or water erosion, with the latter facilitating its transfer to the hydrological system. Probably as a result of its ephemeral nature and not being soil, vegetation or litter, ash has seen limited attention in studies on hydrological impacts of wildfire. Those few studies available show that ash can substantially affect the hydrological system. When present on hillslopes as a water-absorbent layer, it can reduce surface runoff, protect soil against rainsplash erosion, and its leachates can reportedly reduce soil erodibility by promoting flocculation of dispersed clays. In contrast, however, ash can also increase surface runoff by blocking soil pores or by forming a crust. Furthermore, ash is thought capable of promoting debris flows. Its net effect probably depends on the nature of the ash and soil including their respective water repellency levels, the pore size distribution of the soil, and general terrain and rainfall characteristics. Being very mobile, ash can be the source of substantial organic and inorganic sediment inputs, and of solute influxes into the fluvial system. These can affect water quality sometimes with detrimental effects on aquatic organisms and domestic water supply. This presentation aims to provide an overview of the current knowledge base regarding the production and potential effects of wildfire ash on the hydrological system in and beyond forested landscapes..The late Scott Woods examining a thick ash layer following a severe fire in a conifer forest. Montana, USA.

Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula

USGS Publications Warehouse

Pereira, P.; beda, X.; Martin, D.; Mataix-Solera, J.; Guerrero, C.

2011-01-01

Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO2) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40??70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (p<0.001), water-soluble Ca, Mg, Na, SiO2 and TS and a decrease in water-soluble Mn, Fe and Zn. Differences were identified between oak species for water-soluble K, Al and Fe. In Q.S samples we registered a significant increase in the first two elements p<0.001 and p<0.01, respectively, and a non-significant impact in the third, at p<0.05. In Q.R data we identified a non-significant impact on water-soluble K and Al and a significant decrease in water-soluble Fe (p<0.05). These differences are probably due to vegetation characteristics and burn severity. The fire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed fire will improve soil nutrient status without causing soil degradation and thus is considered to be a good management strategy. ?? 2010 Elsevier Inc.

Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula.

PubMed

Pereira, Paulo; Ubeda, Xavier; Martin, Deborah; Mataix-Solera, Jorge; Guerrero, César

2011-02-01

Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO(2)) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40×70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (p<0.001), water-soluble Ca, Mg, Na, SiO(2) and TS and a decrease in water-soluble Mn, Fe and Zn. Differences were identified between oak species for water-soluble K, Al and Fe. In Q.S samples we registered a significant increase in the first two elements p<0.001 and p<0.01, respectively, and a non-significant impact in the third, at p<0.05. In Q.R data we identified a non-significant impact on water-soluble K and Al and a significant decrease in water-soluble Fe (p<0.05). These differences are probably due to vegetation characteristics and burn severity. The fire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed fire will improve soil nutrient status without causing soil degradation and thus is considered to be a good management strategy. Copyright © 2010 Elsevier Inc. All rights reserved.

Fire vegetative ash and erosion in the Mediterranean areas. State of the art and future perspectives

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerdà, Artemi

2013-04-01

Fire is a global phenomenon with important ecological impacts. Among all ecosystems, the Mediterranean is frequently visited by severe wildfires with serious impacts on soil properties and increase soil vulnerability to erosion due vegetation removal. After the fire the ash distributed in soil surface can mitigate soil exposition to erosion and rain splash (Cerda and Doerr, 2008), however, this depends on the fire severity that have implications on the type of ash produced (Pereira et al., 2010). High fire severities produced thinner ash that it is easily transported by wind, contrary to low severity wildfires where combustion is not so intense and the mass loss is less, providing a better soil protection in the immediate period after the fire. Soil protection after the fire highly depends on fire severity (Pereira et al. 2013a; Pereira et al. 2013b). Ash it is a highly mobile material, thus this protection can change in space and time, providing a better cover in some areas and worst in others. In the period immediate after the fire, ash can change soil hydrological properties, increasing water retention and reducing sediment transport in relation to bare soil areas (Cerda and Doerr, 2008), but also clog soil pores, seal the soil and increase erosion (Onda et al., 2008). In fact results are controversial and the impacts of vegetative ash in soil erosion may rely on the proprieties of ash produced, that can be extremely variable, even in small distances (Pereira and Úbeda, 2010), due the different conditions of combustions. Ash produced at low severity temperatures can be highly hydrophilic (Bodi et al., 2011) and induce soil hydrophobicity (Bodi et al., 2012). Other mechanisms as the direct impact of fire in soil, can induce soil water repellency, and do not have any interference of vegetative ash. This fire can induce direct (e.g temperature) and indirect (e.g. ash properties) on soil wettability, with obvious implications on spatio-temporal pattern of soil erosion. At this point we are dealing with a complex interaction since interactions, since low severity fires due ash, and high severity fires, due temperature induce soil hydrophobicity. After the fire, other ash properties may interact with soil erosion, as particulate size, and chemical composition, that can induce soil particulates flocculation or dispersion. Ash chemistry is strongly related with fire severity (Pereira et al., 2012). Further studies may be directed in the complex interaction between ash physico-chemical properties interaction with the degree of fire impacts on soil. These and other ideas will be discussed during the session. Acknowledgements, The authors appreciated the support of the project "Litfire", Fire effects in Lithuanian soils and ecosystems (MIP-048/2011) funded by the Lithuanian Research Council and FUEGORED (Spanish Network of Forest Fire Effects on Soils http://grupo.us.es/fuegored/). References Bodi, M., Doerr, S., Cerdà, A., Mataix-Solera, J. (2012) Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma 191: 14-13. Bodi, M., Mataix-Solera, J., Doerr, S., Cerdà, A. (2011) The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic matter content. Geoderma, 160, 599-607. Cerdà, A., Doerr, S.H. (2008). The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74, 256-263. Onda Y, Dietrich WE, Booker F. 2008. Evolution of overland flow after a severe forest fire, Point Reyes, California. Catena. 72, 13-20. Pereira, P., Bodi. M., Úbeda, X., Cerdà, A., Mataix-Solera, J., Balfour, V, Woods, S. (2010) Las cenizas y el ecosistema suelo, In: Cerdà, A. Jordan, A. (eds) Actualización en métodos y técnicas para el estudio de los suelos afectados por incendios forestales, 345-398. Càtedra de Divulgació de la Ciència. Universitat de Valencia. ISBN: 978-84-370-7887-8. Deposito Legal: V-3541-2010. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2013a) Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development, (In Press), DOI: 10.1002/ldr.2195 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Jordan, A. Burguet, M. (2013b) Effects of fire on ash thickness in a Lithuanian grassland and short-term spatio-temporal changes, Solid Earth Discussions,4, 1545-1584. Pereira, P., Úbeda, X. (2010) Spatial variation of heavy metals released from ashes after a wildfire, Journal of Environmental Engineering and Landscape Management 18(1), 13-22. Pereira, P., Úbeda, X., Martin, D. (2012) Fire severity effects on ash chemical composition and water-extractable elements, Geoderma, 191, 105-114.

The ash in forest fire affected soils control the soil losses. Part 2. Current and future research challenges

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerdà, Artemi

2013-04-01

Ash distribution on soil surface and impacts on soil properties received a great attention in recently (Pereira et al., 2010; Pereira et al., 2013). Ash it is a highly mobile material that can be easily transported wind, especially in severe wildland fires, where organic matter is reduced to dust, due the high temperatures of combustion. In the immediate period after the fire, ash cover rules soil erosion as previous researchers observed (Cerdà, 1998a; 1998b) and have strong influence on soil hydrological properties, such as water retention (Stoof et al. 2011 ) and wettability (Bodi et al., 2011). Ash it is also a valuable source of nutrients important for plant recuperation (Pereira et al., 2011; Pereira et al., 2012), but can act also as a source contamination, since are also rich in heavy metals (Pereira and Ubeda, 2010). Ash has different physical and chemical properties according the temperature of combustion, burned specie and time of exposition (Pereira et al., 2010). Thus this different properties will have different implications on soil properties including erosion that can increase due soil sealing (Onda et al. 2008) or decrease as consequence of raindrop impact reduction (Cerdà and Doerr, 2008). The current knowledge shows that ash has different impacts on soil properties and this depends not only from the type of ash produced, but of the soil properties (Woods and Balfour, 2010). After fire wind and water strong redistribute ash on soil surface, increasing the vulnerability of soil erosion in some areas, and reducing in others. Understand this mobility is fundamental have a better comprehension about the spatial and temporal effects of ash in soil erosion. Have a better knowledge about this mobility is a priority to future research. Other important aspects to have to be assessed in the future are how ash particulates percolate on soil and how ash chemical composition is important to induce soil aggregation and dispersion. How soil micro topography have implications on ash spatial distribution and if soil micro topography changes with time? What the factors that controls it? What it is the impact of ash in vegetation recuperation and the implications of this recover in ash spatial distribution? We need studies with better spatial and temporal resolution, especially in the immediate period after the fire, when the major spatial and temporal changes on ash distribution and impacts occur. Based on high level research conducted by Artemi Cerdà and others, our future research will be focused in these and other aspects in order to have a better knowledge about the impacts of ash on post-fire spatio-temporal erosion. Acknowledgements, Lithuanian Research Council. Project LITFIRE, Fire effects on Lithuanian soils and ecosystems (MIP-48/2011) and the research projects GL2008-02879/BTE and LEDDRA 243857. References Bodí, M., Mataix-Solera, J., Doerr, S., and Cerdà, A. 2011b. The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma, 160, 599-607. Cerdà, A. 1998a. Postfire dynamics of erosional processes under mediterranean climatic conditions. Z. Geomorphol., 42 (3) 373-398. Cerdà, A. 1998b. Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland.Hydrological Processes, 12, 1031-1042. Cerdà, A., and Doerr, S.H. 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74, 256-263. Onda, Y., Dietrich W. E., and Booker, F. 2008. Evolution of overland flow after severe forest fire, Point Reyes, California, Catena, 72, 13-20. Pereira, P. Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. 2013. Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development, (In press) Pereira, P., Bodi. M., Úbeda, X., Cerdà, A., Mataix-Solera, J., Balfour, V, Woods, S. 2010. Las cenizas y el ecosistema suelo, In: Cerdà, A. Jordan, A. (eds) Actualización en métodos y técnicas para el estudio de los suelos afectados por incendios forestales, 345-398. Càtedra de Divulgació de la Ciència. Universitat de Valencia. ISBN: 978-84-370-7887-8. Deposito Legal: V-3541-2010. Pereira, P., Úbeda, X. 2010. Spatial variation of heavy metals released from ashes after a wildfire, Journal of Environmental Engineering and Landscape Management, 18(1), 13-22. Pereira, P., Ubeda, X., Martin, D. 2012. Fire severity effects on ash chemical composition and water-extractable elements, Geoderma, 191, 105-114. Pereira, P., Úbeda, X., Martin, D., Mataix-Solera, J., Guerrero, C. 2011. Effects of a low prescribed fire in ash water soluble elements in a Cork Oak (Quercus suber) forest located in Northeast of Iberian Peninsula, Environmental Research, 111(2), 237-247. Stoff, C.R., Wesseling, J.G., Ritsema, C.J. 2011. Effects of ash on soil water retention, Geoderma, 159(3-4), 276-285. Woods, S.W., Balfour, V.N. 2010. The effects of soil texture and ash thickness on the post-fire hydrological response from ash-covered soils, Journal of Hydrology, 393, 274-286.

Forest fire in the central Himalaya: climate and recovery of trees

NASA Astrophysics Data System (ADS)

Sharma, Subrat; Rikhari, H. C.

A forest fire event is influenced by climatic conditions and is supported by accumulation of fuel on forest floor. After forest fire, photosynthetically active solar radiation was reduced due to accumulation of ash and dust particles in atmosphere. Post-fire impacts on Quercus leucotrichophora, Rhododendron arboreum and Lyonia ovalifolia in a broadleaf forest were analysed after a wild fire. Bark depth damage was greatest for L. ovalifolia and least for Q. leucotrichophora. Regeneration of saplings was observed for all the tree species through sprouting. Epicormic recovery was observed for the trees of all the species. Young trees of Q. leucotrichophora (<40 cm circumference at breast height) were susceptible to fire as evident by the lack of sprouting. Under-canopy tree species have a high potential for recovery as evident by greater length and diameter of shoots and numbers of buds and leaves per shoot than canopy species. Leaf area, leaf moisture and specific leaf area were greater in the deciduous species, with few exceptions, than in evergreen species.

An arthropod survival strategy in a frequently burned forest

Treesearch

Jane Dell; Joseph O' Brien; Lydia Doan; Lora Richards; Lee Dyer

2017-01-01

The sound of burning stems and leaves filled our ears and smoke swirled as we marched into the longleaf pine forest to assess the experimental burn. As we walked over the ash of burned vegetation, seedbanks and plant parts lay beneath our feet waiting to grow. But what we couldn’t see were the arthropods fleeing the fire. How are these invertebrates adapted to fire?...

Forest health conditions in North America

Treesearch

B. Moody; J.V. Castillo; M.E. Fenn

2008-01-01

Some of the greatest forest health impacts in North America are caused by invasive forest insects and pathogens (e.g., emerald ash borer and sudden oak death in the US), by severe outbreaks of native pests (e.g., mountain pine beetle in Canada), and fires exacerbated by changing climate. Ozone and N and S pollutants continue to impact the health of forests in several...

Wildland fire ash: future research directions

NASA Astrophysics Data System (ADS)

Bodí, Merche B.; Martins, Deborah A.; Cerdà, Artemi; Balfour, Victoria N.; Santin, Cristina; Doerr, Stefan H.; Pereira, Paulo; Mataix-Solera, Jorge

2014-05-01

Ash is a key component of the forest fires affected land (Cerdà, 1998; Bodí et al., 2011; Pereira et al., 2013a). Ash controls the hydrological processes and determines the water repellency (Dlapa et al., 2012) and the infiltration rates (Cerdà and Doerr, 2008;). Moreover, ash is the key factor on runoff initiation and then on the soil erosion. Little is known about the impact of ash in different ecosystems, but during the last decade a substantial increase in the papers that show the role of ash in the Earth and Soil System were published (Bodí et al., 2012; Pereira et al., 2013b).. Ash is being found as the key component of the post-fire pedological, geomorphological and hydrological response after forest fires (Fernández et al., 2012; Martín et al., 2012; Bodí et al., 2013; Guénon et al., 2013; Pereira et al., 2013c). A recent State-of-the-Art review about wildland fire ash (Bodí et al., 2014) compiles the knowledge regarding the production, composition and eco-hydro-geomorphic effects of wildland fire ash. In the present paper we indicate the knowledge gaps detected and suggest topics that need more research effort concerning: i) data collection and analysis techniques: a) To develop standardized sampling techniques that allow cross comparison among sites and avoid inclusion of the underlying soil unless the burned surface soil forms part of the ash layer, b) To develop standardized methods to define and characterize ash, including its color, physical properties such as particle size distribution or density, proportion of pyrogenic C, chemical and biological reactivity and persistence in the environment, c) To validate, calibrate and test measurements collected through remote sensing with on-the-ground measurements. ii) ash production, deposition redistribution and fate: d) To untangle the significance of the effects of maximum temperature reached during combustion versus the duration of heating, e) To understand the production of ash by measuring its depth, density, and size fraction distribution compared to that of the underlying soil, f) To measure the spatial variability of ash at the plot or hillslope scale, g) To address issues of how much ash stays on site after fire, especially how much is incorporated into underlying soil layers, compared to how much is eroded by wind and water and becomes incorporated into depositional environments located away from the site. iii) ash effects h) To study the connectivity of patches of ash to make progress in understanding the role of ash in infiltration, the generation of runoff and erosion, i) To take into account the role of ash in the fate of the ecosystem immediately after the fire, as well as the combination of ash and other cover, such as the needles, in the post-fire period, j) To study the amount and forms of C in ash, including studies characterizing its chemical and biological reactivity and degradability in soil and sedimentary environments, k) To understanding the legacy of atmospherically-deposited elements (e.g. P, Si, Mn) and dust to fully understand the complex chemistry of ash, and at the same time assess its effects on human health. iii) enhance collaboration across the globe on the multidisciplinary topic of ash research since research in large areas of the world that burn (e.g., Africa and Russia) is underrepresented. We are sure that several activities, such as land and water supply management, risk reduction, and planning for societal and ecosystem resilience in the face of a changing climate, will benefit from the insights gained from the ash research community. Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and RECARE FP7 project 603498 supported this research. References: Bodí, M. B., Mataix-Solera, J., Doerr, S. H., Cerdà, A. 2011.The wettability of ash from burned vegetation and its relatioship to Mediterranean plant species type, burn. Geoderma 160: 599-607. Bodí, M.B. Doerr, S.H., Cerdà, A. and Mataix-Solera, J. 2012. Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soils. Geoderma, 191, 14-23. http://dx.doi.org/10.1016/j.geoderma.2012.01.006 Bodí, M.B., Muñoz-Santa, I., Armero, C., Doerr, S.H., Mataix-Solera, J., Cerdà, A. 2013. Spatial and temporal variations of water repellency and probability of its occurrence in calcareous Mediterranean rangeland soils affected by fires. Catena, 108, 14-24. http://dx.doi.org/10.1016/j.catena.2012.04.002 Bodí, Merche B., Martin, Deborah A., Balfour, Victoria N., Santín, Cristina, Doerr, Stefan H., Pereira, Paulo, Cerdà, Artemi, Mataix-Solera, Jorge, Wildland fire ash: Production, composition and eco-hydro-geomorphic effects, Earth Science Reviews (2014), doi: 10.1016/j.earscirev.2013.12.007 Cerdà, A. 1998. Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes, 12, 1031-1042. Cerdà, A. y Doerr, S.H. 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74 , 256- 263. doi:10.1016/S0341-8162(02)00027-9 Dlapa, P., Bodí, M.B., Mataix-Solera, J., Cerdà, A., &, Doerr, S.H. 2013. FT-IR spectroscopy reveals that ash water repellency is highly dependent on ash chemical composition. Catena, 108, 35-43. Doi:10.1016/j.catena.2012.02.011 Fernández, C., Vega, J. A., Jiménez, E., Vieira, D. C. S., Merino, A., Ferreiro, A., Fonturbel, T. 2012. Seeding and mulching + seeding effects on post-fire runoff, soil erosion and species diversity in Galicia (NW Spain). Land Degradation & Development, 23: 150- 156. DOI 10.1002/ldr.1064 Guénon, R., Vennetier, M., Dupuy, N., Roussos, S., Pailler, A., Gros, R. 2013. Trends in recovery of Mediterranean soil chemical properties and microbial activities after infrequent and frequent wildfires. Land Degradation & Development, 24: 115- 128. DOI 10.1002/ldr.1109 Martín, A., Díaz-Raviña, M., Carballas, T. 2012. Short- and medium-term evolution of soil properties in Atlantic forest ecosystems affected by wildfires. Land Degradation & Development, 23: 427- 439. DOI 10.1002/ldr.1078 Pereira, P., Úbeda, X., Martin, D., Mataix-Solera, J., Cerdà, A., Burguet, M. 2013a. Wildfire effects on extractable elements in ash from a Pinus pinaster forest in Portugal, Hydrological Processes, DOI: 10.1002/hyp.9907 Pereira, P., Cerda, A., Jordan, A., Bolutiene, V., Pranskevicius, M., Ubeda, X., Mataix-Solera, J. 2013b. Spatio-temporal vegetation recuperation after a grassland fire in Lithuania, Procedia Environmental Sciences, 19, 856-864. DOI:10.1016/j.proenv.2013.06.095. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Martin, D., Jordan, A. and Burguet, M. 2013c. Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania. Solid Earth, 4, 153-165. www.solid-earth.net/4/153/2013/ doi:10.5194/se-4-153-2013

Chemical and physical properties of cyclone fly ash from the grate-fired boiler incinerating forest residues at a small municipal district heating plant (6MW).

PubMed

Pöykiö, R; Rönkkömäki, H; Nurmesniemi, H; Perämäki, P; Popov, K; Välimäki, I; Tuomi, T

2009-03-15

In Finland, the new limit values for maximal allowable heavy metal concentrations for materials used as an earth construction agent came into force in July 2006. These limit values are applied if ash is utilized, e.g. in roads, cycling paths, pavements, car parks, sport fields, etc. In this study we have determined the most important chemical and physical properties of the cyclone fly ash originating from the grate-fired boiler incinerating forest residues (i.e. wood chips, sawdust and bark) at a small municipal district heating plant (6 MW), Northern Finland. This study clearly shows that elements are enriched in cyclone fly ash, since the total element concentrations in the cyclone fly ash were within 0.2-10 times higher than those in the bottom ash. The total concentrations of Cd (25 mg kg(-1); d.w.), Zn (3630 mg kg(-1); d.w.), Ba (4260 mg kg(-1); d.w.) and Hg (1.7 mg kg(-1); d.w.) exceeded the limit values, and therefore the cyclone fly ash cannot be used as an earth construction agent. According to the leached amounts of Cr (38 mg kg(-1); d.w.), Zn (51 mg kg(-1); d.w.) and sulphate (50,000 mg kg(-1); d.w.), the cyclone fly ash is classified as a hazardous waste, and it has to be deposited in a hazardous waste landfill.

Distribution of polycyclic aromatic hydrocarbons in riverine waters after Mediterranean forest fires.

PubMed

Olivella, M A; Ribalta, T G; de Febrer, A R; Mollet, J M; de Las Heras, F X C

2006-02-15

Extensive forest fires occurred in Catalonia, northern Spain, in 1994. In our study, concentrations and profiles of 12 parent polycyclic aromatic hydrocarbons (PAHs) were determined in riverine waters, ash and sediment samples at nine sampling sites (W1-W9) and at three sampling dates from Llobregat hydrographic basin: in August, 1994, one month after the extensive forest fires; in September, 1994, after the first heavy autumn rainfalls and in January, 1995, six months after forest fires. In August 1994, the total concentrations of 12 PAHs measured in riverine waters varied from 2 ng/l to 336 ng/l. In September 1994, the total PAH concentrations decreased to 0.2-31 ng/l and in January 1995, from 9 ng/l to 73 ng/l. In August, the composition pattern of PAHs showed a distribution dominated by 4-ring PAHs (pyrene, chrysene+triphenylene, benzo(a)anthracene) at W3-W6, W8 and W9 and 3-ring PAHs (phenanthrene) at W1, W2 and W7. In September, a preference by 3-ring PAHs (phenanthrene) at all sampling sites except W5 was shown and in January was clearly dominated by 4-ring PAHs (chrysene+triphenylene, pyrene, benzo(a)anthracene) at all sampling sites. In ash and sediment samples, the total concentrations of 12 PAHs ranged from 1.3 ng/g to 19 ng/g. The dominant compound was phenanthrene.

The effects of fire temperatures on water soluble heavy metals.

NASA Astrophysics Data System (ADS)

Pereira, P.; Ubeda, X.; Martin, D. A.

2009-04-01

Fire ash are majority composed by base cations, however the mineralized organic matter, led also available to transport a higher quantity of heavy metals that potentially could increase a toxicity in soil and water resources. The amount availability of these elements depend on the environment were the fire took place, burning temperature and combusted tree specie. The soil and water contamination from fire ash has been neglected, because the majority of studies are focused on base cations dynamic. Our research, beside contemplate major elements, is focused in to study the behavior of heavy metals released from ash slurries created at several temperatures under laboratory environment, prescribed fires and wildland fires. The results presented in these communication are preliminary and study the presence of Aluminium (Al3+), Manganese (Mn2+), Iron (Fe2+) and Zinc (Zn2+) of ash slurries generated in laboratory environment at several temperatures (150°, 200°, 250°, 300°, 350°, 400°,450°, 500°, 550°C) from Quercus suber, Quercus robur, Pinus pinea and Pinus pinaster and from a low medium temperature prescribed fire in a forest dominated Quercus suber trees. We observed that ash produced at lower and medium temperatures (<300-400°C) released in water higher contents of Al3+ than unburned sample, especially in Quercus species and Mn2+ in Pinus ashes. Fe2+ and Zn2+ showed a reduced concentration in test solution in relation to unburned sample at all temperatures of exposition. In the results obtained from prescribed fire, we identify a higher release of Al3+ and a decrease of the remain elements. The solubilization of these elements are related with pH levels and ash calcite content, because their ability to capture ions in solution. Moreover, the amount and the type of ions released in relation to unburned sample vary in each specie. In this study Al3+ release is related with Quercus species and Mn2+ with Pinus species. Fire ashes can be an environmental problem, because at long term can increase soil acidity. After all base cations have being leached, pH values decrease, and the heavy metals remaining in the ash are easily transported with unknown impacts on soil and water resources. Research is needed in the study at long term of the effects of fire in metals accumulation in soil resources, and all these aspects will be discussed. Keywords: Fire ash, heavy metals, Quercus suber, Quercus robur, Pinus pinea, Pinus pinaster, prescribed fire, pH, Calcite

The formation of fire residues associated with hunter-gatherers in humid tropical environments: A geo-ethnoarchaeological perspective

NASA Astrophysics Data System (ADS)

Friesem, David E.; Lavi, Noa; Madella, Marco; Boaretto, Elisabetta; Ajithparsad, P.; French, Charles

2017-09-01

Tropical forests have been an important human habitat and played a significant role in early human dispersal and evolution. Likewise, the use of fire, besides being one of the exceptional characteristics of humans, serves as a marker for human evolution. While the use of fire by prehistoric hunter-gatherers is relatively well documented in arid and temperate environments, the archaeological evidence in humid tropical environment is to date very limited. We first review the archaeological evidence for hunter-gatherer use of fire in humid tropical environments and suggest that better understanding of formation processes is required. We present a geo-ethnoarchaeological study from South India, involving ethnography, excavations and laboratory-based analyses in order to build a new framework to study fire residues in humid tropical forests associated with hunter-gatherer's use of fire. Ethnographic observations point to a dynamic and ephemeral use of hearths. Hearths location were dictated by the social and ever-changing social dynamics of the site. The hearths deposited small amount of residues which were later swept on a daily basis, re-depositing ash and charcoal in waste areas and leaving only a microscopic signal in the original location. Particular acidic conditions and intensive biological activity within tropical sediments result in the complete dissolution of ash and bones while favouring the preservation of charcoal and phytoliths. Consequently, the identification of fire residues in humid tropical forests and the reconstruction of the human use of fire must involve multi-proxy microscopic analysis to detect its micro-signatures.

Causes of Variability in the Effects of Vegetative Ash on Post-Fire Runoff and Erosion

NASA Astrophysics Data System (ADS)

Balfour, V.; Woods, S.

2008-12-01

Vegetative ash formed during forest wildfires has varying effects on post-fire runoff and erosion. In some cases the ash layer reduces runoff and erosion by storing rainfall and by protecting the soil surface from surface sealing and rainsplash detachment. In other cases, the ash layer increases runoff and erosion by forming a surface crust, clogging soil pores, and providing a ready source of highly erodible fine material. Since only a handful of studies have measured the hydrogeomorphic effect of ash, it is unclear whether the observed variability in its effect reflects initial spatial variability in the ash properties due to factors such as fuel type and fire severity, or differences that develop over time due to compaction and erosion or exposure of the ash to rainfall and air. The goal of our research was to determine if the observed differences in the effect of ash on runoff and erosion are due to: 1) variability in initial ash hydrologic properties due to differences in combustion temperature and fuel type, or 2) variability in ash hydrologic properties caused by mineralogical phase changes that develop after the ash is exposed to water. We created ash in the laboratory using wood and needles of Lodgepole pine (Pinus contorta), Ponderosa pine (Pinus Ponderosa) and Douglas fir (Pseudotsuga menziesii) and at 100° C temperature increments from 300 to 900° C. A subsample of ash from each fuel type / temperature combination was saturated, left undisturbed for 24 hours and then oven dried at 104° C. Dry and wetted ash samples were characterized in terms of: structure (using a scanning electron microscope), carbon content, mineralogy (using X-ray diffraction), porosity, water retention properties and hydraulic conductivity. Ash produced at the higher combustion temperatures from all three fuel types contained lime (CaO), which on wetting was transformed to portlandite (Ca(OH)2) and calcite (CaCO3). This mineralogical transformation resulted in irreversible hardening and crusting of the ash, and hardened ash had a significantly lower hydraulic conductivity than unhardened ash. Ash produced by high severity fires may undergo this same hardening and crusting process after it is wetted by rainfall whereas ash produced by lower severity fires will not, and this may explain in part the contrasting hydrogeomorphic effects of ash that have been reported in the literature.

Prescription Fire and Anion Retention in Tahoe Forest Soils

USDA-ARS?s Scientific Manuscript database

Prescribed burning is a possible option to reduce fire potential in the Lake Tahoe Basin (California and Nevada). However, subsequent nutrient loading to the lake is a major concern. The effect of residual ash on anion leaching, primarily O-PO4 and SO42-, was studied in both the field and laboratory...

Analyzing the vegetation response under different treatments after wildfires in NE Spain

NASA Astrophysics Data System (ADS)

León, Javier; Cerdà, Artemi; Badía, David; Echeverría, Maite; Martí, Clara

2014-05-01

Fire is a natural factor of landscape evolution in Mediterranean ecosystems. The socio-economic changes that occurred in the last decades have contributed to an increase in forest fires (Shakesby, 2011). There was found a change in the fire regimes in terms of frequency, size, seasonality, recurrence as well as fire intensity and severity (Keeley, 2009), which resulted in severe effects on soils, water and vegetation (Guénon et al., 2013). Fire affects soil properties directly by the heat impact (Aznar et al., 2013), and the ash cover (Cerdà and Doerr, 2008) and the reduction of the plant cover (Neary et al., 1999). The lack of vegetation and the heating promotes changes in the soil organic matter content (González-Pérez et al., 2004), on the structural stability (Mataix-Solera et al., 2011), on the hydrophobic response (Bodí et al., 2012), and on the infiltration capacity (Cerdà, 1998a). This is why the vegetation cover and the litter are key factors on soil erosion after forest fires (Prats et al., 2013). Besides, the ash plays an important paper in the soil protection after the forest fire and after the first storms and winds (León et al., 2013; Pereira et al., 2013). The objective of this experiment is to asses the vegetation response after a forest fire and the impact of vegetation recovery on soil erosion. The experiment consisted in a sampling of a linear transect of 10 m with samples each 2 m, under different slope position and aspect. To measure the soil erosion rates we used rainfall simulation experiments (León et al., 2013). The experiments were carried in Castejón (UTM 30T, X671106, Y4644584) in a forest burned in 2008, in the Zuera Mountains, both located in the north of Zaragoza province (NE Spain). The soils on limestone parent material are Rendzic Phaeozem (IUSS, 2007) and the texture of Ah horizons of soils developed on limestone is sandy-loam (Badía et al., 2013). The result shows fast and successful vegetation regeneration in the north-facing slopes, and a delayed recovery on the south-facing slopes. The soil erosion control treatments shown a very efficient response when Chipped branches covered the soil. References Aznar, J.M., González-Pérez, J.A., Badía, D., Martí, C. 2013. At what depth are the properties of a Gypseous forest topsoil affected by burning?. Land Degradation and Development, DOI: 10.1002/ldr.2258 Badía, D., Martí, C., Aznar, J.M., León, J. 2013. Influence of slope and parent rock on soil genesis and classification in semiarid mountainous environments. Geoderma 193-194: 13-21, doi: http://dx.doi.org/10.1016/j.geoderma.2012.10.020. Bodí, M.B., Doerr, S.H., Cerdà, A., and Mataix-Solera, J. 2012. Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma, 191: 14-23. Cerdà, A. 1998a. Postfire dynamics of erosional processes under mediterranean climatic conditions. Zeitschrift für Geomorphologie, 42 (3) 373-398. Cerdà, A. 1998b. The influence of aspect and vegetation on seasonal changes in erosion under rainfall simulation on a clay soil in Spain. Canadian Journal of Soil Science 78, 321-330. Cerdà, A., Doerr, S.H., 2008. The effect of ash and needle cover on surface runoff and ersion in the inmediate post-fire period. Catena 74, 256-263. González-Pérez, J.A., González-Vila, F.J., Almendros, G., Knicker, H. 2004. The effect of fire on soil organic matter - a review. Enviroment International, 30: 855-870. Guénon, R., Vennetier, M., Dupuy, N., Roussos, S., Pailler, A., Gros, R. 2013. Trends in recovery of Mediterranean soil chemical properties and microbial activities after infrequent and frequent wildfires. Land Degradation & Development, 24: 115-128, DOI: 10.1002/ldr.1109. Keeley, J.E. 2009. Fire intensity, fire severity and burn severity: a brief review and suggests usage. International Journal of Wildland Fire, 18: 116-126. León, J., Bodí, M.B., Cerdà, A., Badía, D., 2013. The contrasted response of ash to wetting: The effects of ash type, thickness and rainfall events. Geoderma 209-210, 143-152. Mataix-Solera, J., Cerdà, A., Arcenegui, V., Jordán, A., Zavala, L.M., 2011. Fire effects on soil aggregation: a review. Earth-Science Reviews, 109: 44-60. Neary, D.G., Klopatek, C.C., DeBano, L.F., Ffolliot, P. 1999. Fire effects on belowground sustainability: a review and synthesis. Forest Ccol. Manag., 122: 51-71. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Martin, D., Jordán, A., Burguet, M. 2013. Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania. Solid Earth, 4: 153-165. Prats, S.A., Malvar, M.C., Simões-Vieira, D.C., MacDonald, L., and Keizer, J.J. 2013. Effectiveness of hydromulching to reduce runoff and erosion in a recently burnt pine plantation in central Portugal. Land Degradation & Development, DOI: 10.1002/ldr.2236. Shakesby, R.A. 2011. Post-wildfire soil erosion in the Mediterranean: Review and future research directions. Earth Science Reviews, 105, 71-100.

Ash wettability conditions splash erosion in the postfire

NASA Astrophysics Data System (ADS)

Gordillo-Rivero, Ángel J.; de Celis, Reyes; García-Moreno, Jorge; Jiménez-Compán, Elizabeth; Alanís, Nancy; Cerdà, Artemi; Pereira, Paulo; Zavala, Lorena M.; Jordán, Antonio

2015-04-01

1. INTRODUCTION Soil sustainability and recovery after fire depend on physical, chemical and biological processes and fire severity (Neary et al., 1999; Mataix-Solera and Guerrero, 2007). Fire effects on soils are divided in two types: direct effects, as a consequence of combustion and temperature reached and indirect effects (Neary et al., 1999) as consequence of changes in other ecosystem components, such as decrease in vegetal coverage or ash and partially burned litter contribution including changes in flora (Pausas and Verdú, 2005; Trabaud, 2000). Low intensity fires, during which high temperatures are not reached, affect vegetal coverage but will not cause major impacts on soil. In contrast, prolonged, recurrent, or high-intensity fires may cause important impacts on the soil system functioning (De Celis et al., 2013; DeBano, 1991; Mataix-Solera et al., 2009; Zavala et al., 2014), aggregation (Mataix-Solera et al., 2011), organic matter content and quality (Sevink et al., 1989), water repellency (DeBano, 2000; Doerr et al., 2000), soil nutrients (Stark, 1977), soil erosion (Larsen et al., 2009) and others. In these cases, the restoration period of the initial conditions can be very long and changes may become permanent (DeBano, 1991). During combustion, fuel (biomass, necromass and soil organic matter) is transformed in materials with new physical and chemical properties. After burn, the soil surface is covered by a layer of ash and charred organic residues. Ash has important ecological, hydrological and geomorphological effects, even after being rearranged or mobilized by runoff or wind (Bodí et al., 2014). Ash properties will depend on the burned species, the amount of affected biomass, fuel flammability and structure, temperature and the residence time of thermal peaks (Pereira et al., 2009). Some studies have emphasized the role of ash on soil protection during the after fire period, in which the vegetable coverage could be drastically decreased (Cerdà and Doerr, 2008; Woods and Balfour, 2008; Zavala et al., 2009). The presence of an ash layer may be ephemeral, as it often is quickly removed or redistributed by water and wind erosion, animals or traffic (Zavala et al., 2009a). Many authors have observed that the capacity of ash to protect soil depends on properties as the topography, the meteorological conditions and the thickness of ash coverage (Cerdà and Doerr, 2008; Pereira et al., 2013; Woods and Balfour, 2010; Zavala et al., 2009). Taking this into account, in this study we hypothesized that the wettability / hydrophobicity of the ash layer may have a significant effect on the soil response to splash erosion. Therefore, the aim of this study is to evaluate the dispersion of sediments produced by the impact of raindrops in function of ash wettability after a prescribed fire at plot scale. 2. MATERIAL AND METHODS In 20 November 2012, a prescribed fire was carried out in an area located in the public mount "Las Navas", near Almaden de la Plata, Sevilla (approx. 37° 50' 44.44'' N / 6° 3' 7.44''W and 428 masl). Soils are acidic and shallow, developed from acidic metamorphic rocks (schists, slates and pyrophyllites). Vegetation is dominated by shrub legumes (Calicotome villosa and several species of Ulex and Genista). The experimental area was framed and plowed to eliminate the risk of fire spreading during the experiment. Previously to burn, level staffs were installed for determination of flame height. The temperature reached in the soil was monitored during the fire by a set of six thermocouples which were buried in soil (2 cm depth) and connected to a data-logger for monitoring the topsoil temperature every 60 s. The environmental conditions were also monitored during the experiment by a mobile weather station. At the moment of the ignition, the temperature was around 20 °C and the wind speed was near 0.0 m/s. After ignition, the experimental area was allowed to burn during 2.5 h. During burning, flames reached 200 cm height, although thermal peaks recorded 2 cm depth were relatively low (not surpassing 80 °C). After burning, the soil surface was covered by a pattern of white and black ash, indicating varying degrees of fire severity, and areas covered by water repellent or hydrophilic ash were selected using the ethanol percentage test (EPT). The EPT provides an indirect measurement of the surface tension of the ground and, therefore, indicates the intensity of soil water repellency and is based on the different surface tension of a number of standardized solutions of ethanol in water. The procedure consists in applying drops (0.05 mL) of different ethanol solutions with different concentrations onto the surface of the ash layer observing if infiltration occurs in a period that not exceed 5 s (Jordán et al., 2010) . Every drop is allowed to fall from a distance not bigger than 15 mm to avoid the excess of kinetic energy that can affect infiltration. Applying drops with decreasing surface tension (that is, with concentrations of increasing ethanol) until a drop resists the infiltration allows the classification of the ground in a particular class of surface tension between two concentrations of ethanol: that in which infiltration occurs immediately (in less than 5 s) and the above solution of weaker concentration. Thus, it is assumed that solution whose drop is infiltrated within the first 5 s after application has a lower surface tension than soil surface. Fifteen representative points were selected at wettable or water-repellent ash zone. At each selected point, surrounded by white/wettable or dark/water-repellent ash to a minimum distance of 0.5 m, splash sediment collection device was installed. This system consist on a couple of funnels (100 mm in diameter) arranged one inside the other, with a paper filter beween both. Each device was inserted in soil until only 10 mm protruding the ground surface in order to avoid capturing runoff sediments. Sediments collected at each point of study were collected monthly and determined gravimetrically after oven drying between November 2012 and May 2013. 3. RESULTS AND DISCUSSION Depending on the intensity of the water repellency, the ash layer fluctuated between wettable and very strongly water repellent. The ash has a high permeability and water storage. However, its hydrophilic character has been emphasized rarely (Cerdà and Doerr, 2008). Different authors have described hydrophobic behaviors depending on the burned vegetation such as oak (Gabet and Sternberg, 2008) or pine forest (Stark, 1977) in the United States, eucalyptus forest in Australia (Khanna et al., 1996 ) or Mediterranean tree and shrub species in Spain (Bodí et al., 2011). In the latter case, Bodí et al. (2011) observed that ash has different properties depending on the combustion conditions, organic carbon content and color. This variability of behavior agrees with the results obtained in the present work. Significant differences between splash erosion from wettable and water-repellent ash zones were found (p < 0.0001). In the water-repellent ash zone, large differences were found among samples. The amount of sediment displaced by splash increased rapidly up to 264.10% (from 3.90 ± 0.44 to 14.20 ± 1.75 g) during the first four months after burn (November 2012 - February 2013). In contrast, during the last three months (March - May 2013), the amount of displaced sediments remained high, but with low growing rate (28.11%, from 16.97 ± 1.66 to 21.74 ± 3.27 g). In the wettable ash zone, the amount of sediment displaced was much smaller, with mean values between 1.29 (November 2012) and 6.14 g (May 2013). During the first two sampling dates after burn, data did not differ significantly among sites (1.38 ± 0.18 g on average), but the amount of sediment collected grew slowly during the experimental period between 3.06 ± 0.39 and 6.14 ± 0.69 g (January - May 2013). Several authors have suggested that ash acts protecting soil from the direct impact of raindrops and thus reduce sediment dispersion by splash (Cerdà and Doerr, 2008, Larsen et al, 2009; Woods and Balfour, 2008, Zavala et al, 2009). However, there is very little information about the effect of hydrophobicity on splash erosion. In a rainfall simulation experiment under laboratory conditions, Bodí et al. (2012) observed that splash erosion was at least two times higher in samples of water repellent soil than in hydrophilic soil, but no differences in ash loss or thickness of ash layer were observed. 4. CONCLUSIONS Our results highlight the role played by ash water repellency and the influence of burn severity on the development of a pattern of splash erosion intensities. Splash erosion was reduced in one order of magnitude on wettable ash zones. In contrast, the presence of a water-repellent ash layer increases the mobilization of sediments at plot scale. Further research should focus on the impacts of ash wettability on splash erosion at hillslope scale in the post fire. REFERENCES Bodí MB, Doerr SH, Cerdà A, Mataix-Solera J. 2012. Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma 191, 14-23. Bodí MB, Martin DA, Balfour VN, Santín C, Doerr SJ, Pereira P, Cerdà A. Mataix-Solera J. 2014. Wildland fire ash: Production, composition and eco-hydro-geomorphic effects. Earth-Sciece Reviews 130, 103-127. Cerdà A, Doerr, SH. 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena 74, 256-263. De Celis R, Jordán A, Zavala LM. 2013. Efectos del fuego en las propiedades biológicas, físicas y químicas del suelo. In: Bento-Gonçalves A, Vieira A (Eds.), Grandes incêndios florestais, erosão, degradação e medidas de recuperação dos solos. Núcleo de Investigação en Geografia e Planeamento (NIGP), Universidade do Minho. Guimaraes. Pp.: 145-160. DeBano LF. 1991. The effect of fire on soil. In: Harvey AE; Neuenschwander LF.(Eds.), Management and productivity of western-montane forest soils. General Technical Report INT-280. Intermountain Forest and Range Experimental Station, United States Department of Agriculture, Forest Service. Ogden, UT. DeBano LF. 2000. Water repellency in soils: a historical overview. Journal of Hydrology 231-232, 4-32. Doerr SH, Shakesby RA, Walsh RPD. 2000. Soil water repellency: its causes, characteristics and hydro-geomorphological significance. Earth-Science Reviews 51, 33-65. Larsen I, MacDonald LH, Brown E, Rough D, Welsh MJ, Pietraszek JH, Libohava Z, Benavides-Solorio JD, Schaffrath K. 2009. Causes of post-fire runoff and erosion: water repellency, cover or soil heating?. Soil Science Society of America Journal 73, 1393-1407. Mataix-Solera J, Guerrero C. 2007. Efecto de los incendios forestales sobre las propiedades edáficas. In: J. Mataix-Solera (Ed.) Incendios Forestales, Suelos y Erosión Hídrica. Caja Mediterráneo CENACAM Font Roja-Alcoi. Alicante. Pp.: 5-40. Mataix-Solera J, Guerrero C, Arcenegui V, Bárcenas G, Zornoza R, Pérez-Bejarano A, Bodí MB, Mataix-Beneyto J, Gómez I, García-Orenes F, Navarro-Pedreño J, Jordán MM, Cerdà A, Doerr SH, Úbeda X, Outeiro L, Jordán A, Zavala LM. 2009. Los incendios forestales y el suelo: un resumen de la investigación realizada por el Grupo de Edafología Ambiental de la UMH en colaboración con otros grupos. In: Cerdà A, Mataix-Solera J. (Eds.). El efecto de los incendios forestales sobre los suelos en España. El estado de la cuestión visto por los científicos españoles. Universitat de Valencia. Valencia. Pp.: 185-218. Mataix-Solera J, Cerdà A, Arcenegui V, Jordán A, Zavala LM. 2011. Fire efects on soil aggregation: a review. Earth-Science Reviews 109, 44-60 Neary DG, Klopatek CC, DeBano LF, Ffolliott PF. 1999. Fire effects on belowground sustainability: a review and synthesis. Forest Ecology and Management 122, 51-71. Pausas JG, Verdú M. 2005. Plant persistence traits in fire-prone ecosystems of the Mediterranean Basin: a phylogenetic approach. Oikos 109, 196-202. Pereira P, Úbeda X, Outeiro L, Martin D. 2009. Factor analysis applied to fire temperature effects on water quality. In: Gómez E, Álvarez K (Eds.), Forest Fires: Detection, Suppression and Prevention. Series Natural Disaster Research, Prediction and Mitigation, Nova Science Publishers, New York, NY. Pp.: 273-285 Pereira P, Cerdà A, Úbeda X, Mataix-Solera J, Martin D, Jordán A, Burguet M. 2013. Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania. Solid Earth 4, 153-165. Sevink J, Imeson AC, Verstraten JM. 1989. Humus form development and hillslope runoff, and the effects of fire and management, under Mediterranean forest in N.E. Spain. Catena 16, 461-475. Stark NM, 1977. Fire and nutrient cycling in a Douglas-fir/larch forest. Ecology, 58, 16-30. Trabaud L. 2000. Post-fire regeneration of Pinus halepensis forest in the west Mediterranean. In: Ne'eman G, Trabaud L (Eds.), Ecology, biogeography and management of Pinus halepensis and P. brutia forest ecosystems in the Mediterranean basin. Backhuys Publishers. Leiden. Pp.: 257-268. Woods SW, Balfour VN. 2008. Vegetative ash: an important factor in the short term response to rainfall in the post-fire environment. Geophysical Research Abstracts 10, EGU2008-A-00556. Woods SW, Balfour VN. 2010. The effects of soil texture and ash thickness on the post-fire hydrological response from ash-covered soils. Journal of Hydrology 393, 274-286. Zavala LM, Jordán A, Gil J, Bellinfante N, Pain C. 2009. Intact ash and charred litter reduces susceptibility to rain splash erosion post-wildfire Earth Surface Processes and Landforms, 34, 1522-1532. Zavala LM, De Celis R, Jordán A. 2014. How wildfires affect soil properties. A brief review Cuadernos de Investigación Geográfica 40, 311-331. AKNOWLEDGEMENTS This research is part of the POSTFIRE Project (ref. CGL2013-47862-C2-1-R), funded by the Spanish Ministry of Economy and Competitiveness. The authors are also grateful to the Environmental Management Centre (Mykolas Romeris University, Lithuania) and the Michoacan University (Morelia, Mexico) for their support.

Ash after forest fires. Effects on soil hydrology and erosion

NASA Astrophysics Data System (ADS)

Bodí, Merche B.

2013-04-01

Hillslopes were though to be most susceptible to enhanced hydro-geomorphological responses immediately following burning, with susceptibility declining during the first months or years depending on the soil and vegetation recovery. However, Cerdà (1998) found some indices in that immediately after the fire, the thin wettable ash layer that typically covers the ground could absorb rainfall and prevent or delay the onset of overland flow and associated erosion. Therefore the time lag while ash remains on the ground become of crucial importance to protect the soil after a wildfire. The effect of this ash layer was rarely been considered in detail because ash has often been reduced or redistributed by wind or water erosion before the onset of monitoring and thus the data collection typically begun some weeks or month after the fire. The first papers focussed only on ash and its hydrological effects were published by Cerdà and Doerr (2008) and by Woods and Balfour (2008). The results showed that the soil covered with ash indeed reduced and delayed surface runoff, reduced soil splash detachment and produced lower sediment yield compared to bare terrain. However, these findings arose more questions, as for instance: Why in other research there were indices that ash reduces infiltration? what is the mechanism by which why ash reduces overland flow? The research went further with Bodí PhD. First of all, it was crucial the agreement on the fact that the material "ash" is very variable depending on the original vegetation and the type and temperature of combustion. Therefore ash properties are different between wildfires even and within a fire. This is the main reason of its different effects and thus ash not always reduces runoff and sediment yield. In this way, depending on the nature of ash, it can increase overland flow if it is crusted (usually it contains a high content of calcium carbonate), it is water repellent (with high contents of organic carbon and specially from certain Eucaliptus and Pinus), or if clog soil pores (depending also on the soil type). If ash is wettable, it can store even 80% of its volume and then it will delay and reduce overland flow proportionally to the thickness of the ash layer. Once ash gets saturated, the flow tends to adjust to an infiltration rate similar to the soil itself, or sometimes higher due to the protection of ash that can reduce soil water repellency and soil sealing (Bodí et al. 2011, 2012). Still, many other aspects on ash remain unknown and ash present us more questions like, what it is its role on the carbon cycle? what is the extent of the ahs effects at basin scale? what is the fate of ash and how long it remains in the ecosystem? are there specific effects of ash depending on the ecosystem and so the type of ash? Acknowledgements This work was supported financially by a research fellowship (AP2007-04602) from the Spanish Ministry of Science and Innovation (M.B. Bodí) and the projects PT2009-0073 and CGL2010-21670-C02-01. References Bodí, M.B., Mataix-Solera, J., Doerr, S.H., Cerdà, A., 2011, The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma 160, 599-607. Bodí, M.B., Doerr, S.H., Cerdà, A., Mataix-Solera, J., 2012, Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma 191, 14-23 Cerdà, A., 1998, Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes 12, 1031-1042. Cerdà, A., Doerr, S.H., 2008, The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena 74, 256-263. Woods, S.W., Balfour, V., 2008, The effect of ash on runoff and erosion after a forest wildfire, Montana, U.S.A. International Journal of Wildland Fire 17, 535-548.

Wildfire Ash: Chemical Composition, Ash-Soil Interactions and Environmental Impacts

NASA Astrophysics Data System (ADS)

Brook, Anna; Hamzi, Seham; Wittenberg, Lea

2015-04-01

Of the five classical factors of soil formation, climate, parent material, topography, time, organisms, and recently recognized human activity, it is the latter factor which discretely includes fire and post-burn impact. However, it is considered that soil undergoing fire just experience a temporary removal of the top organic horizon, thus slightly modified and often labeled as 'temporarily disturbed' soil or soil 'under restoration/rehabilitation'. In fact the suggested seventh factor, post-burned produced ash, can act both dependently and independently of the other soil forming factors (Levin et al., 2013; Certini 2013). They are interdependent in cases where ash influences occur on time scales similar to 'natural' soil formation (Keesstra et ai., 2014) such as changes in vegetation. On the other hand, in post-fire areas a strong dependency is expected between soil-water retention mechanism, climate and topography. Wild-land fires exert many changes on the physical, chemical, mineralogical, biological, and morphological properties of soil that, in turn, affect the soil's hydrology and nutrient flux, modifying its ability to support vegetation and resist erosion. The ash produced by forest fires is a complex mixture composed of organic and inorganic particles characterized by vary physical-chemical and morphological properties. The importance of this study is straightforwardly related to the frequency and large-scales wildfires in Mediterranean region. In fact, wildfires are major environmental and land management concern in the world, where the number and severity of wildfires has increased during the past decades (Bodi, 2013). Certini (2013) assumed that cumulatively all of the vegetated land is burned in about 31 years annually affecting 330-430 Mha (over 3% of the Earth's surface) and wide range of land cover types worldwide including forests, peatlands, shrublands and grasslands. Whereas, the fire is identified as an important factor in soil formation, the produced ash has significant and not always constructive pedological, ecological, hydrological and geomorphological effects and impacts (Shakesby, 2011). Abundant scientific information is assembled either from control fires by collecting samples before and after wildfire event, or conducting laboratory experiments exanimating data under truly isolated conditions (Lugassi et al., 2013). However, an integration and synthesis of the knowledge about ash including deeper understanding of inter-correlation between chemical, physical and morphological compounds in open post-burn environment and its possible interactions in soil formation or impact on soil composition are highly needed. The main aim of the presented study was to advance the science of soil-fire relationship by recognizing the remains ash as a new soil-forming factor, on par with the traditionally recognized factors: parent material, topography, time, climate, organisms, and recently recognized human activity as the sixth factor. This research was conducted to develop new methods to assess impacts and quantify the contributions/influences of post-fire products, mainly ash, on soil composition and soil properties in post-burned environment. We conducted several controlled experiments using 40 soil samples (typical Mediterranean Rendzina soil, pH 6.84, a grayish-brown, humus- and free calcium carbonate- rich, intra-zonal). The samples include bare soils and different types and loads of forest litter, were exposed to different temperatures (200° C, 400° C and 600° C) in a muffle furnace for 2 hours (Pereira et al. 2011) as fire temperature plays a key role in determining ash properties. The ash produced at a low temperatures (50% carbon and retains many of the structural characteristics of the parent material. At higher temperatures, the residue ash is greyish, consisted of very fine particles that preserve almost none of the original structural characteristics of the fuel (Woods and Balfour, 2008) creating gradient of layered ash with diverse physicochemical properties. The obtained post-burned soils were processed as following: 1. loss of mass (ML); 2. ash layers sampling - the produced ash layers were collected separately; 3. grinding; 4. color - the Munsell colour chart; 5. spectroscopy- each sample was analysed by two spectrometer, first is the Ocean Optics USB4000 (0.35-1.05 μm) portable system across visible and near infrared (VNIR) region using contact Halogen illumination, second is the Bruker Tensor II (2.35-25 μm) across mid infrared (MIR) region by Furrier transform IR (FTIR) system using the Pike EasiDiff diffuse reflectance spectroscopy (DRS) optical bench; 6. pH and electrical conductivity (EC) including total dissolve solids (TDS) and salinity (S) measurements. The result of high concentration of carbonates, oxides, and hydroxides of basic cations decreasing EC levels caused by high pH (>8) there the CaCO3 surfaces are negatively charged and variation of mineralogical composition introducing very detailed list of minerals (high concentration of Nickeline NiAs, Cuprite Cu2O, Rehodochrosite MnCO3 and Nitrolite Na2Al2Si3O102H2O in the top-layers and mixtures e.g. Kaolinite/Smectite (85% Kaol.) Al2Si2O5(OH)4+(Na,Ca)0.33(Al,Mg)2Si4O10(OH)2nH2O and Mesolite + Hydroxyapophyllite Na2Ca2Al6Si9O308H2O + KCa4Si8O20(OH,F)8H2O between ash and post-burn top-soil layers. Bodí M.B., Muñoz-Santa I., Armero C., Doerr S.H., Mataix-Solera J., Cerdà A., 2013. Spatial and temporal variations of water repellency and probability of its occurrence in calcareous Mediterranean rangeland soils affected by fires. Catena, vol. 108, pp. 14-24. Certini G., Scalenghe R., Woods W.W., 2013. The impact of warfare on the soil environment. Earth-Science Reviews, vol. 127, pp. 1-15. Keesstra S.D., Temme A.J.A.M., Schoorl J.M., Visser S.M., 2014. Evaluating the hydrological component of new catchment-scale sediment delivery model LAPSUS-D. Geomorphology, vol. 212, pp. 97-107. Levin N., Levental S., Morag H., 2013. The effect of wildfires on vegetation cover and dune activity in Australia's desert dunes: a multisensor analysis International Journal of Wildland Fire, vol. 21 (4), pp. 459-475. Lugassi R., Ben-Dor E., Eshel G., 2013. Reflectance spectroscopy of soils post-heating'Assessing thermal alterations in soil minerals. Geoderma, vol. 231, pp. 268-279. Pereira P., Úbeda X., Martin D., Mataix-Solera J., Guerrero C. 2011. Effects of a low prescribed fire in ash water soluble elements in a Cork Oak (Quercus suber) forest located in Northeast of Iberian Peninsula, Environmental Research, vol. 111(2), pp. 237-247. Shakesby R.A., 2011. Post-wildfire soil erosion in the Mediterranean: Review and future research directions Earth Science Reviews, vol. 105, pp. 71-100. Woods, S.W., Balfour, V.N. 2010. The effects of soil texture and ash thickness on the post-fire hydrological response from ash-covered soils, Journal of Hydrology, vol. 393, pp. 274-286.

The Characteristics of Peats and Co2 Emission Due to Fire in Industrial Plant Forests

NASA Astrophysics Data System (ADS)

Ratnaningsih, Ambar Tri; Rayahu Prasytaningsih, Sri

2017-12-01

Riau Province has a high threat to forest fire in peat soils, especially in industrial forest areas. The impact of fires will produce carbon (CO2) emissions in the atmosphere. The magnitude of carbon losses from the burning of peatlands can be estimated by knowing the characteristics of the fire peat and estimating CO2 emissions produced. The objectives of the study are to find out the characteristics of fire-burning peat, and to estimate carbon storage and CO2 emissions. The location of the research is in the area of industrial forest plantations located in Bengkalis Regency, Riau Province. The method used to measure peat carbon is the method of lost in ignation. The results showed that the research location has a peat depth of 600-800 cm which is considered very deep. The Peat fiber content ranges from 38 to 75, classified as hemic peat. The average bulk density was 0.253 gram cm-3 (0.087-0,896 gram cm-3). The soil ash content is 2.24% and the stored peat carbon stock with 8 meter peat thickness is 10723,69 ton ha-1. Forest fire was predicted to burn peat to a depth of 100 cm and produced CO2 emissions of 6,355,809 tons ha-1.

Assessing fire emissions from tropical savanna and forests of central Brazil

NASA Technical Reports Server (NTRS)

Riggan, Philip J.; Brass, James A.; Lockwood, Robert N.

1993-01-01

Wildfires in tropical forest and savanna are a strong source of trace gas and particulate emissions to the atmosphere, but estimates of the continental-scale impacts are limited by large uncertainties in the rates of fire occurrence and biomass combustion. Satellite-based remote sensing offers promise for characterizing fire physical properties and impacts on the environment, but currently available sensors saturate over high-radiance targets and provide only indications of regions and times at which fires are extensive and their areal rate of growing as recorded in ash layers. Here we describe an approach combining satellite- and aircraft-based remote sensing with in situ measurements of smoke to estimate emissions from central Brazil. These estimates will improve global accounting of radiation-absorbing gases and particulates that may be contributing to climate change and will provide strategic data for fire management.

Prediction and Mitigation of the Effects of Catastrophic Fire on Water Supplies: Science for Risk Reduction and Planning for Future Scenarios

NASA Astrophysics Data System (ADS)

Martin, D. A.; Tindall, J.

2008-12-01

Precipitation falling on forests and grasslands provides much of the water to communities across the United States. The U.S. Forest Service estimates that over 3,400 communities are served by water draining land under its jurisdiction alone. Much of this land is subject to wildland fires, which have been increasing in size and severity in the western United States in response to climatic forcing and increased ignitions from human sources. Runoff from burned landscapes can present a significant risk to municipal and agricultural water supplies from ash, sediment, contaminants from burned structures, and fire-fighting chemicals. Several municipalities, including Denver, Colorado, have experienced both short-term and long-term degradation of their water supplies in the aftermath of fires in watersheds upstream from drinking water reservoirs. Scientific efforts to predict and mitigate the effects of catastrophic fire on water supplies have focused on three areas. The first consists of data collection and carefully designed experiments to understand the change of the hydrologic behavior of burned watersheds in response to rain with different intensities, durations, and trajectories as the watersheds recover. Results from these studies are used to validate models that predict watershed response under different initial conditions constrained by remotely-sensed burn severity, topography, rainfall-intensity recurrence probabilities and other factors. These predictions are the basis for rehabilitation measures applied to the landscape to minimize post-fire runoff and erosion. Efforts are under way to incorporate the chemical effects of ash and fire-fighting compounds in decision-support tools. A second area of scientific focus is the characterization of the chemical and physical properties of ash from wildland fire, including ash from structures consumed by fire. The ash chemistry is correlated to remotely- sensed data, type of vegetation that burned, and the underlying geology. Ash affects the hydraulic properties and behavior of soils in burned watersheds while it still mantles the hillslopes, but it is easily delivered to water bodies by rain and wind as a flush of material that affects water chemistry and properties like turbidity and temperature. A third thrust is to identify watersheds that are critical to the function of municipal water supplies and infrastructure to determine their vulnerability to fire and post-fire effects. This information can be used to prioritize areas for fuel treatments or land management practices to minimize the probability of high severity fire and hence the effects of post-fire runoff. Scientific studies are providing crucial information about such topics as changes in soil erodibility, infiltration and runoff after fire, and the effects of vegetation recovery. Even in watersheds where land management actions are limited by topography or land use designation, such as wilderness areas, knowledge of the potential response of burned areas allows water providers to develop rapid-response and long-term plans based on scientific data and tools. Some climate change models are predicting hotter, drier temperatures in certain areas of the United States and a higher probability of larger, more severe wildfires. These predictions have a direct bearing on the potential risk of impairment of water supplies by post-fire runoff and erosion. In an era when water availability and quality are of utmost importance, careful scientific studies focused on the effects of wildland fire on water supplies will continue to inform public policy and decision making on topics of vulnerability and risk reduction.

Remobilisation of industrial lead depositions in ash during Australian wildfires.

PubMed

Wu, Liqin; Taylor, Mark Patrick; Handley, Heather K

2017-12-01

This study examined the recycling of lead (Pb) in ash from wildfires, its source and potential contribution to environmental contamination. Ash from wildfires was collected from four Australian sites following uncontrolled fires during 2012 to 2013 close to major urban populations in Sydney (New South Wales), Hobart (Tasmania) and Adelaide (South Australia). The samples were analysed for their total Pb concentration and Pb isotopic composition to determine the sources of Pb and the extent, if any, of industrial contamination and its recycling into the ecosystem. Median ash concentrations (23mg/kg) released from a wildfire close to Australia's largest city, Sydney, exceeded the median ash Pb concentrations from wildfires from the less populated locations of Hobart, Adelaide and NSW Central Coast. Lead isotopic compositions of Duffys Forest wildfire ash demonstrate that anthropogenic inputs from legacy leaded petrol depositions were the predominant source of contamination. Despite the cessation of leaded petrol use in Australia in 2002, historic petrol Pb deposits continue to be a substantial source of contamination in ash: petrol Pb contributed 35% of the Pb in the Woy Woy ash, 73% in Duffys Forest ash, 39% in Forcett ash and 5% in Cherryville ash. The remobilisation of legacy industrial Pb depositions by wildfires in ash results in it being a persistent and problematic contaminant in contemporary environmental systems because of its known toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

Ten Years of Post-Fire Vegetation Recovery following the 2007 Zaca Fire using Landsat Satellite Imagery

NASA Astrophysics Data System (ADS)

Hallett, J. K. E.; Miller, D.; Roberts, D. A.

2017-12-01

Forest fires play a key role in shaping eco-systems. The risk to vegetation depends on the fire regime, fuel conditions (age and amount), fire temperature, and physiological characteristics such as bark thickness and stem diameter. The 2007 Zaca Fire (24 kilometers NE of Buellton, Santa Barbara County, California) burned 826.4 km2 over the course of 2 months. In this study, we used a time series of Landsat 5 Thematic Mapper and Landsat 8 Operational Land Imager imagery, to evaluate plant burn severity and post fire recovery as defined into classes of above average recovery, normal recovery, and below average recovery. We spectrally unmixed the images into green vegetation (GV), non-photosynthetic vegetation (NPV), soil surface (SOIL), and ash with a spectral library developed using Constrained Reference Endmember Selection (CRES). We delineated the fire perimeter using the differenced Normalized Burn Ratio (dNBR) and evaluated changes in this index and the Normalized Difference Vegetation Index through time. The results showed an immediate decline in GV and NPV fractions, with a rise in soil and ash fractions directly following the fire, with a slow recovery in GV fraction and a loss of bare soil cover. The was a sharp increase in the ash fraction following the fire and gradual decrease in the year after. Most areas have recovered as of 2017, with prominent recovery in the center of the burn scar and reduced recovery in areas to the south. These results indicate how post-fire vegetation varies based on initial burn severity and pre-fire GV and NPV fractions.

Micromorphological characteristics of sandy forest soils recently impacted by wildfires in Russia

NASA Astrophysics Data System (ADS)

Maksimova, Ekaterina; Abakumov, Evgeny

2017-04-01

Two fire-affected soils were studied using micromorphological methods. The objective of the paper is to assess and compare fire effects on the micropedological organisation of soils in a forest-steppe zone of central Russia (Volga Basin, Togliatti city). Samples were collected in the green zone of Togliatti city. The results showed that both soils were rich in quartz and feldspar. Mica was highly present in soils affected by surface fires, while calcium carbonates were identified in the soils affected by crown fires. The type of plasma is humus-clay, but the soil assemblage is plasma-silt with a prevalence of silt. Angular and subangular grains are the most dominant soil particulates. No evidence of intensive weathering was detected. There was a decrease in the porosity of soils affected by fires as a consequence of soil pores filled with ash and charcoal.

Trace elements in stormflow, ash, and burned soil following the 2009 station fire in southern California

USGS Publications Warehouse

Burton, Carmen; Hoefen, Todd M.; Plumlee, Geoffrey S.; Baumberger, Katherine L.; Backlin, Adam R.; Gallegos, Elizabeth; Fisher, Robert N.

2016-01-01

Most research on the effects of wildfires on stream water quality has focused on suspended sediment and nutrients in streams and water bodies, and relatively little research has examined the effects of wildfires on trace elements. The purpose of this study was two-fold: 1) to determine the effect of the 2009 Station Fire in the Angeles National Forest northeast of Los Angeles, CA on trace element concentrations in streams, and 2) compare trace elements in post-fire stormflow water quality to criteria for aquatic life to determine if trace elements reached concentrations that can harm aquatic life. Pre-storm and stormflow water-quality samples were collected in streams located inside and outside of the burn area of the Station Fire. Ash and burned soil samples were collected from several locations within the perimeter of the Station Fire. Filtered concentrations of Fe, Mn, and Hg and total concentrations of most trace elements in storm samples were elevated as a result of the Station Fire. In contrast, filtered concentrations of Cu, Pb, Ni, and Se and total concentrations of Cu were elevated primarily due to storms and not the Station Fire. Total concentrations of Se and Zn were elevated as a result of both storms and the Station Fire. Suspended sediment in stormflows following the Station Fire was an important transport mechanism for trace elements. Cu, Pb, and Zn primarily originate from ash in the suspended sediment. Fe primarily originates from burned soil in the suspended sediment. As, Mn, and Ni originate from both ash and burned soil. Filtered concentrations of trace elements in stormwater samples affected by the Station Fire did not reach levels that were greater than criteria established for aquatic life. Total concentrations for Fe, Pb, Ni, and Zn were detected at concentrations above criteria established for aquatic life.

Trace Elements in Stormflow, Ash, and Burned Soil following the 2009 Station Fire in Southern California

PubMed Central

Burton, Carmen A.; Hoefen, Todd M.; Plumlee, Geoffrey S.; Baumberger, Katherine L.; Backlin, Adam R.; Gallegos, Elizabeth; Fisher, Robert N.

2016-01-01

Most research on the effects of wildfires on stream water quality has focused on suspended sediment and nutrients in streams and water bodies, and relatively little research has examined the effects of wildfires on trace elements. The purpose of this study was two-fold: 1) to determine the effect of the 2009 Station Fire in the Angeles National Forest northeast of Los Angeles, CA on trace element concentrations in streams, and 2) compare trace elements in post-fire stormflow water quality to criteria for aquatic life to determine if trace elements reached concentrations that can harm aquatic life. Pre-storm and stormflow water-quality samples were collected in streams located inside and outside of the burn area of the Station Fire. Ash and burned soil samples were collected from several locations within the perimeter of the Station Fire. Filtered concentrations of Fe, Mn, and Hg and total concentrations of most trace elements in storm samples were elevated as a result of the Station Fire. In contrast, filtered concentrations of Cu, Pb, Ni, and Se and total concentrations of Cu were elevated primarily due to storms and not the Station Fire. Total concentrations of Se and Zn were elevated as a result of both storms and the Station Fire. Suspended sediment in stormflows following the Station Fire was an important transport mechanism for trace elements. Cu, Pb, and Zn primarily originate from ash in the suspended sediment. Fe primarily originates from burned soil in the suspended sediment. As, Mn, and Ni originate from both ash and burned soil. Filtered concentrations of trace elements in stormwater samples affected by the Station Fire did not reach levels that were greater than criteria established for aquatic life. Total concentrations for Fe, Pb, Ni, and Zn were detected at concentrations above criteria established for aquatic life. PMID:27144270

Salvage logging in the montane ash eucalypt forests of the Central Highlands of Victoria and its potential impacts on biodiversity.

PubMed

Lindenmayer, D B; Ought, K

2006-08-01

The two major forms of disturbance in the montane ash eucalypt forests of the Central Highlands of Victoria (southeastern Australia) are clearfell logging and unplanned wildfires. Since the 1930s wildfire has been followed by intensive and extensive salvage-logging operations, which may proceed for many years after a wildfire has occurred. Although applied widely, the potential effects of salvage logging on native flora and fauna have been poorly studied. Our data indicate that the abundance of large trees with hollows is significantly reduced in forests subject to salvage harvesting. This has implications for thepersistence of an array of such cavity-using vertebrates as the endangered arboreal marsupial, Leadbeater's possum (Gymnobelidues leadbeateri). Salvage logging also reduces the prevalence of multiaged montane ash forests--places that typically support the highest diversity of arboreal marsupials and forest birds. Limited research has been conducted on the effects of salvage logging on plants; thus, we constructed hypotheses about potential impacts for further testing based on known responses to clearfell logging and key life history attributes. We predict many species, such as vegetatively resprouting tree ferns, will decline, as they do after clearfelling. We also suggest that seed regenerators, which typically regenerate well after fire or conventional clearfelling, will decline after salvage logging because the stimulation for germination (fire) takes place prior to mechanical disturbance (logging). Understoryplant communities in salvage-logged areas will be dominated by a smaller suite of species, and those that are wind dispersed, have viable soil-stored seed remaining after salvage logging, or have deep rhizomes are likely to be advantaged. We recommend the following improvements to salvage-logging policies that may better incorporate conservation needs in Victorian montane ash forests: (1) exemption of salvage logging from some areas (e.g., old-growth stands and places subject to only partial stand damage); (2) increased retention of biological legacies on burned areas through variations in the intensity of salvage logging; and (3) reduction in the levels of physical disturbance on salvage-logged areas, especially through limited seedbed preparation and mechanical disturbance.

Characterization of post-fire surface cover, soils, and burn severity at the Cerro Grande Fire, New Mexico, using hyperspectral and multispectral remote sensing

USGS Publications Warehouse

Kokaly, R.F.; Rockwell, B.W.; Haire, S.L.; King, T.V.V.

2007-01-01

Forest fires leave behind a changed ecosystem with a patchwork of surface cover that includes ash, charred organic matter, soils and soil minerals, and dead, damaged, and living vegetation. The distributions of these materials affect post-fire processes of erosion, nutrient cycling, and vegetation regrowth. We analyzed high spatial resolution (2.4??m pixel size) Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) data collected over the Cerro Grande fire, to map post-fire surface cover into 10 classes, including ash, soil minerals, scorched conifer trees, and green vegetation. The Cerro Grande fire occurred near Los Alamos, New Mexico, in May 2000. The AVIRIS data were collected September 3, 2000. The surface cover map revealed complex patterns of ash, iron oxide minerals, and clay minerals in areas of complete combustion. Scorched conifer trees, which retained dry needles heated by the fire but not fully combusted by the flames, were found to cover much of the post-fire landscape. These scorched trees were found in narrow zones at the edges of completely burned areas. A surface cover map was also made using Landsat Enhanced Thematic Mapper plus (ETM+) data, collected September 5, 2000, and a maximum likelihood, supervised classification. When compared to AVIRIS, the Landsat classification grossly overestimated cover by dry conifer and ash classes and severely underestimated soil and green vegetation cover. In a comparison of AVIRIS surface cover to the Burned Area Emergency Rehabilitation (BAER) map of burn severity, the BAER high burn severity areas did not capture the variable patterns of post-fire surface cover by ash, soil, and scorched conifer trees seen in the AVIRIS map. The BAER map, derived from air photos, also did not capture the distribution of scorched trees that were observed in the AVIRIS map. Similarly, the moderate severity class of Landsat-derived burn severity maps generated from the differenced Normalized Burn Ratio (dNBR) calculation had low agreement with the AVIRIS classes of scorched conifer trees. Burn severity and surface cover images were found to contain complementary information, with the dNBR map presenting an image of degree of change caused by fire and the AVIRIS-derived map showing specific surface cover resulting from fire.

Disturbance gradient shows logging affects plant functional groups more than fire.

PubMed

Blair, David P; McBurney, Lachlan M; Blanchard, Wade; Banks, Sam C; Lindenmayer, David B

2016-10-01

Understanding the impacts of natural and human disturbances on forest biota is critical for improving forest management. Many studies have examined the separate impacts on fauna and flora of wildfire, conventional logging, and salvage logging, but empirical comparisons across a broad gradient of simultaneous disturbances are lacking. We quantified species richness and frequency of occurrence of vascular plants, and functional group responses, across a gradient of disturbances that occurred concurrently in 2009 in the mountain ash forests of southeastern Australia. Our study encompassed replicated sites in undisturbed forest (~70 yr post fire), forest burned at low severity, forest burned at high severity, unburned forest that was clearcut logged, and forest burned at high severity that was clearcut salvage logged post-fire. All sites were sampled 2 and 3 yr post fire. Mean species richness decreased across the disturbance gradient from 30.1 species/site on low-severity burned sites and 28.9 species/site on high-severity burned sites, to 25.1 species/site on clearcut sites and 21.7 species/site on salvage logged sites. Low-severity burned sites were significantly more species-rich than clearcut sites and salvage logged sites; high-severity burned sites supported greater species richness than salvage logged sites. Specific traits influenced species' sensitivity to disturbance. Resprouting species dominated undisturbed mountain ash forests, but declined significantly across the gradient. Fern and midstory trees decreased significantly in frequency of occurrence across the gradient. Ferns (excluding bracken) decreased from 34% of plants in undisturbed forest to 3% on salvage logged sites. High-severity burned sites supported a greater frequency of occurrence and species richness of midstory trees compared to clearcut and salvage logged sites. Salvage logging supported fewer midstory trees than any other disturbance category, and were distinctly different from clearcut sites. Plant life form groups, including midstory trees, shrubs, and ferns, were dominated by very few species on logged sites. The differences in biotic response across the gradient of natural and human disturbances have significant management implications, particularly the need to reduce mechanical disturbance overall and to leave specific areas with no mechanical disturbance across the cut area during logging operations, to ensure the persistence of resprouting taxa. © 2016 by the Ecological Society of America.

