CHARACTERIZATION OF THE TINGUI MUNICIPAL PARK MICROCLIMATE, CURITIBA, PARANÁ STATE, BRAZIL, AND THE OCCURRENCE OF CAPYBARAS (HYDROCHOERUS
HYDROCHAERIS, LINNAEUS, 1766)
Ariádina Reis Almeida1; Luciana Leal2; Daniela Biondi3; Angeline Martini4;
Everaldo Marques de Lima Neto56
ABSTRACT
Green areas in urban environments are essential, because in addition to approaching men to nature, they are important vegetation remnants that promote balance and microclimatic support for the fauna conservation of a region. On the Tingui Municipal Park in Curitiba City, Paraná State, Brazil, the occurrence of capybaras (Hydrochoerus hydrochaeris, Linnaeus) is common in areas largely used by park goers. This study analyzed the differences of microclimate environments where capybaras dwell and their relationship with the behavior of these animals. The park was characterized in different environments based on the predominance of landscape elements, such as islands of grass and sparse trees, where we collected data on temperature and relative humidity. The results indicated that the composition and provision of vegetation, as well as proximity to water in the studied area, influenced the variations in temperature and humidity.
Key-words: Green areas; Urban microclimate; Capybara; Thermoregulation
CARACTERIZAÇÃO MICROCLIMÁTICA DO PARQUE MUNICIPAL TINGUI, CURITIBA – PR E A OCORRÊNCIA DE CAPIVARAS (HYDROCHOERUS HYDROCHAERIS, LINNAEUS, 1766)
RESUMO
As áreas verdes são fundamentais em ambientes urbanos, porque além de garantir a proximidade do homem com a natureza, são importantes remanescentes vegetacionais que promovem o equilíbrio microclimático e dão suporte para a conservação da fauna de uma região. No Parque Municipal Tingui na cidade de Curitiba - PR é comum encontrar capivaras (Hydrochoerus hydrochaeris, Linnaeus) em áreas de uso intenso pela população visitante. Esta pesquisa teve como objetivo analisar as diferenças microclimáticas dos ambientes onde as capivaras ocorrem e sua relação com o comportamento destes animais. Neste sentido, a área do parque foi caracterizada em diferentes ambientes através da predominância de elementos da paisagem, tais como: ambientes de ilhas, de gramado e com árvores esparsas. Em cada um destes ambientes foram coletados dados de temperatura e umidade relativa do ar. Os resultados indicaram que a composição, a disposição da vegetação e a proximidade da água nos ambientes estudados, influenciaram as variações de temperatura e umidade.
Palavras-chave: Áreas verdes; Microclima urbano; Capivara; Termorregulação.
1 Mestranda do Programa de Engenharia Florestal da UFPR. ariadina_almeida@yahoo.com.br 2
Doutoranda do Programa de Pós-graduação em Engenharia Florestal/UFPR. luciana_paisagem@yahoo.com.br
3 Drª. Professora Associada III, Depto. Ciências Florestais, UFPR, Bolsista Produtividade em Pesquisa – CNPq, dbiondi@ufpr.br 4 Mestranda do Programa de Engenharia Florestal da UFPR. martini.angeline@gmail.com
5 Doutorando do Programa de Pós-graduação em Engenharia Florestal/UFPR. everaldo.limaneto@gmail.com 6
recebido em 28.05.2012 e aceito para publicação em 15.06.2013
INTRODUCTION
Urban parks, in addition to providing benefits of conservation to the area they are inserted, the play an important role in the conservation of hydric resources, scenic beauty, soil protection by preventing and controlling erosion and siltation of water bodies, ensuring river flows, protection of historical and cultural buildings, maintenance and production of wild fauna, recreational areas in contact with nature; knowledge acquisition by environmental education, besides providing air and water quality and influence the regional economic growth (PEIXOTO et al., 2005).
Urban parks are green areas that play a significant role to regulate urban climate (MARTINEZ-ARROYO; JAUREGUI, 2000; YU; HIEN, 2006). The vegetation cover and water bodies in the green areas help control temperature and relative humidity in the air (TYRVÄINEN et al., 2005). Besides the climatic benefits, from the ecological perspective, the green areas are essential, once they allow to safeguard the biological identity of the regions by preserving the fauna and flora of each municipality (DANTAS; SOUZA, 2004). Parks, as
well as squares and gardens, act as biologic fragments interconnected by street afforestation, comprising an urban complex that is essential for the wild life (RODRIGUES et al., 2002).
The green areas in the city of Curitiba, Paraná State, Brazil, house several species from the Brazilian fauna, including the largest rodent in the Americas known as the capybara (Hydrochoerus hydrocheris Linaeus, 1766). The capybara is an herbivore that feeds on low vegetation (grass), shrubby and aquatic vegetation. It is a semi-aquatic animal and uses water bodies as a vital resource for its survival (FERRAZ et al., 2010).
