Utilization of Phenological Observation in the Landscape Mapping with using GIS

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1 Utilization of Phenological Observation in the Landscape Mapping with using GIS Ales Vavra, Lukas Marek Department of Geoinformatics Palacký University Olomouc 17. listopadu 50, Olomouc Czech Republic Abstract: The paper is focused on comprehensive approach to phenological mapping of the landscape and integration with other technology of data collection. The aim of research is practically verify by the possibility of integration of several methods of data collection in the study of the landscape heterogeneity. The experimental area is the location of Vysoké Pole in the South-east part of Czech Republic. In this area is observed phenological activity of selected plants at several different periods. Results from this observation are compared with other results from small-format photography and results from monitoring using sensor networks. All results are integrated and can be used in following analysis. Outputs from this analysis are maps, models, static time series and trends of selected biotic factors (for example biomass, chlorophyll, foliage area). From this can be derived predictive models of area conditions. Key-Words: Phenology, landscape mapping, phenological observations, sensor network, small-format aerial photography, GIS analysis, NDVI index 1 Introduction Climate change over the last two decades has greatly increased the importance of global environmental study. In contrast, the local landscape mapping has great importance in monitoring changes in smaller areas. The landscape mapping is the process of creating n- dimensional model of a particular landscape most in form of maps - based on the use of cartographic means of expression and respecting the principles of cartographic representation [1]. Product of mapping of landscape - landscape map is a representative model of the vertical and horizontal structure of interest territory as a condition for the occurrence and progress of specific states and processes. The landscape consists of its individual components and natural creations of human. These are functionally linked and interdependent. During mapping of landscapes are taken into account all of its structural components. These folders are not mapping their own, as do the partial geoscience disciplines, but integrated or interconnected as in reality and in the real landscape. There are offer three main ways to landscape mapping. First is field mapping based on prior knowledge of the analytical component maps (geological, soil, landuse etc.). Second is a laboratory analytical integration by the component materials methodological procedures of physiographic regionalization with subsequent control in the terrain. Third is a distance mapping is the definition of landscape units based on remote sensing images with using of prior knowledge of the analytical component maps (geological, soil, landuse etc.) with subsequent control in the terrain [1]. 2 Phenological observation and mapping Phenology is the science dealing with the study of the time course of periodic live signs of developmental stages of plants (and animals). Also study of the relationships of these phenological phases on climatic and soil conditions during individual years [2]. The essence of the phenology is monitoring of phenomena in nature that occur annually, but to varying periods or with a different intensity, as they reflect time-varying of environmental conditions. Phenological phases (or phenological stages) are a well externally recognizable, usually annually repetitive process of visible organs of higher plants [3]. The phenological observations obviously used to identify relationships and vegetation responses to the ongoing change of climatic conditions and its ISBN:

2 response to significant weather events in different years. Phenological phenomena to some extent describe the features of the climate of different scale (from macroclimate to microclimate), as are the product and reflection of climate. Long series of phenological observations may serve to study of climate variability because trends of onset of phenophases correlate with trends of air temperature and. This can be observing also reverse. On this basis, it can perform phenology mapping of landscape. Phenological observations and research tend to have a different purpose, according to which the observed objects are selected and their habitats. Observations may relate to one or more plant species in close and diverse habitats, or in contrast observe to similar but more farer locations [4]. By the recognition of phenology stages, we can possible capture different climatic nature of large forest areas, determine the length of time of the production of trees and on this basis to define natural areas and regions for forest. Monitoring phenological phases can help the organization of growing of culture plants and the fight against pests, increase seed production and forest products. Phenological observations performed even crops, which can then be used for example in the study of the influence of temperature and other climatic conditions of habitats and to determine the characteristics of the agrometeorological conditions [4]. of selected biotic factors (for example biomass, chlorophyll, foliage area) can be prepared for predictive modelling of phenological conditions of the studied area. The expected results of observations show the different conditions in the development of vegetation on sites caused by elevation, slope, aspect or terrain topography. 