Integration of socio-economic and environmental variables for modelling long-term fire danger in Southern Europe

2007 ◽  
Vol 127 (2) ◽  
pp. 149-163 ◽  
Author(s):  
Ana Sebastián-López ◽  
Raymond Salvador-Civil ◽  
Julián Gonzalo-Jiménez ◽  
Jesús SanMiguel-Ayanz
Keyword(s):  
Environmental Variables ◽  
Fire Danger ◽  
Southern Europe

scholarly journals Remote Sensing Data for Calibrated Assessment of Wildfire Emissions in Siberian Forests

Proceedings ◽  
2018 ◽  
Vol 2 (7) ◽  
pp. 348
Author(s):  
Evgenii Ponomarev ◽  
Eugene Shvetsov ◽  
Kirill Litvintsev ◽  
Irina Bezkorovaynaya ◽  
Tatiana Ponomareva ◽  
...  
Keyword(s):  
Standard Procedure ◽  
Remote Sensing Data ◽  
Fire Danger ◽  
Variable Intensity ◽  
Burned Areas ◽  
Radiative Power ◽  
Terra Modis ◽  
Siberian Forests

This study was carried out for Siberia using Terra/Modis satellite data (2002–2016), data of ground surveys on burned areas of different ages, long-term meteorological information, and numerical simulation results. On the basis of meteorological and wildfire databases, we evaluated the probability (~18%) of an extreme fire danger scenario that was found to occur every 8 ± 3 years in different parts of the region. Next, we used Fire Radiative Power (FRP) measurements to classify the varieties of burning conditions for each wildfire in the database. The classification of the annually burned forest area was obtained in accordance with the assessments of burning intensity ranges categorized by FRP. Depending on the fire danger scenario in Siberia, 47.04 ± 13.6% of the total wildfire areas were classified as low-intensity burning, 42.46 ± 10.50% as medium-intensity fire areas, and 10.50 ± 6.90% as high-intensity. Next, we calculated the amount of combusted biomass and the direct emissions for each wildfire, taking into account the variable intensity of burning within the fire polygons. The total annual emissions were also calculated for Siberia for the last 15 years, from 2002 to 2016. The average estimate of direct carbon emission was 83 ± 21 Tg/year, which is lower than the result (112 ± 25 Tg/year) we obtained using the standard procedure.

scholarly journals Effects of Environmental Variables on some Physiological Responses of Microtus montanus Under Natural Conditions

1982 ◽  
Vol 6 ◽  
pp. 66-68
Author(s):  
Aelita Pinter
Keyword(s):  
Environmental Variables ◽  
National Park ◽  
Reproductive Activity ◽  
Natural Conditions ◽  
Term Study ◽  
Microtus Montanus ◽  
Long Term Study ◽  
Microtine Rodents ◽  
Different Seasons

Cyclic fluctations in the popu]ation density of rnicrotine rodents have been known since antiquity. However, factors responsible for this phenomenon are not known. The objectives of this long term study are essentially threefold: 1. characterize those environmental variables that might affect Microtus montanus in different seasons of the year; 2. record the growth, maturation and reproductive activity of the voles under natural conditions; and 3. determine the maturational, as well as, the seasonal pelage changes of these rodents. The data resulting from the execution of the above objectives would be correlated in an attempt to determine the causes undedying the multiannual fluctuations in the population density of these microtine rodents in Grand Teton National Park.

scholarly journals Long-term temporal changes in the occurrence of a high forest fire danger in Finland

2012 ◽  
Vol 12 (8) ◽  
pp. 2591-2601 ◽  
Author(s):  
H. M. Mäkelä ◽  
M. Laapas ◽  
A. Venäläinen
Keyword(s):  
Forest Fire ◽  
Forest Fires ◽  
Large Scale ◽  
Weather Conditions ◽  
Temporal Variations ◽  
Fire Danger ◽  
Specific Information ◽  
Climate Data ◽  
Forest Fire Danger