For Arzua et al. (2008), the Tingui Municipal Park is home for most capybaras in the municipality of Curitiba. Therefore, it has become a site of great scientific interest to carry out research on microclimate and fauna in an urban environment. In this sense, this study analyzed the differences of temperature and air relative humidity in the areas mostly used by the capybaras in the Tingui Park and related the data to the behavior of groups of animals that dwell in these areas.
MATERIAL AND METHODS
Study site
The study was carried out in the Tingui Municipal Park, in the city of Curitiba, Paraná State, Brazil (25°23’43”S and 49°18’15”W) (Figure 1). The park
covers an area of 380 mil m2 and all of its extension is boarded by the Barigui River, the main river of the Rio Barigui basin.
Ariádina Reis Almeida et al.
Figure 1. Location Curitiba City and the study site .
The park was created in 1994 in an area of Alluvial Rain Forest with evidences of sand extraction. Alluvial soils and embankments with a slope of up to 5%, which are areas susceptible to floods due the soil saturation, compose most part of the park. The higher parts with a slope greater than 10% are located in the central-southern portion of the park, covering a continuous forest strip (PLANO DE MANEJO, 2009).
The climate in the region is Cfb (Köppen classification) with humid temperate (subtropical) climate, mesothermal, without dry seasons, but with mild summers and winters with constant frosts and occasional snowfall. East winds are predominant and the annual wind speed is 2.1 m/s. The average temperatures are 20.94ºC in the summer and 13.77ºC in the winter. The average annual precipitation is 1,563.30 mm and the average RH in the air is 80.81% (IPPUC, 2011).
Methods
The study was carried out in the central-northern region of the park, where capybaras dwell (Figure 2). This region is represented by a large extension
grass, some fragments of trees and two islands (Figures 2 and 3), with tree cover surrounded by a large lake.
Parque Tingui
Figure 2. The Tingui Municipal Park with the areas inhabited by capybaras.
Legend: (L) lake, (VA/a) woody/shrubby vegetation, (G) grass (Rio) river (AV) visiting area, (Rua) street.
ILHA - 1 ILHA - 2 ILHA - 3 ILHA - 4 ILHA - 5
PARQUE TINGUI
USO DO SOLO
Variáveis dentro do limite do Parque Tingui ! ( capivaras L VA/a G Rio AV Rua
Ü
0 50 100mSistema de Coordenadas Geográficas UTM - WGS 84 ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (!(!(!( ! ( ! ( ! ( ! (!(!(!(!(!( ! (!(!( ! ( ! ( ! ( ! (!(!(!( ! ( ! ( ! ( ! ( ! (!(!(!(!(!(!( ! ( ! ( ! (!( ! (!( ! ( ! (!(!( ! (!( ! ( ! ( ! ( !(!(!(!(!( ! (!(!(!(!(!( ! (!( ! ( ! (!( ! (!( ! ( ! (!(!(!(!(!(!( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (!(!( ! ( ! ( ! ( 670200 670500 670800 671100 671400 7 189 200 7 1 8 960 0 7 1 900 00 7 190 400 7 1 9 080 0 7 1 9 120 0
TINGUI PARK
SOIL USE
ISLAND 1 ISLAND 2 ISLAND 3 ISLAND 4 ISLAND 5Ariádina Reis Almeida et al.
We defined five checkpoints for each collection of meteorological data for the analysis of microclimatic differences (Figure 3):
a) Island 2 – center: area surrounded by water and soil covered with litterfall, woody cover and some shrubs;
b) Island 3 – center: similar characteristics to Island 2; however, trees are more sparse and there no shrubs;
c) Island 3 – border: adjacent margin to the lake with soil covered with litterfall;
d) Sparse trees: woodland formed by sparse trees in grassland;
e) Grassland: continuous area of low vegetation (grass) without trees.
Figure 3. Characterization of the sites inhabited by capybaras in the Tingui Municipal Park, Curitiba, Paraná Stare, Brazil.
Island 2 Island 3 – Center Island 3 – Border
Sparse trees Grassland
We collected the meteorological data on March 18, 2010, between 12:00 and 04:00 pm. The variable of air temperature (°C) and air relative humidity (%) were collected in a Hobo® Data Logger RH & Temp., brand Onset, which is used to measure temperatures between – 20 and 70ºC and RH between 25-95%, previously calibrated and
programmed to store data continuously every 15 minutes.
The Hobo® sensors were installed in small wooden boxes (15x15x15 cm) and 2mm thick with lateral holes and wrapped in aluminum foil for prevent interference of solar radiation and ensure accurate data on temperature and RH (Figure 4), as proposed by Pertschi (2005).
