Mapping fire regimes in China using MODIS active fire and burned area data

Relatively little is known about vegetation fire regimes in China. In this study, we investigated fire regime characteristics and their potential drivers, utilizing information extracted from the MODerate resolution Imaging Spectrometer (MODIS) satellite. Twelve fire regime variables were selected and computed on a regular grid over all of China, using MODIS burned area and active fire data during the period 2001 to 2016, to identify fire incidence and its inter-annual variability, seasonality, intensity, fire size distribution and vegetation types affected by fire. The variables were normalized and clustered to define six fire regimes with distinctive fire attributes. Results show that 78.6% of the land in China was affected by fire during the study period. The barren or sparsely vegetated lands of western China are nearly fire-free. Active fires were observed in Central China, but area burned was not detectable from MODIS. Forest fires in northeastern China are relatively large, infrequent, with a short fire season that peaks in non-winter seasons and higher inter-annual variability, implying a high likelihood of accidental causes. In contrast, forest fires in southern China are relatively small, frequent, with a long fire season that peaks in non-summer seasons, and lower inter-annual variability, suggesting regular use as a land management tool. Low inter-annual variability and low fire intensity were associated with cropland fires, whereas grassland fires generally exhibit the opposite traits. We have also discussed the potential drivers of each fire regime characteristics.     

Spatial and temporal patterns of fires in tropical savannas of Indonesia

This paper examines spatial and temporal patterns of large to medium‐sized fires across the Indonesian Archipelago using remote sensing, particularly the MODIS fire products, over a 14 years period (2000–13 inclusive) in conjunction with climatic and land data in a GIS. Results showed fires (burned area and number of fires) were detected the most in year 2002 and least in 2010. The extent of burning was correlated with the annual Southern Oscillation Index with most burning occurring during times of sustained negative SOI values, which generally means drier conditions across the region. Most of the detected fires occurred in the middle of the dry season and in drier eastern Indonesia. Across Indonesia, approximately 1.5 per cent of available open vegetation area burned, whereas only 0.5 per cent of forest area burned. Most open vegetation burning was detected in the savanna with an area equivalent to 11.1 per cent of its extent being burned over the 14 years. On Sumba Island, where the pronounced dry season extends for at least four months, open vegetation is the most common land cover type, of which 99 per cent burned by area over the study period making it the island with the most burned areas in the Indonesian Archipelago.     

The role of fire as a long-term landscape modifier: Evidence from long-term fire observations (1922–2000) in Greece

The objective of this paper is to document the role of fire in shaping the landscape by identifying links between historical fire records and the current landscape indicating that fire favors certain land use/land cover (LULC) types. We geo-referenced fire records taken from 1922 to 2000 in Aitoloakarnania, the largest prefecture -in terms of surface area- of Greece and compared the past LULC classes where fires burned to the present landscape. The outputs indicated a shift of the historic fire ignition points from natural to agricultural-related LULC classes since a significant proportion of fire incidents that, according to the fire records, burnt natural vegetation units is currently located in agricultural landscape units. Additionally, a significant proportion of the fire-affected land cover classes retain their character thus supporting the argument that these classes, especially fire-prone or fire-resistant, have developed mechanisms to cope with fire. In such ecosystems the role of fire is to maintain rather than transform land cover classes.The findings of this research lead us to conclude that fire can be perceived as a long-term landscape modifier in the Mediterranean, although its effects may vary from region to region because of differences in regeneration patterns among the main land cover types, topographic constraints and local fire histories. Historical fire records extending back to the early 20th century proved to provide valuable information that can reveal interesting patterns of fire burning history and explain present land cover and use patterns. This knowledge, documented from historical records, can be used to develop fire management and land cover/land use management planning.     

