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1
Content available remote Plant diversity along an elevation gradient in hyrcanian forest of Northern Iran
EN
Species diversity is one of the most important and fundamental issues in ecology. The present study was conducted to evaluate effects of elevation gradient on biodiversity in a temperate mountainous forest. For collection of trees' diversity data, 44 sample plots 20 × 20 m2 were set up every 50 m of the elevation interval at the altitude ranging from 100 m to 2250 m a.s.l. Also for collection of data on herbaceous vegetation, five microplots (1 × 2 m) were established (one microplot in the center and four microplots in the four corners of the plot). Species diversity values were analyzed using Simpson and modified Shannon Wiener indices. Also, species richness was calculated using Margalef and Smith-Wilson indices for each plot. The results from Simpson and modified Shannon Wiener biodiversity indices imply approximately bell-shaped diversity curves with the greatest species richness at medium elevations (800–1300 m a.s.l). However, if ecotones (gradual changes between two communities) are excluded, one can conclude that species biodiversity decreases with increasing elevation. The lowland community has the least richness that can be the result of the anthropogenic pressure. The evenness indices for the forest sites along the elevation gradient detected no trend with increasing elevation.
EN
The objective of this study was to precisely identify the types of forest resources utilization in two local communities. All forest plants used were identified and classified based on their types and classes during data collection. Semi-structural interviews through questionnaires were undertaken to obtain daily information. The results showed that there were a total of 64 forest plant life forms and categories extracted for various reasons. Most of the subject forest plants were found in the surrounding lowland tropical forest, the dominant categories were monocotyledons followed by dicotyledons, pteridophytes, and thallophytes. A strong positive correlation was determined between the frequency of species use and the benefit value that was gained (0.6453), while a strong negative correlation was observed between the value of plant’s benefit and the difficulty of access to those plants (-0.2646). Frequency of use and the future prospect of forest plant availability (-0.1405) also showed a negative correlation.
EN
Wiedemannia ljerkae Ivković et Sinclair, 2017 is recorded from Albania for the first time (Sarandë District). The updated checklist of aquatic Empididae (Clinocerinae and Hemerodromiinae) from this country is provided. The potential diversity of the Albanian fauna of dance flies is discussed based on a comparison with faunas of neighboring countries.
EN
Using multiple classification approach to examine plant traits response to grazing and fencing (as without access to grazing) is rare. Here we used multiple classification approach to examine plant diversity, productivity and species traits response to grazing and fencing over a three-year period on the eastern part of the Qing-Hai Tibetan Plateau. The results showed that most common species response to the fence was poorly noticeable. The fencing meadows compared to those under long-term free grazing are characterized by significantly higher total species richness, but species richness declined with sampling years gradually, regardless of grazing or fencing. The correlation showed that species richness was negatively associated with mean annual temperature significantly, suggesting that abiotic factors (e.g. annual temperature) could also play important roles in driving species richness in this subalpine meadow. Total aboveground biomass was not associated with mean annual temperature and rainfall. The fencing meadow demonstrated higher community aboveground biomass relative to the grazing ones, especially the abundance of legume and graminoids increased, while the proportions of sedge decreased, suggested that grazing disturbance favours the increase of reproductive success of sedge (e.g. Kobresia humilis) in this subalpine meadow. Growth form-based analyses combined with canopy height categories should be recommended to reveal general rules and mechanisms relating to grazing.
EN
This study (conducted in western Poland) was aimed at recognizing the importance of straw heaps (SH) and manure heaps (MH) located in cultivated fields for fungal diversity in farmland. Fungi (24 species and 1 sterile form) were found in 19.1% of SH (N = 89) and 60.4% of MH (N = 169). The estimated species richness (Chao2) was 29.8 ± 12.7 and 18.1 ± 2.5 (SD), respectively. Species composition of fungal communities differed significantly between SH and MH. The studied ephemeral habitats contributed markedly to fungal diversity, both locally and on the national scale. The occurrence of fungi in SH was significantly positively related to heap size, while fungal species number in MH depended most strongly on the degree of shielding, linked with proximity of woods or shelterbelts. The results show that both the reduction of SH and MH numbers in farmlands (required by the Nitrates Directive) and landscape simplification are unfavorable for fungal diversity.
