EVALUATION OF FOREST FIRES IN PARANÁ IN 2018 AND 2019

Forest fires represent significant environmental, economic, and social damage in many countries. Historical knowledge of their characteristics aids in making preventive decisions, as well as fighting forest fires. However, the general data of fires in Paraná are outdated. The objective of this study was to evaluate the forest fires in the state of Paraná in 2018 and 2019, surveying the following information: municipality and region affected; month and day of occurrence; and vegetation type. To this end, data obtained from the Paraná Fire Department through the SysBMNew-CCB platform were analyzed. The fire density by region was verified and compared through cluster analysis. Compared to the previous year, 2019 showed a 42.25% increase in the number of fires. In both years, most forest fires occurred in the North-central region, followed by the Metropolitan Region of Curitiba. The municipality of Curitiba recorded the highest number of fires in both years. According to the Fire Department classification, the vegetation type most affected by the fires was vacant lots. From the data obtained, we verified the need for environmental education measures aimed at the prevention of fires in vacant lots. Further research is recommended so that a profile of forest fires can be traced in the state and thus base prevention and control measures.


INTRODUCTION
Forest fires represent a major concern for many ecosystems (KUCUK et al., 2018), since they can cause imbalance and damage of economic, social, and environmental nature (BOWMAN et al., 2011). According to Rodríguez et al. (2013), the frequency of fires has increased in recent years on a global level, despite the available technologies and effort of governments and international organizations to fight them.
In view of this scenario, investing in actions to prevent and fight forest fires has become increasingly necessary. According to Torres et al. (2010), knowledge of the characteristics of fires is needed to enact policies on fire control, prevention, and management. For that end, statistics on the occurrence of fires in vegetation are the main tools, since the frequency of fires is a primary indicator to determine their characteristics (CHANG et al., 2015).
Time, place of occurrence, and quantitative distribution of fires throughout the year are variables that assist prevention planning, since they allow us to identify periods with higher risk of forest fires (RODRÍGUEZ et al., 2013). Assessment of which vegetation types are most susceptible to fire is also relevant, as ground for adopting specific management actions that may reduce the occurrence and effects of fires (SAMARA et al. 2018;TIAN et al. 2013). Particularly in the case of fires in urban areas and their interfaces, these data may lead to the FLORESTA formulation of guidelines toward more appropriate decision-making and planning. For Chas-Amil et al. (2013), anthropic activities occurring at urban-rural interfaces increase the likelihood of forest fires. In these interfaces, fires can have serious consequences for property and land use, in addition to posing a serious threat to life.
The development and implementation of effective prevention and control plans can only be achieved through analysis of accurate data on the characteristics of forest fires (VOSGERAU et al., 2006). Studies on the occurrence of fires need to be carried out continuously in order to create a consistent database that allows the prediction of fire hazard seasons. However, the latest data in published studies on fires in the State of Paraná is from 2011.
Within this context, the objective of this study was to characterize the forest fires that occurred in the state of Paraná in 2018 and 2019, in terms of region, time of occurrence, and vegetation types, in order to provide updated data for the fight and prevention of fires.

Characterization of the study area
The state of Paraná, located in the southern region of Brazil, has a land area of 199,879.5032 km², which corresponds to 2.5% of Brazil (ITCG, 2019).
According to the database provided by Alvares et al. (2013) and to the Köppen classification, the predominant climates in the state are Cfa (humid subtropical) and Cfb (temperate oceanic), with the presence of Af (tropical rainforest), Am (tropical monsoon), and Aw (tropical savannah) in the northwest of the state ( Figure  1A). The highest averages of annual rainfall in the state are concentrated in the East and Southwest regions ( Figure  1B), whereas the highest averages of annual temperature are in the East and Northwest regions ( Figure 1C).   Regarding vegetation, the state consists of different phytogeographic units: to the East, from the coastal plain to part of the Ribeira Valley, it is a dense Ombrophilous Forest; to the west of the Serra do Mar it is a mixed Ombrophilous Forest; in the North and West regions, it is a Semidecidual seasonal Forest. There are also remnants of steppe, interspersed with capons and gallery forests, usually located in the higher portions of the three plateaus of Paraná, and isolated areas of Savanna (Cerrado), located in the North and Northeast regions (RODERJAN et al., 2002).

Database
For the analysis of the forest fires that occurred during 2018-2019 in Paraná, the new database of the Fire Department of the Military Police of Paraná (SysBMNew-CCB) was used. The data analyzed from the records of the institution were: -Municipality of occurrence; -Month of occurrence; -Day of the week of occurrence; -Type of vegetation affected. Only data from 2018 and 2019 were used due to the fact that, until 2017, the Fire Department adopted the category of "environmental fires" in its records, which covered both waste fires and forest fires. With the implementation of SysBMNew in 2017, the nature of the fire was added, in a division of "vegetation" and "others", which provides higher reliability in analyses of forest fire data.
A screening of the fire records was carried out in order to eliminate data that could represent dubious interpretations, such as the registration of the vegetation type as "garbage".
The  An adaptation of the fire density (FD) index was used for the comparison between geographical regions: the number of records was divided per thousand hectares of total area of each geographical region, instead of per thousand hectares of vegetation cover of each geographical region. This adaptation was carried out because there are failures in the estimates of vegetated areas in urban centers, which result in an underestimation of park areas and vacant lots. The geographical regions were grouped with respect to FD by applying a cluster analysis following the Ward Method and the Euclidean squared distance.
The software used to run the maps was Arcgis Desktop (version 10.5). Excel (version 2016) and Statgraphics Centurion XVI (version 16.1.03) were used for the data analysis.

