Burned area mapping is an essential step in the forest fire research to investigate the relationship between forest fire and climate change and the effect of forest fire on carbon budgets. This study proposed an algor...Burned area mapping is an essential step in the forest fire research to investigate the relationship between forest fire and climate change and the effect of forest fire on carbon budgets. This study proposed an algorithm to map forest fire burned area using the Moderate-Resolution Imaging Spectroradiameter (MODIS) time series data in Heilongjiang Province, China. The algorithm is divided into two steps: Firstly, the′core′pixels were extracted to represent the most possible burned pixels based on the comparison of the temporal change of Global Environmental Monitoring Index (GEMI), Burned Area Index (BAI) and MODIS active fire products between pre- and post-fires. Secondly, a 15-km distance was set to extract the entire burned areas near the′core′pixels as more relaxed conditions were used to identify the fire pixels for reducing the omission error as much as possible. The algorithm comprehensively considered the thermal characteristics and the spectral change between pre-and post-fires, which are represented by the MODIS fire products and the spectral index, respectively. Tahe, Mohe and Huma counties of Heilongjiang Province, China were chosen as the study area for burned area mapping and a time series of burned maps were produced from 2000 to 2011. The results show that the algorithm展开更多
The severity of an initial burn injury is critical for determining the treatment plan and prognosis of burn patients. Here, we measured serum neutrophil gelatinase-associated lipocalin (NGAL) levels to determine wheth...The severity of an initial burn injury is critical for determining the treatment plan and prognosis of burn patients. Here, we measured serum neutrophil gelatinase-associated lipocalin (NGAL) levels to determine whether NGAL can be used as a biomarker for severity of burn injuries. A study of the demographic, clinical, and laboratory markers for various organ damage was performed at Bestian Burn Center (n = 10 healthy people, n = 31 patients). NGAL and organ damage marker levels were measured in 31 patients with severe burns within 2 - 3 days following their admission to the intensive care unit. Serum NGAL level of the expired patients was 788.5 (685.0 - 998.0) pg/mL, whereas that of the discharged patients was 421.2 (356.2 - 480.6) pg/mL, showing that the initial serum NGAL level can be used to estimate mortality. We also determined the correlation between serum NGAL level and the currently used severity markers (total body surface area burned and abbreviated burn severity index) and confirmed that serum NGAL level could be used as a severity marker. We also found that serum NGAL level was correlated with damage of organs such as the liver, kidney, heart, and respiratory organs in patients with severe burns.展开更多
This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),...This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),and climate variables such as temperature,wind speed,relative humidity,and volumetric soil moisture from the ERA5 reanalysis dataset were used.Pearson correlation coefficient was used to determine the relationship between biophysical and climate variables and fire occurrence.The results show that FBA increased by 1.7 hectares/decade from 2001 to 2020.The high FBA in 2010(the black summer of Iran)was due to high temperatures and significant heatwaves that led to extensive wildfires.Although anthropogenic activities are considered a significant cause of wildfires,several variables,including increased temperatures,less precipitation,relative humidity,and wind speed and direction,contribute to the extent and occurrence of wildfires.The country’s FBA hotspot is in the Arasbaran region during the summer season.Temperature and relative humidity are the most significant variables influencing the occurrence of wildfires.The results show the vulnerability of Iran s forests and their high potential for fires.Considering the frequency of fire occurrences in Iran and the limited equipment,fire prevention plans should be carried out by applying proper management in high-risk regions.展开更多