EN
The model reclamation process of the studied fly ash deposits has been started in 2003 by formation of five different experimental surface layers containing fly ash and organic matter in various combinations. Then, grass mixture was sown on these surface layers. In 2015, selected properties of plant communities growing on different variants of surface layers applied in the reclamation process were assessed. It was assumed that the type of mineral and organic substrates used in the process and their quality were the main factors affecting the long term plant diversity present on different variants of restored surfaces. The aim of this analysis was the assessment of the effectiveness of ash waste reclamation (carried out on five different types of the surface layer) after 12 years since its initiation. The long term results of the reclamation process showed that the applied surface layers allowed for an effective reclamation of ashes since all variants of experimental surfaces were totally covered by dense vegetation. The predominance of plant species from ruderal and segetal habitats indicated that the soil of the experimental habitats was fertile with neutral and slightly alkaline pH, and texture of sandy loams. The experimental surface layers with a texture of sand of favourable C:N ratio, neutral or slightly alkaline did not limit the plant development. The use of organic waste markedly contributed to the floristic diversity of the spontaneously developed vegetation. Coniferous bark used in some experimental variants had a marked effect on their floristic distinctiveness due to the presence of species preferring habitats of lower pH values.
EN
The communities of benthic macroinvertebrates, living in the estuary of Oued Souss (Agadir Bay, Morocco), were studied in parallel with the changes that this ecosystem had underwent after the stopping of pollution, caused by untreated wastewater discharge which occurred in November 2002. Three campaigns were undertaken during the summer season. Two of them were carried out while the estuary was receiving wastewater discharge in 2001 and 2002. The 2003 campaign was carried out after the cessation of the pollution. The intertidal macrobenthic fauna shows a similar faunal composition for both seasons during the period when the ecosystem was receiving wastewater discharge. During this period, Hydrobia ulvae was the dominant species, followed by Hediste diversicolor and Scrobicularia plana in decreasing order. In 2003, the number of individuals harvested was significantly larger compared to the period when the ecosystem received wastewater. For the dominance of species, H. diversicolor was dominanted, followed by H. ulvae, Cerastoderma edule, and S. plana in decreasing order. However, in both periods: before and after the end of wastewater discharge, the phylum of mollusks is dominant, followed by that of Annelids and Crustaceans. The study of the coenotic affinity between settlements of different radials allowed us to separate 2–3 groups of radials in 2001 and 2002, respectively, and 3 groups after stopping discharges in the estuary. The specific richness was greater in the year following the end of discharges (22 species in 2003 instead of 14 found during the pollution period: 2001–2002). The longitudinal distribution of the species living in this site in 2001 and 2002 became wider in 2003 and average biomass, determined by the study of the ash-free dry weight, became clearly greater (20.46 g/m2 in 2003; and 15.54 g/ m2 or 15.84 g/ m2 in 2001 or 2002 respectively). This investigation allowed us to acquire a qualitative (species list, species richness) and quantitative (abundance, biomass, species density) database of intertidal benthic macrofauna of the Oued Souss estuary. It represents a reference state. It responds to the requests for information about the quality of the environment immediately after the cessation of wastewater discharge and could serve as a basis for conducting impact studies later.