Figure 4. Small box for data collection in the Tingui Municipal Park and sensor Hobo ® Data Logger Temp & RH
Due to the difficult access to the islands, the devices were installed with the help of employees of the Department for Parks and Squares of Curitiba City Hall, which provided boats and personnel for the installations.
Based on the data collected, we calculated the average temperature and RH in the monitoring
period. The experiments were considered as a completely randomized block design and the means were statistically tested in the F test and compared in the SNK test at 5% significance.
During the data collection, we monitored the behavior of the capybara group in the sampled sites.
RESULTS AND DISCUSSION
In the five points studied, we observed statistical differences for temperature and RH (Table 1).
Table 1. Average data on temperature and RH of the studied sites in the Tingui Municipal Park, Curitiba City, Paraná State, Brazil.
METEOROLOGICAL VARIABLES STUDIED SITES Iisland 2 Center Island 3 Center Island 3 Border Sparse Trees Grasslands Temperature (ºC) 23.6 a 26.1 b 23.3 a 23.9 a 26.4 b Relative Humidity (%) 67 c 58 ab 73 d 63 bc 56 a
Note: Means followed by the same letter in the row do not differ at 5% significance.
There was significant statistical difference between the centers of islands 2 and 3, possibly due to the
distinct composition of vegetation cover in both sites. In island 3 center, the trees are sparser and
Ariádina Reis Almeida et al.
allow solar radiation to reach the soil and, therefore, the temperature rises and RH decreases. Conversely, in island 2 center, the vegetation cover is denser and the tree crowns do not allow solar radiation to reach the soil, resulting in lower temperatures and higher RH.
We did not expect significant differences between the border and center in island 3; however, the data show otherwise. The proximity to water may have influenced the variables studied increasing RH and reducing the temperature. For Ayoade (2003), the distance to water bodies is one of the factors that influence temperature distribution; therefore, land surfaces heat up or cool down more than hydric surfaces. Kapos (1989) reports that near the borders of the forest fragments, solar radiation incidence is one of the main causes of microclimatic changes, accounting for changes in the evaporation rate and local temperature changes.
We did not observe significant statistical differences for island 2 center, island 3 border and sparse trees. This may be related to the similar vegetation cover of the islands and the site of sparse trees. For Yu and Hien (2006), temperatures measured within parks have a strong correlation with the density of vegetation cover in the area. Another peculiarity of the studied area was the similarity of temperature and RH values between island 3 center and grassland. As expected, the grassland site showed higher temperatures and lower RH, because the site allows great incidence of solar radiation, which is also explained by the vegetation composition of the site.
In general, the composition, displacement and proximity to water bodies in the studied sites directly affected the variations of temperature and RH. The afforested sites showed lower temperatures and higher RH than the non-afforested ones. These results corroborate Lorente (1966) and
Ayoade (2003), who report that the capacity to preserve RH reduces with the temperature increase and RH is directly related to water availability and evaporation rate and plant transpiration.
Although there was a significant difference between islands 2 and 3, both are equally used by the capybaras. The islands seem like a refuge for the animals. Some authors cite that in natural environments, capybaras rest and shelter themselves against predators in the non-flooding areas with woody-shrubby vegetation cover (HERRERA; MACDONALD, 1989; KRAUER, 2009; TIM, 2009).
The difference between the border and the center of the island can be a favorable factor for animals, because they are able to observe the microclimatic changes without having to leave the island and expose themselves to stressful situations of being hunted or chased. For Wells (2005) and Campeletto (2009), continuous stress may result in metabolic changes that affect the species survival.
Based on temperature values, the statistical tests defined only two types of environments (a and b), with average temperatures between 23.3 and 23.6 ºC and another environment with average temperatures between 26.1 and 26.4 ºC (Table 1 and Figure 5). For the RH variable, the test defined four environments (a, b, c and d) (Table and Figure 7). This shows that the environments analyzed show more differences for RH than for temperature values.
The animals used the environments that showed lower temperatures (Island 2 center, Island 3 border, sparse trees) during the hottest hours of the day, between 3:00 and 4:00 pm (Figures 5 to 9). In this condition, we observed some capybaras in the lakes and in shaded areas; however, some animals that remained on the grassland (hotter areas)
freshened themselves up in the muddy pools (Figure 9).
Figure 5. Behavior of the average air temperature in the five environments analyzed in the Tingui Municipal Park, Curitiba, Paraná State, Brazil.
Figure 6. Deviations for the average temperature in the five environments analyzed in the Tingui Municipal Park, Curitiba, Paraná State, Brazil.
Figure 7. Behavior of the average RH in the five environments analyzed in the Tingui Municipal Park, Curitiba, Paraná State, Brazil.