Transformation of goethite/ferrihydrite to hematite and maghemite under temperate humid conditions in Denmark

NASA Astrophysics Data System (ADS)

Nørnberg, P.; Finster, K.; Gunnlaugsson, H. P.; Jensen, S. K.; Merrison, J. P.; Vendelboe, A. L.

2012-04-01

At a number of sandy soil sites in Mid Jutland, Denmark, with iron content of 1-2%, very red spots (Munsell colour: dusky red 10R 3/4) of a few square meters are found. These spots are most likely due to burning events. After the fire ashes raised pH. This dispersed silt and clay size soil particles which were then transported with seepage water down into lower soil horizons. These particles contain hematite and maghemite due to influence of the fire. However, a long-standing unresolved question is how hematite and maghemite can also be present along with goethite and ferrihydrite, in the same geographical region, and in extended areas with high iron content (8-40 %) in the topsoil. Hematite and particularly maghemite would normally not be expected to form under the temperate humid Danish climate, but be interpreted as the result of high temperature as found in tropical regions or as seen in soils exposed to fire. The high iron content most likely has its origin in pyrite dissolution in top of the groundwater zone in deeper Miocene deposits. From there Fe2+ is brought to the surface by the groundwater, and in wells oxidized by meeting the atmosphere and precipitated as two line ferrihydrite. This is later transformed into goethite. However, along with these two minerals hematite and maghemite are present in the topsoil around the well area. Forest fires would be a likely explanation to the hematite and maghemite. But a body of evidence argues against these sites having been exposed to fire. 1) The pH in the topsoil is 3.6 - 4.8 and thus not raised by ashes. 2) No charcoal is present. 3) There is no indication of fire outside the high iron content areas. 4) Goethite is present along with hematite and maghemite in microparticles, and the mineralogical zonation produced in a forest fire is not seen. The natural sites contain a uniform mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. An experimental forest fire left charcoal and ashes at the topsoil, produced high pH, mineral zonation and decreased organic matter content, all of which is in contrast to the natural sites. In the freshly precipitated iron materials iron oxidizers as Gallionella sp. were found, but also iron reducing Geobachter sp.were present. Microbial activity might have influenced the mineral transformations.

Bispectral infrared forest fire detection and analysis using classification techniques

NASA Astrophysics Data System (ADS)

Aranda, Jose M.; Melendez, Juan; de Castro, Antonio J.; Lopez, Fernando

2004-01-01

Infrared cameras are well established as a useful tool for fire detection, but their use for quantitative forest fire measurements faces difficulties, due to the complex spatial and spectral structure of fires. In this work it is shown that some of these difficulties can be overcome by applying classification techniques, a standard tool for the analysis of satellite multispectral images, to bi-spectral images of fires. Images were acquired by two cameras that operate in the medium infrared (MIR) and thermal infrared (TIR) bands. They provide simultaneous and co-registered images, calibrated in brightness temperatures. The MIR-TIR scatterplot of these images can be used to classify the scene into different fire regions (background, ashes, and several ember and flame regions). It is shown that classification makes possible to obtain quantitative measurements of physical fire parameters like rate of spread, embers temperature, and radiated power in the MIR and TIR bands. An estimation of total radiated power and heat release per unit area is also made and compared with values derived from heat of combustion and fuel consumption.

Effects of fire on ash thickness in a Lithuanian grassland and short-term spatio-temporal changes

NASA Astrophysics Data System (ADS)

Pereira, P.; Cerdà, A.; Úbeda, X.; Mataix-Solera, J.; Martin, D.; Jordán, A.; Burguet, M.

2012-12-01

Ash thickness is a key variable in the protection of soil against erosion agents after planned and unplanned fires. Thicker ash provides better protection against raindrop impact and reduces the runoff response by retaining water and promoting water infiltration although little is known about the distribution and the evolution of the ash layer after the fires. Ash thickness measurements were conducted along two transects (flat and sloping areas) following a a grid experimental design. Both transects extended from the burned area into an adjacent unburned area. We analysed ash thickness evolution according to time and fire severity. In order to interpolate data with accuracy and identify the techniques with the least bias, several interpolation methods were tested in the grid plot. Overall, the fire had a low severity. The fire significantly reduced the ground cover, especially on sloping areas owing to the higher fire severity and/or less biomass previous to the fire. Ash thickness depends on fire severity and is thin where fire severity was higher and thicker in lower fire severity sites. The ash thickness decreased with time after the fire. Between 4 and 16 days after the fire, ash was transported by wind. The major reduction took place between 16 and 34 days after the fire as a result of rainfall, and was more efficient where fire severity was higher. Between 34 and 45 days after the fire no significant differences in ash thickness were identified among ash colours and only traces of the ash layer remained. The omni-directional experimental variograms shown that variable structure did not change importantly with the time, however, the most accurate interpolation methods were different highlighting the slight different patterns of ash thickness distribution with the time. The ash spatial variability increased with the time, particularly on the slope, as a result of water erosion.

Designing laboratory rainfall simulation experiments to examine the effects of a layer of vegetative ash on soil hydrology in Mediterranean areas

NASA Astrophysics Data System (ADS)

Bodí, Merche B.; Cerdà, Artemi; Doerr, Stefan H.; Mataix-Solera, Jorge

2010-05-01

Vegetative ash formed during forest wildfires often blankets the ground. Some studies have found the ash layer to increases infiltration by storing rainfall and protecting the underlying soil from sealing (Cerdà, and Doerr, 2008; Woods and Balfour, 2008), but at the same time, others identified it as a potential cause of increased overland flow due to sealing the soil pores or crusting (Mallik et al., 1984; Onda et al., 2008). The variability in the effects of ash depends mainly on the ash type and temperature of combustion, ash thickness and soil type (Kinner and Moody, 2007; Larsen et al., 2009). In order to study the effect of the ash layer on the soil hydrology and soil erosion under i) intense thunderstorms, ii) wettable and water repellent soil and iii) different ash thicknesses, rainfall simulation experiments were performed in a small plot (0.09 m2) in order to reach the highest accuracy. The simulator comprises a constant head tank of 40x40 cm with 190 hypodermic needles of 0.5 mm. A randomization screen served to break up the raindrops and ensure random drop landing positions (Kamphorst, 1987). The average of the intensities applied in the experiment was 82.5 ± 4.13 mm h-1 during 40 minutes. In order to verify the constancy of the intensity it was measured before and after each simulation. The rainfall was conducted in a metal box of 30x30 cm within 1 m of distance from the randomization screen. The slope of the box was set at 10° (17%). It is designed to collect overland flow and subsurface flow through the soil. Each rainfall simulation was conducted on 3 cm of both wettable and water repellent soil (WDPT>7200s). They are the same soil but one transformed into hydrophobic. The treatments carried out are: a) bare soil, b) 5 mm of ash depth, c) 15 mm of ash depth and d) 30 mm of ash depth, with three replicates. The ash was collected from a wildfire and the thicknesses are in the range of the reported in the literature. The first replicate was used for analysis of water repellency, infiltration pattern and ash incorporation into the soil and the other replicates are used for a second rainfall, one after 24 hours and the other after being dried 4 days in the oven at 25°C. In total there were 40 simulations. Overland flow and subsurface drainage were collected at 1-minute intervals and the forms was stored every 5 min to allow determination of sediment concentrations, yield and erosion rates. The experiment was completed with the installation of two moisture sensors at 1.5 cm of the soil and four splash cups that allowed determining the splash detachment at the end on the simulation. The importance in this series of experiments is the reproducibility and comparison of the different thicknesses of ash with the wettable and repellent soil. The results demonstrate that ash is a key factor on the post-fire soil erosion and hydrology and that rainfall simulation is a key tool to improve knowledge on low frequency - high magnitude events. References Cerdà, A. and Doerr, S.H., 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74: 256-263. Kamphorst, A., 1987. A small rainfall simulator for the determination of soil erodibility. Neth J Agric Sci 35, pp. 407-415. Kinner, D.A. and Moody, J.A., 2007. Infiltration and runoff measurements on steep burned hillslope using a rainfall simulator with variable rain intensities, U.S. Department of the Interior U.S. Geological Survey. Larsen, I.J. et al., 2009. Causes of post-fire runoff and erosion: water repellency, cover, or soil sealing? Soil Science SOciety American Journal 73: 1393-1407. Mallik, A.U., Gimingham, C.H. and Rahman, A.A., 1984. Ecological effects of heater burning. I. Water infiltration, moisture retention and porosity of surface soil. Journal of Ecology, 72: 767-776. Onda, Y., Dietrich, W.E. and Booker, F., 2008. Evolution of overland flow after a severe forest fire, Point Reyes, California. Catena, 72: 13-20. Woods, S.W. and Balfour, V., 2008. The effect of ash on runoff and erosion after a forest wildfire, Montana, U.S.A. International Journal of Wildland Fire, 17(5): 535-548.

Concentration of heavy metals in ash produced from Lithuanian forests

NASA Astrophysics Data System (ADS)

Baltrenaite, Edita; Pereira, Paulo; Butkus, Donatas; Úbeda, Xavier

2010-05-01

Wood ash contains important amounts of heavy metals. This quantity depends on burned specie, temperature of exposition and heat duration time. Due the high mineralization imposed by the temperatures, ash is used as lime product in agriculture and forests. Also, after a forest fire large quantities of ash are produced and distributed in soil surface. This mineralized organic matter can induce important environmental problems, including soil toxicity provoked by heavy metals leachates from ash. There is an extensive literature about heavy metals contents on ash in different species. However, it recently highlighted that the same species placed in different environments can respond diversely to same temperatures. This question is of major importance because temperature effects on severity can be a function of the plant communities instead of specie characteristics. These findings add a higher degree of complexity in the understanding of temperature effects on ash composition and consequent availability of heavy metals. The aim of this study is to compare the ash chemical heavy metal composition, Cobalt (Co), Chromium (Cr), Cooper (Cu), Silver (Ag), Lead (Pb), Nickel (Ni), Manganese (Mn) and Zinc (Zn), from Pinus sylvestris and Betula pendula, collected in key and representative areas of Lithuanian forests, located in southern, coastal and central part. Samples were collected from alive trees, taken to laboratory and air dried. Subsequently were crushed and submitted to muffle furnace at temperature of 550°C during two hours. The ash samples were digested and in a HNO3-HCl solution and then analysed with AAS. Comparisons between species and sites were performed with a Non-parametric one-way ANOVA‘s on rank transformed data followed by Tukey‘s HSD, significant at a p<0.05. Results showed significant difference between Co and Ag concentrations between Pinus sylvestris and Betula pendula. Also, significantly different concentrations of Pb, Cu, Ni and Mn were determined among investigated sites. No significant difference was found for Zn and Cr among investigated sites. Variation of metals between sites and stands can be explained by their age, flammability difference between plant communities and anthropogenic heavy metal load. These and other aspects will be discussed with more detail in the communication.

Lightning in Colorado forest fire smoke plumes during summer 2012

NASA Astrophysics Data System (ADS)

Lang, T. J.; Krehbiel, P. R.; Dolan, B.; Lindsey, D.; Rutledge, S. A.; Rison, W.

2012-12-01

May and June 2012 were unusually hot and dry in Colorado, which was suffering from a strong drought. A major consequence of this climatic regime was one of the most destructive forest fire seasons in state history, with hundreds of thousands of acres of forest and grassland consumed by flames, hundreds of homes burned, and several lives lost. Many of these fires occurred within range of the newly installed Colorado Lightning Mapping Array (COLMA), which provides high-resolution observations of discharges over a large portion of the state. The COLMA was installed in advance of the Deep Convective Clouds and Chemistry (DC3) project. High-altitude lightning was observed to occur sporadically in the smoke plumes over three major fires that occurred during early summer: Hewlett Gulch, High Park, and Waldo Canyon. Additionally, the Colorado State University CHILL (CSU-CHILL) and Pawnee radars observed the Hewlett Gulch plume electrify with detailed polarimetric and dual-Doppler measurements, and also provided these same measurements for the High Park plume when it was not producing lightning. Meanwhile, local Next Generation Radars (NEXRADs) provided observations of the electrified High Park and Waldo Canyon plumes. All of these plumes also were observed by geostationary meteorological satellites. These observations provide an unprecedented dataset with which to study smoke plume and pyrocumulus electrification. The polarimetric data - low reflectivity, high differential reflectivity, low correlation coefficient, and noisy differential phase - were consistent with the smoke plumes and associated pyrocumulus being filled primarily with irregularly shaped ash particles. Lightning was not observed in the plumes until they reached over 10 km above mean sea level, which was an uncommon occurrence requiring explosive fire growth combined with increased meteorological instability and reduced wind shear. Plume updraft intensification and echo-top growth led the occurrence of lightning by 10-15 minutes. Discharges typically only occurred over the span of a few minutes thereafter, or sporadically over the course of one of more hours. Plume lightning was intra-cloud and relatively small in size, and featured extensive precursor activity. Due to the preponderance of ash in the plumes and the lack of precipitation-sized ice, electrification had to occur via some other mechanism besides standard graupel-based non-inductive mechanisms. Triboelectric charging of the ash particles, aided by reduced breakdown fields at high altitudes, is posited as the primary mechanism behind the lightning in these smoke plumes.

Old-growth definition for western juniper woodlands: Texas ashe juniper dominated or codominated communities. Forest Service general technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diamond, D.D.

1997-09-01

Ashe juniper dominated or codominated woodlands are extensive within the Edwards Plateu in Texas. Almost all contemporary woodlands are the result of various disturbances, especially grazing and fire suppression. Old-growth examples are rare. Several different geomorphic situations once supported natural Ashe juniper communities with different dynamics and composition. These included mesic slopes and canyon systems, shallow-soiled uplands (hardscrabble), and deeper-soiled uplants. The most extensive and most diverse woodlands were in canyon systems, where Ashe juniper shared dominance with a diversity of oaks and other broad-leaved trees, Drier upland woodlands were less diverse, with live oak, shin oak, and Vasey oakmore » variously important. Ashe junipr woodlands harbor a diverse biota, including rare and endemic species, and, thus, preservation of representative old-growth examples is an important conservation concern.« less

Fire-induced risk in Andisols: An State-of-the-Art

NASA Astrophysics Data System (ADS)

Neris, Jonay; Cerdà, Artemi; Santamarta, Juan C.; Doerr, Stefan

2014-05-01

Wildfires are increasingly recognized as the primary natural hazard affecting forests and woodlands (Pausas, 2004), and changing the soil properties due to the heat (Aznar et al., 2013). They are also the factor that determines the increase in soil and water losses (Cerdà, 1998a; Shakesby, 2011). Fire contributes to increase the surface runoff due to the water repellency (Mataix-Solera et al., 2004; Cerdà and Doerr, 2008) although a quick recovery is found when vegetation is recovered (Cerdà, 1988b; Guénon et al., 2013). Within the recovery process ash is the key factor once the vegetation is recovered (Bodí et al., 2011; León et al., 2013; Pereira et al., 2013). To reduce the impact of forest fires some strategies were developed (Prats et al., 2013). The fire direct and indirect impacts on ecosystems and the human population, infrastructures, supplies and goods have been increasing over the last decades due to climatic and socio-economic changes and are projected to increase further in the future. In the densely populated volcanic regions that are characterized by steep and fire-prone slopes, Andisols are the main soil type. Their mineralogical properties provide them with specific chemical and physical properties which strength their fertility and resistance to erosion but also differentiate their response to environmental disturbances such as land use change (Jiménez et al., 2006; Neris et al., 2012) but also forest fires and agricultural burning (Neris et al., 2013; Poulenard et al., 2001). Despite their relevance for human development and safety, little specific knowledge exists about them and papers addressing their singularities are limited. This works seeks to compile and review existing scientific works focused on the effects of fire on this particular type of soils, evaluate their response to this disturbance and identify knowledge gaps related to the fire-induced risk in Andisols in order to develop new lines of research. Acknowledgements This work has been developed in the framework of the RECLAND Project. It has been funded by the European Union under Lifelong Learning Programme, Erasmus Programme: Erasmus Multilateral Projects, 526746-LLP-1-2012-1-ES-ERASMUS-EMCR, MSc Programme in Climate Change and Restoration of Degraded Land. The research projects GL2008-02879/BTE, LEDDRA 243857 and RECARE FP7 project 603498 supported this research. References Aznar, J.M., González-Pérez, J.A., Badía, D., Martí, C. 2013. At what depth are the properties of a Gypseous forest topsoil affected by burning?. Land Degradation and Development, DOI: 10.1002/ldr.2258 Bodí, M., Mataix-Solera, J., Stefan H. Doerr, S.H., Cerdà, A. 2012. The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma 160, 599-607. Cerdà, A. 1998a. Postfire dynamics of erosional processes under mediterranean climatic conditions. Zeitschrift für Geomorphologie, 42 (3) 373-398. Cerdà, A. 1998b. Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes, 12, 1031-1042. Cerdà, A., Doerr, S.H. 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74 , 256- 263. doi:10.1016/S0341-8162(02)00027-9 Guénon, R., Vennetier, M., Dupuy, N., Roussos, S., Pailler, A., Gros, R. 2013. Trends in recovery of Mediterranean soil chemical properties and microbial activities after infrequent and frequent wildfires. Land Degradation & Development, 24: 115-128, DOI: 10.1002/ldr.1109. Jiménez, C., Tejedor, M., Morillas, G., Neris, J., 2006. Infiltration rate in Andisols: Effect of changes in vegetation cover (Tenerife, Spain). Journal of Soil and Water Conservation 61(3), 153-158. León, J., Bodí, M.B., Cerdà, A., Badía, D., 2013. The contrasted response of ash to wetting: The effects of ash type, thickness and rainfall events. Geoderma 209-210, 143-152. Mataix-Solera, J., Doerr, S.H. 2004. Hydrophobic and aggregate stability in calcareous topsoils from fire-affected pine forest in southeastern Spain. Geoderma 118, 77-88. Neris, J., Jiménez, C., Fuentes, J., Morillas, G., Tejedor, M., 2012. Vegetation and land-use effects on soil properties and water infiltration of Andisols in Tenerife (Canary Islands, Spain). Catena 98(0), 55-62. Neris, J., Tejedor, M., Fuentes, J., Jiménez, C., 2013. Infiltration, runoff and soil loss in Andisols affected by forest fire (Canary Islands, Spain). Hydrological Processes 27(19), 2814-2824. Pausas, J.G. 2004. Changes in fire and climate in the eastern Iberian Peninsula (Mediterranean basin). Climatic Change 63: 337-350. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Martin, D., Jordán, A., Burguet, M. 2013. Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania. Solid Earth, 4: 153-165. Poulenard, J., Podwojewski, P., Janeau, J.L., Collinet, J., 2001. Runoff and soil erosion under rainfall simulation of Andisols from the Ecuadorian Páramo: Effect of tillage and burning. Catena 45(3), 185-207. Prats, S.A., Malvar, M.C., Simões-Vieira, D.C., MacDonald, L., and Keizer, J.J. 2013. Effectiveness of hydromulching to reduce runoff and erosion in a recently burnt pine plantation in central Portugal. Land Degradation & Development, DOI: 10.1002/ldr.2236. Prats, S.A., Malvar, M.C., Simões-Vieira, D.C., MacDonald, L., and Keizer, J.J. 2013. Effectiveness of hydromulching to reduce runoff and erosion in a recently burnt pine plantation in central Portugal. Land Degradation & Development, DOI: 10.1002/ldr.2236. Shakesby, R.A. 2011. Post-wildfire soil erosion in the Mediterranean: Review and future research directions. Earth Science Reviews, 105, 71-100.

Characterization of polycyclic aromatic hydrocarbons and metals in ashes released from a forest fire

NASA Astrophysics Data System (ADS)

Campos, I.; Abrantes, N.; Pereira, P.; Vale, C.; Ferreira, A.; Keizer, J. J.

2012-04-01

Wildfires have become a permanent source of environmental and societal concerns. Whilst the impacts of wildfire on hydrological and erosion processes are well documented, the stocks and export of polycyclic aromatic hydrocarbons (PAHs) and heavy metals have received considerably less research attention. The ashes produced by wildfires, which include polluting substances such as PAHs and metals, are subject to transport processes by wind and especially by overland flow and water infiltrating into the soil and possibly reaching ground water bodies. In the framework of the FIRECNUTS project, we are studying the stocks of PAHs and selected metals in recently burnt forest stands in north-central Portugal, and their subsequent export by overland flow. The present work, however, will focus on the stocks in the ashes, both immediately after wildfire and three months later. These ashes were collected at two burnt slopes with contrasting forest types, i.e. a eucalypt and a maritime pine stand, the two pre-dominant forest types in the study region. The sixteen PAHs identified by US EPA as priority contaminants were analysed by gas chromatograph, after extraction and column clean up. The contents of vanadium (V), chromium (Cr), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) were analysed by inductively coupled plasma- mass spectrometry (ICP-MS), after an acid digestion, while mercury (Hg) was analysed by pyrolysis atomic absorption spectrometry with gold amalgamation. The total concentration of PAHs immediately after the wildfire ranged from 314 ng/g dry weight in the maritime pine stand to 597 ng/g dry weight in the eucalypt stand. Three months later, the total concentration has decreased with 33% in the pine stand but only half (16%) in the eucalypt stand. The composition the PAHs by ring size was dominated by three-rings PAHs. This was true for all samples. The concentrations of various metals differed for the two sampling occasions but not in straightforward manners. Some metals (Co, Ni, Cu, Zn, Cd, Pb and Hg) revealed higher contents immediately after the fire, whereas others (V, Cr and As) did three months later. The present results underline the importance of furthering the knowledge about contamination of soil and water by ashes from wildfires and the associated risks in terms of ecotoxicological effects, both in-situ and in downstream aquatic systems. Keywords: Polycyclic aromatic hydrocarbons (PAH); heavy metals; stocks; ash; wildfires

Predicting fire effects on water quality: a perspective and future needs

NASA Astrophysics Data System (ADS)

Smith, Hugh; Sheridan, Gary; Nyman, Petter; Langhans, Christoph; Noske, Philip; Lane, Patrick

2017-04-01

Forest environments are a globally significant source of drinking water. Fire presents a credible threat to the supply of high quality water in many forested regions. The post-fire risk to water supplies depends on storm event characteristics, vegetation cover and fire-related changes in soil infiltration and erodibility modulated by landscape position. The resulting magnitude of runoff generation, erosion and constituent flux to streams and reservoirs determines the severity of water quality impacts in combination with the physical and chemical composition of the entrained material. Research to date suggests that most post-fire water quality impacts are due to large increases in the supply of particulates (fine-grained sediment and ash) and particle-associated chemical constituents. The largest water quality impacts result from high magnitude erosion events, including debris flow processes, which typically occur in response to short duration, high intensity storm events during the recovery period. Most research to date focuses on impacts on water quality after fire. However, information on potential water quality impacts is required prior to fire events for risk planning. Moreover, changes in climate and forest management (e.g. prescribed burning) that affect fire regimes may alter water quality risks. Therefore, prediction requires spatial-temporal representation of fire and rainfall regimes coupled with information on fire-related changes to soil hydrologic parameters. Recent work has applied such an approach by combining a fire spread model with historic fire weather data in a Monte Carlo simulation to quantify probabilities associated with fire and storm events generating debris flows and fine sediment influx to a reservoir located in Victoria, Australia. Prediction of fire effects on water quality would benefit from further research in several areas. First, more work on regional-scale stochastic modelling of intersecting fire and storm events with landscape zones of erosion vulnerability is required to support quantitative evaluation of water quality risk and the effect of future changes in climate and land management. Second, we underscore previous calls for characterisation of landscape-scale domains to support regionalisation of parameter sets derived from empirical studies. Recent examples include work identifying aridity as a control of hydro-geomorphic response to fire and the use of spectral-based indices to predict spatial heterogeneity in ash loadings. Third, information on post-fire erosion from colluvial or alluvial stores is needed to determine their significance as both sediment-contaminant sinks and sources. Such sediment stores may require explicit spatial representation in risk models for some environments and sediment tracing can be used to determine their relative importance as secondary sources. Fourth, increased dating of sediment archives could provide regional datasets of fire-related erosion event frequency. Presently, the lack of such data hinders evaluation of risk models linking fire and storm events to erosion and water quality impacts.

Modelling the effect of wildfire on forested catchment water quality using the SWAT model

NASA Astrophysics Data System (ADS)

Yu, M.; Bishop, T.; van Ogtrop, F. F.; Bell, T.

2016-12-01

Wildfire removes the surface vegetation, releases ash, increase erosion and runoff, and therefore effects the hydrological cycle of a forested water catchment. It is important to understand chnage and how the catchment recovers. These processes are spatially sensitive and effected by interactions between fire severity and hillslope, soil type and surface vegetation conditions. Thus, a distributed hydrological modelling approach is required. In this study, the Soil and Water Analysis Tool (SWAT) is used to predict the effect of 2001/02 Sydney wild fire on catchment water quality. 10 years pre-fire data is used to create and calibrate the SWAT model. The calibrated model was then used to simulate the water quality for the 10 years post-fire period without fire effect. The simulated water quality data are compared with recorded water quality data provided by Sydney catchment authority. The mean change of flow, total suspended solid, total nitrate and total phosphate are compare on monthly, three month, six month and annual basis. Two control catchment and three burn catchment were analysed.

Effects of burn temperature on ash nutrient forms and availability from cattail (Typha domingensis) and sawgrass (Cladium jamaicense) in the Florida Everglades.

PubMed

Qian, Y; Miao, S L; Gu, B; Li, Y C

2009-01-01

Plant ash derived from fire plays an important role in nutrient balance and cycling in ecosystems. Factors that determine the composition and availability of ash nutrients include fire intensity (burn temperature and duration), plant species, habitat nutrient enrichment, and leaf type (live or dead leaf). We used laboratory simulation methods to evaluate temperature effects on nutrient composition and metals in the residual ash of sawgrass (Cladium jamaicense) and cattail (Typha domingensis), particularly on post-fire phosphorus (P) availability in plant ash. Live and dead leaf samples were collected from Water Conservation Area 2A in the northern Everglades along a soil P gradient, where prescribed fire may be used to accelerate recovery of this unique ecosystem. Significant decreases in total carbon and total nitrogen were detected with increasing fire temperature. Organic matter combustion was nearly complete at temperatures > or = 450 degrees C. HCl-extractable P (average, 50% of total P in the ash) and NH(4)Cl-extractable P (average, 33% of total P in the ash) were the predominant P fractions for laboratory-burned ash. Although a low-intensity fire could induce an elevation of P availability, an intense fire generally resulted in decreased water-soluble P. Significant differences in nutrient compositions were observed between species, habitat nutrient status, and leaf types. More labile inorganic P remained in sawgrass ash than in cattail ash; hence, sawgrass ash has a greater potential to release available P than cattail. Fire intensity affected plant ash nutrient composition, particularly P availability, and the effects varied with plant species and leaf type. Therefore, it is important to consider fire intensity and vegetation community when using a prescribed fire for ecosystem management.

Post Wildfire Changes in Plant Functioning and Vegetation Dynamics: Implications for Water Fluxes in Re-sprouting Forests

NASA Astrophysics Data System (ADS)

Nolan, R. H.; Lane, P. N.; Mitchell, P. J.; Bradstock, R. A.

2011-12-01

Fire induced changes to the vegetation dynamics in temperate forests have been demonstrated to affect evapotranspiration (Et) rates through increases in plant size and density and stand-level transpiration and interception. In many cases these transient changes in forest structure result in substantial declines in stream flow for protracted periods after the disturbance. However to date research has focused on the wetter 'ash' forests of south-eastern Australia which solely regenerate via seedlings, it is unknown what changes in Et may occur in those forests which re-sprout post-fire. We hypothesize that Et fluxes track post-fire changes in sapwood area and leaf area index (L) in re-sprouting temperate forests, increasing as the forest regenerates. Following the 2009 Black Saturday wildfires in Victoria, we monitored Et rates for over a year in both damp and dry re-sprouting forest, incorporating a range of fire severity classes. Components of Et including overstorey transpiration, rainfall interception loss and forest floor Et were measured in conjunction with changes in L, sapwood area and leaf physiology. The monitoring period began one year post-fire with a typical hot, dry summer, at which stage Et rates in burnt forest were similar or less than those in unburnt forest. During the following summer, which was one of the wettest on record, Et increased across all monitoring plots but particularly so in the burnt forest where seedling regeneration resulted in an understorey L nearly twice that of unburnt forest. Forest floor Et was up to 46% higher in burnt forest, and rainfall interception values accounted for approximately 25% of rainfall compared to 15% in unburnt forest. The greatest increase in canopy transpiration rates over this period occurred in those trees subject to a low intensity fire where most of the canopy remained intact but there was also fire-triggered sprouting of new leaves along the trunk and main branches. In these trees rates of sapflow, standardized by sapwood area, were up to 50% greater than in unburnt trees. Measurements of leaf physiology in mature leaves, regenerating canopy leaves and in seedlings indicate higher rates of stomatal conductance in seedlings, and in the early regeneration phase of canopy leaves, which may be driving higher rates of water use per unit leaf area in the early stages of post-fire regeneration. This research indicates that disturbance-induced changes in vegetation dynamics are dependent on fire severity and can alter forest energy and water balances through changes in stand structure (i.e. L) and adjustments in plant functioning via leaf level increases in water use.

Using synthetic polymers to reduce soil erosion after forest fires in Mediterranean soils

NASA Astrophysics Data System (ADS)

Lado, Marcos; Ben-Hur, Meni; Inbar, Assaf

2010-05-01

Forest fires are a major environmental problem in the Mediterranean region because they result in a loss of vegetation cover, changes in biodiversity, increases in greenhouse gasses emission and a potential increase of runoff and soil erosion. The large increases in runoff and sediment yields after high severity fires have been attributed to several factors, among them: increase in soil water repellency; soil sealing by detached particles and by ash particles, and the loss of a surface cover. The presence of a surface cover increases infiltration, and decreases runoff and erosion by several mechanisms which include: rainfall interception, plant evapotranspiration, preservation of soil structure by increasing soil organic matter, and increasing surface roughness. The loss of vegetation cover as a result of fire leaves the surface of the soil exposed to the direct impact of the raindrops, and therefore the sensitivity of the soil to runoff generation and soil loss increases. In this work, we propose a new method to protect soils against post-fire erosion based on the application of synthetic polymers to the soil. Laboratory rainfall simulations and field runoff plots were used to analyze the suitability of the application of synthetic polymers to reduce soil erosion and stabilize soil structure in Mediterranean soils. The combination of these two processes will potentially favor a faster recovery of the vegetation structure. This method has been successfully applied in arable land, however it has not been tested in burnt forests. The outcome of this study may provide important managerial tools for forest management following fires.

Spatial models to predict ash pH and Electrical Conductivity distribution after a grassland fire in Lithuania

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerda, Artemi; Misiūnė, Ieva

2015-04-01

Fire mineralizes the organic matter, increasing the pH level and the amount of dissolved ions (Pereira et al., 2014). The degree of mineralization depends among other factors on fire temperature, burned specie, moisture content, and contact time. The impact of wildland fires it is assessed using the fire severity, an index used in the absence of direct measures (e.g temperature), important to estimate the fire effects in the ecosystems. This impact is observed through the loss of soil organic matter, crown volume, twig diameter, ash colour, among others (Keeley et al., 2009). The effects of fire are highly variable, especially at short spatial scales (Pereira et al., in press), due the different fuel conditions (e.g. moisture, specie distribution, flammability, connectivity, arrangement, etc). This variability poses important challenges to identify the best spatial predictor and have the most accurate spatial visualization of the data. Considering this, the test of several interpolation methods it is assumed to be relevant to have the most reliable map. The aims of this work are I) study the ash pH and Electrical Conductivity (EC) after a grassland fire according to ash colour and II) test several interpolation methods in order to identify the best spatial predictor of pH and EC distribution. The study area is located near Vilnius at 54.42° N and 25.26°E and 154 ma.s.l. After the fire it was designed a plot with a 27 x 9 m space grid. Samples were taken every 3 meters for a total of 40 (Pereira et al., 2013). Ash color was classified according to Úbeda et al. (2009). Ash pH and EC laboratory analysis were carried out according to Pereira et al. (2014). Previous to data comparison and modelling, normality and homogeneity were assessed with the Shapiro-wilk and Levene test. pH data respected the normality and homogeneity, while EC only followed the Gaussian distribution and the homogeneity criteria after a logarithmic transformation. Data spatial correlation was calculated with the Global Moran's I Index. In order to identify the best interpolator, we tested several well known techniques as inverse distance to a power (IDP), with the power of 1, 2, 3, 4 and 5, local polynomial (LP) with the power of 1 (LP1), 2 (LP2) and 3 (LP3), spline with tension (SPT), completely regularized spline (CRS), multiquadratic (MTQ), inverse multiquadratic (IMTQ) thin plate spline (TPS) and ordinary kriging. The best interpolator was the one with the lowest Root mean square error (RMSE). The results shown that on average ash pH was 8.01 (±0.20) and EC (1408± 513.51µm cm3). The coefficient of correlation between both variables was 0.34, p<0.05. Black ash had a significantly higher pH (F=6.29, p<0.05) and EC (F=5.25, p<0.05) than dark grey ash. According to Moran's I index, pH data was significantly (p<0.05) dispersed, while EC had a random pattern. The best spatial predictor for pH was IDW1 (RMSE=0.210), and for EC IMTQ (RMSE=0.141). In both cases the least accurate technique was TPS. pH data did not showed a specific spatial pattern and some high values are very close to high values which shows a great local spatial variability, mainly observed in the northern part of the plot. In relation to EC, the high values were identified in the central part of the plot. In conclusion it was observed that ash pH and EC were different according to fire severity (ash color) and data distribution has a different spatial pattern, despite the significant correlation. pH and EC had different spatial impacts on soil properties in the immediate period after the fire. Acknowledgments POSTFIRE (Soil quality, erosion control and plant cover recovery under different post-fire management scenarios, CGL2013-47862-C2-1-R), funded by the Spanish Ministry of Economy and Competitiveness; Fuegored; RECARE (Preventing and Remediating Degradation of Soils in Europe Through Land Care, FP7-ENV-2013-TWO STAGE), funded by the European Commission; and for the COST action ES1306 (Connecting European connectivity research). References Keeley, J.E. (2009) Fire intensity, fire severity and burn severity: a brief review and suggested usage. International Journal of Wildland Fire. 18, 116-126. Pereira, P., Úbeda, X., Martin, D., Mataix-Solera, J., Cerdà, A., Burguet, M. (2014) Wildfire effects on extractable elements in ash from a Pinus pinaster forest in Portugal. Hydrological Processes, 28, 3681-3690. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. Modelling the impacts of wildfire on ash thickness in a short-term period. Land Degradation and Development, (In Press), DOI: 10.1002/ldr.2195 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Jordan, A. Burguet, M. (2013) Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania, Solid Earth, 4, 153-165. Úbeda, X., Pereira, P., Outeiro, L., Martin, D. (2009) Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of cork oak (Quercus suber). Land Degradation and Development, 20(6), 589-608.

Effects of a layer of vegetative ash layer on wettable and water repellent soil hydrology

NASA Astrophysics Data System (ADS)

Bodí, Merche B.; Doerr, Stefan H.; Cerdà, Artemi; Mataix-Solera, Jorge

2010-05-01

Following a wildfire, a layer of vegetative ash often covers the ground until it is dissolved or redistributed by wind and water erosion. Much of the existing literature suggests that the ash layer temporally reduces infiltration by clogging soil pores or by forming a surface crust (Mallik et al., 1984; Onda et al., 2008). However, an increasing number of field-based studies have found that, at least in the short term, ash increases infiltration by storing rainfall and protecting the underlying soil from sealing (Cerdà and Doerr, 2008; Woods and Balfour, 2008). On the other hand, after a fire the soil may have produced, enhanced or reduced its water repellency (Doerr et al., 2000). Very few studies have been taken into account the interaction of the ash and the repellent soil. The layer of ash may have similar role as a litter layer in delaying runoff and reducing erosion by storing water. In order to examine this interaction, it was been made a series of experiments using a laboratory rainfall simulation. It has been assessed the effects of an ash layer i) on a wettable and water repellent soil (WDPT > 7200s), ii) with different ash thicknesses (bare soil and 5 mm, 15 mm and 30 mm of ash), iii) preceding and following the first rain after a fire when the ground is still wetted and after being partially dried. Three replicates were done, being a total of 40 simulations. The ash used was collected from a Wildfire in Teruel (Spain) during summer of 2009. The simulations were conducted in metal boxes of 30x30 cm and filled with 3 cm of soil. The slope of the box was set at 10° (17%) and the intensity applied was 78-84 mm h-1during 40 minutes. The splash detachment was determined also using four splash cups. Overland flow and subsurface drainage was collected at 1-minute intervals and the former stored every 5 min to allow determination of sediment concentrations, yield and erosion rates. Each sample was examined at the end in terms of water repellency, infiltration pattern and ash incorporation into the soil. The results show that when ash covers the wettable soil, runoff occur for a short period of time in the middle of the event. It occurred latter on time but larger in quantity as the ash thickness increases (from 0% to 2% of runoff coefficient) and at the same time drainage is reduced (from 57 to 24%). This suggests that the ash layer became saturated and produce runoff until the water is able to drain into the soil. Oppositely, in water repellent soil as ash thickness increases both runoff is reduced (from 78% to 26%) and drainage is increased (from 0 to 16%). That fact indicates a modification in the hydraulic conductivity of the repellent soil due to the pressure of the ash layer. Splash and erosion rates are bigger in water repellent soils yet erosion rates never exceed 2.5 g m-2 h-1. The fact of wetting increases the runoff and drainage rates in wettable but reduce them in the water repellent soil. An irregular infiltration pattern is observed afterwards. After drying the soil, the increase in runoff indicates a crust formation. Moreover, in water repellent soils part of the repellency is reestablished. These findings demonstrate that the interaction of the soil-ash layer should be considered and better studied in the immediate hydrological response after wildfire due to its particular behavior. References Cerdà, A. and Doerr, S.H., 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena, 74: 256-263. Doerr, S.H., Shakesby, R.A. and Walsh, R.P.D., 2000. Soil Water repellency: Its causes, characteristics and hydro-geomorphological significance. Earth Science Reviews, 51: 33-65. Mallik, A.U., Gimingham, C.H. and Rahman, A.A., 1984. Ecological effects of heater burning. I. Water infiltration, moisture retention and porosity of surface soil. Journal of Ecology, 72: 767-776. Onda, Y., Dietrich, W.E. and Booker, F., 2008. Evolution of overland flow after a severe forest fire, Point Reyes, California. Catena, 72: 13-20. Woods, S.W. and Balfour, V., 2008. The effect of ash on runoff and erosion after a forest wildfire, Montana, U.S.A. International Journal of Wildland Fire, 17(5): 535-548.

Burnt area detection and hotspot analysis of wildfires in Margalla Hills National Park

NASA Astrophysics Data System (ADS)

Khalid, Noora; Ullah, Saleem

2016-07-01

Wildfires have been a growing source for the forest degradation and reduction in carbon sequestration which cause climate change and global warming. Thus, severely affect the ecosystem when not checked. Studies have revealed that land managements that do not use fire reduce the fire incidents by as much as 69 percent. This study focuses on mapping the areas burnt by forest fires owing to both natural and anthropogenic causes and identifying the fire prone areas in biodiversity spot of Islamabad, Margalla Hills National Park. The methodology employed based on using remotely sensed data with the integration of GIS techniques to estimate the area in hectares turned to ashes which ensued from forest fires during summers of 2008, 2010 and 2011 by applying Normalized Burn Ratio. Moreover hotspot analysis has also been used to pin point the locations with frequent fire incidents in the past using Global Positioning System (GPS) acquired coordinates from the fire surveys and official burned area statistics. The results revealed that wildfires destroyed some common regions in three years towards west which comprise of dense woodland comprising mainly Acacia Modesta, Dalbergia sissoo and Pinus longifolia. The calculated burnt area was 516 hectares, 122 hectares and 45 hectares for 2008, 2010 and 2011 respectively. Although a decline in burnt area has been observed owing to responsible management of authorities and development of fire pickets, still measures need to be taken to eradicate the core causes in charge of these fires and to promote reforestation. This study will allow policy makers and regulatory authorities to identify risk prone areas which will assist them in formulating a strategy to suppress fire incidents.

Spatio-temporal effects of low severity grassland fire on soil colour

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerdà, Artemi; Bolutiene, Violeta; Pranskevicius, Mantas; Úbeda, Xavier; Jordán, Antonio; Zavala, Lorena; Mataix-Solera, Jorge

2013-04-01

Fire changes soil properties directly, through temperature, or indirectly with ash deposition and the temporal elimination of vegetal cover. Both influences change soil colour and soil properties. The degree of changes depends on fire severity that has important implications on soil organic matter, texture, mineralogy and hydrological properties and type of ash produced. The ash colour is different according to the temperature of combustion and burned specie and this property will have implications on soil colour. In addition, ash properties have a strong spatial variability. The aim of this work is to study the spatio-temporal effects of a low severity grassland fire on soil colour occurred in Lithuania, near Vilnius city (54° 42' N, 25° 08' E, 158 m.a.s.l.). After the fire it was designed a plot of 20x20m in a burned and unburned flat area. Soil colour was analysed immediately after the fire, and 2, 5, 7 and 9 months after the fire. In each sampling 25 soil samples were collected, carried out to the laboratory, dried at room temperature (20-24° C) and sieved with the <2mm mesh. Soil colour was observed with the Munsell colour chart and the soil chroma value (CV) was observed. Since data did not respected the Gaussian distribution a neperian logarithmic (ln) transformation was applied. Differences among time and between plots were observed with the repeated measures ANOVA test, followed by a Tukey HSD test. Differences were significant at a p<0.05. The spatial variability (SV) was assessed with the coefficient of variation using non transformed data. The results showed differences among time at a p<0.001, treatment at a p<0.01 and time x treatment at a p<0.01. This means that fire during the first 9 months changed significantly soil colour. The CV of the burned plot was lower than the control plot (darker colour), that is attributed to the deposition of charred material and charcoal. This ash produced in this fire was mainly black coloured. With the time the soil of the burned plot became lighter, due the movement of charred material and charcoal in depth through soil profile. After the fire SV was higher in the burned plot (13.27%) than in the unburned plot (7.95%). This major variability might be attributed to ash influence, since this fire did nit had direct effects on soil. Despite the reduced CV, some patches burned at higher severity, and ash was dark and light grey and this might had influences on soil colour SV. In the following measurements SV was very similar, but always slightly higher in the control plot than in the burned plot. Two months, unburned 15.52% and burned, 14.70%. Five months, unburned, 14.78% and burned 14.42%, Seven months, unburned, 15.15% and burned, 14.67%. Nine months, unburned, 18.96% and burned 17.84%. After the fire ash can be (re)distributed uncountable times. In the immediate period after the fire, finner ash produced at higher severities is easily transported by wind and can remix (Pereira et al., 2013a, Pereira et al., 2013b) and change soil colour. In this fire, vegetation recovered very fast, thus this process might occurred only in the first weeks after the fire (Pereira et al., 2013c). Since vegetation recovered fast, soil colour SV depended on carbon and charred material movement in depth soil profile. Further studies are needed on the soil colour evolution after the fire, since can be an indicator of soil properties such as temperature reached with implications in other soil properties. Acknowledgements The authors appreciated the support of the project "Litfire", Fire effects in Lithuanian soils and ecosystems (MIP-048/2011) funded by the Lithuanian Research Council, Spanish Ministry of Science and Innovation for funding through the HYDFIRE project CGL2010-21670-C02-01, FUEGORED (Spanish Network of Forest Fire Effects on Soils http://grupo.us.es/fuegored/) and to Comissionat per a Universitats i Recerca del DIUE de la Generalitat de Catalunya. References Pereira, P. Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2013a) Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development (In press) DOI: 10.1002/ldr.2195 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Martin, D.A., Jordan, A. Burguet, M. (2013b) Effects of fire on ash thickness in a Lithuanian grassland and short-term spatio-temporal changes. Solid Earth Discussions, 4 (1), 1545-1584. doi:10.5194/sed-4-1-2012 Pereira, P., Pranskevicius, M., Cepanko, V., Vaitkute, D., Pundyte, N., Ubeda, X., Mataix-Soler, J., Cerda, A., Martin, D.A. (2013c) Short time vegetation recovers after a spring grassland fire in Lithuania. Temporal and slope position effect, Flamma, 4(1), 13-17.

Rainfall and wet and dry cycle's impact on ash thickness. A laboratory experiment

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Keestra, Saskia; Peters, Piet; Cerdà, Artemi

2016-04-01

Ash is the most important and effective soil protection in the immediate period after the fire (Cerda and Doerr, 2008; Pereira et al., 2015a). This protection can last for days or weeks depending on the fire severity, topography of the burned area and post-fire meteorological conditions. In the initial period after the fire, ash is easily transported by wind. However after the first rainfalls, ash is eroded, or bind in soil surface (Pereira et al., 2013, 2015a). Ash thickness has implications on soil protection. The soil protection against the erosion and the ash capacity to retain water increases with the ash thickness (Bodi et al., 2014). Ash cover is very important after fire because store water and releases into soil a large amount of nutrients, fundamental to vegetation recuperation (Pereira et al., 2014). Despite the importance of ash thickness in post fire environments, little information is available about the effects of rainfall and wet and dry cycle's effects on ash thickness. This work aims to fill this gap. The objective of this study is to investigate the impacts of rainfall and wet and dry cycles in the ash thickness of two different under laboratory conditions. Litter from Oak (Quercus robur) and Spruce (Picea abis) were collected to and exposed during 2 hours to produce ash at 200 and 400 C. Subsequently a layer of 15 mm ash was spread on soil surface in small boxes (24x32 cm) and then subjected to rainfall simulation. Boxes were placed at a 17% of inclination and a rainfall intensity of 55 mm/h during 40 minutes was applied. After the rainfall simulation the plots were stored in an Oven at the temperature of 25 C during four days, in order to identify the effects of wet and dry cycles (Bodi et al., 2013). Ash thickness was measured after the first rainfall (AFR), before the second rainfall (BSR) - after the dry period of 4 days - and after the second rainfall (ASR). In each box a grid with 57 points was designed in order to analyse ash thickness AFR, BSR and ASR. The results showed that AFR, ash thickness was reduced by 7.97% (±18.13) and 32.02 % (±37.44) in the Oak ash produced at 200 C (Oak 200) and 400 C (Oak 400), respectively. The spruce ash layer produced at 200 (Spruce 200) decreased 7.26% (±15.11) and 13.11 % (±18.40) in the ash produced at 400 C (Spruce 400). Before the second rainfall we identified that Oak 200 ash layer reduced approximately 15.95 (±15.81) while Oak 400 decreased 47.98% (±28.97). Spruce 200 ash layer was reduced by 14.52 (±14.57) and Spruce 400 by 18.68 (±17.54). In the last rainfall experiment, it was observed that Oak 200 ash layer decreased 14.88 (±14.09) and Oak 400 ash layer 44.52 (±28.85). Spruce 200 ash layer reduced 13.10 (±14.76) and spruce 400 18.33 (±21.69). The spatial pattern (assessed with Moran's I index) of the ash later of Oak 200 and Oak 400 AFR was significantly clustered (p<0.001). The spatial pattern of Spruce 200 was random (p>0.05) and Spruce 400 significantly clustered (p<0.001). Before the second rainfall, the spatial pattern of Oak 200 and Oak 400 was significantly clustered at a p<0.05 and p<0.001. The same situation was identified in Spruce 200 and Spruce 400 (p<0.001). Finally, ASR, the spatial pattern observed in Oak 200 and Oak 400 was significantly clustered at a p<0.05 and p<0.001. This was also identified in Spruce 200 and Spruce 400. Overall, the thickness decrease was higher in the ash layers produced at high temperature. The differences were mainly observed in oak ash. The dry cycle did not have an important impact on ash thickness in both species as the second rainfall cycle. The results from the Moran's I analysis showed that after the rainfall experiment the ash was mainly concentrated in a specific part of the plot. In this case it was located in the bottom of the experimental plot. Acknowledgments The authors are thankful to the Soil Physics and Land Management Group from Wageningen University, The Netherlands for provide the infrastructure to develop this work, to the RECARE project (grant agreement n° 603498), and to the COST action ES1306: Connecting European Connectivity Research for funding a STSM at the Wageningen University. References Bodi, M., Martin, D.A., Santin, C., Balfour, V., Doerr, S.H., Pereira, P., Cerda, A., Mataix-Solera, J. (2014) Wildland fire ash: production, composition and eco-hydro-geomorphic effects. Earth-Science Reviews, 130, 103-127. Bodi, M.B., Doerr, S.H., Cerda, A., Mataix-Solera, J. (2013) Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma, 191, 14-23. Cerdà, A., Doerr, S.H., 2008. The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena 74, 256-263. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Jordan, A. Burguet, M. (2013) Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania, Solid Earth, 4, 153-165. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2015) Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development, 26, 180-192. Pereira, P., Jordan, A., Cerda, A., Martin, D. 2015a. Editorial: The role of ash in fire-affected ecosystems, Catena, 135, 337 - 379. Pereira, P., Úbeda, X., Martin, D., Mataix-Solera, J., Cerdà, A., Burguet, M. (2014)Wildfire effects on extractable elements in ash from a Pinus pinaster forest in Portugal, Hydrological Processes, 28, 3681-3690

Methods to Improve Survival and Growth of Planted Alternative Species Seedlings in Black Ash Ecosystems Threatened by Emerald Ash Borer

Treesearch

Nicholas Bolton; Joseph Shannon; Joshua Davis; Matthew Grinsven; Nam Noh; Shon Schooler; Randall Kolka; Thomas Pypker; Joseph Wagenbrenner

2018-01-01

Emerald ash borer (EAB) continues to spread across North America, infesting native ash trees and changing the forested landscape. Black ash wetland forests are severely affected by EAB. As black ash wetland forests provide integral ecosystem services, alternative approaches to maintain forest cover on the landscape are needed. We implemented simulated EAB infestations...

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-12-31

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content`s deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research for many years on what might be done to minimize the adverse effects of ash on boiler performance. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effectmore » these firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS Concentric Firing System on the propensity for boiler wall ash deposition. For this study, CFS yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

An Experimental Study of the Effects of Litter and Duff Consumption and Ash Formation on Post-Fire Runoff.

NASA Astrophysics Data System (ADS)

Woods, S. W.; Balfour, V.

2007-12-01

Consumption of the litter and duff layers in forest wildfires can lead to substantial increases in the frequency and magnitude of overland flow. These increases result from the loss of storage in the organic surface layer, reduced surface roughness, and from sealing of the exposed mineral soil surface. The presence of an ash layer may accentuate surface sealing by providing an additional source of fine material, or it may reduce runoff by storing rainfall and by protecting the soil surface from raindrop impacts. We used simulated rainfall experiments to assess the effects of litter and duff consumption and the presence of ash layers of varying thickness on post fire runoff at two forested sites in western Montana, one with sandy loam soils formed out of granodiorite and the other with gravelly silt loam soils formed out of argillite. At each site we measured the runoff from simulated rainfall in replicated 0.5 m2 plots before and after application of the following treatments: 1) burning with a fuel load of 90 Mg ha-1, 2) manual removal of the litter and duff layers, 3) addition of 0.5, 2.5 and 5 cm of ash to plots from which the litter and duff had previously been removed, and 4) addition of the same depths of ash to burned plots at the sandy loam site. In the burned plots the surface litter and duff layers were completely consumed and a <1cm layer of black and gray ash and char was formed, indicating a moderate severity burn. The mean soil temperature in the upper 1 cm of the mineral soil was 70° C, and there was no detectable increase in water repellency. The mean final infiltration capacity of the burned sandy loam plots was 35 mm hr-1 compared to a pre-fire mean of 87 mm hr-1, while in the gravelly silt loam plots the pre- and post burn infiltration capacities (27 and 31 mm hr- 1) were not significantly different. Manual removal of the litter and duff layers reduced the mean final infiltration capacity in the sandy loam plots from 64 mm hr-1 to 40 mm hr-1 and in the gravelly silt loam plots from 23 mm hr-1 to 16 mm hr-1. We attribute decreases in infiltration due to the burning and duff removal treatments primarily to surface sealing. In the sandy loam plots, burning may have had a greater effect on infiltration than duff removal because the thin ash layer in the burned plots provided an additional source of fine material. In the gravelly silt loam plots, macropores located around rock fragments helped to minimize sealing effects. The addition of 0.5 cm of ash to the burned granitic plots resulted in a 20 mm hr-1 decrease in the final infiltration rate, and this was also probably due to surface sealing. However, the overall effect of ash addition was to increase the cumulative infiltration in proportion to the ash thickness and to maintain a higher average infiltration rate, indicating that while thin (<1 cm) ash layers may promote sealing, thicker ash layers help to reduce the runoff rate by providing additional storage for rainfall and by protecting the soil surface from raindrop impacts.

Long-term changes in soil erosion due to forest fires. A rainfall simulation approach in Eastern Spain

NASA Astrophysics Data System (ADS)

Cerdà, Artemi; Keesstra, Saskia; Pereira, Paulo; Matrix-Solera, Jorge; Giménez-Morera, Antonio; Úbeda, Xavier; Francos, Marcos; Alcañiz, Meritxell; Jordán, Antonio

2016-04-01

Soils are affected by the impacts of wildfires (Dlapa et al., 2013; Pereira et al., 2014; Tsibart et al., 2014; Dlapa et al., 2015, Hedo et al., 2015; Tessler et al., 2015). Soil erosion rates are highly affected by forest fires due to the removal of the above ground vegetation, the heat impact on the soil, the reduction of the organic matter, the ash cover, and the changes introduced by the rainfall on the soil surface (Lasanta and Cerdà, 2005; Mataix-Solera et al., 2011; Novara et al., 2011; Novara et al., 2013; Keesstra et al., 2014; Hedo et al., 2015; Pereira, 2015). Most of the research carried out on forest fire affected land paid attention to the "window of disturbance", which is the period that the soil losses are higher than before the forest fire and that last for few years (Cerdà, 1998a; Cerdà 1998b, Pérez-Cabello et al., 2011; Bodí et al., 2011; Bodí et al., 2012; Pereira et al., 2013: Pereira et al., 2015). However, the spatial and temporal variability of soil erosion is very high as a result of the uneven temporal and spatial distribution of the rainfall (Novara et al., 2011; Bisantino et al., 2015; Gessesse et al., 2015; Ochoa et al., 2015), and the window of disturbance cannot be easily found under natural rainfall. In order to understand the evolution of soil erosion after forest fires it is necessary to monitor fire affected sites over a long period of time, which will enable the assessment of the period affected by the window of disturbance (see Cerdà and Doerr, 2005). However, it is also possible to do measurements and experiments in areas with a different fire history. This will give us information about the temporal changes in soil erosion after forest fire. To reduce the spatial variability of rainfall we can use simulated rainfall that can be applied at multiple site with the same rainfall intensity and duration. For this purpose rainfall simulation can be of great help, in the laboratory (Moreno et al., 2014; Sadegui et al., 2015; Carvalho et al., 2015; Lassu et al., 2015) or in the field (Cerdà et al., 1998c; Jordán et al., 2009; Prosdocimi et al., 2016). In order to determine how fire and post-fire changes change soil erosion rates we selected 12 research sites at the study area of the Massís del Caroig, Eastern Spain, which suffered different fires in the last century. The parent material is limestone in all study sites and the mean annual rainfall ranges from 480 to 550 mm per year in average. The vegetation consists of scrubland (Maquia) with different species. In the years after the fire Brachypodium retusum, Thymus vulgaris, Fumana Ericoides, Cistus Albidus, Ulex parviflorus or Rosmarinus officinalis regenerated, but after some years dense shrub cover develops with typical species such as Quercus coccifera, Quercus ilex, Pistacia lentiscus and Junyperus oxycedurs. Soils are shallow (0-30 cm depth) and distributed in pockets of soil mixed with rock outcrops. All the selected plots were located on the middle tram of the slopes to avoid differences, although previous studies showed no differences in infiltration rates, overland flow and soil erosion on the different trams of the slopes on limestone (Cerdà, 1998d). Each site was selected upon the last fire registered: 0, 1, 2, 3, 5, 9, 16, 24, 33, 44, 51, and 63 years after the last fire. The measurements were carried out in August 2013 by means of a portable rainfall simulator (Cerdà et al., 2009; Iserloh et al., 2013). Ten plots of 0.25 m2 were selected at each site. Rainfall simulation at 55 mm h-1 during one hour was applied. The results show that immediately after the wildfires the soil erosion was negligible due to the ash cover, which acted as mulch, meanwhile after few months (1 year after the fire) the highest soil losses were measured. After 5 years the soil losses had reduced significantly and after 16 years were negligible. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project) and by the Spanish Government with the research Project CGL2013- 47862-C2-1-R. References Bisantino T., Bingner R., Chouaib W., Gentile F., Trisorio Liuzzi G. 2015. Estimation of runoff, peak discharge and sediment load at the event scale in a medium-size mediterranean watershed using the annagnps model. Land Degradation and Development, 26 (4), 340-355. DOI: 10. 1002/ldr. 2213 Bodí, M.B., Doerr, S.H., Cerdà, A., Mataix-Solera, J. 2012. Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma, 191, 14-23. DOI: 10.1016/j.geoderma.2012.01.006 Bodí, M.B., Mataix-Solera, J., Doerr, S.H., Cerdà, A. 2011. The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type,burn severity and total organic carbon content. Geoderma, 160 (3-4), 599-607. Carvalho, S.C.P., de Lima, J.L.M.P., de Lima, M.I.P. 2015. Increasing the Rainfall Kinetic Energy of Spray Nozzles by using Meshes. Land Degradation and Development, DOI: 10.1002/ldr.2349 Cerdà, A. 1998a.The influence of aspect and vegetation on seasonal changes in erosion under rainfall simulation on a clay soil in Spain. Canadian Journal of Soil Science, 78 (2), 321-330. Cerdà, A. 1998b. Changes in overland flow and infiltration after a rangeland fire in a Mediterranean scrubland. Hydrological Processes, 12 (7), 1031-1042. Cerdà, A. 1998c. Post-fire dynamics of erosional processes under Mediterranean climatic conditions(1998) Zeitschrift fur Geomorphologie, 42 (3), 373-398. Cerdà, A. 1998d. The influence of geomorphological position and vegetation cover on the erosional and hydrological processes on a Mediterranean hillslope. Hydrological Processes, 12 (4), 661-671. Cerdà, A., Doerr, S.H. 2005.Influence of vegetation recovery on soil hydrology and erodibility following fire: An 11-year investigation International Journal of Wildland Fire, 14 (4), 423-437. DOI: 10.1071/WF05044 Cerdà, A., Jurgensen, M.F., Bodi, M.B. 2009. Effects of ants on water and soil losses from organically-managed citrus orchards in eastern Spain. Biologia, 64 (3), 527-531. DOI: 10.2478/s11756-009-0114-7 Dlapa P., Bodí M.B., Mataix-Solera J., Cerdà A., Doerr S.H. 2015. Organic matter and wettability characteristics of wildfire ash from Mediterranean conifer forests. Catena, 135, 369-376. DOI: 10.1016/j.catena.2014.06.018 Dlapa, P., Bodí, M.B., Mataix-Solera, J., Cerdà, A., Doerr, S.H. 2013. FT-IR spectroscopy reveals that ash water repellency is highly dependent on ash chemical composition. Catena, 108, 35-43. DOI: 10.1016/j.catena.2012.02.011 Gessesse B., Bewket W., Bräuning A. 2015. Model-Based Characterization and Monitoring of Runoff and Soil Erosion in Response to Land Use/land Cover Changes in the Modjo Watershed, Ethiopia. (2015) Land Degradation and Development, 26 (7), 711-724.. DOI: 10. 1002/ldr. 2276 Hedo J., Lucas-Borja M. E., Wic C., Andrés-Abellán M., De Las Heras J. 2015. Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands. Solid Earth, 6 (1), 243-252. DOI: 10. 5194/se-6-243-2015 Hedo de Santiago, J., Lucas-Borja, M.E., Wic-Baena, C., Andrés-Abellán, M., de las Heras, J. 2015. Effects of thinning and induced drought on microbiological soil properties and plant species diversity at dry and semiarid locations. Land Degradation and Development, DOI: 10.1002/ldr.2361 Iserloh, T., Ries, B.J., Cerdà, A., Echeverría, M.T., Fister, W., Geißler, C., Kuhn, N.J., León, F.J., Peters, P., Schindewolf, M., Schmidt, J., Scholten, T., Seeger, M. 2013. Comparative measurements with seven rainfall s simulators on uniform bare fallow land. Zeitschrift fur Geomorphologie, 57 (1 SUPPL. 1), 1-10. DOI: 10.1127/0372-8854/2012/S-00085 Jordán-López, A., Martínez-Zavala, L., Bellinfante, N. 2009. Impact of different parts of unpaved forest roads on runoff and sediment yield in a Mediterranean area. Science of the total environment, 407(2), 937-944. Keesstra, S.D., Maroulis, J., Argaman, E., Voogt, A., Wittenberg, L, 2014. Effects of controlled fire on hydrology and erosion under simulated rainfall. Cuadernos de Investigación Geográfica 40, 269-293. DOI: 10.18172/cig.2532 Lasanta, T., Cerdà, A. 2005. Long-term erosional responses after fire in the Central Spanish Pyrenees: 2. Solute reléase. Catena, 60 (1), 81-100. DOI: 10.1016/j.catena.2004.09.005 Lassu, T., Seeger, M., Peters, P., Keesstra, S.D. 2015. The Wageningen Rainfall Simulator: Set-up and Calibration of an Indoor Nozzle-Type Rainfall Simulator for Soil Erosion Studies. Land Degradation and Development, 26 (6), 604-612. DOI: 10.1002/ldr.2360 Mataix-Solera, J., Cerdà, A., Arcenegui, V., Jordán, A., Zavala, L.M. 2011. Fire effects on soil aggregation: A review. Earth-Science Reviews, 109 (1-2), 44-60. DOI: 10.1016/j.earscirev.2011.08.002 Moreno-Ramón, H., Quizembe, S.J., Ibáñez-Asensio, S. 2014. Coffee husk mulch on soil erosion and runoff: Experiences under rainfall simulation experiment. Solid Earth, 5 (2), 851-862. DOI: 10.5194/se-5-851-2014 Novara A., Gristina L., Rühl J., Pasta S., D'Angelo G., La Mantia T., Pereira P. 2013. Grassland fire effect on soil organic carbon reservoirs in a semiarid environment. Solid Earth, 4 (2), 381-385.. DOI: 10. 5194/se-4-381-2013 Novara, A., Gristina, L., Bodì, M.B., Cerdà, A. 2011. The impact of fire on redistribution of soil organic matter on a Mediterranean hillslope under maquia vegetation type Land Degradation and Development, 22 (6), 530-536. DOI: 10.1002/ldr.1027 Novara, A., Gristina, L., Saladino, S.S., Santoro, A., Cerdà, A. 2011. Soil erosion assessment on tillage and alternative soil managements in a Sicilian vineyard. Soil and Tillage Research, 117, 140-147. DOI: 10.1016/j.still.2011.09.007 Ochoa-Cueva P., Fries A., Montesinos P., Rodríguez-Díaz J. A., Boll J. 2015. Spatial Estimation of Soil Erosion Risk by Land-cover Change in the Andes OF Southern Ecuador. Land Degradation and Development, 26 (6), 565-573DOI: 10. 1002/ldr. 2219 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Arcenegui, V., Zavala, L.M. 2015. Modelling the Impacts of Wildfire on Ash Thickness in a Short-Term Period. Land Degradation and Development, 26 (2), 180-192. DOI: 10.1002/ldr.2195 Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Martin, D., Jordán, A., Burguet, M. 2013. Spatial models for monitoring the spatio-temporal evolution of ashes after fire and ash; A case study of a burnt grassland in Lithuania. Solid Earth, 4 (1), 153-165 DOI: 10.5194/se-4-153-2013 Pereira, P., Jordán, A., Cerdà, A., Martin, D. 2015. Editorial: The role of ash in fire-affected ecosystem. Catena, . DOI: 10.1016/j.catena.2014.11.016 Pereira, P., Úbeda, X., Mataix-Solera, J., Oliva, M., Novara, A.Short-term changes in soil Munsell colour value, organic matter content and soil water repellency after a spring grassland fire in Lithuania (2014) Solid Earth, 5 (1), 209-225. DOI: 10.5194/se-5-209-2014 Pérez-Cabello, F., Cerdà, A., de la Riva, J., Echeverría, M.T., García-Martín, A., Ibarra, P., Lasanta, T., Montorio, R., Palacios, V. 2012. Micro-scale post-fire surface cover changes monitored using high spatial resolution photography in a semiarid environment: A useful tool in the study of post-fire soil erosion processes. Journal of Arid Environments, 76 (1), 88-96. DOI: 10.1016/j.jaridenv.2011.08.007 Prosdocimi,M., Jordán, A., Tarolli, P., Keesstra, S., Novara, A., Cerdà, A. 2016. The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards. Science of The Total Environment, 547, 15 ,323-330, doi:10.1016/j.scitotenv.2015.12.076 Sadeghi, S.H.R., Gholami, L., Sharifi, E., Khaledi Darvishan, A., Homaee, M. 2015. Scale effect on runoff and soil loss control using rice mulch under laboratory conditions. Solid Earth, 6 (1), 1-8. DOI: 10.5194/se-6-1-2015 Tessler, N., Sapir, Y., Wittenberg, L., Greenbaum, N. 2015. Recovery of Mediterranean Vegetation after Recurrent Forest Fires: Insight from the 2010 Forest Fire on Mount Carmel, Israel. Land Degradation and Development, DOI: 10.1002/ldr.2419 Tsibart, A., Gennadiev, A., Koshovskii, T., Watts, A. 2014. Polycyclic aromatic hydrocarbons in post-fire soils of drained peatlands in western Meshchera (Moscow region, Russia). Solid Earth, 5 (2), 1305-1317. DOI: 10.5194/se-5-1305-2014 Wang, C., Wang, G., Wang, Y., Rafique, R., Ma, L., Hu, L., Luo, Y. 2015. Fire Alters Vegetation and Soil Microbial Community in Alpine Meadow. Land Degradation and Development, . DOI: 10.1002/ldr.2367

Land abandonment, fire recurrence and soil carbon content in the Macizo del Caroig, Eastern Spain

NASA Astrophysics Data System (ADS)

Cerdá, A.; González Peñaloza, F.; Santín, C.; Doerr, S. H.

2012-04-01

During the last 50 years two main forces have driven the fate of Mediterranean landscapes: land abandonment and forest fires (MacDonald et al., 2000; Moreira et al., 2001). Due to the economical changes suffered by the of the Mediterranean countries after the Second World War, the population migrated from the rural to the urban areas, and from South to North Europe. The land abandonment allowed the vegetation to recover and, as a consequence, an increase in forest fire took place. The soils of the abandoned land recovered the vegetation and litter layers, and consequently changes in soil properties have being found. One of these changes is the increase of soil carbon content, which is due both to vegetation recovery and to fire occurrence that increases the ash and pyrogenic carbon content in soils. Twenty plots were selected in the Macizo del Caroig in Eastern Spain on soils developed on limestone. The period of abandonment and the forest fires that had affected each plot were determined by interviews with the owners, farmers and shepherds. In addition, six (three + three) plots were selected as forest (no plough) and cultivated control plots. Each plot was sampled (10 random samples) and the organic carbon content determined. The results show that the cultivated plots have organic matter contents of 1.02 %, and the forest (Quercus ilex sp.) plots reach the highest value: 14.98 %. Within those we found values that range from 2.34 %, in the recently abandoned plots (10 year abandonment), to values of 8.23 % in the 50 year old abandoned fields.The results demonstrate that there is a recovery of the organic carbon in abandoned soils and that the forest fires do no affect this trend. The increase of soil organic matter after abandonment is a result of the recovery of vegetation(Debussche et al., 2001), which is the consequence of the end of the disturbance of forest that have affected the Mediterranean for millennia (Barbero et al., 1990). The colonization of the abandoned fields by the vegetation is very efficient (Ne'eman and Izhaki, 1996) and fire adapted species are the main types, which demonstrates that fire is part of the Mediterranean ecosystems (Pausas, 1999). The fire was not found here as a factor increasing the organic carbon in the abandoned soils, although it was found in a nearby area (Novara et al., 2011). This research confirms that the soil development in Mediterranean Type-Ecosystems (Cerdà et al., 2010) is being affected by land abandonment and fire (Doerr and Cerdà, 2005).

Predicting the ash behavior during biomass combustion in FBC conditions by combining advanced fuel analyses with thermodynamic multicomponent equilibrium calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skrifvars, B.J.; Blomquist, J.P.; Hupa, M.

1998-12-31

Previous work at Aabo Akademi University has focused on identification and quantification of various sintering mechanisms which are relevant for problematic ash behavior during biomass combustion in fluidized bed combustion conditions, and on multi-component multi-phase thermodynamic phase equilibrium calculations of ash chemistry in these conditions. In both areas new information has been developed and useful modeling capabilities have been created. Based on the previous work, the authors now present a novel approach of using a combination of an advanced fuel analysis method and thermodynamic phase equilibrium calculations to predict the chemical and thermal behavior of the ash when firing biomass.more » Four different fuels [coal, forest residues, wood chips, and a mixture of forest residue and wood chips] were analyzed using the chemical fractionation analysis technique. Based on the results from these analyses, the authors formed two different ash fractions, (1) one fine sized fraction consisting of those elements found in the water and weak acid leach, and (2) a coarse ash particle fraction consisting of those elements found in the strong acid leach and non-leachable rest. The small sized ash fraction was then assumed to be carried up with the flue gases and consequently formed the base for any ash related problems in the flue gas channel. This fraction was therefore analyzed on its chemical and thermal behavior using multi-component multi-phase equilibrium calculations, by which the composition and the melting behavior was estimated as a function of the temperature. The amount of melt, which has earlier been found to be strongly related to problematic ash behavior, was finally expressed as a function of the temperature for the fraction. The coarse fraction was treated separately. Here the authors estimate the composition only. The paper discusses the results and their relevance to full scale combustion.« less

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-07-01

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content's deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research what might be done to minimize the adverse effects of ash on boiler performance for many years. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effect thesemore » firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS{trademark} yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS{trademark} yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

Emerald ash borer aftermath forests: the future of ash ecosystems

Treesearch

Kathleen S. Knight; Daniel A. Herms; John Cardina; Robert Long; Kamal J.K. Gandhi; Catharine P. Herms

2011-01-01

The effects of emerald ash borer (EAB) (Agrilus planipennis) on forest ecosystems are being studied through a collaborative research program between the U.S. Forest Service and The Ohio State University. We are monitoring ash demographics, understory light availability, EAB population dynamics, native and non-native plants, and effects of ash...

Empirical relationships between tree fall and landscape-level amounts of logging and fire

PubMed Central

Blanchard, Wade; Blair, David; McBurney, Lachlan; Stein, John; Banks, Sam C.

2018-01-01

Large old trees are critically important keystone structures in forest ecosystems globally. Populations of these trees are also in rapid decline in many forest ecosystems, making it important to quantify the factors that influence their dynamics at different spatial scales. Large old trees often occur in forest landscapes also subject to fire and logging. However, the effects on the risk of collapse of large old trees of the amount of logging and fire in the surrounding landscape are not well understood. Using an 18-year study in the Mountain Ash (Eucalyptus regnans) forests of the Central Highlands of Victoria, we quantify relationships between the probability of collapse of large old hollow-bearing trees at a site and the amount of logging and the amount of fire in the surrounding landscape. We found the probability of collapse increased with an increasing amount of logged forest in the surrounding landscape. It also increased with a greater amount of burned area in the surrounding landscape, particularly for trees in highly advanced stages of decay. The most likely explanation for elevated tree fall with an increasing amount of logged or burned areas in the surrounding landscape is change in wind movement patterns associated with cutblocks or burned areas. Previous studies show that large old hollow-bearing trees are already at high risk of collapse in our study area. New analyses presented here indicate that additional logging operations in the surrounding landscape will further elevate that risk. Current logging prescriptions require the protection of large old hollow-bearing trees on cutblocks. We suggest that efforts to reduce the probability of collapse of large old hollow-bearing trees on unlogged sites will demand careful landscape planning to limit the amount of timber harvesting in the surrounding landscape. PMID:29474487

Empirical relationships between tree fall and landscape-level amounts of logging and fire.

PubMed

Lindenmayer, David B; Blanchard, Wade; Blair, David; McBurney, Lachlan; Stein, John; Banks, Sam C

2018-01-01

Large old trees are critically important keystone structures in forest ecosystems globally. Populations of these trees are also in rapid decline in many forest ecosystems, making it important to quantify the factors that influence their dynamics at different spatial scales. Large old trees often occur in forest landscapes also subject to fire and logging. However, the effects on the risk of collapse of large old trees of the amount of logging and fire in the surrounding landscape are not well understood. Using an 18-year study in the Mountain Ash (Eucalyptus regnans) forests of the Central Highlands of Victoria, we quantify relationships between the probability of collapse of large old hollow-bearing trees at a site and the amount of logging and the amount of fire in the surrounding landscape. We found the probability of collapse increased with an increasing amount of logged forest in the surrounding landscape. It also increased with a greater amount of burned area in the surrounding landscape, particularly for trees in highly advanced stages of decay. The most likely explanation for elevated tree fall with an increasing amount of logged or burned areas in the surrounding landscape is change in wind movement patterns associated with cutblocks or burned areas. Previous studies show that large old hollow-bearing trees are already at high risk of collapse in our study area. New analyses presented here indicate that additional logging operations in the surrounding landscape will further elevate that risk. Current logging prescriptions require the protection of large old hollow-bearing trees on cutblocks. We suggest that efforts to reduce the probability of collapse of large old hollow-bearing trees on unlogged sites will demand careful landscape planning to limit the amount of timber harvesting in the surrounding landscape.