EN
Edge to interior gradients in forest ecosystems can influence the species composition and community structure as a result of variations in micro-environment. In this study, the edge effects on stand productivity and plant species diversity were investigated in two adjacent types of forests in central-southern China: Chinese fir adjacent with pine forests and Chinese fir adjacent with broad-leaved forests. A total of 48 sample plots for overstory and 240 sample quadrates for understory in different stand ages were set up. The tree growth parameters were measured in the overstory while the plant species diversity was measured in both overstory and understory of the examined forests. The results showed that DBH (tree diameter at the breast height), tree height and stand volume in overstory increased from the central areas (CA) of forests to the edge areas (EA), and the plant species richness and diversity in understory were greater in EA than in CA. The edge effect was greater in Chinese fir paired with broad-leaved forests than in Chinese fir paired with pine forests. The edge effect decreased in an order as young aged stands > middle aged stands > mature aged stands in the studied forests. The changes in tree growth and species diversity in the edge area compared to the interior were mainly attributed to the alteration of micro-environmental factors such as light density, temperature and moisture. Our results suggest increasing forest productivity and plant species diversity could be achieved by making more edges in the forests.
EN
Coastal Lake Bardawil (Egypt) is one of the largest hypersaline lakes in the world. In 2009-2010, the authors studied composition, distribution and seasonal dynamics of copepods at 12 sites. A total of 10 species of copepods were recorded in zooplankton during the study period, including 5 Calanoida, 2 Cyclopoida and 3 Harpacticoida. Oithona nana was the most common and most abundant species. All copepods in the lake can be divided into three groups: 1) planktic species that form stable populations, 2) species of Mediterranean plankton incidentally entering the lake from the adjacent sea area, 3) benthic Cyclopoida and Harpacticoida that can be abundant in plankton. Two species - Acartia tonsa and A. danae were recorded here for the first time. The total abundance of copepods in the lake was significantly higher (90 times on average) compared to that observed in 2008-2009 in the waters of the Egyptian Mediterranean Sea. Since 1967, the complex of common and dominant copepod species in the lake has changed significantly. The total average annual copepod abundance varied: in 2002 - it was about 4000 ind. m-3, in 2004 - 152 000 ind. m-3, in 2005 - about 25 300 ind. m-3, and in 2009-2010 - about 56 000 ind. m-3.
EN
Artificial grassland establishment is one of the fastest and most effective ways to restore the productivity of degraded grasslands. Little is known about the effect of different types of artificial grassland establishment (i.e., single- and mixed-sowing grassland establishment with perennial grasses) on soil seed bank in degraded grassland ecosystems. Single-sowing population of a high yield species usually has a great standing biomass causing shading that may inhibit germination of seeds in soil seed bank. Thus, we hypothesized that there is higher species richness and seed density in the soil seed bank of single-sowing than mixed-sowing grasslands. Here, we investigated the soil seed bank in four-year old single-sowing and mixed-sowing and control (degraded) grasslands on the Qinghai-Tibetan Plateau. We found that the autumn seed bank of mixed-sowing grasslands had lower species richness and seed density than single-sowing grasslands, while the summer soil seed bank (persistent seed bank) showed little differences. There were differences in biomass among the three grasslands (single-sowing > mixed-sowing > control), but there was no differences in species richness of vegetation. In sum, our results of the autumn seed bank support our hypothesis. Greater above-ground biomass in single-sowing grasslands could generally cause low light availability preventing seeds in soil from germinating and support more seed output, which both may indirectly or directly result in the relatively higher species richness and seed density in the soil seed bank. Our results also suggest that artificial grasslands usually returning to native grasslands in terms of production and species composition after several years is likely due to stability of the persistent soil seed bank.
EN
The generalization and analysis of original data have shown that the nature of epiphytic algae distribution on higher aquatic plants, representing different ecological groups, is very similar in various types of numerous water bodies in the Dnieper River basin. Their species richness and values of quantitative indices were mostly higher on submerged plants compared to plants of other ecological groups. The number of epiphytic algae species was 1.1-1.7 times higher on submerged plants compared to that on half-submerged plants and 1.6-3.1 times higher compared to plants with floating leaves. The taxonomic structure and species composition of epiphyton were very similar on half-submerged and submerged plants and moderately similar on plants with floating leaves compared to macrophytes of other ecological groups. It is emphasized that the specificity of epiphytic algae distribution on macrophytes of various ecological groups should be taken into account when performing monitoring and assessment of the ecological status of water bodies by the bioindication method.
