Ecological Units Research Articles

Differential predation by age and sex classes in blue wildebeest in Serengeti: study of a modern carnivore den in Olduvai Gorge (Tanzania).

Age and sex selection of prey is an aspect of predator ecology which has been extensively studied in both temperate and African ecosystems. This dimension, along with fecundity, survival rates of prey and mortality factors other than predation are important in laying down the population dynamics of prey and have important implications in the management of species. A carnivore den located in the short-grassland ecological unit of the Serengeti was studied. Sex- and age- class (using five age categories) of the wildebeest remains recovered were analyzed through horn morphology, biometrics of the bones and tooth wear patterns. We compared our results with previous studies from lion and hyaena kills through multivariate analyses. Seasonality of the accumulation was analyzed through tooth histology. PCA and CVA results show that age class selection by predators depends on season, habitat-type, and growth rate of the wildebeest population. Female-biased predation was found to contradict classical hypotheses based on territorial male behaviour. The lion and spotted hyaena showed strong selection on age classes, contrary to previous studies. Migratory wildebeest sex ratio is regulated through differential predation by seasons and female deaths in the wet season are a trade-off for population stability. These data are crucial for an effective management of the species and the new method created may be useful for different carnivore species and their prey.

Morphological and Phylogenetic Characterization of New Gephyrocapsa Isolates Suggests Introgressive Hybridization in the Emiliania/Gephyrocapsa Complex (Haptophyta)

The coccolithophore genus Gephyrocapsa contains a cosmopolitan assemblage of pelagic species, including the bloom-forming Gephyrocapsa oceanica, and is closely related to the emblematic coccolithophore Emiliania huxleyi within the Noëlaerhabdaceae. These two species have been extensively studied and are well represented in culture collections, whereas cultures of other species of this family are lacking. We report on three new strains of Gephyrocapsa isolated into culture from samples from the Chilean coastal upwelling zone using a novel flow cytometric single-cell sorting technique. The strains were characterized by morphological analysis using scanning electron microscopy and phylogenetic analysis of 6 genes (nuclear 18S and 28S rDNA, plastidial 16S and tufA, and mitochondrial cox1 and cox3 genes). Morphometric features of the coccoliths indicate that these isolates are distinct from G. oceanica and best correspond to G. muellerae. Surprisingly, both plastidial and mitochondrial gene phylogenies placed these strains within the E. huxleyi clade and well separated from G. oceanica isolates, making Emiliania appear polyphyletic. The only nuclear sequence difference, 1bp in the 28S rDNA region, also grouped E. huxleyi with the new Gephyrocapsa isolates and apart from G. oceanica. Specifically, the G. muellerae morphotype strains clustered with the mitochondrial β clade of E. huxleyi, which, like G. muellerae, has been associated with cold (temperate and sub-polar) waters. Among putative evolutionary scenarios that could explain these results we discuss the possibility that E. huxleyi is not a valid taxonomic unit, or, alternatively the possibility of past hybridization and introgression between each E. huxleyi clade and older Gephyrocapsa clades. In either case, the results support the transfer of Emiliania to Gephyrocapsa. These results have important implications for relating morphological species concepts to ecological and evolutionary units of diversity.

Identification of agricultural soils suitable for afforestation in the Czech Republic using a soil database

Afforestation of agricultural lands may be a positive action in many cases. Especially, it is a beneficial feature for waterlogged soils, stony soils or for soils which are less fertile for any other reason and thus unsuitable for farming. Afforestation can be a very important action even in the agricultural landscape – afforested belts of agricultural land divide large farm blocks into smaller ones, or act as windbreakers and biological corridors. The value, quality and fertility of soil can be assessed in different ways. The study aims to determine the identification soil criteria of agricultural land which is suitable for afforestation. This evaluation process is based on Evaluated Soil Ecological Units (ESEU), in the Czech Republic known as BPEJ, database which is available for all agricultural land in the Czech Republic. The results are represented by a complete list of ESEU codes suitable for afforestation. The list of codes is supplemented by an explanation why such an ESEU code, representing a soil group with similar properties, is suitable to afforestation.