Impact of Wildfire on Solute Release in Forested Catchments, Jemez River, New Mexico, USA

NASA Astrophysics Data System (ADS)

Sanchez, R. A.; Meixner, T.; McIntosh, J. C.; Chorover, J.

2017-12-01

Wildfires represent a large disturbance to the hydrology and biogeochemistry of forested catchments. The number, size and severity of wildfires have significantly increased in the western United States since 1990. Nutrients and other elements (e.g. Ca) that were taken up and stored by biomass are released from burned vegetation during forest fires and transported downgradient via overland flow, shallow subsurface flow, and/or deep groundwater flow. Ash accumulations on hillslopes may also store particulate carbon and contain elevated concentrations of elements that maybe leached into surface and ground water over extended periods of time. In 2013, the Thompson Ridge wildfire burned headwater catchments in the Jemez River Basin Critical Zone Observatory (JRB-CZO) within the Valles Caldera National Preserve, New Mexico USA. The burn severity and area impacted were different in the three headwater catchments. This study investigated the impact of the wildfire on surface water quality, including how the fire-induced impacts evolved with time, and how biogeochemical processes controlled post-fire solute concentrations in the surface water. Comparison of pre- and post-fire surface water solute chemistry shows increases in major cations and anions following fire. Increases in nitrate and sulfate concentrations in streams after the wildfire were likely from leaching of burned biomass. The elevated NO3- and SO42- concentrations persisted for over two years, and were even higher during spring snowmelt. Meanwhile, base cation concentrations increased immediately, within a few weeks after the fire, likely related to leaching from combusted organic matter; and, over a period of approximately two months, base cation concentrations returned to pre-fire levels. Trace element behavior was also altered by fire. For example, while pre-fire aluminum concentrations in stream flow increased significantly during the wet seasons (snowmelt and monsoons), the post-fire observations do not show significant changes with increase in discharge.

Chemistry of burning the forest floor during the FROSTFIRE experimental burn, interior Alaska, 1999

USGS Publications Warehouse

Harden, J.W.; Neff, J.C.; Sandberg, D.V.; Turetsky, M.R.; Ottmar, R.; Gleixner, G.; Fries, T.L.; Manies, K.L.

2004-01-01

Wildfires represent one of the most common disturbances in boreal regions, and have the potential to reduce C, N, and Hg stocks in soils while contributing to atmospheric emissions. Organic soil layers of the forest floor were sampled before and after the FROSTFIRE experimental burn in interior Alaska, and were analyzed for bulk density, major and trace elements, and organic compounds. Concentrations of carbon, nutrients, and several major and trace elements were significantly altered by the burn. Emissions of C, N, and Hg, estimated from chemical mass balance equations using Fe, Al, and Si as stable constituents, indicated that 500 to 900 g C and up to 0 to 4 ?? 10-4 g Hg/M2 were lost from the site. Calculations of nitrogen loss range from -4 to +6 g/m2 but were highly variable (standard deviation 19), with some samples showing increased N concentrations post-burn potentially from canopy ash. Noncombustible major nutrients such as Ca and K also were inherited from canopy ash. Thermogravimetry indicates a loss of thermally labile C and increase of lignin-like C in char and ash relative to unburned counterparts. Overall, atmospheric impacts of boreal fires include large emissions of C, N and Hg that vary greatly as a function of severe fire weather and its access to deep organic layers rich in C, N, and Hg. In terrestrial systems, burning rearranges the vertical distribution of nutrients in fuels and soils, the proximity of nutrients and permafrost to surface biota, and the chemical composition of soil including its nutrient and organic constituents, all of which impact C cycling. Copyright 2004 by the American Geophysical Union.

Crew Earth Observations (CEO) by Expedition Five Crew

NASA Image and Video Library

2002-10-30

ISS005-E-19016 (30 October 2002) --- The three-member crew of the Expedition Five mission onboard the International Space Station was able to observe Mt. Etna’s spectacular eruption, and photograph the details of the eruption plume and smoke from fires triggered by the lava as it flowed down the 11,000 ft mountain. This image and a second image (ISS005-E-19024) are looking obliquely to the southeast over the island of Sicily. This wide view shows the ash plume curving out toward the horizon, caught first by low-level winds blowing to the southeast, and to the south toward Africa at higher altitudes. Ashfall was reported in Libya, more than 350 miles away. The lighter-colored plumes downslope and north of the summit (see detailed view taken the same day, ISS005-E-19024) are produced by forest fires set by lava flowing into the pine forests on the slope of the mountain. The detailed image provides a more three-dimensional profile of the eruption plume. This eruption was one of Etna’s most vigorous in years, volcanologists reported this week. The eruption was triggered by a series of earthquakes on October 27, 2002, they said. These images were taken on October 30. Although schools were closed and air traffic was diverted because of the ash, no towns or villages were reported to have been threatened by the lava flow.

Crew Earth Observations (CEO) by Expedition Five Crew

NASA Image and Video Library

2002-10-30

ISS005-E-19024 (30 October 2002) --- The three-member crew of the Expedition Five mission onboard the International Space Station was able to observe Mt. Etna’s spectacular eruption, and photograph the details of the eruption plume and smoke from fires triggered by the lava as it flowed down the 11,000 ft mountain. This image and a second image (ISS005-E-19016) are looking obliquely to the southeast over the island of Sicily. The wider view (ISS005-E-19024) shows the ash plume curving out toward the horizon, caught first by low-level winds blowing to the southeast, and to the south toward Africa at higher altitudes. Ashfall was reported in Libya, more than 350 miles away. The lighter-colored plumes downslope and north of the summit seen in this frame are produced by forest fires set by lava flowing into the pine forests on the slope of the mountain. This image provides a more three-dimensional profile of the eruption plume. This eruption was one of Etna’s most vigorous in years, volcanologists reported this week. The eruption was triggered by a series of earthquakes on October 27, 2002, they said. These images were taken on October 30. Although schools were closed and air traffic was diverted because of the ash, no towns or villages were reported to have been threatened by the lava flow.

Mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil - an attempt to solve the presence of hematite and maghemite in topsoils in a temperate region

NASA Astrophysics Data System (ADS)

Nørnberg, Per; Vendelboe, Anders L.; Gunnlaugsson, Haraldur P.; Merrison, Jonathan P.; Finster, Kai; Jensen, Svend K.

2010-05-01

Isolated soil spots, a few square metres in size, as red as Munsell colour 10R ¾ are found in Denmark. These spots are well known as places that have been exposed to fire. However, a long-standing unresolved puzzle is the presence of extended areas with high iron content (8-40 %) where goethite and ferrihydrite are present in the topsoil along with hematite and maghemite. Hematite and particularly maghemite would normally not be expected to occur under the temperate humid Danish climate, but be interpreted as the result of high temperature as found in tropical areas or after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this iron mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down to 10 cm depth. This was not observed at the natural sites, which contained a uniform mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire furthermore left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which is in contrast to the natural sites. Physical and chemical date as well as XRD, Mössbauer spectroscopic data and TEM micrographs from the sites will be presented. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to fire, but may rather result from long term transformation within a reducing environment, possibly involving microorganisms. References: Nørnberg, P., Vendelboe, A.L., Gunnlaugsson, H.P., Merrison, J.P., Finster, K., Jensen, S.K. 2009 Mineralogy after an experimental forest fire on Quaternary soil goethite, compared with a hematite, maghemite, goethite containing topsoil. Clay Minerals, 44, 239-247. Nørnberg, P., Gunnlaugsson, H.P., Merrison, J.P., Vendelboe, A.L. 2009: Salten Skov I: A Martian dust analogue. Planetary and Space Science, 57, 628-631. Nørnberg, P., Schwertmann, U., Stanjek, C.B., An¬dersen, T., Gunnlaugsson, H.P. 2004: Mineralogy of Quaternary iron oxide rich formations in Denmark.Clay Minerals, 39, 85-98.

[Soil functioning in foci of Siberian moth population outbreaks in the southern taiga subzone of Central Siberia].

PubMed

Krasnoshchekov, Iu N; Beskorovaĭnaia, I N

2008-01-01

The results of experimental studies on the contribution of zoogenic debris to transformation of soil properties in the southern taiga subzone of Central Siberia are analyzed. They show that water-soluble carbon outflow from the forest litter increases by 21-26% upon a Siberian moth invasion, with this value decreasing to 14% one year later. The burning of forest in an area completely defoliated by the pest leads to changes in the stock, fractional composition, actual acidity, and ash element contents of the litter. The litter-dwelling invertebrate assemblage is almost completely destroyed by fire and begins to recover only after two years.

Quantifying change in riparian ash forests following the introduction of EAB in Michigan and Indiana

Treesearch

Susan J. Crocker; Dacia M. Meneguzzo

2012-01-01

The emerald ash borer (Agrilus planipennis Fairmaire; Coleoptera: Buprestidae; EAB) is an introduced beetle that kills ash (Fraxinus spp.) trees. While most EAB-related ash mortality has been documented in urban areas, the effects of EAB in forested settings, particularly in riparian forests, are not well known. This study utilizes...

Fire severity effects on ash extractable Total Phosphorous

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Úbeda, Xavier; Martin, Deborah

2010-05-01

Phosphorous (P) is a crucial element to plant nutrition and limits vegetal production. The amounts of P in soil are lower and great part of this nutrient is absorbed or precipitated. It is well known that fire has important implications on P cycle, that can be lost throughout volatilization, evacuated with the smoke, but also more available to transport after organic matter mineralization imposed by the fire. The release of P depends on ash pH and their chemical and physical characteristics. Fire temperatures impose different severities, according to the specie affected and contact time. Fire severity is often evaluated by ash colour and this is a low-cost and excellent methodology to assess the fire effects on ecosystems. The aim of this work is study the ash properties physical and chemical properties on ash extractable Total Phosphorous (TP), collected in three wildfires, occured in Portugal, (named, (1) Quinta do Conde, (2) Quinta da Areia and (3) Casal do Sapo) composed mainly by Quercus suber and Pinus pinaster trees. The ash colour was assessed using the Munsell color chart. From all three plots we analyzed a total of 102 ash samples and we identified 5 different ash colours, ordered in an increasing order of severity, Very Dark Brown, Black, Dark Grey, Very Dark Grey and Light Grey. In order to observe significant differences between extractable TP and ash colours, we applied an ANOVA One Way test, and considered the differences significant at a p<0.05. The results showed that significant differences in the extractable TP among the different ash colours. Hence, to identify specific differences between each ash colour, we applied a post-hoc Fisher LSD test, significant at a p<0.05. The results obtained showed significant differences between the extractable TP from Very dark Brown and Black ash, produced at lower severities, in relation to Dark Grey, Very Dark Grey and Light Grey ash, generated at higher severities. The means of the first group were higher than the observed in the second one. This indicates that ash produced lower temperatures release in solution higher amounts of TP. These divergences occur due temperature of combustion, affected specie, ash pH values and CaCO3 content, which affects the quantity of this element in solution. Discussions about these effects will be accurate in the communication.

Physiological and behavioral responses of an arboreal mammal to smoke and charcoal-ash substrate.

PubMed

Nowack, Julia; Stawski, Clare; Körtner, Gerhard; Geiser, Fritz

2018-02-01

The recent observation that torpor plays a key role in post-fire survival has been mainly attributed to the reduced food resources after fires. However, some of these adjustments can be facilitated or amplified by environmental changes associated with fires, such as the presence of a charcoal-ash substrate. In a previous experiment on a small terrestrial mammal the presence of charcoal and ash linked to food restriction intensified torpor use. However, whether fire cues also act as a trigger of torpor use when food is available and whether they affect other species including arboreal mammals remains elusive. To evaluate whether smoke, charcoal and ash can act as proximate triggers for an impending period of food shortage requiring torpor for mammals, we conducted an experiment on captive sugar gliders (Petaurus breviceps), a small, arboreal marsupial, housed in outside aviaries under different food regimes and natural ambient conditions. When food was available, fire simulation via exposure to smoke and charcoal-ash substrate caused a significant earlier start of activity and a significant decrease in resting body temperature. In contrast, only when food was withheld, did smoke and charcoal-ash exposure significantly enhance torpor depth and duration. Thus, our study not only provides evidence that fire simulation does affect arboreal and terrestrial species similarly, but also suggests that smoke and ash were presumably selected as cues for torpor induction because they indicate an impending lack of food. Copyright © 2017 Elsevier Inc. All rights reserved.

Erupting Volcano Mount Etna

NASA Technical Reports Server (NTRS)

2002-01-01

Expedition Five crew members aboard the International Space Station (ISS) captured this overhead look at the smoke and ash regurgitated from the erupting volcano Mt. Etna on the island of Sicily, Italy in October 2002. Triggered by a series of earthquakes on October 27, 2002, this eruption was one of Etna's most vigorous in years. This image shows the ash plume curving out toward the horizon. The lighter-colored plumes down slope and north of the summit seen in this frame are produced by forest fires set by flowing lava. At an elevation of 10,990 feet (3,350 m), the summit of the Mt. Etna volcano, one of the most active and most studied volcanoes in the world, has been active for a half-million years and has erupted hundreds of times in recorded history.

Earth Science

NASA Image and Video Library

2002-10-30

Expedition Five crew members aboard the International Space Station (ISS) captured this overhead look at the smoke and ash regurgitated from the erupting volcano Mt. Etna on the island of Sicily, Italy in October 2002. Triggered by a series of earthquakes on October 27, 2002, this eruption was one of Etna's most vigorous in years. This image shows the ash plume curving out toward the horizon. The lighter-colored plumes down slope and north of the summit seen in this frame are produced by forest fires set by flowing lava. At an elevation of 10,990 feet (3,350 m), the summit of the Mt. Etna volcano, one of the most active and most studied volcanoes in the world, has been active for a half-million years and has erupted hundreds of times in recorded history.

Emerald ash borer aftermath forests: The dynamics of ash mortality and the responses of other plant species

Treesearch

Kathleen S. Knight; Daniel A. Herms; John Cardina; Robert Long; Joanne Rebbeck; Kamal J.K. Gandhi; Annemarie Smith; Wendy S. Klooster; Catherine P. Herms; Alejandro A. Royo

2010-01-01

The effects of emerald ash borer (EAB) (Agrilus planipennis) on forest ecosystems are being studied through a collaborative research program involving the U.S. Forest Service's Northern Research Station and The Ohio State University. We are monitoring the decline and mortality of >4,500 ash trees and saplings, EAB population density, changes...

Ash, the emerald ash borer, and private forest land management

Treesearch

Tom Crowe

2010-01-01

Forest management through emerald ash borer (EAB) will be a dynamic process that will change based on the best information available at the time. Management decisions will depend on the anticipated time of EAB arrival; the diameter and number of ash present in the forest stand; the diameter and number of other desirable and undesirable species present in the stand (...

Ecological and Topographic Features of Volcanic Ash-Influenced Forest Soils

Treesearch

Mark Kimsey; Brian Gardner; Alan Busacca

2007-01-01

Volcanic ash distribution and thickness were determined for a forested region of north-central Idaho. Mean ash thickness and multiple linear regression analyses were used to model the effect of environmental variables on ash thickness. Slope and slope curvature relationships with volcanic ash thickness varied on a local spatial scale across the study area. Ash...

Does forest community structure influence susceptibility and response to emerald ash borer?

Treesearch

Annemarie Smith; Daniel A. Herms; Robert P. Long

2005-01-01

The ability of invasive species to invade native landscapes may be influenced by community composition. Emerald ash borer (Agrilus planipennis) has already caused considerable mortality of ash in southeast Michigan forests and is now invading forests in northwest Ohio.

Recovery dynamics of evapotranspiration, flow, sediment and nutrients following severe wildfire in eucalypt forests

NASA Astrophysics Data System (ADS)

Lane, P. N.; Sheridan, G. J.; Nyman, P.; Nolan, R.; Nokse, P. J.

2013-12-01

Wildfire is a particularly significant disturbance event in forested landscapes. Around 40,000 km2 of largely forested land has been burnt in south eastern Australia in the past decade. Fire effects on erosion and water quality have been widely reported and studied in many environments, but nutrient dynamics and evapotranspiration (ET) and streamflow are also of significant concern or interest. However the hydrologic response and recovery trajectories of the majority of eucalypt forests has been poorly known. Likewise, the coupling of ET response with sediment and nutrient dynamics has not been explored widely. Our research over the past decade into sediment, nutrients and ET/flow dynamics in differing forest types has led to new insights into this resilience/recovery question in eucalypt forests. This research has encompassed scales from the point to large catchment, identified the driving processes, and led to models that deal with discrete events and risk/probability frameworks. Broadly, we suggest there are two distinct 'sets' of responses and recovery trajectories depending on forest type. (1) wet eucalypt stands of E. regnans and E. delegatensis and associated 'ash' stands; and (2) the drier 'mixed-species' forests. The hydrologic responses of (1) may be summarized as: (i) Widespread mortality of trees exposed to moderate-hot fire, leading to dense single-age regeneration. ET is suppressed for 1-3 years, then increases to exceed that of a stands > 30 years old, with a concomitant inverse effect on flow. This recovery trajectory may play out until forests reach maturity (~100 years) or are re-burnt (ii) Sediment and nutrients (P and N principally) exports can increase by 1-2 orders of magnitude, but export rates recover with 2 years of the fire. Erosion processes are largely non-rill. Water quality issues (per event) are relatively short term (days) For case (2): (i) These stands are fire-resistant and show low (~10 %) rates of mortality. Leaf are recovery (and hence ET) is via epicormic leaves and seedling recruitment. ET response appears to be related to fire severity, with moderate severities producing higher ET rates for some years following leaf recovery. However ecological responses indicate theories of hydrologic equilibrium fit these forests and pre-fire ET rates are likely to recover within 5-10 years. (ii) Changes to peak flow can occur, but are scale-dependent, with only small convective storms cells likely to produce flood flows, and recovery likely within 2 years (iii) Erosion can be by both rill and non-rill processes, and may also be in form of debris flows (DF) in steeper topography. Debris flows produce increased loads x orders of magnitude, and can cause water quality issues on the scale of weeks or months. The key factors (aside from topography and background sediment supply) in rainfall return interval and water repellency/infiltration dynamics mean the time domain for DF is about 2 years. Although the impacts of discrete fire events are relatively short for most disturbance issues, fire return intervals and intensities may have longer term consequences. Higher frequency fires combined with a drying climate may result in less resilient forests systems with changed hydrologic characteristics. An example is re-seeding forests re-burnt before seed can develop, with consequent ET changes.

Wet-dry cycles effect on ash water repellency. A laboratory experiment.

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerdà, Artemi; Oliva, Marc; Mataix, Jorge; Jordán, Antonio

2014-05-01

In the immediate period after the fire, the ash layer has a strong influence on soil hydrological processes, as runoff, infiltration and erosion. Ash is very dynamic in the space and time. Until the first rainfall periods, ash is (re)distributed by the wind. After it can cover the soil surface, infiltrate or transported to other areas by water transport (Pereira et al., 2013a, b). This will have strong implications on nutrient redistribution and vegetation recovery. Ash layer may affect soil water repellency in different ways, depending on fire severity, soil properties and vegetation. Ash produced at low temperatures after low-severity burning is usually hydrophobic (Bodi et al., 2011, 2012). Wet-dry cycles have implications on ash physical and chemical properties, changing their effects in space and time. The aim of this study is to analyse the effects of fire temperature and severity on ash water repellency. Pinus sylvestris needles were collected in a Lithuania forest in Dzukija National Park (53º 54' N and 24º 22' E), transported to laboratory and washed with deionized water to remove soil particles and other residues. Needle samples were dried during 24 hours and exposed to different temperatures: 200, 300, 400 and 500 ºC, during 2 hours. Ash colour was analysed according to the Munsell Soil Color charts. Ash was black (10 YR 2/1) at 200 ºC, very dark grey (10YR 3/1) at 300 ºC, gray (10YR 5/1) at 400 ºC and light gray (10YR 7/1) at 500 ºC. Ten samples of ash released after each treatment were placed in plastic dishes (50 mm in diameter) in an amount enough to form a 5 mm thick layer, and ash water repellency was measured according to the Water Drop Penetration Test. Later, ash was carefully wetted with 15 ml of deionized water and placed in an oven during 4 days (96 hours), as in Bodí et al. (2012). This procedure was repeated 5 times in order to observe the effects of wet-dry cycles in ash water repellency. The results showed significant differences among wet-dry cycles (Chi Sqr = 184.13 p <0.001) and among temperatures, immediately after treatments (Kruskal-Wallis test: H = 13.64, p<0.01) and after first wet-dry cycle (Kruskal-Wallis test: H =13.85 p<0.01). In the second (Kruskal-Wallis test: =5.80, p >0.05), third (Kruskal-Wallis test: H =3.07, p>0.05), fourth (Kruskal-Wallis test: H=0.75, p>0.05) and fifth (Kruskal-Wallis test: H =0.199, p<0.05) wet-dry cycles, ash water repellency did not show significant differences. After wetting, ash water repellency decreased substantially in the first cycle. These results suggest that wet-dry cycles have important impacts in the reduction of ash water repellency. Nevertheless, this reduction at least in the first cycle is different according to the temperature/severity. Black ash (200 ºC) water repellency was significantly higher than the other temperatures/severities. Further research will be carried out using burned soils and different species. References Bodi, M.B., Doerr, S., Cerda, A., Mataix-Solera, J. (2012) Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma, 161, 14-23, 2011. DOI: 10.1016/j.geoderma.2012.01.006. Bodí, M.B., Mataix-Solera, J., Doerr, S.H., Cerdà, A. (2011). The wettability of ash from burned vegetation and its relationship to Mediterranean plant species type, burn severity and total organic carbon content. Geoderma 160, 599-607. DOI:10.1016/j.geoderma.2010.11.009. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2013a) Modelling the impacts of wildfire on ash thickness in a short-term period, Land Degradation and Development. DOI: 10.1002/ldr.2195. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Jordan, A. Burguet, M. (2013b) Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania, Solid Earth, 4, 153-165. DOI: 10.5194/se-4-153-2013.

Modelling soil sodium and potassium adsorption ratio (SPAR) in the immediate period after a grassland fire in Lithuania.

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Cerda, Artemi; Misiūnė, Ieva

2015-04-01

The soil sodium and potassium adsorption ratio (SPAR) is an index that measures the amount of sodium and potassium adsorbed onto clay and organic matter surfaces, in relation to calcium and magnesium. Assess the potential of soil dispersion or flocculation, a process which has implication in soil hydraulic properties and erosion (Sarah, 2004). Depending on severity and the type of ash produced, fire can changes in the immediate period the soil nutrient status (Bodi et al. 2014). Ash releases onto soil surface a large amount of cations, due the high pH. Previous works showed that SPAR from ash slurries is higher than solutions produced from litter (Pereira et al., 2014a). Normally the spatial distribution of topsoil nutrients in the immediate period after the fire is very heterogeneous, due to the different impacts of fire. Thus it is important to identify the most accurate interpolation method in order to identify with better precision the impacts of fire on soil properties. The objective of this work is to test several interpolation methods. The study area is located in near Vilnius (Lithuania) at 54° 42' N, 25° 08 E, 158 masl. Four days after the fire it was designed a plot in a burned area with near Vilnius (Lithuania) at 54° 42' N, 25° 08 E, 158 masl. Twenty five samples were collected from the topsoil. The SPAR index was calculated according to the formula: (Na++K+)/(Ca2++Mg2+)1/2 (Sarah, 2004). Data followed the normal distribution, thus no transformation was required previous to data modelling. Several well know interpolation models were tested, as Inverse Distance to a Weight (IDW) with the power of 1, 2, 3 and 4, Radial Basis Functions (RBF), Inverse Multiquadratic (IMT), Multilog (MTG), Multiquadratic (MTQ), Natural Cubic Spline (NCS) and Thin Plate Spline (TPS) and Local Polynomial (LP) with the power of 1 and 2 and Ordinary Kriging. The best interpolator was the one which had the lowest Root Mean Square Error (RMSE) (Pereira et al., 2014b). The results showed that on average, SPAR index was 0.85, with a minimum of 0.18, a maximum of 1.55, a standard deviation of 0.38 and a coefficient of variation of 44.70%. No previous works were carried out on fire-affected soils, however comparing it to ash slurries obtained from previous works (Pereira et al., 2014a), the values were higher. Among all the interpolation methods tested, the most accurate was IDW 1 (RMSE=0.393), and the less precise NCS (RMSE=0.542). This shows that data distribution is highly variable in space, since IDW methods are better interpolators for data irregularly distributed. The high spatial variability distribution of SPAR is very likely to affect soil hydraulic properties and plant recuperation in the immediate period after the fire. More research is needed to identify the SPAR spatio-temporal impacts of fire on soil. Acknowledgments POSTFIRE (Soil quality, erosion control and plant cover recovery under different post-fire management scenarios, CGL2013-47862-C2-1-R), funded by the Spanish Ministry of Economy and Competitiveness; Fuegored; RECARE (Preventing and Remediating Degradation of Soils in Europe Through Land Care, FP7-ENV-2013-TWO STAGE), funded by the European Commission; and for the COST action ES1306 (Connecting European connectivity research). References Bodi, M., Martin, D.A., Santin, C., Balfour, V., Doerr, S.H., Pereira, P., Cerda, A., Mataix-Solera, J. (2014) Wildland fire ash: production, composition and eco-hyro-geomorphic effects. Earth-Science Reviews, 130, 103-127. Pereira, P., Úbeda, X., Martin, D., Mataix-Solera, J., Cerdà, A., Burguet, M. (2014a) Wildfire effects on extractable elements in ash from Pinus Pinaster forest in Portugal. Hydrological Processes, 28, 3681-3690. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2014) Modelling the impacts of wildfire on ash thickness in the immediate period after the fire. Land Degradation and Development. DOI: 10.1002/ldr.2195 Sarah, P. (2004) Soil sodium and potassium adsorption ratio along a Mediterranean-arid transect. Journal of Arid Environments, 59, 731-741.

Short-term nitrogen losses by overland flow in a recently burnt forest area in north-central Portugal: A study at micro-plot scale.

PubMed

Ferreira, R V; Serpa, D; Machado, A I; Rodríguez-Blanco, M L; Santos, L F; Taboada-Castro, M T; Cerqueira, M A; Keizer, J J

2016-12-01

Over the past decades, wildfires have affected extensive areas of the Mediterranean region with negative impacts on the environment. Most of the studies on fire-affected areas have focused on sediment losses by overland flow, whereas few have addressed post-fire nutrient export. The present study aimed to address this research gap by assessing nitrogen (nitrate and total nitrogen) losses by overland flow in a recently burnt area in north-central Portugal. To this end, three burnt slopes were selected for their contrasting forest types (eucalypt vs. pine) and parent materials (granite vs. schist). The selected study sites were a eucalypt site on granite (BEG), a eucalypt site on schist (BES) and a maritime pine site on schist (BPS). Overland flow samples were collected during the first six months after the wildfire on a 1- to 2-weekly basis, after which this study had to be cancelled due to bench terracing of some of the sites. A peak in total nitrogen concentrations was observed in burnt areas immediately after the first post-fire rainfall event as a response to the erosion of the N-enriched ash layer. After this initial peak, smaller peaks were observed throughout the study period, mainly as a response to overland flow and/or erosion events. Nitrogen export differed strikingly between the two types of forests on schist, being higher at the eucalypt than at the pine site, due to the lack of a protective soil layer. Parent material did not play an important role on nitrogen export by overland flow since no significant differences were found between the eucalypt sites on granite and schist. The present study provides some insight into the differences in post-fire soil fertility losses between forest types and parent materials in the Mediterranean region, which is crucial information for defining post-fire land management measures to reduce soil degradation. Copyright © 2015 Elsevier B.V. All rights reserved.

Large-Scale Forest Fires and Resulting Alterations to the Hydrologic Cycle in the Western U.S

NASA Astrophysics Data System (ADS)

Carr, J.; White, A. B.; Thomson, B.

2012-12-01

Recent changes in climate have resulted in a decrease in precipitation and snowpack amounts and increased temperatures in the western United States. Drier and warmer conditions coupled with forest management issues have led to an increase in the frequency and size of forest fires. The 2000 Cerro Grande fire in Los Alamos, New Mexico burned over 43,000 acres and 200 structures. Eleven years later, the Las Conchas fire burned over 156,000 acres and 100 structures, including areas previously burned in 2000, and was considered the largest fire in New Mexico's history. Both fires burned ponderosa, juniper, piñon and mixed conifer forests, resulting in dramatic decreases in vegetation, changes to surface soils, and alterations to the hydrologic cycle (decreased evapotranspiration, decreased infiltration, increased runoff volume and peak discharge, and decreased time to peak discharge) in surrounding watersheds. Burned Area Emergency Response (BAER) teams need to determine the flash-flood danger quickly in order to protect residents, fire-fighters, BAER-team field personnel, and property at risk. The USGS developed an analytical method for predicting post-fire peak discharges using data collected from eight different fires throughout the western United States. We use this method to predict peak discharge in Los Alamos watersheds post-Cerro Grande and post-Las Conchas, then compare predicted to measured peak discharge. We will evaluate the effectiveness of the three methodology levels presented by the USGS, which include varying levels of data input and processing. We expect the peak discharges to be similar in magnitude; however, we will also investigate different influential factors such as burn severity, soil type, vegetation type and density, ecological connectivity, topography, pre- and post-fire weather conditions, etc., as they relate to the fires and the results seen from the measured versus the analytical method. Determining the relative influence of these factors may be important in establishing the comprehensive nature of the methodology. The frequency of large, intense "mega-fires" are predicted to increase, thus there is a potential for more post-fire flood damage and more surface water resources to be altered due to water quality issues. For example, the Whitewater-Baldy Complex fire became the largest fire in New Mexico's history one year after the Las Conchas fire by burning almost 300,000 acres in the Gila National Forest in southern New Mexico, the Little Bear fire in 2012 forced the closure of Alto Reservoir for the foreseeable future due to ash and debris, and the Las Conchas fire forced several surface water treatment facilities serving Santa Fe and Albuquerque to shut down. As these fires become more frequent, there is a potential that less surface water will be available and more groundwater will be pumped for human and agricultural use in the western U.S., where water scarcity is already a pressing problem. Understanding how these fires alter the hydrologic cycle is critical to water policy and planning and this research will help advance that understanding.

Recycling of Sustainable Co-Firing Fly Ashes as an Alkali Activator for GGBS in Blended Cements

PubMed Central

Wu, Yann-Hwang; Huang, Ran; Tsai, Chia-Jung; Lin, Wei-Ting

2015-01-01

This study investigates the feasibility of co-firing fly ashes from different boilers, circulating fluidized beds (CFB) or stokers as a sustainable material in alkali activators for ground granulated blast-furnace slag (GGBS). The mixture ratio of GGBS and co-firing fly ashes is 1:1 by weight. The results indicate that only CF fly ash of CFB boilers can effectively stimulate the potential characteristics of GGBS and provide strength as an alkali activator. CF fly ash consists of CaO3 (48.5%), SiO2 (21.1%), Al2O3 (13.8%), SO3 (10.06%), Fe2O3 (2.25%) and others (4.29%). SA fly ash consists of Al2O3 (19.7%), SiO2 (36.3%), Fe2O3 (28.4%) and others (15.6%). SB fly ash consists of Al2O3 (15%), SiO2 (25.4%), Zn (20.6%), SO3 (10.9%), Fe2O3 (8.78%) and others (19.32%). The mixtures of SA fly ash and SB fly ash with GGBS, respectively, were damaged in the compressive strength test during seven days of curing. However, the built up strength of the CF fly ash and GGBS mixture can only be maintained for 7–14 days, and the compressive strength achieves 70% of that of a controlled group (cement in hardening cement paste). The strength of blended CF fly ash and GGBS started to decrease after 28 days, and the phenomenon of ettrigite was investigated due to the high levels of sulfur content. The CaO content in sustainable co-firing fly ashes must be higher than a certain percentage in reacting GGBS to ensure the strength of blended cements. PMID:28787970

Is fire a long term sink or source of atmospheric carbon? A comprehensive evaluation of a boreal forest fire

NASA Astrophysics Data System (ADS)

Santin, C.; Doerr, S. H.; Preston, C.; Bryant, R.

2012-12-01

Fires lead to a rapid release of carbon (C) from forest and other fire-prone ecosystems, emitting important quantities of C to the atmosphere. Every year 300-600 Mill. ha burn around the globe, generating CO2 emissions equivalent to half of the current annual global from fossil fuel combustion. Over the longer-term vegetation fires are widely considered as 'net zero Carbon (C) emission events', because C emissions from fires, excluding those associated with deforestation, are balanced by C uptake by regenerating vegetation. This 'zero C emission' scenario, however, may be flawed, as it does not consider the role of pyrogenic C (PyC). During fire, some of the fuel is transformed into PyC (i.e. charcoal, black C, soot), which is characterized by an enhanced recalcitrance and a longer mean residence time in the environment than its 'fresh' precursors. Therefore, after complete regeneration of the vegetation, the PyC generated represents an additional longer-term C pool and, hence, recurring fire-regrowth cycles could be considered as a 'net sink of atmospheric C'. To test the validity of this hypothesis, and to estimate how quantitatively important this PyC pool might be, accurate data on PyC production with respect to the fuel combusted are needed. Unfortunately, detailed quantification of fuel prior to fire is normally only available for prescribed and experimental fires, which are usually of low-intensity and therefore not representative of higher-intensity wildfires. Furthermore, what little data is available is usually based on only a specific fraction of the PyC present following burning rather than the whole range of PyC products and stores (i.e. PyC in soil, ash, downed wood and standing vegetation). The FireSmart project (Ft. Providence, NWT, Canada, June 2012) provided the ideal framework to address this research gap. This experimental fire reproduced wildfire conditions in boreal forest, i.e. stand-replacing crown fire and, at the same time, allowed i) pre-fire fuel assessment, ii) fire behaviour monitoring and iii) immediate post-fire fuel and PyC inventory. Before the fire, fuel characteristics were established and the site was instrumented with auto-logging thermocouples to provide temperature-duration profiles during burning. Also, different types of PyC were placed on the ground to determine PyC loss during the fire. Immediately after fire, the various post-burn PyC products and stores were sampled. Total PyC was quantified and the chemical recalcitrance of the different PyC forms found was determined. The results obtained will be discussed in the context of PyC production, and its different forms and quantities, with respect to (i) fire characteristics and fuel consumed, and (ii) the long term carbon balance in this boreal forest environment for recurring fire-regrowth cycles under current and predicted future climatic conditions.

Production of thermal insulation blocks from bottom ash of fluidized bed combustion system.

PubMed

Mandal, A K; Sinha, O P

2017-08-01

The issues of disposal and environmental problems are increased by the generation of bottom ash from the thermal power plants day by day; hence, its recycling is required. The present study aimed to make thermal insulation blocks using as raw material bottom ash and iron ore slime as a binder and to characterize their engineering properties. Two different fineness values of bottom ash were considered with varying amounts of iron ore slime (0-10%) to make the blocks. Blocks were dried followed by firing at 1000, 1100 and 1200°C, respectively. Cold crushing strength, density and thermal conductivity of these fired blocks showed increasing behaviour with firing temperature, fineness of bottom ash and iron ore slime content. In contrast, a reverse trend was observed in the case of porosity. With increasing firing temperature, the formation of lower melting phases like iron silicate followed by iron aluminium silicate was observed, which imparts the strength inside the blocks. The coarser particles of bottom ash increase the interparticle spaces, which enhances the apparent porosity, resulting in higher thermal insulation property in the blocks. Blocks having better thermal insulation property could be possible to make effectively from coarse bottom ash by adding iron ore slime as a binder.

Wildland fire ash: Production, composition and eco-hydro-geomorphic effects

USGS Publications Warehouse

Bodi, Merche B.; Martin, Deborah; Balfour, Victoria N.; Santin, Cristina; Doerr, Stefan H.; Pereira, Paulo; Cerda, Artemi; Mataix-Solera, Jorge

2014-01-01

Fire transforms fuels (i.e. biomass, necromass, soil organic matter) into materials with different chemical and physical properties. One of these materials is ash, which is the particulate residue remaining or deposited on the ground that consists of mineral materials and charred organic components. The quantity and characteristics of ash produced during a wildland fire depend mainly on (1) the total burned fuel (i.e. fuel load), (2) fuel type and (3) its combustion completeness. For a given fuel load and type, a higher combustion completeness will reduce the ash organic carbon content, increasing the relative mineral content, and hence reducing total mass of ash produced. The homogeneity and thickness of the ash layer can vary substantially in space and time and reported average thicknesses range from close to 0 to 50 mm. Ash is a highly mobile material that, after its deposition, may be incorporated into the soil profile, redistributed or removed from a burned site within days or weeks by wind and water erosion to surface depressions, footslopes, streams, lakes, reservoirs and, potentially, into marine deposits.Research on the composition, properties and effects of ash on the burned ecosystem has been conducted on material collected in the field after wildland and prescribed fires as well as on material produced in the laboratory. At low combustion completeness (typically T < 450 °C), ash is organic-rich, with organic carbon as the main component. At high combustion completeness (T > 450 °C), most organic carbon is volatized and the remaining mineral ash has elevated pH when in solution. It is composed mainly of calcium, magnesium, sodium, potassium, silicon and phosphorous in the form of inorganic carbonates, whereas at T > 580 °C the most common forms are oxides. Ash produced under lower combustion completeness is usually darker, coarser, and less dense and has a higher saturated hydraulic conductivity than ash with higher combustion completeness, although physical reactions with CO2 and when moistened produce further changes in ash characteristics.As a new material present after a wildland fire, ash can have profound effects on ecosystems. It affects biogeochemical cycles, including the C cycle, not only within the burned area, but also globally. Ash incorporated into the soil increases temporarily soil pH and nutrient pools and changes physical properties such as albedo, soil texture and hydraulic properties including water repellency. Ash modifies soil hydrologic behavior by creating a two-layer system: the soil and the ash layer, which can function in different ways depending on (1) ash depth and type, (2) soil type and (3) rainfall characteristics. Key parameters are the ash's water holding capacity, hydraulic conductivity and its potential to clog soil pores. Runoff from burned areas carries soluble nutrients contained in ash, which can lead to problems for potable water supplies. Ash deposition also stimulates soil microbial activity and vegetation growth.Further work is needed to (1) standardize methods for investigating ash and its effects on the ecosystem, (2) characterize ash properties for specific ecosystems and wildland fire types, (3) determine the effects of ash on human and ecosystem health, especially when transported by wind or water, (4) investigate ash's controls on water and soil losses at slope and catchment scales, (5) examine its role in the C cycle, and (6) study its redistribution and fate in the environment.

EAB induced tree mortality impacts ecosystem respiration and tree water use in an experimental forest

Treesearch

Charles E. Flower; Douglas J. Lynch; Kathleen S. Knight; Miquel A. Gonzales-Meler

2011-01-01

The invasive emerald ash borer (Agrilus planipennis Fairmaire, EAB) has been spreading across the forest landscape of the Midwest resulting in the rapid decline of ash trees (Fraxinus spp.). Ash trees represent a dominant riparian species in temperate deciduous forests of the Eastern United States (USDA FIA Database). Prior...

Canopy treatment influences growth of replacement tree species in Fraxinus nigra forests threatened by the emerald ash borer in Minnesota, USA

Treesearch

Christopher E. Looney; Anthony W. D' Amato; Brian J. Palik; Robert A. Slesak

2017-01-01

Fraxinus nigra Marsh. (black ash), a dominant tree species of wetland forests in northern Minnesota, USA, is imperiled by the invasive insect emerald ash borer (EAB; Agrilus planipennis Fairmaire, 1888). Regeneration of associated tree species is generally low in F. nigra forests and could be impacted...

Emerald Ash Borer: Invasion of the Urban Forest and the Threat to North America's Ash Resource

Treesearch

Therese M. Poland; Deborah G. McCullough

2006-01-01

The emerald ash borer (EAB), a phloem-feeding beetle native to Asia, was discovered killing ash trees in southeastern Michigan and Windsor, Ontario, in 2002. Like several other invasive forest pests, the EAB likely was introduced and became established in a highly urbanized setting, facilitated by international trade and abundant hosts. Up to 15 million ash trees in...

Seasonal Variations in Ash Content of Some Michigan Forest Floor Fuels

Treesearch

Robert M. Loomis

1982-01-01

Samples from the forest floor litter layer were collected seasonally from under medium to fully stocked larger sapling to sawtimber stands in Lower Michigan to study seasonal ash content changes. The total ash and silica-free ash content of tree foliage in the upper part of the litter layer differed little from season to season. Differences in ash content due to...

Recent advances towards an integrated assessment of wildfire effects in forest plantations in Portugal

NASA Astrophysics Data System (ADS)

Keizer, Jan Jacob; Abrantes, Nelson; Nunes, João Pedro; Caetano, Ana; Campos, Isabel; Faria, Silvia; Gonzaléz-Pelayo, Oscar; Hoogerwerf, Annelou; Malvar, Maruxa; Martins, Martinho; Methorst, Michael; Oliveira, Bruna; Prats, Sergio; Puga, João; Ré, Ana; Silva, Flávio; Serpa, Dalila; Varela, Marifé; Verheijen, Frank; Vieira, Diana

2017-04-01

Wildfires have been a common phenomenon during the warm and dry summers in Portugal over the past decades, having affected, on average, some 100.000 ha per year and, in extremis, roughly 450.000 ha in 2005. Existing forecasts do not suggest major improvements in the next few decades, due to likely future climate conditions that are to be even more propitious to fire ignition and spreading and, arguably, the nature of the underlying causes that are deeply-rooted in Portugal's present-day society as well as in its rural and forest policies. Since the dramatic wildfire summers of 2003 and 2005, the earth surface processes (esp) team has been working towards its ultimate goal of a model-based tool in support of post-fire land management which would allow identifying and mapping areas with high erosion risk after fire and post-fire land management operations and would allow predicting the effectiveness of emergency stabilization measures to reduce this risk. Although this tool is still in its infancy, in recent years the esp team has made some progress with modelling post-fire runoff and erosion, and its reduction by mulching with forest logging residues, with a special focus on soil water repellency in the adaptation of existing models to recently burned conditions (Vieira et al., 2014; Nunes et al., 2016; Van Eck et al., 2016). This modelling work will be addressed in detail by another presentation at this EGU conference (Nunes et al., 2017). The esp team does, however, dispose of a wealth of field data to further its modelling efforts, not just at the plot to field scale but also at the scale of small experimental catchments (typically less than 1 km2), not just for single fires but also for recurrent fires, not just for "doing nothing" and typical post-fire forestry operations (logging, wood extraction, bench terracing) but also for various soil conservation measures (hydro-mulching, forest logging residues mulching, shrub barriers), and not just for runoff and sediment losses but also for organic matter/carbon losses, nutrient losses and pollutant export (PAHs and metals). Arguably, however, the most relevant advances that the esp team has been making in the past few years concern the following three topics: (i) the evolution of PAH and metal contents of ash and topsoil layers with time-since-fire (Campos et al., 2016); (ii) the eco-toxicological effects of post-fire runoff on aquatic organisms, especially through in-situ assays (Ré at al., 2017); (iii) mid-term effects of forest residue mulching on soil (fertility) losses as well as vegetation and soil physical, chemical and biological properties (Campos et al., 2016; Prats et al., 2016, Puga et al., in press) . Besides these three topics, the present presentation will address one topic of very recent nature (since summer 2016) and one topic of future work (from summer 2017 onwards), i.e. (iv) pre- vs. post-fire catchment behaviour and (v) post-fire carbon fluxes at the point to field scale, respectively. References Campos I., Abrantes N., Keizer J.J., Vale C., Pereira P., 2016. Major and trace elements in soils and ashes of eucalypt and pine forest plantations in Portugal following a wildfire. Science of the Total Environment 572, 1363-1376 Nunes J.P, Malvar M., Benali A.A., Rial M.E.R., Keizer J.J., 2016. A simple water balance model adapted for soil water repellency: application on Portuguese burned and unburned eucalypt stands. Hydrological Processes 30, 463-478. Nunes J.P, Vieira D., Keizer J.J., 2016. Comparing simple and complex approaches to simulate the impacts of soil water repellency on runoff and erosion in burnt Mediterranean forest slopes. EGU2017, session SSS2.22/HS9.12/NH9.24. Prats S.A., Wagenbrenner J., Malvar MC., Martins MAS., Keizer JJ., 2016. Mid-term effectiveness of mulching-based treatments in central Portugal. Science of the Total Environment 573, 1242-1254. Puga J.R.L., Abrantes N.J.C., de Oliveira M.J.S., Vieira D.C.S., Faria S.R., Gonçalves F., Keizer J.J., 2017 (in press). Long-term impacts of post-fire mulching on ground-dwelling arthropod communities in a eucalypt plantation. Land Degradation and Development; DOI: 10.1002/ldr.2583. Ré A., Saraiva M., Puga J., Campos I., Pereira J.L., Keizer J-. ,Gonçalves F., Abrantes N. (2017). Assessing off-site impacts of wildfires on aquatic organisms using in-situ assays. EGU2017, session SSS2.22/HS9.12/NH9.24. van Eck C. M., Nunes J. P., Vieira D. C. S., Keesstra S., Keizer J. J.. 2016. Physically-based modelling of the post-fire runoff response of a forest catchment in central Portugal: using field vs. RS-based estimates of vegetation recovery. Land Degradation and Development 27, 1535-1544. Vieira D.C.S., Prats S.A., Nunes J.P., Shakesby R.A., Coelho C.O.A., Keizer J.J, 2014. Modelling runoff and erosion, and their mitigation, in burned Portuguese forest using the revised Morgan-Morgan-Finney model. Forest Ecology and Management 314, 150-165.

Biological effects of wood ash application to forest and aquatic ecosystems.

PubMed

Aronsson, K Andreas; Ekelund, Nils G A

2004-01-01

The present review aims to summarize current knowledge in the topic of wood ash application to boreal forest and aquatic ecosystems, and the different effects derived from these actions. Much research has been conducted regarding the effects of wood ash application on forest growth. Present studies show that, generally speaking, forest growth can be increased on wood ash-ameliorated peatland rich in nitrogen. On mineral soils, however, no change or even decreased growth have been reported. The effects on ground vegetation are not very clear, as well as the effects on fungi, soil microbes, and soil-decomposing animals. The discrepancies between different studies are for the most part explained by abiotic factors such as variation in fertility among sites, different degrees of stabilization, and wood ash dosage used, and different time scales among different studies. The lack of knowledge in the field of aquatic ecosystems and their response to ash application is an important issue for future research. The few studies conducted have mainly considered changes in water chemistry. The biotoxic effects of ash application can roughly be divided into two categories: primary and secondary. Among the primary effects is toxicity deriving from compounds in the wood ash and cadmium is probably the worst among these. The secondary effects of wood ash are generally due to its alkaline capacity and a release of ions into the soil and soil water, and finally, watercourses and lakes. Given current knowledge, we would recommend site- and wood ash-specific application practices, rather than broad and general guidelines for wood ash application to forests.

How fast will trees die? A transition matrix model of ash decline in forest stands infested by emerald ash borer

Treesearch

Kathleen S. Knight; Robert P. Long; Joanne Rebbeck; Annemarie Smith; Kamal Gandhi; Daniel A. Herms

2008-01-01

We recorded Fraxinus spp. tree health and other forest stand characteristics for 68 plots in 21 EAB-infested forest stands in Michigan and Ohio in 2005 and 2007. Fraxinus spp. were a dominant component of these stands, with more than 900 ash trees (including Fraxinus americana, Fraxinus pennsylvanica, Fraxinus profunda...

Planning for and implementing an emerald ash borer-induced forest restoration program in municipal woodlands in Oakville, Ontario

Treesearch

Peter A. Williams; Candace. Karandiuk

2017-01-01

Oakville is an urban municipality with 846 ha of woodland. Management priorities are to maintain forest health, environmental health, and safety; wood production is a minor objective. The town developed a comprehensive strategy to plan for emerald ash borer (EAB; Agrilus planipennis) induced ash mortality and forest restoration. Oakville has begun...

Sap flow of black ash in wetland forests of northern Minnesota, USA: Hydrologic implications of tree mortality due to emerald ash borer

Treesearch

Andrew C. Telander; Robert A. Slesak; Anthony W. D' Amato; Brian J. Palik; Kenneth N. Brooks; Christian F. Lenhart

2015-01-01

Black ash (Fraxinus nigra) mortality caused by the invasive emerald ash borer (EAB) is of concern to land managers in the upper Great Lakes region, given the large areas of ash-dominated forest and potential alteration of wetland hydrology following loss of this foundation tree species. The importance of changes in evapotranspiration (ET) following...

Predicting the ability to produce emerald ash borer: a comparison of riparian and upland ash forests in southern lower Michigan

Treesearch

Susan J. Crocker; Deborah G. McCullough; Nathan W. Siegert

2009-01-01

Concern for the future of ash trees in the United States has risen since the 2002 discovery of emerald ash borer (EAB) (Agrilus planipennis Fairmaire) in southeastern Michigan. The ability of ash forests in the Southern Lower Peninsula of Michigan to produce EAB was compared by physiographic class and stand size. Results showed that EAB production...

Sulfur-bearing coatings on fly ash from a coal-fired power plant: Composition, origin, and influence on ash alteration

USGS Publications Warehouse

Fishman, N.S.; Rice, C.A.; Breit, G.N.; Johnson, R.D.

1999-01-01

Fly ash samples collected from two locations in the exhaust stream of a coal-fired power plant differ markedly with respect to the abundance of thin (???0.1 ??m) sulfur-rich surface coatings that are observable by scanning electron microscopy. The coatings, tentatively identified as an aluminum-potassium-sulfate phase, probably form upon reaction between condensed sulfuric acid aerosols and glass surfaces, and are preferentially concentrated on ash exposed to exhaust stream gases for longer. The coatings are highly soluble and if sufficiently abundant, can impart an acidic pH to solutions initially in contact with ash. These observations suggest that proposals for ash use and predictions of ash behavior during disposal should consider the transient, acid-generating potential of some ash fractions and the possible effects on initial ash leachability and alteration. ?? 1998 Elsevier Science Ltd.

Predicting hydrological and erosional risks in fire-affected watersheds: recent advances and research gaps

NASA Astrophysics Data System (ADS)

Nunes, João Pedro; Keizer, Jan Jacob

2017-04-01

Models can be invaluable tools to assess and manage the impacts of forest fires on hydrological and erosion processes. Immediately after fires, models can be used to identify priority areas for post-fire interventions or assess the risks of flooding and downstream contamination. In the long term, models can be used to evaluate the long-term implications of a fire regime for soil protection, surface water quality and potential management risks, or determine how changes to fire regimes, caused e.g. by climate change, can impact soil and water quality. However, several challenges make post-fire modelling particularly difficult: • Fires change vegetation cover and properties, such as by changing soil water repellency or by adding an ash layer over the soil; these processes, however are not described in currently used models, so that existing models need to be modified and tested. • Vegetation and soils recover with time since fire, changing important model parameters, so that the recovery processes themselves also need to be simulated, including the role of post-fire interventions. • During the window of vegetation and soil disturbance, particular weather conditions, such as the occurrence of severe droughts or extreme rainfall events, can have a large impact on the amount of runoff and erosion produced in burnt areas, so that models that smooth out these peak responses and rather simulate "long-term" average processes are less useful. • While existing models can simulate reasonable well slope-scale runoff generation and associated sediment losses and their catchment-scale routing, few models can accommodate the role of the ash layer or its transport by overland flow, in spite of its importance for soil fertility losses and downstream contamination. This presentation will provide an overview of the importance of post-fire hydrological and erosion modelling as well as of the challenges it faces and of recent efforts made to overcome these challenges. It will illustrate these challenges with two examples: probabilistic approaches to simulate the impact of different vegetation regrowth and post-fire climate combinations on runoff and erosion; and model developments for post-fire soil water repellency with different levels of complexity. It will also present an inventory of the current state-of-the-art and propose future research directions, both on post-fire models themselves and on their integration with other models in large-scale water resource assessment management.

Mapping ash properties using principal components analysis

NASA Astrophysics Data System (ADS)

Pereira, Paulo; Brevik, Eric; Cerda, Artemi; Ubeda, Xavier; Novara, Agata; Francos, Marcos; Rodrigo-Comino, Jesus; Bogunovic, Igor; Khaledian, Yones

2017-04-01

In post-fire environments ash has important benefits for soils, such as protection and source of nutrients, crucial for vegetation recuperation (Jordan et al., 2016; Pereira et al., 2015a; 2016a,b). The thickness and distribution of ash are fundamental aspects for soil protection (Cerdà and Doerr, 2008; Pereira et al., 2015b) and the severity at which was produced is important for the type and amount of elements that is released in soil solution (Bodi et al., 2014). Ash is very mobile material, and it is important were it will be deposited. Until the first rainfalls are is very mobile. After it, bind in the soil surface and is harder to erode. Mapping ash properties in the immediate period after fire is complex, since it is constantly moving (Pereira et al., 2015b). However, is an important task, since according the amount and type of ash produced we can identify the degree of soil protection and the nutrients that will be dissolved. The objective of this work is to apply to map ash properties (CaCO3, pH, and select extractable elements) using a principal component analysis (PCA) in the immediate period after the fire. Four days after the fire we established a grid in a 9x27 m area and took ash samples every 3 meters for a total of 40 sampling points (Pereira et al., 2017). The PCA identified 5 different factors. Factor 1 identified high loadings in electrical conductivity, calcium, and magnesium and negative with aluminum and iron, while Factor 3 had high positive loadings in total phosphorous and silica. Factor 3 showed high positive loadings in sodium and potassium, factor 4 high negative loadings in CaCO3 and pH, and factor 5 high loadings in sodium and potassium. The experimental variograms of the extracted factors showed that the Gaussian model was the most precise to model factor 1, the linear to model factor 2 and the wave hole effect to model factor 3, 4 and 5. The maps produced confirm the patternd observed in the experimental variograms. Factor 1 and 2 maps showed high values in one area of the plot, while factors 3,4 and 5 had a cycled pattern. Using a PCA we resume the information of all dataset and we identify that ash properties have a different distribution in the studied area, that may be attributed to the different fire severities. References Bodi, M., Martin, D.A., Santin, C., Balfour, V., Doerr, S.H., Pereira, P., Cerda, A., Mataix-Solera, J. (2014) Wildland fire ash: production, composition and eco-hydro-geomorphic effects. Earth-Science Reviews, 130, 103-127. Cerdà A, Doerr SH. (2008) The effect of ash and needle cover on surface runoff and erosion in the immediate post-fire period. Catena 74, 256-263. Jordan, A., Zavala, L., Granjed, A.J., Gordillo-Rivero, A.J., Garcia-Moreno, J., Pereira, P., Barcenas-Moreno, G., Celis, R., Jimenez-Compan, E., Alanis, N. Wettability of ash conditions splash erosion and runoff rates in the postfire. Science of the Total Environment, 572, 1261-1268. Pereira, P. Cerdà, A., Úbeda, X., Mataix-Solera, J. Arcenegui, V., Zavala, L. (2015b) Modelling the impacts of wildfire on ash thickness in a short-term period. Land Degradation and Development, 26, 180-192. Pereira, P., Brevik, E., Cerda, A., Ubeda, X., Novara, A., Francos, M., Comino, R., Bogunovic, I., Khaledian, Y. Mapping ash extractable elements using principal component analysis In: Pereira, P., Brevik, E., Munoz-Rojas, M., Miller, B. (eds) Soil mapping and process modelling for sustainable land use management (Elsevier Publishing House) ISBN: 9780128052006 Pereira, P., Cerdà, A., Jordan, A., Zavala, L., Mataix-Solera, J., Arcenegui, V., Misiune, I., Keesstra, S., Novara, A. (2016) Vegetation recovery after a grassland fire in Lithuania. The effects of fire severity, slope position and aspect. Land Degradation and Development, 27, 1523-1534. Pereira, P., Rein, G., Martin, D. Editorial: Past and Present Post-Fire Environments. Science of the Total Environment, 573, 442-436. Pereira, P., Jordan, A., Cerdà, A., Martin, D. Editorial: The role of ash in fire-affected ecosystems. Catena, 135, 337-379.

Chemical and engineering properties of fired bricks containing 50 weight percent of class F fly ash

USGS Publications Warehouse

Chou, I.-Ming; Patel, V.; Laird, C.J.; Ho, K.K.

2001-01-01

The generation of fly ash during coal combustion represents a considerable solid waste disposal problem in the state of Illinois and nationwide. In fact, the majority of the three million tons of fly ash produced from burning Illinois bituminous coals is disposed of in landfills. The purpose of this study was to obtain a preliminary assessment of the technical feasibility of mitigating this solid waste problem by making fired bricks with the large volume of fly ash generated from burning Illinois coals. Test bricks were produced by the extrusion method with increasing amounts (20-50% by weight) of fly ash as a replacement for conventional raw materials. The chemical characteristics and engineering properties of the test bricks produced with and without 50 wt% of fly ash substitutions were analyzed and compared. The properties of the test bricks containing fly ash were at least comparable to, if not better than, those of standard test bricks made without fly ash and met the commercial specifications for fired bricks. The positive results of this study suggest that further study on test bricks with fly ash substitutions of greater than 50wt% is warranted. Successful results could have an important impact in reducing the waste disposal problem related to class F fly ash while providing the brick industry with a new low cost raw material. Copyright ?? 2001 Taylor & Francis.

Investigation of occupational radiation exposures to NORM at an Irish peat-fired power station and potential use of peat fly ash by the construction industry.

PubMed

Organo, C; Lee, E M; Menezes, G; Finch, E C

2005-12-01

Annually, approximately 15% of Ireland's electricity requirement is provided through the combustion of 3 x 10(6) tonnes of peat. While the literature on coal-fired power generation is quite abundant, studies on the peat-fired power generation industry from a radiological point of view are scarce. A study of the largest Irish peat-fired power plant was initiated to review the potential occupational radiation exposures arising from the occurrence of naturally occurring radioactive material (NORM) at different stages of the industrial process and to investigate any radiological health consequences that may arise should peat fly ash be used as a component of building materials. Ambient gamma dose rate measurements, radon measurements, quantification of the occupational exposure from inhalation of airborne particles (personal air sampling) and gamma spectrometry analysis of peat, peat ash and effluent samples from the ash ponds were undertaken. The results indicate that the radiation dose received by any worker involved in the processing of the peat and the handling of the ash resulting from peat combustion does not exceed 150 microSv per annum. Regulatory control of the peat-fired power generation is therefore unnecessary according to the Irish legislation with regards to NORM. The potential use of peat fly ash as a by-product in the building industry was also found to have a negligible radiological impact for construction workers and for members of the public.

Effect of fire residues (ash and char) on microbial activity, respiration and methanogenesis in three subtropical wetland soils

NASA Astrophysics Data System (ADS)

Medvedeff, C.; Hogue, B.; Inglett, P.

2011-12-01

Prescribed fire is a common restoration and maintenance technique in the southern United States. Prescribed burns coupled with frequent natural fires in South Florida can have devastating effects on ecosystem function. To determine the effect fire residues have on carbon biogeochemical cycling litter material was obtained from two restored and one native marl wetland in Everglades National Park and manipulated in a laboratory setting to produce ash and vegetation derived char. Based on vegetation biomass removal pre and post fire (insitu) appropriate aliquots of each fire residue was added to experimental microcosms as a soil amendment. Soil enzymes (β-glucosidase, cellobiohydrolase, phosphatase, bis-phosphate and leucine amino peptidase), aerobic and anaerobic respiration (CO2) potentials, extractable C and methanogenesis were measured over a 25 day period. Regardless of site C enzymes responded to both amendments within 5 days of addition. Similarly amended soil contained more extractable carbon in the reference and one of the restored sites. In the restored sites ash and char inhibited methanogenesis, had no effect on anaerobic CO2 potentials, but stimulated aerobic respiration after ten days. In contrast, within the first ten days phosphatase enzyme activity was lower in the ash treatment when compared to the control treatment and stimulation of aerobic respiration was observed in both treatment soils. After ten days ash stimulated methanogenic processing while suppressing anaerobic CO2 production suggesting methanogens in this ecosystem may be dependant on usable carbon substrates derived from aerobic microbial processing. This study illustrates the variable response of C parameters to complete and incomplete combusted materials produced from both prescribed and natural fires with particular importance to fire adapted ecosystems.

Environmental impact assessment of wood ash utilization in forest road construction and maintenance--A field study.

PubMed

Oburger, Eva; Jäger, Anna; Pasch, Alexander; Dellantonio, Alex; Stampfer, Karl; Wenzel, Walter W

2016-02-15

The ever increasing use of wood material as fuel for green energy production requires innovative, environmentally safe strategies for recycling of the remaining wood ash. Utilizing wood ash in forest road construction and maintenance to improve mechanical stability has been suggested as a feasible recycling option. To investigate the environmental impact of wood ash application in forest road maintenance, a two-year field experiment was conducted at two Austrian forest sites (Kobernausserwald (KO) (soil pH 5.5) and Weyregg (WE) (pH 7.7)) differing in their soil chemical properties. Two different ashes, one produced by grate incineration (GA) and the other by fluidized bed incineration in a mixture with 15 vol% burnt lime (FBA), were incorporated in repeated road sections at a 15:85% (V/V) ash-to-soil rate. Leaching waters from the road body were collected and analyzed for 32 environmentally relevant parameters over two years. Upon termination of the experiment, sub-road soil samples were collected and analyzed for ash-related changes in soil chemistry. Even though a larger number of parameters was affected by the ash application at the alkaline site (WE), we observed the most pronounced initial increases of pH as well as Al, As, Fe, Mn, Ni, Co, Cu, Mo, and NO2(−) concentrations in leachates beneath GA-treated road bodies at Kobernausserwald due to the lower soil buffer capacity at this site. Despite the observed effects our results indicate that, when specific requirements are met (i.e. appropriate ash quality, sufficient soil buffer capacity below the road body, and single time-point ash incorporation within several decades), wood ash application in forest road construction is generally environmentally acceptable.

Effects of fire temperature on the physical and chemical characteristics of the ash from two plots of Cork oak (Quercus Suber)

USGS Publications Warehouse

Ubeda, X.; Pereira, P.; Outeiro, L.; Martin, D.A.

2009-01-01

Cork oak, (Quercus suber) is widely distributed in the Mediterranean region, an area subject to frequent fires. The ash produced by burning can have impacts on the soil status and water resources that can differ according to the temperature reached during fire and the characteristics of the litter, defined as the dead organic matter accumulated on the soil surface prior to the fire. The aim of this work is to determine the physical and chemical characteristics of ash produced in laboratory experiments to approximate conditions typical of fires in this region. The litter of Quercus suber collected from two different plots on the Iberian Peninsula, Mas Bassets (Catalonia) and Albufeira (Portugal), was combusted at different temperatures for 2h. We measured Mass Loss (ML per cent), ash colour and CaCO3 content, pH, Electrical Conductivity (EC) and the major cations (Ca2+, Mg2+, K+ and Na+) released from ash slurries created by mixing ash with deionized water. The results showed that ML per cent is higher at all temperatures in Albufeira samples compared to Mas Bassets samples, except at 550??C, and the rate of loss increases faster with temperature than the Mas Bassets samples. At 150??C the ash colour is yellowish, becoming reddish at 200- 250??C and black at 300??C. Above 400??C the ash is grey/white. This thermal degradation is mostly observed in Albufeira litter. The formation of CaCO3 was identified at a lower temperature in Albufeira litter. At temperatures <300??C, pH and EC values are lower, rising at higher temperatures, especially in Albufeira slurries. The concentration of cations at lower temperatures does not differ substantially from the unburned sample except for Mg2+. The cation concentration increases at medium temperatures and decrease at higher temperatures, especially the concentration of divalent cations. The monovalent cations showed a larger concentration at moderate temperatures, mainly in Albufeira ash slurries. The analysis of the Ca:Mg ratio also showed that for the same temperature, a higher severity results for Albufeira litter. Potential negative effects on soil properties are observed at medium and higher temperatures. These negative effects include a higher percentage of mass loss, meaning more soil may be exposed to erosion, higher pH values and greater cation release from ash, especially monovalalent cations (K+,Na+) in higher proportions than the divalent ions (Ca2+, Mg2+), that can lead to impacts on soil physical properties like aggregate stability. Furthermore, the ions in ash may alter soil chemistry which may be detrimental to some plants thus altering the recovery of these ecosystems after fire. Low intensity prescribed fire can be a useful tool to land management in these sites, due to the reduced effects of fire temperatures on the physical and chemical properties of surface litter, and can reduce the risk of high temperature wildland fires by reducing fuel loadings. From the perspective of water resources, lower fire temperatures produce fewer impacts on the chemistry of overland flow and there is less probability that the soil surface will be eroded. Copyright ?? 2009 John Wiley & Sons, Ltd.

Regional assessment of emerald ash borer, Agrilus planipennis, impacts in forests of the Eastern United States

Treesearch

Randall S. Morin; Andrew M. Liebhold; Scott A. Pugh; Susan J. Crocker

2017-01-01

Native to Asia, the emerald ash borer (Agrilus planipennis Fairmaire) has caused extensive mortality of ash tree species (Fraxinus spp.) in the eastern United States. As of 2013, the pest was documented in 18 % of counties within the natural range of ash in the eastern United States. Regional forest inventory data from the U.S...

Post-fire recovery of soil organic matter in a Cambisol from typical Mediterranean forest in Southwestern Spain.

PubMed

Jiménez-González, Marco A; De la Rosa, José María; Jiménez-Morillo, Nicasio T; Almendros, Gonzalo; González-Pérez, José Antonio; Knicker, Heike

2016-12-01

Wildfire is a recurrent phenomenon in Mediterranean ecosystems and contributes to soil degradation and desertification, which are partially caused by alterations to soil organic matter (SOM). The SOM composition from a Cambisol under a Mediterranean forest affected by a wildfire is studied in detail in order to assess soil health status and better understand of soil recovery after the fire event. The soil was sampled one month and twenty-five months after the wildfire. A nearby unburnt site was taken as control soil. Soil rehabilitation actions involving heavy machinery to remove burnt vegetation were conducted sixteen months after the wildfire. Immediately after fire the SOM increased in topsoil due to inputs from charred vegetation, whereas a decrease was observed in the underlying soil layer. Twenty-five months after fire soil-pH increased in fire-affected topsoil due to the presence of ashes, a decrease in SOM content was recorded for the burnt topsoil and similar trend was observed for the water holding capacity. The pyro-chromatograms of burned soils revealed the formation of additional aromatic compounds. The thermal cracking of long-chain n-alkanes was also detected. Solid-state 13 C NMR spectroscopy supported the increase of aromatic compounds in the fire-affected topsoil due to the accumulation of charcoal, whereas the deeper soil sections were not affected by the fire. Two years later, soil parameters for the unburnt and burnt sites showed comparable values. The reduction of the relative intensity in the aromatic C region of the NMR spectra indicated a decrease in the charcoal content of the topsoil. Due to the negligible slope in the sampling site, the loss of charcoal was explained by the post-fire restoration activity, degradation, leaching of pyrogenic SOM into deeper soil horizons or wind erosion. Our results support that in the Mediterranean region, fire-induced alteration of the SOM is not lasting in the long-term. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterizations of Deposited Ash During Co-Firing of White Pine and Lignite in Fluidized Bed Combustor

NASA Astrophysics Data System (ADS)

Shao, Yuanyuan; Zhu, Jesse; Preto, Fernando; Tourigny, Guy; Wang, Jinsheng; Badour, Chadi; Li, Hanning; Xu, Chunbao Charles

Characterizations of ash deposits from co-firing/co-combusting of a woody biomass (i.e., white pine) and lignite coal were investigated in a fluidized-bed combustor using a custom designed air-cooled probe installed in the freeboard region of the reactor. Ash deposition behaviors on a heat transfer surface were comprehensively investigated and discussed under different conditions including fuel type, fuel blending ratios (20-80% biomass on a thermal basis), and moisture contents. For the combustion of 100% lignite, the compositions of the deposited ash were very similar to those of the fuel ash, while in the combustion of 100% white pine pellets or sawdust the deposited ash contained a much lower contents of CaO, SO3, K2O and P2O5 compared with the fuel ash, but the deposited ash was enriched with SiO2, Al2O3 and MgO. A small addition of white pine (20% on a heat input basis) to the coal led to the highest ash deposition rates likely due to the strong interaction of the CaO and MgO (from the biomass ash) with the alumina and silica (from the lignite ash) during the co-combustion process, evidenced by the detection of high concentrations of calcium/magnesium sulfates, aluminates and silicates in the ash deposits. Interestingly, co-firing of white pine pellets and lignite at a 50% blending ratio led to the lowest ash deposition rates. Ash deposition rates in combustion of fuels as received with a higher moisture content was found to be much lower than those of oven-dried fuels.

Climate change reverses the competitive balance of ash and beech seedlings under simulated forest conditions.

PubMed

Saxe, H; Kerstiens, G

2005-07-01

This study identifies the important role of climate change and photosynthetic photon flux density (PPFD) in the regenerative competence of ash and beech seedlings in 12 inter- and intra-specific competition designs in simulated mixed ash-beech forest gaps under conditions of non-limiting soil volume, water and nutrient supply. The growth conditions simulated natural forest conditions as closely as possible. Simulations were performed by growing interacting seedling canopies for one season in temperature-regulated closed-top chambers (CTCs). Eight CTCs were used in a factorial design with replicate treatments of [CO2] x temperature x PPFD x competition design. [CO2] tracked ambient levels or was 360 micromol mol-1 higher. Temperature tracked ambient levels or was 2.8 degrees C higher. PPFD on two plant tables inside each CTC was 16% and 5% of open-field levels, respectively, representative of typical light flux levels in a natural forest gap. In several of the competition designs, climate change made the ash seedlings grow taller than the beech seedlings and, at the same time, attain a larger leaf area and a larger total biomass. Advantages of this type for ash were found particularly at lower PPFD. There was a positive synergistic interaction of elevated temperature x [CO2] for both species, but more so for ash. There are many uncertainties when a study of chambered seedlings is to be projected to real changes in natural forests. Nevertheless, this study supports a possible future shift towards ash in north European, unmanaged, mixed ash-beech forests in response to the predicted climate change.

Volcanic-ash-derived forest soils of the inland Northwest: Properties and implications for management and restoration

Treesearch

Deborah Page-Dumroese; Richard Miller; Jim Mital; Paul McDaniel; Dan Miller

2007-01-01

Volcanic ash from the eruption of Mt. Mazama ~7,700 years ago has a strong influence on many forested landscapes of the Pacific Northwest and Intermountain regions of the USA and Canada. Because of the unique biological, physical and chemical properties of the ash, it is closely tied to plant communities and forest productivity, and should therefore be considered as a...

The U.S. Forest Service National Seed Laboratory and Fraxinus ex situ genetic conservation

Treesearch

Robert P. Karrfalt

2010-01-01

The U.S. Forest Service's National Seed Laboratory (NSL) has as part of its mission the conservation of genetic resources for the Forest Service and Forest Service cooperators through long-term seed storage. The Forest Service recognizes ash as one of four priority species for genetic conservation. The NSL is in charge of the Forest Service ash preservation plan...

Can ash clog soil pores?

NASA Astrophysics Data System (ADS)

Stoof, Cathelijne; Stoof, Cathelijne; Gevaert, Anouk; Gevaert, Anouk; Baver, Christine; Baver, Christine; Hassanpour, Bahareh; Hassanpour, Bahareh; Morales, Veronica; Morales, Veronica; Zhang, Wei; Zhang, Wei; Martin, Deborah; Martin, Deborah; Steenhuis, Tammo; Steenhuis, Tammo

2015-04-01

Wildfire can greatly increase a landscape's vulnerability to flooding and erosion events, and ash is thought to play a large role in controlling runoff and erosion processes after wildfire. Although ash can store rainfall and thereby reduce runoff and erosion for a limited period after wildfires, it has also been hypothesized to clog soil pores and reduce infiltration. Several researchers have attributed the commonly observed increase in runoff and erosion after fire to the potential pore-clogging effect of ash. Evidence is however incomplete, as to date, research has solely focused on identifying the presence of ash in the soil, with the actual flow processes associated with the infiltration and pore-clogging of ash remaining a major unknown. In several laboratory experiments, we tested the hypothesis that ash causes pore clogging to the point that infiltration is hampered and ponding occurs. We first visualized and quantified pore-scale infiltration of water and ash in sand of a range of textures and at various infiltration rates, using a digital bright field microscope capturing both photo and video. While these visualization experiments confirm field and lab observation of ash washing into soil pores, we did not observe any clogging of pores, and have not been able to create conditions for which this does occur. Additional electrochemical analysis and measurement of saturated hydraulic conductivity indicate that pore clogging by ash is not plausible. Electrochemical analysis showed that ash and sand are both negatively charged, showing that attachment of ash to sand and any resulting clogging is unlikely. Ash also had quite high saturated conductivity, and systems where ash was mixed in or lying on top of sand had similarly high hydraulic conductivity. Based on these various experiments, we cannot confirm the hypothesis that pore clogging by ash contributes to the frequently observed increase in post-fire runoff, at least for the medium to coarse sands evaluated here. Infiltration reductions and increases in runoff in these systems are more likely caused by the hydrologic effects of the textural interface between ash and soil, or by other fire-induced changes such as vegetation removal, decrease in roughness, and changes in soil water repellency. This is important information for determining the desired focus of post-fire management activities.

[Relationships of forest fire with lightning in Daxing' anling Mountains, Northeast China].

PubMed

Lei, Xiao-Li; Zhou, Guang-Sheng; Jia, Bing-Rui; Li, Shuai

2012-07-01

Forest fire is an important factor affecting forest ecosystem succession. Recently, forest fire, especially forest lightning fire, shows an increasing trend under global warming. To study the relationships of forest fire with lightning is essential to accurately predict the forest fire in time. Daxing' anling Mountains is a region with high frequency of forest lightning fire in China, and an important experiment site to study the relationships of forest fire with lightning. Based on the forest fire records and the corresponding lightning and meteorological observation data in the Mountains from 1966 to 2007, this paper analyzed the relationships of forest fire with lightning in this region. In the period of 1966-2007, both the lightning fire number and the fired forest area in this region increased significantly. The meteorological factors affecting the forest lighting fire were related to temporal scales. At yearly scale, the forest lightning fire was significantly correlated with precipitation, with a correlation coefficient of -0.489; at monthly scale, it had a significant correlation with air temperature, the correlation coefficient being 0.18. The relationship of the forest lightning fire with lightning was also related to temporal scales. At yearly scale, there was no significant correlation between them; at monthly scale, the forest lightning fire was strongly correlated with lightning and affected by precipitation; at daily scale, a positive correlation was observed between forest lightning fire and lightning when the precipitation was less than 5 mm. According to these findings, a fire danger index based on ADTD lightning detection data was established, and a forest lightning fire forecast model was developed. The prediction accuracy of this model for the forest lightning fire in Daxing' anling Mountains in 2005-2007 was > 80%.