EN
The objective of this study was to examine the vegetation cover and describe the floristic diversity of selected plant communities of extensive and abandoned grasslands within the Forest of Parczew PLB060006 – a Natura 2000 protected area. Floristic surveys were conducted in the meadows in years 2001 and 2013 under the conditions of natural succession of the communities Poa pratensis-Festuca rubra. The area is situated in the northern part of the Lublin Voivodeship, in the physiographic mesoregion the Łęczna-Włodawa Lakeland. Those communities were characterized by average species richness and floristic diversity index values. The cover index decreased considerably in the case of 8 species, and increased for 12 species. A large increase in the cover index of Holcus lanatus, Deschampsia caespitosa, Galium mollugo, Anthriscus sylvestris and Polemonium caeruleae is particularly noteworthy. In 2001, 39 species of plants were recorded in all relevés, compared to 41 species recorded in 2013. Over 12 years, 11 species disappeared, but 13 new ones emerged. For the time being, the average species richness N increased from 12 to 16 per relevé. The biodiversity index H' increased from 2.8 to 3.6.
PL
W artykule przedstawiono wyniki badań fitosocjologicznych na obiekcie Ochoża prowadzonych w 2001 i 2013 r. Z analizy danych wynika, że gatunkami występującymi na wszystkich badanych stanowiskach były głównie Poa pratensis i Festuca rubra oraz Urtica dioica. W 2013 r. na wszystkich badanych stanowiskach, oprócz gatunków omówionych wyżej, występowały także Rumex acetosa, Galium mollugo, Veronica chamaedrys i Cardaminopsis arenosa. Na podstawie analizy wyników badań stwierdzono, że w przypadku 15 gatunków klasa stałości w 2013 r. w porównaniu ze stanem z 2001 r. zwiększyła się, a w przypadku pozostałych się nie zmieniła. Odnotowano także zmiany współczynnika pokrycia. Uległ on znacznemu zmniejszeniu w przypadku 8 gatunków, a zwiększył się w przypadku 12 gatunków. Na szczególną uwagę zasługuje duże zwiększenie wartości współczynnika pokrycia Holcus lanatus, Deschampsia caespitosa, Galium mollugo, Anthriscus sylvestris oraz Polemonium caeruleae (w Polsce gatunek objęty ochroną prawną). W 2001 r. we wszystkich stanowiskach odnotowano 39 gatunków roślin, zaś w 2013 r. odnotowano 41 gatunków. Przez 12 lat zanikło 11 gatunków, ale pojawiło się 13 nowych. Przez 12 lat średnia liczba gatunków N zwiększyła się z 12 do 16. Zwiększył się także wskaźnik bioróżnorodności H’ z 2,8 do 3,6.
EN
Grasslands were seen in the past primarily as a source of feed. The important function of grassland, beside the role of feed, consists in their natural value and role in the landscape. The aim of this study was to assess natural and landscape values of the distinguished meadow-pasture communities in Kłodzko. It is located in the south-western part of Poland, within the Sudety chain and is surrounded by mountains that form its natural boundary. The whole area of the county is very diverse in terms of physiogeography and climate what affects its natural and landscape values. The natural value of the seven distinguished plant units: 4 assosciations - Angelico-Cirsietum oleracei, Arrhenatheretum elatioris, Lolio-Cynosuretum, FestucoCynosuretum, 3 communities with dominant species - Poa pratensis-Festuca rubra, community with Agrostis capillarisFestuca rubra, community with Trisetum flavescens, on subject area was determined on the basis of the species richness represented by the total number of species, the Shannon-Wiener species diversity index H' and the presence of endangered and rare species. These phytocenoses are characterized by a large species richness from 34 to 150 species. The values of the H' index are at an average level and ranged from 2.32 to 2.64. Community with Trisetum flavescens is characterized by the highest diversity index value. The biggest species richness is in the Lolio-Cynosuretum. Among species legally protected are noted in Poland: Carlina acaulis and Colchicum autumnale and near threatened (NT) Geranium sylvaticum. Plant species richness, the high proportion of the color of flowering herbs and weeds and Fabaceae plants flowering in different time of the growing season, affect the aesthetic qualities and the landscape values of the meadow-pasture communities analyzed. Their location in the landscape varied with hills and terrain, enhancing the landscapes of the studied Kłodzko county.