Analysis of operational approach during forest transformation in Klokočná Range, Central Bohemia

Afforestation of agricultural lands may be in many cases a positive step. Especially, it is a beneficial with waterlogged soils, stony soils or for soils which are for any other reason less fertile and unsuitable for farming. Even too in the agricultural landscape, afforestation can be very important by the breaking of large farm blocks by windbreakers and bio-corridors. The value, quality and fertility of soil can be assessed in different ways. The aim of this study is to determine the criteria for the identification of agricultural land suitable for afforestation. This evaluation process is based on Evaluated Soil Ecological Units (BPEJ) that are publicly available and already processed for all agricultural land. The results are represented by complete list of Evaluated Soil Ecological Units that are suitable for afforestation with stating the reason why they were chosen.

Time for change: The legacy of a Euro-Andean model of landscape versus the need for landscape connectivity

The extreme social–ecological diversity and human use of tropical mountains has led to the development of complex and globally influential models of humanized landscapes. At the same time, such regions are increasingly subject to challenges from new global socioeconomic and environmental changes. This study investigates the role of landscape models amid new social–ecological challenges in the Andes of western South America. Research is focused on the Andean valley-upland landscape model that emerged in the early colonial period (1550–1750), and its long-lasting legacies. This model drew on the hybrid Euro-Andean landscape knowledge forged in contexts of landholding institutions, urbanization, and demographic and climatic change of the early colonial period. It is examined here through multi-dimensional sources ranging from Chronicles; indigenous texts and maps; colonial laws; imperial Geographic Reports; sanctioned Inspections; demographic and land use changes; impacts of Little Ice Age climate change; historical cartography; and landholding litigation documents. Andean valley basins were treated as fixed sites of Spanish control and private property, whereas uplands featured fugitive qualities. The valley-upland landscape model thus exemplified a binary and relational territorial logic of settled/unsettled that contributed to the colonial dispossession of indigenous lands. Its powerful legacy is a major counterpoint to environmental interpretations of European conquest and colonialism such as pristine myth debates. Today the valley-upland model is notably incongruous with expanding needs for landscape connectivity and sustainability. Its emphasis on spatial distinctness and separateness is at odds with current challenges, especially climate change, that require enhancing connectivity to strengthen resilience across social–ecological units.

What Is Speciation?

What is a species? What is speciation? These questions are not easy to answer. Yet, for those microbiologists studying environmental questions or dealing with clinical issues, the ability to name and recognize species, widely considered the fundamental units of ecology, can be useful as well as being fundamentally valuable. The speciation problem, the focus here, is more mechanistic and conceptual. What is the origin of species, and what evolutionary and ecological forces keep them separate once they begin to diverge?

Transforming Parent-Child Interaction in Family Routines: Longitudinal Analysis with Families of Children with Developmental Disabilities.

The efficacy and consequential validity of an ecological approach to behavioral intervention with families of children with developmental disabilities was examined. The approach aimed to transform coercive into constructive parent-child interaction in family routines. Ten families participated, including 10 mothers and fathers and 10 children 3-8 years old with developmental disabilities. Thirty-six family routines were selected (2 to 4 per family). Dependent measures included child problem behavior, routine steps completed, and coercive and constructive parent-child interaction. For each family, a single case, multiple baseline design was employed with three phases: baseline, intervention, and follow-up. Visual analysis evaluated the functional relation between intervention and improvements in child behavior and routine participation. Nonparametric tests across families evaluated the statistical significance of these improvements. Sequential analyses within families and univariate analyses across families examined changes from baseline to intervention in the percentage and odds ratio of coercive and constructive parent-child interaction. Multiple baseline results documented functional or basic effects for 8 of 10 families. Nonparametric tests showed these changes to be significant. Follow-up showed durability at 11 to 24 months postintervention. Sequential analyses documented the transformation of coercive into constructive processes for 9 of 10 families. Univariate analyses across families showed significant improvements in 2- and 4-step coercive and constructive processes but not in odds ratio. Results offer evidence of the efficacy of the approach and consequential validity of the ecological unit of analysis, parent-child interaction in family routines. Future studies should improve efficiency, and outcomes for families experiencing family systems challenges.