Increased PCDD/F formation in the bottom ash from fires of CCA-treated wood.

PubMed

Tame, N W; Dlugogorski, B Z; Kennedy, E M

2003-03-01

Bottom ash that was the result of the combustion of chromated copper arsenate (CCA) treated wood under controlled fire conditions showed an increase of several orders of magnitude in the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), compared to that of untreated timber. Wood that has been pressure treated with CCA contains copper (II), which is known to catalyse the so-called de novo formation of PCDD/Fs. Comparable levels of PCDD/Fs would be expected in residual ash from burning CCA-treated wood in backyard fires, stoves and wood heaters, as a consequence of similar combustion conditions.

Fire in the Brazilian Amazon : 3. Dynamics of biomass, C, and nutrient pools in regenerating forests.

PubMed

Hughes, R F; Kauffman, J B; Cummings, D L

2000-09-01

Regenerating forests have become a common land-cover type throughout the Brazilian Amazon. However, the potential for these systems to accumulate and store C and nutrients, and the fluxes resulting from them when they are cut, burned, and converted back to croplands and pastures have not been well quantified. In this study, we quantified pre- and post-fire pools of biomass, C, and nutrients, as well as the emissions of those elements, at a series of second- and third-growth forests located in the states of Pará and Rondônia, Brazil. Total aboveground biomass (TAGB) of second- and third-growth forests averaged 134 and 91 Mg ha -1 , respectively. Rates of aboveground biomass accumulation were rapid in these systems, but were not significantly different between second- and third-growth forests, ranging from 9 to 16 Mg ha -1 year -1 . Residual pools of biomass originating from primary forest vegetation accounted for large portions of TAGB in both forest types and were primarily responsible for TAGB differences between the two forest types. In second-growth forests this pool (82 Mg ha -1 ) represented 58% of TAGB, and in third-growth forests (40 Mg ha -1 ) it represented 40% of TAGB. Amounts of TAGB consumed by burning of second- and third-growth forests averaged 70 and 53 Mg ha -1 , respectively. Aboveground pre-fire pools in second- and third-growth forests averaged 67 and 45 Mg C ha -1 , 821 and 707 kg N ha -1 , 441 and 341 kg P ha -1 , and 46 and 27 kg Ca ha -1 , respectively. While pre-fire pools of C, N, S and K were not significantly different between second- and third-growth forests, pools of both P and Ca were significantly higher in second-growth forests. This suggests that increasing land use has a negative impact on these elemental pools. Site losses of elements resulting from slashing and burning these sites were highly variable: losses of C ranged from 20 to 47 Mg ha -1 ; N losses ranged from 306 to 709 kg ha -1 ; Ca losses ranged from 10 to 145 kg ha -1 ; and P losses ranged from 2 to 20 kg ha -1 . Elemental losses were controlled to a large extent by the relative distribution of elemental mass within biomass components of varying susceptibilities to combustion and the temperatures of volatilization of each element. Due to a relatively low temperature of volatilization and its concentration in highly combustible biomass pools, site losses of N averaged 70% of total pre-fire pools. In contrast, site losses of P and Ca resulting from burning were 33 and 20% of total pre-fire pools, respectively, as much of the mass of those elements was deposited on site as ash. Pre- and post-fire biomass and elemental pools of second- and third-growth forests, as well as the emissions from those systems, were intermediate between those of primary forests and pastures in the Brazilian Amazon. Overall, regenerating forests have the capacity to act as either large terrestrial sinks or sources of C and nutrients, depending on the course of land-use patterns within the Brazilian Amazon. Combining remote sensing techniques with field measures of aboveground C accumulation in regenerating forests and C fluxes from those forests when they are cut and burned, we estimate that during 1990-1991 roughly 104 Tg of C was accumulated by regenerating forests across the Brazilian Amazon. Further, we estimate that approximately 103 Tg of C was lost via the cutting and burning of regenerating forests across the Brazilian Amazon during this same period. Since average C accumulations (5.5 Mg ha -1 year -1 ) in regenerating forests were 19% of the C lost when such forests are cut and burned (29.3 Mg ha -1 ), our results suggest that when less than 19% of the total area accounted for by secondary forests is cut and burned in a given year, those forests will be net accumulators of C during that year. Conversely, when more than 19% of regenerating forests are burned, those forests will be a net source of C to the atmosphere.

Magnetic mapping of distribution of wood ash used for fertilization of forest soil.

PubMed

Petrovský, Eduard; Remeš, Jiří; Kapička, Aleš; Podrázský, Vilém; Grison, Hana; Borůvka, Luboš

2018-06-01

The effect of wood-ash fertilization on forest soils has been assessed mainly through geochemical methods (e.g., content of soil organic matter or nutrients). However, a simple and fast method of determining the distribution of the ash and the extent of affected soil is missing. In this study we present the use of magnetic susceptibility, which is controlled by Fe-oxides, in comparing the fertilized soil in the forest plantation of pine and oak with intact forest soil. Spatial and vertical distribution of magnetic susceptibility was measured in an oak and pine plantation next to stems of young plants, where wood ash was applied as fertilizer. Pattern of the susceptibility distribution was compared with that in non-fertilized part of the plantation as well as with a spot of intact natural forest soil nearby. Our results show that the wood-ash samples contain significant amount of ferrimagnetic magnetite with susceptibility higher than that of typical forest soil. Clear differences were observed between magnetic susceptibility of furrows and ridges. Moreover, the dispersed ash remains practically on the surface, does not penetrate to deeper layers. Finally, our data suggest significant differences in surface values between the pine and oak plants. Based on this study we may conclude that magnetic susceptibility may represent a simple and approximate method of assessing the extent of soil affected by wood-ash. Copyright © 2018 Elsevier B.V. All rights reserved.

COAL-FIRED POWER PLANT ASH UTILIZATION IN THE TVA REGION

EPA Science Inventory

The report gives results of a study: (1) to summarize (a) production of coal ash nationally and by TVA's 12 major ash-producing steam/electric power plants, and (b) the physical/chemical characteristics of coal ash that affect ash disposal and/or use; (2) to review reported metho...

Physical and biological studies of coal and oil fly ash.

PubMed Central

Fisher, G L; McNeill, K L; Prentice, B A; McFarland, A R

1983-01-01

Studies were performed to compare the physical and chemical characteristics and the in vitro macrophage cytotoxicity of oil and coal fly ash. Sampling methodology was developed to collect size-fractionated particulate matter from the smokestack of either a coal-fired or an oil-fired power plant. Morphological studies demonstrated particle heterogeneity, although most coal fly ash particles appeared to be spherical. Oil fly ash contained two major morphologies; nonopaque amorphous particles and opaque amorphous particles. Elemental analysis indicates that the coal ash is predominantly composed of aluminosilicate particles, while the oil ash is predominantly inorganic sulfates and carbonaceous particles. In vitro macrophage assays demonstrate that the finest coal fly ash particles are the most cytotoxic; the cytotoxicity is significantly less than that of alpha-quartz, the positive control particle. In contrast, the oil fly ash particles are more cytotoxic than quartz. The cytotoxicity of oil fly ash is due to soluble components, possibly vanadium salts. Images FIGURE 2. A FIGURE 2. B FIGURE 2. C FIGURE 2. D PMID:6641653

Effects of Late Stages of Emerald Ash Borer (Coleoptera: Buprestidae)-Induced Ash Mortality on Forest Floor Invertebrate Communities

PubMed Central

Herms, Daniel A

2017-01-01

Abstract Emerald ash borer (EAB; Agrilus planipennis Fairmaire) is an invasive wood-borer causing rapid, widespread ash tree mortality, formation of canopy gaps, and accumulation of coarse woody debris (CWD) in forest ecosystems. The objective of this study was to quantify the effects of canopy gaps and ash CWD on forest floor invertebrate communities during late stages of EAB-induced ash mortality, when the effects of gaps are predicted to be smallest and effects of CWD are predicted to be greatest, according to the model proposed by Perry and Herms 2016a. A 2-year study was conducted in forest stands that had experienced nearly 100% ash mortality in southeastern Michigan, USA, near where EAB first established in North America. In contrast to patterns documented during early stages of the EAB invasion, effects of gaps were minimal during late stages of ash mortality, but invertebrate communities were affected by accumulation and decomposition of CWD. Invertebrate activity-abundance, evenness, and diversity were highest near minimally decayed logs (decay class 1), but diverse taxon-specific responses to CWD affected community composition. Soil moisture class emerged as an important factor structuring invertebrate communities, often mediating the strength and direction of their responses to CWD and stages of decomposition. The results of this study were consistent with the predictions that the effects of CWD on invertebrate communities would be greater than those of canopy gaps during late stages of EAB-induced ash mortality. This research contributes to understanding of the cascading and long-term ecological impacts of invasive species on native forest ecosystems.

Building double-decker traps for early detection of emerald ash borer

Treesearch

Deborah G. McCullough; Therese M. Poland

2017-01-01

Emerald ash borer (EAB) (Agrilus planipennis Fairmaire), the most destructive forest insect to have invaded North America, has killed hundreds of millions of forest and landscape ash (Fraxinus spp.) trees. Several artificial trap designs to attract and capture EAB beetles have been developed to detect, delineate, and monitor...

Development of a web-based tool for projecting costs of managing emerald ash borer in municipal forests

Treesearch

Clifford S. Sadof

2009-01-01

City managers faced with the invasion of emerald ash borer into their urban forests need to plan for the invasion in order to obtain the resources they need to protect the public from harm caused by dying ash trees. Currently, city...

Hazard Science in Support of Community Resiliency: The Response of the Multi Hazards Demonstration Project to the 2009 Station Fire in Los Angeles County

NASA Astrophysics Data System (ADS)

Jones, L. M.; Bawden, G. W.; Bowers, J.; Cannon, S.; Cox, D. A.; Fisher, R.; Keeley, J.; Perry, S. C.; Plumlee, G. S.; Wood, N. J.

2009-12-01

The “Station” fire, the largest fire in the history of Los Angeles County in southern California, began on August 26, 2009 and as of the abstract deadline had burned over 150,000 acres of the Angeles National Forest. This fire creates both a demand and an opportunity for hazards science to be used by the communities directly hit by the fire, as well as those downstream of possible postfire impacts. The Multi Hazards Demonstration Project of the USGS is deploying several types of scientific response, including 1) evaluation of potential debris-flow hazards and associated risk, 2) monitoring physical conditions in burned areas and the hydrologic response to rainstorms, 3) increased streamflow monitoring, 4) ash analysis and ground water contamination, 5) ecosystem response and endangered species rescue, 6) lidar data acquisition for evaluations of biomass loss, detailed mapping of the physical processes that lead to debris-flow generation, and other geologic investigations. The Multi Hazards Demonstration Project is working with the southern California community to use the resulting information to better manage the social consequences of the fire and its secondary hazards. In particular, we are working with Los Angeles County to determine what information they need to prioritize recovery efforts. For instance, maps of hazards specific to debris flow potential can help identify the highest priority areas for debris flow mitigation efforts. These same maps together with ecosystem studies will help land managers determine whether individuals from endangered species should be removed to zoos or other refuges during the rainy months. The ash analysis will help water managers prevent contamination to water supplies. Plans are just beginning for a public information campaign with Los Angeles County about the risk posed by potential debris flows that should be underway in December. Activities from the fire response will support the development of the Wildfire Scenario in 2011, which will examine implications of land-use decisions in the frequency of fires in southern California.

Trace element partitioning in ashes from boilers firing pure wood or mixtures of solid waste with respect to fuel composition, chlorine content and temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saqib, Naeem, E-mail: naeem.saqib@oru.se; Bäckström, Mattias, E-mail: mattias.backstrom@oru.se

Highlights: • Different solids waste incineration is discussed in grate fired and fluidized bed boilers. • We explained waste composition, temperature and chlorine effects on metal partitioning. • Excessive chlorine content can change oxide to chloride equilibrium partitioning the trace elements in fly ash. • Volatility increases with temperature due to increase in vapor pressure of metals and compounds. • In Fluidized bed boiler, most metals find themselves in fly ash, especially for wood incineration. - Abstract: Trace element partitioning in solid waste (household waste, industrial waste, waste wood chips and waste mixtures) incineration residues was investigated. Samples of flymore » ash and bottom ash were collected from six incineration facilities across Sweden including two grate fired and four fluidized bed incinerators, to have a variation in the input fuel composition (from pure biofuel to mixture of waste) and different temperature boiler conditions. As trace element concentrations in the input waste at the same facilities have already been analyzed, the present study focuses on the concentration of trace elements in the waste fuel, their distribution in the incineration residues with respect to chlorine content of waste and combustion temperature. Results indicate that Zn, Cu and Pb are dominating trace elements in the waste fuel. Highly volatile elements mercury and cadmium are mainly found in fly ash in all cases; 2/3 of lead also end up in fly ash while Zn, As and Sb show a large variation in distribution with most of them residing in the fly ash. Lithophilic elements such as copper and chromium are mainly found in bottom ash from grate fired facilities while partition mostly into fly ash from fluidized bed incinerators, especially for plants fuelled by waste wood or ordinary wood chips. There is no specific correlation between input concentration of an element in the waste fuel and fraction partitioned to fly ash. Temperature and chlorine content have significant effects on partitioning characteristics by increasing the formation and vaporization of highly volatile metal chlorides. Zinc and cadmium concentrations in fly ash increase with the incineration temperature.« less

Focused sunlight factor of forest fire danger assessment using Web-GIS and RS technologies

NASA Astrophysics Data System (ADS)

Baranovskiy, Nikolay V.; Sherstnyov, Vladislav S.; Yankovich, Elena P.; Engel, Marina V.; Belov, Vladimir V.

2016-08-01

Timiryazevskiy forestry of Tomsk region (Siberia, Russia) is a study area elaborated in current research. Forest fire danger assessment is based on unique technology using probabilistic criterion, statistical data on forest fires, meteorological conditions, forest sites classification and remote sensing data. MODIS products are used for estimating some meteorological conditions and current forest fire situation. Geonformation technologies are used for geospatial analysis of forest fire danger situation on controlled forested territories. GIS-engine provides opportunities to construct electronic maps with different levels of forest fire probability and support raster layer for satellite remote sensing data on current forest fires. Web-interface is used for data loading on specific web-site and for forest fire danger data representation via World Wide Web. Special web-forms provide interface for choosing of relevant input data in order to process the forest fire danger data and assess the forest fire probability.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The seven presentations (in pdf format) on the CD-ROM are: Amended Silicates{trademark}: mercury control without harming fly ash (J. Butz and others); benefits of gypsum in agriculture (L.D. Norton); co-firing biomass in pc fired units (C. Meijer and others); minimizing the impact of air pollution control equipment retrofits on saleability of fly ash (C.Weilert); new power plant construction - CCP readiness (T. Jansen); recent utilization of fly ash in coal plant construction (J. Liljegren and T. Hart); and resource conservation challenge (C. McLaughlin).

Rare earth minerals in a “no tonstein” section of the Dean (Fire Clay) coal, Knox County, Kentucky

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hower, James C.; Berti, Debora; Hochella, Michael F.

The Dean (Fire Clay) coal in Knox County, Kentucky, does not contain the megascopically-visible ash-fall tonstein present in most other sections of the coal bed. Like the Fire Clay tonstein, a low-ash portion of the coal is enriched in rare earth elements (>2400 ppm, on ash basis). In addition to kaolinite produced in the diagenesis of volcanic glass, transmission electron microscopy studies indicate the coal contains primary kaolinite, LaCeNdTh monazite, barium niobate, native gold, and FeNiCr spinels. The mineral assemblages, particularly the kaolinite-monazite association and its similarity to the tonsteins in coal to the east, demonstrate the coal was subjectmore » to the REE-enriched volcanic ash fall, apparently just at a more dilute level than at locations where the tonstein is present.« less

Rare earth minerals in a “no tonstein” section of the Dean (Fire Clay) coal, Knox County, Kentucky

DOE PAGES

Hower, James C.; Berti, Debora; Hochella, Michael F.; ...

2018-05-03

The Dean (Fire Clay) coal in Knox County, Kentucky, does not contain the megascopically-visible ash-fall tonstein present in most other sections of the coal bed. Like the Fire Clay tonstein, a low-ash portion of the coal is enriched in rare earth elements (>2400 ppm, on ash basis). In addition to kaolinite produced in the diagenesis of volcanic glass, transmission electron microscopy studies indicate the coal contains primary kaolinite, LaCeNdTh monazite, barium niobate, native gold, and FeNiCr spinels. The mineral assemblages, particularly the kaolinite-monazite association and its similarity to the tonsteins in coal to the east, demonstrate the coal was subjectmore » to the REE-enriched volcanic ash fall, apparently just at a more dilute level than at locations where the tonstein is present.« less

EFFECT OF CONVENTIONAL AND ADVANCED COAL CONVERSION BY-PRODUCTS ON THE PULMONARY SYSTEM

EPA Science Inventory

To evaluate the environmental impact of different energy technologies, fly ash samples collected from a coal-fired and from an oil-fired electric power plant were used in aerosol inhalation exposures of mice. The effects of multiple 3-h exposures to the fly ash particles at 2 and...

Multi-temporal analysis of forest fire risk driven by environmental and socio-economic change in the Republic of Korea

NASA Astrophysics Data System (ADS)

Kim, S. J.; Lim, C. H.; Kim, G. S.; Lee, W. K.

2017-12-01

Analysis of forest fire risk is important in disaster risk reduction (DRR) since it provides a way to manage forest fires. Climate and socio-economic factors are important in the cause of forest fires, and the role of the socio-economic factors in prevention and preparedness of forest fires is increasing. As most of the forest fires in the Republic of Korea are highly related to human activities, both environmental factors and socio-economic factors were considered into the analysis of forest fire risk. In this study, the Maximum Entropy (MaxEnt) model was used to predict the potential geographical distribution and probability of forest fire occurrence spatially and temporally from 1980s to the 2010s in the Republic of Korea by multi-temporal analysis and analyze the relationship between forest fires and the factors. As a result of the risk analysis, there was an overall increasing trend in forest fire risk from the 1980s to the 2000s, and socio-economic factors were highly correlated with the occurrence of forest fires. The study demonstrates that the socio-economic factors considered as human activities can increase the occurrence of forest fires. The result implies that managing human activities are significant to prevent forest fire occurrence. In addition, timely forest fire prevention and control is necessary as drought index such as Standardized Precipitation Index (SPI) also affected forest fires.

Can pore-clogging by ash explain post-fire runoff?

USGS Publications Warehouse

Stoof, Cathelijne R.; Gevaert, Anouk I.; Baver, Christine; Hassanpour, Bahareh; Morales, Veronica L.; Zhang, Wei; Martin, Deborah; Giri, Shree K.; Steenhuis, Tammo S.

2016-01-01

Ash plays an important role in controlling runoff and erosion processes after wildfire and has frequently been hypothesised to clog soil pores and reduce infiltration. Yet evidence for clogging is incomplete, as research has focussed on identifying the presence of ash in soil; the actual flow processes remain unknown. We conducted laboratory infiltration experiments coupled with microscope observations in pure sands, saturated hydraulic conductivity analysis, and interaction energy calculations, to test whether ash can clog pores (i.e. block pores such that infiltration is hampered and ponding occurs). Although results confirmed previous observations of ash washing into pores, clogging was not observed in the pure sands tested, nor were conditions found for which this does occur. Clogging by means of strong attachment of ash to sand was deemed unlikely given the negative surface charge of the two materials. Ponding due to washing in of ash was also considered improbable given the high saturated conductivity of pure ash and ash–sand mixtures. This first mechanistic step towards analysing ash transport and attachment processes in field soils therefore suggests that pore clogging by ash is unlikely to occur in sands. Discussion is provided on other mechanisms by which ash can affect post-fire hydrology.

Quantifying foliar responses of white ash to ozone and simulated acid precipitation: an assessment proposal for forest exposure studies

Treesearch

Leon S. Dochinger; Keith F. Jensen; Keith F. Jensen

1990-01-01

Seedlings represent an important linkage for assessing the effect of air pollution on forests. This study examines the foliar responses of white ash seedlings to ozone and acid precipitation as a means of identifying atmospheric deposition effects on forests.

In-situ genetic conservation of white ash (Fraxinus americana) at the Allegheny national forest

Treesearch

Charles E. Flower; Elijah Aubihl; Jeremie Fant; Stephen Forry; Andrea Hille; Kathleen S. Knight; William K. Oldland; Alejandro A. Royo; Richard M. Turcotte

2017-01-01

The emerald ash borer (EAB, Agrilus planipennis) is a non-native forest pest that has been sweeping across North America causing widespread mortality of trees in the genus Fraxinus, which includes the economically valuable white ash (F. americana). The rapid spread and lethality of EAB, paired with low levels of natural...

Ash dieback in the Northeast

Treesearch

Robert W. Brandt

1961-01-01

A dieback condition among our ash trees is causing great concern among foresters and forest industries in the northeastern United States. There is good cause for concern. For example, a recent survey made by the New York Conservation Department in 18 eastern counties of the State revealed that about 70 percent of the woodland ash trees are dead or dying.

Community composition and structure had no effect on forest susceptibility to invasion by the emerald ash borer (Coleoptera: Buprestidae)

Treesearch

Annemarie Smith; Daniel A. Herms; Robert P. Long; Kamal J.K. Gandhi

2015-01-01

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a non-native, wood-boring beetle that has caused widespread mortality of ash (Fraxinus Linnaeus (Oleaceae)) in eastern North America. During 2004-2007, we determined whether forest community composition and structure of black (F. nigra...

Patterns among the ashes: Exploring the relationship between landscape pattern and the emerald ash borer

Treesearch

Susan J. Crocker; Dacia M. Meneguzzo; Greg C. Liknes

2010-01-01

Landscape metrics, including host abundance and population density, were calculated using forest inventory and land cover data to assess the relationship between landscape pattern and the presence or absence of the emerald ash borer (EAB) (Agrilus planipennis Fairmaire). The Random Forests classification algorithm in the R statistical environment was...

Effects of ashes from a Brazilian savanna wildfire on water, soil and biota: An ecotoxicological approach.

PubMed

Oliveira-Filho, Eduardo C; Brito, Darlan Q; Dias, Zelia M B; Guarieiro, Mayara S; Carvalho, Esther L; Fascineli, Maria L; Niva, Cintia C; Grisolia, Cesar K

2018-03-15

Wildfire is very common in Brazilian savannas, and its effects on water, soil and aquatic/soil organisms are poorly understood. In this study, we observed the effects of fire, especially of ashes, on surface soil and subsurface water in a typical Brazilian savanna (Cerrado sensu strictu) for one year. Soil analyses (pH, organic matter content, potential acidity, K, Ca, Mg and P) and subsurface water analyses (NO 3- , PO 4 3- Mg 2+ , Ca 2+ and K + ) were assessed. We evaluated the ecotoxicological effects of ashes on three different endpoints and species, in fish Danio rerio (embryonic development), aquatic snail Biomphalaria glabrata (reproduction) and a soil species Enchytraeus sp. (reproduction). We found a higher amount of exchangeable cations and organic matter content in short-term fire effects on soil, but the higher availability of nutrients did not affect the soil pH in field plots. The effects of ashes on soil and subsurface water did not persist for one-year post-fire, except for organic matter content in burned areas. No toxic effects were observed on hatching success and incidences of developmental abnormalities in D. rerio embryos. However, ash input had adverse effects on reproduction in snails and enchytraeids. We reported a statistically significant decrease in snail eggs exposed to the 50g.L -1 and 100g.L -1 of ashes after four weeks (p<0.05, Dunnett's test and Tukey test). Enchytraeus sp. reproduction was negatively influenced by the natural soil, which presents high acidity, and also when exposed directly to the ashes from burned area, suggesting that pH and other ash compounds may limit the growth of enchytraeids. More studies in burned areas are strongly encouraged, addressing the potential important routes of exposure to ashes in order to understand the impact of intense fires on soil and aquatic biota in tropical savannas. Copyright © 2017 Elsevier B.V. All rights reserved.

Estimation of postfire nutrient loss in the Florida everglades.

PubMed

Qian, Y; Miao, S L; Gu, B; Li, Y C

2009-01-01

Postfire nutrient release into ecosystem via plant ash is critical to the understanding of fire impacts on the environment. Factors determining a postfire nutrient budget are prefire nutrient content in the combustible biomass, burn temperature, and the amount of combustible biomass. Our objective was to quantitatively describe the relationships between nutrient losses (or concentrations in ash) and burning temperature in laboratory controlled combustion and to further predict nutrient losses in field fire by applying predictive models established based on laboratory data. The percentage losses of total nitrogen (TN), total carbon (TC), and material mass showed a significant linear correlation with a slope close to 1, indicating that TN or TC loss occurred predominantly through volatilization during combustion. Data obtained in laboratory experiments suggest that the losses of TN, TC, as well as the ratio of ash total phosphorus (TP) concentration to leaf TP concentration have strong relationships with burning temperature and these relationships can be quantitatively described by nonlinear equations. The potential use of these nonlinear models relating nutrient loss (or concentration) to temperature in predicting nutrient concentrations in field ash appear to be promising. During a prescribed fire in the northern Everglades, 73.1% of TP was estimated to be retained in ash while 26.9% was lost to the atmosphere, agreeing well with the distribution of TP during previously reported wild fires. The use of predictive models would greatly reduce the cost associated with measuring field ash nutrient concentrations.

Forest-fire models

Treesearch

Haiganoush Preisler; Alan Ager

2013-01-01

For applied mathematicians forest fire models refer mainly to a non-linear dynamic system often used to simulate spread of fire. For forest managers forest fire models may pertain to any of the three phases of fire management: prefire planning (fire risk models), fire suppression (fire behavior models), and postfire evaluation (fire effects and economic models). In...

Economic analysis of emerald ash borer (Coleoptera: Buprestidae) management options.

PubMed

Vannatta, A R; Hauer, R H; Schuettpelz, N M

2012-02-01

Emerald ash borer, Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae), plays a significant role in the health and extent of management of native North American ash species in urban forests. An economic analysis of management options was performed to aid decision makers in preparing for likely future infestations. Separate ash tree population valuations were derived from the i-Tree Streets program and the Council of Tree and Landscape Appraisers (CTLA) methodology. A relative economic analysis was used to compare a control option (do-nothing approach, only removing ash trees as they die) to three distinct management options: 1) preemptive removal of all ash trees over a 5 yr period, 2) preemptive removal of all ash trees and replacement with comparable nonash trees, or 3) treating the entire population of ash trees with insecticides to minimize mortality. For each valuation and management option, an annual analysis was performed for both the remaining ash tree population and those lost to emerald ash borer. Retention of ash trees using insecticide treatments typically retained greater urban forest value, followed by doing nothing (control), which was better than preemptive removal and replacement. Preemptive removal without tree replacement, which was the least expensive management option, also provided the lowest net urban forest value over the 20-yr simulation. A "no emerald ash borer" scenario was modeled to further serve as a benchmark for each management option and provide a level of economic justification for regulatory programs aimed at slowing the movement of emerald ash borer.

The effect of emerald ash borer-caused tree mortality on the invasive shrub Amur honeysuckle and their combined effects on tree and shrub seedlings

Treesearch

Brian M. Hoven; David L. Gorchov; Kathleen S. Knight; Valerie E. Peters

2017-01-01

Invasive insects and plants are major threats to the health and viability of North American forests. Emerald ash borer (Agrilus planipennis) (EAB) may cause extensive changes to forest composition due to rapid ash (Fraxinus spp.) mortality. Invasive shrubs like Amur honeysuckle (Lonicera maackii) may...

Evidence of Ash Tree (Fraxinus spp.) Specific Associations with Soil Bacterial Community Structure and Functional Capacity

Treesearch

Michael P. Ricketts; Charles E. Flower; Kathleen S. Knight; Miquel A. Gonzalez-Meler

2018-01-01

The spread of the invasive emerald ash borer (EAB) across North America has had enormous impacts on temperate forest ecosystems. The selective removal of ash trees (Fraxinus spp.) has resulted in abnormally large inputs of coarse woody debris and altered forest tree community composition, ultimately affecting a variety of ecosystem processes. The...

The response of Fraxinus nigra forest ground-layer vegetation to emulated emerald ash borer mortality and management strategies in northern Minnesota, USA

Treesearch

Christopher E. Looney; Anthony W. D' Amato; Brian J. Palik; Robert A. Slesak; Mitchell A. Slater

2017-01-01

When an invasive organism targets a dominant tree species, it can trigger unprecedented shifts in forest plant communities. Emerald ash borer (EAB; Agrilus planipennis Fairmaire), an invasive insect that kills by girdling trees, represents a significant threat to North American Fraxinus (ash) species. EAB has already decimated...

Overstory treatment and planting season affect survival of replacement tree species in emerald ash borer threatened Fraxinus nigra forests in Minnesota, USA

Treesearch

Christopher E. Looney; Anthony W. D' Amato; Brian J. Palik; Robert A. Slesak

2015-01-01

Fraxinus nigra Marsh. (black ash) wetland forests in northern Minnesota, USA, are threatened by the invasive insect, emerald ash borer (Agrilus planipennis Fairmaire (EAB)). A potential management option is promoting regeneration of tree species that are not EAB hosts to maintain ecosystem functions. Using an operational-scale...

European Ash (Fraxinus excelsior L.) dieback: Disintegrating forest in the mountain protected areas, Czech Republic

Treesearch

Stanislav Vacek; Zdenek Vacek; Daniel Bulusek; Tereza Putalova; Murat Sarginci; Otakar Schwarz; Petr Srutka; Vilem Podrazsky; W. Keith Moser

2015-01-01

European ash (Fraxinus excelsior) is an important tree species in most temperate forests in Europe. Its future is threatened however, especially by an invasive fungus, Hymenoscyphus fraxineus (Hymenoscyphus pseudoalbidus, Chalara fraxinea). The current study is focused on the health of ash in the Krkonoše Mountains National Park, Czech Republic. On permanent...

Assessing urban forest effects and values, Chicago's urban forest

Treesearch

David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Cherie Leblanc Fisher

2010-01-01

An analysis of trees in Chicago, IL, reveals that this city has about 3,585,000 trees with canopies that cover 17.2 percent of the area. The most common tree species are white ash, mulberry species, green ash, and tree-of-heaven. Chicago's urban forest currently stores about 716,000 tons of carbon...

Emerald ash borer impacts on visual preferences for urban forest recreation settings

Treesearch

Arne Arnberger; Ingrid E. Schneider; Martin Ebenberger; Renate Eder; Robert C. Venette; Stephanie A. Snyder; Paul H. Gobster; Ami Choi; Stuart Cottrell

2017-01-01

Extensive outbreaks of the emerald ash borer (Agrilus planipennis; EAB), an invasive forest insect, are having serious impacts on the cultural ecosystem services of urban forests in the United States and other countries. Limited experience with how such outbreaks might affect recreational opportunities prompted this investigation of visitors to a...

Forest fire risk zonation mapping using remote sensing technology

NASA Astrophysics Data System (ADS)

Chandra, Sunil; Arora, M. K.

2006-12-01

Forest fires cause major losses to forest cover and disturb the ecological balance in our region. Rise in temperature during summer season causing increased dryness, increased activity of human beings in the forest areas, and the type of forest cover in the Garhwal Himalayas are some of the reasons that lead to forest fires. Therefore, generation of forest fire risk maps becomes necessary so that preventive measures can be taken at appropriate time. These risk maps shall indicate the zonation of the areas which are in very high, high, medium and low risk zones with regard to forest fire in the region. In this paper, an attempt has been made to generate the forest fire risk maps based on remote sensing data and other geographical variables responsible for the occurrence of fire. These include altitude, temperature and soil variations. Key thematic data layers pertaining to these variables have been generated using various techniques. A rule-based approach has been used and implemented in GIS environment to estimate fuel load and fuel index leading to the derivation of fire risk zonation index and subsequently to fire risk zonation maps. The fire risk maps thus generated have been validated on the ground for forest types as well as for forest fire risk areas. These maps would help the state forest departments in prioritizing their strategy for combating forest fires particularly during the fire seasons.

Nano-silica as the go material on heat resistant tunnel lining

NASA Astrophysics Data System (ADS)

Omar, Faizah; Osman, S. A.; Mutalib, A.

2018-04-01

This paper is concerned with passive fire protection method of protective concrete mix that is made up of fly ash, polypropylene fibre, and nano-silica. Nano-silica is focused on as the innovative material to be used in the composition of the protective concrete mix. The previous experimental studies which analyse the performance of passive fire protection on tunnels are discussed. This paper also discusses passive fire protection. The fire protection materials and behaviour analyses of tunnel structure are also presented. At the end of the paper, the recommendation of the optimum composition concrete material with fly ash, polypropylene fibre and nano-silica as tunnel lining fire protective materials is proposed.

Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo.

PubMed

Hasani, F; Shala, F; Xhixha, G; Xhixha, M K; Hodolli, G; Kadiri, S; Bylyku, E; Cfarku, F

2014-12-01

The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of (40)K, (226)Ra and (232)Th in lignite are found to be 36 ± 8 Bq kg(-1), 9 ± 1 Bq kg(-1) and 9 ± 3 Bq kg(-1), respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry. Copyright © 2014 Elsevier Ltd. All rights reserved.

Trace element partitioning in ashes from boilers firing pure wood or mixtures of solid waste with respect to fuel composition, chlorine content and temperature.

PubMed

Saqib, Naeem; Bäckström, Mattias

2014-12-01

Trace element partitioning in solid waste (household waste, industrial waste, waste wood chips and waste mixtures) incineration residues was investigated. Samples of fly ash and bottom ash were collected from six incineration facilities across Sweden including two grate fired and four fluidized bed incinerators, to have a variation in the input fuel composition (from pure biofuel to mixture of waste) and different temperature boiler conditions. As trace element concentrations in the input waste at the same facilities have already been analyzed, the present study focuses on the concentration of trace elements in the waste fuel, their distribution in the incineration residues with respect to chlorine content of waste and combustion temperature. Results indicate that Zn, Cu and Pb are dominating trace elements in the waste fuel. Highly volatile elements mercury and cadmium are mainly found in fly ash in all cases; 2/3 of lead also end up in fly ash while Zn, As and Sb show a large variation in distribution with most of them residing in the fly ash. Lithophilic elements such as copper and chromium are mainly found in bottom ash from grate fired facilities while partition mostly into fly ash from fluidized bed incinerators, especially for plants fuelled by waste wood or ordinary wood chips. There is no specific correlation between input concentration of an element in the waste fuel and fraction partitioned to fly ash. Temperature and chlorine content have significant effects on partitioning characteristics by increasing the formation and vaporization of highly volatile metal chlorides. Zinc and cadmium concentrations in fly ash increase with the incineration temperature. Copyright © 2014 Elsevier Ltd. All rights reserved.

An approach to the real time risk evaluation system of boreal forest fire

NASA Astrophysics Data System (ADS)

Nakau, K.; Fukuda, M.; Kimura, K.; Hayasaka, H.; Tani, H.; Kushida, K.

2005-12-01

Huge boreal forest fire may cause massive impacts not only on global warming gas emission but also local communities. Thus, it is important to control forest fire. We collected data about boreal forest fire as satellite imagery and fire observation simultaneously in Alaska and east Siberia in summer fire seasons for these three years. Fire observation data was collected from aircraft flying between Japan and Europe. Fire detection results were compared with observed data to evaluate the accuracy and earliness of automatic detection. NOAA and MODIS satellite images covering Alaska and East Siberia are collected. We are also developing fire expansion simulation model to forecast the possible fire expansion area. On the basis of fire expansion forecast, risk analysis of possible fire expansion for decision aid of fire-fighting activities will be analyzed. To identify the risk of boreal forest fire and public concern about forest fire, we collected local news paper in Fairbanks, AK and discuss the statistics of articles related to forest fire on the newspaper.

Fire intensity impacts on post-fire temperate coniferous forest net primary productivity

NASA Astrophysics Data System (ADS)

Sparks, Aaron M.; Kolden, Crystal A.; Smith, Alistair M. S.; Boschetti, Luigi; Johnson, Daniel M.; Cochrane, Mark A.

2018-02-01

Fire is a dynamic ecological process in forests and impacts the carbon (C) cycle through direct combustion emissions, tree mortality, and by impairing the ability of surviving trees to sequester carbon. While studies on young trees have demonstrated that fire intensity is a determinant of post-fire net primary productivity, wildland fires on landscape to regional scales have largely been assumed to either cause tree mortality, or conversely, cause no physiological impact, ignoring the impacted but surviving trees. Our objective was to understand how fire intensity affects post-fire net primary productivity in conifer-dominated forested ecosystems on the spatial scale of large wildland fires. We examined the relationships between fire radiative power (FRP), its temporal integral (fire radiative energy - FRE), and net primary productivity (NPP) using 16 years of data from the MOderate Resolution Imaging Spectrometer (MODIS) for 15 large fires in western United States coniferous forests. The greatest NPP post-fire loss occurred 1 year post-fire and ranged from -67 to -312 g C m-2 yr-1 (-13 to -54 %) across all fires. Forests dominated by fire-resistant species (species that typically survive low-intensity fires) experienced the lowest relative NPP reductions compared to forests with less resistant species. Post-fire NPP in forests that were dominated by fire-susceptible species were not as sensitive to FRP or FRE, indicating that NPP in these forests may be reduced to similar levels regardless of fire intensity. Conversely, post-fire NPP in forests dominated by fire-resistant and mixed species decreased with increasing FRP or FRE. In some cases, this dose-response relationship persisted for more than a decade post-fire, highlighting a legacy effect of fire intensity on post-fire C dynamics in these forests.

Phosphorus release from ash and remaining tissues of two wetland species after a prescribed fire.

PubMed

Liu, G D; Gu, B; Miao, S L; Li, Y C; Migliaccio, K W; Qian, Y

2010-01-01

Dead plant tissues and ash from a prescribed fire play an important role in nutrient balance and cycling in the Florida Everglades ecosystem. The objective of this study was to assess the dynamic changes in total phosphorus release (TPr) from ash or tissues of either cattail (Typha domingensis Pers.) or sawgrass (Cladium jamaicense Crantz) to water. Natural-dead (senesced-dead) and burning-dead (standing-dead due to a prescribed fire) cattail and sawgrass were collected from highly (H) and moderately (M) impacted zones in the Florida Everglades. This experiment was conducted by incubation and water-extraction of the materials in plastic bottles for 65 d at room temperature (24 +/- 1 degrees C). Results showed that 63 to 88%, 17 to 48%, 9 to 20%, and 13 to 28% of total P (TPp) were released as TPr from cattail and sawgrass ash, cattail tissues from the H zone, cattail tissues, and sawgrass tissues from the M zone, respectively. TPp means total P of plant tissues, whereas TPr is total P release from the tissues or ash. Most of the TPr was released within 24 h after burning. The quick release of TPr observed in this experiment may help explain the P surge in the surface water immediately following a fire in the marsh. These findings suggest that prescribed burning accelerates P release from cattail and sawgrass. They also imply that it is very important to keep the water stagnant in the first 24 h to maximize the benefits of a prescribed fire in the Everglades.

Fire Patterns and Drivers of Fires in the West African Tropical Forest

NASA Astrophysics Data System (ADS)

Dwomoh, F. K.; Wimberly, M. C.

2015-12-01

The West African tropical forest (referred to as the Upper Guinean forest, UGF), is a global biodiversity hotspot providing vital ecosystem services for the region's socio-economic and environmental wellbeing. It is also one of the most fragmented and human-modified tropical forest ecosystems, with the only remaining large patches of original forests contained in protected areas. However, these remnant forests are susceptible to continued fire-mediated degradation and forest loss due to intense climatic, demographic and land use pressures. We analyzed human and climatic drivers of fire activity in the sub-region to better understand the spatial and temporal patterns of these risks. We utilized MODIS active fire and burned area products to identify fire activity within the sub-region. We measured climatic variability using TRMM rainfall data and derived indicators of human land use from a variety of geospatial datasets. We used a boosted regression trees model to determine the influences of predictor variables on fire activity. Our analyses indicated that the spatial and temporal variability of precipitation is a key driving factor of fire activity in the UGF. Anthropogenic effects on fire activity in the area were evident through the influences of agriculture and low-density populations. These human footprints in the landscape make forests more susceptible to fires through forest fragmentation, degradation, and fire spread from agricultural areas. Forested protected areas within the forest savanna mosaic experienced frequent fires, whereas the more humid forest areas located in the south and south-western portions of the study area had fewer fires as these rainforests tend to offer some buffering against fire encroachment. These results improve characterization of UGF fire regime and expand our understanding of the spatio-temporal dynamics of tropical forest fires in response to human and climatic pressures.

Modeling Forest Understory Fires in an Eastern Amazonian Landscape

NASA Technical Reports Server (NTRS)

Alencar, A. A. C.; Solorzano, L. A.; Nepstad, D. C.

2004-01-01

Forest understory fires are an increasingly important cause of forest impoverishment in Ammonia, but little is known of the landscape characteristics and climatic phenomena that determine their occurrence. We developed empirical functions relating the occurrence of understory fires to landscape features near Paragominas, a 35- yr-old ranching and logging center in eastern Ammonia. An historical sequence of maps of forest understory fire was created based on field interviews With local farmers and Landsat TM images. Several landscape features that might explain spatial variations in the occurrence of understory fires were also mapped and co-registered for each of the sample dates, including: forest fragment size and shape, forest impoverishment through logging and understory fires, source of ignition (settlements and charcoal pits), roads, forest edges, and others. The spatial relationship between forest understory fire and each landscape characteristic was tested by regression analyses. Fire probability models were then developed for various combinations of landscape characteristics. The analyses were conducted separately for years of the El Nino Southern Oscillation (ENSO), which are associated with severe drought in eastern Amazonia, and non-ENS0 years. Most (91 %) of the forest area that burned during the 10-yr sequence caught fire during ENSO years, when severe drought may have increased both forest flammability and the escape of agricultural management fires. Forest understory fires were associated with forest edges, as reported in previous studies from Ammonia. But the strongest predictor of forest fire was the percentage of the forest fragment that had been previously logged or burned. Forest fragment size, distance to charcoal pits, distance to agricultural settlement, proximity to forest edge, and distance to roads were also correlated with forest understory fire. Logistic regression models using information on fragment degradation and distance to ignition sources accurately predicted the location of lss than 80% of the forest fires observed during the ENSO event of 1997- 1998. In this Amazon landscape, forest understory fire is a complex function of several variables that influence both the flammability and ignition exposure of the forest.

Natural enemies implicated in the regulation of an invasive pest: a life table analysis of the population dynamics of the emerald ash borer

Treesearch

Jian J. Duan; Kristopher J. Abell; Leah S. Bauer; Juli Gould; Roy. Van Driesche

2014-01-01

The emerald ash borer Agrilus planipennis Fairmaire is a serious invasive forest pest of ash (Fraxinus) trees in North America. Life tables were constructed for both experimentally established cohorts and wild populations of A. planipennis on healthy host trees from 2008 to 2011 in six forests in central Michigan...

Physical and Chemical Characteristics of Ash-influenced Soils of Inland Northwest Forests

Treesearch

P. A. McDaniel; M. A. Wilson

2007-01-01

Holocene ash from the cataclysmic eruption of Mount Mazama (now Crater Lake) in southeastern Oregon is a major component of many forest soils that lie to the east of Cascade Mountains in the Pacific Northwest region. The relatively high productivity of the region’s ecosystems is closely linked to this volcanic ash component. This paper reports on the ecologically...

Gis-Based Multi-Criteria Decision Analysis for Forest Fire Risk Mapping

NASA Astrophysics Data System (ADS)

Akay, A. E.; Erdoğan, A.

2017-11-01

The forested areas along the coastal zone of the Mediterranean region in Turkey are classified as first-degree fire sensitive areas. Forest fires are major environmental disaster that affects the sustainability of forest ecosystems. Besides, forest fires result in important economic losses and even threaten human lives. Thus, it is critical to determine the forested areas with fire risks and thereby minimize the damages on forest resources by taking necessary precaution measures in these areas. The risk of forest fire can be assessed based on various factors such as forest vegetation structures (tree species, crown closure, tree stage), topographic features (slope and aspect), and climatic parameters (temperature, wind). In this study, GIS-based Multi-Criteria Decision Analysis (MCDA) method was used to generate forest fire risk map. The study was implemented in the forested areas within Yayla Forest Enterprise Chiefs at Dursunbey Forest Enterprise Directorate which is classified as first degree fire sensitive area. In the solution process, "extAhp 2.0" plug-in running Analytic Hierarchy Process (AHP) method in ArcGIS 10.4.1 was used to categorize study area under five fire risk classes: extreme risk, high risk, moderate risk, and low risk. The results indicated that 23.81 % of the area was of extreme risk, while 25.81 % was of high risk. The result indicated that the most effective criterion was tree species, followed by tree stages. The aspect had the least effective criterion on forest fire risk. It was revealed that GIS techniques integrated with MCDA methods are effective tools to quickly estimate forest fire risk at low cost. The integration of these factors into GIS can be very useful to determine forested areas with high fire risk and also to plan forestry management after fire.

[Change trends of summer fire danger in great Xing' an Mountains forest region of Heilongjiang Province, Northeast China under climate change].

PubMed

Yang, Guang; Shu, Li-Fu; Di, Xue-Ying

2012-11-01

By using Delta and WGEN downscaling methods and Canadian Forest Fire Weather Index, this paper analyzed the variation characteristics of summer fire in Great Xing' an Mountains forest region of Heilongjiang Province in 1966-2010, estimated the change trends of the summer fire danger in 2010-2099, compared the differences of the forest fire in summer, spring, and autumn, and proposed the prevention and control strategies of the summer fire based on the fire environment. Under the background of climate warming, the summer forest fire in the region in 2000-2010 showed a high incidence trend. In foreseeable future, the summer forest fire across the region in 2010-2099, as compared to that in the baseline period 1961-1990, would be increased by 34%, and the increment would be obviously greater than that of spring and autumn fire. Relative to that in 1961-1990, the summer fire in 2010-2099 under both SRES A2a and SRES B2a scenarios would have an increasing trend, and, with the lapse of time, the trend would be more evident, and the area with high summer fire would become wider and wider. Under the scenario of SRES A2a, the summer fire by the end of the 21st century would be doubled, as compared to that in 1961-1990, and the area with high summer fire would be across the region. In the characteristics of fire source, attributes of forest fuel, and fire weather conditions, the summer forest fire was different from the spring and autumn forest fire, and thus, the management of fire source and forest fuel load as well as the forest fire forecast (mid-long term forecast in particular) in the region should be strengthened to control the summer forest fire.

Neutron activation analysis of thermal power plant ash and surrounding area soils.

PubMed

Al-Masri, M S; Haddad, Kh; Alsomel, N; Sarhil, A

2015-08-01

Elemental concentrations of As, Cd, Co, Cr, Fe, Hg, Mo, Ni, Se, and Zn have been determined in fly and bottom ash collected from Syrian power plants fired by heavy oil and natural gas using instrumental neutron activation analysis. The results showed that all elements were more concentrated in fly ash than in the fly ash; there was a clear increasing trend of the elemental concentrations in the fly ash along the flue gas pathway. The annual emission of elements was estimated. Elemental concentrations were higher inside the campus area than in surrounding areas, and the lowest values were found in natural-gas-fired power plant. In addition, the levels have decreased as the distance from power plant campus increases. However, the levels in the surrounding villages were within the Syrian standard for agriculture soil.

Fire ecology of western Montana forest habitat types

Treesearch

William C. Fischer; Anne F. Bradley

1987-01-01

Provides information on fire as an ecological factor for forest habitat types in western Montana. Identifies Fire Groups of habitat types based on fire's role in forest succession. Describes forest fuels and suggests considerations for fire management.

Effect of granulated wood ash fertilization on N2O emissions in boreal peat forests

NASA Astrophysics Data System (ADS)

Liimatainen, Maarit; Martikainen, Pertti J.; Hytönen, Jyrki; Maljanen, Marja

2016-04-01

Peatlands cover one third of the land surface area in Finland and over half of that are drained for forestry. Natural peatlands are either small sources of nitrous oxide (N2O) or they can also act as a sinks of N2O. When peatlands are drained, oxygen concentration in the peat increases, organic matter decomposition accelerates and N2O emissions may increase significantly, especially in nutrient rich peat soils. Hence drainage and land-use changes can have a big impact on N2O fluxes in peatlands. The annual consumption of wood chips is to be increased to 13.5 M m3 from the present 8.7 M m3 in Finland. This will also increase the amount of wood ash in the power plants. Wood ash contains considerable amounts of mineral nutrients but lacks nitrogen. Therefore, it has been used as a fertilizer in nitrogen rich peatland forests lacking other nutrients. Recycling of ash would also return the nutrients lost during biomass harvesting back to the forests. We studied the effects of granulated wood ash as a fertilizer in peat soils drained for forestry. Ash is nowadays granulated mainly to facilitate its handling and spreading. Granulation also stabilizes the ash decreasing the solubility of most of the nutrients and minimizing harmful effects of ash spread over the vegetation. Granulated wood ash increases soil pH less than loose ash. Drainage of peatland forests increases microbial activity in the soil which is furthermore intensified with the addition of ash promoting organic matter decomposition and possibly affecting N2O emissions. We studied the effect of granulated wood ash on N2O fluxes in three different peat forests in Finland in both field and laboratory experiments. In the field, N2O emissions were not affected by granulated wood ash fertilization but the soil respiration rate increased. However, in the laboratory studies we observed a clear decrease in N2O production due to wood ash addition, although changes in pH values were only minor. We studied what could explain this decrease in N2O production. Despite of the granulation process some nutrients (e.g. K, Na, B, S) still leach quickly from the ash in form of ions, which was observed as an increased electrical conductivity. Granulated ash contains a high concentration of sulfates and we created in the laboratory experiments with the addition of K2SO4 or (NH4)2SO4 similar decrease in N2O production as observed with the addition of granulated wood ash. Our results indicate that quickly leaching ions inhibit nitrification in peat. In the field experiments the same phenomena was not observed, probably due to leaching of the nutrients (ions) deeper into the soil and due to the competition of vegetation which outcompetes microbes for available nutrients. In conclusion, the use of granulated wood ash does not increase N2O emissions in boreal peat forests.

Co-firing of oil sludge with coal-water slurry in an industrial internal circulating fluidized bed boiler.

PubMed

Liu, Jianguo; Jiang, Xiumin; Zhou, Lingsheng; Wang, Hui; Han, Xiangxin

2009-08-15

Incineration has been proven to be an alternative for disposal of sludge with its unique characteristics to minimize the volume and recover energy. In this paper, a new fluidized bed (FB) incineration system for treating oil sludge is presented. Co-firing of oil sludge with coal-water slurry (CWS) was investigated in the new incineration system to study combustion characteristics, gaseous pollutant emissions and ash management. The study results show the co-firing of oil sludge with CWS in FB has good operating characteristic. CWS as an auxiliary fuel can flexibly control the dense bed temperatures by adjusting its feeding rate. All emissions met the local environmental requirements. The CO emission was less than 1 ppm or essentially zero; the emissions of SO(2) and NO(x) were 120-220 and 120-160 mg/Nm(3), respectively. The heavy metal analyses of the bottom ash and the fly ash by ICP/AES show that the combustion ashes could be recycled as soil for farming.

Emissions During Co-Firing of RDF-5 with Coal in a 22 t/h Steam Bubbling Fluidized Bed Boiler

NASA Astrophysics Data System (ADS)

Wan, Hou-Peng; Chen, Jia-Yuan; Juch, Ching-I.; Chang, Ying-Hsi; Lee, Hom-Ti

The co-firing of biomass and fossil fuel in the same power plant is one of the most important issues when promoting the utilization of renewable energy in the world. Recently, the co-firing of coal together with biomass fuel, such as "densified refuse derived fuel" (d-RDF or RDF-5) or RPF (refuse paper & plastic fuel) from waste, has been considered as an environmentally sound and economical approach to both waste remediation and energy production in the world. Because of itscomplex characteristics when compared to fossil fuel, potential problems, such as combustion system stability, the corrosion of heat transfer tubes, the qualities of the ash, and the emissionof pollutants, are major concerns when co-firing the biomass fuel with fossil fuel in a traditional boiler. In this study, co-firing of coal with RDF-5 was conducted in a 22t/h bubbling fluidized bed (BFB) steam boiler to investigate the feasibility of utilizing RDF-5 as a sustainable fuels in a commercial coal-fired steam BFB boiler. The properties of the fly ash, bottom ash, and the emission of pollutants are analyzed and discussed in this study.

Fire regimes, forest change, and self-organization in an old-growth mixed-conifer forest, Yosemite National Park, USA.

PubMed

Scholl, Andrew E; Taylor, Alan H

2010-03-01

Fire is recognized as a keystone process in dry mixed-conifer forests that have been altered by decades of fire suppression, Restoration of fire disturbance to these forests is a guiding principle of resource management in the U.S. National Park Service. Policy implementation is often hindered by a poor understanding of forest conditions before fire exclusion, the characteristics of forest changes since excluding fire, and the influence of topographic or self-organizing controls on forest structure. In this study the spatial and temporal characteristics of fire regimes and forest structure are reconstructed in a 2125-ha mixed-conifer forest. Forests were multi-aged, burned frequently at low severity and fire-return interval, and forest structure did not vary with slope aspect, elevation, or slope position. Fire exclusion has caused an increase in forest density and basal area and a compositional shift to shade-tolerant and fire-intolerant species. The median point fire-return interval and extent of a fire was 10 yr and 115 ha, respectively. The pre-Euro-American settlement fire rotation of 13 yr increased to 378 yr after 1905. The position of fire scars within tree rings indicates that 79% of fires burned in the midsummer to fall period. The spatial pattern of burns exhibited self-organizing behavior. Area burned was 10-fold greater when an area had not been burned by the previous fire. Fires were frequent and widespread, but patches of similar aged trees were < 0.2 ha, suggesting small fire-caused canopy openings. Managers need to apply multiple burns at short intervals for a sustained period to reduce surface fuels and create small canopy openings characteristic of the reference forest. By coupling explicit reference conditions with consideration of current conditions and projected climate change, management activities can balance restoration and risk management.

Three-year progression of emerald ash borer-induced decline and mortality in southeastern Michigan

Treesearch

Kamal J.K. Gandhi; Annemarie Smith; Robert P. Long; Robin A.J. Taylor; Daniel A. Herms

2008-01-01

We monitored the progression of ash (Fraxinus spp.) decline and mortality due to emerald ash borer (EAB), Agrilus planipennis, in 38 forest stands in the upper Huron River watershed region of southeastern Michigan from 2004-2007. Black ash (F. nigra), green ash (F. pennsylvanica), and white ash...

Examining Historical and Current Mixed-Severity Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America

PubMed Central

Odion, Dennis C.; Hanson, Chad T.; Arsenault, André; Baker, William L.; DellaSala, Dominick A.; Hutto, Richard L.; Klenner, Walt; Moritz, Max A.; Sherriff, Rosemary L.; Veblen, Thomas T.; Williams, Mark A.

2014-01-01

There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to “restore” forests to open, low-severity fire conditions may not align with historical reference conditions in most ponderosa pine and mixed-conifer forests of western North America. PMID:24498383

Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

PubMed

Odion, Dennis C; Hanson, Chad T; Arsenault, André; Baker, William L; Dellasala, Dominick A; Hutto, Richard L; Klenner, Walt; Moritz, Max A; Sherriff, Rosemary L; Veblen, Thomas T; Williams, Mark A

2014-01-01

There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in most ponderosa pine and mixed-conifer forests of western North America.

Water Level Controls on Sap Flux of Canopy Species in Black Ash Wetlands

Treesearch

Joseph Shannon; Matthew Van Grinsven; Joshua Davis; Nicholas Bolton; Nam Noh; Thomas Pypker; Randall Kolka

2018-01-01

Black ash (Fraxinus nigra Marsh.) exhibits canopy dominance in regularly inundated wetlands, suggesting advantageous adaptation. Black ash mortality due to emerald ash borer (Agrilus planipennis Fairmaire) will alter canopy composition and site hydrology. Retention of these forested wetlands requires understanding black ash...

White ash (Fraxinus americana) health in the Allegheny plateau region, Pennsylvania: Evaluating the relationship between FIA phase 3 crown variables and a categorical rating system

Treesearch

Alejandro A. Royo; Kathleen S. Knight; Jamie M. Himes; Ashley N. Will

2012-01-01

Following the detection of white ash (Fraxinus americana) decline in the Allegheny National Forest (ANF) of Pennsylvania, we established an intensified white ash monitoring network throughout the ANF. We rated crowns using both a categorical system as well as Forest Inventory and Analyses (FIA) Phase 3 measures of uncompacted live crown ratio,...

The Habitat Susceptibility of Bali Starling (Leucopsar rothschildi Stresemann> 1912) Based on Forest Fire Vulnerability Mappin in West Bali National Park

NASA Astrophysics Data System (ADS)

Pramatana, F.; Prasetyo, L. B.; Rushayati, S. B.

2017-10-01

Bali starling is an endemic and endangered species which tend to decrease of its population in the wild. West Bali National Park (WBNP) is the only habitat of bali starling, however it is threatened nowadays by forest fire. Understanding the sensitivity of habitat to forest & land fire is urgently needed. Geographic Information System (GIS) can be used for mapping the vulnerability of forest fire. This study aims to analyze the contributed factor of forest fire, to develop vulnerability level map of forest fire in WBNP, to estimate habitat vulnerability of bali starling. The variable for mapping forest fire in WBNP were road distance, village distance, land cover, NDVI, NDMI, surface temperature, and slope. Forest fire map in WBNP was created by scoring from each variable, and classified into four classes of forest fire vulnerability which are very low (9 821 ha), low (5 015.718 ha), middle (6 778.656 ha), and high (2 126.006 ha). Bali starling existence in the middle and high vulnerability forest fire class in WBNP, consequently the population and habitat of bali starling is a very vulnerable. Management of population and habitat of bali starling in WBNP must be implemented focus on forest fire impact.

Decree No. 849/988 of 14 December 1988 setting forth regulations on the prevention and combat of forest fires.

PubMed

1989-01-01

This Uruguayan Decree sets forth regulations on the prevention and fighting of forest fires. Among other things, it does the following: 1) requires all public and private organizations, as well as all persons, to assist personally in and provide vehicles, machines, and tools for the fighting of forest fires; 2) requires the owners of property containing forests to maintain instruction in fighting fires for an adequate number of employees; 3) requires all forests to be kept cleared of vegetation capable of spreading fires and to have fire walls; 4) requires owners of forests larger than 30 hectares in size to present to the Forest Directorate an annual plan for forest fire defense; and 5) requires owners of forests larger than 30 hectares in size to maintain specified equipment for fighting fires. Persons violating the provisions of this Decree are subject to fines.

Bottom ash test section evaluation Erwinville, LA.

DOT National Transportation Integrated Search

2009-02-01

Bottom ash is a by-product of the energy industry and the residual of burning coal in a kiln : firing process. Bottom ash is black and the consistency of coarse sand with gravel clinker : traces. The product is used in other states as embankment mate...

Fire ecology of forests and woodlands in Utah

Treesearch

Anne F. Bradley; Nonan V. Noste; William C. Fischer

1992-01-01

Provides information on fire as an ecological factor in forest habitat types, and in pinyon-juniper woodland and oak-maple brushland communities occurring in Utah. Identifies Fire Groups based on fire's role in forest succession. Describes forest fuels and suggests considerations for fire management.

Fire ecology of the forest habitat types of eastern Idaho and western Wyoming

Treesearch

Anne F. Bradley; William C. Fischer; Nonan V. Noste

1992-01-01

Provides information on fire as an ecological factor in the forest habitat types occurring in eastern Idaho and western Wyoming. Identifies Fire Groups based on fire's role in forest succession. Describes forest fuels and suggests considerations for fire management.

Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

NASA Astrophysics Data System (ADS)

Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

2016-06-01

Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

Impact of forest fires on particulate matter and ozone levels during the 2003, 2004 and 2005 fire seasons in Portugal.

PubMed

Martins, V; Miranda, A I; Carvalho, A; Schaap, M; Borrego, C; Sá, E

2012-01-01

The main purpose of this work is to estimate the impact of forest fires on air pollution applying the LOTOS-EUROS air quality modeling system in Portugal for three consecutive years, 2003-2005. Forest fire emissions have been included in the modeling system through the development of a numerical module, which takes into account the most suitable parameters for Portuguese forest fire characteristics and the burnt area by large forest fires. To better evaluate the influence of forest fires on air quality the LOTOS-EUROS system has been applied with and without forest fire emissions. Hourly concentration results have been compared to measure data at several monitoring locations with better modeling quality parameters when forest fire emissions were considered. Moreover, hourly estimates, with and without fire emissions, can reach differences in the order of 20%, showing the importance and the influence of this type of emissions on air quality. Copyright © 2011 Elsevier B.V. All rights reserved.

The relative importance of hydrophobicity in determining runoff-infiltration processes in burned forest soils

NASA Astrophysics Data System (ADS)

Wittenberg, Lea; Malkinson, Dan; Voogt, Annelies; Leska, Danny; Argaman, Eli; Keesstra, Saskia

2010-05-01

Wildfires induce fundamental changes to vegetation and soil structure/texture which conseqeuntly have major impacts on infiltration capacity, overland flow generation, runoff and sediment yields. The relative importance, however, of fire-induced soil water repellency (WR) on hydrological and erosional processes is somewhat controversial, partially, as the direct effects of soil WR in-situ field conditions have been difficult to isolate. It is generally accepted that hydrophobicity is caused by the formation of organic substances in forest soils, while burning is considered to enhance this process. Given the complex response of the soil-vegetation system to burning, soil WR is only one of several affecting soil hydrology. Other factors include the physical sealing of soils triggered by rain drops energy, the increase in soil erodibility due to changes in soil aggregates, and the role of the ash in sealing the burned surface. The degree and spatial distribution of WR burned varies considerably with fire severity, soil and vegetation type, soil moisture content and time since burning. Nevertheless, given the inverse relationship between soil moisture and hydrophobicity, the role of the latter in determining overland flow during wet winters when the soil is mostly inundated, is marginal. Following a 60 ha wildfire, which took place at the Pe'eram catchment during July 2009, we assessed the spatio-temporal distribution of WR in a burned Pinus halepensis forest. The site, located in the Upper Galille, Israel, was severely burned; the combustion removed all understory vegetation and burned down some of the trunks, leaving a thick layer of ash. The soils composed of reddish-brown clay loam forest soil and terra rossa on limestone bedrock, greyish light rendzina characterises the marl and chalk exposures. To consider the effect of distance from trees, in-situ hydrophobicity was assessed within a week, month and five months after the fire, using the WDPT test. Measurements were taken in concentric circles around the burned trees at two soil depths. We complemented this investigation by conducting a series of laboratory simulations. Non-burned soil was taken for laboratory analysis and rainfall simulations. Four treatment types were conducted: non-burned soil, non-burned soil + pine needles, burned soil without ash (300°C/15 min. after adding pine needles) and burned soil with the residue ash (300°C/15 min. after adding pine needles). Hydrophobicity was measured in all trays. Constant rainfall intensity of 30 mm/hr was simulated until terminal infiltration rates were reached. The experimental trays were oven dried and simulated again to imitate the effect of second rainstorm. Preliminary results indicate strong surface WR (60% >180s) at a distance of 1m and at the subsurface (50% >180s) directly by the trunk. In the control non-burned site stronger WR was found in proximity to the trunks. While in the burned sites extreme values (>300s) were apparent (15-35%) and correlated with distance from the trunk, no corresponding patterns were noticed in the control trees. The attempt to create homogeneous layer of WR under controlled laboratory conditions yielded a scattered pattern of repellency, similar to the field conditions. In contrast to expected, the bare soil and bare soil covered by needles exhibited the highest and lowest infiltration rates, respectively, while the burned hydrophobic soils demonstrated intermediate rates. It is thus suggested that in some soils, WR might enhance infiltration capacity by creating a complex mosaic of runoff-generating and runoff-absorbing micro-patches. In the experimental non-burned soil a rapid crusting of the surface provided lateral connectivity whilst the accumulation of litter and organic matter blanket the surface and enhance the vertical conductivity. To better understand the role of WR in generating hydrological response, it is required to consider the 3D 'sponge like' properties of the WR soils.

Fire and forest history at Mount Rushmore.

PubMed

Brown, Peter M; Wienk, Cody L; Symstad, Amy J

2008-12-01

Mount Rushmore National Memorial in the Black Hills of South Dakota is known worldwide for its massive sculpture of four of the United States' most respected presidents. The Memorial landscape also is covered by extensive ponderosa pine (Pinus ponderosa) forest that has not burned in over a century. We compiled dendroecological and forest structural data from 29 plots across the 517-ha Memorial and used fire behavior modeling to reconstruct the historical fire regime and forest structure and compare them to current conditions. The historical fire regime is best characterized as one of low-severity surface fires with occasional (> 100 years) patches (< 100 ha) of passive crown fire. We estimate that only approximately 3.3% of the landscape burned as crown fire during 22 landscape fire years (recorded at > or = 25% of plots) between 1529 and 1893. The last landscape fire was in 1893. Mean fire intervals before 1893 varied depending on spatial scale, from 34 years based on scar-to-scar intervals on individual trees to 16 years between landscape fire years. Modal fire intervals were 11-15 years and did not vary with scale. Fire rotation (the time to burn an area the size of the study area) was estimated to be 30 years for surface fire and 800+ years for crown fire. The current forest is denser and contains more small trees, fewer large trees, lower canopy base heights, and greater canopy bulk density than a reconstructed historical (1870) forest. Fire behavior modeling using the NEXUS program suggests that surface fires would have dominated fire behavior in the 1870 forest during both moderate and severe weather conditions, while crown fire would dominate in the current forest especially under severe weather. Changes in the fire regime and forest structure at Mount Rushmore parallel those seen in ponderosa pine forests from the southwestern United States. Shifts from historical to current forest structure and the increased likelihood of crown fire justify the need for forest restoration before a catastrophic wildfire occurs and adversely impacts the ecological and aesthetic setting of the Mount Rushmore sculpture.

[Effects of Chinese prickly ash orchard on soil organic carbon mineralization and labile organic carbon in karst rocky desertification region of Guizhou province].

PubMed

Zhang, Wen-Juan; Liao, Hong-Kai; Long, Jian; Li, Juan; Liu, Ling-Fei

2015-03-01

Taking 5-year-old Chinese prickly ash orchard (PO-5), 17-year-old Chinese prickly ash orchard (PO- 17), 30-year-old Chinese prickly ash orchard (PO-30) and the forest land (FL, about 60 years) in typical demonstration area of desertification control test in southwestern Guizhou as our research objects, the aim of this study using a batch incubation experiment was to research the mineralization characteristics of soil organic carbon and changes of the labile soil organic carbon contents at different depths (0-15 cm, 15-30 cm, and 30-50 cm). The results showed that: the cumulative mineralization amounts of soil organic carbon were in the order of 30-year-old Chinese prickly ash orchard, the forest land, 5-year-old Chinese prickly ash orchard and 17-year-old Chinese prickly ash orchard at corresponding depth. Distribution ratios of CO2-C cumulative mineralization amount to SOC contents were higher in Chinese prickly ash orchards than in forest land at each depth. Cultivation of Chinese prickly ash in long-term enhanced the mineralization of soil organic carbon, and decreased the stability of soil organic carbon. Readily oxidized carbon and particulate organic carbon in forest land soils were significantly more than those in Chinese prickly ash orchards at each depth (P < 0.05). With the increasing times of cultivation of Chinese prickly ash, the contents of readily oxidized carbon and particulate organic carbon first increased and then declined at 0-15 cm and 15-30 cm depth, respectively, but an opposite trend was found at 30-50 cm depth. At 0-15 cm and 15-30 cm, cultivation of Chinese prickly ash could be good for improving the contents of labile soil organic carbon in short term, but it was not conducive in long-term. In this study, we found that cultivation of Chinese prickly ash was beneficial for the accumulation of labile organic carbon at the 30-50 cm depth.

Fire ecology of Montana forest habitat types east of the Continental Divide

Treesearch

William C. Fischer; Bruce D. Clayton

1983-01-01

Provides information on fire as an ecological factor for forest habitat types occurring east of the Continental Divide in Montana. Identifies "Fire Groups" of habitat types based on fire's role in forest succession. Describes forest fuels and suggests considerations for fire management.

Mixed-severity fire history at a forest-grassland ecotone in west central British Columbia, Canada.

PubMed

Harvey, Jill E; Smith, Dan J; Veblen, Thomas T

2017-09-01

This study examines spatially variable stand structure and fire-climate relationships at a low elevation forest-grassland ecotone in west central British Columbia, Canada. Fire history reconstructions were based on samples from 92 fire-scarred trees and stand demography from 27 plots collected over an area of about 7 km 2 . We documented historical chronologies of widespread fires and localized grassland fires between AD 1600 and 1900. Relationships between fire events, reconstructed values of the Palmer Drought Severity Index, and annual precipitation were examined using superposed epoch and bivariate event analyses. Widespread fires occurred during warm, dry years and were preceded by multiple anomalously dry, warm years. Localized fires that affected only grassland-proximal forests were more frequent than widespread fires. These localized fires showed a lagged, positive relationship with wetter conditions. The landscape pattern of forest structure provided further evidence of complex fire activity with multiple plots shown to have experienced low-, mixed-, and/or high-severity fires over the last four centuries. We concluded that this forest-grassland ecotone was characterized by fires of mixed severity, dominated by frequent, low-severity fires punctuated by widespread fires of moderate to high severity. This landscape-level variability in fire-climate relationships and patterns in forest structure has important implications for fire and grassland management in west central British Columbia and similar environments elsewhere. Forest restoration techniques such as prescribed fire and thinning are oftentimes applied at the forest-grassland ecotone on the basis that historically high frequency, low-severity fires defined the character of past fire activity. This study provides forest managers and policy makers with important information on mixed-severity fire activity at a low elevation forest-grassland ecotone, a crucial prerequisite for the effective management of these complex ecosystems. © 2017 by the Ecological Society of America.

Influence of landscape structure, topography, and forest type on spatial variation in historical fire regimes, central Oregon, USA

USGS Publications Warehouse

Merschel, Andrew; Heyerdahl, Emily K.; Spies, Thomas A; Loehman, Rachel A.

2018-01-01

Context In the interior Northwest, debate over restoring mixed-conifer forests after a century of fire exclusion is hampered by poor understanding of the pattern and causes of spatial variation in historical fire regimes. Objectives To identify the roles of topography, landscape structure, and forest type in driving spatial variation in historical fire regimes in mixed-conifer forests of central Oregon. Methods We used tree rings to reconstruct multicentury fire and forest histories at 105 plots over 10,393 ha. We classified fire regimes into four types and assessed whether they varied with topography, the location of fuel-limited pumice basins that inhibit fire spread, and an updated classification of forest type. Results We identified four fire-regime types and six forest types. Although surface fires were frequent and often extensive, severe fires were rare in all four types. Fire regimes varied with some aspects of topography (elevation), but not others (slope or aspect) and with the distribution of pumice basins. Fire regimes did not strictly co-vary with mixed-conifer forest types. Conclusions Our work reveals the persistent influence of landscape structure on spatial variation in historical fire regimes and can help inform discussions about appropriate restoration of fire-excluded forests in the interior Northwest. Where the goal is to restore historical fire regimes at landscape scales, managers may want to consider the influence of topoedaphic and vegetation patch types that could affect fire spread and ignition frequency.

Historical dominance of low-severity fire in dry and wet mixed-conifer forest habitats of the endangered terrestrial Jemez Mountains salamander (Plethodon neomexicanus)

USGS Publications Warehouse

Margolis, Ellis; Malevich, Steven B.

2016-01-01

Anthropogenic alteration of ecosystem processes confounds forest management and conservation of rare, declining species. Restoration of forest structure and fire hazard reduction are central goals of forest management policy in the western United States, but restoration priorities and treatments have become increasingly contentious. Numerous studies have documented changes in fire regimes, forest stand structure and species composition following a century of fire exclusion in dry, frequent-fire forests of the western U.S. (e.g., ponderosa pine and dry mixed-conifer). In contrast, wet mixed-conifer forests are thought to have historically burned infrequently with mixed- or high-severity fire—resulting in reduced impacts from fire exclusion and low restoration need—but data are limited. In this study we quantified the current forest habitat of the federally endangered, terrestrial Jemez Mountains salamander (Plethodon neomexicanus) and compared it to dendroecological reconstructions of historical habitat (e.g., stand structure and composition), and fire regime parameters along a gradient from upper ponderosa pine to wet mixed-conifer forests. We found that current fire-free intervals in Jemez Mountains salamander habitat (116–165 years) are significantly longer than historical intervals, even in wet mixed-conifer forests. Historical mean fire intervals ranged from 10 to 42 years along the forest gradient. Low-severity fires were historically dominant across all forest types (92 of 102 fires). Although some mixed- or highseverity fire historically occurred at 67% of the plots over the last four centuries, complete mortality within 1.0 ha plots was rare, and asynchronous within and among sites. Climate was an important driver of temporal variability in fire severity, such that mixed- and high-severity fires were associated with more extreme drought than low-severity fires. Tree density in dry conifer forests historically ranged from open (90 trees/ha) to moderately dense (400 trees/ha), but has doubled on average since fire exclusion. Infill of fire-sensitive tree species has contributed to the conversion of historically dry mixedconifer to wet mixed-conifer forest. We conclude that low-severity fire, which has been absent for over a century, was a critical ecosystem process across the forest gradient in Jemez Mountains salamander habitat, and thus is an important element of ecosystem restoration, resilience, and rare species recovery.

Effects of forest fire and logging on forest degradation in Mongolia

Treesearch

Yeong Dae Park; Don Koo Lee; Jamsran Tsogtbaatar; John A. Stanturf

2010-01-01

Forests in Mongolia have been severely degraded by forest fire and exploitive logging. This study investigate changes in vegetation and soil properties after forest fire or clearfelling. Microclimate conditions such as temperature and relative humidity (RH) changed drastically after forest fire or logging; temperature increased 1.6-1.7 ºC on average, whereas...

Utilization of open pit burned household waste ash--a feasibility study in Dhaka.