The environmental envelope of fires in the Colombian Caribbean

Fire is an important disturbance agent for terrestrial ecosystems, particularly in tropical and subtropical regions where its occurrence is controlled by multiple biophysical and anthropogenic variables. We assessed the temporal and spatial patterns of active fire detections (MODIS product MCD14ML) in the Caribbean region of Colombia between 2003 and 2015, using time series, cross-correlation, hot spot and density techniques. We also assessed the environmental envelope of active fires by evaluating the effect of multiple biophysical and anthropogenic variables on fire presence/absence using generalized linear models (GLMs). Results show that fires follow a clear intra-annual cycle, with 86% of fire events taking place during the region's main dry season (December–March). There is also inter-annual variability related to the Tropical North Atlantic (TNA) quasi-decadal climatic oscillation. Active fires exhibit a distinctive spatial pattern, with regional hotspots. The set of variables that best explain fire presence/absence include biophysical (TNA, temperature annual range, dry quarter precipitation), anthropogenic (minimum distance to towns and roads) and composite (NDVI) variables. The extensive and ongoing land cover transformation of this region, from forest to pasture and agriculture, will likely increase the extent of burned areas and future carbon fire emissions to the atmosphere.     

Remotely sensing the spatial and temporal land cover changes in Eastern Mau forest reserve and Lake Nakuru drainage basin,Kenya

This study aimed at characterizing land cover dynamics for four decades in Eastern Mau forest and Lake Nakuru basin, Kenya. The specific objectives were to: (i) identify and map the major land cover types in 1973, 1985, 2000 and 2011; (ii) detect and determine the magnitude, rates and nature of the land cover changes that had occurred between these dates, and; (iii) establish the spatial and temporal distribution of these changes. Land cover types were discriminated through partitioning, hybrid classification and spatial reclassification of multi-temporal Landsat imagery. The land cover products were then validated and overlaid in post-classification comparison to detect the changes between 1973 and 2011. The accuracies of the land cover maps for 1973, 1985, 2000 and 2011 were 88%, 95%, 80% and 89% respectively. Six land cover classes, namely forests-shrublands, grasslands, croplands, built-up lands, bare lands and water bodies, were mapped. Forests-shrublands dominated in 1973, 1985 and 2000 covering about 1067 km², 893 km² and 797 km² respectively, but were surpassed by croplands (953 km²) in 2011. Bare lands occupied the least area that varied between 2 km² and 7 km² during this period. Overall, forests-shrublands and grasslands decreased by 428 km² and 258 km² at the annual average rates of 1% each, whereas croplands and built-up lands expanded by 660 km² and 24 km² at the annual rates of 6% and 16% respectively. The key hotspots of these changes were distributed in all directions of the study area, but at different times. Therefore, policies that integrate restoration and conservation of natural ecosystems with enhancement of agricultural productivity are strongly recommended. This will ensure environmental sustainability and socio-economic well-being in the area. Future research needs to assess the impacts of the land cover changes on ecosystem services and to project the future patterns of land cover changes.     

Occurrence of soil erosion after repeated experimental fires in a Mediterranean environment

In the Mediterranean area, forest fires have become a first-order environmental problem. Increased fire frequency progressively reduces ecosystem recovery periods. The fire season, usually followed by torrential rains in autumn, intensifies erosion processes and increases desertification risk. In this work, the effect of repeated experimental fires on soil response to water erosion is studied in the Permanent Field Station of La Concordia, Valencia, Spain. In nine 80 m² plots (20 m long × 4 m wide), all runoff and sediment produced were measured after each rainfall event. In 1995, two fire treatments with the addition of different biomass amounts were applied. Three plots were burned with high fire intensity, three with moderate intensity, and three were unburned to be used as control. In 2003, the plots with the fire treatments were burned again with low fire intensities. During the 8-year interval between fires, plots remained undisturbed, allowing regeneration of the vegetation–soil system. Results obtained during the first 5 months after both fire experiments show the high vulnerability of the soil to erosion after a repeated fire. For the burned plots, runoff rates increased three times more than those of 1995, and soil losses increased almost twice. The highest sediment yield (514 g m^− 2) was measured in 2003, in the plots of the moderate fire intensity treatment, which yielded only 231 g m^− 2 of sediment during the corresponding period in 1995. Runoff yield from the control plots did not show significant temporal changes, while soil losses decreased from 5 g m^− 2 in the first post-fire period to 0.7 g m^− 2 in the second one.     