4 Experimental Site Experimental site is the location of the Vysoké Pole village. The location lies at an altitude of 423 m, about 7 km northwest of the town Valašské Klobouky, Zlín Region, Czech Republic. The total land area is of 1,211 hectares. Of which ha is arable land, gardens are 15 ha, 14 ha are orchards, permanent grassland is 271 ha, 591 ha is forest land, water area is 6 hectares, built-up area is 13 ha and other areas 56 ha. The village operates with EnviCentrum that focuses on environmental education and management as the main creator of the local landscape. It is also focused on the individual components of the landscape, their dynamics, the relationship between the state of the environment and human particular economic activity. Department of Geoinformatics has cooperated with EnviCentrum more than two years, and forms the basis of experimental site of department here. In its vicinity are also some of the sensors deployed by members of department. 3 Aims of research The research is focused on comprehensive approach to phenological mapping of the landscape and integration with other technology of data collection. The aim of research is to practically verify integration of several methods of data collection in the study of heterogeneity of the landscape. These methods include: 1) landscape remote sensing provided by unmanned aerial vehicle 2) monitoring of abiotic factors by network of sensors 3) observations of phenological development of wild plants and 4) GIS analysis of digital elevation model of the site. The studied area is the Vysoké Pole experimental site where phenological activities were observed in several different periods. The observation is compared with results from small-format photographing and from sensor network monitoring. All results are integrated for further analyses. The final results in form of static time series and trends Fig. 1: Localization of experimental site within Czech Republic 5 Methods Heterogeneity of the landscape is usually defined by temperature conditions, the structure and condition of vegetation. From previous studies [5, 6, 7] it is clear that the used scale plays an important role the in the study of heterogeneity of landscape. And especially if they are results further used for local phenological studies. In this case, data from satellite ISBN:

3 images are useless for its small scale. And it is good to look for solutions in small-format photography, which provides data in the large scale. To verify these data can be used land sensor networks. With proper placement and continuous monitoring results can be considered very well [8]. Statistical evaluation of these results is the last step that can be used for the evaluation of results. 5.1 Method of phenological mapping of landscape The project utilizes the method of phenological mapping of landscape. This method is relatively less known, the ratings of phenological development of plants are compared with seasonal development of plant communities in selected habitats. This method was first proposed by Ellenberg in 1954 [9]. Its advantage is mainly in collection of a relatively large amount of data during a single season or observation, which is necessary due to the temporal availability in the project. Observation can be able to perform even a single observer. The advantage is the avoidance of differences subjective observation of more observers [10]. Phenological observations can be then expressed in phenoclimatic maps, because they are in direct connection with meteorological, respectively climatical influences. Using them can be express different onset of vegetation phase on plants in the monitored sites, depending on climatic conditions. Data obtained from phenoclimatical analysis will then be used to create predictive models of landscape [11]. These can be used to predict a local behavior and changes in microclimate habitat. It can be valuable for the protection of nature or procedure to predict the spread of invasive species of plants and animals (e.g., pests) or selection of suitable site for successful reintroduction. In connection with this method of measuring the air temperature using of sensor on the observed habitat, it is tested usability of detailed phenoclimtological maps as maps of temperature. The crucial characteristic for evaluation of onset of phenophases in spring can be considered the sum of effective temperatures. If temperatures are monitored using of the sensors, it is possible from single phenological observation to quantify the amount of temperature required to achieve different phenophases. All observed phenological information therefore lead together with data obtained from or small-format imaging sensors measured to derive the detailed phenoclimatical characteristics of territory which is usable in terms of application to other analyzes and decision-making processes. 5.2 Other used methods of data collection and processing Another methods and technologies of data collection and processing are used in the research. Results collected by these methods can be combining with phenological mapping of landscape. These methods are: 1) Landscape remote sensing provided by unmanned aerial vehicle it be focused on developing advantages of small-format aerial photography in spatial and radiometric accuracy domain. Paraglider model DRONE PIXY is used in the research with aim of acquiring vertical or oblique photographs at regular intervals. These images serve as a large data base for further spacetime analysis [12]. Images are acquired in the visible and near infrared spectrum. Health status of vegetation and soil moisture parameters can be determined from subsequent image processing. Highly accurate and detailed digital surface model (DSM) and a digital terrain model of relief (DTM) of area of interest can be extracted from stereo images taken by model from small height [13]. 