PubMed

Haque, Md Obaidul; Sharif, Ahmed

2014-05-01

Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.

Changing Weather Extremes Call for Early Warning of Potential for Catastrophic Fire

NASA Astrophysics Data System (ADS)

Boer, Matthias M.; Nolan, Rachael H.; Resco De Dios, Víctor; Clarke, Hamish; Price, Owen F.; Bradstock, Ross A.

2017-12-01

Changing frequencies of extreme weather events and shifting fire seasons call for enhanced capability to forecast where and when forested landscapes switch from a nonflammable (i.e., wet fuel) state to the highly flammable (i.e., dry fuel) state required for catastrophic forest fires. Current forest fire danger indices used in Europe, North America, and Australia rate potential fire behavior by combining numerical indices of fuel moisture content, potential rate of fire spread, and fire intensity. These numerical rating systems lack the physical basis required to reliably quantify forest flammability outside the environments of their development or under novel climate conditions. Here, we argue that exceedance of critical forest flammability thresholds is a prerequisite for major forest fires and therefore early warning systems should be based on a reliable prediction of fuel moisture content plus a regionally calibrated model of how forest fire activity responds to variation in fuel moisture content. We demonstrate the potential of this approach through a case study in Portugal. We use a physically based fuel moisture model with historical weather and fire records to identify critical fuel moisture thresholds for forest fire activity and then show that the catastrophic June 2017 forest fires in central Portugal erupted shortly after fuels in the region dried out to historically unprecedented levels.

Forest Fire Advanced System Technology (FFAST): A Conceptual Design for Detection and Mapping

Treesearch

J. David Nichols; John R. Warren

1987-01-01

The Forest Fire Advanced System Technology (FFAST) project is developing a data system to provide near-real-time forest fire information to fire management at the fire Incident Command Post (ICP). The completed conceptual design defined an integrated forest fire detection and mapping system that is based upon technology available in the 1990's. System component...

Relation of weather forecasts to the prediction of dangerous forest fire conditions

Treesearch

R. H. Weidman

1923-01-01

The purpose of predicting dangerous forest-fire conditions, of course, is to reduce the great cost and damage caused by forest fires. In the region of Montana and northern Idaho alone the average cost to the United States Forest Service of fire protection and suppression is over $1,000,000 a year. Although the causes of forest fires will gradually be reduced by...

Biofouling attractants from a brown marine alga Ecklonia cava.

PubMed

Sidharthan, M; Viswanadh, G S; Kim, Kyoung Ho; Kim, Hyuk Jun; Shin, H W

2007-04-01

In recent years, industrial pollutants and the mountain forest fire ashes released into seawater cause damage to the marine environment, mainly it reduces the algal productivity in the inter tidal region. To get recover from the stress due to pollutants and to increase the growth and development of biofouling algae (benthic organisms), Ecklonia cava extract was investigated for its biofouling attracting efficiency. Bioactive guided fractions of E. cava extract derived from column chromatography were tested against spore attachment of a fouling alga, Ulva pertusa. Fraction B showed increased spore attachment rate with a maximum of 92 +/- 5%. This fraction was further analysed on HPLC, GC-Mass and NMR, deduced as pentadecanoic acid.

Numerical study of propagation of forest fires in the presence of fire breaks using an averaged setting

NASA Astrophysics Data System (ADS)

Marzaeva, S. I.; Galtseva, O. V.

2018-05-01

The forest fires spread in the pine forests have been numerically simulated using a three-dimensional mathematical model. The model was integrated with respect to the vertical coordinate because horizontal sizes of forest are much greater than the heights of trees. In this paper, the assignment and theoretical investigations of the problems of crown forest fires spread pass the firebreaks were carried out. In this context, a study ( mathematical modeling) of the conditions of forest fire spreading that would make it possible to obtain a detailed picture of the change in the temperature and component concentration fields with time, and determine as well as the limiting condition of fire propagation in forest with these fire breaks.

Environmental benefits of using magnesium carbonate minerals as new wildfire retardants instead of commercially available, phosphate-based compounds.

PubMed

Liodakis, S; Tsoukala, M

2010-10-01

A serial batch leaching experiment has been carried out to evaluate the release of elements from the ash of Pinus halepensis needles burned under two test conditions-with and without treatment of the forest species with the carbonate minerals (huntite and hydromagnesite) in aqueous solution (pH 6). The ash (before and after leaching) and leachates were analyzed using atomic absorption spectroscopy and X-ray diffraction. Compared with data from samples treated with the commercially available, phosphate-based fire retardant diammonium phosphate (DAP), we found that use of huntite or hydromagnesite was much more successful in obstructing the release of the toxic elements present in the ash, probably because of the alkaline conditions resulting from decomposition of the minerals during burning. In contrast, DAP tended to be more able to facilitate the extraction of some toxic metals (e.g., Zn, Cu, Mn), probably because of the acidic conditions resulting from its decomposition to phosphoric acid. Data from this study thus lend strong support to the use of magnesium carbonate minerals as new wildfire retardants, because they were shown to be more friendly to the environment (e.g., soil, ground, and underground water streams) than those currently in use (e.g., phosphate or sulfate salt type).

Screening of heavy metal containing waste types for use as raw material in Arctic clay-based bricks.

PubMed

Belmonte, Louise Josefine; Ottosen, Lisbeth M; Kirkelund, Gunvor Marie; Jensen, Pernille Erland; Vestbø, Andreas Peter

2016-11-10

In the vulnerable Arctic environment, the impact of especially hazardous wastes can have severe consequences and the reduction and safe handling of these waste types are therefore an important issue. In this study, two groups of heavy metal containing particulate waste materials, municipal solid waste incineration (MSWI) fly and bottom ashes and mine tailings (i.e., residues from the mineral resource industry) from Greenland were screened in order to determine their suitability as secondary resources in clay-based brick production. Small clay discs, containing 20 or 40% of the different particulate waste materials, were fired and material properties and heavy metal leaching tests were conducted before and after firing. Remediation techniques (washing in distilled water and electrodialytical treatment) applied to the fly ash reduced leaching before firing. The mine tailings and bottom ash brick discs obtained satisfactory densities (1669-2007 kg/m 3 ) and open porosities (27.9-39.9%). In contrast, the fly ash brick discs had low densities (1313-1578 kg/m 3 ) and high open porosities (42.1-51. %). However, leaching tests on crushed brick discs revealed that heavy metals generally became more available after firing for all the investigated materials and that further optimisation is therefore necessary prior to incorporation in bricks.

Mexican forest fires and their decadal variations

NASA Astrophysics Data System (ADS)

Velasco Herrera, Graciela

2016-11-01

A high forest fire season of two to three years is regularly observed each decade in Mexican forests. This seems to be related to the presence of the El Niño phenomenon and to the amount of total solar irradiance. In this study, the results of a multi-cross wavelet analysis are reported based on the occurrence of Mexican forest fires, El Niño and the total solar irradiance for the period 1970-2014. The analysis shows that Mexican forest fires and the strongest El Niño phenomena occur mostly around the minima of the solar cycle. This suggests that the total solar irradiance minima provide the appropriate climatological conditions for the occurrence of these forest fires. The next high season for Mexican forest fires could start in the next solar minimum, which will take place between the years 2017 and 2019. A complementary space analysis based on MODIS active fire data for Mexican forest fires from 2005 to 2014 shows that most of these fires occur in cedar and pine forests, on savannas and pasturelands, and in the central jungles of the Atlantic and Pacific coasts.

The spatial distribution of riparian ash: implications for the dispersal of the emerald ash borer

Treesearch

Susan J. Crocker; W. Keith Moser; Mark H. Hansen; Mark D. Nelson

2007-01-01

A pilot study to assess riparian ash connectivity and its implications for emerald ash borer dispersal was conducted in three subbasins in Michigan's Southern Lower Peninsula. Forest Inventory and Analysis data were used to estimate ash biomass. The nineteen percent of plots in riparian physiographic classes contained 40 percent of ash biomass. Connectivity of...

Meteorological factors in the Quartz Creek forest fire

Treesearch

H. T. Gisborne

1927-01-01

It is not often that a large forest fire occurs conveniently near a weather station specially equipped for measuring forest-fire weather. The 13,000-acre Quartz Creek fire on the Kaniksu National Forest during the summer of 1936 was close enough to the Priest River Experimental Forest of the Northern Rocky Mountain Forest Experiment Station for the roar of the flumes...

Understorey fire frequency and the fate of burned forests in southern Amazonia.

PubMed

Morton, D C; Le Page, Y; DeFries, R; Collatz, G J; Hurtt, G C

2013-06-05

Recent drought events underscore the vulnerability of Amazon forests to understorey fires. The long-term impact of fires on biodiversity and forest carbon stocks depends on the frequency of fire damages and deforestation rates of burned forests. Here, we characterized the spatial and temporal dynamics of understorey fires (1999-2010) and deforestation (2001-2010) in southern Amazonia using new satellite-based estimates of annual fire activity (greater than 50 ha) and deforestation (greater than 10 ha). Understorey forest fires burned more than 85 500 km(2) between 1999 and 2010 (2.8% of all forests). Forests that burned more than once accounted for 16 per cent of all understorey fires. Repeated fire activity was concentrated in Mato Grosso and eastern Pará, whereas single fires were widespread across the arc of deforestation. Routine fire activity in Mato Grosso coincided with annual periods of low night-time relative humidity, suggesting a strong climate control on both single and repeated fires. Understorey fires occurred in regions with active deforestation, yet the interannual variability of fire and deforestation were uncorrelated, and only 2.6 per cent of forests that burned between 1999 and 2008 were deforested for agricultural use by 2010. Evidence from the past decade suggests that future projections of frontier landscapes in Amazonia should separately consider economic drivers to project future deforestation and climate to project fire risk.

Understorey fire frequency and the fate of burned forests in southern Amazonia

PubMed Central

Morton, D. C.; Le Page, Y.; DeFries, R.; Collatz, G. J.; Hurtt, G. C.

2013-01-01

Recent drought events underscore the vulnerability of Amazon forests to understorey fires. The long-term impact of fires on biodiversity and forest carbon stocks depends on the frequency of fire damages and deforestation rates of burned forests. Here, we characterized the spatial and temporal dynamics of understorey fires (1999–2010) and deforestation (2001–2010) in southern Amazonia using new satellite-based estimates of annual fire activity (greater than 50 ha) and deforestation (greater than 10 ha). Understorey forest fires burned more than 85 500 km2 between 1999 and 2010 (2.8% of all forests). Forests that burned more than once accounted for 16 per cent of all understorey fires. Repeated fire activity was concentrated in Mato Grosso and eastern Pará, whereas single fires were widespread across the arc of deforestation. Routine fire activity in Mato Grosso coincided with annual periods of low night-time relative humidity, suggesting a strong climate control on both single and repeated fires. Understorey fires occurred in regions with active deforestation, yet the interannual variability of fire and deforestation were uncorrelated, and only 2.6 per cent of forests that burned between 1999 and 2008 were deforested for agricultural use by 2010. Evidence from the past decade suggests that future projections of frontier landscapes in Amazonia should separately consider economic drivers to project future deforestation and climate to project fire risk. PMID:23610169

Fire ecology of the forest habitat types of northern Idaho

Treesearch

Jane Kapler Smith; William C. Fischer

1997-01-01

Provides information on fire ecology in forest habitat and community types occurring in northern Idaho. Identifies fire groups based on presettlement fire regimes and patterns of succession and stand development after fire. Describes forest fuels and suggests considerations for fire management.

Southwestern Oregon's Biscuit Fire: An Analysis of Forest Resources, Fire Severity, and Fire Hazard

Treesearch

David L. Azuma; Glenn A. Christensen

2005-01-01

This study compares pre-fire field inventory data (collected from 1993 to 1997) in relation to post-fire mapped fire severity classes and the Fire and Fuels Extension of the Forest Vegetation Simulator growth and yield model measures of fire hazard for the portion of the Siskiyou National Forest in the 2002 Biscuit fire perimeter of southwestern Oregon. Post-fire...

Fire ecology of the forest habitat types of central Idaho

Treesearch

M. F. Crane; William C. Fischer

1986-01-01

Discusses fire as an ecological factor for forest habitat types occurring in central Idaho. Identifies "Fire Groups" of habitat types based on fire's role in forest succession. Considerations for fire management are suggested.

Effect of pond ash on pen surface properties

USDA-ARS?s Scientific Manuscript database

Maintaining adequate feedlot pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen series with dimensio...

Short- and long-term effects of fire on carbon in US dry temperate forest systems

USGS Publications Warehouse

Hurteau, Matthew D.; Brooks, Matthew L.

2011-01-01

Forests sequester carbon from the atmosphere, and in so doing can mitigate the effects of climate change. Fire is a natural disturbance process in many forest systems that releases carbon back to the atmosphere. In dry temperate forests, fires historically burned with greater frequency and lower severity than they do today. Frequent fires consumed fuels on the forest floor and maintained open stand structures. Fire suppression has resulted in increased understory fuel loads and tree density; a change in structure that has caused a shift from low- to high-severity fires. More severe fires, resulting in greater tree mortality, have caused a decrease in forest carbon stability. Fire management actions can mitigate the risk of high-severity fires, but these actions often require a trade-off between maximizing carbon stocks and carbon stability. We discuss the effects of fire on forest carbon stocks and recommend that managing forests on the basis of their specific ecologies should be the foremost goal, with carbon sequestration being an ancillary benefit. ?? 2011 by American Institute of Biological Sciences. All rights reserved.

Satellite Analysis of the Severe 1987 Forest Fires in Northern China and Southeastern Siberia

NASA Technical Reports Server (NTRS)

Cahoon, Donald R., Jr.; Stocks, Brian J.; Levine, Joel S.; Cofer, Wesley R., III; Pierson, Joseph M.

1994-01-01

Meteorological conditions, extremely conducive to fire development and spread in the spring of 1987, resulted in forest fires burning over extremely large areas in the boreal forest zone in northeastern China and the southeastern region of Siberia. The great China fire, one of the largest and most destructive forest fires in recent history, occurred during this period in the Heilongjiang Province of China. Satellite imagery is used to examine the development and areal distribution of 1987 forest fires in this region. Overall trace gas emissions to the atmosphere from these fires are determined using a satellite-derived estimate of area burned in combination with fuel consumption figures and carbon emission ratios for boreal forest fires.

Satellite analysis of the severe 1987 forest fires in northern China and southeastern Siberia

NASA Technical Reports Server (NTRS)

Cahoon, Donald R, Jr.; Stocks, Brian J.; Levine, Joel S.; Cofer, Wesley R., III; Pierson, Joseph M.

1994-01-01

Meteorological conditions, extremely conducive to fire development and spread in the spring of 1987, resulted in forest fires burning over extremely large areas in the boreal forest zone in northeastern China and the southeastern region of Siberia. The great China fire, one of the largest and most destructive forest fires in recent history, occurred during this period in the Heilongjiang Province of China. Satellite imagery is used to examine the development and areal distribution of 1987 forest fires in this region. Overall trace gas emissions to the atmosphere from these fires are determined using a satellite-derived estimate of area burned in combination with fuel consumption figures and carbon emission ratios for boreal forest fires.

An Assessment of Worldview-2 Imagery for the Classification Of a Mixed Deciduous Forest

NASA Astrophysics Data System (ADS)

Carter, Nahid

Remote sensing provides a variety of methods for classifying forest communities and can be a valuable tool for the impact assessment of invasive species. The emerald ash borer (Agrilus planipennis) infestation of ash trees (Fraxinus) in the United States has resulted in the mortality of large stands of ash throughout the Northeast. This study assessed the suitability of multi-temporal Worldview-2 multispectral satellite imagery for classifying a mixed deciduous forest in Upstate New York. Training sites were collected using a Global Positioning System (GPS) receiver, with each training site consisting of a single tree of a corresponding class. Six classes were collected; Ash, Maple, Oak, Beech, Evergreen, and Other. Three different classifications were investigated on four data sets. A six class classification (6C), a two class classification consisting of ash and all other classes combined (2C), and a merging of the ash and maple classes for a five class classification (5C). The four data sets included Worldview-2 multispectral data collection from June 2010 (J-WV2) and September 2010 (S-WV2), a layer stacked data set using J-WV2 and S-WV2 (LS-WV2), and a reduced data set (RD-WV2). RD-WV2 was created using a statistical analysis of the processed and unprocessed imagery. Statistical analysis was used to reduce the dimensionality of the data and identify key bands to create a fourth data set (RD-WV2). Overall accuracy varied considerably depending upon the classification type, but results indicated that ash was confused with maple in a majority of the classifications. Ash was most accurately identified using the 2C classification and RD-WV2 data set (81.48%). A combination of the ash and maple classes yielded an accuracy of 89.41%. Future work should focus on separating the ash and maple classifiers by using data sources such as hyperspectral imagery, LiDAR, or extensive forest surveys.

Spatial patterns and controls on historical fire regimes and forest structure in the Klamath Mountains

Treesearch

Alan H. Taylor; Carl N. Skinner

2003-01-01

Fire exclusion in mixed conifer forests has increased the risk of fire due to decades of fuel accumulation. Restoration of fire into altered forests is a challenge because of a poor understanding of the spatial and temporal dynamics of fire regimes. In this study the spatial and temporal characteristics of fire regimes and forest age structure are reconstructed in a...

Fuel variability following wildfire in forests with mixed severity fire regimes, Cascade Range, USA

Treesearch

Jessica L. Hudec; David L. Peterson

2012-01-01

Fire severity influences post-burn structure and composition of a forest and the potential for a future fire to burn through the area. The effects of fire on forests with mixed severity fire regimes are difficult to predict and interpret because the quantity, structure, and composition of forest fuels vary considerably. This study examines the relationship between fire...

Changing patterns of fire occurrence in proximity to forest edges, roads and rivers between NW Amazonian countries

NASA Astrophysics Data System (ADS)

Armenteras, Dolors; Barreto, Joan Sebastian; Tabor, Karyn; Molowny-Horas, Roberto; Retana, Javier

2017-06-01

Tropical forests in NW Amazonia are highly threatened by the expansion of the agricultural frontier and subsequent deforestation. Fire is used, both directly and indirectly, in Brazilian Amazonia to propagate deforestation and increase forest accessibility. Forest fragmentation, a measure of forest degradation, is also attributed to fire occurrence in the tropics. However, outside the Brazilian Legal Amazonia the role of fire in increasing accessibility and forest fragmentation is less explored. In this study, we compared fire regimes in five countries that share this tropical biome in the most north-westerly part of the Amazon Basin (Venezuela, Colombia, Ecuador, Peru and Brazil). We analysed spatial differences in the timing of peak fire activity and in relation to proximity to roads and rivers using 12 years of MODIS active fire detections. We also distinguished patterns of fire in relation to forest fragmentation by analysing fire distance to the forest edge as a measure of fragmentation for each country. We found significant hemispheric differences in peak fire occurrence with the highest number of fires in the south in 2005 vs. 2007 in the north. Despite this, both hemispheres are equally affected by fire. We also found difference in peak fire occurrence by country. Fire peaked in February in Colombia and Venezuela, whereas it peaked in September in Brazil and Peru, and finally Ecuador presented two fire peaks in January and October. We confirmed the relationship between fires and forest fragmentation for all countries and also found significant differences in the distance between the fire and the forest edge for each country. Fires were associated with roads and rivers in most countries. These results can inform land use planning at the regional, national and subnational scales to minimize the contribution of road expansion and subsequent access to the Amazonian natural resources to fire occurrence and the associated deforestation and carbon emissions.

A second-order impact model for forest fire regimes.

PubMed

Maggi, Stefano; Rinaldi, Sergio

2006-09-01

We present a very simple "impact" model for the description of forest fires and show that it can mimic the known characteristics of wild fire regimes in savannas, boreal forests, and Mediterranean forests. Moreover, the distribution of burned biomasses in model generated fires resemble those of burned areas in numerous large forests around the world. The model has also the merits of being the first second-order model for forest fires and the first example of the use of impact models in the study of ecosystems.

Modeling the Effects of Fire Frequency and Severity on Forests in the Northwestern United States

USGS Publications Warehouse

Busing, Richard T.; Solomon, Allen M.

2006-01-01

This study used a model of forest dynamics (FORCLIM) and actual forest survey data to demonstrate the effects of various fire regimes on different forest types in the Pacific Northwest. We examined forests in eight ecoregions ranging from wet coastal forests dominated by Pseudotsuga menziesii and other tall conifers to dry interior forests dominated by Pinus ponderosa. Fire effects simulated as elevated mortality of trees based on their species and size did alter forest structure and species composition. Low frequency fires characteristic of wetter forests (return interval >200 yr) had minor effects on composition. When fires were severe, they tended to reduce total basal area with little regard to species differences. High frequency fires characteristic of drier forests (return interval <30 yr) had major effects on species composition and on total basal area. Typically, they caused substantial reductions in total basal area and shifts in dominance toward highly fire tolerant species. With the addition of fire, simulated basal areas averaged across ecoregions were reduced to levels approximating observed basal areas.

Assessment of Post Forest Fire Landslides in Uttarakhand Himalaya, India

NASA Astrophysics Data System (ADS)

Sharma, N.; Singh, R. B.

2017-12-01

According to Forest Survey of India-State Forest Report (2015), the total geographical area of Uttarakhand is 53, 483 covers km2 out of which 24,402 km2 area covers under total forest covers. As noticed during last week of April, 2016 forest of Uttarakhand mountains was gutted down due to major incidences of fire. This incident caused huge damage to different species of flora-fauna, human being, livestock, property and destruction of mountain ecosystem. As per media reports, six people were lost their lives and recorded several charred carcasses of livestock's due to this incident. The forest fire was affected the eleven out of total thirteen districts which roughly covers the 0.2% (approx.) of total vegetation covers.The direct impact of losses are easy to be estimated but indirect impacts of this forest fire are yet to be occurred. The threat of post Forest fire induced landslides during rainfall is themain concern. Since, after forest fire top soil and rocks are loose due to loss of vegetation as binding and protecting agent against rainfall. Therefore, the pore water pressure and weathering will be very high during rainy season which can cause many landslides in regions affected by forest fire. The demarcation of areas worse affected by forest fire is necessary for issuing alerts to habitations and important infrastructures. These alerts will be based upon region specific probable rainfall forecasting through Indian Meteorological Department (IMD). The main objective is to develop a tool for detecting early forest fire and to create awareness amongst mountain community, researchers and concerned government agencies to take an appropriate measures to minimize the incidences of Forest fire and impact of post forest fire landslides in future through implementation of sustainable mountain strategy.

Estimation of Wild Fire Risk Area based on Climate and Maximum Entropy in Korean Peninsular

NASA Astrophysics Data System (ADS)

Kim, T.; Lim, C. H.; Song, C.; Lee, W. K.

2015-12-01

The number of forest fires and accompanying human injuries and physical damages has been increased by frequent drought. In this study, forest fire danger zone of Korea is estimated to predict and prepare for future forest fire hazard regions. The MaxEnt (Maximum Entropy) model is used to estimate the forest fire hazard region which estimates the probability distribution of the status. The MaxEnt model is primarily for the analysis of species distribution, but its applicability for various natural disasters is getting recognition. The detailed forest fire occurrence data collected by the MODIS for past 5 years (2010-2014) is used as occurrence data for the model. Also meteorology, topography, vegetation data are used as environmental variable. In particular, various meteorological variables are used to check impact of climate such as annual average temperature, annual precipitation, precipitation of dry season, annual effective humidity, effective humidity of dry season, aridity index. Consequently, the result was valid based on the AUC(Area Under the Curve) value (= 0.805) which is used to predict accuracy in the MaxEnt model. Also predicted forest fire locations were practically corresponded with the actual forest fire distribution map. Meteorological variables such as effective humidity showed the greatest contribution, and topography variables such as TWI (Topographic Wetness Index) and slope also contributed on the forest fire. As a result, the east coast and the south part of Korea peninsula were predicted to have high risk on the forest fire. In contrast, high-altitude mountain area and the west coast appeared to be safe with the forest fire. The result of this study is similar with former studies, which indicates high risks of forest fire in accessible area and reflects climatic characteristics of east and south part in dry season. To sum up, we estimated the forest fire hazard zone with existing forest fire locations and environment variables and had meaningful result with artificial and natural effect. It is expected to predict future forest fire risk with future climate variables as the climate changes.

Chemical composition and physical properties of filter fly ashes from eight grate-fired biomass combustion plants.

PubMed

Lanzerstorfer, Christof

2015-04-01

For the handling, treatment and utilization of fly ash from biomass combustion its chemical composition and physical properties are important. In this study eight filter fly ashes from different grate-fired biomass combustion plants were investigated. In fly ash from straw combustion high concentrations of (K) were found, whereas in the fly ash from wood combustion the concentrations of Ca and Mg were higher. The average concentration of PO4(3-) was similar in both types of fly ashes. In all wood fly ashes some measured heavy metal concentrations were above the limits for utilization. The straw fly ashes were much less contaminated and can be utilized. For wood fly ash most parameters showed little variation, except from one fly ash where the dust pre-separator is in poor condition. The average values were: mass median diameter 4.3±0.8 μm, spread of particle size distribution 19±11, particle density 2620±80 kg/m3 and angle of repose 50°±1°. The density of the straw fly ashes is lower (2260±80 kg/m3) and the spread of the size distribution is higher (72±24). For one straw combustion fly ash the values of the mass median diameter and the angle of repose were similar to the values of wood combustion fly ash, for the other straw fly ash the values differed considerably. While the particle size of this fly ash was much smaller, surprisingly the angle of repose was also lower. This can be attributed to the formation of small agglomerates in this fly ash, which were not disintegrated without a certain stress. Copyright © 2015. Published by Elsevier B.V.

Assessment of forest fire impacts and emissions in the European Union based on the European forest fire information system

Treesearch

Paulo Barbosa; Andrea Camia; Jan Kucera; Giorgio Libertá; Ilaria Palumbo; Jesus San-Miguel-Ayanz; Guido Schmuck

2009-01-01

An analysis on the number of forest fires and burned area distribution as retrieved by the European Forest Fire Information System (EFFIS) database is presented. On average, from 2000 to 2005 about...

Natural and social factors influencing forest fire occurrence at a local spatial scale

Treesearch

Maria Luisa Chas-Amil; Julia M. Touza; Jeffrey P. Prestemon; Colin J. McClean

2012-01-01

Development of efficient forest fire policies requires an understanding of the underlying reasons behind forest fire ignitions. Globally, there is a close relationship between forest fires and human activities, i.e., fires understood as human events due to negligence (e.g., agricultural burning escapes), and deliberate actions (e.g., pyromania, revenge, land use change...

Modeling impacts of fire severity on successional trajectories and future fire behavior in Alaskan boreal forests

Treesearch

Jill F. Johnstone; T. Scott Rupp; Mark Olson; David. Verbyla

2011-01-01

Much of the boreal forest in western North America and Alaska experiences frequent, stand-replacing wildfires. Secondary succession after fire initiates most forest stands and variations in fire characteristics can have strong effects on pathways of succession. Variations in surface fire severity that influence whether regenerating forests are dominated by coniferous...

Fire risk in east-side forests.

Treesearch

Valerie. Rapp

2002-01-01

Wildfire was a natural part of ecosystems in east-side Oregon and Washington before the 20th century. The fire regimes, or characteristic patterns of fire—how often, how hot, how big, what time of year—helped create and maintain various types of forests.Forests are dynamic, and fire interacts with other ecological processes. Fires, forests...

Contributions of microbial activity and ash deposition to post-fire nitrogen availability in a pine savanna

NASA Astrophysics Data System (ADS)

Ficken, Cari D.; Wright, Justin P.

2017-01-01

Many ecosystems experience drastic changes to soil nutrient availability associated with fire, but the magnitude and duration of these changes are highly variable among vegetation and fire types. In pyrogenic pine savannas across the southeastern United States, pulses of soil inorganic nitrogen (N) occur in tandem with ecosystem-scale nutrient losses from prescribed burns. Despite the importance of this management tool for restoring and maintaining fire-dependent plant communities, the contributions of different mechanisms underlying fire-associated changes to soil N availability remain unclear. Pulses of N availability following fire have been hypothesized to occur through (1) changes to microbial cycling rates and (2) direct ash deposition. Here, we document fire-associated changes to N availability across the growing season in a longleaf pine savanna in North Carolina. To differentiate between possible mechanisms driving soil N pulses, we measured net microbial cycling rates and changes to soil δ15N before and after a burn. Our findings refute both proposed mechanisms: we found no evidence for changes in microbial activity, and limited evidence that ash deposition could account for the increase in ammonium availability to more than 5-25 times background levels. Consequently, we propose a third mechanism to explain post-fire patterns of soil N availability, namely that (3) changes to plant sink strength may contribute to ephemeral increases in soil N availability, and encourage future studies to explicitly test this mechanism.

Landscape fragmentation, severe drought, and the new Amazon forest fire regime.

PubMed

Alencar, Ane A; Brando, Paulo M; Asner, Gregory P; Putz, Francis E

2015-09-01

Changes in weather and land use are transforming the spatial and temporal characteristics of fire regimes in Amazonia, with important effects on the functioning of dense (i.e., closed-canopy), open-canopy, and transitional forests across the Basin. To quantify, document, and describe the characteristics and recent changes in forest fire regimes, we sampled 6 million ha of these three representative forests of the eastern and southern edges of the Amazon using 24 years (1983-2007) of satellite-derived annual forest fire scar maps and 16 years of monthly hot pixel information (1992-2007). Our results reveal that changes in forest fire regime properties differentially affected these three forest types in terms of area burned and fire scar size, frequency, and seasonality. During the study period, forest fires burned 15% (0.3 million ha), 44% (1 million ha), and 46% (0.6 million ha) of dense, open, and transitional forests, respectively. Total forest area burned and fire scar size tended to increase over time (even in years of average rainfall in open canopy and transitional forests). In dense forests, most of the temporal variability in fire regime properties was linked to El Nino Southern Oscillation (ENSO)-related droughts. Compared with dense forests, transitional and open forests experienced fires twice as frequently, with at least 20% of these forests' areas burning two or more times during the 24-year study period. Open and transitional forests also experienced higher deforestation rates than dense forests. During drier years, the end of the dry season was delayed by about a month, which resulted in larger burn scars and increases in overall area burned later in the season. These observations suggest that climate-mediated forest flammability is enhanced by landscape fragmentation caused by deforestation, as observed for open and transitional forests in the Eastern portion of the Amazon Basin.

Creation and implementation of a certification system for insurability and fire risk classification for forest plantations

Treesearch

Veronica Loewe M.; Victor Vargas; Juan Miguel Ruiz; Andrea Alvarez C.; Felipe Lobo Q.

2015-01-01

Currently, the Chilean insurance market sells forest fire insurance policies and agricultural weather risk policies. However, access to forest fire insurance is difficult for small and medium enterprises (SMEs), with a significant proportion (close to 50%) of forest plantations being without coverage. Indeed, the insurance market that sells forest fire insurance...

77 FR 18997 - Rim Lakes Forest Restoration Project; Apache-Sitgreavese National Forest, Black Mesa Ranger...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-29

... uncharacteristicly high-severity wild fires, which can lead to loss of entire stands during one fire event. About 67..., fire, and wind. The purpose of the project is to restore forest health, move forests toward an uneven-aged forest structure with all age classes represented, and restore frequent, periodic surface fire as...

Future directions in EAB-affected forests

Treesearch

Deborah G. McCullough; Roy Van Driesche; Therese M. Poland

2015-01-01

The ability of natural enemies to slow emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), population growth in a given area will play a major role in determining whether many native ash species can persist as functional components of forest ecosystems. Population growth of EAB, like that of any other organism, is...

Beyond the Asian longhorned beetle and emerald ash borer

Treesearch

Robert K. Lawrence

2006-01-01

The Asian longhorned beetle (Anoplophora glabripennis) and emerald ash borer (Agrilus planipennis) are exotic forest insects that have had severe impacts on host tree species where they have become established in North America in recent years. Several other exotic forest arthropods have also appeared recently in North America, but...

Protection against fire in the mountainous forests of Greece case study: forest complex of W. Nestos

NASA Astrophysics Data System (ADS)

Drosos, Vasileios C.; Giannoulas, Vasileios J.; Stergiadou, Anastasia; Karagiannis, Evaggelos; Doukas, Aristotelis-Kosmas G.

2014-08-01

Forest fires are an ancient phenomenon. Appear, however, with devastating frequency and intensity over the last 30 years. In our country, the climatic conditions in combination with the intense relief, favor their rapid spread. Considering the fact that environmental conditions provided for decades even worse (increased temperature, drought and vegetation), then the problem of forest fires in our country, is expected to become more intense. The work focuses on the optimization model of the opening up of the forest mountain areas taking into account the prevention and suppression of forest fires. Research area is the mountain forest complex of W. Nestos of Drama Prefecture. The percentage of forest protection area is examined under the light whether the total hose length corresponds to the actual operational capacity to reach a fire source. For this reason are decided to present a three case study concerning area of the forest being protected by fire extinguishing vehicles. The first one corresponds to a fire suppression bandwidth (buffer zone) with a capacity radius of 150m uphill and 250m downhill from the origin point where the fire extinguishing vehicle stands. The second one corresponds to a fire suppression capacity of 200m uphill and 400m downhill and the third one corresponds to a fire suppression capacity of 300m uphill and 500m downhill. The most important forest technical infrastructures to prevent fire are roads network (opening up) for fire protection and buffer zones. Patrols of small and agile 4 × 4 appropriately equipped (pipe length of 500 meters and putting pressure on uphill to 300 meters) for the first attack of the fire in the summer months coupled with early warning of fire observatories adequately cover the forest protection of W. Nestos complex. But spatial distribution needed improvements to a road density of the optimum economic Dec, both forest protection and for better management (skidding) of woody capital.

Alternative characterization of forest fire regimes: incorporating spatial patterns

Treesearch

Brandon M. Collins; Jens T. Stevens; Jay D. Miller; Scott L. Stephens; Peter M. Brown; Malcolm P. North

2017-01-01

ContextThe proportion of fire area that experienced stand-replacing fire effects is an important attribute of individual fires and fire regimes in forests, and this metric has been used to group forest types into characteristic fire regimes. However, relying on proportion alone ignores important spatial characteristics...

Source water contributions and hydrologic responses to simulated emerald ash borer infestations in depressional black ash wetlands

Treesearch

Matthew J. Van Grinsven; Joseph P. Shannon; Joshua C. Davis; Nicholas W. Bolton; Joseph W. Wagenbrenner; Randall K. Kolka; Thomas Grant Pypker

2017-01-01

Forested wetlands dominated by black ash (Fraxinus nigra) are currently threatened by the rapid expansion of the exotic emerald ash borer (EAB) (Agrilus planipennis, Coleoptera: Buprestidae) in North America, and very little is known about the hydrology and ecology of black ash wetlands. The ecohydrological response of...

Physiological responses of emerald ash borer larvae to feeding on different ash species reveal putative resistance mechanisms and insect counter-adaptations

Treesearch

C.M. Rigsby; D.N. Showalter; D.A. Herms; J.L. Koch; P. Bonello; D. Cipollini

2015-01-01

Emerald ash borer, Agrilus planipennis Fairmaire, an Asian wood-boring beetle, has devastated ash (Fraxinus spp.) trees in North American forests and landscapes since its discovery there in 2002. In this study, we collected living larvae from EAB-resistant Manchurian ash (Fraxinus mandschurica), and susceptible...

The Role of Biocontrol of Emerald Ash Borer in Protecting Ash Regeneration after Invasion

USDA-ARS?s Scientific Manuscript database

Emerald ash borer (EAB) is an invasive Asian beetle that is destroying ash in forests over much of eastern North America because of the high susceptibility of our native ash and a lack of effective natural enemies. To increase mortality of EAB larvae and eggs, the USDA (FS, ARS and APHIS) is carryin...

A study of forest fire danger district division in Lushan Mountain based on RS and GIS

NASA Astrophysics Data System (ADS)

Xiao, Jinxiang; Huang, Shu-E.; Zhong, Anjian; Zhu, Biqin; Ye, Qing; Sun, Lijun

2009-09-01

The study selected 9 factors, average maximum temperature, average temperature, average precipitation, average the longest days of continuous drought and average wind speed during fire prevention period, vegetation type, altitude, slope and aspect as the index of forest fire danger district division, which has taken the features of Lushan Mountain's forest fire history into consideration, then assigned subjective weights to each factor according to their sensitivity to fire or their fire-inducing capability. By remote sensing and GIS, vegetation information layer were gotten from Landsat TM image and DEM with a scale of 1:50000 was abstracted from the digital scanned relief map. Topography info. (elevation, slope, aspect) layers could be gotten after that. A climate resource databank that contained the data from the stations of Lushan Mountain and other nearby 7 stations was built up and extrapolated through the way of grid extrapolation in order to make the distribution map of climate resource. Finally synthetical district division maps were made by weighing and integrating all the single factor special layers,and the study area were divided into three forest fire danger district, include special fire danger district, I-fire danger district and II-fire danger district. It could be used as a basis for developing a forest fire prevention system, preparing the annual investment plan, allocating reasonably the investment of fire prevention, developing the program of forest fire prevention and handle, setting up forest fire brigade, leaders' decisions on forest fire prevention work.

Analysis of zone of vulnurability and impact of forest fires in forest ecosystems in north algeria by susing remote sensing

NASA Astrophysics Data System (ADS)

Zegrar, Ahmed

2010-05-01

The Forest in steppe present ecological diversity, and seen climatic unfavourable conditions in zone and impact of forest fires; we notes deterioration of physical environment particularly, deterioration of natural forest. This deterioration of forests provokes an unbalance of environment witch provokes a process of deterioration advanced in the ultimate stadium is desertification. By elsewhere, where climatic conditions are favourable, the fire is an ecological and acted agent like integral part of evolution of the ecosystems, the specific regeneration of plants are influenced greatly by the regime of fire (season of fire, intensity, interval), witch leads to the recuperation of the vegetation of meadow- fire. In this survey we used the pictures ALSAT-1 for detection of zones with risk of forest fire and their impact on the naturals forests in region named TLEMCEN in the north west of Algeria. A thematic detailed analysis of forests well attended ecosystems some processing on the picture ALSAT-1, we allowed to identify and classifying the forests in there opinion components flowers. We identified ampleness of fire on this zone also. Some parameters as the slope, the proximity to the road and the forests formations were studied in the goal of determining the zones to risk of forest fire. A crossing of diaper of information in a GIS according to a very determined logic allowed classifying the zones in degree of risk of fire in semi arid zone witch forest zone not encouraging the regeneration but permitting the installation of cash of steppe which encourages the desertification.

Examining fire-induced forest changes using novel remote sensing technique: a case study in a mixed pine-oak forest

NASA Astrophysics Data System (ADS)

Meng, R.; Wu, J.; Zhao, F. R.; Cook, B.; Hanavan, R. P.; Serbin, S.

2017-12-01

Fire-induced forest changes has long been a central focus for forest ecology and global carbon cycling studies, and is becoming a pressing issue for global change biologists particularly with the projected increases in the frequency and intensity of fire with a warmer and drier climate. Compared with time-consuming and labor intensive field-based approaches, remote sensing offers a promising way to efficiently assess fire effects and monitor post-fire forest responses across a range of spatial and temporal scales. However, traditional remote sensing studies relying on simple optical spectral indices or coarse resolution imagery still face a number of technical challenges, including confusion or contamination of the signal by understory dynamics and mixed pixels with moderate to coarse resolution data (>= 30 m). As such, traditional remote sensing may not meet the increasing demand for more ecologically-meaningful monitoring and quantitation of fire-induced forest changes. Here we examined the use of novel remote sensing technique (i.e. airborne imaging spectroscopy and LiDAR measurement, very high spatial resolution (VHR) space-borne multi-spectral measurement, and high temporal-spatial resolution UAS-based (Unmanned Aerial System) imagery), in combination with field and phenocam measurements to map forest burn severity across spatial scales, quantify crown-scale post-fire forest recovery rate, and track fire-induced phenology changes in the burned areas. We focused on a mixed pine-oak forest undergoing multiple fire disturbances for the past several years in Long Island, NY as a case study. We demonstrate that (1) forest burn severity mapping from VHR remote sensing measurement can capture crown-scale heterogeneous fire patterns over large-scale; (2) the combination of VHR optical and structural measurements provides an efficient means to remotely sense species-level post-fire forest responses; (3) the UAS-based remote sensing enables monitoring of fire-induced forest phenology changes at unprecedented temporal and spatial resolutions. This work provides the methodological approach monitor fire-induced forest changes in a spatially explicit manner across scales, with important implications for fire-related forest management and for constraining/benchmarking process models.

Potential climate change impacts on fire intensity and key wildfire suppression thresholds in Canada

NASA Astrophysics Data System (ADS)

Wotton, B. M.; Flannigan, M. D.; Marshall, G. A.

2017-09-01

Much research has been carried out on the potential impacts of climate change on forest fire activity in the boreal forest. Indeed, there is a general consensus that, while change will vary regionally across the vast extent of the boreal, in general the fire environment will become more conducive to fire. Land management agencies must consider ways to adapt to these new conditions. This paper examines the impact of that changed fire environment on overall wildfire suppression capability. We use multiple General Circulation Models and carbon emission pathways to generate future fire environment scenarios for Canada’s forested region. We then use these scenarios with the Canadian Forest Fire Behaviour Prediction System and spatial coverages of the current forest fuel composition across the landscape to examine potential variation in key fire behaviour outputs that influence whether fire management resources can effectively suppress fire. Specifically, we evaluate how the potential for crown fire occurrence and active growth of fires changes with the changing climate. We also examine future fire behaviour through the lens of operational fire intensity thresholds used to guide decisions about resources effectiveness. Results indicate that the proportion of days in fire seasons with the potential for unmanageable fire will increase across Canada’s forest, more than doubling in some regions in northern and eastern boreal forest.

Microbial contents of soil from fire pits

NASA Astrophysics Data System (ADS)

Moon, K.; Esparza, V.; de Sandre, J.; Cheney, S.; Anderson, A.; White, M. A.

2006-12-01

Forest fires generate polycylic aromatic hydrocarbons (PAHs) that can lead to carcinogenic compounds, which are potential health risks. PAHs can be degraded to water and carbon dioxide by certain soil microbes. Thus, during participation in a NASA-funded summer research experience at Utah State University, our high school student team sampled soils from a month-old fire pit in which plant materials had been burnt. We detected in soil samples, from surface, 10 and 20 cm depths, microbes that would grow on a defined minimal medium source. Other microbes were cultured from the roots of plants that had established at the fire pit. A diversity of microbes was present in all samples based on visible differences in cell shape and color. It was surprising that the surface ash, although exposed to sunlight over the month interval, had culturable colonies. Many of these culturable bacteria were pigmented perhaps as a protection against UV radiation from the sun. We searched for genes in the microbes that encoded enzymes called dioxygenases that in other bacteria are involved in degradation of PAHs. This test involved using polymerase chain reactions to detect the genes. PCR products were found in two of the fifteen isolates tested although their sizes differed from the control gene product from a PAH-degrading mycobacterium isolate. These results suggest that the soils did contain microbes with the possible potential to alter the PAH compounds generated from vegetation fires. Our findings serve as a starting point for future studies looking at recovery and remediation of fired acreages.

Decreases in net primary production and net ecosystem production along a repeated-fires induced forest/grassland gradient

NASA Astrophysics Data System (ADS)

Cheng, C. H.; Huang, Y. H.; Chung-Yu, L.; Menyailo, O.

2016-12-01

Fire is one of the most important disturbances in ecosystems. Fire rapidly releases stored carbon into atmosphere and also plays critical roles on soil properties, light and moisture regimes, and plant structures and communities. With the interventions of climate change and human activities, fire regimes become more severe and frequent. In many parts of world, forest fire regimes can be further altered by grass invasion because the invasive grasses create a positive feedback cycle through their rapid recovery after fires and their high flammability during dry periods and allow forests to be burned repeatedly in a relatively short time. For such invasive grass-fire cycle, a great change of native vegetation community can occur. In this study, we examined a C4 invasive grass () fire-induced forest/grassland gradient to quantify the changes of net primary production (NPP) and net ecosystem production (NEP) from an unburned forest to repeated fire grassland. Our results demonstrated negative effects of repeated fires on NPP and NEP. Within 4 years of the onset of repeated fires on the unburned forest, NPP declined by 14%, mainly due to the reduction in aboveground NPP but offset by increase of belowground NPP. Subsequent fires cumulatively caused reductions in both aboveground and belowground NPP. A total of 40% reduction in the long-term repeated fire induced grassland was found. Soil respiration rate were not significantly different along the forest/grassland gradient. Thus, a great reduction in NEP were shown in grassland, which shifted from 4.6 Mg C ha-1 yr-1 in unburnt forest to -2.6 Mg C ha-1 yr-1. Such great losses are critical within the context of forest carbon cycling and long-term sustainability. Forest management practices that can effectively reduce the likelihood of repeated fires and consequent likelihood of establishment of the grass fire cycle are essential for protecting the forest.

Shifts in functional traits elevate risk of fire-driven tree dieback in tropical savanna and forest biomes.

PubMed

Pellegrini, Adam F A; Franco, Augusto C; Hoffmann, William A

2016-03-01

Numerous predictions indicate rising CO2 will accelerate the expansion of forests into savannas. Although encroaching forests can sequester carbon over the short term, increased fires and drought-fire interactions could offset carbon gains, which may be amplified by the shift toward forest plant communities more susceptible to fire-driven dieback. We quantify how bark thickness determines the ability of individual tree species to tolerate fire and subsequently determine the fire sensitivity of ecosystem carbon across 180 plots in savannas and forests throughout the 2.2-million km(2) Cerrado region in Brazil. We find that not accounting for variation in bark thickness across tree species underestimated carbon losses in forests by ~50%, totaling 0.22 PgC across the Cerrado region. The lower bark thicknesses of plant species in forests decreased fire tolerance to such an extent that a third of carbon gains during forest encroachment may be at risk of dieback if burned. These results illustrate that consideration of trait-based differences in fire tolerance is critical for determining the climate-carbon-fire feedback in tropical savanna and forest biomes. © 2015 John Wiley & Sons Ltd.

Defining fire environment zones in the boreal forests of northeastern China.

PubMed

Wu, Zhiwei; He, Hong S; Yang, Jian; Liang, Yu

2015-06-15

Fire activity in boreal forests will substantially increase with prolonged growing seasons under a warming climate. This trend poses challenges to managing fires in boreal forest landscapes. A fire environment zone map offers a basis for evaluating these fire-related problems and designing more effective fire management plans to improve the allocation of management resources across a landscape. Toward that goal, we identified three fire environment zones across boreal forest landscapes in northeastern China using analytical methods to identify spatial clustering of the environmental variables of climate, vegetation, topography, and human activity. The three fire environment zones were found to be in strong agreement with the spatial distributions of the historical fire data (occurrence, size, and frequency) for 1966-2005. This paper discusses how the resulting fire environment zone map can be used to guide forest fire management and fire regime prediction. Copyright © 2015 Elsevier B.V. All rights reserved.

Early forest dynamics in stand-replacing fire patches in the northern Sierra Nevada, California, USA

Treesearch

Brandon M. Collins; Gary B. Roller

2013-01-01

There is considerable concern over the occurrence of stand-replacing fire in forest types historically associated with low- to moderate-severity fire. The concern is largely over whether contemporary levels of stand-replacing fire are outside the historical range of variability, and what natural forest recovery is in these forest types following stand-replacing fire....

Indirect effects of emerald ash borer-induced ash mortality and canopy gap formation on epigaeic beetles.

PubMed

Gandhi, Kamal J K; Smith, Annemarie; Hartzler, Diane M; Herms, Daniel A

2014-06-01

Exotic herbivorous insects have drastically and irreversibly altered forest structure and composition of North American forests. For example, emerald ash borer (Agrilus planipennis Fairmaire) from Asia has caused wide-scale mortality of ash trees (Fraxinus spp.) in eastern United States and Canada. We studied the effects of forest changes resulting from emerald ash borer invasion on epigaeic or ground beetles (Coleoptera: Carabidae) along a gradient of ash dieback and gap sizes in southeastern Michigan. Ground beetles were sampled in hydric, mesic, and xeric habitats in which black (Fraxinus nigra Marshall), green (Fraxinus pennsylvanica Marshall), and white (Fraxinus americana L.) ash were the most common species, respectively. During 2006-2007, we trapped 2,545 adult ground beetles comprising 52 species. There was a negative correlation between percent ash tree mortality in 2006 and catches of all beetles. Catches of Agonum melanarium Dejean (in 2006) and Pterostichus mutus (Say) (in 2006-2007) were negatively correlated with tree mortality and gap size, respectively. However, catches of Pterostichus corvinus Dejean were positively correlated with gap size in 2006. As ash mortality and average gap size increased from 2006 to 2007, catches of all beetles as well as P. mutus and Pterostichus stygicus (Say) increased (1.3-3.9 times), while species diversity decreased, especially in mesic and xeric stands. Cluster analysis revealed that beetle assemblages in hydric and mesic stand diverged (25 and 40%, respectively) in their composition from 2006 to 2007, and that hydric stands had the most unique beetle assemblages. Overall, epigaeic beetle assemblages were altered in ash stands impacted by emerald ash borer; however, these impacts may dissipate as canopy gaps close.

ACUTE PULMONARY AND SYSTEMIC EFFECTS OF INHALED COAL FLY ASH IN RATS: COMPARISON TO AMBIENT ENVIRONMENTAL PARTICLES

EPA Science Inventory

Although primary particle emissions of ash from coal-fired power plants are well controlled, coal fly ash (CFA) can still remain a significant fraction of the overall particle exposure for some plant workers and highly impacted communities. The effect of CFA on pulmonary and syst...

Comparing soil and pond ash feedlot pen surfaces for environmental management

USDA-ARS?s Scientific Manuscript database

Removing manure and replacing soil to maintain pen surfaces is expensive. Pond ash (PA), a coal-fired electrical generation by-product, has good support qualities. A study was conducted comparing the performance of pond ash (PA) surfaced pens with soil surface (SS) pens. Four pens of an eight pen se...

Spatiotemporal patterns of fire-induced forest mortality in boreal regions and its potential drivers

NASA Astrophysics Data System (ADS)

Yang, J.; Tian, H.; Pan, S.; Hansen, M.; Wang, Y.

2017-12-01

Wildfire is the major natural disturbance in boreal forests, which have substantially affected various biological and biophysical processes. Although a few previous studies examined fire severity in boreal regions and reported a higher fire-induced forest mortality in boreal North America than in boreal Eurasia, it remains unclear how this mortality changes over time and how environmental factors affect the temporal dynamics of mortality at a large scale. By using a combination of multiple sources of satellite observations, we investigate the spatiotemporal patterns of fire-induced forest mortality in boreal regions, and examine the contributions of potential drivers. Our results show that forest composition is the key factor influencing the spatial variations of fire mortality across ecoregions. For the temporal variations, we find that the late-season burning was associated with higher fire intensity, which lead to greater forest mortality than the early-season burning. Forests burned in the warm and dry years had greater mortality than those burned in the cool and wet years. Our findings suggest that climate warming and drying not only stimulated boreal fire frequency, but also enhanced fire severity and forest mortality. Due to the significant effects of forest mortality on vegetation structure and ecosystem carbon dynamics, the spatiotemporal changes of fire-induced forest mortality should be explicitly considered to better understand fire impacts on regional and global climate change.

Effects of fire on small mammal communities in frequent-fire forests in California

USGS Publications Warehouse

Roberts, Susan L.; Kelt, Douglas A.; Van Wagtendonk, Jan W.; Miles, A. Keith; Meyer, Marc D.

2015-01-01

Fire is a natural, dynamic process that is integral to maintaining ecosystem function. The reintroduction of fire (e.g., prescribed fire, managed wildfire) is a critical management tool for protecting many frequent-fire forests against stand-replacing fires while restoring an essential ecological process. Understanding the effects of fire on forests and wildlife communities is important in natural resource planning efforts. Small mammals are key components of forest food webs and essential to ecosystem function. To investigate the relationship of fire to small mammal assemblages, we live trapped small mammals in 10 burned and 10 unburned forests over 2 years in the central Sierra Nevada, California. Small mammal abundance was higher in unburned forests, largely reflecting the greater proportion of closed-canopy species such as Glaucomys sabrinus in unburned forests. The most abundant species across the entire study area was the highly adaptable generalist species, Peromyscus maniculatus. Species diversity was similar between burned and unburned forests, but burned forests were characterized by greater habitat heterogeneity and higher small mammal species evenness. The use and reintroduction of fire to maintain a matrix of burn severities, including large patches of unburned refugia, creates a heterogeneous and resilient landscape that allows for fire-sensitive species to proliferate and, as such, may help maintain key ecological functions and diverse small mammal assemblages.

The influence of fire on lepidopteran abundance and community structure in forested habitats of eastern Texas

Treesearch

D. Craig Rudolph; Charles A. Ely

2000-01-01

Transect surveys were used to examine the influence of fire on lepidopteran communities (Papilionoidea and Hesperioidea) in forested habitats in eastern Texas. Lepidopteran abundance was greater in pine forests where prescribed fire maintained an open mid- and understory compared to forests where fire had less impact on forest structure. Ahundance of nectar sources...

The Zoning of Forest Fire Potential of Gulestan Province Forests Using Granular Computing and MODIS Images

NASA Astrophysics Data System (ADS)

Jalilzadeh Shadlouei, A.; Delavar, M. R.

2013-09-01

There are many vegetation in Iran. This is because of extent of Iran and its width. One of these vegetation is forest vegetation most prevalent in Northern provinces named Guilan, Mazandaran, Gulestan, Ardebil as well as East Azerbaijan. These forests are always threatened by natural forest fires so much so that there have been reports of tens of fires in recent years. Forest fires are one of the major environmental as well as economic, social and security concerns in the world causing much damages. According to climatology, forest fires are one of the important factors in the formation and dispersion of vegetation. Also, regarding the environment, forest fires cause the emission of considerable amounts of greenhouse gases, smoke and dust into the atmosphere which in turn causes the earth temperature to rise up and are unhealthy to humans, animals and vegetation. In agriculture droughts are the usual side effects of these fires. The causes of forest fires could be categorized as either Human or Natural Causes. Naturally, it is impossible to completely contain forest fires; however, areas with high potentials of fire could be designated and analysed to decrease the risk of fires. The zoning of forest fire potential is a multi-criteria problem always accompanied by inherent uncertainty like other multi-criteria problems. So far, various methods and algorithm for zoning hazardous areas via Remote Sensing (RS) and Geospatial Information System (GIS) have been offered. This paper aims at zoning forest fire potential of Gulestan Province of Iran forests utilizing Remote Sensing, Geospatial Information System, meteorological data, MODIS images and granular computing method. Granular computing is part of granular mathematical and one way of solving multi-criteria problems such forest fire potential zoning supervised by one expert or some experts , and it offers rules for classification with the least inconsistencies. On the basis of the experts' opinion, 6 determinative criterias contributing to forest fires have been designated as follows: vegetation (NDVI), slope, aspect, temperature, humidity and proximity to roadways. By applying these variables on several tentatively selected areas and formation information tables and producing granular decision tree and extraction of rules, the zoning rules (for the areas in question) were extracted. According to them the zoning of the entire area has been conducted. The zoned areas have been classified into 5 categories: high hazard, medium hazard (high), medium hazard (low), low hazard (high), low hazard (low). According to the map, the zoning of most of the areas fall into the low hazard (high) class while the least number of areas have been classified as low hazard (low). Comparing the forest fires in these regions in 2010 with the MODIS data base for forest fires, it is concluded that areas with high hazards of forest fire have been classified with a 64 percent precision. In other word 64 percent of pixels that are in high hazard classification are classified according to MODIS data base. Using this method we obtain a good range of Perception. Manager will reduce forest fire concern using precautionary proceeding on hazardous area.

Soot, organics and ultrafine ash from air- and oxy-fired coal ...

EPA Pesticide Factsheets

This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant stoichiometric ratios (SR = 1.2-1.4), but with the ability to maintain constant residence times (2.3 s). Experiments were conducted using a pulverized bituminous coal under air-combustion and three oxy-combustion inlet oxygen conditions (28, 32, and 36%). Size-classified fly ash samples were collected, and measurements focused on the composition of the total and ultrafine (<0.6 µm) fly ash produced, in particular the soot, elemental carbon (EC), and organic carbon (OC) fractions. Results indicate that although the total fly ash carbon, as measured by loss on ignition, was always acceptably low (<2%) with all three oxy-combustion conditions lower than air-combustion, the ultrafine fly ash for both air-fired and oxy-fired combustion conditions consists primarily of carbonaceous material (50-95%). Subsequent analyses of the carbonaceous component on particles <0.6 µm by a thermal optical method showed that large fractions (52-93%) consisted of OC rather than EC, as expected. This observation was supported by thermogravimetric analysis indicating that for the air, 28% oxy, and 32% oxy conditions, 14-71% of this material may be OC volatilizing between 100 and 550 °C with the remaining

Long-term effects of prescribed fire on mixed conifer forest structure in the Sierra Nevada, California

USGS Publications Warehouse

van Mantgem, Phillip J.; Stephenson, Nathan L.; Knapp, Eric; Keeley, Jon E.

2011-01-01

The capacity of prescribed fire to restore forest conditions is often judged by changes in forest structure within a few years following burning. However, prescribed fire might have longer-term effects on forest structure, potentially changing treatment assessments. We examined annual changes in forest structure in five 1 ha old-growth plots immediately before prescribed fire and up to eight years after fire at Sequoia National Park, California. Fire-induced declines in stem density (67% average decrease at eight years post-fire) were nonlinear, taking up to eight years to reach a presumed asymptote. Declines in live stem biomass were also nonlinear, but smaller in magnitude (32% average decrease at eight years post-fire) as most large trees survived the fires. The preferential survival of large trees following fire resulted in significant shifts in stem diameter distributions. Mortality rates remained significantly above background rates up to six years after the fires. Prescribed fire did not have a large influence on the representation of dominant species. Fire-caused mortality appeared to be spatially random, and therefore did not generally alter heterogeneous tree spatial patterns. Our results suggest that prescribed fire can bring about substantial changes to forest structure in old-growth mixed conifer forests in the Sierra Nevada, but that long-term observations are needed to fully describe some measures of fire effects.

Lethal trap trees: a potential option for emerald ash borer (Agrilus planipennis Fairmaire) management

Treesearch

Deborah G McCullough; Therese M. Poland; Phillip A. Lewis

2015-01-01

BACKGROUND: Economic and ecological impacts of ash (Fraxinus spp.) mortality resulting from emerald ash borer (EAB) (Agrilus planipennis Fairmaire) invasion are severe in forested, residential and urban areas. Management options include girdling ash trees to attract ovipositing adult beetles and then destroying infested trees...

Latent resilience in ponderosa pine forest: effects of resumed frequent fire.

PubMed

Larson, Andrew J; Belote, R Travis; Cansler, C Alina; Parks, Sean A; Dietz, Matthew S

2013-09-01

Ecological systems often exhibit resilient states that are maintained through negative feedbacks. In ponderosa pine forests, fire historically represented the negative feedback mechanism that maintained ecosystem resilience; fire exclusion reduced that resilience, predisposing the transition to an alternative ecosystem state upon reintroduction of fire. We evaluated the effects of reintroduced frequent wildfire in unlogged, fire-excluded, ponderosa pine forest in the Bob Marshall Wilderness, Montana, USA. Initial reintroduction of fire in 2003 reduced tree density and consumed surface fuels, but also stimulated establishment of a dense cohort of lodgepole pine, maintaining a trajectory toward an alternative state. Resumption of a frequent fire regime by a second fire in 2011 restored a low-density forest dominated by large-diameter ponderosa pine by eliminating many regenerating lodgepole pines and by continuing to remove surface fuels and small-diameter lodgepole pine and Douglas-fir that established during the fire suppression era. Our data demonstrate that some unlogged, fire-excluded, ponderosa pine forests possess latent resilience to reintroduced fire. A passive model of simply allowing lightning-ignited fires to burn appears to be a viable approach to restoration of such forests.

Disturbance severity and canopy position control the radial growth response of maple trees (Acer spp.) in forests of northwest Ohio impacted by emerald ash borer (Agrilus planipennis)

Treesearch

K.C. Costilow; Kathleen Knight; Charles Flower

2017-01-01

Key message. Radial growth of silver and red maples was investigated across three forests in northwest Ohio following the outbreak of the invasive emerald ash borer. The growth response of maples was driven by an advancement in canopy class and disturbance severity. Context. Forest disturbances resulting in species-specific diffuse mortality cause shifts in aboveground...

Avian community responses to post-fire forest structure: implications for fire management in mixed conifer forests

Treesearch

Angela White; Patricia Manley; Gina Tarbill; T. W. Richardson; R. E. Russell; H. D. Safford; S. Z. Dobrowski

2016-01-01

Fire is a natural process and the dominant disturbance shaping plant and animal communities in many coniferous forests of the western US. Given that fire size and severity are predicted to increase in the future, it has become increasingly important to understand how wildlife responds to fire and post-fire management. The Angora Fire...

Forest fires impact in semi arid lands in Algeria, analysis and followed of desertification by using remote sensing and GIS

NASA Astrophysics Data System (ADS)

Zegrar, Ahmed

The Forest in steppe present ecological diversity, and seen climatic unfavourable conditions in zone and impact of forest fires; we notes deterioration of physical environment particularly, deterioration of natural forest. This deterioration of forests provokes an unbalance of environment witch provokes a process of deterioration advanced in the ultimate stadium is desertification. By elsewhere, where climatic conditions are favourable, the fire is an ecological and acted agent like integral part of evolution of the ecosystems, the specific regeneration of plants are influenced greatly by the regime of fire (season of fire, intensity, interval), who leads to the recuperation of the vegetation of meadow- fire. In this survey we used the pictures ALSAT-1 for detection of zones with risk of forest fire and their impact on the naturals forests in region of Tlemcen. A thematic detailed analysis of forests well attended ecosystems some processing on the picture ALSAT-1, we allowed to identify and classifying the forests in there opinion components flowers. we identified ampleness of fire on this zone also. Some parameters as the slope, the proximity to the road and the forests formations were studied in the goal of determining the zones to risk of forest fire. A crossing of diaper of information in a SIG according to a very determined logic allowed to classify the zones in degree of risk of fire in a middle arid in a forest zone not encouraging the regeneration on the other hand permitting the installation of cash of steppe which encourages the desertification.

Aquatic ecotoxicity of ashes from Brazilian savanna wildfires.

PubMed

Brito, Darlan Q; Passos, Carlos José S; Muniz, Daphne H F; Oliveira-Filho, Eduardo C

2017-08-01

In a global scenario of climate change, several studies have predicted an increase in fires in different parts of the world. With the occurrence of rains following the fires in the Brazilian savanna (Cerrado biome), the compounds present in ashes may enter aquatic environments and cause adverse effects to these ecosystems. In this context, this study evaluated the potential toxicity of ashes from two areas of Cerrado and an area of pasture, through ecotoxicological bioassays and using three aquatic species from distinct trophic levels, which were exposed to different dilutions of ashes: the microcrustacean Ceriodaphnia dubia, the fish Danio rerio and the mollusc Biomphalaria glabrata. The ashes from the three sampled areas showed higher concentrations of some elements in relation to the soil samples (B, Ca, K, Mg, Mn, P, S, Si, Sr, Zn), but only a small quantity of these compounds was solubilised. Our data showed that all ash samples caused acute toxicity to C. dubia (48hs-LC 50  = 13.4 g L -1 ; 48hs-LC 50  = 6.33 g L -1 ; 48hs-LC 50  = 9.73 g L -1 respectively for transition area, pasture, typical cerrado areas), while in relation to D. rerio and B. glabrata, no acute toxicity was observed when they were exposed to ashes from native Cerrado vegetation and pasture areas. Ashes from a transition area showed toxicity for D. rerio (48hs-LC 50  = 25.0 g L -1 ); possibly, this was due to the combination of multiple preponderant inorganic elements of ashes with other organic compounds not analysed, such as polycyclic aromatic hydrocarbons (PAHs). In summary, these results suggest that wildfires may pose risks to zooplankton communities and emphasize the need for more studies to better understand the complexity of the ecological effects of fire on aquatic ecosystems.

Thirty-Two Years of Forest Service Research at the Southern Forest Fire Laboratory in Macon, GA

Treesearch

USDA Forest Service

1991-01-01

When completed in 1959, the Southern Forest Fire Laboratory was the world?s first devoted entirely to the study of forest fires, Since then the scientists at the Laboratory have: 1) performed basic and applied research on critical fire problems of national interest, 2) conducted special regional research on fire problems peculiar to the 13 Southern States, and 3)...

Modern fire regime resembles historical fire regime in a ponderosa pine forest on Native American land

Treesearch

Amanda B. Stan; Peter Z. Fule; Kathryn B. Ireland; Jamie S. Sanderlin

2014-01-01

Forests on tribal lands in the western United States have seen the return of low-intensity surface fires for several decades longer than forests on non-tribal lands. We examined the surface fire regime in a ponderosa pinedominated (Pinus ponderosa) forest on the Hualapai tribal lands in the south-western United States. Using fire-scarred trees, we inferred temporal (...

Simulations of Forest Fires by the Cellular Automata Model "ABBAMPAU"

NASA Astrophysics Data System (ADS)

di Gregorio, S.; Bendicenti, E.

2003-04-01

Forest fires represent a serious environmental problem, whose negative impact is becoming day by day more worrisome. Forest fires are very complex phenomena; that need an interdisciplinary approach. The adopted method to modelling involves the definition of local rules, from which the global behaviour of the system can emerge. The paradigm of Cellular Automata was applied and the model ABBAMPAU was projected to simulate the evolution of forest fires. Cellular Automata features (parallelism and a-centrism) seem to match the system "forest fire"; the parameters, describing globally a forest fire, i.e. propagation rate, flame length and direction, fireline intensity, fire duration time et c. are mainly depending on some local characteristics i.e. vegetation type (live and dead fuel), relative humidity, fuel moisture, heat, territory morphology (altitude, slope), et c.. The only global characteristic is given by wind velocity and direction, but wind velocity and direction is locally altered according to the morphology; therefore wind has also to be considered at local level. ABBAMPAU accounts for the following aspects of the phenomenon: effects of combustion in surface and crown fire inside the cell, crown fire triggering off; surface and crown fire spread, determination of the local wind rate and direction. A validation of ABBAMPAU was tested on a real case of forest fire, in the territory of Villaputzu, Sardinia island, August 22nd, 1998. First simulations account for the main characteristics of the phenomenon and agree with the observations. The results show that the model could be applied for the forest fire preventions, the productions of risk scenarios and the evaluation of the forest fire environmental impact.

Fire-mediated dieback and compositional cascade in an Amazonian forest.

PubMed

Barlow, Jos; Peres, Carlos A

2008-05-27

The only fully coupled land-atmosphere global climate model predicts a widespread dieback of Amazonian forest cover through reduced precipitation. Although these predictions are controversial, the structural and compositional resilience of Amazonian forests may also have been overestimated, as current vegetation models fail to consider the potential role of fire in the degradation of forest ecosystems. We examine forest structure and composition in the Arapiuns River basin in the central Brazilian Amazon, evaluating post-fire forest recovery and the consequences of recurrent fires for the patterns of dominance of tree species. We surveyed tree plots in unburned and once-burned forests examined 1, 3 and 9 years after an unprecedented fire event, in twice-burned forests examined 3 and 9 years after fire and in thrice-burned forests examined 5 years after the most recent fire event. The number of trees recorded in unburned primary forest control plots was stable over time. However, in both once- and twice-burned forest plots, there was a marked recruitment into the 10-20cm diameter at breast height tree size classes between 3 and 9 years post-fire. Considering tree assemblage composition 9 years after the first fire contact, we observed (i) a clear pattern of community turnover among small trees and the most abundant shrubs and saplings, and (ii) that species that were common in any of the four burn treatments (unburned, once-, twice- and thrice-burned) were often rare or entirely absent in other burn treatments. We conclude that episodic wildfires can lead to drastic changes in forest structure and composition, with cascading shifts in forest composition following each additional fire event. Finally, we use these results to evaluate the validity of the savannization paradigm.

Wildfire contribution to world-wide desertification.

NASA Astrophysics Data System (ADS)

Neary, D.; Wittenberg, L.; Bautista, S.; Ffolliott, P.

2009-04-01

Wildfire is a natural phenomenon that began with the development of terrestrial vegetation in a lightning-filled atmosphere. Sediments from the Carboniferous Period (307-359 million years before the present) contain evidence of charcoal from post-fire ash slurry flows. As human populations developed in the Pleistocene and Holocene epochs, mankind transformed fire into one of its oldest tools. Human and natural ignited fires from lightning altered and steered the trajectories of ecosystem development in most parts of the world. Humans are now the primary source of forest and grass fire ignitions throughout the world. As human populations have increased and industrialized in the past two centuries, fire ignitions and burned areas have increased due to both sheer numbers of people and anthropogenic changes in the global climate. Recent scientific findings have bolstered the hypothesis that climate change is resulting in fire seasons starting earlier, lasting longer, burning greater areas, and being more severe Computer models point to the Western U.S., Mediterranean nations and Brazil as "hot spots" that will get extremes at their worst. The climatic change to drier and warmer conditions has the potential to aggravate wildfire conditions, resulting in burning over longer seasons, larger areas of vegetation conflagration, and higher fire severities. Wildfire is now driving desertification in some of the forest lands in the western United States. The areas of wildfire in the Southwest USA have increased dramatically in the past two decades from <10,000 ha yr-1 in the early 20th Century to over 230,000 ha yr-1 in the first decade of the 21st Century. Individual wildfires are now larger and produce higher severity burns than in the past. A combination of natural drought, climate change, excessive fuel loads, and increased ignition sources have produced the perfect conditions for fire-induced desertification. Portugal suffered the worst and second worst wildfire seasons in a three-year period (2003 - 2005). In 2005, 338,262 ha of forest land burned. This was a 77% increase over the 10-year burn average of 189,500 ha. Desertification is about the loss of the land's proper hydrologic function, biological productivity, and other ecosystem services as a result of human activities and climate change. It affects one third of the earth's surface and over a billion people. In the past, desertification was considered a problem of only arid, semi-arid, and dry sub-humid areas. However, humid zones can undergo desertification with the wrong combination of human impacts. The Amazon region is an example of where forest harvesting, shifting cut and burn agriculture, and large-scale grazing are producing desertification of a tropical rain forest on a large scale. Some of the environmental consequences of wildfires are vegetation destruction, plant species and type shifts, exotic plant invasions, wildlife habitat destruction, soil erosion, floods, watershed function decline, water supply disruption, and air pollution. All of these are immediate impacts. Some impacts will persist beyond the careers and lifetimes of individuals. Small, isolated areas do not produce noticeable desertification. But, the cumulative effect of multiple, large area, and adjacent fires can be landscape-level desertification. This paper examines wildfire contributions to desertification in regions of the world that are prone to wildfire and climate change.

Use of unwounded ash trees for the detection of emerald ash borer adults: EAB landing behavior

Treesearch

Jordan M. Marshall; Melissa J. Porter; Andrew J. Storer

2011-01-01

Incorporation of multiple trapping techniques and sites within a survey program is essential to adequately identify the range of emerald ash borer (EAB) (Agrilus planipennis Fairmaire) infestation. Within natural forests, EAB lands on stick band traps wrapped around girdled ash trees at a rate similar to that on unwounded ash trees. The objective of...

The effect of wood ash fertilization on soil respiration and tree stand growth in boreal peatland forests

NASA Astrophysics Data System (ADS)

Liimatainen, Maarit; Maljanen, Marja; Hytönen, Jyrki

2017-04-01

Out of Finland's original 10 million hectares of peatlands over half has been drained for forestry. Natural peatlands act as a sink for carbon but when peatland is drained, increased oxygen concentration in the peat accelerates the aerobic decomposition of the old organic matter of the peat leading to carbon dioxide (CO2) emissions to atmosphere. Increasing use of bioenergy increases also the amount of ash produced as a byproduct in power plants. Wood ash contains all essential nutrients for trees to grow except nitrogen. Therefore, wood ash is ideal fertilizer for nitrogen rich peatland forests where lack of phosphorus or potassium may restrict tree growth. At the moment, wood ash is the only available PK-fertilizer for peatland forests in Finland and areas of peatland forests fertilized with ash are increasing annually. The effects of wood ash on vegetation, soil properties and tree growth are rather well known although most of the studies have been made using fine ash whereas nowadays mostly stabilized ash (e.g. granulated) is used. Transporting and spreading of stabilized ash is easier than that of dusty fine ash. Also, slower leaching rate of nutrients is environmentally beneficial and prolongs the fertilizer effect. The knowledge on the impact of granulated wood ash on greenhouse gas emissions is still very limited. The aim of this study was to examine the effects of granulated wood ash on CO2 emissions from peat and tree stand growth. Field measurements were done in two boreal peatland forests in 2011 and 2012. One of the sites is more nutrient rich with soil carbon to nitrogen ratio (C/N) of 18 whereas the other site is nutrient poor with C/N ratio of 82. Both sites were fertilized with granulated wood ash in 2003 (5000 kg ha-1). The effect of fertilization was followed with tree stand measurements conducted 0, 5 and 10 years after the fertilization. The CO2 emissions of the decomposing peat (heterotrophic respiration) were measured from study plots where vegetation and litter were removed to eliminate respiration by vegetation (autotrophic respiration). Roots were cut by installing aluminum tubes into the depth of 30 cm. Emissions were measured with chamber method using portable CO2 analyzer. Soil temperature was measured simultaneously with gas measurements manually from the depth of 5 cm as well as continuously with data loggers embedded into the peat. Annual soil respiration was modelled assuming that emissions change as a function of temperature. According to preliminary results, fertilization with granulated wood ash increased CO2 emissions of the peat significantly, especially in nutrient poor site. Ash fertilization increased also strongly the accumulation of carbon into the trees. Nonetheless, in both sites CO2emissions from decomposing peat where higher than carbon that was stored in biomass. This was the case especially in the nutrient poor site where trees are growing poorly and due to low peat nitrogen content the area is not considered suitable for ash fertilization. However, at the more fertile site both stand C sequestration and soil C efflux increased similarly.

Stand structure, fuelloads, and fire behavior in riparian and upland forests, Sierra Nevada Mountains, USA; a comparison of current and reconstructed conditions

Treesearch

Kip Van de Water; Malcolm North

2011-01-01

Fire plays an important role in shaping many Sierran coniferous forests, but longer fire return intervals and reductions in area burned have altered forest conditions. Productive, mesic riparian forests can accumulate high stem densities and fuel loads, making them susceptible to high-severity fire. Fuels treatments applied to upland forests, however, are...