RESULTS
The amount of forest fires recorded in 2018 and 2019 in Paraná is shown in Figure 3. In 2018, 7,611 fires were recorded, distributed among 209 municipalities of 11 geographic regions. The North-central region presented the highest number of occurrences, with 1,962 forest fires (25.78%). Regarding municipalities, Curitiba had the highest number of occurrences, 476 (6.25%), followed by Maringá with 292 (3.84%), and Ponta Grossa with 240 (3.15%).
In 2019, there were 10,827 forest fires in 258 municipalities, a 42.25% increase in the number of fires over the previous year. The North-central region had once again the highest number of fires, 2,438 occurrences (22.52%). Curitiba also had once more the highest number of fires among cities, 501 (4.63%), followed by Cascavel with 427 (3.94%), and Ponta Grossa with 301 (2.78%). Comparing the two years, the Southwest had the largest increase in the number of fires among regions, with a 143.7% increase in 2019, followed by the West, which showed an 80.4% increase. Figure 4 shows the density of fires by region in the years analyzed and the cluster analysis among the geographic regions. Regions were grouped according to similarity, using fire density data. North-central showed the highest FD of all regions, with 0.8 (2018) and 1.0 (2019) fires for every thousand hectares of area, followed by the Metropolitan region of Curitiba, which had a FD of 0.7 and 1.0, respectively.  In 2019, August showed the highest number of fires in most regions. Both in 2018 and 2019, the months with the highest number of fires (July and August) corresponded to winter, a season with historically lower rainfall levels and lower relative humidity in the state. Relative fire frequencies by day of the week are shown in Table 3. The results varied among regions, but there was a slight concentration in the number of fires on Friday and Saturday.  Table 4 shows affected vegetation types by region in 2018 and 2019.

DISCUSSION
When analyzing forest fires in Paraná from 1991 to 2011, Vosgerau et al. (2006) found that a region comprising part of the North-central and the North-pioneer was the most affected by fires in that period, with 25.85% of the total of fire records. As for the municipalities, they found that Londrina had the highest number of fires with 3,552 occurrences (22.35%), followed by Ponta Grossa with 2,339 (14.72%), and Curitiba with 2,201 records (13.85%).
In another study on forest fires in Paraná between 2005 and 2010, Tetto et al. (2012) observed that the Northwest region was more susceptible to fires, due to environmental factors such as climatic characteristics, vegetation cover, and the use of fire in agricultural practices. In the same study, they also verified that the coastal region was the least susceptible to fires, due to the region's higher average rainfall levels and specific vegetation type, which tends to inhibit fire initiation and spread. These findings corroborate the data found in our study.
Regarding months with a higher concentration of fires, our results are in line with what has been verified by other studies carried out in the state. Vosgerau et al. (2006) defined June to August as the fire hazard season since these months showed 53.18% of the fires in the analyzed period, especially August, with 24.47% of the records.
In the same sense, Tetto et al. (2012) also used the records of the Paraná Military Police's Fire Department and found that June to September was the fire hazard season, since this interval had 52.5% of the fires in the period they examined. In a study on forest fires in the municipality of Ponta Grossa-PR, Kovalsyki et al. (2014)  No day of the week had a significantly higher concentration of fires in our study, which corroborates the findings of Vosgerau et al. (2006) and Tetto et al. (2012).
The fact that most of the fires in this study occurred on vacant lots shows the importance of investing: in environmental education, so that the population learns not to handle these places with fire; in actions for a better use of these spaces; and also in inspection, in order to prevent fires and the damage they cause.
According to Ferreira et al. (2018), vegetation fires in urban areas and their interfaces are an environmental, social, and economic problem since they damage flora and fauna, directly or indirectly affect the population, and damage properties and other human resources. In addition, fires in urban areas may damage the local microclimate, affect air quality and the landscape, and also pose risks to the visibility of drivers. Torres et al. (2010), in a study on vegetation fires in the urban area of Juiz de Fora-MG, found that 43.94% of occurrences happened in vacant lots throughout the city from 1995 to 2004. The authors state that the amount of fires at these sites confirms their anthropic influence, since fire is used to clear these areas.
We recommend the continuation of this study for at least 3 more years, so that a profile of forest fires in Paraná can be traced with greater precision, and, thus, adequate prevention and control measures can be developed.

CONCLUSION
Based on our results, we concluded that: • Vacant lots are the places most affected by forest fires in Paraná. The large number of fires in vacant lots is related to the common practice of clearing land with fire. • To reduce the amount of fires in vacant lots, we recommend environmental education programs for the population and the adoption of effective prevention and inspection measures. • In 2018 and 2019, the North-central region had the highest number of forest fires.
• In both years, the municipality with the highest number of fires was Curitiba.
• There was a 42.25% increase in the number of fires from 2018 to 2019. Southwest and West regions had the highest percentage increases. • The data obtained in this study follow the trend of other studies carried out in the state.