PL
Użytki zielone postrzegane były w przeszłości przede wszystkim jako źródło paszy. Obecnie, zwłaszcza w sytuacji zaniechania lub ograniczania chowu zwierząt, ważną funkcją użytków zielonych, obok roli paszowej, jest ich wartość przyrodnicza i rola w krajobrazie. Celem pracy było określenie wartości przyrodniczej oraz krajobrazowej wyróżnionych zbiorowisk łąkowo-pastwiskowych w powiecie kłodzkim, który znajduje się w południowo-zachodniej części Polski, w obrębie łańcucha Sudetów. Otoczony jest górami stanowiącymi jego naturalną granicę. Cały obszar powiatu jest silnie zróżnicowany pod względem fizjogeograficznym i klimatycznym, co wpływa na jego walory przyrodnicze i krajobrazowe. Walory przyrodnicze wyróżnionych na badanym terenie siedmiu zbiorowisk roślinnych (4 zespołów - Angelico-Cirsietum oleracei, Arrhenatheretum elatioris, Lolio-Cynosuretum, Festuco-Cynosuretum oraz 3 zbiorowisk z gatunkiem dominującym: Poa pratensisFestuca rubra, zbiorowisko z Agrostis capillaris-Festuca rubra, zbiorowisko z Trisetum flavescens) określono na podstawie bogactwa gatunkowego wyrażonego liczbą gatunków ogółem, współczynnika różnorodności gatunkowej ShannonaWienera, wyrażonego wskaźnikiem H' oraz obecności gatunków chronionych i rzadkich. Fitocenozy te charakteryzują się dużym bogactwem gatunkowym od 34 do 150 gatunków. Wartości wskaźnika H’ kształtują się na średnim poziomie i wynoszą od 2,32 do 2,64. Najwyższą wartością współczynnika różnorodności charakteryzuje się zbiorowisko z Trisetum flavescens, a największym bogactwem gatunkowym Lolio-Cynosuretum. Spośród gatunków prawnie chronionych w Polsce odnotowano obecność: Carlina acaulis i Colchicum autumnale, a bliskich zagrożenia (NT) - gatunek Geranium sylvaticum. Bogactwo gatunkowe roślin, wysoki udział barwnie kwitnących w różnych porach sezonu wegetacyjnego ziół i chwastów oraz roślin z rodziny bobowatych wpływają na walory estetyczne i krajobrazowe analizowanych zbiorowisk łąkowo-pastwiskowych. Ich lokalizacja w krajobrazie urozmaiconym wzniesieniami, zagłębieniami terenu, podnoszą atrakcyjność badanych rejonów powiatu kłodzkiego.