The largest forest fires in Portugal: the constraints of burned area size on the comprehension of fire severity.

PubMed

Tedim, Fantina; Remelgado, Ruben; Martins, João; Carvalho, Salete

2015-01-01

Portugal is a European country with highest forest fires density and burned area. Since beginning of official forest fires database in 1980, an increase in number of fires and burned area as well as appearance of large and catastrophic fires have characterized fire activity in Portugal. In 1980s, the largest fires were just a little bit over 10,000 ha. However, in the beginning of 21st century several fires occurred with a burned area over 20,000 ha. Some of these events can be classified as mega-fires due to their ecological and socioeconomic severity. The present study aimed to discuss the characterization of large forest fires trend, in order to understand if the largest fires that occurred in Portugal were exceptional events or evidences of a new trend, and the constraints of fire size to characterize fire effects because, usually, it is assumed that larger the fire higher the damages. Using Portuguese forest fire database and satellite imagery, the present study showed that the largest fires could be seen at the same time as exceptional events and as evidence of a new fire regime. It highlighted the importance of size and patterns of unburned patches within fire perimeter as well as heterogeneity of fire ecological severity, usually not included in fire regime description, which are critical to fire management and research. The findings of this research can be used in forest risk reduction and suppression planning.

Distribution and Fate of Mercury in Pulverized Bituminous Coal-Fired Power Plants in Coal Energy-Dominant Huainan City, China.

PubMed

Chen, Bingyu; Liu, Guijian; Sun, Ruoyu

2016-05-01

A better understanding on the partitioning behavior of mercury (Hg) during coal combustion in large-scale coal-fired power plants is fundamental for drafting Hg-emission control regulations. Two large coal-fired utility boilers, equipped with electrostatic precipitators (ESPs) and a wet flue gas desulfurization (WFGD) system, respectively, in coal energy-dominant Huainan City, China, were selected to investigate the distribution and fate of Hg during coal combustion. In three sampling campaigns, we found that Hg in bottom ash was severely depleted with a relative enrichment (RE) index <7 %, whereas the RE index for fly ash (9-54%) was comparatively higher and variable. Extremely high Hg was concentrated in gypsum (≤4500 ng/g), which is produced in the WFGD system. Mass balance calculation shows that the shares of Hg in bottom ash, fly ash, WFGD products (gypsum, effluents, sludge), and stack emissions were <2, 17-32, 7-22, and 54-82%, respectively. The Hg-removal efficiencies of ESPs, WFGD, and ESPs + WFGD were 17-32, 10-29, and 36-46%, respectively. The Hg-emission factor of studied boilers was in a high range of 0.24-0.29 g Hg/t coal. We estimated that Hg emissions in all Huainan coal-fired power plants varied from 1.8 Mg in 2003 to 7.3 Mg in 2010.

Non-supervised method for early forest fire detection and rapid mapping

NASA Astrophysics Data System (ADS)

Artés, Tomás; Boca, Roberto; Liberta, Giorgio; San-Miguel, Jesús

2017-09-01

Natural hazards are a challenge for the society. Scientific community efforts have been severely increased assessing tasks about prevention and damage mitigation. The most important points to minimize natural hazard damages are monitoring and prevention. This work focuses particularly on forest fires. This phenomenon depends on small-scale factors and fire behavior is strongly related to the local weather. Forest fire spread forecast is a complex task because of the scale of the phenomena, the input data uncertainty and time constraints in forest fire monitoring. Forest fire simulators have been improved, including some calibration techniques avoiding data uncertainty and taking into account complex factors as the atmosphere. Such techniques increase dramatically the computational cost in a context where the available time to provide a forecast is a hard constraint. Furthermore, an early mapping of the fire becomes crucial to assess it. In this work, a non-supervised method for forest fire early detection and mapping is proposed. As main sources, the method uses daily thermal anomalies from MODIS and VIIRS combined with land cover map to identify and monitor forest fires with very few resources. This method relies on a clustering technique (DBSCAN algorithm) and on filtering thermal anomalies to detect the forest fires. In addition, a concave hull (alpha shape algorithm) is applied to obtain rapid mapping of the fire area (very coarse accuracy mapping). Therefore, the method leads to a potential use for high-resolution forest fire rapid mapping based on satellite imagery using the extent of each early fire detection. It shows the way to an automatic rapid mapping of the fire at high resolution processing as few data as possible.

Fire regime in a Mexican forest under indigenous resource management.

PubMed

Fulé, Peter Z; Ramos-Gómez, Mauro; Cortés-Montaño, Citlali; Miller, Andrew M

2011-04-01

The Rarámuri (Tarahumara) people live in the mountains and canyons of the Sierra Madre Occidental of Chihuahua, Mexico. They base their subsistence on multiple-use strategies of their natural resources, including agriculture, pastoralism, and harvesting of native plants and wildlife. Pino Gordo is a Rarámuri settlement in a remote location where the forest has not been commercially logged. We reconstructed the forest fire regime from fire-scarred trees, measured the structure of the never-logged forest, and interviewed community members about fire use. Fire occurrence was consistent throughout the 19th and 20th centuries up to our fire scar collection in 2004. This is the least interrupted surface-fire regime reported to date in North America. Studies from other relict sites such as nature reserves in Mexico or the USA have all shown some recent alterations associated with industrialized society. At Pino Gordo, fires recurred frequently at the three study sites, with a composite mean fire interval of 1.9 years (all fires) to 7.6 years (fires scarring 25% or more of samples). Per-sample fire intervals averaged 10-14 years at the three sites. Approximately two-thirds of fires burned in the season of cambial dormancy, probably during the pre-monsoonal drought. Forests were dominated by pines and contained many large living trees and snags, in contrast to two nearby similar forests that have been logged. Community residents reported using fire for many purposes, consistent with previous literature on fire use by indigenous people. Pino Gordo is a valuable example of a continuing frequent-fire regime in a never-harvested forest. The Rarámuri people have actively conserved this forest through their traditional livelihood and management techniques, as opposed to logging the forest, and have also facilitated the fire regime by burning. The data contribute to a better understanding of the interactions of humans who live in pine forests and the fire regimes of these ecosystems, a topic that has been controversial and difficult to assess from historical or paleoecological evidence.

Disturbance and productivity interactions mediate stability of forest composition and structure.

PubMed

O'Connor, Christopher D; Falk, Donald A; Lynch, Ann M; Swetnam, Thomas W; Wilcox, Craig P

2017-04-01

Fire is returning to many conifer-dominated forests where species composition and structure have been altered by fire exclusion. Ecological effects of these fires are influenced strongly by the degree of forest change during the fire-free period. Response of fire-adapted species assemblages to extended fire-free intervals is highly variable, even in communities with similar historical fire regimes. This variability in plant community response to fire exclusion is not well understood; however, ecological mechanisms such as individual species' adaptations to disturbance or competition and underlying site characteristics that facilitate or impede establishment and growth have been proposed as potential drivers of assemblage response. We used spatially explicit dendrochronological reconstruction of tree population dynamics and fire regimes to examine the influence of historical disturbance frequency (a proxy for adaptation to disturbance or competition), and potential site productivity (a proxy for underlying site characteristics) on the stability of forest composition and structure along a continuous ecological gradient of pine, dry mixed-conifer, mesic mixed-conifer, and spruce-fir forests following fire exclusion. While average structural density increased in all forests, species composition was relatively stable in the lowest productivity pine-dominated and highest productivity spruce-fir-dominated sites immediately following fire exclusion and for the next 100 years, suggesting site productivity as a primary control on species composition and structure in forests with very different historical fire regimes. Species composition was least stable on intermediate productivity sites dominated by mixed-conifer forests, shifting from primarily fire-adapted species to competition-adapted, fire-sensitive species within 20 years of fire exclusion. Rapid changes to species composition and stand densities have been interpreted by some as evidence of high-severity fire. We demonstrate that the very different ecological process of fire exclusion can produce similar changes by shifting selective pressures from disturbance-mediated to productivity-mediated controls. Restoring disturbance-adapted species composition and structure to intermediate productivity forests may help to buffer them against projected increasing temperatures, lengthening fire seasons, and more frequent and prolonged moisture stress. Fewer management options are available to promote adaptation in forest assemblages historically constrained by underlying site productivity. © 2016 by the Ecological Society of America.

Variation in fire regimes of the Rocky Mountains: Implications for avian communities and fire management

USGS Publications Warehouse

Saab, Victoria A.; Powell, Hugo D.W.; Kotliar, Natasha B.; Newlon, Karen R.; Saab, Victoria A.; Powell, Hugo D.W.

2005-01-01

Information about avian responses to fire in the U.S. Rocky Mountains is based solely on studies of crown fires. However, fire management in this region is based primarily on studies of low-elevation ponderosa pine (Pinus ponderosa) forests maintained largely by frequent understory fires. In contrast to both of these trends, most Rocky Mountain forests are subject to mixed severity fire regimes. As a result, our knowledge of bird responses to fire in the region is incomplete and skewed toward ponderosa pine forests. Research in recent large wildfires across the Rocky Mountains indicates that large burns support diverse avifauna. In the absence of controlled studies of bird responses to fire, we compared reproductive success for six cavity-nesting species using results from studies in burned and unburned habitats. Birds in ponderosa pine forests burned by stand-replacement fire tended to have higher nest success than individuals of the same species in unburned habitats, but unburned areas are needed to serve species dependent upon live woody vegetation, especially foliage gleaners. Over the last century, fire suppression, livestock grazing, and logging altered the structure and composition of many low-elevation forests, leading to larger and more severe burns. In higher elevation forests, changes have been less marked. Traditional low-severity prescribed fire is not likely to replicate historical conditions in these mixed or high-severity fire regimes, which include many mixed coniferous forests and all lodgepole pine (Pinus contorta) and spruce-fi r (Picea-Abies) forests. We suggest four research priorities: (1) the effects of fire severity and patch size on species’ responses to fire, (2) the possibility that postfire forests are ephemeral sources for some bird species, (3) the effect of salvage logging prescriptions on bird communities, and (4) experiments that illustrate bird responses to prescribed fire and other forest restoration methods. This research is urgent if we are to develop fire management strategies that reduce fire risk and maintain habitat for avifauna and other wildlife of the Rocky Mountains.

Variation in fire regimes of the rocky mountains: Implications for avian communities and fire management

USGS Publications Warehouse

Saab, V.A.; Powell, Hugo D.W.; Kotliar, N.B.; Newlon, K.R.

2005-01-01

Information about avian responses to fire in the U.S. Rocky Mountains is based solely on studies of crown fires. However, fire management in this region is based primarily on studies of low-elevation ponderosa pine (Pinus ponderosa) forests maintained largely by frequent understory fires. In contrast to both of these trends, most Rocky Mountain forests are subject to mixed severity fire regimes. As a result, our knowledge of bird responses to fire in the region is incomplete and skewed toward ponderosa pine forests. Research in recent large wildfires across the Rocky Mountains indicates that large burns support diverse avifauna. In the absence of controlled studies of bird responses to fire, we compared reproductive success for six cavity-nesting species using results from studies in burned and unburned habitats. Birds in ponderosa pine forests burned by stand-replacement fire tended to have higher nest success than individuals of the same species in unburned habitats, but unburned areas are needed to serve species dependent upon live woody vegetation, especially foliage gleaners. Over the last century, fire suppression, livestock grazing, and logging altered the structure and composition of many low-elevation forests, leading to larger and more severe burns. In higher elevation forests, changes have been less marked. Traditional low-severity prescribed fire is not likely to replicate historical conditions in these mixed or high-severity fire regimes, which include many mixed coniferous forests and all lodgepole pine (Pinus contorta) and spruce-fir (Picea-Abies) forests. We suggest four research priorities: (1) the effects of fire severity and patch size on species' responses to fire, (2) the possibility that postfire forests are ephemeral sources for some bird species, (3) the effect of salvage logging prescriptions on bird communities, and (4) experiments that illustrate bird responses to prescribed fire and other forest restoration methods. This research is urgent if we are to develop fire management strategies that reduce fire risk and maintain habitat for avifauna and other wildlife of the Rocky Mountains.

The influence of weather and fuel type on the fuel composition of the area burned by forest fires in Ontario, 1996-2006.

PubMed

Podur, Justin J; Martell, David L

2009-07-01

Forest fires are influenced by weather, fuels, and topography, but the relative influence of these factors may vary in different forest types. Compositional analysis can be used to assess the relative importance of fuels and weather in the boreal forest. Do forest or wild land fires burn more flammable fuels preferentially or, because most large fires burn in extreme weather conditions, do fires burn fuels in the proportions they are available despite differences in flammability? In the Canadian boreal forest, aspen (Populus tremuloides) has been found to burn in less than the proportion in which it is available. We used the province of Ontario's Provincial Fuels Database and fire records provided by the Ontario Ministry of Natural Resources to compare the fuel composition of area burned by 594 large (>40 ha) fires that occurred in Ontario's boreal forest region, a study area some 430,000 km2 in size, between 1996 and 2006 with the fuel composition of the neighborhoods around the fires. We found that, over the range of fire weather conditions in which large fires burned and in a study area with 8% aspen, fires burn fuels in the proportions that they are available, results which are consistent with the dominance of weather in controlling large fires.

Mathematical modeling of forest fire initiation in three dimensional setting

Treesearch

Valeriy Perminov

2007-01-01

In this study, the assignment and theoretical investigations of the problems of forest fire initiation were carried out, including development of a mathematical model for description of heat and mass transfer processes in overterrestrial layer of atmosphere at crown forest fire initiation, taking into account their mutual influence. Mathematical model of forest fire...

Measurements of forest fire danger

Treesearch

Leo Shames

1938-01-01

Although the annual destruction of life and property attributable to forest fires is enormous, scientific methods of forest fire control in the United States are of comparatively recent origin. In one important phase of control, that of determining how large a network of observers is necessary for the purpose of discovering forest fires in their infancy, accurate means...

Fire regimes and approaches for determining fire history

Treesearch

James K. Agee

1996-01-01

Fire has been an important evolutionary influence in forests, affecting species composition, structure, and functional aspects of forest biology. Restoration of wildland forests of the future will depend in part on restoring fire to an appropriate role in forest ecosystems. This may include the "range of natural variability" or other concepts associated with...

Strategy for increasing the participation of masyarakat peduli api in forest fire control

NASA Astrophysics Data System (ADS)

Ni’mah, N. L. K.; Herdiansyah, H.; Soesilo, T. E. B.; Mutia, E. F.

2018-03-01

Forest fires have negative impact on ecology, health, and damage economic activities. One of conservation areas facing the threat of forest fire is Gunung Ciremai National Park. This research aims to formulate a strategy to increase the participation of Masyarakat Peduli Api in the effort of forest fire control. This research use quantitative method with SWOT analysis. Expert consisting of representatives from the national park, Ministry of Environment and Forestry, and BPBD Kuningan Regency. An alternative strategy based on SWOT analysis is in quadrant 1 with coordinate point (0,39; 1,23). The position shows that sustainability of national park management through forest fire control can be done with an aggressive strategy. That is maximizing the strength that is owned with its potential as an ecotourism area to increase community motivation to engage in forest fire control activities. Provision of tourism management licenses will create employment opportunities and increase income for the community so it is expected to increase community participation to prevent the occurrence of forest fires rather than forest fire prevention.

Effects of prescribed fire on wintering, bark-foraging birds in northern Arizona

Treesearch

Theresa L. Pope

2006-01-01

Forest management practices of the past century have led to an increase in unnatural and destructive crown fires in ponderosa pine (Pinus ponderosa) forests of the southwest. To combat large fires, forest managers are attempting to simulate past fire regimes of low-intensity surface fires using prescribed fire. While there have been many studies...

Disturbance and productivity interactions mediate stability of forest composition and structure

Treesearch

Christopher D. O' Connor; Donald A. Falk; Ann M. Lynch; Thomas W. Swetnam; Craig P. Wilcox

2017-01-01

Fire is returning to many conifer-dominated forests where species composition and structure have been altered by fire exclusion. Ecological effects of these fires are influenced strongly by the degree of forest change during the fire-free period. Response of fire-adapted species assemblages to extended fire-free intervals is highly variable, even in communities with...

Improvement of Forest Fire Detection Algorithm Using Brightness Temperature Lapse Rate Correction in HIMAWARI-8 IR Channels: Application to the 6 may 2017 Samcheok City, Korea

NASA Astrophysics Data System (ADS)

Park, S. H.; Park, W.; Jung, H. S.

2018-04-01

Forest fires are a major natural disaster that destroys a forest area and a natural environment. In order to minimize the damage caused by the forest fire, it is necessary to know the location and the time of day and continuous monitoring is required until fire is fully put out. We have tried to improve the forest fire detection algorithm by using a method to reduce the variability of surrounding pixels. We focused that forest areas of East Asia, part of the Himawari-8 AHI coverage, are mostly located in mountainous areas. The proposed method was applied to the forest fire detection in Samcheok city, Korea on May 6 to 10, 2017.

Removal of introduced inorganic content from chipped forest residues via air classification

DOE PAGES

Lacey, Jeffrey A.; Aston, John E.; Westover, Tyler L.; ...

2015-08-04

Inorganic content in biomass decreases the efficiency of conversion processes, especially thermochemical conversions. The combined concentrations of specific ash forming elements are the primary attributes that cause pine residues to be considered a degraded energy conversion feedstock, as compared to clean pine. Air classification is a potentially effective and economical tool to isolate high inorganic content biomass fractions away from primary feedstock sources to reduce their ash content. In this work, loblolly pine forest residues were air classified into 10 fractions whose ash content and composition were measured. Ash concentrations were highest in the lightest fractions (5.8–8.5 wt%), and inmore » a heavy fraction of the fines (8.9–15.1 wt%). The removal of fractions with high inorganic content resulted in a substantial reduction in the ash content of the remaining biomass in forest thinnings (1.69–1.07 wt%) and logging residues (1.09–0.68 wt%). These high inorganic content fractions from both forest residue types represented less than 7.0 wt% of the total biomass, yet they contained greater than 40% of the ash content by mass. Elemental analysis of the air classified fractions revealed the lightest fractions were comprised of high concentrations of soil elements (silicon, aluminum, iron, sodium, and titanium). However, the elements of biological origin including calcium, potassium, magnesium, sulfur, manganese, and phosphorous were evenly distributed throughout all air classified fractions, making them more difficult to isolate into fractions with high mineral concentrations. Under the conditions reported in this study, an economic analysis revealed air classification could be used for ash removal for as little as $2.23 per ton of product biomass. As a result, this study suggests air classification is a potentially attractive technology for the removal of introduced soil minerals from pine forest residues.« less

Using Airborne LIDAR Data for Assessment of Forest Fire Fuel Load Potential

NASA Astrophysics Data System (ADS)

İnan, M.; Bilici, E.; Akay, A. E.

2017-11-01

Forest fire incidences are one of the most detrimental disasters that may cause long terms effects on forest ecosystems in many parts of the world. In order to minimize environmental damages of fires on forest ecosystems, the forested areas with high fire risk should be determined so that necessary precaution measurements can be implemented in those areas. Assessment of forest fire fuel load can be used to estimate forest fire risk. In order to estimate fuel load capacity, forestry parameters such as number of trees, tree height, tree diameter, crown diameter, and tree volume should be accurately measured. In recent years, with the advancements in remote sensing technology, it is possible to use airborne LIDAR for data estimation of forestry parameters. In this study, the capabilities of using LIDAR based point cloud data for assessment of the forest fuel load potential was investigated. The research area was chosen in the Istanbul Bentler series of Bahceköy Forest Enterprise Directorate that composed of mixed deciduous forest structure.

Temporal scaling behavior of forest and urban fires

NASA Astrophysics Data System (ADS)

Wang, J.; Song, W.; Zheng, H.; Telesca, L.

2009-04-01

It has been found that many natural systems are characterized by scaling behavior. In such systems natural factors dominate the event dynamics. Forest fires in different countries have been found to exhibit frequency-size power law over many orders of magnitude and with similar value of parameters. But in countries with high population density such as China and Japan, more than 95% of the forest fire disasters are caused by human activities. Furthermore, with the development of society, the wildland-urban interface (WUI) area is becoming more and more populated, and the forest fire is much connected with urban fire. Therefore exploring the scaling behavior of fires dominated by human-related factors is very challenging. The present paper explores the temporal scaling behavior of forest fires and urban fires in Japan with mathematical methods. Two factors, Allan factor (AF) and Fano factor (FF) are used to investigate time-scaling of fire systems. It is found that the FF for both forest fires and urban fires increases linearly in log-log scales, and this indicates that it behaves as a power-law for all the investigated timescales. From the AF plot a 7 days cycle is found, which indicates a weekly cycle. This may be caused by human activities which has a weekly periodicity because on weekends people usually have more outdoor activities, which may cause more hidden trouble of fire disasters. Our findings point out that although the human factors are the main cause, both the forest fires and urban fires exhibit time-scaling behavior. At the same time, the scaling exponents for urban fires are larger than forest fires, signifying a more intense clustering. The reason may be that fires are affected not only by weather condition, but also by human activities, which play a more important role for urban fires than forest fires and have a power law distribution and scaling behavior. Then some work is done to the relative humidity. Similar distribution law characterizes the relative humidity. The AF plot and FF plot of relative humidity validate the existence of a strong link between weather and fires, and it is very likely that the daily humidity cycle determines the daily fire periodicity.

Severe fire weather and intensive forest management increase fire severity in a multi-ownership landscape.

PubMed

Zald, Harold S J; Dunn, Christopher J

2018-04-26

Many studies have examined how fuels, topography, climate, and fire weather influence fire severity. Less is known about how different forest management practices influence fire severity in multi-owner landscapes, despite costly and controversial suppression of wildfires that do not acknowledge ownership boundaries. In 2013, the Douglas Complex burned over 19,000 ha of Oregon & California Railroad (O&C) lands in Southwestern Oregon, USA. O&C lands are composed of a checkerboard of private industrial and federal forestland (Bureau of Land Management, BLM) with contrasting management objectives, providing a unique experimental landscape to understand how different management practices influence wildfire severity. Leveraging Landsat based estimates of fire severity (Relative differenced Normalized Burn Ratio, RdNBR) and geospatial data on fire progression, weather, topography, pre-fire forest conditions, and land ownership, we asked (1) what is the relative importance of different variables driving fire severity, and (2) is intensive plantation forestry associated with higher fire severity? Using Random Forest ensemble machine learning, we found daily fire weather was the most important predictor of fire severity, followed by stand age and ownership, followed by topographic features. Estimates of pre-fire forest biomass were not an important predictor of fire severity. Adjusting for all other predictor variables in a general least squares model incorporating spatial autocorrelation, mean predicted RdNBR was higher on private industrial forests (RdNBR 521.85 ± 18.67 [mean ± SE]) vs. BLM forests (398.87 ± 18.23) with a much greater proportion of older forests. Our findings suggest intensive plantation forestry characterized by young forests and spatially homogenized fuels, rather than pre-fire biomass, were significant drivers of wildfire severity. This has implications for perceptions of wildfire risk, shared fire management responsibilities, and developing fire resilience for multiple objectives in multi-owner landscapes. © 2018 by the Ecological Society of America.

Impacts of the Canadian forest fires on atmospheric mercury and carbonaceous particles in Northern New York.

PubMed

Wang, Yungang; Huang, Jiaoyan; Zananski, Tiffany J; Hopke, Philip K; Holsen, Thomas M

2010-11-15

The impact of Canadian forest fires in Quebec on May 31, 2010 on PM(2.5), carbonaceous species, and atmospheric mercury species was observed at three rural sites in northern New York. The results were compared with previous studies during a 2002 Quebec forest fire episode. MODIS satellite images showed transport of forest fire smoke from southern Quebec, Canada to northern New York on May 31, 2010. Back-trajectories were consistent with this regional transport. During the forest fire event, as much as an 18-fold increase in PM(2.5) concentration was observed. The concentrations of episode-related OC, EC, BC, UVBC, and their difference (Delta-C), reactive gaseous mercury (RGM), and particle-bound mercury (PBM) were also significantly higher than those under normal conditions, suggesting a high impact of Canadian forest fire emissions on air quality in northern New York. PBM, RGM, and Delta-C are all emitted from forest fires. The correlation coefficient between Delta-C and other carbonaceous species may serve as an indicator of forest fire smoke. Given the marked changes in PBM, it may serve as a more useful tracer of forest fires over distances of several hundred kilometers relative to GEM. However, the Delta-C concentration changes are more readily measured.

Web-GIS platform for forest fire danger prediction in Ukraine: prospects of RS technologies

NASA Astrophysics Data System (ADS)

Baranovskiy, N. V.; Zharikova, M. V.

2016-10-01

There are many different statistical and empirical methods of forest fire danger use at present time. All systems have not physical basis. Last decade deterministic-probabilistic method is rapidly developed in Tomsk Polytechnic University. Forest sites classification is one way to estimate forest fire danger. We used this method in present work. Forest fire danger estimation depends on forest vegetation condition, forest fire retrospective, precipitation and air temperature. In fact, we use modified Nesterov Criterion. Lightning activity is under consideration as a high temperature source in present work. We use Web-GIS platform for program realization of this method. The program realization of the fire danger assessment system is the Web-oriented geoinformation system developed by the Django platform in the programming language Python. The GeoDjango framework was used for realization of cartographic functions. We suggest using of Terra/Aqua MODIS products for hot spot monitoring. Typical territory for forest fire danger estimation is Proletarskoe forestry of Kherson region (Ukraine).

Forest fires in Missouri.

Treesearch

Donald A. Haines; William A. Main; John S. Crosby

1973-01-01

Describes factors that contribute to forest fires on two of the State of Missouri's Protection Districts and the Clark National Forest. Includes an analysis of fire cause, annual distribution, weather, and activity by day of week; also discusses multiple-fire day.

Interactive effects of historical logging and fire exclusion on ponderosa pine forest structure in the northern Rockies.

PubMed

Naficy, Cameron; Sala, Anna; Keeling, Eric G; Graham, Jon; DeLuca, Thomas H

2010-10-01

Increased forest density resulting from decades of fire exclusion is often perceived as the leading cause of historically aberrant, severe, contemporary wildfires and insect outbreaks documented in some fire-prone forests of the western United States. Based on this notion, current U.S. forest policy directs managers to reduce stand density and restore historical conditions in fire-excluded forests to help minimize high-severity disturbances. Historical logging, however, has also caused widespread change in forest vegetation conditions, but its long-term effects on vegetation structure and composition have never been adequately quantified. We document that fire-excluded ponderosa pine forests of the northern Rocky Mountains logged prior to 1960 have much higher average stand density, greater homogeneity of stand structure, more standing dead trees and increased abundance of fire-intolerant trees than paired fire-excluded, unlogged counterparts. Notably, the magnitude of the interactive effect of fire exclusion and historical logging substantially exceeds the effects of fire exclusion alone. These differences suggest that historically logged sites are more prone to severe wildfires and insect outbreaks than unlogged, fire-excluded forests and should be considered a high priority for fuels reduction treatments. Furthermore, we propose that ponderosa pine forests with these distinct management histories likely require distinct restoration approaches. We also highlight potential long-term risks of mechanical stand manipulation in unlogged forests and emphasize the need for a long-term view of fuels management.

Development and analysis of a 12-year daily 1-km forest fire dataset across North America from NOAA/AVHRR

Treesearch

Ruiliang Pu; Zhanqing Li; Peng Gong; Ivan Csiszar; Robert Fraser; Wei-Min Hao; Shobha Kondragunta; Fuzhong Weng

2007-01-01

Fires in boreal and temperate forests play a significant role in the global carbon cycle. While forest fires in North America (NA) have been surveyed extensively by U.S. and Canadian forest services, most fire records are limited to seasonal statistics without information on temporal evolution and spatial expansion. Such dynamic information is crucial for modeling fire...

Fire History of a Forest, Savanna, and Fen Mosaic at White Ranch State Forest

Treesearch

Daniel C. Dey; Ricahrd P. Guyette; Michael C. Stambaugh

2004-01-01

We present the fire history of a 1-km2 area that is a mosaic of oak forest, savanna, and fen on the White Ranch State Forest, Howell County, Missouri. We dated 135 fire scars on 35 cross-sections of post oak ( Quercus stellata) trees and constructed a fire chronology dating from 1705 to 1997. Mean fire return intervals by periods were 3.7 years (...

Design and realization of disaster assessment algorithm after forest fire

NASA Astrophysics Data System (ADS)

Xu, Aijun; Wang, Danfeng; Tang, Lihua

2008-10-01

Based on GIS technology, this paper mainly focuses on the application of disaster assessment algorithm after forest fire and studies on the design and realization of disaster assessment based on GIS. After forest fire through the analysis and processing of multi-sources and heterogeneous data, this paper integrates the foundation that the domestic and foreign scholars laid of the research on assessment for forest fire loss with the related knowledge of assessment, accounting and forest resources appraisal so as to study and approach the theory framework and assessment index of the research on assessment for forest fire loss. The technologies of extracting boundary, overlay analysis, and division processing of multi-sources spatial data are available to realize the application of the investigation method of the burnt forest area and the computation of the fire area. The assessment provides evidence for fire cleaning in burnt areas and new policy making on restoration in terms of the direct and the indirect economic loss and ecological and environmental damage caused by forest fire under the condition of different fire danger classes and different amounts of forest accumulation, thus makes forest resources protection operated in a faster, more efficient and more economical way. Finally, this paper takes Lin'an city of Zhejiang province as a test area to confirm the method mentioned in the paper in terms of key technologies.

A one year post-fire biogeochemical cycling record of a sandstone mountain fynbos ecosystem, South Africa

NASA Astrophysics Data System (ADS)

Bergh, E.; Compton, J. S.

2012-04-01

The Cape Floristic Region (CFR) in southwestern South Africa is a Mediterranean-type ecosystem dominated by highly diverse and endemic fynbos vegetation. In this study, the chemistry of rainwater (total wet and dry deposition), stream water and soil saturated paste extracts of the sandstone fynbos biome of the Kogelberg Biosphere Reserve reveals how the cycling of Cl, Na, SO4,Mg, Ca and K varied over a one year period following a major fire event. Fire is a critical component of fynbos ecology, but the fynbos ecosystem is under threat as the fire return frequency increases as a result of human activities. The underlying bedrock geology of the sandstone fynbos biome is dominated by quartz-rich (>97 wt% SiO2) sandstone providing few nutrients to the overlying thin (2 to 20 cm), acidic soils. Additional sources of nutrients to the ecosystem are derived from windblown marine and dust (consisting of minerals, organic matter and fire ash) aerosols. Rainout of marine aerosols decreases away from the coast. The delivery of marine aerosols (Cl, Na, SO4and Mg) corresponds with summer southerly winds from the ocean and windblown dust (SO4,Mg, Ca and K) is delivered through winter northerly winds from the continental interior. Remineralization of organic matter, dissolution of fire ash and chemical weathering of clay minerals derived from the bedrock and from windblown minerals provide additional sources of nutrients to the vegetation. Salts accumulated within and on top of soil surfaces during the dry summer period are washed into streams during the wet winter months. Afromontane forests occur within deep rocky ravines cut by mountain streams and are protected from fire. The afromontane vegetation did not burn during the fire and benefited from the release of nutrients but regrowth of fynbos on open burnt slopes was slow and most of the released nutrients were lost via streams. Fynbos regrowth largely reflected the hydrology of the study area and corresponded to the pre-fire distribution of biomass with relatively low biomass on mountain ridges and slopes in comparison to lower slopes and valley floors, particularly along stream banks. The removal of above ground plant biomass increased streamflow from the reduction in transpiration and rainfall interception by plants. Hydrophobicity in soils increased following the fire leading to partially burnt organic plant debris being washed down slope to accumulate on the lower slopes and stream valley floors. The geochemical results of this study provide insights on the climate-hydrology-soil interactions of the fynbos ecosystem and its unusually rich biodiversity. The resetting of the ecosystem every 20 to 40 years by fire and the interaction between atmospheric processes and hydrology likely enhances its long term survival.

Vulnerability and Resilience of Temperate Forest Landscapes to Broad-Scale Deforestation in Response to Changing Fire Regimes and Altered Post-Fire Vegetation Dynamics

NASA Astrophysics Data System (ADS)

Tepley, A. J.; Veblen, T. T.; Perry, G.; Anderson-Teixeira, K. J.

2015-12-01

In the face of on-going climatic warming and land-use change, there is growing concern that temperate forest landscapes could be near a tipping point where relatively small changes to the fire regime or altered post-fire vegetation dynamics could lead to extensive conversion to shrublands or savannas. To evaluate vulnerability and resilience to such conversion, we develop a simple model based on three factors we hypothesize to be key in predicting temperate forest responses to changing fire regimes: (1) the hazard rate (i.e., the probability of burning in the next year given the time since the last fire) in closed-canopy forests, (2) the hazard rate for recently-burned, open-canopy vegetation, and (3) the time to redevelop canopy closure following fire. We generate a response surface representing the proportions of the landscape potentially supporting closed-canopy forest and non-forest vegetation under nearly all combinations of these three factors. We then place real landscapes on this response surface to assess the type and magnitude of changes to the fire regime that would drive extensive forest loss. We show that the deforestation of much of New Zealand that followed initial human colonization and the introduction of a new ignition source ca. 750 years ago was essentially inevitable due to the slow rate of forest recovery after fire and the high flammability of post-fire vegetation. In North America's Pacific Northwest, by contrast, a predominantly forested landscape persisted despite two periods of widespread burning in the recent past due in large part to faster post-fire forest recovery and less pronounced differences in flammability between forests and the post-fire vegetation. We also assess the factors that could drive extensive deforestation in other regions to identify where management could reduce this potential and to guide field and modeling work to better understand the responses and ecological feedbacks to changing fire regimes.

Linking chemical elements in forest floor humus (Oh-horizon) in the Czech Republic to contamination sources.

PubMed

Sucharova, Julie; Suchara, Ivan; Hola, Marie; Reimann, Clemens; Boyd, Rognvald; Filzmoser, Peter; Englmaier, Peter

2011-05-01

While terrestrial moss and other plants are frequently used for environmental mapping and monitoring projects, data on the regional geochemistry of humus are scarce. Humus, however, has a much larger life span than any plant material. It can be seen as the "environmental memory" of an area for at least the last 60-100 years. Here concentrations of 39 elements determined by ICP-MS and ICP AES, pH and ash content are presented for 259 samples of forest floor humus collected at an average sample density of 1 site/300 km2 in the Czech Republic. The scale of anomalies linked to known contamination sources (e.g., lignite mining and burning, metallurgical industry, coal fired power plants, metal smelters) is documented and discussed versus natural processes influencing humus quality. Most maps indicate a local impact from individual contamination sources: often more detailed sampling than used here would be needed to differentiate between likely sources. Copyright © 2011 Elsevier Ltd. All rights reserved.

The relationship of post-fire white ash cover to surface fuel consumption

Treesearch

Andrew T. Hudak; Roger D. Ottmar; Robert E. Vihnanek; Nolan W. Brewer; Alistair M. S. Smith; Penelope Morgan

2013-01-01

White ash results from the complete combustion of surface fuels, making it a logically simple retrospective indicator of surface fuel consumption. However, the strength of this relationship has been neither tested nor adequately demonstrated with field measurements. We measured surface fuel loads and cover fractions of white ash and four other surface materials (green...

Effects of fire and post-fire salvage logging on avian communities in conifer-dominated forests of the western United States

USGS Publications Warehouse

Kotliar, N.B.; Hejl, S.J.; Hutto, R.L.; Saab, V.; Melcher, Cynthia; McFadzen, M.E.; George, T.L.; Dobkin, D.S.

2002-01-01

Historically, fire was one of the most widespread natural disturbances in the western United States. More recently, however, significant anthropogenic activities, especially fire suppression and silvicultural practices, have altered fire regimes; as a result, landscapes and associated communities have changed as well. Herein, we review current knowledge of how fire and postfire salvaging practices affect avian communities in conifer-dominated forests of the western United States. Specifically, we contrast avian communities in (1) burned vs. unburned forest, and (2) unsalvaged vs. salvage-logged burns. We also examine how variation in burn characteristics (e.g., severity, age, size) and salvage logging can alter avian communities in burns.Of the 41 avian species observed in three or more studies comparing early postfire and adjacent unburned forests, 22% are consistently more abundant in burned forests, 34% are usually more abundant in unburned forests, and 44% are equally abundant in burned and unburned forests or have varied responses. In general, woodpeckers and aerial foragers are more abundant in burned forest, whereas most foliage-gleaning species are more abundant in unburned forests. Bird species that are frequently observed in stand-replacement burns are less common in understory burns; similarly, species commonly observed in unburned forests often decrease in abundance with increasing burn severity. Granivores and species common in open-canopy forests exhibit less consistency among studies. For all species, responses to tire may be influenced by a number of factors including burn severity, fire size and shape, proximity to unburned forests, pre-and post-fire cover types, and time since fire. In addition, postfire management can alter species’ responses to burns. Most cavity-nesting species do not use severely salvaged burns, whereas some cavity-nesters persist in partially salvaged burns. Early post fire specialists, in particular, appear to prefer unsalvaged burns. We discuss several alternatives to severe salvage-logging that will help provide habitat for cavity nesters.We provide an overview of critical research questions and design considerations crucial for evaluating the effects of prescribed fire and other anthropogenic disturbances, such as forest fragmentation. Management of native avifaunas may be most successful if natural disturbance regimes, including fire, are permitted to occur when possible. Natural fires could be augmented with practices, such as prescribed fire (including high-severity fire), that mimic inherent disturbance regimes.

Real time forest fire warning and forest fire risk zoning: a Vietnamese case study

NASA Astrophysics Data System (ADS)

Chu, T.; Pham, D.; Phung, T.; Ha, A.; Paschke, M.

2016-12-01

Forest fire occurs seriously in Vietnam and has been considered as one of the major causes of forest lost and degradation. Several studies of forest fire risk warning were conducted using Modified Nesterov Index (MNI) but remaining shortcomings and inaccurate predictions that needs to be urgently improved. In our study, several important topographic and social factors such as aspect, slope, elevation, distance to residential areas and road system were considered as "permanent" factors while meteorological data were updated hourly using near-real-time (NRT) remotely sensed data (i.e. MODIS Terra/Aqua and TRMM) for the prediction and warning of fire. Due to the limited number of weather stations in Vietnam, data from all active stations (i.e. 178) were used with the satellite data to calibrate and upscale meteorological variables. These data with finer resolution were then used to generate MNI. The only significant "permanent" factors were selected as input variables based on the correlation coefficients that computed from multi-variable regression among true fire-burning (collected from 1/2007) and its spatial characteristics. These coefficients also used to suggest appropriate weight for computing forest fire risk (FR) model. Forest fire risk model was calculated from the MNI and the selected factors using fuzzy regression models (FRMs) and GIS based multi-criteria analysis. By this approach, the FR was slightly modified from MNI by the integrated use of various factors in our fire warning and prediction model. Multifactor-based maps of forest fire risk zone were generated from classifying FR into three potential danger levels. Fire risk maps were displayed using webgis technology that is easy for managing data and extracting reports. Reported fire-burnings thereafter have been used as true values for validating the forest fire risk. Fire probability has strong relationship with potential danger levels (varied from 5.3% to 53.8%) indicating that the higher potential risk, the more chance of fire happen. By adding spatial factors to continuous daily updated remote sensing based meteo-data, results are valuable for both mapping forest fire risk zones in short and long-term and real time fire warning in Vietnam. Key words: Near-real-time, forest fire warning, fuzzy regression model, remote sensing.

Using Landsat data to assess fire and burn severity in the North American boreal forest region: an overview and summary of results

Treesearch

Nancy H.F. French; Eric S. Kasischke; Ronald J. Hall; Karen A. Murphy; David L. Verbyla; Elizabeth E. Hoy; Jennifer L. Allen

2008-01-01

There has been considerable interest in the recent literature regarding the assessment of post-fire effects on forested areas within the North American boreal forest. Assessing the physical and ecological effects of fire in boreal forests has far-reaching implications for a variety of ecosystem processes -- such as post-fire forest succession -- and land management...

Forest fires in Pennsylvania.

Treesearch

Donald A. Haines; William A. Main; Eugene F. McNamara

1978-01-01

Describes factors that contribute to forest fires in Pennsylvania. Includes an analysis of basic statistics; distribution of fires during normal, drought, and wet years; fire cause, fire activity by day-of-week; multiple-fire day; and fire climatology.

Laboratory Evaluation of the Toxicity of Systemic Insecticides to Emerald Ash Borer Larvae

Treesearch

Therese M. Poland; Tina M. Ciaramitaro; Deborah G. McCullough

2015-01-01

Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae), an invasive phloem-feeding insect native to Asia, threatens at least 16 North American ash (Fraxinus) species and has killed hundreds of millions of ash trees in landscapes and forests. We conducted laboratory bioassays to assess the relative efficacy...

Prospects for long-term ash survival in the core emerald ash borer mortality zone

Treesearch

Jordan M. Marshall; Andrew J. Storer; Roger Mech; Steven A. Katovich

2011-01-01

Attacking all North American ash species (Fraxinus spp.), emerald ash borer (EAB) (Agrilus planipennis Fairmaire) has caused significant mortality within its introduced range. For other forest pests, host bark plays an important role in infestation density and oviposition behavior. The objectives of this study were to (1) locate...

Estimating outside-bark stem volume to any top diameter for ash in Wisconsin

Treesearch

Paul F. Doruska; Timothy D. Hart

2010-01-01

The future of Wisconsin's estimated 742 million ash trees (5 million of which are in urban settings composing 20 percent of Wisconsin's urban forests) is being considered based on the presence of the emerald ash borer. Part of this discussion includes the stem volumes of these ash trees.

Effects of volcanic ash on the forest canopy insects of Montserrat, West Indies.

PubMed

Marske, Katharine A; Ivie, Michael A; Hilton, Geoff M

2007-08-01

The impact of ash deposition levels on canopy arthropods was studied on the West Indian island of Montserrat, the site of an ongoing volcanic eruption since 1995. Many of the island's natural habitats have been buried by volcanic debris, and remaining forests regularly receive volcanic ash deposition. To test the effect of ash on canopy arthropods, four study sites were sampled over a 15-mo period. Arthropod samples were obtained using canopy fogging, and ash samples were taken from leaf surfaces. Volcanic ash has had a significant negative impact on canopy arthropod populations, but the decline is not shared equally by all taxa present, and total population variation is within the variance attributed to other aboitic and biotic factors. The affected populations do not differ greatly from those of the neighboring island of St. Kitts, which has not been subject to recent volcanic activity. This indicates that observed effects on Montserrat's arthropod fauna have a short-term acute response to recent ash deposition rather than a chronic depression caused by repeated exposure to ash over the last decade.

21st Century drought-related fires counteract the decline of Amazon deforestation carbon emissions.

PubMed

Aragão, Luiz E O C; Anderson, Liana O; Fonseca, Marisa G; Rosan, Thais M; Vedovato, Laura B; Wagner, Fabien H; Silva, Camila V J; Silva Junior, Celso H L; Arai, Egidio; Aguiar, Ana P; Barlow, Jos; Berenguer, Erika; Deeter, Merritt N; Domingues, Lucas G; Gatti, Luciana; Gloor, Manuel; Malhi, Yadvinder; Marengo, Jose A; Miller, John B; Phillips, Oliver L; Saatchi, Sassan

2018-02-13

Tropical carbon emissions are largely derived from direct forest clearing processes. Yet, emissions from drought-induced forest fires are, usually, not included in national-level carbon emission inventories. Here we examine Brazilian Amazon drought impacts on fire incidence and associated forest fire carbon emissions over the period 2003-2015. We show that despite a 76% decline in deforestation rates over the past 13 years, fire incidence increased by 36% during the 2015 drought compared to the preceding 12 years. The 2015 drought had the largest ever ratio of active fire counts to deforestation, with active fires occurring over an area of 799,293 km 2 . Gross emissions from forest fires (989 ± 504 Tg CO 2 year -1 ) alone are more than half as great as those from old-growth forest deforestation during drought years. We conclude that carbon emission inventories intended for accounting and developing policies need to take account of substantial forest fire emissions not associated to the deforestation process.

Are High-Severity Fires Burning at Much Higher Rates Recently than Historically in Dry-Forest Landscapes of the Western USA?

PubMed

Baker, William L

2015-01-01

Dry forests at low elevations in temperate-zone mountains are commonly hypothesized to be at risk of exceptional rates of severe fire from climatic change and land-use effects. Their setting is fire-prone, they have been altered by land-uses, and fire severity may be increasing. However, where fires were excluded, increased fire could also be hypothesized as restorative of historical fire. These competing hypotheses are not well tested, as reference data prior to widespread land-use expansion were insufficient. Moreover, fire-climate projections were lacking for these forests. Here, I used new reference data and records of high-severity fire from 1984-2012 across all dry forests (25.5 million ha) of the western USA to test these hypotheses. I also approximated projected effects of climatic change on high-severity fire in dry forests by applying existing projections. This analysis showed the rate of recent high-severity fire in dry forests is within the range of historical rates, or is too low, overall across dry forests and individually in 42 of 43 analysis regions. Significant upward trends were lacking overall from 1984-2012 for area burned and fraction burned at high severity. Upward trends in area burned at high severity were found in only 4 of 43 analysis regions. Projections for A.D. 2046-2065 showed high-severity fire would generally be still operating at, or have been restored to historical rates, although high projections suggest high-severity fire rotations that are too short could ensue in 6 of 43 regions. Programs to generally reduce fire severity in dry forests are not supported and have significant adverse ecological impacts, including reducing habitat for native species dependent on early-successional burned patches and decreasing landscape heterogeneity that confers resilience to climatic change. Some adverse ecological effects of high-severity fires are concerns. Managers and communities can improve our ability to live with high-severity fire in dry forests.

Fire Impact on Phytomass and Carbon Emissions in the Forests of Siberia

NASA Astrophysics Data System (ADS)

Ivanova, Galina A.; Zhila, Sergei V.; Ivanov, Valery A.; Kovaleva, Nataly M.; Kukavskaya, Elena A.; Platonova, Irina A.; Conard, Susan G.

2014-05-01

Siberian boreal forests contribute considerably to the global carbon budget, since they take up vast areas, accumulate large amount of carbon, and are sensitive to climatic changes. Fire is the main forest disturbance factor, covering up to millions of hectares of boreal forests annually, of which the majority is in Siberia. Carbon emissions released from phytomass burning influence atmospheric chemistry and global carbon cycling. Changing climate and land use influence the number and intensity of wildfires, forest state, and productivity, as well as global carbon balance. Fire effects on forest overstory, subcanopy woody layer, and ground vegetation phytomass were estimated on sites in light-conifer forests of the Central Siberia as a part of the project "The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia" supported by NASA (NEESPI). This study focuses on collecting quantitative data and modeling the influence of fires of varying intensity on fire emissions, carbon budget, and ecosystem processes in coniferous stands. Fires have a profound impact on forest-atmospheric carbon exchange and transform forests from carbon sinks to carbon sources lasting long after the time of burning. Our long-term experiments allowed us to identify vegetation succession patterns in taiga Scots pine stands after fires of known behavior. Estimating fire contributions to the carbon budget requires consideration of many factors, including vegetation type and fire type and intensity. Carbon emissions were found to depend on fire intensity and weather. In the first several years after fire, the above-ground phytomass appeared to be strongly controlled by fire intensity. However, the influence of burning intensity on organic matter accumulation was found to decrease with time.

Short-term responses of birds to prescribed fire in fire-suppressed forests of California

Treesearch

Bagne Karen; Kathryn Purcell

2011-01-01

Prescribed fire is one tool for restoring fire-suppressed forests, but application of fire during spring coincides with breeding and arrival of migrant birds. We examined effects of low-severity prescribed fires on counts of birds in a managed forest in the Sierra Nevada of California immediately, 1 year, and 3–6 years after fire was applied in spring. Of 26 species...

Dry forests of the Northeastern Cascades Fire and Fire Surrogate project site, Mission Creek, Okanogan-Wenatchee National Forest

Treesearch

James K. Agee; John F. (comps.) Lehmkuhl

2009-01-01

The Fire and Fire Surrogate (FFS) project is a large long-term metastudy established to assess the effectiveness and ecological impacts of burning and fire "surrogates" such as cuttings and mechanical fuel treatments that are used instead of fire, or in combination with fire, to restore dry forests. One of the 13 national FFS sites is the Northeastern...

Effectiveness of Prescribed Fire as a Fuel Treatment in Californian Coniferous Forests

Treesearch

Nicole M. Vaillant; JoAnn Fites-Kaufman; Scott L. Stephens

2006-01-01

Effective fire suppression for the past century has altered forest structure and increased fuel loads. Prescribed fire as a fuels treatment can reduce wildfire size and severity. This study investigates how prescribed fire affects fuel loads, forest structure, potential fire behavior, and modeled tree mortality at 80th, 90th, and 97.5th percentile fire weather...

A soil burn severity index for understanding soil-fire relations in tropical forests

Treesearch

Theresa B. Jain; William A. Gould; Russell T. Graham; David S. Pilliod; Leigh B. Lentile; Grizelle Gonzalez

2008-01-01

Methods for evaluating the impact of fires within tropical forests are needed as fires become more frequent and human populations and demands on forests increase. Short- and long-term fire effects on soils are determined by the prefire, fire, and postfire environments. We placed these components within a fire-disturbance continuum to guide our literature synthesis and...

Aerosol emissions from forest and grassland burnings in the southern amazon basin and central Brazil

NASA Astrophysics Data System (ADS)

Leslie, Alistair C. D.

1981-03-01

Forest and grassland clearing by means of prescribed fires in tropical areas of the world may be responsible for large inputs of fine particulates to the global atmosphere besides being a major source of trace gases. The major continents on which extensive biomass burning takes place are Africa and South America. Such agricultural practices of burning have been employed throughout man's existence, but the importance and significance of such burning relative to anthropogenic industrial emissions to the atmosphere has not until extremely recently been seriously studied. In August-September 1979 project "Brushfire 1979" took place based in Brasília, Brazil. The Air Quality Division of the National Center for Atmospheric Research made ground level and aircraft measurements of trace gases (e.g. CO 2, CO, CH 4, N 2O, H 2, CH 3Cl, COS, NO, NO 2, O 3) and Florida State University sampled ground level aerosol emissions from grass and forest burnings. Aerosols were sampled using plastic 7-stage single orifice cascade impactors and FSU type linear and circular "streakers". Long term sampling was made of regional background for total particulates (<15 μmad) with 2 h resolution using streakers and with impactors for 24 h resolution of 7 particle size fractions (<0.25 to >8 μmad). Short term sampling within grass or forest fires was made using impactors incorporated into portable kits containing 4 miniature 12-18 V dc Brailsford pumps and a disposable dry cell power pack. Sampling times of 5-15 min were found optimal under these conditions. Grass fires were sampled in the savannah area northeast of Brasília and forest fires in the state of Mato Grosso on the southern edge of the dryland forest of the Amazon basin. Residual ash samples were collected. All of the samples were analyzed at Florida State University using PIXE for 15-20 elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb and Sr. Computer reduction of the X-ray spectra was made using the "HEXB" program. One of the prominent features found was the large flux of small particles (<2.0 μm) from both fire types. P, S and Cl were mostly small particle, Mg, Al, Si and K showed a bimodal distribution biased towards the small particle range, while Ca, Ti and Fe (crustal elements) predominated in the large particle mode. As Cl was found to be exclusively small particle, a formation mechanism in which HCl gas neutralizes small organic particles containing P and S may be hypothesized. A much more extensive field program for the summer of 1980 is planned to take place in the central Amazon basin using ground and airborne aerosol samplers, to capitalize on the work pioneered in this study.

Glare-reducing goggles for lookouts.

Treesearch

Richard E. McArdle; William G. Morris; Thornton T. Munger

1936-01-01

Detection of forest fires while they are still small is so important in forest protection that studies of the visibility of forest fire smokes from lookout points has been one of the principal phases of the fire studies program of the Pacific Northwest Forest Experiment Station. One phase of fire detection is the personal efficiency of the lookout. The Station has...

Influence of wildfires in the boreal forests of Eastern Siberia on atmospheric aerosol parameters

NASA Astrophysics Data System (ADS)

Tomshin, Oleg A.; Solovyev, Vladimir S.

2017-11-01

The results of studies of the dynamics of forest fires in the boreal forests of Yakutia (Eastern Siberia) for 2001-2016 are presented. Variations of aerosol optical thickness (AOT), aerosol index (AI) and total carbon monoxide content during May-September were studied depending on the different forest fire activity level. It is shown that the seasonal variations of AOT, AI and CO in the most fire-dangerous years differ significantly from the fire seasons when forest fire activity was medium or low.

Broadleaf deciduous forest counterbalanced the direct effect of climate on Holocene fire regime in hemiboreal/boreal region (NE Europe)

NASA Astrophysics Data System (ADS)

Feurdean, Angelica; Veski, Siim; Florescu, Gabriela; Vannière, Boris; Pfeiffer, Mirjam; O'Hara, Robert B.; Stivrins, Normunds; Amon, Leeli; Heinsalu, Atko; Vassiljev, Jüri; Hickler, Thomas

2017-08-01

Disturbances by fire are essential for the functioning of boreal/hemiboreal forests, but knowledge of long-term fire regime dynamics is limited. We analysed macrocharcoal morphologies and pollen of a sediment record from Lake Lielais Svētiņu (eastern Latvia), and in conjunction with fire traits analysis present the first record of Holocene variability in fire regime, fuel sources and fire types in boreal forests of the Baltic region. We found a phase of moderate to high fire activity during the cool and moist early (mean fire return interval; mFRI of ∼280 years; 11,700-7500 cal yr BP) and the late (mFRI of ∼190 years; 4500-0 cal yr BP) Holocene and low fire activity (mFRI of ∼630 years) during the Holocene Thermal Optimum (7500-4500 cal yr BP). Charcoal morphotypes and the pollen record show the predominance of frequent surface fires, occasionally transitioning to the crown during Pinus sylvestris-Betula boreal forests and less frequent surface fires during the dominance of temperate deciduous forests. In contrast to the prevailing opinion that fires in boreal forests are mostly low to moderate severity surface fires, we found evidence for common occurrence of stand-replacing crown fires in Picea abies canopy. Our results highlight that charcoal morphotypes analysis allows for distinguishing the fuel types and surface from crown fires, therefore significantly advancing our interpretation of fire regime. Future warmer temperatures and increase in the frequency of dry spells and abundant biomass accumulation can enhance the fire risk on the one hand, but will probably promote the expansion of broadleaf deciduous forests to higher latitudes, on the other hand. By highlighting the capability of broadleaf deciduous forests to act as fire-suppressing landscape elements, our results suggest that fire activity may not increase in the Baltic area under future climate change.

Use of isotopic and hydrometric monitoring methods to partition hydrologic contributions to forested wetlands in the Upper Peninsula of Michigan

NASA Astrophysics Data System (ADS)

Van Grinsven, M. J.; Pypker, T. G.; Kolka, R. K.

2012-12-01

As a result of their landscape position and physical soil properties, northern forested wetlands are capable of retaining springtime snowmelt, rain and near surface groundwater inputs into the growing season. Hydrological conditions such as source water chemistry, duration of inundation, and magnitude of water table fluctuations are affected by the relative contribution of snow, rain, and groundwater sources, and in turn these hydrological conditions strongly influence the structure and function of northern forested wetlands. Black ash (Fraxinus nigra) is a facultative wet tree species, and is known to occur in 23 U.S. states and 7 Canadian provinces in northeastern North America. Black ash trees have ecological, economic, and cultural significance, and are currently threatened by the rapid expansion of the exotic emerald ash borer (Burprestidae: Agrilus planipennis). Since its initial detection in 2002 near Detroit, MI, the emerald ash borer has killed millions of ash trees in 15 U.S. states and 2 Canadian provinces. There is very little known about black ash wetland hydrology and ecology, and as a result of the looming infestation, there is a critical need to gain a better understanding of the hydrology in undisturbed ecosystems. The main objective of this study is to partition source water contributions in black ash wetlands in the western Upper Peninsula of Michigan. We hypothesize that snowmelt and near surface groundwater supply the majority of water to these wetlands annually, and summer rain is readily removed from the system through the evapotranspiration pathway. Hydrometric monitoring methods were used in conjunction with isotopic analysis using a linear mixing model to characterize source water contributions in nine black ash wetlands. The results suggest a connection with near surface groundwater during spring and early summer, and a short residence time for rain water following summer storm events. The outcome of this research aims to inform land managers in northeastern North America about the natural hydrologic condition of black ash wetlands, and provide baseline data that underscores potential water and forest resource impacts of current and future emerald ash borer infestations.

Patterns of Coarse Woody Debris in Hardwood Forests across a Chronosequence of Ash Mortality Due to the Emerald Ash Borer (Agrilus planipennis)

Treesearch

Matt Higham; Brian M. Hoven; David L. Gorchov; Kathleen S. Knight

2017-01-01

The invasive emerald ash borer (Agrilus planipennis) (EAB) is causing widespread ash (Fraxinus spp.) mortality in 25 U.S. states and two Canadian provinces. We investigated the impact of EAB on coarse woody debris (CWD) volume across 24 sites in western and central Ohio, USA, representing a chronosequence of ash mortality,...

Ash cap influences on site productivity and fertilizer response in forests of the Inland Northwest

Treesearch

Mariann T. Garrison-Johnston; Peter G. Mika; Dan L. Miller; Phil Cannon; Leonard R. Johnson

2007-01-01

Data from 139 research sites throughout the Inland Northwest were analyzed for effects of ash cap on site productivity, nutrient availability and fertilization response. Stand productivity and nitrogen (N) fertilizer response were greater on sites with ash cap than on sites without. Where ash was present, depth of ash had no effect on site productivity or N fertilizer...

Prediction of forest fires occurrences with area-level Poisson mixed models.

PubMed

Boubeta, Miguel; Lombardía, María José; Marey-Pérez, Manuel Francisco; Morales, Domingo

2015-05-01

The number of fires in forest areas of Galicia (north-west of Spain) during the summer period is quite high. Local authorities are interested in analyzing the factors that explain this phenomenon. Poisson regression models are good tools for describing and predicting the number of fires per forest areas. This work employs area-level Poisson mixed models for treating real data about fires in forest areas. A parametric bootstrap method is applied for estimating the mean squared errors of fires predictors. The developed methodology and software are applied to a real data set of fires in forest areas of Galicia. Copyright © 2015 Elsevier Ltd. All rights reserved.

Applicability of the mixture of bituminous coal and anthracite to conventional pulverized coal firing boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takano, Shin-Ichi; Kiga, Takashi; Miyamae, Shigehiro

1994-12-31

In some future, it is expected for Japanese power stations to be hard to get a high-grade coal like a bituminous coal. We conducted therefore pilot scale tests of pulverized blends of bituminous coal and anthracite using a 1.2MWt tunnel furnace in order to evaluate the applicability of the blends of bituminous coal and anthracite to conventional pulverized coal firing boilers. One kind of bituminous coal and two kinds of anthracite, one was of low ash content and another was of high ash content, were prepared for the test. Previously to pilot scale tests, coal properties and ash properties ofmore » the blends of bituminous coal and anthracite were analyzed to estimate the characteristics of combustion, ash deposition, and so on. In the test, we investigated the combustion efficiency, NOx emission, characteristics of ignition stability and grindability changing the blend rate of anthracite. Results of our study indicated that the critical restrictions on the blending rate of anthracite were unburnt carbon in fly ash and NOx emission as for coals tested. The acceptable limitation on blending rate of anthracite was 10 and 20%, respectively for two kinds of conventional pulverized coal fired boiler. Concerning to the grindability, it became worse with increasing the blending rate of anthracite from grindability test using a roller mill, while it became better estimating from HGI.« less

Severity of an uncharacteristically large wildfire, the Rim Fire, in forests with relatively restored frequent fire regimes

Treesearch

Jamie Lydersen; Malcolm North; Brandon M. Collins

2014-01-01

The 2013 Rim Fire, originating on Forest Service land, burned into old-growth forests within Yosemite National Park with relatively restored frequent-fire regimes (¡Ý2 predominantly low and moderate severity burns within the last 35 years). Forest structure and fuels data were collected in the field 3-4 years before the fire, providing a rare chance to use pre-existing...

The forest fire season at different elevations in Idaho

Treesearch

J. A. Larsen

1925-01-01

In any fire-ridden forest region, such as north Idaho, there is great need for a tangible basis by which to judge the length and the intensity of the fire season in different forest types and at different elevations. The major and natural forest types, such as the western yellow pine forests, the western white-pine forests, and the subalpine forests occur in...

Seed invasion filters and forest fire severity

Treesearch

Tom R. Cottrell; Paul F. Hessburg; Jonathan A. Betz

2008-01-01

Forest seed dispersal is altered after fire. Using seed traps, we studied impacts of fire severity on timing of seed dispersal, total seed rain, and seed rain richness in patches of high and low severity fire and unburned Douglas-fir (Pseudotsuga menziesii) forests in the Fischer and Tyee fire complexes in the eastern Washington Cascades. Unburned...

Historical fire regime and forest variability on two eastern Great Basin fire-sheds (USA)

Treesearch

Stanley G. Kitchen

2012-01-01

Proper management of naturally forested landscapes requires knowledge of key disturbance processes and their effects on species composition and structure. Spatially-intensive fire and forest histories provide valuable information about how fire and vegetation may vary and interact on heterogeneous landscapes. I constructed 800-year fire and tree recruitment...

Overall evaluation of combustion and NO(x) emissions for a down-fired 600 MW(e) supercritical boiler with multiple injection and multiple staging.

PubMed

Kuang, Min; Li, Zhengqi; Liu, Chunlong; Zhu, Qunyi

2013-05-07

To achieve significant reductions in NOx emissions and to eliminate strongly asymmetric combustion found in down-fired boilers, a deep-air-staging combustion technology was trialed in a down-fired 600 MWe supercritical utility boiler. By performing industrial-sized measurements taken of gas temperatures and species concentrations in the near wing-wall region, carbon in fly ash and NOx emissions at various settings, effects of overfire air (OFA) and staged-air damper openings on combustion characteristics, and NOx emissions within the furnace were experimentally determined. With increasing the OFA damper opening, both fluctuations in NOx emissions and carbon in fly ash were initially slightly over OFA damper openings of 0-40% but then lengthened dramatically in openings of 40-70% (i.e., NOx emissions reduced sharply accompanied by an apparent increase in carbon in fly ash). Decreasing the staged-air declination angle clearly increased the combustible loss but slightly influenced NOx emissions. In comparison with OFA, the staged-air influence on combustion and NOx emissions was clearly weaker. Only at a high OFA damper opening of 50%, the staged-air effect was relatively clear, i.e., enlarging the staged-air damper opening decreased carbon in fly ash and slightly raised NOx emissions. By sharply opening the OFA damper to deepen the air-staging conditions, although NOx emissions could finally reduce to 503 mg/m(3) at 6% O2 (i.e., an ultralow NOx level for down-fired furnaces), carbon in fly ash jumped sharply to 15.10%. For economical and environment-friendly boiler operations, an optimal damper opening combination (i.e., 60%, 50%, and 50% for secondary air, staged-air, and OFA damper openings, respectively) was recommended for the furnace, at which carbon in fly ash and NOx emissions attained levels of about 10% and 850 mg/m(3) at 6% O2, respectively.

Electrical Resistivity Tomography for coal fire mapping over Jharia coal field, India

NASA Astrophysics Data System (ADS)

Pal, S. K.; Kumar, S.; Bharti, A. K.; Pathak, V. K.; Kumar, R.

2016-12-01

Over the decades, coal fires are serious global concern posing grievous hazards to the valuable energy resources, local environments and human life. The coal seam and coal mine fires may be initiated due to improper mining activities, exothermic reactions, lighting, forest fire and other anthropic activities, which burn the coal and may continue underground for decades. The burning of concealed coal seams is a complex process involving numerous ill-defined parameters. Generally, the coal exhibits resistivity of 100 to 500Ωm at normal temperature conditions. During the pyrolysis process, at temperatures greater than 6500C coal became a good conductor with a resistivity of approximately 1 Ωm. The present study deals with the mapping of coal fire over Jharia coal field, India using Electrical Resistivity Tomography (ERT). A state-of-the-art 61-channel 64 electrode FlashRES-Universal ERT data acquisition system has been used for data acquisition in the field. The ERT data have been collected using Gradient array and processed in FlashRES Universal survey data checking program for removing noisy data. Then, filtered output data have been inverted using a 2.5D resistivity inversion program. Low resistivity anomalies over 80m-125m and 320m-390m along the profile are inferred to be active coal fire in seam- XVI at a depth of 25m -35m(Figure 1). High resistivity anomaly over 445m - 510m at a depth of 25m -35m has been delineated, due to void associated with complete combustion of seam- XVI coal, followed by char and ash formation resulting from the coal seam fire. Results prove the efficacy of the ERT study comprising Gradient array for coal fire mapping over, Jharia coal field, India.

Effects of repeated fires on ecosystem C and N stocks along a fire induced forest/grassland gradient

NASA Astrophysics Data System (ADS)

Cheng, Chih-Hsin; Chen, Yung-Sheng; Huang, Yu-Hsuan; Chiou, Chyi-Rong; Lin, Chau-Chih; Menyailo, Oleg V.

2013-03-01

Repeated fires might have different effect on ecosystem carbon storage than a single fire event, but information on repeated fires and their effects on forest ecosystems and carbon storage is scarce. However, changes in climate, vegetation composition, and human activities are expected to make forests more susceptible to fires that recur with relatively high frequency. In this study, the effects of repeated fires on ecosystem carbon and nitrogen stocks were examined along a fire-induced forest/grassland gradient wherein the fire events varied from an unburned forest to repeatedly burned grassland. Results from the study show repeated fires drastically decreased ecosystem carbon and nitrogen stocks along the forest/grassland gradient. The reduction began with the disappearance of living tree biomass, and followed by the loss of soil carbon and nitrogen. Within 4 years of the onset of repeated fires on the unburned forest, the original ecosystem carbon and nitrogen stocks were reduced by 42% and 21%, respectively. Subsequent fires caused cumulative reductions in ecosystem carbon and nitrogen stocks by 68% and 44% from the original ecosystem carbon and nitrogen stocks, respectively. The analyses of carbon budgets calculated by vegetation composition and stable isotopic δ13C values indicate that 84% of forest-derived carbon is lost at grassland, whereas the gain of grass-derived carbon only compensates 18% for this loss. Such significant losses in ecosystem carbon and nitrogen stocks suggest that the effects of repeated fires have substantial impacts on ecosystem and soil carbon and nitrogen cycling.

Landscape-scale effects of fire severity on mixed-conifer and red fir forest structure in Yosemite National Park

USGS Publications Warehouse

Kane, Van R.; Lutz, James A.; Roberts, Susan L.; Smith, Douglas F.; McGaughey, Robert J.; Povak, Nicholas A.; Brooks, Matthew L.

2013-01-01

While fire shapes the structure of forests and acts as a keystone process, the details of how fire modifies forest structure have been difficult to evaluate because of the complexity of interactions between fires and forests. We studied this relationship across 69.2 km2 of Yosemite National Park, USA, that was subject to 32 fires ⩾40 ha between 1984 and 2010. Forests types included ponderosa pine (Pinus ponderosa), white fir-sugar pine (Abies concolor/Pinus lambertiana), and red fir (Abies magnifica). We estimated and stratified burned area by fire severity using the Landsat-derived Relativized differenced Normalized Burn Ratio (RdNBR). Airborne LiDAR data, acquired in July 2010, measured the vertical and horizontal structure of canopy material and landscape patterning of canopy patches and gaps. Increasing fire severity changed structure at the scale of fire severity patches, the arrangement of canopy patches and gaps within fire severity patches, and vertically within tree clumps. Each forest type showed an individual trajectory of structural change with increasing fire severity. As a result, the relationship between estimates of fire severity such as RdNBR and actual changes appears to vary among forest types. We found three arrangements of canopy patches and gaps associated with different fire severities: canopy-gap arrangements in which gaps were enclosed in otherwise continuous canopy (typically unburned and low fire severities); patch-gap arrangements in which tree clumps and gaps alternated and neither dominated (typically moderate fire severity); and open-patch arrangements in which trees were scattered across open areas (typically high fire severity). Compared to stands outside fire perimeters, increasing fire severity generally resulted first in loss of canopy cover in lower height strata and increased number and size of gaps, then in loss of canopy cover in higher height strata, and eventually the transition to open areas with few or no trees. However, the estimated fire severities at which these transitions occurred differed for each forest type. Our work suggests that low severity fire in red fir forests and moderate severity fire in ponderosa pine and white fir-sugar pine forests would restore vertical and horizontal canopy structures believed to have been common prior to the start of widespread fire suppression in the early 1900s. The fusion of LiDAR and Landsat data identified post-fire structural conditions that would not be identified by Landsat alone, suggesting a broad applicability of combining Landsat and LiDAR data for landscape-scale structural analysis for fire management.

Fire performance in traditional silvicultural and fire and fire surrogate treatments in Sierran mixed-conifer forests: a brief summary

Treesearch

Jason J. Moghaddas; Scott L. Stephens

2007-01-01

Mixed conifer forests cover 7.9 million acres of California’s total land base. Forest structure in these forests has been influenced by harvest practices and silvicultural systems implemented since the beginning of the California Gold Rush in 1849. Today, the role of fire in coniferous forests, both in shaping past stand structure and its ability to shape future...

MODIS NDVI Response Following Fires in Siberia

NASA Technical Reports Server (NTRS)

Ranson, K. Jon; Sun, G.; Kovacs, K.; Kharuk, V. I.

2003-01-01

The Siberian boreal forest is considered a carbon sink but may become an important source of carbon dioxide if climatic warming predictions are correct. The forest is continually changing through various disturbance mechanisms such as insects, logging, mineral exploitation, and especially fires. Patterns of disturbance and forest recovery processes are important factors regulating carbon flux in this area. NASA's Terra MODIS provides useful information for assessing location of fires and post fire changes in forests. MODIS fire (MOD14), and NDVI (MOD13) products were used to examine fire occurrence and post fire variability in vegetation cover as indicated by NDVI. Results were interpreted for various post fire outcomes, such as decreased NDVI after fire, no change in NDVI after fire and positive NDVI change after fire. The fire frequency data were also evaluated in terms of proximity to population centers, and transportation networks.

A heuristic expert system for forest fire guidance in Greece.

PubMed

Iliadis, Lazaros S; Papastavrou, Anastasios K; Lefakis, Panagiotis D

2002-07-01

Forests and forestlands are common inheritance for all Greeks and a piece of the national wealth that must be handed over to the next generations in the best possible condition. After 1974, Greece faces a severe forest fire problem and forest fire forecasting is the process that will enable the Greek ministry of Agriculture to reduce the destruction. This paper describes the basic design principles of an Expert System that performs forest fire forecasting (for the following fire season) and classification of the prefectures of Greece into forest fire risk zones. The Expert system handles uncertainty and uses heuristics in order to produce scenarios based on the presence or absence of various qualitative factors. The initial research focused on the construction of a mathematical model which attempted to describe the annual number of forest fires and burnt area in Greece based on historical data. However this has proven to be impossible using regression analysis and time series. A closer analysis of the fire data revealed that two qualitative factors dramatically affect the number of forest fires and the hectares of burnt areas annually. The first is political stability and national elections and the other is drought cycles. Heuristics were constructed that use political stability and drought cycles, to provide forest fire guidance. Fuzzy logic was applied to produce a fuzzy expected interval for each prefecture of Greece. A fuzzy expected interval is a narrow interval of values that best describes the situation in the country or a part of the country for a certain time period. A successful classification of the prefectures of Greece in forest fire risk zones was done by the system, by comparing the fuzzy expected intervals to each other. The system was tested for the years 1994 and 1995. The testing has clearly shown that the system can predict accurately, the number of forest fires for each prefecture for the following year. The average accuracy was as high as 85.25% for 1995 and 80.89% for 1994. This makes the Expert System a very important tool for forest fire prevention planning.

Chemical composition and properties of ashes from combustion plants using Miscanthus as fuel.

PubMed

Lanzerstorfer, Christof

2017-04-01

Miscanthus giganteus is one of the energy crops considered to show potential for a substantial contribution to sustainable energy production. In the literature there is little data available about the chemical composition of ashes from the combustion of Miscanthus and practically no data about their physical properties. However, for handling, treatment and utilization of the ashes this information is important. In this study ashes from two biomass combustion plants using Miscanthus as fuel were investigated. The density of the ashes was 2230±35kg/m 3 , which was similar to the density of ashes from straw combustion. Also the bulk densities were close to those reported for straw ashes. The flowability of the ashes was a little worse than the flowability of ashes from wood combustion. The measured heavy metal concentrations were below the usual limits for utilization of the ashes as soil conditioner. The concentrations in the bottom ash were similar to those reported for ash from forest residue combustion plants. In comparison with cyclone fly ashes from forest residue combustion the measured heavy metal concentrations in the cyclone fly ash were considerably lower. Cl - , S and Zn were enriched in the cyclone fly ash which is also known for ashes from wood combustion. In comparison with literature data obtained from Miscanthus plant material the concentrations of K, Cl - and S were lower. This can be attributed to the fact that the finest fly ash is not collected by the cyclone de-dusting system of the Miscanthus combustion plants. Copyright © 2016. Published by Elsevier B.V.

The oxidation of Cr(III) to Cr(VI) in the environment by atmospheric oxygen during the bush fires.

PubMed

Panichev, N; Mabasa, W; Ngobeni, P; Mandiwana, K; Panicheva, S

2008-05-30

The presence of Cr(VI) in soils and plants of remote unpolluted areas can be explained by partial oxidation of Cr(III) with atmospheric oxygen during seasonable bush fires, which are rather frequent event in South Africa. Experiments with thermal treatment of a veld grass, Hyperthelia dissoluta, in muffle furnace at high temperature, followed by electrothermal atomic absorption spectrometry (ETAAS) determination of chromium, show a remarkable increase in Cr(VI) concentration from initial 2.5 to 23.2% after the treatment of grass ash at 500 degrees C and to 58.1% at 900 degrees C. Before ETAAS determination, the two chromium species of interest were separated by the treatment of samples with 0.1M Na2CO3. Thermodynamic calculations confirm the possibility of Cr(III) to Cr(VI) oxidation with atmospheric oxygen at high temperature in alkaline media, which is typical for vegetation ash. Analysis of field samples show that percent of Cr(VI), in respect to the total amount of chromium increased from initial 2.5% in grass to 9.3% in ash of grass. Without oxidation the percent of Cr(VI) in grass and ash of grass should be a constant value. After the fire Cr(VI) concentration in top soil (0-3 cm) increased from 0.3+/-0.05 to 1.8+/-0.5 microg g(-1) and the total Cr from 26+/-9 to 69+/-14 microg g(-1). The reason for the appearance of additional amount of Cr on top soil can be explained by condensation of chromium species from flame and shouldering ash on a soil surface. The results of studies demonstrate that Cr(VI) is formed by Cr(III) oxidation with atmospheric oxygen at high temperature during bush fires.

