## 2 Data and Methods  
### Research Site  
The study was conducted in two adjacent forest complexes in Poland: Puszcza Solska (the Solska Forest) and Roztocze National Park (Figure 1). The Solska Forest is a large forest complex in the southern part of Lublin Voivodeship and in the north-eastern part of Subcarpathian Voivodship, Poland. It lies in the Sandomierska Basin, on the Bilgorajska Plain, south of the Roztocze Mountain Range. The Solska Forest is a natural continuation of the Sandomierska Forest to the west. Southeasternwards, the Solska Forest reaches the Polish-Ukrainian frontier, and in the vicinity of the city of Narol it merges with the Roztocze Forests. The Roztocze National Park is a northern continuation of the Solska Forest. It comprises the Upper Wieprz River valley and adjacent parts of Lubelska Upland and Sandomierska Basin. The climate of the study area has been described on the basis of [PERSON] and [PERSON] [21]. The average daily insolation in the province of Lublin amounts to 4.4 h, _i.e._, 1600 h a year. During the year maximum insolation values are recorded in July and August and amount to 7-8 h on the average, whereas the lowest value of 1 h only is noted in December. The degree of cloudiness over the area of the Lublin province is fairly diverse. Mean yearly degree of cloudiness in the area of Zamosc ranges between 6.3 and 6.4 (in a 0-10 scale). Two periods of cloudiness can be distinguished during the year: a cool period and a warm period (from March to October). The latter one is characterized by significantly lower but a more diverse degree of cloudiness. The least cloudy month is August and the most cloudy--December. Seasonally, most sunny hours are recorded in summer, accounting for 40% of the total annual insolation. The distribution of the average yearly air temperature in the area of the study area is not homogenous, but there is a general tendency toward decrease in temperatures from the west to the east. The central and eastern parts of the Lublin Voivodeship are thermally monotonous. Air temperature annual values over the studied area are typical for the general thermic conditions in Poland. The highest mean monthly air temperatures are recorded in July and amount to about 17.2 \({}^{\circ}\)C, whereas the lowest ones, of _ca._ -4.3 \({}^{\circ}\)C, are recorded in January. Frosty days in the study area are noted from November to March and only sporadically also in August and October. The vegetation period in the eastern and central part of the Lublin province lasts 211 and 214 days, respectively. The number of hot days (with the mean air temperature exceeding 25 \({}^{\circ}\)C) ranges between 28 and 37 on the average, and that of very hot days (over 30 \({}^{\circ}\)C) equals 4, on average. Annual mean total precipitation varies from 580 to 600 mm. Changes in the mentioned above climate characteristics in the last 40 years are provided in [22]. Our measurements were carried out at 11 research sites (Figure 1, Table 1) situated in forest areas and in open areas adjacent to them. Each research site comprised an area of approximately 0.5 ha, and within this area LAI measurements and herpetological surveys were conducted (see Sections 2.2 and 2.3). The sites have been selected on the basis of reptile population surveillance in the area of the Solska Forest and its neighborhood since 2008 [23], and they represent various habitats comprising forests, open areas and mixtures of both. Six of our research sites (BM, Buko, Edg, Frz, Wbag and ZP) are located in the Solska Forest, on the Sandomierska Basin; four sites (Bor, Dom, Joz and Krl) are located in the Roztocze National Park area and its protection zone; and one site (Roj) is located on the Roztocze National Park and the Sandomierska Basin boundary, but outside the Solska Forest (Figure 1). At present, nine reptiles representing two orders--turtles and squamata--are found in Poland. Squamata reptiles are subdivided into two suborders: lizards, represented by 2 genera and 4 species; and snakes, represented by 4 genera and 4 species.