Ecosystem services based spatial planning decision making for adaptation to climate changes

Climate change adaptation is a rising global issue and has become the primary issue for transnational organisations and EU institutions. Particularly in developing and dynamic cities like Istanbul, the pressure of rapid urbanisation, institutional and legislative uncertainties are expected to create new vulnerabilities in ecosystems and their services. Climate change can cause new vulnerabilities in ecosystem services (ESs) through events such as floods, heat-waves, and droughts brought on by rises in temperatures and changes in precipitation. These vulnerabilities may affect the well-being of inhabitants and interfere with the reaching of sustainable development goals in the future.Istanbul has a unique geographical location for biological diversity when compared with other settlements in the region, and the urban development dynamics of the region play a significant role in the well-being of ecological units and biological diversity of the Istanbul Metropolitan Area (Özhatay, Byfield, & Atay, 2003; Tezer, 2005; Tezer et al., 2008). This paper aims to define which ESs are vulnerable due to both LCLU change caused by urbanisation and potential impacts of climate change. Particular importance is given to the result of the survey done with related stakeholders as it is used to define and to verify the existing and future vulnerabilities of ESs in Istanbul. Regarding the close relationship between ESs and LCLU, the impact of changes in LCLU on key ESs are evaluated by developing LCLU scenarios. Climate change scenarios are used in this paper to understand the possible future climatic conditions of Istanbul and their impact on LCLU and ESs. These two sub-results are prepared according to scenario analyses and are evaluated together to address the future vulnerabilities of ESs. Integration of ESs and climate change adaptation strategies into spatial planning (EEA, 2010) seems to be both necessary and urgent. Therefore, a spatial planning framework that is climate change adapted and ESs oriented is proposed as a key tool to achieve a climate resilient, sustainable development in Istanbul. The framework used in this paper can be used to develop relevant strategies and planning tools by considering climate change adaptive policies for other rapidly developing settlements.In brief, this paper aims to integrate ecosystems and their services into spatial planning by using relevant mapping of ESs, which will be utilised for the climate adaptive spatial policy development process for the Istanbul case. This paper has been prepared under the auspices of The Scientific and Technological Research Council of Turkey (TUBITAK) Project No. 110K350.

Effect of Creative Drama on Academic Achievement: A Meta-analytic and Thematic Analysis

Creative drama implies that there is a teacher who facilitates the lesson by adding structured plays that often consist of beginning, middle, and conclusion. The method operates as a group process and it is effective because of its ability to strengthen a group and create a cohesive unit (Booth & Lundy, 1985; cited in Arieli, 2007). Creative drama includes improvisation, movement, and rhythms and is created on the spot, not memorized or scripted. Thus, a spontaneous self-expression of the participants comes into the scene (McCaslin, 1996). The students in the class act out a story they had learned before and this improvisational and spontaneous process enables them to further analyze and synthesize information creating personal meaning (Arieli, 2007; Guli, 2004). Creative drama includes students in concrete and applied practices of behavior as skills are physically and verbally acted out which results in an authentic experience for the participants (Bailey, 1997). In addition, Laurin (2010) suggested that the students and the teacher can go back and forth in creative drama and make changes as they wish. That is, the focus of creative drama is to be on participants' experience which indicates that creative drama is nonexhibitional and process centered.The outcomes of utilizing creative drama in learning environments can be beneficial as students who behave in a shy, quiet, or self-conscious manner often regain confidence after they learn to use their unlimited imagination. Knowledge and vocabulary that have been internalized through traditional teaching methods has an opportunity to be externalized in creative drama environments (O'Hara, 1984). Developmental psychologists explain that children explore the world and how to behave in it through imitation, symbolic plays, and dramatic plays. However, our educational system has yet to embrace this strong and natural learning method. Many teachers hesitate from applying creative drama as a teaching tool in the lesson because they think it will take too much time, energy, or effort. They may rationalize that it is a method that they are not familiar with and therefore cannot begin to master without a lengthy training process. In fact, the opposite is true; once you have learned how to do it, you never forget (Bailey, 1997).In the process of creative drama, participants may not necessarily become experts in a field, but instead, learn or develop certain skills as they engage in meaningful dramatized stories together (Guli, 2004). Especially in students' speaking skills, creative drama offers a valuable facility to practice and also increases motivation for students to express themselves (Shand, 2008). Creative drama provides active use of the senses, and thus addresses the issues related to Garden's multiple intelligences. That is, students learn through dialogue, movement, sound, and sight. Dialogue, role-playing, and kinesthetic movements appeal verbal-linguistic, spatial, bodily-kinesthetic, interpersonal, and intrapersonal intelligence styles. Creative drama, then, is a means for teachers to engage multiple learning styles in learning environments (Tate, 2002). Therefore, with this meta-analytic review, the effect of such a multi-functional method was investigated.The Aim and Significance of the StudyUsing creative drama for teaching has led many researchers to examine its effect on various fields or courses, one of which is conducted in seventh graders' science achievements in ecology and matter cycles unit. In this experimental study, the author found a statistically significant difference between the mean scores of groups in favor of the experimental group after treatment (Cokadar & Cihan-Yilmaz, 2010). In a quasi-experimental research study by Gundogdu (2012) the effect of a creative drama-based assertiveness program on students' assertiveness skills was studied. Following a period of a 10-week application, it was observed that the scores of the experimental group increased at a significant rate compared to those of the control group. …

Structural and productivity characteristics of montane beech forests in the area of Radava mountain

This paper presents a typological study of the ecological unit of mountain beech forests in the area of Radava mountain. The aim of this research is to present the basic characteristics of these forests ecosystems through the process of defining forest types. The results will help in defining the forest type and according to the results of this research will create conditions for a more realistic definition of goals in planning the management of these and other forest ecosystems.

Modeling Ecotourism Potentials of Karst Springs in GIS Environment: A Case Study of Rijab Mirage in Kermanshah Province, Iran

Mirages of Kermanshah province of Iran including Rijab mirage, with unique features such specific animal and plant species, very suitable climate , roaring waterfalls and etc. currently, as a ecotourism region is used by so Many people And has the capacity to become an ecotourism zone in the province and the country. In this research for feasibility of ecotourism development in mentioned area, first in the identification process, ecologically sustainable sources including vegetation cover, soil, geology and geomorphology has been identified And then in summarization and analysis step data obtained from the previous step, were processed and classified to enter in GIS environment; land surveying was conducted and then it combined with soil map and vegetation cover maps, ecological unit map, which is the base of ecological assessment, is obtained. Unsustainable resources such as water, climate and etc. were also considered.

SROVNÁNÍ METOD STANOVENÍ FAKTORU ERODOVATELNOSTI PŮDY K

The comparison of values of the soil erodibility factor K (which is used in the universal equation for soil loss calculation), that were determined according to the main soil units and values of the K factor determined on the base of texture analysis, has found differences in soil texture in the range of the same main soil unit. The need of the laboratory analyses follows from the comparative analyses for the determination of K factor that is also necessary for determination of threat of soil by water erosion or for the projection of erosion control. The values of K factor that was specified according to the soil ecological units could be possible to take as orientational ones.

Surveying the carbon pools of mountain soils: A comparison of physical fractionation and Rock-Eval pyrolysis

Accurate monitoring of soil organic carbon (SOC) pools with contrasted turnover times is necessary for better evaluation of the vulnerability of SOC stocks in the face of global changes. To obtain this information in heterogeneous landscapes such as mountain areas, fast and reliable approaches providing an assessment of SOC biogeochemical stability are needed. Recently, it has been shown that Rock-Eval (RE) pyrolysis enables a fast quantification of three SOC pools of different thermostabilities [Saenger, A., Cécillon, L., Sebag, D., & Brun, J.J. 2013. Soil organic carbon quantity, chemistry, and thermal stability in a mountainous landscape: A Rock-Eval pyrolysis survey. Organic Geochemistry 54, 101–114]. The aim of this study was to compare the RE pyrolysis method with the standardized and widely used technique of SOC physical fractionation for characterizing SOC pools at landscape-scale in a mountainous area of the calcareous French Alps. Physical fractionation revealed large quantities of particulate organic matter (POM, i.e. labile SOC) for all samples, suggesting an overall high vulnerability of mountain SOC stocks to environmental changes. Organic C stocks of mountain ridge topsoils (0–10cm) may be the most vulnerable with 76% consisting of POM, while alpine and subalpine grasslands developed on Cambisols presented more stabilized forms of SOC (64% of SOC stocks being associated with minerals, MaOM fraction). RE pyrolysis gave results similar to the physical fractionation method for the identification of stability patterns of the different ecological units and for estimating their dominant SOC pools (labile vs. stable). However, some discrepancies between the two techniques were observed for the absolute quantification of SOC pools, with slightly higher correlations between the physically and thermally derived stable SOC pool than for the labile pool (R2=0.59 and 0.50, respectively). These differences can be explained by the fact that each method has inherent biases and isolates somewhat different pools. Additionally, RE pyrolysis provided information about the chemistry of SOC pools, suggesting a greater maturity of SOC in the MaOM than in the POM fractions. Overall, this study confirms that the RE pyrolysis technique, being both time- and cost-effective, could become a standardized proxy for assessing SOC pools at landscape-scale although it requires further comparison with other methods for several soil and land-use types.

Research on Ecological Function Regionalization Based on the Ecological Service Function - Take Shenzhen River and Xinzhou River Estuarine Wetland for Example

The fundamental principles and methods of ecological function regionalization were defined in this paper based on field investigation in the estuarine wetland of Shenzhen River and Xinzhou River. The regionalization scope of the two rivers estuary wetland was delineated, and the main ecological service functions, such as climate regulation, water purification, material production, biodiversity conservation, wildlife habitats, education, recreation and tourism etc., were analyzed and summarized in accordance with the integrity of the eco-system and the administrative divisions status quo. According to the proposed regionalization principles and methods, the two rivers estuary wetland was divided into 6 ecological function units combined with its service functions and distribution characteristics, which were urban construction control area, terrestrial forest ecological belt, futian national mangrove reserves, mangrove restoration area, off-shore tidal flat reservation and estuary waters comprehensive treatment area. For each ecological function units, the leading service functions, Status quo and existing problems were elaborated, the ecological protection, repairation and restoration directions were pointed out, and the strengthening measures of ecological service function were put forward.

Predicting Brook Trout Occurrence in Stream Reaches throughout their Native Range in the Eastern United States

AbstractThe Brook Trout Salvelinus fontinalis is an important species of conservation concern in the eastern USA. We developed a model to predict Brook Trout population status within individual stream reaches throughout the species’ native range in the eastern USA. We utilized hierarchical logistic regression with Bayesian estimation to predict Brook Trout occurrence probability, and we allowed slopes and intercepts to vary among ecological drainage units (EDUs). Model performance was similar for 7,327 training samples and 1,832 validation samples based on the area under the receiver operating curve (∼0.78) and Cohen's kappa statistic (0.44). Predicted water temperature had a strong negative effect on Brook Trout occurrence probability at the stream reach scale and was also negatively associated with the EDU average probability of Brook Trout occurrence (i.e., EDU‐specific intercepts). The effect of soil permeability was positive but decreased as EDU mean soil permeability increased. Brook Trout were less likely to occur in stream reaches surrounded by agricultural or developed land cover, and an interaction suggested that agricultural land cover also resulted in an increased sensitivity to water temperature. Our model provides a further understanding of how Brook Trout are shaped by habitat characteristics in the region and yields maps of stream‐reach‐scale predictions, which together can be used to support ongoing conservation and management efforts. These decision support tools can be used to identify the extent of potentially suitable habitat, estimate historic habitat losses, and prioritize conservation efforts by selecting suitable stream reaches for a given action. Future work could extend the model to account for additional landscape or habitat characteristics, include biotic interactions, or estimate potential Brook Trout responses to climate and land use changes.Received May 9, 2014; accepted August 26, 2014

