Research of the Biodiversity of Tovacov Lakes
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Research of the biodiversity of Tovacov lakes (Czech Republic) Main researcher: Jan Ševčík Research group: Vladislav Holec Ondřej Machač Jan Ševčík Bohumil Trávníček Filip Trnka March – September 2014 Abstract We performed biological surveys of different taxonomical groups of organisms in the area of Tovacov lakes. Many species were found: 554 plant species, 107 spider species, 27 dragonflies, 111 butterfly species, 282 beetle species, orthopterans 17 and 7 amphibian species. Especially humid and dry open habitats and coastal lake zones were inhabited by many rare species. These biotopes were found mainly at the places where mining residuals were deposited or at the places which were appropriately prepared for mining by removing the soil to the sandy gravel base (on conditions that the biotope was still in contact with water level and the biotope mosaic can be created at the slopes with low inclination and with different stages of ecological succession). Field study of biotope preferences of the individual species from different places created during mining was performed using phytosociological mapping and capture traps. Gained data were analyzed by using ordinate analyses (DCA, CCA). Results of these analyses were interpreted as follows: Technically recultivated sites are quickly getting species – homogenous. Sites created by ecological succession are species-richer during their development. Final ecological succession stage (forest) can be achieved in the same time during ecological succession as during technical recultivation. According to all our research results most biologically valuable places were selected. Appropriate management was suggested for these places in order to achieve not lowering of their biological diversity. To even improve their biological diversity some principles and particular procedures were formulated. Also principles and procedures ensuring attractive environment for plant and animal species were formulated. Introduction High capacity mining of sandy gravels by floating excavators usually means very strong and distinct intervention to the landscape. There are many points of view on this activity. Biological point of view is one of the most important ones. Biodiversity is really important landscape-creative element because landscape character is very strongly connected also with life quality of people. The question consequently is if mining in certain area is able to support biodiversity of landscape and which interventions and technological processes are crucial. Other important question is if supported and raised biodiversity is possible to manage although mining is finished. Then we need to decide which type of recultivation is the best to support the goal of raised biodiversity. Biological parameters of specific mining locality need to be known first. Objectives Our study area is still changing due to continual mining. There is a possibility to create biological interesting biotopes in places where active mining and material manipulation take place. Already mined places can be gradually enhanced for occurrence of rare species and for recreation. This high potential of such localities was and is not utilized yet. Provision of information to improve current situation is our main objective. This study is focused on biodiversity research and support in the area influenced by mining. We used following methods: (1) inventory surveys of chosen taxonomical groups of organisms and (2) field study of biotope preferences of individual species. On the basis of obtained data it will be possible to identify (3) rare species occurring in our study area and (4) rare biotopes. For that biotopes appropriate management ensuring not lowering of their biological values will be suggested. (5) Adjustments of some technological processes will be proposed according to our findings. Background information The region between municipalities Tovačov and Troubky lies in the river Morava basin. This area is called “Haná” and it is located in the Middle Moravia in the east part of the Czech Republic. The region is typical by quite warm climate, optimal precipitation amounts and high-quality soils. Natural and semi-natural habitats rich in biological diversity of plant and animal species existed here in the past till now. Consequently local high- quality soils were used for intensive agriculture and the amount of natural habitats decreased a lot. Remains of riparian forests can be still found here but subsequent meadows and wetlands were strongly reduced during last decades. All these changes caused decline and reduction of many populations belonging to different groups of organisms. 1 In the area of Tovačov lakes sandy gravel have been mined largely since the fifties of the 20th century. The system of four lakes was created varying in age and depth. The majority of lakes have already firmed banks which were technologically recultivated in the past (by evening the terrain out and its afforestation or grassing over). However some places (especially majority area of the island among lakes I, III and IV) were left for ecological succession. Generally, our study area is part of vast wetland region (obr. 1). Tovačov region (357 ha) and Troubky region (149 ha) comprise mostly of the area of lakes (70 %). Local relief is quite plane ranging between 191 – 210 metres above sea level. This region is biologically valuable which is also supported with categorization of the lakes I, III and IV into Special Protection Area (SPA Morava – Chropyňský luh – EVL CZ 0714085). Although the only subject of official protection according to Natura 2000 is the European beaver (Castor fiber). The locality is also rich in birds but the diversity of other organisms is not very well known yet. Social importance of this locality should not be neglected. Lake III is favourite fishing and diving territory and is also used for recreation by local people. Lakes I and II are drinking water reservoirs. Methods Inventory surveys Fieldwork took place from 26th of March to 23rd of September 2014 and consisted of 25 botanical visits and 33 zoological visits. Detailed inventory surveys of main taxonomical groups of bioindicating organisms were performed (vascular plants, beetles, spiders, amphibians, reptiles, daily butterflies, dragonflies). Other organism groups were not systematically mapped because of sufficient knowledge about it and because of other ongoing projects (for example birds). These organisms were just written down if they were spotted. To exactly describe the environmental variability and to specify floristic and faunistic records our study area was divided into partial sites. These partial sites were created by combining different site ages, succession types, the way of site origins and different vegetation cover. Partial sites for particular taxonomical groups were consequently adjusted (Fig. 2, Fig. 3). Programs Janitor (2.6.4.) [65] and QGis 2.4. [70] were used to process GPS data gained during the field work by GPS machine Garmin eTrex 30. Map sources are from Geoportal Cenia [64]. GPS coordinates are given in WGS 84 format. All biotope mapping was done according to the Habitat Catalogue of the Czech Republic [1] and Manual evaluation of habitat [2]. Borders among specific biotopes at the actual orto-photo picture were defined straightly in the field. To identify biologically valuable places standard deviations of their approximate values were established [3]. Floristic inventory survey was done according to standard floristic methods placing emphasis on recommendations in Methodology inventory survey of specially protected areas [4]. Documentary plant material was collected, prepared and preserved by standard methods [5] and is located in herbarium of the Department of Botany of Palacky University in Olomouc (OL, [6]). Literary survey of available floristic databases was done [7, 8, 9, 10, 11]. Bryophytes were studied just briefly at the uncovered sites to compare it with natural bryophyte communities at the eroded river Morava banks nearby. Animals were studied by using individual collecting, beating the vegetation, sweeping, sieving, light trapping, bait trapping and pitfall traps (plastic cap filled with saturated solution of salt and vinegar buried in the ground with its rim at surface level). All collected animals and animal material is deposited in the private collections of the researchers – F. Trnka (Coleoptera), O. Machač (Arachnida) and V. Holec (Lepidoptera and Odonata). Dragonflies were studied by recording of exuvia, mature individuals (M for males, F for females), immature individuals (Imm for new-born individuals) and epigamic behavior (T for tandem, O for oviposition). If exuvia were found the population was considered to be indigenous. If immature individuals were found and if epigamic behavior was observed the population was considered to be likely indigenous [12]. Concerning butterflies daily ones were recorded in the first place (Papilionoidea group, Hesperioidea group and the family Zygaenidae). Also some big nocturnal butterflies were recorded (Cossoidea, Lasiocampoidea, Bombicoidea, Drepanoidea, Geometroidae and Noctuoidae group) at the locality “island”. Amphibians were studied during night and day time visits by voice recordings, capturing to the nets and into the bait traps. Sites used as places for amphibian reproduction were systematically searched. The categorization of threat (further just RL as Red list) were used: for vascular plants from the Checklist of vascular plants of the Czech Republic [13], for