Environmental changes,remote sensing,and infrastructure development: The case of Egypt's East Port Said harbour

Using Landsat TM data, this article examines the environmental impact of the East Port Said harbour project on the surrounding landscape. The optimum three-band combination and the most appropriate multispectral bands were selected to enhance the images and monitor land cover changes for the periods of 1984–1991 and 1991–2003. The results indicate that wetland areas declined from 103 km² in 1984 to 30 km² in 2003. In addition, the surface area of El-Malha Lake has shrunk from 27 km² to 18 km² over the same period. In contrast, the area covered by salt crust has increased from 11 km² in 1984 to 19 km² in 2003. Urban land use and designed cultivated lands were also significant in 2003, covering 49 km² and 71 km², respectively. The rate of shoreline change between 1984 and 2003, the period when the East Port Said harbour was constructed, was calculated. Vector data indicate that the rate of shoreline loss was ?13 m/year from 1984 to 1991 and ?15 m/year from 1991 to 2003. Despite the fact that construction of the East Port Said harbour caused significant changes in the study area, there are several factors controlling coastline and land cover changes including industrial development and fish cultivation farms.     

Landscape transformations in savannas of northern South America: Land use/cover changes since 1987 in the Llanos Orientales of Colombia

This study presents a detailed spatial, quantitative assessment of the land use/cover changes (LUCC) in the savanna region of Llanos Orientales in Colombia. LUCC was determined from multitemporal satellite imagery (Landsat and CBERS) from 1987 to 2007. Systematic landscape transitions were identified and put in the context of population change and economic activity. The results showed that during the period 1987 to 2007, 14% of the study area underwent some kind of land use/cover change, with most change occurring in the last decade. Systematic transitions were observed from flooded savannas to crops and exotic pastures. An important land cover change was linked to the expansion of palm oil plantations from 31 km² in 1987 to 162 km² in 2007. The observed changes are shown to be related to the economic and market-oriented-development from before 1970 to the present day. Based on the future economic development plans, the Llanos Orientales will continue to undergo significant change as an estimated 70% of the 17,000 km² have been identified for conversion to plantation, or for petroleum and mining purposes. We provide recommendations for future economy integrated conservation, by proposing the implementation of a Llanos ecological network.     

Wildfire-Migration Dynamics: Lessons from Colorado's Fourmile Canyon Fire

The number of people living in wildfire-prone wildland–urban interface (WUI) communities is on the rise. However, no prior study has investigated wildfire-induced residential relocation from WUI areas after a major fire event. To provide insight into the association between sociodemographic and sociopsychological characteristics and wildfire-related intention to move, we use data from a survey of WUI residents in Boulder and Larimer counties, Colorado. The data were collected 2 months after the devastating Fourmile Canyon fire destroyed 169 homes and burned more than 6,000 acres of public and private land. Although this study is working with a small migrant sample, logistic regression models demonstrate that survey respondents intending to move in relation to wildfire incidence do not differ sociodemographically from their nonmigrant counterparts. They do, however, show significantly higher levels of risk perception. Investigating destination choices shows a preference for short-distance moves.     

Land Changes Fostering Atlantic Forest Transition in Brazil: Evidence from the Paraíba Valley

The Atlantic Forest biome has only 13 percent of its pristine vegetation cover left. This article analyzes the consequences of land changes on forest cover in the Paraíba Valley, São Paulo state, Brazil, from 1985 to 2011. Multitemporal satellite image classifications were carried out to map eight land use and land cover classes. The forest cover increased from 2,696 km² in 1985 to 4,704 km² in 2011, mostly over areas of degraded pastures. The highest rates of afforestation were observed within protected areas around eucalyptus plantations. On the other hand, deforestation processes were concentrated on areas covered by secondary forests. Socioeconomic changes taking place in particular Brazilian settings, such as industrialization and agricultural modernization, allied to the Paraíba Valley's natural biophysical constraints for agricultural production, have led the region to experience a remarkable case of forest transition.     