Combustion influences on natural abundance nitrogen isotope ratio in soil and plants following a wildfire in a sub-alpine ecosystem.

PubMed

Huber, Edith; Bell, Tina L; Adams, Mark A

2013-11-01

This before-and-after-impact study uses the natural abundance N isotope ratio (δ(15)N) to investigate the effects of a wildfire on sub-alpine ecosystem properties and processes. We measured the (15)N signatures of soil, charred organic material, ash and foliage in three sub-alpine plant communities (grassland, heathland and woodland) in south-eastern Australia. Surface bulk soil was temporarily enriched in (15)N immediately after wildfire compared to charred organic material and ash in all plant communities. We associated the enrichment of bulk soil with fractionation of N during combustion and volatilization of N, a process that also explains the sequential enrichment of (15)N of unburnt leaves > ash > charred organic material in relation to duration and intensity of heating. The rapid decline in (15)N of bulk soil to pre-fire values indicates that depleted ash, containing considerable amounts of total N, was readily incorporated into the soil. Foliar δ(15)N also increased with values peaking 1 year post-fire. Foliar enrichment was foremost coupled with the release of enriched NH4(+) into the soil owing to isotopic discrimination during volatilization of soluble N and combustion of organic material. The mode of post-fire regeneration influenced foliar (15)N enrichment in two species indicating use of different sources of N following fire. The use of natural abundance of (15)N in soil, ash and foliage as a means of tracing transformation of N during wildfire has established the importance of combustion products as an important, albeit temporary source of inorganic N for plants regenerating after wildfire.

Synergy between land use and climate change increases future fire risk in Amazon forests

NASA Astrophysics Data System (ADS)

Le Page, Yannick; Morton, Douglas; Hartin, Corinne; Bond-Lamberty, Ben; Cardoso Pereira, José Miguel; Hurtt, George; Asrar, Ghassem

2017-12-01

Tropical forests have been a permanent feature of the Amazon basin for at least 55 million years, yet climate change and land use threaten the forest's future over the next century. Understory forest fires, which are common under the current climate in frontier forests, may accelerate Amazon forest losses from climate-driven dieback and deforestation. Far from land use frontiers, scarce fire ignitions and high moisture levels preclude significant burning, yet projected climate and land use changes may increase fire activity in these remote regions. Here, we used a fire model specifically parameterized for Amazon understory fires to examine the interactions between anthropogenic activities and climate under current and projected conditions. In a scenario of low mitigation efforts with substantial land use expansion and climate change - Representative Concentration Pathway (RCP) 8.5 - projected understory fires increase in frequency and duration, burning 4-28 times more forest in 2080-2100 than during 1990-2010. In contrast, active climate mitigation and land use contraction in RCP4.5 constrain the projected increase in fire activity to 0.9-5.4 times contemporary burned area. Importantly, if climate mitigation is not successful, land use contraction alone is very effective under low to moderate climate change, but does little to reduce fire activity under the most severe climate projections. These results underscore the potential for a fire-driven transformation of Amazon forests if recent regional policies for forest conservation are not paired with global efforts to mitigate climate change.

A dendrochronology based fire history of Jeffry pine-mixed conifer forests in the Sierra San Pedro Martir, Mexico

Treesearch

Scott L. Stephens; Carl N. Skinner; Samantha J. Gill

2003-01-01

Conifer forests in northwestern Mexico have not experienced systematic fire suppression or logging, making them unique in western North America. Fire regimes of Pinus jeffreyi Grev. & Balf. mixed conifer forests in the Sierra San Pedro Martir, Baja California, Mexico, were determined by identifying 105 fire dates from 1034 fire scars in 105 specimens. Fires were...

Initial tree regeneration responses to fire and thinning treatments in a Sierra Nevada mixed-conifer forest, USA

Treesearch

Harold S.J. Zald; Andrew N. Gray; Malcolm North; Ruth A. Kern

2008-01-01

Fire is a driver of ecosystem patterns and processes in forests globally, but natural fire regimes have often been altered by decades of active fire management. Following almost a century of fire suppression, many Western U.S. forests have greater fuel levels, higher tree densities, and are now dominated by fire-sensitive, shade-tolerant species. These fuel-loaded...

A soil burn severity index for understanding soil-fire relations in tropical forests [Chinese version

Treesearch

Theresa B. Jain; William A. Gould; Russell T. Graham; David S. Pilliod; Leigh B. Lentile; Grizelle Gonzalez

2008-01-01

Methods for evaluating the impact of fires within tropical forests are needed as fires become more frequent and human populations and demands on forests increase. Short- and long-term fire effects on soils are determined by the prefire, fire, and postfire environments. We placed these components within a fire-disturbance continuum to guide our literature synthesis and...

The ecology of mixed severity fire regimes in Washington, Oregon, and Northern California

Treesearch

David Perry; Paul Hessburg; Carl Skinner; Thomas Spies; Scott Stephens; Alan Henry Taylor; Jerry Franklin; Brenda McComb; Greg Riegel

2011-01-01

Forests characterized by mixed-severity fires occupy a broad moisture gradient between lower elevation forests typified by low-severity fires and higher elevation forests in which high-severity, stand replacing fires are the norm. Mixed-severity forest types are poorly documented and little understood but likely occupy significant areas in the western United States. By...

Long-term impacts of prescribed fire on stand structure, growth, mortality, and individual tree vigor in Pinus resinosa forests

Treesearch

Sawyer S. Scherer; Anthony W. D' Amato; Christel C. Kern; Brian J. Palik; Matthew B. Russell

2016-01-01

Prescribed fire is increasingly being viewed as a valuable tool for mitigating the ecological consequences of long-term fire suppression within fire-adapted forest ecosystems. While the use of burning treatments in northern temperate conifer forests has at times received considerable attention, the long-term (>10 years) effects on forest structure and...

Forest health in the Blue Mountains: a management strategy for fire-adapted ecosystems.

Treesearch

R.W. Mutch; S.F. Arno; J.K. Brown; C.E. Carlson; R.D. Ottmar; J.L. Peterson

1993-01-01

The fire-adapted forests of the Blue Mountains are suffering from a forest health problem of catastrophic proportions. Contributing to the decline of forest health are such factors as the extensive harvesting of the western larch and ponderosa pine overstory during the 1900s, attempted exclusion of fire from a fire-dependent ecosystem, and the continuing drought. The...

Climatic stress increases forest fire severity across the western United States

USGS Publications Warehouse

van Mantgem, Philip J.; Nesmith, Jonathan C. B.; Keifer, MaryBeth; Knapp, Eric E.; Flint, Alan; Flint, Lorraine

2013-01-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after accounting for fire defences and injuries, and appeared to influence the effects of crown and stem injuries. Climate and fire interactions did not vary substantially across geographical regions, major genera and tree sizes. Our findings support recent physiological evidence showing that both drought and heating from fire can impair xylem conductivity. Warming trends have been linked to increasing probabilities of severe fire weather and fire spread; our results suggest that warming may also increase forest fire severity (the number of trees killed) independent of fire intensity (the amount of heat released during a fire).

Decadal time-scale monitoring of forest fires in Similipal Biosphere Reserve, India using remote sensing and GIS.

PubMed

Saranya, K R L; Reddy, C Sudhakar; Rao, P V V Prasada; Jha, C S

2014-05-01

Analyzing the spatial extent and distribution of forest fires is essential for sustainable forest resource management. There is no comprehensive data existing on forest fires on a regular basis in Biosphere Reserves of India. The present work have been carried out to locate and estimate the spatial extent of forest burnt areas using Resourcesat-1 data and fire frequency covering decadal fire events (2004-2013) in Similipal Biosphere Reserve. The anomalous quantity of forest burnt area was recorded during 2009 as 1,014.7 km(2). There was inconsistency in the fire susceptibility across the different vegetation types. The spatial analysis of burnt area shows that an area of 34.2 % of dry deciduous forests, followed by tree savannah, shrub savannah, and grasslands affected by fires in 2013. The analysis based on decadal time scale satellite data reveals that an area of 2,175.9 km(2) (59.6 % of total vegetation cover) has been affected by varied rate of frequency of forest fires. Fire density pattern indicates low count of burnt area patches in 2013 estimated at 1,017 and high count at 1,916 in 2004. An estimate of fire risk area over a decade identifies 12.2 km(2) is experiencing an annual fire damage. Summing the fire frequency data across the grids (each 1 km(2)) indicates 1,211 (26 %) grids are having very high disturbance regimes due to repeated fires in all the 10 years, followed by 711 grids in 9 years and 418 in 8 years and 382 in 7 years. The spatial database offers excellent opportunities to understand the ecological impact of fires on biodiversity and is helpful in formulating conservation action plans.

Climate change and forest fires.

PubMed

Flannigan, M D; Stocks, B J; Wotton, B M

2000-11-15

This paper addresses the impacts of climate change on forest fires and describes how this, in turn, will impact on the forests of the United States. In addition to reviewing existing studies on climate change and forest fires we have used two transient general circulation models (GCMs), namely the Hadley Centre and the Canadian GCMs, to estimate fire season severity in the middle of the next century. Ratios of 2 x CO2 seasonal severity rating (SSR) over present day SSR were calculated for the means and maximums for North America. The results suggest that the SSR will increase by 10-50% over most of North America; although, there are regions of little change or where the SSR may decrease by the middle of the next century. Increased SSRs should translate into increased forest fire activity. Thus, forest fires could be viewed as an agent of change for US forests as the fire regime will respond rapidly to climate warming. This change in the fire regime has the potential to overshadow the direct effects of climate change on species distribution and migration.

Wildfire and drought dynamics destabilize carbon stores of fire-suppressed forests.

PubMed

Earles, J Mason; North, Malcolm P; Hurteau, Matthew D

2014-06-01

Widespread fire suppression and thinning have altered the structure and composition of many forests in the western United States, making them more susceptible to the synergy of large-scale drought and fire events. We examine how these changes affect carbon storage and stability compared to historic fire-adapted conditions. We modeled carbon dynamics under possible drought and fire conditions over a 300-year simulation period in two mixed-conifer conditions common in the western United States: (1) pine-dominated with an active fire regime and (2) fir-dominated, fire suppressed forests. Fir-dominated stands, with higher live- and dead-wood density, had much lower carbon stability as drought and fire frequency increased compared to pine-dominated forest. Carbon instability resulted from species (i.e., fir's greater susceptibility to drought and fire) and stand (i.e., high density of smaller trees) conditions that develop in the absence of active management. Our modeling suggests restoring historic species composition and active fire regimes can significantly increase carbon stability in fire-suppressed, mixed-conifer forests. Long-term management of forest carbon should consider the relative resilience of stand structure and composition to possible increases in disturbance frequency and intensity under changing climate.

Factors affecting collective action for forest fire management: a comparative study of community forest user groups in central Siwalik, Nepal.

PubMed

Sapkota, Lok Mani; Shrestha, Rajendra Prasad; Jourdain, Damien; Shivakoti, Ganesh P

2015-01-01

The attributes of social ecological systems affect the management of commons. Strengthening and enhancing social capital and the enforcement of rules and sanctions aid in the collective action of communities in forest fire management. Using a set of variables drawn from previous studies on the management of commons, we conducted a study across 20 community forest user groups in Central Siwalik, Nepal, by dividing the groups into two categories based on the type and level of their forest fire management response. Our study shows that the collective action in forest fire management is consistent with the collective actions in other community development activities. However, the effectiveness of collective action is primarily dependent on the complex interaction of various variables. We found that strong social capital, strong enforcement of rules and sanctions, and users' participation in crafting the rules were the major variables that strengthen collective action in forest fire management. Conversely, users' dependency on a daily wage and a lack of transparency were the variables that weaken collective action. In fire-prone forests such as the Siwalik, our results indicate that strengthening social capital and forming and enforcing forest fire management rules are important variables that encourage people to engage in collective action in fire management.

Ecological responses to el Niño-induced surface fires in central Brazilian Amazonia: management implications for flammable tropical forests.

PubMed Central

Barlow, Jos; Peres, Carlos A

2004-01-01

Over the past 20 years the combined effects of El Niño-induced droughts and land-use change have dramatically increased the frequency of fire in humid tropical forests. Despite the potential for rapid ecosystem alteration and the current prevalence of wildfire disturbance, the consequences of such fires for tropical forest biodiversity remain poorly understood. We provide a pan-tropical review of the current state of knowledge of these fires, and include data from a study in a seasonally dry terra firme forest of central Brazilian Amazonia. Overall, this study supports predictions that rates of tree mortality and changes in forest structure are strongly linked to burn severity. The potential consequences for biomass loss and carbon emissions are explored. Despite the paucity of data on faunal responses to tropical forest fires, some trends are becoming apparent; for example, large canopy frugivores and understorey insectivorous birds appear to be highly sensitive to changes in forest structure and composition during the first 3 years after fires. Finally, we appraise the management implications of fires and evaluate the viability of techniques and legislation that can be used to reduce forest flammability, prevent anthropogenic ignition sources from coming into contact with flammable forests and aid the post-fire recovery process. PMID:15212091

Fire, climate change, and forest resilience in interior Alaska

Treesearch

Jill F. Johnstone; F. Stuart Chapin; Teresa N. Hollingsworth; Michelle C. Mack; Vladimir Romanovsky; Merritt Turetsky

2010-01-01

In the boreal forests of interior Alaska, feedbacks that link forest soils, fire characteristics, and plant traits have supported stable cycles of forest succession for the past 6000 years. This high resilience of forest stands to fire disturbance is supported by two interrelated feedback cycles: (i) interactions among disturbance regime and plant-soil-microbial...

The impact of anthropogenic climate change on wildfire across western US forests

NASA Astrophysics Data System (ADS)

Williams, P.; Abatzoglou, J. T.

2016-12-01

Increased forest fire activity across the western United States (US) in recent decades has contributed to widespread forest mortality, carbon emissions, periods of degraded air quality, and substantial fire suppression expenditures. The increase in forest fire activity has likely been enabled by a number of factors including the legacy of fire suppression and human settlement, changes in suppression policies, natural climate variability, and human-caused climate change. We use modeled climate projections to estimate the contribution of anthropogenic climate change to observed increases in eight fuel aridity metrics and forest fire area across the western US. Anthropogenic increases in temperature and vapor pressure deficit have significantly enhanced fuel aridity across western US forests over the past several decades. Comparing observational climate records to records recalculated after removal of modeled anthropogenic trends, we find that anthropogenic climate change accounted for approximately 55% of observed increases in the eight-metric mean fuel aridity during 1979-2015 across western US forests. This implicates anthropogenic climate change as an important driver of observed increases in fuel aridity, and also highlights the importance of natural multi-decadal climate variability in influencing trends in forest fire potential on the timescales of human lives. Based on a very strong (R2 = 0.76) and mechanistically reasonable relationship between interannual variability in the eight-metric mean fuel aridity and forest-fire area in the western US, we estimate that anthropogenic increases in fuel aridity contributed to an additional 4.2 million ha (95% confidence range: 2.7-6.5 million ha) of forest fire area during 1984-2015, nearly doubling the total forest fire area expected in the absence of anthropogenic climate change. The relationship between annual forest fire area and fuel aridity is exponential and the proportion of total forest area burned in a given year has grown rapidly over the past 32 years. Natural climate variability will continue to alternate between modulating and compounding anthropogenic increases in fuel aridity, but anthropogenic climate change has emerged as a chronic driver of increased forest fire activity and should continue to do so where fuels are not limiting.

Fire Impact on Surface Fuels and Carbon Emissions in Scots pine Logged Sites of Siberia

NASA Astrophysics Data System (ADS)

Ivanova, G. A.; Kukavskaya, E. A.; Bogorodskaya, A. V.; Ivanov, V. A.; Zhila, S. V.; Conard, S. G.

2012-04-01

Forest fire and large-scale forest harvesting are the two major disturbances in the Russian boreal forests. Non-recovered logged sites total about a million hectares. Logged sites are characterized by higher fire hazard than forest sites due great amounts of logging slash, which dries out much more rapidly compared to understory fuels. Moreover, most logging sites can be easily accessed by local population. Both legal and illegal logging are also increasing rapidly in many forest areas of Siberia. Fire effects on forest overstory, subcanopy woody layer, and ground vegetation biomass were estimated on logged vs. unlogged sites in the Central Siberia region in 2009-2012 as a part of the project "The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia" supported by NASA (NEESPI). Dead down woody fuels are significantly less at unburned/logged area of dry southern regions compared to more humid northern regions. Fuel consumption was typically less in spring fires than during summer fires. Fire-caused carbon emissions on logged sites appeared to be twice that on unlogged sites. Soil respiration is less at logged areas compared to undisturbed forest. After fire soil respiration decreases both at logged and unlogged areas. arbon emissions from fire and post-fire ecosystem damage on logged sites are expected to increase under changing climate conditions and as a result of anticipated increases in future forest harvesting in Siberia.

The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants.

PubMed

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-12-01

The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11-12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides as well as (40)K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in the oil shale combustion products. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of emerald ash borer on forests within the Huron River watershed of southeast Michigan

Treesearch

Annemarie Smith; Daniel A. Herms; Robert P. Long

2007-01-01

Emerald ash borer (Agrilus planipennis Fairmaire) (EAB), a buprestid beetle native to Asia, has killed millions of ash trees (Fraxinus spp.) over thousands of square miles in southeast Michigan, northwest Ohio and neighboring Ontario. This invasive pest has the potential to decimate ash across North America with major impacts on...

HOW to Identify and Manage Ash Yellows in Forest Stands and Home Landscapes

Treesearch

Steven Katovich; Wayne A. Sinclair

1994-01-01

Ash yellows is a recently discovered disease that causes slow growth and decline of ash (Fraxinus) species. Ash yellows went undetected until the 1980's because its symptoms were not differentiated from those of decline caused by adverse environmental factors such as drought, shallow soils, flooding, or parasitism by opportunistic fungi. Current knowledge supports...

78 FR 18629 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-27

... ash discharges after BADGER's 2014 operating system, perform other injunctive relief, and pay a $25... with the defendant's discharge of ash from BADGER, a coal- fired, stream-driven ferry that operates...

Climatic stress increases forest fire severity across the western United States

Treesearch

Phillip J. van Mantgem; Jonathan C.B. Nesmith; MaryBeth Keifer; Eric E. Knapp; Alan Flint; Lorriane Flint

2013-01-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after...

Contrasting spatial patterns in active-fire and fire-suppressed Mediterranean climate old-growth mixed conifer forests

Treesearch

Danny L. Fry; Scott L. Stephens; Brandon M. Collins; Malcolm North; Ernesto Franco-Vizcaino; Samantha J. Gill

2014-01-01

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference...

Reintroducing fire in regenerated dry forests following stand-replacing wildfire.

Treesearch

David W. Peterson; Paul F. Hessburg; Brion Salter; Kevin M. James; Matthew C. Dahlgreen; John A. Barnes

2007-01-01

Prescribed fire use may be effective for increasing fire resilience in young coniferous forests by reducing surface fuels, modifying overstory stand structure, and promoting development of large trees of fire resistant species. Questions remain, however, about when and how to reintroduce fire in regenerated forests, and to what end. We studied the effects of spring...

Lessons learned from prescribed fire in ponderosa pine forests of the southern Sierra Nevada

Treesearch

Karen E. Bagne; Kathryn L. Purcell

2009-01-01

Prescribed fire is a commonly used management tool in fire-suppressed ponderosa pine (Pinus ponderosa) forests, but effects of these fires on birds are largely unstudied. We investigated both direct and indirect impacts on breeding birds in ponderosa pine forests of the southern Sierra Nevada where fires were applied in the spring. Following...

Detection, Emission Estimation and Risk Prediction of Forest Fires in China Using Satellite Sensors and Simulation Models in the Past Three Decades—An Overview

PubMed Central

Zhang, Jia-Hua; Yao, Feng-Mei; Liu, Cheng; Yang, Li-Min; Boken, Vijendra K.

2011-01-01

Forest fires have major impact on ecosystems and greatly impact the amount of greenhouse gases and aerosols in the atmosphere. This paper presents an overview in the forest fire detection, emission estimation, and fire risk prediction in China using satellite imagery, climate data, and various simulation models over the past three decades. Since the 1980s, remotely-sensed data acquired by many satellites, such as NOAA/AVHRR, FY-series, MODIS, CBERS, and ENVISAT, have been widely utilized for detecting forest fire hot spots and burned areas in China. Some developed algorithms have been utilized for detecting the forest fire hot spots at a sub-pixel level. With respect to modeling the forest burning emission, a remote sensing data-driven Net Primary productivity (NPP) estimation model was developed for estimating forest biomass and fuel. In order to improve the forest fire risk modeling in China, real-time meteorological data, such as surface temperature, relative humidity, wind speed and direction, have been used as the model input for improving prediction of forest fire occurrence and its behavior. Shortwave infrared (SWIR) and near infrared (NIR) channels of satellite sensors have been employed for detecting live fuel moisture content (FMC), and the Normalized Difference Water Index (NDWI) was used for evaluating the forest vegetation condition and its moisture status. PMID:21909297

Detection, emission estimation and risk prediction of forest fires in China using satellite sensors and simulation models in the past three decades--an overview.

PubMed

Zhang, Jia-Hua; Yao, Feng-Mei; Liu, Cheng; Yang, Li-Min; Boken, Vijendra K

2011-08-01

Forest fires have major impact on ecosystems and greatly impact the amount of greenhouse gases and aerosols in the atmosphere. This paper presents an overview in the forest fire detection, emission estimation, and fire risk prediction in China using satellite imagery, climate data, and various simulation models over the past three decades. Since the 1980s, remotely-sensed data acquired by many satellites, such as NOAA/AVHRR, FY-series, MODIS, CBERS, and ENVISAT, have been widely utilized for detecting forest fire hot spots and burned areas in China. Some developed algorithms have been utilized for detecting the forest fire hot spots at a sub-pixel level. With respect to modeling the forest burning emission, a remote sensing data-driven Net Primary productivity (NPP) estimation model was developed for estimating forest biomass and fuel. In order to improve the forest fire risk modeling in China, real-time meteorological data, such as surface temperature, relative humidity, wind speed and direction, have been used as the model input for improving prediction of forest fire occurrence and its behavior. Shortwave infrared (SWIR) and near infrared (NIR) channels of satellite sensors have been employed for detecting live fuel moisture content (FMC), and the Normalized Difference Water Index (NDWI) was used for evaluating the forest vegetation condition and its moisture status.

75 FR 3193 - Information Collection; Annual Wildfire Summary Report

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-20

... addressed to Tim Melchert, Fire and Aviation Management, National Interagency Fire Center, Forest Service... Forest Service State and Private Forestry Cooperative Fire Program. The program provides supplemental funding for State and local fire fighting agencies. The Forest Service works cooperatively with State and...

A regional assessment of emerald ash borer impacts in the Eastern United States: ash mortality and abundance trends in time and space

Treesearch

Randall S. Morin; Scott A. Pugh; Andrew M. Liebhold; Susan J. Crocker

2015-01-01

The nonnative insect, emerald ash borer (Agrilus plannipennis Fairmaire), has caused extensive mortality of ash tree species (Fraxinus spp.) in the eastern United States. As of 2012, the pest had been detected in about 15 percent of the counties in the 37 states that comprise the natural range of ash in forests of the eastern...

Impact of the extreme 2009 wildfire Victoria the wettability of naturally highly water repellent soils

NASA Astrophysics Data System (ADS)

Doerr, Stefan H.; Shakesby, Richard A.; Sheridan, Gary J.; Lane, Patrick Nj; Smith, Hugh G.; Bell, Tina; Blake, William H.

2010-05-01

The recent catastrophic wildfires near Melbourne, which peaked on Feb. 7 2009, burned ca 400,000 ha and caused the tragic loss of 173 people. They occurred during unprecedented extreme fire weather where dry northerly winds gusting up to 100 km/h coincided with the highest temperatures ever recorded in this region. These conditions, combined with the very high biomass of mature eucalypt forests, very low fuel moisture conditions and steep slopes, generated extreme burning conditions. A rapid response project was launched under the NERC Urgency Scheme aimed at determining the effects of this extreme event on soil properties. Three replicate sites each were sampled for extremely high burn severity, high burn severity and unburnt control terrain, within mature mixed-species eucalypt forests near Marysville in April 2009. Ash and surface soil (0-2.5 cm and 2.5-5 cm) were collected at 20 sample grid points at each site. Here we report on outcomes from Water Drop Penetration Time (WDPT) tests carried out on soil samples to determine the impact of this extreme event on the wettability of a naturally highly water repellent soil. Field assessment suggested that the impact of this extreme wildfire on the soil was less than might be supposed given the extreme burn severity (indicated by the complete elimination of the ground vegetation). This was confirmed by the laboratory results. No major difference in WDPT was detected between (i) burned and control samples, and (ii) between surface and subsurface WDPT patterns, indicating that soil temperatures in the top 0-2.5 cm did not exceed ~200° C. Seedling germination in burned soil was reduced by at least 2/3 compared to the control samples, however, this reduction is indicative an only modest heat input into the soil. The limited heat input into the soil stands in stark contrast to the extreme burn severity (based on vegetation destruction parameters). We speculate that limited soil heating resulted perhaps from the unusually fast-moving fire front and the resultant short fire residence time during this event. Thick ash layers were present at the time of sampling despite some significant earlier pre-sampling rainfall events. This suggests that the wettable ash (up to 15 cm thick) was able to store substantial amounts of water, which would otherwise have formed overland flow moving over the highly water repellent underlying mineral soil. Once this hydrological ‘sponge' is removed, the lack of ground cover is expected to lead to the underlying soil being susceptible to erosion until the ground cover becomes re-established. This ‘erosion window‘ is likely to be relatively brief over much of the burnt area as the vegetation is already showing a comparatively rapid regrowth response. This is supported by initial results from laboratory germination experiments, which showed seedling emergence from even the most severely burnt sites. The factors contributing to the fire impacts determined here are explored in conjunction with predictions for future burn severity under a changing climate. The soil samples collected represent a reference soil sample collection, which are available to the scientific community for further investigation.

Factors that influence emerald ash borer (Agrilus planipennis) adult longevity and oviposition under laboratory conditions

Treesearch

Melody A. Keena; Juli Gould; Leah S. Bauer

2009-01-01

The emerald ash borer (EAB), Agrilus planipennis, is a nonnative insect from Asia that threatens ash trees in the urban and natural forests of North America. Research on this invasive insect and rearing parasitoids for...

Economic vulnerability of timber resources to forest fires.

PubMed

y Silva, Francisco Rodríguez; Molina, Juan Ramón; González-Cabán, Armando; Machuca, Miguel Ángel Herrera

2012-06-15

The temporal-spatial planning of activities for a territorial fire management program requires knowing the value of forest ecosystems. In this paper we extend to and apply the economic valuation principle to the concept of economic vulnerability and present a methodology for the economic valuation of the forest production ecosystems. The forest vulnerability is analyzed from criteria intrinsically associated to the forest characterization, and to the potential behavior of surface fires. Integrating a mapping process of fire potential and analytical valuation algorithms facilitates the implementation of fire prevention planning. The availability of cartography of economic vulnerability of the forest ecosystems is fundamental for budget optimization, and to help in the decision making process. Published by Elsevier Ltd.

Multi-season climate synchronized forest fires throughout the 20th century, Northern Rockies, USA

Treesearch

Penelope Morgan; Emily K. Heyerdahl; Carly E. Gibson

2008-01-01

We inferred climate drivers of 20th-century years with regionally synchronous forest fires in the U.S. northern Rockies. We derived annual fire extent from an existing fire atlas that includes 5038 fire polygons recorded from 12 070 086 ha, or 71% of the forested land in Idaho and Montana west of the Continental Divide. The 11 regional-fire years, those exceeding the...

Increasing resiliency in frequent fire forests: Lessons from the Sierra Nevada and western Australia

Treesearch

Scott L. Stephens

2014-01-01

This paper will primarily focus on the management and restoration of forests adapted to frequent, low-moderate intensity fire regimes. These are the forest types that are most at risk from large, high-severity wildfires and in many regions their fire regimes are changing. Fire as a landscape process can exhibit self-limiting characteristics in some forests which can...

Average stand age from forest inventory plots does not describe historical fire regimes in ponderosa pine and mixed-conifer forests of western North America

Treesearch

Jens T. Stevens; Hugh D. Safford; Malcolm P. North; Jeremy S. Fried; Andrew N. Gray; Peter M. Brown; Christopher R. Dolanc; Solomon Z. Dobrowski; Donald A. Falk; Calvin A. Farris; Jerry F. Franklin; Peter Z. Fulé; R. Keala Hagmann; Eric E. Knapp; Jay D. Miller; Douglas F. Smith; Thomas W. Swetnam; Alan H. Taylor; Julia A. Jones

2016-01-01

Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests...

Dry forests and wildland fires of the inland Northwest USA: contrasting the landscape ecology of the pre-settlement and modern eras.

Treesearch

Paul F. Hessburg; James K. Agee; Jerry F. Franklin

2005-01-01

Prior to Euro-American settlement, dry ponderosa pine and mixed conifer forests (hereafter, the "dry forests") of the Inland Northwest were burned by frequent low- or mixed-severity fires. These mostly surface fires maintained low and variable tree densities, light and patchy ground fuels, simplified forest structure, and favored fire-tolerant trees, such as...

Simulating boreal forest carbon dynamics after stand-replacing fire disturbance: insights from a global process-based vegetation model

NASA Astrophysics Data System (ADS)

Yue, C.; Ciais, P.; Luyssaert, S.; Cadule, P.; Harden, J.; Randerson, J.; Bellassen, V.; Wang, T.; Piao, S. L.; Poulter, B.; Viovy, N.

2013-04-01

Stand-replacing fires are the dominant fire type in North American boreal forest and leave a historical legacy of a mosaic landscape of different aged forest cohorts. To accurately quantify the role of fire in historical and current regional forest carbon balance using models, one needs to explicitly simulate the new forest cohort that is established after fire. The present study adapted the global process-based vegetation model ORCHIDEE to simulate boreal forest fire CO2 emissions and follow-up recovery after a stand-replacing fire, with representation of postfire new cohort establishment, forest stand structure and the following self-thinning process. Simulation results are evaluated against three clusters of postfire forest chronosequence observations in Canada and Alaska. Evaluation variables for simulated postfire carbon dynamics include: fire carbon emissions, CO2 fluxes (gross primary production, total ecosystem respiration and net ecosystem exchange), leaf area index (LAI), and biometric measurements (aboveground biomass carbon, forest floor carbon, woody debris carbon, stand individual density, stand basal area, and mean diameter at breast height). The model simulation results, when forced by local climate and the atmospheric CO2 history on each chronosequence site, generally match the observed CO2 fluxes and carbon stock data well, with model-measurement mean square root of deviation comparable with measurement accuracy (for CO2 flux ~100 g C m-2 yr-1, for biomass carbon ~1000 g C m-2 and for soil carbon ~2000 g C m-2). We find that current postfire forest carbon sink on evaluation sites observed by chronosequence methods is mainly driven by historical atmospheric CO2 increase when forests recover from fire disturbance. Historical climate generally exerts a negative effect, probably due to increasing water stress caused by significant temperature increase without sufficient increase in precipitation. Our simulation results demonstrate that a global vegetation model such as ORCHIDEE is able to capture the essential ecosystem processes in fire-disturbed boreal forests and produces satisfactory results in terms of both carbon fluxes and carbon stocks evolution after fire, making it suitable for regional simulations in boreal regions where fire regimes play a key role on ecosystem carbon balance.

Forest structure and fire hazard in dry forests of the Western United States

Treesearch

David L. Peterson; Morris C. Johnson; James K. Agee; Theresa B. Jain; Donald McKenzie; Elizabeth D. Reinhardt

2005-01-01

Fire, in conjunction with landforms and climate, shapes the structure and function of forests throughout the Western United States, where millions of acres of forest lands contain accumulations of flammable fuel that are much higher than historical conditions owing to various forms of fire exclusion. The Healthy Forests Restoration Act mandates that public land...

Population dynamics of an invasive forest insect and associated natural enemies in the aftermath of invasion: implications for biological control

Treesearch

Jian J. Duan; Leah S. Bauer; Kristopher J. Abell; Michael D. Ulyshen; Roy G. Van Driesche

2015-01-01

1. Understanding the population dynamics of exotic pests and associated natural enemies is important in developing sound management strategies in invaded forest ecosystems. The emerald ash borer (EAB) Agrilus planipennis Fairmaire is an invasive phloem-feeding beetle that has killed tens of millions of ash Fraxinus trees in North...

Fire effects on temperate forest soil C and N storage.

PubMed

Nave, Lucas E; Vance, Eric D; Swanston, Christopher W; Curtis, Peter S

2011-06-01

Temperate forest soils store globally significant amounts of carbon (C) and nitrogen (N). Understanding how soil pools of these two elements change in response to disturbance and management is critical to maintaining ecosystem services such as forest productivity, greenhouse gas mitigation, and water resource protection. Fire is one of the principal disturbances acting on forest soil C and N storage and is also the subject of enormous management efforts. In the present article, we use meta-analysis to quantify fire effects on temperate forest soil C and N storage. Across a combined total of 468 soil C and N response ratios from 57 publications (concentrations and pool sizes), fire had significant overall effects on soil C (-26%) and soil N (-22%). The impacts of fire on forest floors were significantly different from its effects on mineral soils. Fires reduced forest floor C and N storage (pool sizes only) by an average of 59% and 50%, respectively, but the concentrations of these two elements did not change. Prescribed fires caused smaller reductions in forest floor C and N storage (-46% and -35%) than wildfires (-67% and -69%), and the presence of hardwoods also mitigated fire impacts. Burned forest floors recovered their C and N pools in an average of 128 and 103 years, respectively. Among mineral soils, there were no significant changes in C or N storage, but C and N concentrations declined significantly (-11% and -12%, respectively). Mineral soil C and N concentrations were significantly affected by fire type, with no change following prescribed burns, but significant reductions in response to wildfires. Geographic variation in fire effects on mineral soil C and N storage underscores the need for region-specific fire management plans, and the role of fire type in mediating C and N shifts (especially in the forest floor) indicates that averting wildfires through prescribed burning is desirable from a soils perspective.

Speciation of arsenic, selenium, and chromium in wildfire impacted soils and ashes

USGS Publications Warehouse

Wolf, Ruth E.; Hoefen, Todd M.; Hageman, Philip L.; Morman, Suzette A.; Plumlee, Geoffrey S.

2010-01-01

In 2007-09, California experienced several large wildfires that damaged large areas of forest and destroyed many homes and buildings. The U.S. Geological Survey collected samples from the Harris, Witch, Grass Valley, Ammo, Santiago, Canyon, Jesusita, and Station fires for testing to identify any possible characteristics of the ashes and soils from burned areas that may be of concern for their impact on water quality, human health, and endangered species. The samples were subjected to analysis for bulk chemical composition for 44 elements by inductively coupled plasma mass spectrometry (ICP-MS) after acid digestion and de-ionized water leach tests for pH, alkalinity, conductivity, and anions. Water leach tests generated solutions ranging from pH 10-12, suggesting that ashes can generate caustic alkalinity in contact with rainwater or body fluids (for example, sweat and fluids in the respiratory tract). Samples from burned residential areas in the 2007 fires had elevated levels for several metals, including: As, Pb, Sb, Cu, Zn, and Cr. In some cases, the levels found were above the U.S. Environmental Protection Agency (USEPA) preliminary remediation goals (PRG) for soils. Speciation analyses were conducted on de-ionized water and simulated lung fluid leachates for As(III), As(V), Se(IV), Se(VI), Cr(III), and Cr(VI). All species were determined in the same analytical run using an ion-pairing HPLC-ICP-MS method. For leachates containing high levels of total Cr, the majority of the chromium was present in the hexavalent, Cr(VI), form. Higher total and hexavalent chromium levels were observed for samples collected from burned residential areas. Arsenic was also generally present in the more oxidized, As(V), form. Selenium (IV) and (VI) were present, but typically at levels below 2 ppb for most samples. Stability studies of leachate solutions under different storage conditions were performed and the suitability of different sample preservation methods for speciation analysis will be discussed.

Prospects for the development of coal-steam plants in Russia

NASA Astrophysics Data System (ADS)

Tumanovskii, A. G.

2017-06-01

Evaluation of the technical state of the modern coal-fired power plants and quality of coal consumed by Russian thermal power plants (TPP) is provided. Measures aimed at improving the economic and environmental performance of operating 150-800 MW coal power units are considered. Ways of efficient use of technical methods of NO x control and electrostatic precipitators' upgrade for improving the efficiency of ash trapping are summarized. Examples of turbine and boiler equipment efficiency upgrading through its deep modernization are presented. The necessity of the development and introduction of new technologies in the coal-fired power industry is shown. Basic technical requirements for a 660-800 MW power unit with the steam conditions of 28 MPa, 600/600°C are listed. Design solutions taking into account features of Russian coal combustion are considered. A field of application of circulating fluidized bed (CFB) boilers and their effectiveness are indicated. The results of development of a new generation coal-fired TPP, including a steam turbine with an increased efficiency of the compartments and disengaging clutch, an elevated steam conditions boiler, and a highly efficient NO x /SO2 and ash particles emission control system are provided. In this case, the resulting ash and slag are not to be sent to the ash dumps and are to be used to a maximum advantage. Technical solutions to improve the efficiency of coal gasification combined cycle plants (CCP) are considered. A trial plant based on a 16 MW gas turbine plant (GTP) and an air-blown gasifier is designed as a prototype of a high-power CCP. The necessity of a state-supported technical reequipment and development program of operating coal-fired power units, as well as putting into production of new generation coal-fired power plants, is noted.

WebGIS Platform Adressed to Forest Fire Management Methodologies

NASA Astrophysics Data System (ADS)

André Ramos-Simões, Nuno; Neto Paixão, Helena Maria; Granja Martins, Fernando Miguel; Pedras, Celestina; Lança, Rui; Silva, Elisa; Jordán, António; Zavala, Lorena; Soares, Cristina

2015-04-01

Forest fires are one of the natural disasters that causes more damages in nature, as well as high material costs, and sometimes, a significant losses in human lives. In summer season, when high temperatures are attained, fire may rapidly progress and destroy vast areas of forest and also rural and urban areas. The forest fires have effect on forest species, forest composition and structure, soil properties and soil capacity for nutrient retention. In order to minimize the negative impact of the forest fires in the environment, many studies have been developed, e.g. Jordán et al (2009), Cerdà & Jordán (2010), and Gonçalves & Vieira (2013). Nowadays, Remote Sensing (RS) and Geographic Information System (GIS) technologies are used as support tools in fire management decisions, namely during the fire, but also before and after. This study presents the development of a user-friendly WebGIS dedicated to share data, maps and provide updated information on forest fire management for stakeholders in Iberia Peninsula. The WebGIS platform was developed with ArcGIS Online, ArcGIS for Desktop; HyperText Markup Language (HTML) and Javascript. This platform has a database that includes spatial and alphanumeric information, such as: origin, burned areas, vegetation change over time, terrain natural slope, land use, soil erosion and fire related hazards. The same database contains also the following relevant information: water sources, forest tracks and traffic ways, lookout posts and urban areas. The aim of this study is to provide the authorities with a tool to assess risk areas and manage more efficiently forest fire hazards, giving more support to their decisions and helping the populations when facing this kind of phenomena.

Forest fire laboratory at Riverside and fire research in California: past, present, and future

Treesearch

Carl C. Wilson; James B. Davis

1988-01-01

The need for protection from uncontrolled fire in California was identified by Abbott Kinney, Chairman of the State Board of Forestry, more than 75 years before the construction of the Riverside Forest Fire Laboratory. With the organization of the USDA Forest Service the need for an effective fire protection organization became apparent. In response, a...

The Missoula Fire Sciences Laboratory: A 50-year dedication to understanding wildlands and fire

Treesearch

Diane M. Smith

2012-01-01

In 1960, the USDA Forest Service established the Northern Forest Fire Laboratory (now the Missoula Fire Sciences Laboratory) to find scientific solutions for better managing the nation's wildland resources and to research ways to improve forest fire prevention and suppression. This new state-of-the-art research facility did not emerge from a vacuum, however. This...

Modeling of multi-strata forest fire severity using Landsat TM data

Treesearch

Q. Meng; R.K. Meentemeyer

2011-01-01

Most of fire severity studies use field measures of composite burn index (CBI) to represent forest fire severity and fit the relationships between CBI and Landsat imagery derived differenced normalized burn ratio (dNBR) to predict and map fire severity at unsampled locations. However, less attention has been paid on the multi-strata forest fire severity, which...

Lightning fires in southwestern forests

Treesearch

Jack S. Barrows

1978-01-01

Lightning is the leading cause of fires in southwestern forests. On all protected private, state and federal lands in Arizona and New Mexico, nearly 80 percent of the forest, brush and range fires are ignited by lightning. The Southwestern region leads all other regions of the United States both in total number of lightning fires and in the area burned by these fires...

1954 forest fire weather in western Oregon and Washington.

Treesearch

Owen P. Cramer

1954-01-01

For the second successive fire season forest fire weather in western Oregon and Washington was far below normal severity. The low danger is reflected in record low numbers of fires reported by forestry offices of both States and by the U. S. Forest Service for their respective protection areas. Although spring and fall fire weather was near normal, a rain-producing...

Post-fire surface fuel dynamics in California forests across three burn severity classes

Treesearch

Bianca N. I. Eskelson; Vicente J. Monleon

2018-01-01

Forest wildfires consume fuel and are followed by post-fire fuel accumulation. This study examines post-fire surface fuel dynamics over 9 years across a wide range of conditions characteristic of California fires in dry conifer and hardwood forests. We estimated post-fire surface fuel loadings (Mg ha _1) from 191 repeatedly measured United States...

Forest Understory Fire in the Brazilian Amazon in ENSO and Non-ENSO Years: Area Burned and Committed Carbon Emissions

NASA Technical Reports Server (NTRS)

Alencar, A.; Nepstad, D.; Ver-Diaz, M. Del. C.

2004-01-01

"Understory fires" that burn the floor of standing forests are one of the most important types of forest impoverishment in the Amazon, especially during the severe droughts of El Nino Southern Oscillation (ENSO) episodes. However, we are aware of no estimates of the areal extent of these fires for the Brazilian Amazon and, hence, of their contribution to Amazon carbon fluxes to the atmosphere. We calculated the area of forest understory fires for the Brazilian Amazon region during an El Nino (1998) and a non El Nino (1995) year based on forest fire scars mapped with satellite images for three locations in eastern and southern Amazon, where deforestation is concentrated. The three study sites represented a gradient of both forest types and dry season severity. The burning scar maps were used to determine how the percentage of forest that burned varied with distance from agricultural clearings. These spatial functions were then applied to similar forest/climate combinations outside of the study sites to derive an initial estimate for the Brazilian Amazon. Ninety-one percent of the forest area that burned in the study sites was within the first kilometer of a clearing for the non ENSO year and within the first four kilometers for the ENSO year. The area of forest burned by understory forest fire during the severe drought (ENSO) year (3.9 millions of hectares) was 13 times greater than the area burned during the average rainfall year (0.2 million hectares), and twice the area of annual deforestation rate. Dense forest was, proportionally, the forest area most affected by understory fires during the El Nino year, while understory fires were concentrated in transitional forests during the year of average rainfall. Our estimate of aboveground tree biomass killed by fire ranged from 0.06 Pg to 0.38 Pg during the ENSO and from 0,004 Pg to 0,024 Pg during the non ENSO.

Synergy between land use and climate change increases future fire risk in Amazon forests

DOE PAGES

Le Page, Yannick; Morton, Douglas; Hartin, Corinne; ...

2017-12-20

Tropical forests have been a permanent feature of the Amazon basin for at least 55 million years, yet climate change and land use threaten the forest's future over the next century. Understory forest fires, which are common under the current climate in frontier forests, may accelerate Amazon forest losses from climate-driven dieback and deforestation. Far from land use frontiers, scarce fire ignitions and high moisture levels preclude significant burning, yet projected climate and land use changes may increase fire activity in these remote regions. Here, we used a fire model specifically parameterized for Amazon understory fires to examine the interactionsmore » between anthropogenic activities and climate under current and projected conditions. In a scenario of low mitigation efforts with substantial land use expansion and climate change – Representative Concentration Pathway (RCP) 8.5 – projected understory fires increase in frequency and duration, burning 4–28 times more forest in 2080–2100 than during 1990–2010. In contrast, active climate mitigation and land use contraction in RCP4.5 constrain the projected increase in fire activity to 0.9–5.4 times contemporary burned area. Importantly, if climate mitigation is not successful, land use contraction alone is very effective under low to moderate climate change, but does little to reduce fire activity under the most severe climate projections. These results underscore the potential for a fire-driven transformation of Amazon forests if recent regional policies for forest conservation are not paired with global efforts to mitigate climate change.« less

Forest Fire Danger Rating (FFDR) Prediction over the Korean Peninsula

NASA Astrophysics Data System (ADS)

Song, B.; Won, M.; Jang, K.; Yoon, S.; Lim, J.

2016-12-01

Approximately five hundred forest fires occur and inflict the losses of both life and property each year in Korea during the forest fire seasons in the spring and autumn. Thus, an accurate prediction of forest fire is essential for effective forest fire prevention. The meteorology is one of important factors to predict and understand the fire occurrence as well as its behaviors and spread. In this study, we present the Forest Fire Danger Rating Systems (FFDRS) on the Korean Peninsula based on the Daily Weather Index (DWI) which represents the meteorological characteristics related to forest fire. The thematic maps including temperature, humidity, and wind speed produced from Korea Meteorology Administration (KMA) were applied to the forest fire occurrence probability model by logistic regression to analyze the DWI over the Korean Peninsula. The regional data assimilation and prediction system (RDAPS) and the improved digital forecast model were used to verify the sensitivity of DWI. The result of verification test revealed that the improved digital forecast model dataset showed better agreements with the real-time weather data. The forest fire danger rating index (FFDRI) calculated by the improved digital forecast model dataset showed a good agreement with the real-time weather dataset at the 233 administrative districts (R2=0.854). In addition, FFDRI were compared with observation-based FFDRI at 76 national weather stations. The mean difference was 0.5 at the site-level. The results produced in this study indicate that the improved digital forecast model dataset can be useful to predict the FFDRI in the Korean Peninsula successfully.

Early recruitment responses to interactions between frequent fires, nutrients, and herbivory in the southern Amazon.

PubMed

Massad, Tara Joy; Balch, Jennifer K; Mews, Cândida Lahís; Porto, Pábio; Marimon Junior, Ben Hur; Quintino, Raimundo Mota; Brando, P M; Vieira, Simone A; Trumbore, Susan E

2015-07-01

Understanding tropical forest diversity is a long-standing challenge in ecology. With global change, it has become increasingly important to understand how anthropogenic and natural factors interact to determine diversity. Anthropogenic increases in fire frequency are among the global change variables affecting forest diversity and functioning, and seasonally dry forest of the southern Amazon is among the ecosystems most affected by such pressures. Studying how fire will impact forests in this region is therefore important for understanding ecosystem functioning and for designing effective conservation action. We report the results of an experiment in which we manipulated fire, nutrient availability, and herbivory. We measured the effects of these interacting factors on the regenerative capacity of the ecotone between humid Amazon forest and Brazilian savanna. Regeneration density, diversity, and community composition were severely altered by fire. Additions of P and N + P reduced losses of density and richness in the first year post-fire. Herbivory was most important just after germination. Diversity was positively correlated with herbivory in unburned forest, likely because fire reduced the number of reproductive individuals. This contrasts with earlier results from the same study system in which herbivory was related to increased diversity after fire. We documented a significant effect of fire frequency; diversity in triennially burned forest was more similar to that in unburned than in annually burned forest, and the community composition of triennially burned forest was intermediate between unburned and annually burned areas. Preventing frequent fires will therefore help reduce losses in diversity in the southern Amazon's matrix of human-altered landscapes.

Synergy between land use and climate change increases future fire risk in Amazon forests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Le Page, Yannick; Morton, Douglas; Hartin, Corinne

Tropical forests have been a permanent feature of the Amazon basin for at least 55 million years, yet climate change and land use threaten the forest's future over the next century. Understory forest fires, which are common under the current climate in frontier forests, may accelerate Amazon forest losses from climate-driven dieback and deforestation. Far from land use frontiers, scarce fire ignitions and high moisture levels preclude significant burning, yet projected climate and land use changes may increase fire activity in these remote regions. Here, we used a fire model specifically parameterized for Amazon understory fires to examine the interactionsmore » between anthropogenic activities and climate under current and projected conditions. In a scenario of low mitigation efforts with substantial land use expansion and climate change – Representative Concentration Pathway (RCP) 8.5 – projected understory fires increase in frequency and duration, burning 4–28 times more forest in 2080–2100 than during 1990–2010. In contrast, active climate mitigation and land use contraction in RCP4.5 constrain the projected increase in fire activity to 0.9–5.4 times contemporary burned area. Importantly, if climate mitigation is not successful, land use contraction alone is very effective under low to moderate climate change, but does little to reduce fire activity under the most severe climate projections. These results underscore the potential for a fire-driven transformation of Amazon forests if recent regional policies for forest conservation are not paired with global efforts to mitigate climate change.« less

Are High-Severity Fires Burning at Much Higher Rates Recently than Historically in Dry-Forest Landscapes of the Western USA?

PubMed Central

Baker, William L.

2015-01-01

Dry forests at low elevations in temperate-zone mountains are commonly hypothesized to be at risk of exceptional rates of severe fire from climatic change and land-use effects. Their setting is fire-prone, they have been altered by land-uses, and fire severity may be increasing. However, where fires were excluded, increased fire could also be hypothesized as restorative of historical fire. These competing hypotheses are not well tested, as reference data prior to widespread land-use expansion were insufficient. Moreover, fire-climate projections were lacking for these forests. Here, I used new reference data and records of high-severity fire from 1984–2012 across all dry forests (25.5 million ha) of the western USA to test these hypotheses. I also approximated projected effects of climatic change on high-severity fire in dry forests by applying existing projections. This analysis showed the rate of recent high-severity fire in dry forests is within the range of historical rates, or is too low, overall across dry forests and individually in 42 of 43 analysis regions. Significant upward trends were lacking overall from 1984–2012 for area burned and fraction burned at high severity. Upward trends in area burned at high severity were found in only 4 of 43 analysis regions. Projections for A.D. 2046–2065 showed high-severity fire would generally be still operating at, or have been restored to historical rates, although high projections suggest high-severity fire rotations that are too short could ensue in 6 of 43 regions. Programs to generally reduce fire severity in dry forests are not supported and have significant adverse ecological impacts, including reducing habitat for native species dependent on early-successional burned patches and decreasing landscape heterogeneity that confers resilience to climatic change. Some adverse ecological effects of high-severity fires are concerns. Managers and communities can improve our ability to live with high-severity fire in dry forests. PMID:26351850

Hayman Fire case study: Summary [RMRS-GTR-114

Treesearch

Russell T. Graham

2003-01-01

Historically, wildfires burned Western forests creating and maintaining a variety of forest compositions and structures (Agee 1993). Prior to European settlement lightning along with Native Americans ignited fires routinely across many forested landscapes. After Euro-American settlement, fires continued to be quite common with fires ignited by settlers, railroads, and...

36 CFR 211.4 - Cooperation for fire prevention and control.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Cooperation for fire... AGRICULTURE ADMINISTRATION Cooperation § 211.4 Cooperation for fire prevention and control. The Forest Service... will result in mutual benefit in the prevention and suppression of forest fires: Provided, That the...

36 CFR 211.4 - Cooperation for fire prevention and control.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Cooperation for fire... AGRICULTURE ADMINISTRATION Cooperation § 211.4 Cooperation for fire prevention and control. The Forest Service... will result in mutual benefit in the prevention and suppression of forest fires: Provided, That the...

Environmentally friendly use of non-coal ashes in Sweden.

PubMed

Ribbing, C

2007-01-01

The Swedish Thermal Engineering Research Institute (Värmeforsk) initiated an applied research program "Environmentally friendly use of non-coal ashes", in 2002. The program aims at increasing knowledge on the by-products of energy production and their application. The goal of formulating technical and environmental guidelines and assessments is a major point of the program, which is supported by about forty authorities and private organisations. The programme has been divided into four areas: recycling of ashes to forests, geotechnical applications, use in landfilling, and environmental aspects and chemistry. Among all results obtained, the following progress is shown: *Evidence for the positive effects of spreading ashes on forest growth. *A proposal for environmental guidelines on the utilisation of ashes in construction. *A handbook for using non-coal fly ashes in unpaved roads. *Technical and environmental assessments of MSWI bottom ashes in road construction. *Development of the use of ashes with municipal wastewater sludge as a cover for landfills and mine tailings. *Use of ashes from bio-fuels in concrete and replacement of cement in stoop mining. *A method to classify those by-products from combustion that have mirror entries in the EWC as a hazardous or non-hazardous compound. The Ash Programme has also made it possible to increase knowledge on ashes as valuable materials, on quality assurance and on markets for recovered materials.

Analysing Forst Fores in China

NASA Astrophysics Data System (ADS)

Casanova, Jose-Luis; Sanz, Julia; Garcia, Miguel; Salvador, Pablo; Quin, Xianlin; Li, Zengyuan; Yin, Lingyu; Sun, Guifen; Goldammer, Johann

2016-08-01

Forest fires are a major concern in China because of the economical and biodiversity looses and because the emission of trace gases into the atmosphere. During 12 years LATUV has been working in the development of forest fires products, especially in North China. A catalogue of products has been generated like: forest fire detection, burnt area mapping, gas emissions, severity and burnt biomass.Forest fires can be detected by different platforms and sensor but the rate of false alarms is high because of industrial activity. The gas emissions are important, because of the forest fires inside China and because the forest fires between China and Russia that have a considerable impact in the atmosphere composition in China.The availability of new sensors on board sentinel 2 and sentinel 3 platforms will increase the product catalogue with new products more accurate and increasing the periodicity information.

Long-term boreal forest dynamics and disturbances: a multi-proxy approach

NASA Astrophysics Data System (ADS)

Stivrins, Normunds; Aakala, Tuomas; Kuuluvainen, Timo; Pasanen, Leena; Ilvonen, Liisa; Holmström, Lasse; Seppä, Heikki

2017-04-01

The boreal forest provides a variety of ecosystem services that are threatened under the ongoing climate warming. Along with the climate, there are several factors (fire, human-impact, pathogens), which influence boreal forest dynamics. Combination of short and long-term studies allowing complex assessment of forest response to natural abiotic and biotic stress factors is necessary for sustainable management of the boreal forest now and in the future. The ongoing EBOR (Ecological history and long-term dynamics of the boreal forest ecosystem) project integrates forest ecological and palaeoecological approaches to study boreal forest dynamics and disturbances. Using pollen, non-pollen palynomorphs, micro- and macrocharcoal, tree rings and fire scars, we analysed forest dynamics at stand-scale by sampling small forest hollows (small paludified depressions) and the surrounding forest stands in Finland and western Russia. Using charcoal data, we estimated a fire return interval of 320 years for the Russian sites, and, based on the fungi Neurospora that can grow on charred tree bark after a low-intensity fire, we were able to distinguish low- and high-intensity fire-events. In addition to the influence of fire events and/or fire regime changes, we further assessed potential relationships between tree species and herbivore presence and pathogens. As an example of such a relationship, our preliminary findings indicated a negative relationship between Picea and fungi Lasiosphaeria (caudata), which occurred during times of Picea decline.

Contrasting spatial patterns in active-fire and fire-suppressed Mediterranean climate old-growth mixed conifer forests.

PubMed

Fry, Danny L; Stephens, Scott L; Collins, Brandon M; North, Malcolm P; Franco-Vizcaíno, Ernesto; Gill, Samantha J

2014-01-01

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha(-1), and occupied 27-46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11-20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥ 56%) in large patches (≥ 10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types.

Short-Term Responses of Ground Beetles to Forest Changes Caused by Early Stages of Emerald Ash Borer (Coleoptera: Buprestidae)-Induced Ash Mortality.

PubMed

Perry, Kayla I; Herms, Daniel A

2016-04-22

Emerald ash borer (Agrilus planipennis Fairmaire), an invasive wood-boring beetle native to Asia, has killed hundreds of millions of ash trees since its accidental introduction into North America, resulting in widespread formation of canopy gaps and accumulations of coarse woody debris (CWD) in forests. The objective was to quantify effects of canopy gaps and CWD caused by early stages of emerald ash borer-induced ash mortality, and their interaction on ground beetle assemblages. The impact of canopy gaps and CWD varied, as gaps affected beetle assemblages in 2011, while effects of CWD were only observed in 2012. Gaps decreased beetle activity-abundance, and marginally decreased richness, driving changes in species composition, but evenness and diversity were unaffected. Effects of the CWD treatment alone were minimal, but CWD interacted with the canopy treatment, resulting in an increase in activity-abundance of ground beetles in canopy gaps without CWD, and a marginal increase in species richness in canopy gaps with CWD. Although there were some initial changes in species composition, these were ephemeral, suggesting that ground beetle assemblages may be resilient to disturbance caused by emerald ash borer. This study contributes to our understanding of the cascading ecological impacts of biological invasions on forest ecosystems. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Assessment of Black Ash (Fraxinus nigra) Decline in Minnesota. Chapter 12

Treesearch

Brian J. Palik; Michael E. Ostry; Robert C. Venette; Kathleen T. Ward

2012-01-01

Black ash (Fraxinus nigra) is present throughout the upper Midwest and Northeastern United States and is often found in lowland hardwood forests. Black ash seed is an important food for birds and small mammals, and its twigs and foliage are used by ungulates. Black ash wood is valued for paneling and furniture as well as for Native American basketry...

Changes in ash tree demography associated with emerld ash borer invasion, indicated by regional forest inventory data from the Great Lakes States

Treesearch

Scott A. Pugh; Andrew M. Liebhold; Randall S. Morin

2011-01-01

The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) is a nonnative phloem-feeding beetle that was accidentally introduced near Detroit, Michigan, two to three decades ago. North American ash (Fraxinus spp.) exhibit little or no resistance, and as this insect species expands its range, extensive mortality results. Previous...

Natural enemies implicated in the regulation of an invasive pest: a life table analysis of the population dynamics of the emerald ash Borer

USDA-ARS?s Scientific Manuscript database

The emerald ash borer (EAB), Agrilus planipennis Fairmaire, is a serious invasive forest pest that has killed tens of millions of ash (Fraxinus) trees in the United States and Canada. By caging EAB adults on trunks of healthy ash trees, we established three generations of experimental cohorts from ...

Risk to ash from emerald ash borer: can biological control prevent the loss of ash stands?

Treesearch

Jian J. Duan; Roy G. Van Driesche; Leah S. Bauer; Daniel M. Kashian; Daniel A. Herms

2015-01-01

Ash trees (Fraxinus spp.) are an important components of both natural forests and urban plantings in the United States and Canada (Federal Register, 2003; Nowak et al., 2003). There are approximately 16 species of Fraxinus native to North America (Harlow et al., 1996; USGS, 2014), each adapted to different ecological niches across...

Outlook for ash in your forest: results of emerald ash borer research and implications for management

Treesearch

Kathleen S. Knight

2014-01-01

Since its accidental introduction near Detroit, Michigan, in the mid-1990s, emerald ash borer (EAB) has rapidly spread through much of the U.S. and adjacent Canada, leaving millions of dead ash trees in Midwestern states (4,11). Unfortunately, EAB attacks trees as small as an inch in stem diameter and it attacks all five ash species native to the region - white, green...

Impact of anthropogenic climate change on wildfire across western US forests.

PubMed

Abatzoglou, John T; Williams, A Park

2016-10-18

Increased forest fire activity across the western continental United States (US) in recent decades has likely been enabled by a number of factors, including the legacy of fire suppression and human settlement, natural climate variability, and human-caused climate change. We use modeled climate projections to estimate the contribution of anthropogenic climate change to observed increases in eight fuel aridity metrics and forest fire area across the western United States. Anthropogenic increases in temperature and vapor pressure deficit significantly enhanced fuel aridity across western US forests over the past several decades and, during 2000-2015, contributed to 75% more forested area experiencing high (>1 σ) fire-season fuel aridity and an average of nine additional days per year of high fire potential. Anthropogenic climate change accounted for ∼55% of observed increases in fuel aridity from 1979 to 2015 across western US forests, highlighting both anthropogenic climate change and natural climate variability as important contributors to increased wildfire potential in recent decades. We estimate that human-caused climate change contributed to an additional 4.2 million ha of forest fire area during 1984-2015, nearly doubling the forest fire area expected in its absence. Natural climate variability will continue to alternate between modulating and compounding anthropogenic increases in fuel aridity, but anthropogenic climate change has emerged as a driver of increased forest fire activity and should continue to do so while fuels are not limiting.

Impact of anthropogenic climate change on wildfire across western US forests

NASA Astrophysics Data System (ADS)

Abatzoglou, John T.; Park Williams, A.

2016-10-01

Increased forest fire activity across the western continental United States (US) in recent decades has likely been enabled by a number of factors, including the legacy of fire suppression and human settlement, natural climate variability, and human-caused climate change. We use modeled climate projections to estimate the contribution of anthropogenic climate change to observed increases in eight fuel aridity metrics and forest fire area across the western United States. Anthropogenic increases in temperature and vapor pressure deficit significantly enhanced fuel aridity across western US forests over the past several decades and, during 2000-2015, contributed to 75% more forested area experiencing high (>1 σ) fire-season fuel aridity and an average of nine additional days per year of high fire potential. Anthropogenic climate change accounted for ˜55% of observed increases in fuel aridity from 1979 to 2015 across western US forests, highlighting both anthropogenic climate change and natural climate variability as important contributors to increased wildfire potential in recent decades. We estimate that human-caused climate change contributed to an additional 4.2 million ha of forest fire area during 1984-2015, nearly doubling the forest fire area expected in its absence. Natural climate variability will continue to alternate between modulating and compounding anthropogenic increases in fuel aridity, but anthropogenic climate change has emerged as a driver of increased forest fire activity and should continue to do so while fuels are not limiting.

Long-term effects of fire and harvest on carbon stocks of boreal forests in northeastern China

NASA Astrophysics Data System (ADS)

Huang, C.; He, H. S.; Hawbaker, T. J.; Zhu, Z.; Liang, Y.; Gong, P.

2017-12-01

Fire, harvest and their interactions have strong effects on boreal forests carbon stocks. Repeated disturbances associated with relatively short fire return intervals and harvest rotations, and their interactions caused their effects to increase over simulation time.Boreal forests in the northeastern of China cover 8.46×105 km2, store about 350 Tg aboveground carbon, and play an important role in maintaining China's carbon balance. Boreal forests in this region are facing pressures from repeated fires and timber harvesting activities.The objectives of our study were to evaluate the effects of fire, harvest and their interactions on boreal forest carbon stocks of northeastern China.We used the LANDIS PRO-LINKAGES model-coupling framework to simulate the landscape-level effects of fire and harvest and their interactions over 150 years. Our simulation results suggested that aboveground and soil organic carbon are significantly reduced by fire and harvest over 150 years. The long-term effects of fire and harvest on carbon stocks were greater than the short-term effects in the Great Xing' an Mountains. The total effects of fire-harvest interactions on boreal forests are less than the sum of separate effects of fire and harvest. The response of carbon stocks among ecoregions diverged and was due to the spatial variability of fire and harvest regimes.These results emphasize that fire, harvest, and their interactions play an important role in regulating boreal forest carbon stocks, the extent of fire and harvest effects depended on the intensity of these disturbances.

Modeling forest fire occurrences using count-data mixed models in Qiannan autonomous prefecture of Guizhou province in China.

PubMed

Xiao, Yundan; Zhang, Xiongqing; Ji, Ping

2015-01-01

Forest fires can cause catastrophic damage on natural resources. In the meantime, it can also bring serious economic and social impacts. Meteorological factors play a critical role in establishing conditions favorable for a forest fire. Effective prediction of forest fire occurrences could prevent or minimize losses. This paper uses count data models to analyze fire occurrence data which is likely to be dispersed and frequently contain an excess of zero counts (no fire occurrence). Such data have commonly been analyzed using count data models such as a Poisson model, negative binomial model (NB), zero-inflated models, and hurdle models. Data we used in this paper is collected from Qiannan autonomous prefecture of Guizhou province in China. Using the fire occurrence data from January to April (spring fire season) for the years 1996 through 2007, we introduced random effects to the count data models. In this study, the results indicated that the prediction achieved through NB model provided a more compelling and credible inferential basis for fitting actual forest fire occurrence, and mixed-effects model performed better than corresponding fixed-effects model in forest fire forecasting. Besides, among all meteorological factors, we found that relative humidity and wind speed is highly correlated with fire occurrence.

Modeling Forest Fire Occurrences Using Count-Data Mixed Models in Qiannan Autonomous Prefecture of Guizhou Province in China

PubMed Central

Ji, Ping

2015-01-01

Forest fires can cause catastrophic damage on natural resources. In the meantime, it can also bring serious economic and social impacts. Meteorological factors play a critical role in establishing conditions favorable for a forest fire. Effective prediction of forest fire occurrences could prevent or minimize losses. This paper uses count data models to analyze fire occurrence data which is likely to be dispersed and frequently contain an excess of zero counts (no fire occurrence). Such data have commonly been analyzed using count data models such as a Poisson model, negative binomial model (NB), zero-inflated models, and hurdle models. Data we used in this paper is collected from Qiannan autonomous prefecture of Guizhou province in China. Using the fire occurrence data from January to April (spring fire season) for the years 1996 through 2007, we introduced random effects to the count data models. In this study, the results indicated that the prediction achieved through NB model provided a more compelling and credible inferential basis for fitting actual forest fire occurrence, and mixed-effects model performed better than corresponding fixed-effects model in forest fire forecasting. Besides, among all meteorological factors, we found that relative humidity and wind speed is highly correlated with fire occurrence. PMID:25790309

Historical, observed, and modeled wildfire severity in montane forests of the Colorado Front Range.

PubMed

Sherriff, Rosemary L; Platt, Rutherford V; Veblen, Thomas T; Schoennagel, Tania L; Gartner, Meredith H

2014-01-01

Large recent fires in the western U.S. have contributed to a perception that fire exclusion has caused an unprecedented occurrence of uncharacteristically severe fires, particularly in lower elevation dry pine forests. In the absence of long-term fire severity records, it is unknown how short-term trends compare to fire severity prior to 20th century fire exclusion. This study compares historical (i.e. pre-1920) fire severity with observed modern fire severity and modeled potential fire behavior across 564,413 ha of montane forests of the Colorado Front Range. We used forest structure and tree-ring fire history to characterize fire severity at 232 sites and then modeled historical fire-severity across the entire study area using biophysical variables. Eighteen (7.8%) sites were characterized by low-severity fires and 214 (92.2%) by mixed-severity fires (i.e. including moderate- or high-severity fires). Difference in area of historical versus observed low-severity fire within nine recent (post-1999) large fire perimeters was greatest in lower montane forests. Only 16% of the study area recorded a shift from historical low severity to a higher potential for crown fire today. An historical fire regime of more frequent and low-severity fires at low elevations (<2260 m) supports a convergence of management goals of ecological restoration and fire hazard mitigation in those habitats. In contrast, at higher elevations mixed-severity fires were predominant historically and continue to be so today. Thinning treatments at higher elevations of the montane zone will not return the fire regime to an historic low-severity regime, and are of questionable effectiveness in preventing severe wildfires. Based on present-day fuels, predicted fire behavior under extreme fire weather continues to indicate a mixed-severity fire regime throughout most of the montane forest zone. Recent large wildfires in the Front Range are not fundamentally different from similar events that occurred historically under extreme weather conditions.

Strategies for preventing invasive plant outbreaks after prescribed fire in ponderosa pine forest

USGS Publications Warehouse

Symstad, Amy J.; Newton, Wesley E.; Swanson, Daniel J.

2014-01-01

Land managers use prescribed fire to return a vital process to fire-adapted ecosystems, restore forest structure from a state altered by long-term fire suppression, and reduce wildfire intensity. However, fire often produces favorable conditions for invasive plant species, particularly if it is intense enough to reveal bare mineral soil and open previously closed canopies. Understanding the environmental or fire characteristics that explain post-fire invasive plant abundance would aid managers in efficiently finding and quickly responding to fire-caused infestations. To that end, we used an information-theoretic model-selection approach to assess the relative importance of abiotic environmental characteristics (topoedaphic position, distance from roads), pre-and post-fire biotic environmental characteristics (forest structure, understory vegetation, fuel load), and prescribed fire severity (measured in four different ways) in explaining invasive plant cover in ponderosa pine forest in South Dakota’s Black Hills. Environmental characteristics (distance from roads and post-fire forest structure) alone provided the most explanation of variation (26%) in post-fire cover of Verbascum thapsus (common mullein), but a combination of surface fire severity and environmental characteristics (pre-fire forest structure and distance from roads) explained 36–39% of the variation in post-fire cover of Cirsium arvense (Canada thistle) and all invasives together. For four species and all invasives together, their pre-fire cover explained more variation (26–82%) in post-fire cover than environmental and fire characteristics did, suggesting one strategy for reducing post-fire invasive outbreaks may be to find and control invasives before the fire. Finding them may be difficult, however, since pre-fire environmental characteristics explained only 20% of variation in pre-fire total invasive cover, and less for individual species. Thus, moderating fire intensity or targeting areas of high severity for post-fire invasive control may be the most efficient means for reducing the chances of post-fire invasive plant outbreaks when conducting prescribed fires in this region.

Historical, Observed, and Modeled Wildfire Severity in Montane Forests of the Colorado Front Range

PubMed Central

Sherriff, Rosemary L.; Platt, Rutherford V.; Veblen, Thomas T.; Schoennagel, Tania L.; Gartner, Meredith H.

2014-01-01

Large recent fires in the western U.S. have contributed to a perception that fire exclusion has caused an unprecedented occurrence of uncharacteristically severe fires, particularly in lower elevation dry pine forests. In the absence of long-term fire severity records, it is unknown how short-term trends compare to fire severity prior to 20th century fire exclusion. This study compares historical (i.e. pre-1920) fire severity with observed modern fire severity and modeled potential fire behavior across 564,413 ha of montane forests of the Colorado Front Range. We used forest structure and tree-ring fire history to characterize fire severity at 232 sites and then modeled historical fire-severity across the entire study area using biophysical variables. Eighteen (7.8%) sites were characterized by low-severity fires and 214 (92.2%) by mixed-severity fires (i.e. including moderate- or high-severity fires). Difference in area of historical versus observed low-severity fire within nine recent (post-1999) large fire perimeters was greatest in lower montane forests. Only 16% of the study area recorded a shift from historical low severity to a higher potential for crown fire today. An historical fire regime of more frequent and low-severity fires at low elevations (<2260 m) supports a convergence of management goals of ecological restoration and fire hazard mitigation in those habitats. In contrast, at higher elevations mixed-severity fires were predominant historically and continue to be so today. Thinning treatments at higher elevations of the montane zone will not return the fire regime to an historic low-severity regime, and are of questionable effectiveness in preventing severe wildfires. Based on present-day fuels, predicted fire behavior under extreme fire weather continues to indicate a mixed-severity fire regime throughout most of the montane forest zone. Recent large wildfires in the Front Range are not fundamentally different from similar events that occurred historically under extreme weather conditions. PMID:25251103

Sanford Prescribed Fire Review

Treesearch

Scott Conroy; Jim Saveland; Mark Beighley; John Shive; Joni Ward; Marcus Trujillo; Paul Keller

2003-01-01

The Dixie National Forest has a long-standing history of successfully implementing prescribed fire and suppression programs. The Forest's safety record has been exemplary. The Forest is known Region-wide for its aggressive and innovative prescribed fire program. In particular, the Dixie National Forest is recognized for its leadership in introducing landscape-...

Prescribed fire in upland harwood forests

Treesearch

T.L. Keyser; C.H. Greenberg; H. McNab

2014-01-01

In upland hardwood forests of the Southeastern U.S.,prescribed fire is increasingly used by land managers citing objectives that include hazardous fuels reduction, wildlife habitat improvement, promoting oak regeneration, or restoring forest composition or structure to an historic condition. Research suggests that prescribed fire effects on hardwood forests and...

Early Forest Fire Detection Using Radio-Acoustic Sounding System

PubMed Central

Sahin, Yasar Guneri; Ince, Turker

2009-01-01

Automated early fire detection systems have recently received a significant amount of attention due to their importance in protecting the global environment. Some emergent technologies such as ground-based, satellite-based remote sensing and distributed sensor networks systems have been used to detect forest fires in the early stages. In this study, a radio-acoustic sounding system with fine space and time resolution capabilities for continuous monitoring and early detection of forest fires is proposed. Simulations show that remote thermal mapping of a particular forest region by the proposed system could be a potential solution to the problem of early detection of forest fires. PMID:22573967

Warm Dry Weather Conditions Cause of 2016 Fort McMurray Wild Forest Fire and Associated Air Quality

NASA Astrophysics Data System (ADS)

de Azevedo, S. C.; Singh, R. P.; da Silva, E. A., Sr.

2016-12-01

The climate change is evident from the increasing temperature around the world, day to day life and increasing frequency of natural hazards. The warm and dry conditions are the cause of frequent forest fires around the globe. Forest fires severely affect the air quality and human health. Multi sensor satellites and dense network of ground stations provide information about vegetation health, meteorological, air quality and atmospheric parameters. We have carried out detailed analysis of satellite and ground data of wild forest fire that occurred in May 2016 in Fort McMurray, Alberta, Canada. This wild forest fire destroyed 10 per cent of Fort McMurray's housing and forced more than 90,000 people to evacuate the surrounding areas. Our results show that the warm and dry conditions with low rainfall were the cause of Fort McMurray wild fire. The air quality parameters (particulate matter, CO, ozone, NO2, methane) and greenhouse gases measured from Atmospheric Infrared Sounder (AIRS) satellite show enhanced levels soon after the forest fire. The emissions from the forest fire affected health of population living in surrounding areas up to 300 km radius.