EN
Seed plant diversity is under threat due to human over-exploitation and changes in land use. There is a need to identify regions where seed plant diversity is most at risk and establish nature reserves to protect the most important species. This study collected province scale seed plant richness data and corresponding environmental, social and, economic data in China in order to assess the impact of environmental and socio-economic factors on seed plant diversity and to quantify the relative importance of climate, human disturbance, and habitat heterogeneity on the distribution of seed plant diversity. A downscaling model was established to map the spatial distribution of seed plant diversity at a 1-km resolution. The results showed that temperature and precipitation seasonality, potential evapotranspiration, humidity index, altitude range, and gross domestic product were important determinants of seed plant diversity. The relative contribution of temperature seasonality was the most important factor (explaining 29.9–36.2% of the variation). Climate, human disturbance, and habitat heterogeneity explained much of the seed plant richness and density variation (about 69.4–71.9%). A scale-down model explained 72% of seed plant richness variation and showed that the center of seed plant species diversity was mainly located in the southeast area of China in the Qing-Tibet Plateau, Yun-Gui Plateau, Hengduan Mountain region, middle of the Sichuan Basins, Taiwan island, and Hainan island. This study improves our understanding of biodiversity hotspot regions and is a useful tool for biodiversity conservation policy and nature reserve management in China.
PL
W prawie bezleśnym krajobrazie rolniczym Płaskowyżu Proszowickiego łąki stanowią jego ważny i cenny element. Dominują w szerokich dolinach Szreniawy i Nidzicy, porastają podnóża i zbocza neolitycznych kurhanów oraz średniowiecznego grodziska w Stradowie. Obecne są też w dolinie Wisły. Rozległy, zajmujący 770 km2 Płaskowyż Proszowicki, będący subregionem Niecki Nidziańskiej, ze względu na sprzyjające warunki przyrodnicze oraz intensywne użytkowanie od neolitu, jest typowym obszarem rolniczym. W latach 1997-2000 w tym słabo poznanym fitosocjologicznie terenie, przeprowadzono badania szaty roślinnej, które potem były kontynuowane. W artykule przedstawiono wyniki badań przeprowadzonych w zbiorowiskach łąkowych i szuwarowych. Stosując metodę Braun-Blanqueta wykonano 1600 zdjęć fitosocjologicznych. Uzyskane dane przeanalizowano metodami numerycznymi i statystycznymi. Stwierdzono, że występowanie muraw kserotermicznych (Festuco-Brometea) i łąk wilgotnych (zwłaszcza ze związku Calthion) jest charakterystycznym rysem szaty roślinnej Płaskowyżu Proszowickiego. W zbiorowiskach tych rosną gatunki rzadko występujące w innych regionach kraju a ich rozmieszczenie przestrzenne, związane z rozmaitymi formami terenu i zróżnicowanym podłożem, wpływa znacznie na heterogeniczność krajobrazu, w którym aż 80% terenu pokrywają pola uprawne. W grupie łąk kośnych i szuwarów wyróżniono 32 zespoły i 4 zbiorowiska roślinne. Na podstawie analizy zdjęć fitosocjologicznych z fitocenoz 5 głównych zespołów stwierdzono istotne statystycznie zależności między liczbą gatunków a wilgotnością gleby, nachyleniem zboczy, użytkowaniem i typem łąki. Najbogatsze w gatunki okazały się fitocenozy rosnące na lekko nachylonych zboczach, na glebach świeżych. Szczególnie wyraźnie zaznaczył się wpływ użytkowania na bogactwo gatunkowe płatów użytkowanych w porównaniu z płatami porzuconymi.
EN
In strongly deforested landscape of the Proszowice Plateau, in 80% covered by arable lands, meadows form an important and valuable element. They dominate in extended valleys of the Szreniawa and Nidzica rivers, where occupied bottoms and slopes of the Neolithic tomb mounds (barrows), and wide area of the Medieval settlement in Stradów. They are also present in the Vistula River valley. Due to the favourable natural conditions and intensive land management since the Neolithic, the vast 770-km2 area of the Proszowice Plateau, i.e. a subregion of the Nida Basin, is a typical agricultural area. In 1997-2000, investigations of the vegetation cover were carried out and later continued in this region, which is still poorly explored in terms of phytosociology. This article presents results of research conducted in meadow and swamp communities. 1600 phytosociological releves were taken with the use of the Braun-Blanquet method the data obtained were analysed with multivariate and statistical methods. It was found that the occurrence of xerothermic grasslands (Festuco-Brometea) and wet meadows (particularly from the alliance Calthion) is a characteristic feature of the vegetation cover in the Proszowice Plateau. These communities comprise species that are rare in other regions of the country, and their spatial distribution associated with various terrain forms and diverse substrates exerts a substantial effect on the heterogeneity of the landscape. In the groups of meadows and rushes, 32 associations and 4 plant communities were distinguished. Based on the phytosociological releves from the phytocoenoses of five main associations, statistically significant relationships were found between the number of species and soil moisture, slope inclination, and the meadow management and type. Phytocoenoses growing on slightly inclined slopes and fresh soils exhibited the highest species richness. Particularly evident was the influence of the type of land management on the species richness in managed patches, compared with the abandoned land.