Impacts of land use and fire on the loss and degradation of lowland forest in 1983–2000 in East Kutai District, East Kalimantan, Indonesia

Deforestation and forest degradation are proceeding rapidly in the lowland forests of Indonesian Borneo. Time series analysis of satellite imagery provides an ideal means of quantifying landscape change and identifying the pathways which lead to the changes. This study investigates the forest and land cover changes by classifying Landsat MSS (Multispectral Scanner), TM (Thematic Mapper) and ETM+ (Enhanced Thematic Mapper Plus) images over three time periods (1983–90, 1990–98, and 1998–2000), creating land cover maps for each year and change trajectories for each year-pair. The study area chosen covers an area of 2160 km² of undulating topography and alluvial plains in the East Kutai District of East Kalimantan Province, which in the 1980s was covered mostly with lowland dipterocarp forest; today the landscape is a patchwork dominated by oil palm and timber plantations and degraded forest. We relate land cover change data to land use allocation and to fire impacts based on fire hotspot distribution and fire damage information. The multidate land cover change trajectories provide an insight into the forest loss and degradation pathways over the 17-year period spanning the first entry of commercial logging concessionaires, followed by a government-sponsored transmigration scheme, government-licensed timber and oil palm plantations and, finally, the devastating fires of 1998. The results show a mean deforestation rate of 42 km² or 6 per cent per year for 1983–2000, rising to 10 per cent per year for 1990–98; by 2000, 70 per cent of forest initially damaged by fire and drought during the 1982–83 El Niño event was classified as non-forest. Although our study area is perhaps a worst-case scenario in terms of land use planning outcomes, the lessons from this research are directly applicable to scenario prediction for informed forest and land use planning and monitoring.     

Analysing urban sprawl and land consumption patterns in major capital cities in the Himalayan region using geoinformatics

In the present study, spatio-temporal urban sprawl and land consumption patterns were analysed in seven capital cities located in the Himalayan region during 1972, 1991 and 2015 using multi-temporal satellite images. The study exhibits that capital Himalayan cities experienced rapid growth (830.92%) with high population increase (333.45%) during the observation period (1972–2015). The significant urban growth was observed in the cities of western and middle Himalayan region viz., Srinagar (9.36 km²–142.19 km²), Kathmandu (11.38 km²–92.58 km²) and Dehradun (4.1 km²–50.09 km²) in the higher altitudes due to remarkable increase in the population (0.5–1 million persons) during 1972–2015. On the contrary, Itanagar (7.19 km²), Gangtok (7.09 km²), Shimla (3.04 km²) and Thimphu (2.93 km²) observed less urban growth with moderate to low population growth (i.e., 0.05 to 0.15 million persons). The Shannon entropy based study exhibits that the cities viz., Kathmandu, Gangtok and Itanagar observed comparatively more dispersed urban growth during later period (1991–2015) as compared to the previous period (1972–1991) whereas, the remaining cities observed comparatively less dispersed urban growth during later period. The temporal land consumption pattern exhibits low density urban growth in Srinagar, Dehradun and Kathmandu, as observed with decrease in population density and increasing land consumption during 1972–2015 as compared to other cities, wherein urban densification was evident with increase in population density and decrease in land consumption. The cities in central and western Himalayan region observed high urban growth as compared to cities in eastern Himalayan region. The result shows that the capital cities contributes insignificant proportion (0.5%; 314 km²) of urban area in Himalayan region and accommodating large (ca. 4 million) population during 2015. The study indicates unplanned and haphazard growth in all capital Himalayan cities, leading towards urban densification as well as dispersion in the periphery with varied pattern and intensity. The specific trends and patterns of urban and population growth are governed by geographical as well as socio-economic-political factors at local to regional scale. The high population pressure induced higher risk to the urban residents as well as constrained urban growth over higher vulnerable zones. The study necessitates implementation of suitable urban planning methods considering socio-economic and physico-cultural characteristics of the region.     