Spatially explicit measurements of forest structure and fire behavior following restoration treatments in dry forests

Treesearch

Justin Paul Ziegler; Chad Hoffman; Michael Battaglia; William Mell

2017-01-01

Restoration treatments in dry forests of the western US often attempt silvicultural practices to restore the historical characteristics of forest structure and fire behavior. However, it is suggested that a reliance on non-spatial metrics of forest stand structure, along with the use of wildland fire behavior models that lack the ability to handle complex structures,...

Long-term effects of prescribed fire on mixed conifer forest structure in the Sierra Nevada, California

Treesearch

Phillip J. Van Mantgem; Nathan L. Stephenson; Eric Knapp; John Barrles; Jon E. Keeley

2011-01-01

The capacity of prescribed fire to restore forest conditions is often judged by changes in forest structure within a few years following burning. However, prescribed fire might have longer-term effects on forest structure, potentially changing treatment assessments. We examined annual changes in forest structure in five 1 ha old-growth plots immediately before...

Using fire to increase the scale, benefits and future maintenance of fuels treatments

Treesearch

Malcolm P. North; Brandon M. Collins; Scott L Stephens

2012-01-01

The Forest Service is implementing a new planning rule and starting to revise forest plans for many of the 155 National Forests. In forests that historically had frequent fire regimes, the scale of current fuels reduction treatments has often been too limited to affect fire severity and the Forest Service has predominantly focused on suppression. In addition to...

Climatic stress increases forest fire severity across the western United States.

PubMed

van Mantgem, Phillip J; Nesmith, Jonathan C B; Keifer, MaryBeth; Knapp, Eric E; Flint, Alan; Flint, Lorriane

2013-09-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after accounting for fire defences and injuries, and appeared to influence the effects of crown and stem injuries. Climate and fire interactions did not vary substantially across geographical regions, major genera and tree sizes. Our findings support recent physiological evidence showing that both drought and heating from fire can impair xylem conductivity. Warming trends have been linked to increasing probabilities of severe fire weather and fire spread; our results suggest that warming may also increase forest fire severity (the number of trees killed) independent of fire intensity (the amount of heat released during a fire). Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Fire-induced changes in boreal forest canopy volume and soil organic matter from multi-temporal airborne lidar

NASA Astrophysics Data System (ADS)

Alonzo, M.; Cook, B.; Andersen, H. E.; Babcock, C. R.; Morton, D. C.

2016-12-01

Fire in boreal forests initiates a cascade of biogeochemical and biophysical processes. Over typical fire return intervals, net radiative forcing from boreal forest fires depends on the offsetting impacts of greenhouse gas emissions and post-fire changes in land surface albedo. Whether boreal forest fires warm or cool the climate over these multi-decadal intervals depends on the magnitude of fire emissions and the time scales of decomposition, albedo changes, and forest regrowth. Our understanding of vegetation and surface organic matter (SOM) changes from boreal forest fires is shaped by field measurements and moderate resolution remote sensing data. Intensive field plot measurements offer detailed data on overstory, understory, and SOM changes from fire, but sparse plot data can be difficult to extend across the heterogeneous boreal forest landscape. Conversely, satellite measurements of burn severity are spatially extensive but only provide proxy measures of fire effects. In this research, we seek to bridge the scale gap between existing intensive and extensive methods using a combination of airborne lidar data and time series of Landsat data to evaluate pre- and post-fire conditions across Alaska's Kenai Peninsula. Lidar-based estimates of pre-fire stand structure and composition were essential to characterize the loss of canopy volume from fires between 2001 and 2014, quantify transitions from live to dead standing carbon pools, and isolate vegetation recovery following fire over 1 to 13 year time scales. Results from this study demonstrate the utility of lidar for estimating pre-fire structure and species composition at the scale of individual tree crowns. Multi-temporal airborne lidar data also provide essential insights regarding the heterogeneity of canopy and SOM losses at a sub-Landsat pixel scale. Fire effects are forest-structure and species dependent with variable temporal lags in carbon release due to delayed mortality (>5 years post fire) and standing dead trees. Establishing the spatial and temporal scales of canopy structural change will aid in constraining estimates of net radiative forcing from both carbon release and albedo in the years following fire.

Forest construction infrastructures for the prevision, suppression, and protection before and after forest fires

NASA Astrophysics Data System (ADS)

Drosos, Vasileios C.; Giannoulas, Vasileios J.; Daoutis, Christodoulos

2014-08-01

Climatic changes cause temperature rise and thus increase the risk of forest fires. In Greece the forests with the greatest risk to fire are usually those located near residential and tourist areas where there are major pressures on land use changes, while there are no currently guaranteed cadastral maps and defined title deeds because of the lack of National and Forest Cadastre. In these areas the deliberate causes of forest fires are at a percentage more than 50%. This study focuses on the forest opening up model concerning both the prevention and suppression of forest fires. The most urgent interventions that can be done after the fire destructions is also studied in relation to soil protection constructions, in order to minimize the erosion and the torrential conditions. Digital orthophotos were used in order to produce and analyze spatial data using Geographical Information Systems (GIS). Initially, Digital Elevation Models were generated, based on photogrammetry and forest areas as well as the forest road network were mapped. Road density, road distance, skidding distance and the opening up percentage were accurately measured for a forest complex. Finally, conclusions and suggestions have been drawn about the environmental compatibility of forest protection and wood harvesting works. In particular the contribution of modern technologies such as digital photogrammetry, remote sensing and Geographical Information Systems is very important, allowing reliable, effective and fast process of spatial analysis contributing to a successful planning of opening up works and fire protection.

[Estimation of carbonaceous gases emission from forest fires in Xiao Xing'an Mountains of Northeast China in 1953-2011].

PubMed

Hu, Hai-Qing; Luo, Bi-Zhen; Wei, Shu-Jing; Sun, Long; Wei, Shu-Wei; Wen, Zheng-Min

2013-11-01

Based on the forest resources investigation data and the forest fire inventory in 1953-2011, in combining with our field research in burned areas and our laboratory experiments, this paper estimated the carbonaceous gases carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), and nonmethane hydrocarbons (NMHC) emission from the forest fires in Xiao Xing' an Mountains of Heilongjiang Province, Northeast China in 1953-2011. The total carbon emission from the forest fires in the Xiao Xing'an Mountains in 1953-2011 was 1.12 x 10(7) t, and the annual emission was averagely 1.90 x10(5) t, accounting for 1.7% of the annual average total carbon emission from the forest fires in China. The emission of CO2, CO, CH4, and NMHC was 3.39 x 10(7), 1.94 x 10(5), 1.09 x 10(5), and 7.46 x 10(4) t, respectively, and the corresponding annual average emission was 5.74 x 10(5), 3.29 x 10(4), 1.85 x 10(3), and 1.27 x 10(3) t, accounting for 1.4%, 1.2%, 1.7%, and 1.1% of the annual carbonaceous gases emitted from the forest fires in China, respectively. The combustion efficiency and the carbon emission per unit burned area of different forest types decreased in order of coniferous forest > broad-leaved forest > coniferous broadleaved mixed forest. Some rational forest fire management measures were put forward.

A numerical solution of the problem of crown forest fire initiation and spread

NASA Astrophysics Data System (ADS)

Marzaeva, S. I.; Galtseva, O. V.

2018-05-01

Mathematical model of forest fire was based on an analysis of known experimental data and using concept and methods from reactive media mechanics. The study takes in to account the mutual interaction of the forest fires and three-dimensional atmosphere flows. The research is done by means of mathematical modeling of physical processes. It is based on numerical solution of Reynolds equations for chemical components and equations of energy conservation for gaseous and condensed phases. It is assumed that the forest during a forest fire can be modeled as a two-temperature multiphase non-deformable porous reactive medium. A discrete analog for the system of equations was obtained by means of the control volume method. The developed model of forest fire initiation and spreading would make it possible to obtain a detailed picture of the variation in the velocity, temperature and chemical species concentration fields with time. Mathematical model and the result of the calculation give an opportunity to evaluate critical conditions of the forest fire initiation and spread which allows applying the given model for of means for preventing fires.

Opposing effects of fire severity on climate feedbacks in Siberian larch forests

NASA Astrophysics Data System (ADS)

Loranty, M. M.; Alexander, H. D.; Natali, S.; Kropp, H.; Mack, M. C.; Bunn, A. G.; Davydov, S. P.; Erb, A.; Kholodov, A. L.; Schaaf, C.; Wang, Z.; Zimov, N.; Zimov, S. A.

2017-12-01

Boreal larch forests in northeastern Siberia comprise nearly 25% of the continuous permafrost zone. Structural and functional changes in these ecosystems will have important climate feedbacks at regional and global scales. Like boreal ecosystems in North America, fire is an important determinant of landscape scale forest distribution, and fire regimes are intensifying as climate warms. In Siberian larch forests are dominated by a single tree species, and there is evidence that fire severity influences post-fire forest density via impacts on seedling establishment. The extent to which these effects occur, or persist, and the associated climate feedbacks are not well quantified. In this study we use forest stand inventories, in situ observations, and satellite remote sensing to examine: 1) variation in forest density within and between fire scars, and 2) changes in land surface albedo and active layer dynamics associated with forest density variation. At the landscape scale we observed declines in Landsat derived albedo as forests recovered in the first several decades after fire, though canopy cover varied widely within and between individual fire scars. Within an individual mid-successional fire scar ( 75 years) we observed canopy cover ranging from 15-90% with correspondingly large ranges of albedo during periods of snow cover, and relatively small differences in albedo during the growing season. We found an inverse relationship between canopy density and soil temperature within this fire scar; high-density low-albedo stands had cooler soils and shallower active layers, while low-density stands had warmer soils and deeper active layers. Intensive energy balance measurements at a high- and low- density site show that canopy cover alters the magnitude and timing of ground heat fluxes that affect active layer properties. Our results show that fire impacts on stand structure in Siberian larch forests affect land surface albedo and active layer dynamics in ways that may lead to opposing climate feedbacks. At effectively large scales these changes constitute positive and negative climate feedbacks, respectively. Accurate predictive understanding of terrestrial Arctic climate feedbacks requires improved knowledge regarding the ecological consequences of changing fire regimes in Siberian boreal forests.

Best Longitudinal Adjustment of Satellite Trajectories for the Observation of Forest Fires (Blastoff): A Stochastic Programming Approach to Satellite System Design

NASA Astrophysics Data System (ADS)

Hoskins, Aaron B.

Forest fires cause a significant amount of damage and destruction each year. Optimally dispatching resources reduces the amount of damage a forest fire can cause. Models predict the fire spread to provide the data required to optimally dispatch resources. However, the models are only as accurate as the data used to build them. Satellites are one valuable tool in the collection of data for the forest fire models. Satellites provide data on the types of vegetation, the wind speed and direction, the soil moisture content, etc. The current operating paradigm is to passively collect data when possible. However, images from directly overhead provide better resolution and are easier to process. Maneuvering a constellation of satellites to fly directly over the forest fire provides higher quality data than is achieved with the current operating paradigm. Before launch, the location of the forest fire is unknown. Therefore, it is impossible to optimize the initial orbits for the satellites. Instead, the expected cost of maneuvering to observe the forest fire determines the optimal initial orbits. A two-stage stochastic programming approach is well suited for this class of problem where initial decisions are made with an uncertain future and then subsequent decisions are made once a scenario is realized. A repeat ground track orbit provides a non-maneuvering, natural solution providing a daily flyover of the forest fire. However, additional maneuvers provide a second daily flyover of the forest fire. The additional maneuvering comes at a significant cost in terms of additional fuel, but provides more data collection opportunities. After data are collected, ground stations receive the data for processing. Optimally selecting the ground station locations reduce the number of built ground stations and reduces the data fusion issues. However, the location of the forest fire alters the optimal ground station sites. A two-stage stochastic programming approach optimizes the selection of ground stations to maximize the expected amount of data downloaded from a satellite. The approaches of selecting initial orbits and ground station locations including uncertainty will provide a robust system to reduce the amount of damage caused by forest fires.

Characterization of biomass burning aerosols from forest fire in Indonesia

NASA Astrophysics Data System (ADS)

Fujii, Y.; Iriana, W.; Okumura, M.; Lestari, P.; Tohno, S.; Akira, M.; Okuda, T.

2012-12-01

Biomass burning (forest fire, wild fire) is a major source of pollutants, generating an estimate of 104 Tg per year of aerosol particles worldwide. These particles have adverse human health effects and can affect the radiation budget and climate directly and indirectly. Eighty percent of biomass burning aerosols are generated in the tropics and about thirty percent of them originate in the tropical regions of Asia (Andreae, 1991). Several recent studies have reported on the organic compositions of biomass burning aerosols in the tropical regions of South America and Africa, however, there is little data about forest fire aerosols in the tropical regions of Asia. It is important to characterize biomass burning aerosols in the tropical regions of Asia because the aerosol properties vary between fires depending on type and moisture of wood, combustion phase, wind conditions, and several other variables (Reid et al., 2005). We have characterized PM2.5 fractions of biomass burning aerosols emitted from forest fire in Indonesia. During the dry season in 2012, PM2.5 aerosols from several forest fires occurring in Riau, Sumatra, Indonesia were collected on quartz and teflon filters with two mini-volume samplers. Background aerosols in forest were sampled during transition period of rainy season to dry season (baseline period). Samples were analyzed with several analytical instruments. The carbonaceous content (organic and elemental carbon, OC and EC) of the aerosols was analyzed by a thermal optical reflectance technique using IMPROVE protocol. The metal, inorganic ion and organic components of the aerosols were analyzed by X-ray Fluorescence (XRF), ion chromatography and gas chromatography-mass spectrometry, respectively. There was a great difference of chemical composition between forest fire and non-forest fire samples. Smoke aerosols for forest fires events were composed of ~ 45 % OC and ~ 2.5 % EC. On the other hand, background aerosols for baseline periods were composed of ~ 18 % OC and ~ 10 % EC. OC/EC ratio was consistently lower (~ 2) for baseline periods than that for forest fire events (~ 20). OC and EC concentrations for forest fire events were more than 150 times and 10 times higher than those for baseline periods.

Land surveys show regional variability of historical fire regimes and dry forest structure of the western United States.

PubMed

Baker, William L; Williams, Mark A

2018-03-01

An understanding of how historical fire and structure in dry forests (ponderosa pine, dry mixed conifer) varied across the western United States remains incomplete. Yet, fire strongly affects ecosystem services, and forest restoration programs are underway. We used General Land Office survey reconstructions from the late 1800s across 11 landscapes covering ~1.9 million ha in four states to analyze spatial variation in fire regimes and forest structure. We first synthesized the state of validation of our methods using 20 modern validations, 53 historical cross-validations, and corroborating evidence. These show our method creates accurate reconstructions with low errors. One independent modern test reported high error, but did not replicate our method and made many calculation errors. Using reconstructed parameters of historical fire regimes and forest structure from our validated methods, forests were found to be non-uniform across the 11 landscapes, but grouped together in three geographical areas. Each had a mixture of fire severities, but dominated by low-severity fire and low median tree density in Arizona, mixed-severity fire and intermediate to high median tree density in Oregon-California, and high-severity fire and intermediate median tree density in Colorado. Programs to restore fire and forest structure could benefit from regional frameworks, rather than one size fits all. © 2018 by the Ecological Society of America.

The experience of community residents in a fire-prone ecosystem: A case study on the San Bernardino National Forest

Treesearch

George T. Cvetkovich; Patricia L. Winter

2008-01-01

This report presents results from a study of San Bernardino National Forest community residents’ experiences with and perceptions of fire, fire management, and the Forest Service. Using self-administered surveys and focus group discussions, we found that participants had personal experiences with fire, were concerned about fire, and felt knowledgeable about effective...

Fire exclusion as a disturbance in the temperate forests of the USA: examples from longleaf pine forests

Treesearch

W. Keith Moser; Dale D. Wade

2005-01-01

Forest fires are a disturbance where the effects can range from benign to extreme devastation within a given ecosystem. The stage of stand development coupled with prior management dictates the amount and composition of potential fuels. Thus, fire policy exerts a strong influence on fire effects. Changes in cultural acceptance and use of tire typically drive fire...

Proposed wildland fire amendment to the Coronado National Forest Land and Resource Management Plan

Treesearch

Sherry A. Tune; Erin M. Boyle

2005-01-01

The Coronado National Forest proposed amending its 1986 Land and Resource Management Plan to conform to the 2001 Federal Wildland Fire Management Policy. This Policy emphasizes fire’s essential role in maintaining natural ecosystems and allows a broader range of management options for wildland fires. Under the current Forest Plan, fires must be suppressed in areas...

Fire and fire surrogate study in the Sierra Nevada: evaluating restoration treatments at Blodgett Forest and Sequoia National Park

Treesearch

Eric E. Knapp; Scott L. Stephens; James D. McIver; Jason J. Moghaddas; Jon E. Keeley

2004-01-01

Management practices have altered both the structure and function of forests throughout the United States. Some of the most dramatic changes have resulted from fire exclusion, especially in forests that historically experienced relatively frequent, low- to moderate-intensity fire regimes. In the Sierra Nevada, fire exclusion is believed to have resulted in widespread...

Assessment of fire effects based on Forest Inventory and Analysis data and a long-term fire mapping data set

Treesearch

John D. Shaw; Sara A. Goeking; James Menlove; Charles E. Werstak

2017-01-01

Integration of Forest Inventory and Analysis (FIA) plot data with Monitoring Trends in Burn Severity (MTBS) data can provide new information about fire effects on forests. This integration allowed broad-scale assessment of the cover types burned in large fires, the relationship between prefire stand conditions and fire severity, and postfire stand conditions. Of the 42...

A Drought Index for Forest Fire Control

Treesearch

John J. Keetch; George M. Byram

1968-01-01

The moisture content of the upper soil, as well as that of the covering layer of duff, has an important effect on the fire suppression effort in forest and wildland areas. In certain forested areas of the United States, fires in deep duff fuels are of particular concern to the fire control manager. When these fuels are dry, fires burn deeply, dam-age is excessive, and...

Fire effects in southwestern forests: Proceedings of the second La Mesa Fire Symposium

Treesearch

Craig D. Allen

1996-01-01

In 1977, the La Mesa Fire burned across 15,444 acres of ponderosa pine forests on the adjoining lands of Bandelier National Monument, the Santa Fe National Forest, and Los Alamos National Laboratory. Following this event, several fire effects studies were initiated. The 16 papers herein document longer-term knowledge gained about the ecological effects of the fire and...

Ecological consequences of alternative fuel reduction treatments in seasonally dry forests: the national fire and fire surrogate study

Treesearch

J.D. McIver; C.J. Fettig

2010-01-01

This special issue of Forest Science features the national Fire and Fire Surrogate study (FFS), a niultisite, multivariate research project that evaluates the ecological consequences of prescribed fire and its mechanical surrogates in seasonally dry forests of the United States. The need for a comprehensive national FFS study stemmed from concern that information on...

Tree mortality based fire severity classification for forest inventories: A Pacific Northwest national forests example

Treesearch

Thomas R. Whittier; Andrew N. Gray

2016-01-01

Determining how the frequency, severity, and extent of forest fires are changing in response to changes in management and climate is a key concern in many regions where fire is an important natural disturbance. In the USA the only national-scale fire severity classification uses satellite image changedetection to produce maps for large (>400 ha) fires, and is...

Prioritizing forest fuels treatments based on the probability of high-severity fire restores adaptive capacity in Sierran forests

Treesearch

Daniel J. Krofcheck; Matthew D. Hurteau; Robert M. Scheller; E. Louise Loudermilk

2017-01-01

In frequent fire forests of the western United States, a legacy of fire suppression coupled with increases in fire weather severity have altered fire regimes and vegetation dynamics. When coupled with projected climate change, these conditions have the potential to lead to vegetation type change and altered carbon (C) dynamics. In the Sierra Nevada, fuels...

Assessing fire impacts on the carbon stability of fire-tolerant forests.

PubMed

Bennett, Lauren T; Bruce, Matthew J; Machunter, Josephine; Kohout, Michele; Krishnaraj, Saravanan Jangammanaidu; Aponte, Cristina

2017-12-01

The carbon stability of fire-tolerant forests is often assumed but less frequently assessed, limiting the potential to anticipate threats to forest carbon posed by predicted increases in forest fire activity. Assessing the carbon stability of fire-tolerant forests requires multi-indicator approaches that recognize the myriad ways that fires influence the carbon balance, including combustion, deposition of pyrogenic material, and tree death, post-fire decomposition, recruitment, and growth. Five years after a large-scale wildfire in southeastern Australia, we assessed the impacts of low- and high-severity wildfire, with and without prescribed fire (≤10 yr before), on carbon stocks in multiple pools, and on carbon stability indicators (carbon stock percentages in live trees and in small trees, and carbon stocks in char and fuels) in fire-tolerant eucalypt forests. Relative to unburned forest, high-severity wildfire decreased short-term (five-year) carbon stability by significantly decreasing live tree carbon stocks and percentage stocks in live standing trees (reflecting elevated tree mortality), by increasing the percentage of live tree carbon in small trees (those vulnerable to the next fire), and by potentially increasing the probability of another fire through increased elevated fine fuel loads. In contrast, low-severity wildfire enhanced carbon stability by having negligible effects on aboveground stocks and indicators, and by significantly increasing carbon stocks in char and, in particular, soils, indicating pyrogenic carbon accumulation. Overall, recent preceding prescribed fire did not markedly influence wildfire effects on short-term carbon stability at stand scales. Despite wide confidence intervals around mean stock differences, indicating uncertainty about the magnitude of fire effects in these natural forests, our assessment highlights the need for active management of carbon assets in fire-tolerant eucalypt forests under contemporary fire regimes. Decreased live tree carbon and increased reliance on younger cohorts for carbon recovery after high-severity wildfire could increase vulnerabilities to imminent fires, leading to decisions about interventions to maintain the productivity of some stands. Our multi-indicator assessment also highlights the importance of considering all carbon pools, particularly pyrogenic reservoirs like soils, when evaluating the potential for prescribed fire regimes to mitigate the carbon costs of wildfires in fire-prone landscapes. © 2017 by the Ecological Society of America.

Cross amplification of 15 SSR markers in the genus Fraxinus

Treesearch

Andrea G. Noakes; Teodora Best; Margaret E. Stanton; Jennifer Koch; Jeanne Romero-Severson

2014-01-01

Ash (Fraxinus, Oleaceae) species occur on most continents, within a wide range of forest tree communities. Emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), introduced into the U.S. from Asia in the late twentieth century, has caused widespread mortality, primarily in green ash, Fraxinus...

Physical factors affecting the mutagenicity of fly ash from a coal-fired power plant.

PubMed

Fisher, G L; Chrisp, C E; Raabe, O G

1979-05-25

The two finest, most respirable coal fly ash fractions collected from the smokestack of a power plant were more mutagenic than two coarser fractions. Mutagenicity was evaluated in the histidine-requiring bacterial strains TA 1538, TA 98, and TA 100 of Salmonella typhimurium. Ash samples collected from the hoppers of an electrostatic precipitator in the plant were not mutagenic. The mutagens in coal fly ash were resistant to x-ray or ultraviolet irradiation, possibly as a result of stabilization by fly ash surfaces. All mutagenic activity is lost with heating to 350 degrees C.

The ectomycorrhizal community of conifer stands on peat soils 12 years after fertilization with wood ash.

PubMed

Klavina, Darta; Pennanen, Taina; Gaitnieks, Talis; Velmala, Sannakajsa; Lazdins, Andis; Lazdina, Dagnija; Menkis, Audrius

2016-02-01

We studied long-term effects of fertilization with wood ash on biomass, vitality and mycorrhizal colonization of fine roots in three conifer forest stands growing in Vacciniosa turf. mel. (V), Myrtillosa turf. mel. (M) and Myrtillosa turf. mel./Caricoso-phragmitosa (MC) forest types on peat soils. Fertilization trials amounting 5 kg/m(2) of wood ash were established 12 years prior to this study. A total of 63 soil samples with roots were collected and analysed. Ectomycorrhizal (ECM) fungi in roots were identified by morphotyping and sequencing of the fungal internal transcribed spacer (ITS) region. In all forest types, fine root biomass was higher in fertilized plots than in control plots. In M forest type, proportion of living fine roots was greater in fertilized plots than in control plots, while in V and MC, the result was opposite. Fifty ECM species were identified, of which eight were common to both fertilized and control plots. Species richness and Shannon diversity index were generally higher in fertilized plots than in control plots. The most common species in fertilized plots were Amphinema byssoides (17.8%) and Tuber cf. anniae (12.2%), while in control plots, it was Tylospora asterophora (18.5%) and Lactarius tabidus (20.3%). Our results showed that forest fertilization with wood ash has long-lasting effect on diversity and composition of ECM fungal communities.

Fire-induced Carbon Emissions and Regrowth Uptake in Western U.S. Forests: Documenting Variation Across Forest Types, Fire Severity, and Climate Regions

NASA Technical Reports Server (NTRS)

Ghimire, Bardan; Williams, Christopher A.; Collatz, George James; Vanderhoof, Melanie

2012-01-01

The forest area in the western United States that burns annually is increasing with warmer temperatures, more frequent droughts, and higher fuel densities. Studies that examine fire effects for regional carbon balances have tended to either focus on individual fires as examples or adopt generalizations without considering how forest type, fire severity, and regional climate influence carbon legacies. This study provides a more detailed characterization of fire effects and quantifies the full carbon impacts in relation to direct emissions, slow release of fire-killed biomass, and net carbon uptake from forest regrowth. We find important variations in fire-induced mortality and combustion across carbon pools (leaf, live wood, dead wood, litter, and duff) and across low- to high-severity classes. This corresponds to fire-induced direct emissions from 1984 to 2008 averaging 4 TgC/yr and biomass killed averaging 10.5 TgC/yr, with average burn area of 2723 sq km/yr across the western United States. These direct emission and biomass killed rates were 1.4 and 3.7 times higher, respectively, for high-severity fires than those for low-severity fires. The results show that forest regrowth varies greatly by forest type and with severity and that these factors impose a sustained carbon uptake legacy. The western U.S. fires between 1984 and 2008 imposed a net source of 12.3 TgC/yr in 2008, accounting for both direct fire emissions (9.5 TgC/yr) and heterotrophic decomposition of fire-killed biomass (6.1 TgC yr1) as well as contemporary regrowth sinks (3.3 TgC/yr). A sizeable trend exists toward increasing emissions as a larger area burns annually.

Allocation strategies of savanna and forest tree seedlings in response to fire and shading: outcomes of a field experiment

NASA Astrophysics Data System (ADS)

Gignoux, Jacques; Konaté, Souleymane; Lahoreau, Gaëlle; Le Roux, Xavier; Simioni, Guillaume

2016-12-01

The forest-savanna ecotone may be very sharp in fire-prone areas. Fire and competition for light play key roles in its maintenance, as forest and savanna tree seedlings are quickly excluded from the other ecosystem. We hypothesized a tradeoff between seedling traits linked to fire resistance and to competition for light to explain these exclusions. We compared growth- and survival-related traits of two savanna and two forest species in response to shading and fire in a field experiment. To interpret the results, we decomposed our broad hypothesis into elementary tradeoffs linked to three constraints, biomass allocation, plant architecture, and shade tolerance, that characterize both savanna and adjacent forest ecosystems. All seedlings reached similar biomasses, but forest seedlings grew taller. Savanna seedlings better survived fire after topkill and required ten times less biomass than forest seedlings to survive. Finally, only savanna seedlings responded to shading. Although results were consistent with the classification of our species as mostly adapted to shade tolerance, competition for light in the open, and fire tolerance, they raised new questions: how could savanna seedlings survive better with a 10-times lower biomass than forest seedlings? Is their shade intolerance sufficient to exclude them from forest understory?

75 FR 52713 - Nationwide Aerial Application of Fire Retardant on National Forest System Lands

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-27

... DEPARTMENT OF AGRICULTURE Forest Service Nationwide Aerial Application of Fire Retardant on... statement for the continued nationwide aerial application of fire retardant on National Forest System lands... 26667, Salt Lake City, UT 84126-0667. Comments may also be sent via e- mail to Fire[email protected

A guide for salvaging white pine injured by forest fires

Treesearch

Thomas W. McConkey; Donald R. Gedney

1951-01-01

White pine forests are severely damaged by forest fires. Generally a fire kills all trees less than 20 feet high immediately. Larger trees may die later, depending on the degree of injury. Salvage operations must be started soon after a fire, because insects and fungi quickly attack trees that are killed.

A review of the relationships between drought and forest fire in the United States

Treesearch

Jeremy S. Littell; David L. Peterson; Karin L. Riley; Yongqiang Liu; Charlie H. Luce

2016-01-01

The historical and presettlement relationships between drought and wildfire are well documented in North America, with forest fire occurrence and area clearly increasing in response to drought. There is also evidence that drought interacts with other controls (forest productivity, topography, fire weather, management activities) to affect fire intensity,...

Refining the oak-fire hypothesis for management of oak-dominated forests of the eastern United States

Treesearch

Mary A. Arthur; Heather D. Alexander; Daniel C. Dey; Callie J. Schweitzer; David L. Loftis

2012-01-01

Prescribed fires are increasingly implemented throughout eastern deciduous forests to accomplish various management objectives, including maintenance of oak-dominated (Quercus spp.) forests. Despite a regional research-based understanding of prehistoric and historic fire regimes, a parallel understanding of contemporary fire use to preserve oak...

Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

PubMed Central

Odion, Dennis C.; Hanson, Chad T.; Baker, William L.; DellaSala, Dominick A.; Williams, Mark A.

2016-01-01

In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa) and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue) agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA) plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper. PMID:27195808

Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

PubMed

Odion, Dennis C; Hanson, Chad T; Baker, William L; DellaSala, Dominick A; Williams, Mark A

2016-01-01

In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa) and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue) agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA) plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper.

Amazon Forest Responses to Drought and Fire

NASA Astrophysics Data System (ADS)

Morton, D. C.

2015-12-01

Deforestation and agricultural land uses provide a consistent source of ignitions along the Amazon frontier during the dry season. The risk of understory fires in Amazon forests is amplified by drought conditions, when fires at the forest edge may spread for weeks before rains begin. Fire activity also impacts the regional response of intact forests to drought through diffuse light effects and nutrient redistribution, highlighting the complexity of feedbacks in this coupled human and natural system. This talk will focus on recent advances in our understanding of fire-climate feedbacks in the Amazon, building on research themes initiated under NASA's Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA). NASA's LBA program began in the wake of the 1997-1998 El Niño, a strong event that exposed the vulnerability of Amazon forests to drought and fire under current climate and projections of climate change. With forecasts of another strong El Niño event in 2015-2016, this talk will provide a multi-scale synthesis of Amazon forest responses to drought and fire based on field measurements, airborne lidar data, and satellite observations of fires, rainfall, and terrestrial water storage. These studies offer new insights into the mechanisms governing fire season severity in the southern Amazon and regional variability in carbon losses from understory fires. The contributions from remote sensing to our understanding of drought and fire in Amazon forests reflect the legacy of NASA's LBA program and the sustained commitment to interdisciplinary research across the Amazon region.

Respiratory tract deposition efficiencies: evaluation of effects from smoke released in the Cerro Grande forest fire.

PubMed

Schöllnberger, H; Aden, J; Scott, B R

2002-01-01

Forest-fire smoke inhaled by humans can cause various health effects. This smoke contains toxic chemicals and naturally occurring radionuclides. In northern New Mexico, a large wildfire occurred in May 2000. Known as the Cerro Grande Fire, it devastated the town of Los Alamos and damaged Los Alamos National Laboratory (LANL). Residents were concerned about the possible dissemination of radionuclides from LANL via smoke from the fire. To evaluate potential health effects of inhaling radionuclides contained in the smoke from the Cerro Grande Fire, it was first necessary to evaluate how much smoke would deposit in the human respiratory tract. The purpose of this study was to evaluate respiratory-tract deposition efficiencies of airborne forest-fire smoke for persons of different ages exposed while inside their homes. Potential non-radiological health effects of a forest fire are reviewed. The deposition efficiencies presented can be used to evaluate in-home smoke deposition in the respiratory tract and expected radionuclide intake related to forest fires. The impact of smoke exposure on firemen fighting a forest fire is quantitatively discussed and compared. They primarily inhaled forest-fire smoke while outdoors where the smoke concentration was much higher than inside. Radionuclides released at the LANL site via the Cerro Grande Fire were restricted to naturally occurring radionuclides from burning trees and vegetation. Radiation doses from inhaled airborne radionuclides to individuals inside and outside the Los Alamos area were likely very small.

Post-fire reconstructions of fire intensity from fire severity data: quantifying the role of spatial variability of fire intensity on forest dynamics

NASA Astrophysics Data System (ADS)

Baker, Patrick; Oborne, Lisa

2015-04-01

Large, high-intensity fires have direct and long-lasting effects on forest ecosystems and present a serious threat to human life and property. However, even within the most catastrophic fires there is important variability in local-scale intensity that has important ramifications for forest mortality and regeneration. Quantifying this variability is difficult due to the rarity of catastrophic fire events, the extreme conditions at the time of the fires, and their large spatial extent. Instead fire severity is typically measured or estimated from observed patterns of vegetation mortality; however, differences in species- and size-specific responses to fires often makes fire severity a poor proxy for fire intensity. We developed a statistical method using simple, plot-based measurements of individual tree mortality to simultaneously estimate plot-level fire intensity and species-specific mortality patterns as a function of tree size. We applied our approach to an area of forest burned in the catastrophic Black Saturday fires that occurred near Melbourne, Australia, in February 2009. Despite being the most devastating fire in the past 70 years and our plots being located in the area that experienced some of the most intense fires in the 350,000 ha fire complex, we found that the estimated fire intensity was highly variable at multiple spatial scales. All eight tree species in our study differed in their susceptibility to fire-induced mortality, particularly among the largest size classes. We also found that seedling height and species richness of the post-fire seedling communities were both positively correlated with fire intensity. Spatial variability in disturbance intensity has important, but poorly understood, consequences for the short- and long-term dynamics of forests in the wake of catastrophic wildfires. Our study provides a tool to estimate fire intensity after a fire has passed, allowing new opportunities for linking spatial variability in fire intensity to forest ecosystem dynamics.

Size fractionation as a tool for separating charcoal of different fuel source and recalcitrance in the wildfire ash layer.

PubMed

Mastrolonardo, Giovanni; Hudspith, Victoria A; Francioso, Ornella; Rumpel, Cornelia; Montecchio, Daniela; Doerr, Stefan H; Certini, Giacomo

2017-10-01

Charcoal is a heterogeneous material exhibiting a diverse range of properties. This variability represents a serious challenge in studies that use the properties of natural charcoal for reconstructing wildfires history in terrestrial ecosystems. In this study, we tested the hypothesis that particle size is a sufficiently robust indicator for separating forest wildfire combustion products into fractions with distinct properties. For this purpose, we examined two different forest environments affected by contrasting wildfires in terms of severity: an eucalypt forest in Australia, which experienced an extremely severe wildfire, and a Mediterranean pine forest in Italy, which burned to moderate severity. We fractionated the ash/charcoal layers collected on the ground into four size fractions (>2, 2-1, 1-0.5, <0.5mm) and analysed them for mineral ash content, elemental composition, chemical structure (by IR spectroscopy), fuel source and charcoal reflectance (by reflected-light microscopy), and chemical/thermal recalcitrance (by chemical and thermal oxidation). At both sites, the finest fraction (<0.5mm) had, by far, the greatest mass. The C concentration and C/N ratio decreased with decreasing size fraction, while pH and the mineral ash content followed the opposite trend. The coarser fractions showed higher contribution of amorphous carbon and stronger recalcitrance. We also observed that certain fuel types were preferentially represented by particular size fractions. We conclude that the differences between ash/charcoal size fractions were most likely primarily imposed by fuel source and secondarily by burning conditions. Size fractionation can therefore serve as a valuable tool to characterise the forest wildfire combustion products, as each fraction displays a narrower range of properties than the whole sample. We propose the mineral ash content of the fractions as criterion for selecting the appropriate number of fractions to analyse. Copyright © 2016. Published by Elsevier B.V.

Visibility analysis of fire lookout towers in the Boyabat State Forest Enterprise in Turkey.

PubMed

Kucuk, Omer; Topaloglu, Ozer; Altunel, Arif Oguz; Cetin, Mehmet

2017-07-01

For a successful fire suppression, it is essential to detect and intervene forest fires as early as possible. Fire lookout towers are crucial assets in detecting forest fires, in addition to other technological advancements. In this study, we performed a visibility analysis on a network of fire lookout towers currently operating in a relatively fire-prone region in Turkey's Western Black Sea region. Some of these towers had not been functioning properly; it was proposed that these be taken out of the grid and replaced with new ones. The percentage of visible areas under the current network of fire lookout towers was 73%; it could rise to 81% with the addition of newly proposed towers. This study was the first research to conduct a visibility analysis of current and newly proposed fire lookout towers in the Western Black Sea region and focus on its forest fire problem.

Implications of the spatial dynamics of fire spread for the bistability of savanna and forest.

PubMed

Schertzer, E; Staver, A C; Levin, S A

2015-01-01

The role of fire in expanding the global distribution of savanna is well recognized. Empirical observations and modeling suggest that fire spread has a threshold response to fuel-layer continuity, which sets up a positive feedback that maintains savanna-forest bistability. However, modeling has so far failed to examine fire spread as a spatial process that interacts with vegetation. Here, we use simple, well-supported assumptions about fire spread as an infection process and its effects on trees to ask whether spatial dynamics qualitatively change the potential for savanna-forest bistability. We show that the spatial effects of fire spread are the fundamental reason that bistability is possible: because fire spread is an infection process, it exhibits a threshold response to fuel continuity followed by a rapid increase in fire size. Other ecological processes affecting fire spread may also contribute including temporal variability in demography or fire spread. Finally, including the potential for spatial aggregation increases the potential both for savanna-forest bistability and for savanna and forest to coexist in a landscape mosaic.

Prescribed fire as the minimum tool for wilderness forest and fire regime restoration: a case study from the Sierra Nevada, California

Treesearch

MaryBeth Keifer; Nathan L. Stephenson; Jeff Manley

2000-01-01

Changes in forest structure were monitored in areas treated with prescribed fire in Sequoia and Kings Canyon National Parks. Five years after the initial prescribed fires, tree density was reduced by 61% in the giant sequoia-mixed conifer forest, with the greatest reduction in the smaller trees. This post-burn forest structure falls within the range that may have been...

The carbon debt from Amazon forest degradation: integrating airborne lidar, field measurements, and an ecosystem demography model.

NASA Astrophysics Data System (ADS)

Longo, M.; Keller, M. M.; dos-Santos, M. N.; Scaranello, M. A., Sr.; Pinagé, E. R.; Leitold, V.; Morton, D. C.

2016-12-01

Amazon deforestation has declined over the last decade, yet forest degradation from logging, fire, and fragmentation continue to impact forest carbon stocks and fluxes. The magnitude of this impact remains uncertain, and observation-based studies are often limited by short time intervals or small study areas. To better understand the long-term impact of forest degradation and recovery, we have been developing a framework that integrates field plot measurements and airborne lidar surveys into an individual- and process-based model (Ecosystem Demography model, ED). We modeled forest dynamics for three forest landscapes in the Amazon with diverse degradation histories: conventional and reduced-impact logging, logging and burning, and multiple burns. Based on the initialization with contemporary forest structure and composition, model results suggest that degraded forests rapidly recover (30 years) water and energy fluxes compared with old-growth, even at sites that were affected by multiple fires. However, degraded forests maintained different carbon stocks and fluxes even after 100 years without further disturbances, because of persistent differences in forest structure and composition. Recurrent disturbances may hinder the recovery of degraded forests. Simulations using a simple fire model entirely dependent on environmental controls indicate that the most degraded forests would take much longer to reach biomass typical of old-growth forests, because drier conditions near the ground make subsequent fires more intense and more recurrent. Fires in tropical forests are also closely related to nearby human activities; while results suggest an important feedback between fires and the microenvironment, additional work is needed to improve how the model represents the human impact on current and future fire regimes. Our study highlights that recovery of degraded forests may act as an important carbon sink, but efficient recovery depends on controlling future disturbances.

The changing role of fire in mediating the relationships among oaks, grasslands, mesic temperate forests, and boreal forests in the Lake States

Treesearch

Lee E. Frelich; Peter B. Reich; David W. Peterson

2017-01-01

Historically, oak forests and woodlands intergraded with southern boreal forest, temperate mesic forest, and grassland biomes, forming complex fire-mediated relationships in the Great Lakes region of Minnesota, Wisconsin, and Michigan, USA. Variability in fire recurrence intervals allowed oaks to mix with grasses or with mesic forest species in areas with high (2–10 yr...

Soils of Mountainous Forests and Their Transformation under the Impact of Fires in Baikal Region

NASA Astrophysics Data System (ADS)

Krasnoshchekov, Yu. N.

2018-04-01

Data on postpyrogenic dynamics of soils under mountainous taiga cedar ( Pinus sibirica) and pine ( Pinus sylvestris) forests and subtaiga-forest-steppe pine ( Pinus sylvestris) forests in the Baikal region are analyzed. Ground litter-humus fires predominating in this region transform the upper diagnostic organic soil horizons and lead to the formation of new pyrogenic organic horizons (Opir). Adverse effects of ground fires on the stock, fractional composition, and water-physical properties of forest litters are shown. Some quantitative parameters of the liquid and solid surface runoff in burnt areas related to the slope gradient, fire intensity, and the time passed after the fire are presented. Pyrogenic destruction of forest ecosystems inevitably induces the degradation of mountainous soils, whose restoration after fires takes tens of years. The products of soil erosion from the burnt out areas complicate the current situation with the pollution of coastal waters of Lake Baikal.

Impacts of forest harvest on active carbon and microbial properties of a volcanic ash cap soil in northern Idaho

Treesearch

Deborah S. Page-Dumroese; Matt D. Busse; Steven T. Overby; Brian D. Gardner; Joanne M. Tirocke

2015-01-01

Soil quality assessments are essential for determining impacts on belowground microbial community structure and function. We evaluated the suitability of active carbon (C), a rapid field test, as an indicator of soil biological quality in five paired forest stands (clear cut harvested 40 years prior and unharvested) growing on volcanic ash-cap soils in northern Idaho....

Quantifying Fire's Impacts on Total and Pyrogenic Carbon Stocks in Mixed-Conifer Forests: Results from Pre- and Post-Fire Measurements in Active Wildfire Incidents

NASA Astrophysics Data System (ADS)

Miesel, J. R.; Reiner, A. L.; Ewell, C. M.; Sanderman, J.; Maestrini, B.; Adkins, J.

2016-12-01

Widespread US fire suppression policy has contributed to an accumulation of vegetation in many western forests relative to historic conditions, and these changes can exacerbate wildfire severity and carbon (C) emissions. Serious concern exists about positive feedbacks between wildfire emissions and global climate; however, fires not only release C from terrestrial to atmospheric pools, they also create "black" or pyrogenic C (PyC) which contributes to longer-term C stability. Our objective was to quantify wildfire impacts on aboveground and belowground total C and PyC stocks in California mixed-conifer forests. We worked with incident management teams to access five active wildfires to establish and measure plots within days before and after fire. We measured pre- and post-fire aboveground forest structure and woody fuels to calculate aboveground biomass, biomass C, and PyC, and we collected pre- and post-fire forest floor and 0-5 cm mineral soil samples to measure belowground C and PyC stocks. Our preliminary results show that fire had minimal impact on the number of trees per hectare, whereas C losses from the tree layer occurred via consumption of foliage, and PyC gain occurred in tree bark. Fire released 54% to 100% of surface fuel C. In the forest floor layer, we observed 33 to 100% C loss, whereas changes in PyC stocks ranged from 100% loss to 186% gain relative to pre-fire samples. In general, fire had minimal to no impact on 0-5 cm mineral soil C. We will present relationships between total C, PyC and post-fire C and N dynamics in one of the five wildfire sites. Our data are unique because they represent nearly immediate pre- and post-fire measurements in major wildfires in a widespread western U.S. forest type. This research advances understanding of the role of fire on forest C fluxes and C sequestration potential as PyC.

Predicting Fire Susceptibility in the Forests of Amazonia

NASA Technical Reports Server (NTRS)

Nepstad, Daniel C.; Brown, I. Foster; Setzer, Alberto

2000-01-01

Although fire is the single greatest threat to the ecological integrity of Amazon forests, our ability to predict the occurrence of Amazon forest fires is rudimentary. Part of the difficulty encountered in making such predictions is the remarkable capacity of Amazon forests to tolerate drought by tapping moisture stored in deep soil. These forests can avoid drought-induced leaf shedding by withdrawing moisture to depths of 8 meters and more. Hence, the absorption of deep soil moisture allows these forests to maintain their leaf canopies following droughts of several months duration, thereby maintaining the deep shade and high relative humidity of the forest interior that prevents these ecosystems from burning. But the drought- and fire-avoidance that is conferred by this deep-rooting phenomenon is not unlimited. During successive years of drought, such as those provoked by El Nino episodes, deep soil moisture can be depleted, and drought-induced leaf shedding begins. The goal of this project was to incorporate this knowledge of Amazon forest fire ecology into a predictive model of forest flammability.

Wildfire, Fuels Reduction, and Herpetofaunas across Diverse Landscape Mosaics in Northwestern Forests

USGS Publications Warehouse

Bury, R. Bruce

2004-01-01

The herpetofauna (amphibians and reptiles) of northwestern forests (U.S.A.) is diverse, and many species are locally abundant. Most forest amphibians west of the Cascade Mountain crest are associated with cool, cascading streams or coarse woody material on the forest floor, which are characteristics of mature forests. Extensive loss and fragmentation of habitat resulted from logging across approximately 50% of old-growth forests in northern California and approximately 80% of stands in Oregon and Washington. There is a complex landscape mosaic and overlap of northern and southern biotic elements in the Klamath-Siskiyou Region along the Oregon and California border, creating a biodiversity hotspot. The region experiences many low-severity fires annually, punctuated by periodic major fires, including the Biscuit fire, the largest in North America in 2002. In the fire's northern portion, severe fire occurred on >50% of stands of young, managed trees but on only about 25a??33% of old-growth stands. This suggests that the legacy of timber harvest may produce fire-prone stands. Calls for prescribed fire and thinning to reduce fuel loads will remove large amounts of coarse woody material from forests, which reduces cover for amphibians and alters nutrient inputs to streams. Our preliminary evidence suggests no negative effects of wildfire on terrestrial amphibians, but stream amphibians decrease following wildfire. Most reptiles are adapted to open terrain, so fire usually improves their habitat. Today, the challenge is to maintain biodiversity in western forests in the face of intense political pressures designed to 'prevent' catastrophic fires. We need a dedicated research effort to understanding how fire affects biota and to proactively investigate outcomes of fuel-reduction management on wildlife in western forests.

Decreases in Soil Moisture and Organic Matter Quality Suppress Microbial Decomposition Following a Boreal Forest Fire

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holden, Sandra R.; Berhe, Asmeret A.; Treseder, Kathleen K.

Climate warming is projected to increase the frequency and severity of wildfires in boreal forests, and increased wildfire activity may alter the large soil carbon (C) stocks in boreal forests. Changes in boreal soil C stocks that result from increased wildfire activity will be regulated in part by the response of microbial decomposition to fire, but post-fire changes in microbial decomposition are poorly understood. Here, we investigate the response of microbial decomposition to a boreal forest fire in interior Alaska and test the mechanisms that control post-fire changes in microbial decomposition. We used a reciprocal transplant between a recently burnedmore » boreal forest stand and a late successional boreal forest stand to test how post-fire changes in abiotic conditions, soil organic matter (SOM) composition, and soil microbial communities influence microbial decomposition. We found that SOM decomposing at the burned site lost 30.9% less mass over two years than SOM decomposing at the unburned site, indicating that post-fire changes in abiotic conditions suppress microbial decomposition. Our results suggest that moisture availability is one abiotic factor that constrains microbial decomposition in recently burned forests. In addition, we observed that burned SOM decomposed more slowly than unburned SOM, but the exact nature of SOM changes in the recently burned stand are unclear. Finally, we found no evidence that post-fire changes in soil microbial community composition significantly affect decomposition. Taken together, our study has demonstrated that boreal forest fires can suppress microbial decomposition due to post-fire changes in abiotic factors and the composition of SOM. Models that predict the consequences of increased wildfires for C storage in boreal forests may increase their predictive power by incorporating the observed negative response of microbial decomposition to boreal wildfires.« less

Reintroducing fire into a ponderosa pine forest with and without cattle grazing: understory vegetation response

Treesearch

Becky K. Kerns; Michelle Buonopane; Walter G. Thies; Christine. Niwa

2011-01-01

Reestablishing historical fire regimes is a high priority for North American coniferous forests, particularly ponderosa pine (Pinus ponderosa) ecosystems. These forests are also used extensively for cattle (Bos spp.) grazing. Prescribed fires are being applied on or planned for millions of hectares of these forests to reduce...

Measuring forest-fire danger in northern Idaho

Treesearch

H. T. Gisborne

1928-01-01

In most of the forest regions of the United States the fire problem is the greatest forest problem. Wasteful methods of logging and lumbering may result in the loss of a large proportion of the remaining forest growth, but the land will usually produce a new crop of timber without undue delay, unless fire occurs.

Meta-analysis of avian and small-mammal response to fire severity and fire surrogate treatments in U.S. fire-prone forests.

PubMed

Fontaine, Joseph B; Kennedy, Patricia L

2012-07-01

Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. Recently, published literature examining wildlife response to fire and fire management has increased rapidly. However, none of this literature has been synthesized quantitatively, precluding assessment of consistent patterns of wildlife response among treatment types. Using meta-analysis, we examined the scientific literature on vertebrate demographic responses to burn severity (low/moderate, high), fire surrogates (forest thinning), and fire and fire surrogate combined treatments in the most extensively studied fire-prone, forested biome (forests of the United States). Effect sizes (magnitude of response) and their 95% confidence limits (response consistency) were estimated for each species-by-treatment combination with two or more observations. We found 41 studies of 119 bird and 17 small-mammal species that examined short-term responses (< or =4 years) to thinning, low/moderate- and high-severity fire, and thinning plus prescribed fire; data on other taxa and at longer time scales were too sparse to permit quantitative assessment. At the stand scale (<50 ha), thinning and low/moderate-severity fire demonstrated similar response patterns in these forests. Combined thinning plus prescribed fire produced a higher percentage of positive responses. High-severity fire provoked stronger responses, with a majority of species possessing higher or lower effect sizes relative to fires of lower severity. In the short term and at fine spatial scales, fire surrogate forest-thinning treatments appear to effectively mimic low/moderate-severity fire, whereas low/moderate-severity fire is not a substitute for high-severity fire. The varied response of taxa to each of the four conditions considered makes it clear that the full range of fire-based disturbances (or their surrogates) is necessary to maintain a full complement of vertebrate species, including fire-sensitive taxa. This is especially true for high-severity fire, where positive responses from many avian taxa suggest that this disturbance (either as wildfire or prescribed fire) should be included in management plans where it is consistent with historic fire regimes and where maintenance of regional vertebrate biodiversity is a goal.

A pilot study of mercury liberation and capture from coal-fired power plant fly ash.

PubMed

Li, Jin; Gao, Xiaobing; Goeckner, Bryna; Kollakowsky, Dave; Ramme, Bruce

2005-03-01

The coal-fired electric utility generation industry has been identified as the largest anthropogenic source of mercury (Hg) emissions in the United States. One of the promising techniques for Hg removal from flue gas is activated carbon injection (ACI). The aim of this project was to liberate Hg bound to fly ash and activated carbon after ACI and provide high-quality coal combustion products for use in construction materials. Both bench- and pilot-scale tests were conducted to liberate Hg using a thermal desorption process. The results indicated that up to 90% of the Hg could be liberated from the fly ash or fly-ash-and-activated-carbon mixture using a pilot-scale apparatus (air slide) at 538 degrees C with a very short retention time (less than 1 min). Scanning electron microscope (SEM) evaluation indicated no significant change in fly ash carbon particle morphology following the thermal treatment. Fly ash particles collected in the baghouse of the pilot-scale apparatus were smaller in size than those collected at the exit of the air slide. A similar trend was observed in carbon particles separated from the fly ash using froth flotation. The results of this study suggest a means for power plants to reduce the level of Hg in coal-combustion products and potentially recycle activated carbon while maintaining the resale value of fly ash. This technology is in the process of being patented.

Influence of weather factors on moisture content of light fuels in forests of the northern Rocky Mountains

Treesearch

George M. Jemison

1935-01-01

The necessity of forest-fire protection is generally recognized in the United Slates. The tremendous damage done by forest fires each year to valuable timber, watershed cover, forest range, wildlife, recreational facilities, and personal property has impressed upon the people the need for preventing and controlling forest fires so far as this is humanly possible.

Fire effects in southwestern forests: Proceedings of the Second La Mesa Fire symposium

USGS Publications Warehouse

Allen, Craig D.

1996-01-01

In 1977, the La Mesa Fire burned across 15,444 acres of ponderosa pine forests on the adjoining lands of Bandelier National Monument, the Santa Fe National Forest, and Los Alamos National Laboratory. Following this event, several fire effects studies were initiated. The 16 papers herein document longer-term knowledge gained about the ecological effects of the fire and about Southwestern fire ecology in general. The presentations are also designed to give resource managers practical information for managing fire in local landscapes. Studies presented range from fire histories and avifauna to geomorphology and arthropods.

Physical and Chemical Character of Fly Ash of Coal Fired Power Plant in Java

NASA Astrophysics Data System (ADS)

Triwulan; Priadana, K. A.; Ekaputri, J. J.; Bayuaji, R.

2017-11-01

Quality of fly ash is varying widely in the field, it depends on the combustion process and the quality of the basic ingredients, namely coal. It will affect the physical and mechanical properties of the concrete mixtures used. This study used 12 samples of fly ash. The physical and chemical properties and finesse modulus were analyzed. The fly ash was mixed with OPC (Ordinary Portland Cement) with the proportion of 20% fly ash and 80% OPC. The specimens were form with mortar dimension of 5cm x 5 cm. The test was affected by the correlation of fly ash fineness modulus to compressive strength, correlation density of fly ash to compressive strength, and correlation of carbon content to the compressive strength.

How New York State saved its ash

Treesearch

C.L. Holmes; M. Marquand; E.M. Toth

2017-01-01

Across the United States, forest communities are faced with the prospect of extirpation of Fraxinus (ash) species owing to mortality caused by invasion of the emerald ash borer (Agrilus planipennis). However, with the advancement of ex situ seed conservation practices, we have the opportunity to conserve the ecoregional-based...

Emerald ash borer modeling methods for future forest projections

Treesearch

Ryan D. Desantis; W. Keith Moser; Robert J. Jr. Hugett; Ruhong Li; David N. Wear; Patrick D. Miles

2012-01-01

The emerald ash borer (Agrilus planipennis Fairmaire; EAB) is a nonnative invasive insect that has caused considerable damage to ash (Fraxinus spp.) in North America. Unlike invasive organisms that can be mitigated, contained, controlled, or even eradicated, EAB continues to spread across North America. The loss of the North...

Dispersal of the emerald ash borer, Agrilus planipennis, in newly-colonized sites

Treesearch

Rodrigo J. Mercader; Andrew M. Siegert; Andrew M. Liebhold; Deborah G. McCullough

2009-01-01

Emerald ash borer Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive forest insect pest threatening more than 8 billion ash (Fraxinus spp.) trees in North America. Development of effective survey methods and strategies to slow the spread of A. planipennis requires an understanding of dispersal...

Evaluation of double-decker traps for emerald ash borer (Coleoptera:Buprestidae)

Treesearch

Therese M. Poland; Deborah G. McCullough; Andrea C. Anulewicz

2011-01-01

Improved detection tools are needed for the emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), an invasive forest insect from Asia that has killed millions of ash (Fraxinus spp.) trees in North America since its discovery in Michigan in 2002.We evaluated attraction of adult A. planipennis...

Developing attractants and trapping techniques for the emerald ash borer

Treesearch

Therese M. Poland; Peter de Groot; Gary Grant; Linda MacDonald; Deborah G. McCullough

2003-01-01

Shortly after the 2002 discovery of emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in southeastern Michigan and Windsor, Ontario, quarantines regulating the movement of ash logs, firewood, and nursery stock were established to reduce the risk of human-assisted spread of this exotic forest insect pest. Accurate...

A hierarchical fire frequency model to simulate temporal patterns of fire regimes in LANDIS

Treesearch

Jian Yang; Hong S. He; Eric J. Gustafson

2004-01-01

Fire disturbance has important ecological effects in many forest landscapes. Existing statistically based approaches can be used to examine the effects of a fire regime on forest landscape dynamics. Most examples of statistically based fire models divide a fire occurrence into two stages--fire ignition and fire initiation. However, the exponential and Weibull fire-...

The simulation of surface fire spread based on Rothermel model in windthrow area of Changbai Mountain (Jilin, China)

NASA Astrophysics Data System (ADS)

Yin, Hang; Jin, Hui; Zhao, Ying; Fan, Yuguang; Qin, Liwu; Chen, Qinghong; Huang, Liya; Jia, Xiang; Liu, Lijie; Dai, Yuhong; Xiao, Ying

2018-03-01

The forest-fire not only brings great loss to natural resources, but also destructs the ecosystem and reduces the soil fertility, causing some natural disasters as soil erosion and debris flow. However, due to the lack of the prognosis for forest fire spreading trend in forest fire fighting, it is difficult to formulate rational and effective fire-fighting scheme. In the event of forest fire, achieving accurate judgment to the fire behavior would greatly improve the fire-fighting efficiency, and reduce heavy losses caused by fire. Researches on forest fire spread simulation can effectively reduce the loss of disasters. The present study focused on the simulation of "29 May 2012" wildfire in windthrow area of Changbai Mountain. Basic data were retrieved from the "29 May 2012" wildfire and field survey. A self-development forest fire behavior simulated program based on Rothermel Model was used in the simulation. Kappa coefficient and Sørensen index were employed to evaluate the simulation accuracy. The results showed that: The perimeter of simulated burned area was 4.66 km, the area was 56.47 hm2 and the overlapped burned area was 33.68 hm2, and the estimated rate of fire spread was 0.259 m/s. Between the simulated fire and actual fire, the Kappa coefficient was 0.7398 and the Sørensen co-efficient was 0.7419. This proved the application of Rothermel model to conduct fire behavior simulation in windthrow meadow was feasible. It can achieve the goal of forecasting for the spread behavior in windthrow area of Changbai Mountain. Thus, our self-development program based on the Rothermel model can provide a effective forecast of fire spread, which will facilitate the fire suppression work.

Development of an ash particle deposition model considering build-up and removal mechanisms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kjell Strandstroem; Christian Muellera; Mikko Hupa

2007-12-15

Slagging and fouling on heat exchanger surfaces in power boilers fired with fossil fuels and fuel mixtures has a significant influence on boiler efficiency and availability. Mathematical modelling has long been considered a suitable method to assist boiler operators to determine optimized operating conditions for an existing furnace. The ultimate goal in ash deposition prediction is hereby the determination of the total amount of material deposited and hence the determination of the total reduction in efficiency. Depending on the fuels fired the total deposited mass is a combination of ash particle deposition and ash particle erosion due to non-sticky particles.more » The novel ash particle deposition model presented in this work considers deposition of sticky ash particles, cleansing of deposit by non-sticky sand particles and sticking of sand due to contact with sticky ash. The steady-state modelling results for the total amount of ash deposited on the deposition probe of an entrained flow reactor presented in this work agree well with the experimental data. Only at very high fractions of sand added as non-sticky material, a significant influence of the sand on the overall mass deposited was found. Since the model considers sticking of non-sticking sand due to contact with sticky ash, the fraction of sand deposited on the probe was especially studied. Using a correction factor to consider the influence of operating time on the steady-state simulations led to good agreement between simulations and experimental data. 12 refs., 10 figs.« less

Ash effects on the thermal conductivity of a mediterranean loam soil

NASA Astrophysics Data System (ADS)

Rubio, Carles; Pereira, Paulo; Ubeda, Xavier

2014-05-01

The purpose of this work is to explore the variability on the soil thermal conductivity for a burnt soil and assessing the effects of the ashes on the heat transfer when they were incorporated into the soil matrix. A set of 42 soil samples from the Montgrí massif experimental plot between surface and 5 cm depth was collected before and after the soil was burnt. A thermal characterization of the soil was carried out. For that a dry out curve was constructed, which presented the relationship between water content and thermal conductivity for both types of soil samples, burnt and non-burnt soil. The results shown changes in the heat pulse transfer, being more conductive the soil before to be burnt (0.378 W•m-1•C-1) than the soil after to be exposed to the fire (0.337 W•m-1•C-1). Indeed, on the whole of moisture scenarios the values of thermal conductivity decreased after soil was burnt. Another experimental concern was based on to observe the soil thermal behaviour when ash collected after fire was incorporated into the burnt soil matrix. In this case, soil thermal and soil hydrodynamic behaviour presented differences according to the type of ash. Soil mixed with fly ash showed higher thermal conductivity than soil mixed with bottom ash. To sum up; the soil thermal conductivity decreased when soil was burnt. On the other hand, soil thermal conductivity shown differences depending on the type of ash incorporated into the matrix. Fly ash transferred the heat pulse better than bottom ash.

Simulating the Effects of Fire on Forests in the Russian Far East: Integrating a Fire Danger Model and the FAREAST Forest Growth Model Across a Complex Landscape

NASA Astrophysics Data System (ADS)

Sherman, N. J.; Loboda, T.; Sun, G.; Shugart, H. H.; Csiszar, I.

2008-12-01

The remaining natural habitat of the critically endangered Amur tiger (Panthera tigris altaica) and Amur leopard (Panthera pardus orientalis) is a vast, biologically and topographically diverse area in the Russian Far East (RFE). Although wildland fire is a natural component of ecosystem functioning in the RFE, severe or repeated fires frequently re-set the process of forest succession, which may take centuries to return the affected forests to the pre-fire state and thus significantly alters habitat quality and long-term availability. The frequency of severe fire events has increased over the last 25 years, leading to irreversible modifications of some parts of the species' habitats. Moreover, fire regimes are expected to continue to change toward more frequent and severe events under the influence of climate change. Here we present an approach to developing capabilities for a comprehensive assessment of potential Amur tiger and leopard habitat availability throughout the 21st century by integrating regionally parameterized fire danger and forest growth models. The FAREAST model is an individual, gap-based model that simulates forest growth in a single location and demonstrates temporally explicit forest succession leading to mature forests. Including spatially explicit information on probabilities of fire occurrence at 1 km resolution developed from the regionally specific remotely -sensed data-driven fire danger model improves our ability to provide realistic long-term projections of potential forest composition in the RFE. This work presents the first attempt to merge the FAREAST model with a fire disturbance model, to validate its outputs across a large region, and to compare it to remotely-sensed data products as well as in situ assessments of forest structure. We ran the FAREAST model at 1,000 randomly selected points within forested areas in the RFE. At each point, the model was calibrated for temperature, precipitation, slope, elevation, and fire probability. The output of the model includes biomass estimates for 44 tree species that occur in the RFE, grouped by genus. We compared the model outputs with land cover classifications derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) data and LIDAR-based estimates of biomass across the entire region, and Russian forest inventory records at selected sites. Overall, we find that the FAREAST estimates of forest biomass and general composition are consistent with the observed distribution of forest types.

Contrasting Spatial Patterns in Active-Fire and Fire-Suppressed Mediterranean Climate Old-Growth Mixed Conifer Forests

PubMed Central

Fry, Danny L.; Stephens, Scott L.; Collins, Brandon M.; North, Malcolm P.; Franco-Vizcaíno, Ernesto; Gill, Samantha J.

2014-01-01

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha−1, and occupied 27–46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11–20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥56%) in large patches (≥10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types. PMID:24586472

Automated Burned Area Delineation Using IRS AWiFS satellite data

NASA Astrophysics Data System (ADS)

Singhal, J.; Kiranchand, T. R.; Rajashekar, G.; Jha, C. S.

2014-12-01

India is endowed with a rich forest cover. Over 21% of country's area is covered by forest of varied composition and structure. Out of 67.5 million ha of Indian forests, about 55% of the forest cover is being subjected to fires each year, causing an economic loss of over 440 crores of rupees apart from other ecological effects. Studies carried out by Forest Survey of India reveals that on an average 53% forest cover of the country is prone to fires and 6.17% of the forests are prone to severe fire damage. Forest Survey of India in a countrywide study in 1995 estimated that about 1.45 million hectares of forest are affected by fire annually. According to Forest Protection Division of the Ministry of Environment and Forest (GOI), 3.73 million ha of forests are affected by fire annually in India. Karnataka is one of the southern states of India extending in between latitude 110 30' and 180 25' and longitudes 740 10' and 780 35'. As per Forest Survey of India's State of Forest Report (SFR) 2009, of the total geographic area of 191791sq.km, the state harbors 38284 sq.km of recorded forest area. Major forest types occurring in the study area are tropical evergreen and semi-evergreen, tropical moist and dry deciduous forests along with tropical scrub and dry grasslands. Typical forest fire season in the study area is from February-May with a peak during March-April every year, though sporadic fire episodes occur in other parts of the year sq.km, the state harbors 38284 sq.km of recorded forest area. Major forest types occurring in the study area are tropical evergreen and semi-evergreen, tropical moist and dry deciduous forests along with tropical scrub and dry grasslands. Significant area of the deciduous forests, scrub and grasslands is prone to recurrent forest fires every year. In this study we evaluate the feasibility of burned area mapping over a large area (Karnataka state, India) using a semi-automated detection algorithm applied to medium resolution multi spectral data from the IRS AWiFS sensor. The method is intended to be used by non-specialist users for diagnostic rapid burnt area mapping.

Measuring short-term post-fire forest recovery across a burn severity gradient in a mixed pine-oak forest using multi-sensor remote sensing techniques

DOE PAGES

Meng, Ran; Wu, Jin; Zhao, Feng; ...

2018-06-01

Understanding post-fire forest recovery is pivotal to the study of forest dynamics and global carbon cycle. Field-based studies indicated a convex response of forest recovery rate to burn severity at the individual tree level, related with fire-induced tree mortality; however, these findings were constrained in spatial/temporal extents, while not detectable by traditional optical remote sensing studies, largely attributing to the contaminated effect from understory recovery. For this work, we examined whether the combined use of multi-sensor remote sensing techniques (i.e., 1m simultaneous airborne imaging spectroscopy and LiDAR and 2m satellite multi-spectral imagery) to separate canopy recovery from understory recovery wouldmore » enable to quantify post-fire forest recovery rate spanning a large gradient in burn severity over large-scales. Our study was conducted in a mixed pine-oak forest in Long Island, NY, three years after a top-killing fire. Our studies remotely detected an initial increase and then decline of forest recovery rate to burn severity across the burned area, with a maximum canopy area-based recovery rate of 10% per year at moderate forest burn severity class. More intriguingly, such remotely detected convex relationships also held at species level, with pine trees being more resilient to high burn severity and having a higher maximum recovery rate (12% per year) than oak trees (4% per year). These results are one of the first quantitative evidences showing the effects of fire adaptive strategies on post-fire forest recovery, derived from relatively large spatial-temporal domains. Our study thus provides the methodological advance to link multi-sensor remote sensing techniques to monitor forest dynamics in a spatially explicit manner over large-scales, with important implications for fire-related forest management, and for constraining/benchmarking fire effect schemes in ecological process models.« less

Measuring short-term post-fire forest recovery across a burn severity gradient in a mixed pine-oak forest using multi-sensor remote sensing techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meng, Ran; Wu, Jin; Zhao, Feng

Understanding post-fire forest recovery is pivotal to the study of forest dynamics and global carbon cycle. Field-based studies indicated a convex response of forest recovery rate to burn severity at the individual tree level, related with fire-induced tree mortality; however, these findings were constrained in spatial/temporal extents, while not detectable by traditional optical remote sensing studies, largely attributing to the contaminated effect from understory recovery. For this work, we examined whether the combined use of multi-sensor remote sensing techniques (i.e., 1m simultaneous airborne imaging spectroscopy and LiDAR and 2m satellite multi-spectral imagery) to separate canopy recovery from understory recovery wouldmore » enable to quantify post-fire forest recovery rate spanning a large gradient in burn severity over large-scales. Our study was conducted in a mixed pine-oak forest in Long Island, NY, three years after a top-killing fire. Our studies remotely detected an initial increase and then decline of forest recovery rate to burn severity across the burned area, with a maximum canopy area-based recovery rate of 10% per year at moderate forest burn severity class. More intriguingly, such remotely detected convex relationships also held at species level, with pine trees being more resilient to high burn severity and having a higher maximum recovery rate (12% per year) than oak trees (4% per year). These results are one of the first quantitative evidences showing the effects of fire adaptive strategies on post-fire forest recovery, derived from relatively large spatial-temporal domains. Our study thus provides the methodological advance to link multi-sensor remote sensing techniques to monitor forest dynamics in a spatially explicit manner over large-scales, with important implications for fire-related forest management, and for constraining/benchmarking fire effect schemes in ecological process models.« less

Simulating the effect of ignition source type on forest fire statistics

NASA Astrophysics Data System (ADS)

Krenn, Roland; Hergarten, Stefan

2010-05-01

Forest fires belong to the most frightening natural hazards, and have long-term ecological and economic effects on the regions involved. It was found that their frequency-area distributions show power-law behaviour under a wide variety of conditions, interpreting them as a self-organised critical phenomenon. Using computer simulations, self-organised critical behaviour manifests in simple cellular automaton models. With respect to ignition source, forest fires can be categorised as lightning-induced or as a result of human activity. Lightning fires are considered to be natural, whereas ``man made'' fires are frequently caused by some sort of technological disaster, such as sparks from wheels of trains, the rupture of overhead electrical lines, the misuse of electrical or mechanical devices and so on. Taking into account that such events rarely occur deep in the woods, man made fires should start preferably on the edge of a forest or where the forest is not very dense. We present a modification in the self-organised critical Drossel-Schwabl forest fire model that takes these two different triggering mechanisms into account and increases the scaling exponent of the frequency-area distribution by ca. 1/3. Combined simulations further predict a dependence of the overall event-size distribution on the ratio of lightning-induced and man made fires as well as a splitting of their partial distributions. Lightning is identified as the dominant mechanism in the regime of the largest fires. The results are confirmed by the analysis of the Canadian Large Fire Database and suggest that lightning-induced and man made forest fires cannot be treated separately in wildfire modelling, hazard assessment and forest management.

Influence of Mortality Factors and Host Resistance on the Population Dynamics of Emerald Ash Borer (Coleoptera: Buprestidae) in Urban Forests.

PubMed

Macquarrie, Chris J K; Scharbach, Roger

2015-02-01

The success of emerald ash borer (Agrilus planipennis Fairmaire) in North America is hypothesized to be due to both the lack of significant natural enemies permitting easy establishment and a population of trees that lack the ability to defend themselves, which allows populations to grow unchecked. Since its discovery in 2002, a number of studies have examined mortality factors of the insect in forests, but none have examined the role of natural enemies and other mortality agents in the urban forest. This is significant because it is in the urban forest where the emerald ash borer has had the most significant economic impacts. We studied populations in urban forests in three municipalities in Ontario, Canada, between 2010 and 2012 using life tables and stage-specific survivorship to analyze data from a split-rearing manipulative experiment. We found that there was little overall mortality caused by natural enemies; most mortality we did observe was caused by disease. Stage-specific survivorship was lowest in small and large larvae, supporting previous observations of high mortality in these two stages. We also used our data to test the hypothesis that mortality and density in emerald ash borer are linked. Our results support the prediction of a negative relationship between mortality and density. However, the relationship varies between insects developing in the crown and those in the trunk of the tree. This relationship was significant because when incorporated with previous findings, it suggests a mechanism and hypothesis to explain the outbreak dynamics of the emerald ash borer. © The Author 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Cost-effective fire management for southern California's chaparral wilderness: an analytical procedure

Treesearch

Chris A. Childers; Douglas D. Piirto

1989-01-01

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management...

Effect of wildfires on physicochemical changes of watershed dissolved organic matter.

PubMed

Revchuk, Alex D; Suffet, I H

2014-04-01

Physicochemical characterization of dissolved organic carbon (DOC) provides essential data to describe watershed characteristics after drastic changes caused by wildfires. Post-fire watershed behavior is important for water source selection, management, and drinking water treatment optimization. Using ash and other burned vegetation fragments, a leaching procedure was implemented to describe physicochemical changes to watershed DOC caused by wildfires. Samples were collected after the 2007 and 2009 wildfires near Santa Barbara, California. Substantial differences in size distribution (measured by ultrafiltration), polarity (measured by polarity rapid assessment method), and the origin of leached DOC (measured by fluorescence) were observed between burned and unburned sites. Recently burned ash had 10 times the DOC leaching potential, and was dominated by large size fragments, compared to weathered 2-year-old ash. Charged DOC fractions were found to positively correlate with DOC size, whereas hydrophobic and hydrophilic DOC fractions were not. Proteins were only observed in recently burned ash and were indicative of recent post-fire biological activity.

Market assessment of PFBC ash use

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bland, A. E.; Brown, T. H., Western Research Institute

1998-01-01

Pressurized fluidized bed combustion (PFBC) of coal is undergoing demonstration in the United States, as well as throughout the world. American Electric Power`s (AEP`s) bubbling PFBC 70 MWe Tidd demonstration program in Ohio and pilot-scale development at Foster Wheeler Energia Oy 10 MWth circulating PFBC at Karhula, Finland, have demonstrated the advantages of PFBC technology. Further technology development in the US is planned with the deployment of the technology at the MacIntosh Clean Coal project in Lakeland, Florida. Development of uses for solid wastes from PFBC coal-fired power systems is being actively pursued as part of the demonstration of PFBCmore » technologies. Ashes collected from Foster Wheeler Energia Oy pilot circulating PFBC tests in Karhula, Finland, operating on (1) low sulfur subbituminous and (2) high sulfur bituminous coal; and ash from the AEP`s high-sulfur bituminous coal-fired bubbling PFBC in Brilliant, Ohio, were evaluated in laboratory and pilot-scale ash use testing at Western Research Institute (WRI).« less