EN
Habitat edges are regarded as important components of heterogeneous landscapes. Diverse theories exist about the diversity and functional role of edges, and no generalisation have been possible so far, thus case studies are important for better understanding the landscape scale processes. Forest management highly modified the structure and tree species composition of the European forests. The sylvicultural intensification resulted in the rise of the proportion of non-native, intensively managed forest stands. In the present study we explore the response of spider and ant assemblages to forest stand type and the edge effect between native poplar and non-native conifer plantations in Hungary. We applied pitfall traps to sample the ground-dwelling spiders and ants. Four plots consisting of the two forest types and the transition zones between them were selected. Five transects for each replicated plot were sampled. We identified the significant indicator species of the different habitat types. We found significant differences in the species richness (i.e. number of species) of ants and spiders of the different habitat types. We detected intermediate spider species richness at the edge indicating that edges separate a higher quality habitat from one that has lower resource quality; however, the species richness of ants was the highest at the edge and did not differ between the two forest types. The positive impacts of edge was found due to presence of generalist and grassland species at the edge and presumably edges separate patches that provide complementary resources also increasing the number of ant species. Our results indicate that forest type affects the species compositions of ground-dwelling spiders and ants. Our study also shows that habitat type had a major effect on the species richness and composition of spider and ant assemblages, suggesting that local forestry management plays a crucial role in preserving the native invertebrate fauna of forests.
17
Content available remote Towards a general species-time-area-sampling effort relationship
EN
Species – area (SAR) and species time (STR) relationships describe the increase of species richness with study area and study time and have received much attention among ecologists and are used in different branches of biodiversity research. Unknown sample size effects often hinder a direct comparison of SAR and STR shapes of different taxa and regions. Further, space and time interact during the accumulation of species due to the common sample universe. Here we develop a simple power function scaling model of species richness that integrates space, time, sample size and their interactions. We show that this model is able to precisely describe average species densities and the increase of species richness in a regional metacommunity of a large sample of spiders on Mazurian lake islands (Northern Poland). The model predicts strong area – sample size and time – sample size interactions. Judged from the SAR (z = 0.08) and STR (y = 0.64) slopes it points to only moderate spatial β–diversities but high local temporal species turnover. We suspect that the parameters of many published SARs are strongly influenced by unknown sampling time and sample size effects that make direct comparison difficult.
EN
The positive relationship between the number of species in an area and the size of the habitat studied (species-area relationship, SAR) is the foundation of ecological theory and the most studied issues in ecology. However, very few studies have addressed SARs and their relationships to functional group richness and the extent of habitat area studied. We analyzed SARs in different functional groups focusing on two types of tropical monsoon rainforests on Hainan Island, China. The number of trees, shrubs, lianas, all species, deciduous species, evergreen species, thorn species, non-thorn species, simple-leaved species, and compound-leaved species were strongly related to the size of the area studied in the two tropical monsoon rainforest communities. And the size of the area studied explained over 94% of the total variations in the number of families and other groups studied. No significant differences were found for the slope of the species-area curve (Z) of different functional groups in two tropical monsoon rainforest communities except for shrubs that were taller in the Terminalia hainanensis community (TC) than in Liquidambar formosana community (LC). In the comparison of different functional groups divided by the same principle in the same tropical monsoon rainforest, no significant difference was found for the value of Z for different functional groups except that Z for lianas were higher than for shrubs in LC. However, the Z of lianas was higher than that of trees and shrubs, and evergreen species and species without thorns had higher Z values than deciduous species and species with thorns. No significant differences were found between simple-leaved species and compound-leaved species in TC. The results indicated the SARs of different plant functional groups can be well-described by the power function, although their slopes differed significantly.