Influences of forest roads on the spatial patterns of human- and lightning-caused wildfire ignitions

Understanding the spatial patterns of fire ignitions and fire sizes is essential for understanding fire regimes. Although previous studies have documented associations of human-caused fire ignitions with road corridors, less consideration has been given to understanding the multiple influences of roads on the fire regime at a broader landscape-scale. Therefore, we examined the difference between lightning- and human-caused fire ignitions in relation to forest road corridors and other anthropogenic and biophysical factors in the eastern Cascade Mountains of Washington State. We used geographical information systems and case-control logistic regression models to assess the relative importance of these explanatory variables that influence the locations of lightning versus human-caused ignitions.We found that human-caused ignitions were concentrated close to roads, in high road density areas, and near the wildland-urban interface (WUI). In contrast, lightning-caused ignitions were concentrated in low road density areas, away from WUI, and in low population density areas. Lightning-caused ignitions were also associated with fuels and climatic and topographic factors. A weak but significant relationship between lightning-caused fire and proximity to gravel roads may be related to fuels near roads or to bias in detection and reporting of lightning-caused fires near roads. Although most small fires occurred in roaded areas, they accounted for only a small proportion of the total burned area. In contrast, the large fires in roadless and wilderness areas accounted for most of the burned area. Thus, from the standpoint of the total area burned, the effect of forest roads on restricting fire size is likely greater than the impact of roads on increasing fire ignitions. The results of our study suggest that roads and their edge effect area should be more widely acknowledged as a unique type of landscape effect in fire research and management.     

Human-ignited wildfire patterns and responses to policy shifts

Development of efficient forest wildfire policies requires an understanding of the underlying reasons behind forest fire occurrences. Globally, there is a close relationship between forest wildfires and human activities; most wildfires are human events due to negligence (e.g., agricultural burning escapes) and deliberate actions (e.g., vandalism, pyromania, revenge, land use change attempts). We model the risk of wildfire as a function of the spatial pattern of urban development and the abandonment/intensity of agricultural and forestry activities, while controlling for biophysical and climatic factors. We use a count data approach to model deliberately set fires in Galicia, N.W. Spain, where wildfire is a significant threat to forest ecosystems, with nearly 100,000 wildfires recorded during a thirteen-year period (1999–2011). The spatial units of analysis are more than 3600 parishes. Data for the human influences are derived from fine-resolution maps of wildland–urban interface (WUI), housing spatial arrangements, road density, forest ownership, and vegetation type. We found wildfire risk to be higher where there are human populations and development/urbanisation pressure, as well as in unattended forest areas due to both rural exodus and a fragmented forest ownership structure that complicates the profitability of forestry practices. To better help direct management efforts, parameter estimates from our model were used to predict wildfire counts under alternative scenarios that account for variation across space on future land-use conditions. Policies that incentivize cooperative forest management and that constrain urban development in wildlands at hotspot fire locations are shown to reduce wildfire risk. Our results highlight the need for spatially targeted fire management strategies.     

A field study of wind erosion following a grass fire on the Llano Estacado of North America

Interactions between earth, wind, and fire have always played an important role in the formation and evolution of the level plains of the Llano Estacado of North America. The uppermost sediments of this vast region are aeolian deposits, formed by aeolian deposition into grassland vegetation. Grass cover enhances aeolian deposition by slowing near-surface winds and vegetation secures sediments once they are deposited. The benefits of grass cover, however, are lost when occasional fires remove protective vegetation from fields. After a fire, the underlying soil surface becomes exposed and susceptible to wind erosion until the vegetative cover is re-established. The purpose of this study was to explore the post-fire recovery process by monitoring temporal variations in aeolian transport and changes in the threshold velocity of a burned grass field located in Lubbock County, Texas. A continuous record of wind erosion activity was obtained during a six-month period as the surface recovered from a highly erodible state to a more vegetated and stable surface. Results suggest that the threshold wind speed of the field increased from less than 10 m/s immediately following the fire to above 19 m/s in a three-month period as vegetation naturally recovered.     