2) Monitoring of abiotic factors by network of sensors continuous monitoring of abiotic factors using sensor networks covers the need of calibration and verification data acquired by spectrozonal aerial imagery and data acquired from interpolation and prediction models. This will be achieved by using sensors, data loggers and wireless sensor networks in the field. The data are finally transmitted into a central database. 3) GIS modelling and data processing - includes the creation of accurate digital surface models and digital terrain model from stereo images captured by Pixy model. Activity also includes processing of data from continuous monitoring of climatic factors. The vegetation indices can be counted from spectrozonal images. Primarily point data from the sensor stations are interpolated to describe the behaviour of individual climatic factors in the whole area. 4) Visualization - focuses on continuous visualization of the final results and final treatment outcomes. Expected outputs of visualization can be: digital surface model, a detailed digital terrain model, a set of orthogonal and oblique images with high spatial resolution taken at regular intervals in the visible and near infrared spectrum, time series geodata of selected abiotic factors (air temperature, soil temperature, air pressure, humidity, soil moisture), time series geodata of selected biotic factors (biomass, the amount of chlorophyll, the area of foliage), predictive models of site conditions, the correlation between habitat ISBN:

4 conditions and vegetation status, professional publications and specialized maps. 6 Current phenological observations Phenological observations on the experimental site were conducted from June to October. At the beginning it was important to determine the location and the species to which it will be carried out observations. Choosing the right sites was determined by several factors. Localities have had similar conditions, but had to be located at different altitudes. Distance of the sites could not be too small to avoid the same observation. It had to be selected representative species. The selection of sites and species were used with help of phenological observation methodology developed at the Czech Hydrometeorological Institute (CHMI). All selected sites are located in the experimental area and also near the location of sensor networks. They are also very well observable for small-format photography. This ensured the condition that the sites will be observed by several different methods of monitoring. Finally, they were selected two main sites and one backup location. Selected sites were mapped in detail and were found all the important parameters. The observed species locations were selected oak, beech and pine. For these species are determined individual obtained phenological stages according to the methodology CHMI. The phenological observations. A brief summary of the observations of beech at the site 1 is available in the attached Table 1. Tab. 1: Selected observations of beech Site 1 Date June 11 July 16 August 1 September 3 Vegetative Phenophase fully leaved (100 %) fully leaved (100 %) fully leaved (100 %) herb sprout begin to lignify (10 %) Generative Phenophase bud creation (10 %) bud creation (10 %) first fruit visible (10 %) first fruit visible (10 %) 7 Outputs and Conclusion After evaluation of phenological observation follow the processing of results gained with using of other methods. Images taken from small-format photography tools are processed. From stereo images taken from unmanned model is created part of digital terrain model (DTM) of the experimental site. Complete Fig. 2: Digital terrain model created based on laser scanning data observations were carried out in regular intervals. The actual observation was also made using photographs. This made it possible to consult the current status of the plants with experts on the DTM of monitored area (see figure 2) is then created based on data from laser scanning that was purchased by the Department of Geoinformatics. Model from stereo images was also used to check ISBN:

5 the accuracy of the model from the laser scanning. From the multispectral images are compiled mosaics of two monitored sites with a predominant orientation (southwest and southeast). Subsequently, the vegetation indices are calculated by expressing the ratio between the amounts of reflected radiation in the near infrared part of the spectrum and red part of the electromagnetic spectrum. As the most representative index is selected vegetation index NDVI. For all periods and locations were created images (maps) with NDVI values. At the same time is made a comparison with data obtained from the sensor network. The primary point data from sensor stations (air temperature, precipitation, soil moisture, irradiace) were interpolated to describe the behavior of individual climatic elements throughout the area of interest. Together with the data of terrain slope and aspect in the experimental site was created detailed characterization of heterogeneity of habitats. To define the relationship between the results of phenological mapping and data from the sensor network (in particular air temperature) were calculated sum of effective temperatures, since this characteristic is decisive for the assessment of the onset of different phenological stages. The output is a map of the distribution of sum of effective temperatures resulting spatial interpolation of measured values. These values are then entered into the analysis of average deviations onset of selected phenological stages. This analysis is visualized in the same synthetic map. At the end are derived two maps of entries selected phenological stages (of species of oak and pine forest). To compare of results the statistical tools is used. Correlation analysis is used to