20 22 24 26 28 30 12 h00 12 h30 13 h00 13 h30 14 h00 14 h30 15 h00 15 h30 16 h00 Horários analisados T ( °C ) Ilha 1 - Centro Ilha 2 - Centro Ilha 2 - Borda Árvores esparsas Gramado 40 50 60 70 80 12h 00 12h 30 13h 00 13h 30 14h 00 14h 30 15h 00 15h 30 16h 00 Horários analisados UR (% ) Ilha 1 - Centro Ilha 2 - Centro Ilha 2 - Borda Árvores esparsas Gramado Island 1 – center Island 2 – center Island 2 – border Sparse trees Grassland Time analyzed
Island 1 Island 2-b Sparse trees Grassland Island 2-c
Island 1 – center Island 2 – center Island 2 – border Sparse trees Grassland Time analyzed
Ariádina Reis Almeida et al.
Figure 8. Deviations for RH in the five environments analyzed in the Tingui Municipal Park, Curitiba, Paraná State, Brazil.
Figure 9. Muddy pool used by capybaras in the Tingui Municipal Park Tingui, Curitiba, Paraná State, Brazil
“Island 3 center” showed the greatest variation of temperature and RH in the period observed. During the study period, we observed two large capybara groups, and each group occupied one of
the islands. In island 2, the group was composed of adult animals, while in island 3, the group was formed by adults, young animals and offspring, indicating that this group is reproducing. For Alho
RH (%) Island 1 Island 2-b Sparse trees Island 2-c Grassland
(1986), in the wild, females shelter themselves in a dry and dense forest until their progenies are able to dislocate with adults to other places in search of food. Therefore, island 3 seems the ideal environment for groups in reproduction, given that progenies can enjoy the microclimatic changes without suffering stress of being hunted or chased, while adults have the grassland and forest border as food source.
Capybaras gather in cooler environments during the hot moments of the day.
Endothermic mammals show average body temperature of 37°C (EL-KOUBA, 2005); however, this temperature varies along the time due to the several circumstances, such as room temperature, metabolic activity, health conditions, among others. To control the thermal variations that are harmful to the good functioning of the body, mammals have sweat glands. In capybaras, these glands are little developed and sparsely distributed, therefore, little efficient in thermal cooling. To solve the problem, capybaras, similarly to pigs, developed a behavior for thermal regulation to increase heat loss through the body surface and therefore maintain the thermal balance (PEREIRA et al., 1980). These animals use the water in lakes or rivers or mud to keep the body thermal balance (PEREIRA et al., 1980). For Ferraz et al. (2010), this is an biophysical adaptation to the environment. In general, capybaras gather near water bodies and move away only to feed. They usually rest the entire morning, and in the afternoon, they use the water or mud to cool themselves and feed (grass), mainly, at the end of the afternoon or early in the morning, spending the night grazing. This behavior is affected by seasonality, climatic factors and frequency of visits to the park (HERRERA;
MACDONALD, 1987 and 1989; SANTOS et al., 2005).
Maintaining the body temperature within ideal limits for the good biological functions is essential for endothermic animals (HARDY, 1981). For Veríssimo (2008), the stress caused by the heat causes several effects on the metabolism of the animal, causing changes to the behavior, such as reduction of food intake, besides reproduction problems and cortisol release leaving the body vulnerable to diseases. For Quesada et al. (2001), each animal species has characteristics that determine its behavior of grazing in the shadow, sun, rest and feeding time, showing its capacity to adapt to the environment.
For some authors (ALHO et al., 1987; HERRERA; MACDONALD, 1987; 1989), water is a vital resource for capybaras, and the main factor that influences the formation and maintenance of social groups of the species. These animals have a strong association to water bodies and depend on them for their reproduction, escape and thermal regulation. We observe the importance to have an environment with essential characteristics to maintain capybaras in semi-natural environments, as in the case of the parks in Curitiba City. The environments in the Tingui Municipal Park and their distribution with the formation of islands and shaded environments seem to favor the maintenance of these animals in an urban environment. This ensures the preservation of local fauna allowing the local population to enjoy and learn about the behavior of the species in an urban context. Therefore, it is possible to provide contact with nature along the time, according to Vigotsky (1994), a condition forgotten by modern populations.
Ariádina Reis Almeida et al. CONCLUSION
In the most frequented places by the capybaras in the Tingui Municipal Park, we observed differences in temperature and relative humidity. The results show that environments with water bodies, muddy
pools and vegetation cover associated to shading seem to work as body thermal regulators for the capybaras in the park.
ACKNOWLEDGMENTS
To the Department of Parks and Squares of the Municipal Secretary in Curitiba City for the help in collecting the data.
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