EN
The loss of biodiversity caused by wetland degradation is a hot issue in ecology. It is known that hydrological degradation is the primary reason resulting in wetland degradation, but little is known about the relationship between plant species richness and environmental factors in different wetland types along a hydrological gradient. According to the gradient from high to low water level, wetland remnants in the Sanjiang Plain of northeast China were classified into three wetland types, which were permanently inundated marshes (PIM), seasonally inundated marshes (SIM) and wet meadows (WM) respectively. In this paper, we aimed to identify the determinants of plant species richness in the three wetland types and discern the transition of the determinants along a hydrological gradient. Plant species richness as well as area, habitat heterogeneity and resource availability was investigated in 51 wetland remnants, which were composed of 6 PIM, 25 SIM and 20 WM. Averagely, the area of wetland remnants occupied by PIM, SIM and WM was 0.35 ± 0.17 ha, 2.81 ± 2.88 ha and 1.34 ± 1.18 ha respectively. Aggregating the species in each wetland type, there were 67, 244 and 170 species recorded in PIM, SIM and WM. The determinants of species richness varied in different wetland types: standing water depth in PIM, area and water heterogeneity in SIM, and soil fertility and area in WM. With the decreasing water level, the influence of hydrological condition on species richness in the three wetland types declined while the impact of area and soil fertility gradually increased. Thus, hydrological condition was probably responsible for the transition of the determinants of species richness in different wetland types. Moreover, the habitat specialists of wetland would be lost when PIM or SIM degraded to WM. In order to conserve and restore plant diversity, specific measures should be taken including preventing area loss for all wetland remnants, managing the hydrological process for PIM and SIM, and regulating soil nutrient for WM.
EN
The composition and distribution of ground beetles species in the different urban green areas of the Lublin city, Eastern Poland was studied. Carabids were collected since the end of April till the late July 2011 using pitfall traps. In total 67 carabid species were found during of the study period. The number of species varies from 54 in valley of Bystrzyca to 5 on the lawns along street. The highest species richness (5.94) had the studied floodplain of river Bystrzyca in comparison with other green territories. All studied green areas were distinguished by considerable individuality. Our results support the thesis that despite of the sizeable areas of the lawns and flowerbeds, their role in the diversity maintenance and preservation is minimal.
PL
W pracy omówiono wyniki badań dotyczących składu gatunkowego zgrupowania biegaczowatych na różnych obszarach zieleni miejskiej w Lublinie (Polska). Badania prowadzone były od końca kwietnia do końca lipca 2011 roku; odłowy biegaczowatych prowadzono za pomocą pułapek naziemnych. W czasie przeprowadzonych badań odłowiono łącznie 67 gatunków biegaczowatych. Liczba gatunków stwierdzonych podczas badań kolejnych obszarów wahała się od 54 do 5. Największą wartością wskaźnika bogactwa gatunkowego Margalefa (5.94) charakteryzował się teras zalewowy rzeki Bystrzycy w porównaniu do innych obszarów zieleni miejskiej. Na podstawie składu gatunkowego poszczególnych stanowisk można stwierdzić znaczne różnice między nimi. Wyniki wskazują również, że pomimo znaczących obszarów trawników na terenie miasta Lublin ich rola w utrzymaniu i ochronie różnorodności biegaczowatych jest minimalna.
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