assess the existence and tightness of relations between biotics and abiotic factors (air temperature, irradiation, humidity, soil moisture, amount of biomass) and NDVI index obtained from images. When comparing the images from the site can be observed a clear correlation between growing season and the value of the NDVI index. NDVI index closely correlates with the amount of biomass in vegetation. Index can have maximum values of 1. In the growing season and full ripeness of vegetation, NDVI values moving at the maximum value approaching 1. On the contrary, in September is already quite apparent downward trend of the index value. Among the sites 1 and 2 are observed differences in NDVI index. Different slopes orientation has a significant effect on the amount of biomass in the area. Slope areas with a southeast aspect have higher values of NDVI index than insolate location with southwest orientation. It is caused by greater insolation in southeast. During analyzing of the data, it is found that the slope which is oriented of southeast. Direction contains a higher percentage of the NDVI index declining to less than 1 then less sunlit slope. This is true for all months in which images were carried out. It can be said that the heterogeneity of the surface has a significant effect on the amount of biomass in the locality. For a more accurate result of the total amount of biomass were selected two experimental squares of side length 1 m. Images from squares were taken by multispectral camera (see figure 3) and the calculated average NDVI index for the square. After taking images was all the vegetation mowed. The fresh vegetation was weighed on an accurate digital scale. Mown vegetation was dried in a special oven and then weighed again. Different values in the weight of vegetation again correlate with the amount of biomass. Fig. 3: Images of squares of vegetation for verification of biomass amount captured by multispectral camera Visualization of results will take place after the evaluation of the results. The first task is visualization of partial results of individual activities in the form of images, graphs or tables; the second task is overall results visualizations used for their presentation in form of specialized maps. Visualization of results is just as important as its other parts: because without a quality and accessible visualization can sufficiently informed about the results. Our research has focused on obtaining data from the landscape by different methods of collection. Phenological observation as one of the method in the landscape mapping can be very perspective, especially for monitoring of changes in landscape processes in the smaller localities. ISBN:

6 Acknowledgement The authors gratefully acknowledge the support by the Operational Program Education for Competitiveness - European Social Fund (project CZ.1.07/2.3.00/ of the Ministry of Education, Youth and Sports of the Czech Republic) and project "The small format aerial photography in the study of the effect of surface heterogeneity on the habitats" (project number _2012_007) with the support of Internal Grant Agency of Palacky University in Olomouc. References: [1] Kolejka, J., Krajinné mapy a jejich klasifikace, Geodetický a kartografický obzor, Vol. 45/87, No. 87, 1999, pp [2] Nekovář, J., Hájková, L., Fenologická pozorování v Česku historie a současnost, Meteorologické zprávy, Vol. 63, No. 1, pp [3] Nekovář J., Rožnovský J., Fenologická služba ČHMÚ. In: Rožnovský J., Litschmann T., Vyskot I. (ed.), Fenologická odezva proměnlivosti podnebí. Brno, [4] Krška, K., Bioclimatological research in Moravia and Silesia from its beginning until 1945, Moravian Geographical Reports, Vol. 11, No. 2, 2003, pp [5] Chytry, M., Tichy, L., Phenological mapping in a topographically complex landscape by combining field survey with an irradiation model, Applied Vegetation Science, Vol. 1., No. 2, 1998, pp [6] Müller-Westermeier, G., Production of phenological maps in Germany. In: Spatial interpolation in climatology and meteorology. Luxemburg, [7] Jeanneret, F., Rutishauser, T., Phenology for Topoclimatological Surveys and Large-Scale Mapping. In Hudson, I. L., Keatley, M. R. (eds.): Phenological Research - Methods for Environmental and Climate Change Analysis, Springer, 2008 [8] Pechanec, V., Vavra, A., Hovorkova, M., Brus, J., Kilianova, H., Analyses of Moisture Parameters and Biomass of Vegetation Cover in South East Moravia, International Journal of Remote Sensing, (in press) [9] Vymazalová, M.: Čím mohou podrobné fenologické mapy území s členitým reliéfem přispět bioklimatologickému výzkumu?. In Rožnovský, J., Litschmann, T. (ed): Bioklimatologické aspekty hodnocení procesů v krajině, Mikulov, [10] Otypkova, Z., Chytry, M., Tichy, L., Pechanec, V., Jongepier, J. W., Hajek, O., Floristic diversity patterns in the White Carpathians Biosphere Reserve, Czech Republic, BIOLOGIA, Vol. 66, No. 2, 2011, pp [11] Pechanec, V., Vavra, A., Svobodova, J., Mirijovsky, J., Phenological analysis of the landscape with the support of geographic information technologies, Conference Proceedings SGEM 2012, Vol. II, 12th International Multidisciplinary Scientific GeoConference SGEM, 2012, Sofia, pp [12] Mirijovsky, J., Brus, J., Pechanec, V., Utilization of a small-format aerial photography from drone pixy concept in the evaluation of the landscape changes, Conference Proceedings SGEM 2011, Vol. II, 11th International Multidisciplinary Scientific GeoConference, 2011, Sofia, pp [13] Svobodova, J., Mirijovsky, J., Kilianova, H., The peculiarities of the digital surface model creation from the data acquired by small format photography, Conference Proceedings SGEM 2012, Vol. III, 12th International Multidisciplinary Scientific GeoConference SGEM, 2012, Sofia, pp ISBN: