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Breeding Biology of Booted Eagle Hieraaetus Pennatus (Gmelin, Jf, 1788): The First Study in North Africa

Abstract

Knowledge and study of breeding birds’ biology is essential to understand the dynamic, assess productivity and identify threats. The population of booted eagles (Hieraaetus pennatus) was studied during three consecutive breeding seasons (2013−2015) in the Chettabah forest. Each year, arrivals of Booted eagles are recorded during March (15 individuals in 2013, 12 in 2014 and 11 in 2015). For the three years of study, the mean breeding pair’s density was 1.23 ± 0.153/km2, incubation period ranged from 33 to 38 days, whilst the frequency distribution of clutch size was 67.6% for 2 eggs, 27% for 1 and 5.4% for 3. Amongst the 63 eggs monitored, 55 hatched. No significant variation in hatching rate was observed during the 3 years (90% in 2013, 76.19% in 2014 and 84% in 2015). The comparison of breeding parameters with those reported in Spain showed a noticeable similarity. Further investigations should be conducted to improve the provision of information to support sound management interventions of this North African population.

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Changes in Snowbed Vegetation in the Western Carpathians Under Changing Climatic Conditions and Land Use in the Last Decades

Abstract

Snowbed vegetation is one of the most sensitive alpine vegetation type to the climate change, because shortened period of snow cover has essential impact on the snowbed environment. We focus on its changes in the Western Tatras, which is a part of the Western Carpathians (Slovakia). The assessment of changes in snowbed vegetation is based on the method of pair comparison. In 2016–2018, we resampled 21 historical phytocoenological relevés of Festucion picturatae and Salicion herbaceae alliances from 1974 and 1976. Historical data include 45 species, while recent data include 50 species. We observed a decrease in the frequency of species characteristic for snowbeds and, on the other hand, an increase in that for strong competitors, especially grasses and small shrubs from adjacent habitats. According to Ellenberg’s ecological indices, there is some increase in temperature and decrease in light ecological factors in snowbed habitats. In S. herbaceae data, a statistically significant increase in the average species number was observed with new species that penetrated from the adjacent habitats. Changes in species composition between historical and recent data are confirmed by Non-metric multidimensional scaling (nMDS) ordination diagram. Linear mixed-effect models showed big variability in factors that have impact on phytodiversity; nevertheless, temperature is the most significant factor.

Open access
Fitting Competing Models of the Population Abundance Distribution: Land Snails from Nikopol Manganese Ore Basin Technosols

Abstract

This paper examines the temporal dynamics of terrestrial mollusks of the Nikopol manganese ore basin technosols. The research was carried out at the Research Centre of the Dnipro Agrarian and Economic University in Pokrov (Ukraine). Sampling was carried out in 2012–2014 on four variants of artificial soil: formed on red-brown clays, on loess-like loams, on gray-green clays, and on humus-rich layer. The distribution of the number of individuals in a mollusk population was described by broken stick, Motomura, log-normal, Zipf, and Zipf-Mandelbrot models. It was shown that the series of models that best describe mollusk abundance distribution is specific for a particular species and technosols type and generally is invariant over time.

Open access
Floristic Distribution According to the Edaphic Parameters of a Steppe Zone, Case of Study: The Nature Reserve “El-Mergueb” M’sila, Algeria

Abstract

The natural site of El-Mergueb, is one of the specific steppe ecosystem, that occupies an area of 16,481 ha; it is among the particular ecosystems in Algeria and is unique in northern Africa. It is located in the geographical limit of the Tell Atlas and the Saharan Atlas. It is at an altitude of 550 to 800 m, with a typically arid climate. The faunistic and floristic richness, quite specifically, contains species protected and classified in the IUCN: Chlamydotis and Gazella, as well as an autochthonous plant diversity: Stipa, Pistacia and Ziziphus. This study is based on the analysis of the vegetation by characterizing the associated soil type through the monitoring of the Eco-pedological relation during two seasons in three years: 2015−2016−2017. Nine soil profiles with a collection of twenty-one samples for each station of experimentation were collected. The results thus obtained showed that the content of the parameters analyzed is between low and average of the three stations. The average of the floristic analysis of the study area made it possible to define 34 botanical families spread over 69 botanical genus and 275 species. The analysis and the description of a natural space is important to establish a typology which is that is the basis for the development of management plans to conserve this category of protected areas. The FAC (Factorial Analysis of Correspondence) is relative to the individualization and the typology for three sequences, which corresponds to the groups (A), (B) and (C) also for the places in arid climate variants with very cold winters.

Open access
Landsliding as a Limit to Possible Territorial Development in the Kysuce Region

Abstract

The growing development of settlements in mountainous areas and their sustainable development constantly requires new approaches to assess the land in terms of occurrence of landslides. The flysch zone, where the monitored area is located, is one of the most landslide prone areas in Slovakia. Landslides respond sensitively to the quality of the individual factors that form the landscape and to the change of natural conditions. Their occurrence is a geo-barrier that reduces or totally prevents the use of natural environment and negatively affects the life of population and territorial development. The reason for the increased hazard of landslides is not only demographic pressure on territories, but also its poor management. Consistent spatial planning addresses not only the spatial layout but also the functional use of the territory. Landslides represent one of the limits of land use. This study is based on the assessment of landsliding as a limit to possible territorial development. The input parameters for the assessment were elements of the current landscape structure (built up structure, forest stands, transitional woodland-shrubs, traditional agricultural land, permanent grasslands and arable land) and occurring landslides (active, potential and stabilized). On most of the determined elements of the landscape, landslides occur on about a quarter of their area. They have a smaller share only in areas of mixed forests, built up areas and have the smallest share on arable land. Potential landslides have the largest proportion on all landscape elements. They occupy the largest areas on coniferous forests (1578.93 ha) and on permanent grasslands (741.33 ha). By evaluating the overall endangerment of the area by landslides according to the degree of threat, we found that the greatest threat of landslides is in the Skalité and Svrčinovec cadastral areas, the smallest threat is in the Čadca cadastral area. In addition to the danger of landsliding in the individual elements of the landscape, we have also set limits for its development. Spatial planning limits have been divided into two categories according to the sectors they affect the most: limiting the development of an area assigned for residential building, or restricting the development of an area designed for agricultural and forestry purposes.

Open access
Model of the Representative Geoecosystem at Regional Level

Abstract

The paper is aimed at the presentation of the new conception of nature protection. The new conception is based on the creation and protection of the representative geoecosystems. The strategic aim of defining the representative geo-ecosystem is: to determine a representative geo-ecosystem for each territorial unit on the given hierarchical level - the regional principle, to determine a representative occurrence for each type of the geo-ecosystem – the typological principle. The list of types of representative geo-ecosystems should serve as an ecologically based systematic framework for new protected areas (according to the analysis of unsufficiently protected representative geo-ecosystems) designations, as well as for methodical proposals of biocentres of the territorial system of ecological stability. The new approach to nature conservation is based not only on the protection of life forms but also on the protection of living conditions.

The paper presents an example of the creation of representative geoecosystems on the regional level–Trnava region.

Open access
Simulation of Decline of Norway Spruce (Picea Abies L. Karst.) Forests in Gorgan Mountains (Ukrainian Carpathians): Case Study Using Forkome Model

Abstract

The FORKOME model used in the article contains elements of forest and ecological approaches and was specially developed for the conditions of the Gorgans. The modeling was performed based on the single simulation results and statistically averaged forecast of 200 simulations (“Monte Carlo”) in order to show the tendency of changes and their correspondence with single simulations. The forecast of the forest dynamics was conducted at the 100th anniversary period with “control” and “warm-dry” scenarios. It has been revealed that the rapid decrease in biomass in the first decade was caused by Norway spruce decline. It was revealed that in the control scenario, the most active biomass growth during the 100th year forecast was shown by Silver fir (Abies alba Mill.) and beech (Fagus sylvatica L.). The fir reacted relatively sensitively to the warming and decrease in rainfall. The relationships between tree species and the influence of biomass of Norway spruce tree on the biomass of the whole forest tree stand were analyzed.

Open access
The effect of soil on spatial variation of the herbaceous layer modulated by overstorey in an Eastern European poplar-willow forest

Abstract

The tree species composition can influence the dynamics of herbaceous species and enhance the spatial heterogeneity of the soil. But there is very little evidence on how both overstorey structure and soil properties affect the spatial variation of the herb layer. The aim of this study is to evaluate the factors of the soil and overstorey structure by which it is possible to explain the fine-scale variation of herbaceous layer communities in an Eastern European poplar-willow forest. The research was conducted in the “Dnipro-Orils’kiy” Nature Reserve (Ukraine). The research polygon (48°30′51″N, 34°49″02″E) was laid in an Eastern European poplar-willow forest in the floodplain of the River Protich, which is a left inflow of the River Dnipro. The site consists of 7 transects. Each transect was made up of 15 test points. The distance between rows in the site was 3 m. At the site, we established a plot of 45×21 m, with 105 subplots of 3×3 m organized in a regular grid. The adjacent subplots were in close proximity. Vascular plant species lists were recorded at each 3×3 m subplot along with visual estimates of species cover using the nine-degree Braun-Blanquet scale. Within the plot, all woody stems ≥ 1 cm in diameter at breast height were measured and mapped. Dixon’s segregation index was calculated for tree species to quantify their relative spatial mixing. Based on geobotanical descriptions, a phytoindicative assessment of environmental factors according to the Didukh scale was made. The redundancy analysis was used for the analysis of variance in the herbaceous layer species composition. The geographic coordinates of sampling locations were used to generate a set of orthogonal eigenvector-based spatial variables. Two measurements of the overstorey spatial structure were applied: the distances from the nearest tree of each species and the distance based on the evaluation of spatial density of point objects, which are separate trees. In both cases, the distance matrix of sampling locations was calculated, which provided the opportunity to generate eigenvector-based spatial variables. A kernel smoothed intensity function was used to compute the density of the trees’ spatial distribution from the point patterns’ data. Gaussian kernel functions with various bandwidths were used. The coordinates of sampling locations in the space obtained after the conversion of the trees’ spatial distribution densities were used to generate a set of orthogonal eigenvector-based spatial variables, each of them representing a pattern of particular scale within the extent of the bandwidth area structured according to distance and reciprocal placement of the trees. An overall test of random labelling reveals the total nonrandom distribution of the tree stems within the site. The unexplained variation consists of 43.8%. The variation explained solely by soil variables is equal to 15.5%, while the variation explained both by spatial and soil variables is 18.0%. The measure of the overstorey spatial structure, which is based on the evaluation of its density enables us to obtain different estimations depending on the bandwidth. The bandwidth affects the explanatory capacity of the tree stand. A considerable part of the plant community variation explained by soil factors was spatially structured. The orthogonal eigenvector-based spatial variables (dbMEMs) approach can be extended to quantifying the effect of forest structures on the herbaceous layer community. The measure of the overstorey spatial structure, which is based on the evaluation of its density, was very useful in explaining herbaceous layer community variation.

Open access
The effect of the selected remediation medium on the cadmium bioavailability in the selected ecosystem in the Southwestern locality of Slovakia

Abstract

Soil is a sensitive ecological factor. Biodegradable materials from the environment can also be used to deal with serious ecological problems. Soil affecting by remediation medium - garden compost - was analysed for toxic cadmium (Cd) in terms of environmental protection. The objective of this research was to analyse soil and compost at foothill locality of the Tribeč Mountains (Southwestern Slovakia) in the years 2015−2017 to determine Cd contents in soil and compost, pH and to assess Cd bioavailability. The analyses were carried out using the Atomic Absorption Spectrometry with seven-step Selective Sequential Extraction methods. The results obtained were evaluated statistically using the SAS 9.4 software method by Spearman’s correlation coefficient. The results showed that Cd contents in soil had reached 2.96 mg kg−1 and soil with compost (the ratio 1:1) 2.71 mg kg−1 dry matter. Cd contents in the soil exceeded maximum allowed limit of 196%. And deceased by 25% after adding compost. The pH in soil with compost varied from 6.78 to 7.98. The pH prevented the mobility of Cd about 8.3% in average. Statistical dependence was high, which was demonstrated for relationship between Cd in soil, pH and compost. Available Cd forms in soil were 53.3% and soil with compost were 45% in average. The garden compost as a remediation medium reduced Cd bioavailability.

Open access
Macrophytes in the littoral of Lake Arakhley in different states of water regime

Abstract

The study of aquatic vegetation in the littoral of the dimictic water bodies of taiga is of particular interest in case of long-term observations carried out under conditions of climate fluctuations. During the low-water period, drying of the littoral with a decrease in the water level leads to the changes in phytomass of macrophytes, as well as in the composition of species and their distribution by depth. The area of littoral covered with ice in winter is also large in the low-water period; it affects the growth of perennial plants. When the water level decreases, the sand beach replaces the sand and pebble beach; it leads to the disappearance of epilithon and the predominance of rooting plants. The features of vegetation were determined for each period of water content. The low-water period is characterised mostly by grass-type vegetation; the high-water period is characterised by vegetation of mixed type.

Open access