Study on Climate and Grassland Fire in HulunBuir, Inner Mongolia Autonomous Region, China

Abstract

Grassland fire is one of the most important disturbance factors of the natural ecosystem. Climate factors influence the occurrence and development of grassland fire. An analysis of the climate conditions of fire occurrence can form the basis for a study of the temporal and spatial variability of grassland fire. The purpose of this paper is to study the effects of monthly time scale climate factors on the occurrence of grassland fire in HulunBuir, located in the northeast of the Inner Mongolia Autonomous Region in China. Based on the logistic regression method, we used the moderate-resolution imaging spectroradiometer (MODIS) active fire data products named thermal anomalies/fire daily L3 Global 1km (MOD14A1 (Terra) and MYD14A1 (Aqua)) and associated climate data for HulunBuir from 2000 to 2010, and established the model of grassland fire climate index. The results showed that monthly maximum temperature, monthly sunshine hours and monthly average wind speed were all positively correlated with the fire climate index; monthly precipitation, monthly average temperature, monthly average relative humidity, monthly minimum relative humidity and the number of days with monthly precipitation greater than or equal to 5 mm were all negatively correlated with the fire climate index. We used the active fire data from 2011 to 2014 to validate the fire climate index during this time period, and the validation result was good (Pearson’s correlation coefficient was 0.578), which showed that the fire climate index model was suitable for analyzing the occurrence of grassland fire in HulunBuir. Analyses were conducted on the temporal and spatial distribution of the fire climate index from January to December in the years 2011–2014; it could be seen that from March to May and from September to October, the fire climate index was higher, and that the fire climate index of the other months is relatively low. The zones with higher fire climate index are mainly distributed in Xin Barag Youqi, Xin Barag Zuoqi, Zalantun Shi, Oroqen Zizhiqi, and Molidawa Zizhiqi; the zones with medium fire climate index are mainly distributed in Chen Barag Qi, Ewenkizu Zizhiqi, Manzhouli Shi, and Arun Qi; and the zones with lower fire climate index are mainly distributed in Genhe Shi, Ergun city, Yakeshi Shi, and Hailar Shi. The results of this study will contribute to the quantitative assessment and management of early warning and forecasting for mid-to long-term grassland fire risk in HulunBuir.

The Effect of Snow Depth on Spring Wildfires on the Hulunbuir from 2001–2018 Based on MODIS

“…The results of this study indicate that SWFs are mainly distributed in eastern Hulunbuir, which is consistent with previous studies [8,36,38]. Liu et al showed that grassland fires occur mainly in eastern Hulunbuir (with low occurrence in the other areas) based on the MODIS active fire product over the period of 2000-2014 [11]. This study showed that the land use patterns are quite different in the study area.…”

“…The results showed a strong negative correlation between SWFs and snow depth. Previous research has shown that temperature, precipitation, and relative humidity are the main meteorological factors that affect wildfire occurrence [8,11,55]. Snow has a different influence on the surface humidity and the LST after it enters the melting period, and the surface humidity and temperature are the main climatic factors influencing wildfires.…”

“…Hulunbuir is the easternmost prefecture-level city in IMC, and it is rich in grassland and forest resources. Statistical analyses show that from 1981 to 1999, a total of 892 grassland fires occurred in the eastern part of the IMC for an average of 46.95 fires per year, and the most frequent occurrence was in Hulunbuir [11,12]. Hulunbuir has less precipitation in spring and autumn, dry weather, and a high number of strong wind days, and most of the grassland and forest areas are relatively sparsely populated and have low traffic.…”

Wildfires on the Mongolian Plateau: Identifying Drivers and Spatial Distributions to Predict Wildfire Probability

“…The FVC changes with different seasons and within different time periods of the same season [26]. Meteorological factors mainly affect the occurrence of wildfire on a large scale [5,31], e.g., high temperatures and sunshine duration are variables that either alone or together can contribute to increased potential evaporation from fuels and decreased moisture of wildfire fuel, leading to an increased possibility of wildfire occurrence [34]. High precipitation and relative humidity contribute to fuel moisture, which in turn decreases the probability of wildfires [36].…”

“…Specifically, high-temperatures, low-temperature freezing damage, uneven precipitation, continuous droughts in the spring and summer and other abnormal climatic phenomena are increasing [4]. As a result, the fire frequency and the duration of disturbances are increasing [5]. These changes affect the material cycles, energy flows, and information transmission of ecosystems.…”