Using Test Site Analysis and two nearest neighbor models, ANNA and RDA, to assess benthic communities with simulated impacts

Reference Condition Approach bioassessment programs have been in place in the northern and Muskoka regions of Ontario, Canada, for many years. Assessments are carried out regularly to evaluate and monitor the effects of a variety of activities, including mining, forestry, and cottage development. These programs are run by the Co-operative Freshwater Ecology Unit (CFEU) at Laurentian University in Sudbury, Canada, and the Dorset Environmental Science Centre (DESC) in Muskoka, Canada. We applied 2 bioassessment methods used at the CFEU and DESC to 3 data sets that were subjected to simulated impact by nutrient enrichments to compare their performance with a number of other bioassessment methods. We used Assessment by Nearest Neighbour Analysis (ANNA) and a Redundancy Analysis (RDA) variation of ANNA with Test Site Analysis (TSA) to identify subsets of reference sites to compare with a given simulated impact test site based on habitat matching. We compared the benthic macroinvertebrate (BMI) communities and evaluated the differences between the validation and training sites to assess the degree of impairment. After assessing all impacted sites, we calculated Type 1 and Type 2 error rates. ANNA and RDA separated sites with different levels of simulated impact in an Australian data set of diverse benthic macroinvertebrate communities distributed along a habitat gradient. In contrast, our assessments did not perform well with 2 data sets for which the simulation did not behave as expected, perhaps because of impoverished communities.

Integrating the provision of ecosystem services and trawl fisheries for the management of the marine environment

The species interaction and their biological traits (BT) determine the function of benthic communities and, hence, the delivery of ecosystem services. Therefore, disturbance of benthic communities by trawling may compromise ecosystem service delivery, including fisheries' catches. In this work, we explore 1) the impact of trawling activities on benthic functional components (after the BTA approach) and 2) how trawling impact may affect the ecosystem services delivered by benthic communities. To this aim, we assessed the provision of ecosystem services by adopting the concept of Ecosystem Service Providers (ESP), i.e. ecological units that perform ecosystem functions that will ultimately deliver ecosystem services. We studied thirteen sites subjected to different levels of fishing effort in the Mediterranean. From a range of environmental variables included in the study, we found ESPs to be mainly affected by fishing effort and grain size. Our results suggested that habitat type has significant effects on the distribution of ESPs and this natural variability influences ESP response to trawling at a specific site. In order to summarize the complex relationships between human uses, ecosystem components and the demand for ecosystem services in trawling grounds, we adapted a DPSIR (Drivers–Pressures–State Change–Impact–Response) framework to the study area, emphasizing the role of society as Drivers of change and actors demanding management Responses. This integrative framework aims to inform managers about the interactions between all the elements involved in the management of trawling grounds, highlighting the need for an integrated approach in order to ensure ecosystem service provision.

Burrowing activity by armadillos in agroecosystems of central Argentina: Biogeography, land use, and rainfall effects