Fire and vegetation history during the last 3800 years in northwestern Montana

Foy Lake in northwestern Montana provides a record of annual-to-decadal-scale landscape change. Sedimentary charcoal and pollen analyses were used to document fire and vegetation changes over the last 3800 years, which were then compared to similar records from AD 1880 to 2000. The long-term record at Foy Lake suggests shifts between forest and steppe as well as changes in fire regime that are likely the result of climate change. Fire activity (inferred from the frequency of charcoal peaks) averaged 18 fire episodes/1000 years from 3800 to 2125 cal year BP, and increased from 16 fire episodes/1000 years at 2125 cal year BP to 22 episodes/1000 years at 750 cal year BP, a period when the pollen data suggest that steppe vegetation yielded to increasing patches of forest cover. Between 2125 and 750 cal year BP, increased forest cover produced more background charcoal than before and after this period, when vegetation was dominated by steppe. Between 750 and 75 cal year BP steppe has expanded and fire episode frequency averaged 33 episodes/1000 years, increasing to a maximum of 40 episodes/1000 years at ca. 300 cal year BP and then decreasing to present levels. Since AD 1880, the pollen record indicates an increase in shrubs and grasses from AD 1895 to 1960 as a result of vegetation changes associated with timber harvesting and livestock grazing. No fires have been documented in the Foy Lake watershed since AD 1880. Charcoal from the extralocal fires of AD 1910, burning over 4,111,249 ha in Idaho, Montana, and Wyoming, however, is present in Foy Lake. Between AD 1970 and 2000, increased arboreal pollen in the record is consistent with observations that the forest has become more closed. The activities of Euro–Americans have led to a decline in forest cover between AD 1880 and 1970, followed by a recent increase as trees are now growing in areas previously occupied by steppe. Euro–Americans are likely the cause of a reduction in fire activity in watershed since AD 1880.     

Post-fire plant recovery in the Mojave and Sonoran Deserts of western North America

Increasing wildfire activity is one of the most pressing management concerns in arid lands of the American West. To examine post-fire recovery of perennial vegetation in the Mojave and Sonoran Deserts, I analyzed data systematically synthesized from the literature. Post-fire sprouting by desert perennials is generally limited but varies among species. For example, only 3–37% of Larrea tridentata sprouted compared to 64–86% of Yucca schidigera. Four of five studies measuring recovery of perennial cover reported close relationships (r² = 0.67–0.99) between time since fire (TSF) and cover. In fact, three studies measuring the longest TSF (≥37 years) found that cover had returned to within 10% cover of unburned areas within approximately 40 years. Conversely, post-fire species composition exhibited little convergence with unburned composition in five of six studies even 47 years after fire. Sphaeralcea ambigua, Gutierrezia spp., Achnatherum speciosum, Encelia spp., Hymenoclea salsola, and Baileya multiradiata had the highest burned:unburned abundance ratios, although overall post-fire community composition differed between the Mojave and Sonoran Deserts. Analyzing the literature as a whole suggested some generalities (e.g., that perennial cover reestablishes faster than composition), but more work is required for improving specific knowledge about plant recovery among fires, sites, species, and climates.     

Quantitative estimation and spatial reconstruction of urban and rural construction land in Jiangsu Province, 1820–1985

Land cover is the most evident landscape signal to characterize the influence of human activities on terrestrial ecosystems. Since the industrial revolution, the expansion of construction land has profoundly changed the status of land use coverage and changes. This study is proposed to reconstruct the spatial pattern of construction land (urban construction land and rural settlement land) for five historical periods over the past 200 years in Jiangsu Province with 200 m × 200 m grids on the basis of quantitative estimation. Urban construction land is estimated based on data about city walls, four gates along walls, and other socio-economic factors. Rural settlement land is calculated based on the rural population and per capita housing allowance. The spatial pattern of historical construction land is simulated based on the distribution of modern construction land in 1985 with a quantitative-boundarysuitability control method and thorough consideration over connectivity of different land use types. The study concludes that: (1) the amount of construction land in Jiangsu Province is estimated at 963.46 km² in 1820, 1043.46 km² in 1911, 1672.40 km² in 1936, 1980.34 km² in 1952 and 10,687.20 km² in 1985; and (2) the spatial distribution of construction land features the great proclivity to water bodies and main roads and the strong polarization of existent residence. The results are verified directly and indirectly by applying the trend verification of construction land changes and patterns, the correlation analysis between rural settlement land and local arable land, and quantitative accuracy test of the reconstructed construction land to actual historical survey maps covering four sample regions in 1936.