秸秆露天焚烧是农业生产的主要碳排放活动。为全面掌握秸秆露天焚烧的时空分布,准确获取秸秆露天焚烧的碳排放量,以2014-2020年Satellite See Fire数据为数据源,提取呼和浩特市的秸秆火点,分析其数量的年际、月际和区域变化规律;基于202...秸秆露天焚烧是农业生产的主要碳排放活动。为全面掌握秸秆露天焚烧的时空分布,准确获取秸秆露天焚烧的碳排放量,以2014-2020年Satellite See Fire数据为数据源,提取呼和浩特市的秸秆火点,分析其数量的年际、月际和区域变化规律;基于2020年Sentinel-2遥感影像,使用归一化燃烧指数(NBR)、燃烧面积指数(BAI)以及改进的燃烧指数(NBRSWIR11、BAI_(Red Edge5)、BAI_(Red Edge6)、BAI_(Red Edge7))提取研究区主要月份的火烧迹地,通过筛选燃烧指数、确定估算阈值,进而得到秸秆露天焚烧的碳排放量。结果表明:2014-2020年呼和浩特市秸秆火点主要集中在土默特左旗、托克托县、和林格尔县以及市区南部,火点数量整体呈下降趋势;春季(3、4月)和秋季(10、11月)为秸秆露天焚烧的主要月份,其中3、10、11月提取火烧迹地的最佳燃烧指数和阈值分别为BAI和78、120与110,4月提取火烧迹地的最佳燃烧指数和阈值分别为BAIRed Edg e5和78;2020年秸秆露天焚烧面积为16万hm^(2),秸秆露天焚烧总量为114.8万t,CH4、CO、CO_(2)和碳排放总量分别为0.25万t、11.73万t、159.62万t和48.75万t。展开更多
基金Under the auspices of Strategic Pilot Science and Technology Projects of Chinese Academic Sciences(No.XDA05090310)
文摘Burned area mapping is an essential step in the forest fire research to investigate the relationship between forest fire and climate change and the effect of forest fire on carbon budgets. This study proposed an algorithm to map forest fire burned area using the Moderate-Resolution Imaging Spectroradiameter (MODIS) time series data in Heilongjiang Province, China. The algorithm is divided into two steps: Firstly, the′core′pixels were extracted to represent the most possible burned pixels based on the comparison of the temporal change of Global Environmental Monitoring Index (GEMI), Burned Area Index (BAI) and MODIS active fire products between pre- and post-fires. Secondly, a 15-km distance was set to extract the entire burned areas near the′core′pixels as more relaxed conditions were used to identify the fire pixels for reducing the omission error as much as possible. The algorithm comprehensively considered the thermal characteristics and the spectral change between pre-and post-fires, which are represented by the MODIS fire products and the spectral index, respectively. Tahe, Mohe and Huma counties of Heilongjiang Province, China were chosen as the study area for burned area mapping and a time series of burned maps were produced from 2000 to 2011. The results show that the algorithm
文摘The severity of an initial burn injury is critical for determining the treatment plan and prognosis of burn patients. Here, we measured serum neutrophil gelatinase-associated lipocalin (NGAL) levels to determine whether NGAL can be used as a biomarker for severity of burn injuries. A study of the demographic, clinical, and laboratory markers for various organ damage was performed at Bestian Burn Center (n = 10 healthy people, n = 31 patients). NGAL and organ damage marker levels were measured in 31 patients with severe burns within 2 - 3 days following their admission to the intensive care unit. Serum NGAL level of the expired patients was 788.5 (685.0 - 998.0) pg/mL, whereas that of the discharged patients was 421.2 (356.2 - 480.6) pg/mL, showing that the initial serum NGAL level can be used to estimate mortality. We also determined the correlation between serum NGAL level and the currently used severity markers (total body surface area burned and abbreviated burn severity index) and confirmed that serum NGAL level could be used as a severity marker. We also found that serum NGAL level was correlated with damage of organs such as the liver, kidney, heart, and respiratory organs in patients with severe burns.
基金supported by a grant from Shahid Beheshti University。
文摘This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),and climate variables such as temperature,wind speed,relative humidity,and volumetric soil moisture from the ERA5 reanalysis dataset were used.Pearson correlation coefficient was used to determine the relationship between biophysical and climate variables and fire occurrence.The results show that FBA increased by 1.7 hectares/decade from 2001 to 2020.The high FBA in 2010(the black summer of Iran)was due to high temperatures and significant heatwaves that led to extensive wildfires.Although anthropogenic activities are considered a significant cause of wildfires,several variables,including increased temperatures,less precipitation,relative humidity,and wind speed and direction,contribute to the extent and occurrence of wildfires.The country’s FBA hotspot is in the Arasbaran region during the summer season.Temperature and relative humidity are the most significant variables influencing the occurrence of wildfires.The results show the vulnerability of Iran s forests and their high potential for fires.Considering the frequency of fire occurrences in Iran and the limited equipment,fire prevention plans should be carried out by applying proper management in high-risk regions.