Land use change and agricultural practices are among the main factors affecting biodiversity, and require understanding of how differing species responses shape wildlife communities in rural landscapes. During the last 2–3 decades, the Pampas of central Argentina have experienced an agricultural expansion along with rapid adoption of a non-tillage system. In some areas armadillos are increasingly considered agricultural pests, not only because they can damage and contaminate silo bags and may act as direct consumers of crops, but also their burrowing activities interfere with farming practices. Here, we describe variations in activity of armadillos in the Pampas of Buenos Aires province, central Argentina, and discuss how biogeography, land use, and rainfall may have affected these species in the rural landscape. We carried out four sampling sessions between December 2011 and June 2013 (including two periods of normal rainfall and two periods of high rainfall), surveying 392 plots (196 crop fields and 196 rangelands) at 25 different localities (covering the five different ecological units of the Pampas). In each plot, we surveyed for signs (burrows and holes) along a 600×6m transect, in order to assess armadillo activity. Chaetophractus villosus (large hairy armadillo) showed the highest activity, with 5968 signs at 79% of the plots surveyed; whereas, 1866 signs of Dasypus hybridus (southern long-nosed armadillo) were found in 36% of the plots. Generalized linear mixed models revealed that C. villosus is more active mainly in the Inland Pampas and in cropland plots, whereas, D. hybridus is more active in the Flooding Pampas at plots with active livestock use. Both species showed less burrowing activity during the second year of surveys, in a period of exceptionally high rainfall. Our results suggest that the omnivorous C. villosus may have benefited from agriculturization and non-tillage, particularly in the Inland Pampas where sandy soils favor burrowing, whereas, the more myrmecophagous D. hybridus may be in retraction.

Investigaciones arqueológicas sobre las sociedades tardías del Valle de Guandacol (Departamento Felipe Varela, oeste de La Rioja): espacio, estilos tecnológicos cerámicos y cronología

In this paper we focus on the population dynamics of the communities that inhabited the western re-gion of La Rioja province during the Regional Developments Period, according to the results obtained from the surveys carried out in diverse ecological units from Guandacol valley, western La Rioja. Likewise, we discuss chronological periods based on absolute and relative dating. From a landscape perspective, we focus our interest on the settlement patterns and we recognizespatial and temporal dispersion of technological pottery styles identified for the area. The results lead us to look over some aspects related to the occupation of the territories and the chronological framework for the Late Period in a place that is considered as a “marginal” and “peripheral” area of the ArgentineanNorthwestlargest clustered defensive sites.

RAJONIZACE EROZNÍHO OHROŽENÍ PŮD VODOU Z TAJÍCÍHO SNĚHU NA ZÁKLADĚ ANALÝZY KLIMATOLOGICKÝCH PODKLADŮ

Melting of snow in winter and early spring often causes soil erosion. The results of erosion studies show that the runoff generated in the cold period can cause more intensive erosion than in the warm half year. By analysis of the monthly catchment of suspended sediments, it was found maximum of suspended sediments in the spring likely as effect of the spring melting of snow. Erosion caused by water from melting snow in our conditions does not reach the same intensity as the erosion caused by torrential rainfall. However, the torrential rainfall has only a local character, while the spring melting of snow usually affects larger territory. Erosive potential of water stored in snow cover can be established on the basis of the quantity of water resulting from melting snow and the speed of melting snow. Erosion caused by melting snow is given by quantity and the maximum speed of water runoff, which may be enhanced by rainfall, occurring in parallel with the snow melting. The total soil loss due to melting snow is also influenced by other factors: soil moisture, which affects the size of infiltration, soil freezing, the topography, the protective effect of vegetation, soil erodibility and implemented erosion control measures.The work analyzed erosive potential of snow cover during the cold period 1981/82 to 2007/2008 for the part of the Czech Republic, which falls within the scope of the Brno branch of the Czech Hy­dro­me­teo­ro­lo­gi­cal Institute (CHMI). For zoning of erosive potential of snow cover in the area of interest 22 climatological stations has been chosen (with regard to their equitable representation in different altitudes and different climatic conditions).The work brings erosive potential determination of water stored in snow cover. Its size corresponds to the altitude and climatic conditions represented by climatic region (according to Estimated Ecological Pedological Unit – EPEU) of investigational sites. Closeness of the relationship, expressed as a coefficient of correlation is 0.794, respectively 0.844. By the GIS interpolation on the basis of altitude a map of the erosive potential of the water stored in snow cover for the field of interest was processed.