Abstract. Climate variation and change influence several ecosystem components including forest fires. To examine long-term temporal variations of forest fire danger, a fire danger day (FDD) model was developed. Using mean temperature and total precipitation of the Finnish wildfire season (June–August), the model describes the climatological preconditions of fire occurrence and gives the number of fire danger days during the same time period. The performance of the model varied between different regions in Finland being best in south and west. In the study period 1908–2011, the year-to-year variation of FDD was large and no significant increasing or decreasing tendencies could be found. Negative slopes of linear regression lines for FDD could be explained by the simultaneous, mostly not significant increases in precipitation. Years with the largest wildfires did not stand out from the FDD time series. This indicates that intra-seasonal variations of FDD enable occurrence of large-scale fires, despite the whole season's fire danger is on an average level. Based on available monthly climate data, it is possible to estimate the general fire conditions of a summer. However, more detailed input data about weather conditions, land use, prevailing forestry conventions and socio-economical factors would be needed to gain more specific information about a season's fire risk.

Combining management based indices with environmental parameters to explain regional variation in soil carbon under dryland cropping in South Australia

Soil Research ◽  
2013 ◽  
Vol 51 (8) ◽  
pp. 738 ◽  
Author(s):  
Lynne M. Macdonald ◽  
Tim Herrmann ◽  
Jeffrey A. Baldock
Keyword(s):  
Environmental Variables ◽  
Explanatory Power ◽  
Regional Scale ◽  
South Australia ◽  
Vapour Pressure Deficit ◽  
Environmental Parameters ◽  
Decomposition Processes ◽  
Historical Management ◽  
Broad Scale

Identifying drivers of variation in soil organic carbon (OC) at a regional scale is often hampered by a lack of historical management information. Focusing on red-brown-earth soils (Chromosol) under dryland agriculture in the Mid-North and Eyre Peninsula of South Australia, our aims were 2-fold: (i) to provide a baseline of soil OC stocks (0.3 m) and OC fractions (mid-infrared predictions of particulate, humus, and resistant OC in 0.1 m samples) in cropping and crop-pasture systems; and (ii) to evaluate whether the inclusion of management-based indices could assist in explaining regional-level variation in OC stocks and fractions. Soil OC stocks in both regions varied ~20 Mg ha–1, with higher OC stocks in the Mid-North (38 Mg ha–1) than the Eyre Peninsula (29.1 Mg ha–1). The humus OC fraction was the dominant fraction, while the particulate OC was the most variable. Environmental variables only partially explained soil OC variability, with vapour pressure deficit (VPD) offering the greatest potential and likely acting as an integrator of temperature and moisture on plant growth and decomposition processes. Differences between broad-scale cropping and crop–pasture systems were limited. In the Mid-North, variability in soil OC stocks and fractions was high, and could not be explained by environmental or management variables. Higher soil OC concentrations (0.1 m) in the Eyre Peninsula cropping than crop–pasture soils were largely accounted for in the particulate OC fraction and are therefore unlikely to represent a long-term stable OC pool. Use of the management data in index format added some explanatory power to the variability in OC stocks over the main environmental variables (VPD, slope) within the Eyre Peninsula cropping soils only. In the wider context, the management data were useful in interpreting differences between regional findings and highlighted difficulties in using uninformed, broad-scale management categories.

scholarly journals How relevant is the deposition of mercury onto snowpacks? – Part 1: A statistical study on the impact of environmental factors

2012 ◽  
Vol 12 (19) ◽  
pp. 9221-9249 ◽  
Author(s):  
D. A. Durnford ◽  
A. P. Dastoor ◽  
A. O. Steen ◽  
T. Berg ◽  
A. Ryzhkov ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Atmospheric Stability ◽  
Atmospheric Mercury ◽  
Aquatic Life ◽  
Confidence Levels ◽  
Environmental Controls ◽  
Surface Snow ◽  
Ionic Pulse ◽  
The Impact

Abstract. A portion of the highly toxic methylmercury that bioaccumulates in aquatic life is created from mercury entering bodies of water with snowpack meltwater. To determine the importance of meltwater as a source of aquatic mercury, it is necessary to understand the environmental processes that govern the behavior of snowpack-related mercury. In this study we investigate relationships among 5 types of snowpack-related mercury observations and 20 model environmental variables. The observation types are the 24-h fractional loss of mercury from surface snow, and the concentrations of mercury in surface snow, seasonal snowpacks, the snowpack meltwater's ionic pulse, and long-term snowpack-related records. The model environmental variables include those related to atmospheric mercury, insolation, wind, atmospheric stability, snowpack physical characteristics, atmospheric pressure, and solid precipitation. Bivariate and multiple linear regressions were performed twice for each mercury observation type: once with all observations, and once excluding observations from locations where the snowpack's burden of oxidizing and stabilizing halogens is known or presumed to affect snowpack mercury. Since no observations from long-term snowpack-related records were considered affected by halogens, this group of observations was included with the sets of uninfluenced observations and was not discussed with the complete, original sets of observations. When all observations are included, only 37% of their variability can be explained, on average, with significance confidence levels averaging 81%; a separate regression model predicts each mercury observation type. Without the influence of halogens, the regression models are able to explain an average of 79% of the observations' variability with significance confidence levels averaging 97%. The snowpack-related mercury observations are most strongly controlled by the dry and wet depositions of oxidized mercury, and by precipitation. Mercury deposited through wet processes is more strongly retained by snowpacks than mercury deposited through dry processes. Revolatilization of mercury deposited through wet processes may be inhibited through burial by fresh snowfalls and/or by its more central location, compared to that of mercury deposited through dry deposition, within snowpack snow grains. The two depositions of oxidized mercury together explain 84% of the variability in observed concentrations of mercury in surface snow, 52% of the variability of observed concentrations of mercury in seasonal snowpacks and their meltwater's ionic pulse, and only 20% of the variability of observed concentrations of mercury in long-term snowpack-related records; other environmental controls seemingly gain in relevance as time passes. The concentration of mercury in long-term records is apparently primarily affected by latitude; both the primary sources of anthropogenic mercury and the strong upper-level zonal winds are located in the midlatitudes.

Examination of Residuals to Vancouver Crisis Call Data by Using Hidden Markov Models

2002 ◽  
Vol 94 (2) ◽  
pp. 548-550
Author(s):  
W. H. Laverty ◽  
M. J. Miket ◽  
I. W. Kelly
Keyword(s):  
Regression Analysis ◽  
Hidden Markov Models ◽  
Environmental Variables ◽  
Markov Models ◽  
Hidden Markov ◽  
Linear Trend ◽  
Seasonal Trend ◽  
Best Fitting ◽  
Crisis Call

Three years of daily crisis calls ( N=2,513,478) were examined in a regression analysis with terms for effects for weekday, end and beginning of the month, holiday, seasonal trend, and long-term linear trend. This was followed by an analysis of residuals using hidden Markov models, with three states best fitting the residuals. These states may reflect economic or environmental variables which researchers should clarify in further work.

The role of environmental variables on interannual variation in species composition and biomass in a subtropical minerotrophic floating marsh

1995 ◽  
Vol 73 (3) ◽  
pp. 413-424 ◽  
Author(s):  
Charles E. Sasser ◽  
Jenneke M. Visser ◽  
D. Elaine Evers ◽  
James G. Gosselink
Keyword(s):  
Species Composition ◽  
Environmental Variables ◽  
Plant Biomass ◽  
Dry Weight ◽  
Individual Species ◽  
Panicum Hemitomon ◽  
Dominant Plant Species ◽  
Related Plant ◽  
Floating Marsh

Floating marshes supporting emergent vascular vegetation occur in expansive areas in many parts of the world. We analyzed the long-term variability in species composition and related plant biomass to environmental variables in a subtropical minerotrophic floating marsh, Louisiana, U.S.A. Panicum hemitomon was the dominant plant species, representing 76% of the total mean end of season aboveground dry weight of 840 g∙m−2. Multivariate analyses showed that community structure in the Lake Boeuf floating marsh has changed little during the 11 years included in this study. Individual species occurring in varying frequency with the dominant, Panicum hemitomon, form two marginally distinct assemblages. Mean live end of season biomass varied from a low of 602 g dry wt∙m−2 to a high of 1173 g dry wt∙m−2 during the period of the study. Ninety-nine percent of the variation in total aboveground biomass can be predicted by environmental variables related to temperature, precipitation, evaporation, and water level. Mapping of the area for the years 1945, 1952, 1981, and 1992 show that a net loss of about 4% of marsh has occurred between 1945 and 1992. Key words: vegetation, stability, freshwater floating marsh, Panicum hemitomon, Louisiana, climate.

scholarly journals Phytosociological Data in Assessment of Anthropogenic Changes in Vegetation of Rzeszów Reservoir

2021 ◽  
Vol 13 (16) ◽  
pp. 9071
Author(s):  
Maria Ziaja ◽  
Tomasz Wójcik ◽  
Małgorzata Wrzesień
Keyword(s):  
Environmental Variables ◽  
Vegetation Type ◽  
Plant Distribution ◽  
Vegetation Types ◽  
Ellenberg Indicator Values ◽  
Indicator Values ◽  
Marsh Vegetation ◽  
Se Poland ◽  
Main Factor

Phytosociological research on aquatic and marsh vegetation was conducted in Rzeszów Reservoir (SE Poland): 134 relevés according to the Braun-Blanquet method were collected there in 2016 and compared to 91 relevés published in 1994 (225 relevés in total). Changes in vegetation type, diversity measures, species composition, and Ellenberg Indicator Values (EIVs) for light, moisture, reaction, and nitrogen were analysed. Over the 22 years (1994–2016), the greatest changes were noted in communities of the classes Lemnetea and Potametea and the alliance Salicion albae. The long-term observations demonstrated the disappearance of 14 phytocoenoses and the occurrence of 12 new ones. An expansion of marsh communities (Typhetum latifoliae, Typhetum angustifoliae, Glycerietum maximae, Leersietum oryzoidis) was noted, causing a decline of several species and vegetation types. According to canonical correspondence analysis (CCA), four environmental variables (light, moisture, nitrogen, and pH) were related to plant distribution. The strong disturbances reflected in intensive eutrophication were due to human activity, which is the main factor shaping the ecological succession and overgrowing of the reservoir.

scholarly journals Effects of Environmental Variables on Some Physiological Responses of Microtus montanus under Natural Conditions

1984 ◽  
Vol 8 ◽  
pp. 69-70
Author(s):  
Aelita Pinter
Keyword(s):  
Population Density ◽  
Environmental Variables ◽  
Reproductive Activity ◽  
Natural Conditions ◽  
Term Study ◽  
Microtus Montanus ◽  
Long Term Study ◽  
Microtine Rodents ◽  
Different Seasons

Cyclic fluctuations in the population density of microtine rodents have been known since antiquity. However, factors responsible for this phenomenon are not known. The objectives of this long term study are essentially threefold. First, to characterize those environmental variables that might affect Microtus montanus in different seasons of the year. Second, to record the growth, maturation and reproductive activity of the voles under natural conditions. Third, to determine the maturational as well as the seasonal pelage changes of these rodents. The data resulting from the execution of the above objectives would be correlated in an attempt to determine the causes underlying the multiannual fluctuations in the population density of these microtine rodents in Grand Teton National Park.

Sign in / Sign up

Export Citation Format

Share Document