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EN
We apply the phase field crystal method for nonequilibrium patterning to stochastic systems with an external source in which transient dynamics is essential. Considering a prototype model for a one-component periodic system subjected to external influence kind of irradiation we study properties of pattern selection processes and external noise induced pattern-forming transitions. These processes are examined by means of the structure function dynamics analysis. Nonequilibrium pattern-forming transitions are analyzed numerically.
EN
In this paper, a comprehensive research of the evolution of the hierarchical structure and spatial pattern of coastal cities in China was conducted based on the data of distribution of the headquarters and subsidiaries of marine-related enterprises in 1995, 2005 and 2015 using the city network research method proposed by Taylor. The results of the empirical research showed: China’s coastal city network had an obvious hierarchical characteristics of “national coastal cityregional coastal city-sub-regional coastal city-local coastal city”, in the 20 years of development process, the hierarchies of coastal cities in China showed a hierarchical progressive evolution; in past 20 years, the spatial pattern and network structure of coastal cities in China tended to be complete, and the city network was more uniform, forming a “three tiers and three urban agglomerations” network structure; the strength of connection among the cities was obviously strengthened, and the efficiency of urban spatial connection was improved overall.
EN
Political, financial and legislative support of one’s own constituency or home location belongs to the main interests of politicians. The paper attempts to identify a spatial pattern in pork barrel grants allocated during the endorsement of draft state budgets by the Chamber of Deputies. The factor of deputies’ home locations is analysed. Correlation analysis at district level exploits Parliamentary Gazette data on approved deputies’ amendments to the draft state budget and a list of deputies’ home municipalities from electoral database of the Czech Statistical Office. At municipal level, a local indicator of spatial autocorrelation was employed to discover several spatial clusters of high and low pork barrel support, which was compared with deputies’ home locations. Although several pork barrel grants were allocated to these locations, no general correlation was confirmed.
CS
Mezi hlavní zájmy politiků patří politická, finanční i legislativní podpora svých volebních obvodů či bydlišť. Článek se pokouší odhalit pravidelnosti v prostorovém vzorci poslaneckých dotací, o kterých poslanci rozhodovali během projednávání návrhu státního rozpočtu v Poslanecké sněmovně (porcování medvěda), na základě analýzy významu lokalizace poslaneckých trvalých bydlišť pro jejich alokaci. Na úrovni okresů byla provedena analýza korelace dat přijatých pozměňovacích návrhů poslanců k návrhu státního rozpočtu ze sněmovních tisků a lokalizace poslaneckých trvalých bydlišť z volební databáze Českého statistického úřadu. Na úrovni obcí byly metodou lokálního indikátoru prostorové asociace LISA odhaleny prostorové shluky vysoké a nízké podpory poslaneckými dotacemi, které byly následně na půdorysu obvodů obcí s rozšířenou působností porovnány s trvalými bydlišti poslanců. Jejich rozmístění v několika případech odpovídalo příjmu poslaneckých dotací, obecná závislost se však nepotvrdila.
EN
This study is a review of selected issues in mathematical and statistical modeling of spatial structures and processes. The review includes a discussion of basic concepts such as spatial pattern, spatial structure and spatial process and their relationships. Then, a general (stochastic) spatial process and its components are defined with a special focus on the problem of the spatial structure representation. The article discusses a procedure of constructing a stochastic spatial process model, and analyses the most important problems that arise during the specification, estimation and validation of the model. The Polish contribution to solving theoretical questions related to the modeling of spatial structures and processes was also emphasized.
PL
Niniejsze opracowanie jest przeglądem wybranych zagadnień z zakresu modelowania matematyczno-statystycznego struktur i procesów przestrzennych. Ogólny charakter tego artykułu obejmuje dyskusję nad podstawowymi pojęciami, takimi jak: układ przestrzenny, struktura przestrzenna, proces przestrzenny, i ich wzajemnymi relacjami. Następnie definiowany jest w sposób ogólny (stochastyczny) proces przestrzenny i jego składniki, ze szczególnym uwzględnieniem reprezentacji struktury przestrzennej. Artykuł omawia sposób budowy modelu stochastycznego procesu przestrzennego, analizując jednocześnie najważniejsze problemy pojawiające się na etapie jego specyfikacji, estymacji i weryfikacji. Uwypuklono również wkład poznańskich geografów w rozwiązywanie problemów teoretycznych związanych z modelowaniem struktur i procesów przestrzennych.
EN
Cocoa remains in the same field for decades, resulting in plantations dominated with aging trees growing on variable and depleted soils. We determined the spatio-temporal variability of key soil properties in a (5.81 ha) field from the International Cocoa Genebank, Trinidad using geophysical methods. Multi-year (2008-2009) measurements of apparent electrical conductivity at 0-0.75 m (shallow) and 0.75-1.5 m (deep) were conducted. Apparent electrical conductivity at deep and shallow gave the strongest linear correlation with clay-silt content (R = 0.67 and R = 0.78, respectively) and soil solution electrical conductivity (R = 0.76 and R = 0.60, respectively). Spearman rank correlation coefficients ranged between 0.89-0.97 and 0.81-0.95 for apparent electrical conductivity at deep and shallow, respectively, signifying a strong linear dependence between measurement days. Thus, in the humid tropics, cocoa fields with thick organic litter layer and relatively dense understory cover, experience minimal fluctuations in transient properties of soil water and temperature at the topsoil resulting in similarly stable apparent electrical conductivity at shallow and deep. Therefore, apparent electrical conductivity at shallow, which covers the depth where cocoa feeder roots concentrate, can be used as a fertility indicator and to develop soil zones for efficient application of inputs and management of cocoa fields.
EN
Cuscuta species are interestingly behaving plant parasites of very different plant communities all over the world. Under warmer climate conditions they can act as dangerous pests, while in the northern countries they are considered as threatened species. Moreover these plants have a special strategy to find their host, called foraging. Chemical clues emitted by the host plants attract the parasite shoots to the most proper host. Recent papers investigate the host preference of Cuscuta species. In our research, we examine the appearing spatial patterns with both experimental and modelling tools. Our objective is to reproduce this phenomenon in the virtual space and find the model, which best describes the emerging spatial patterns. For the modelling cellular automata are used, which are commonly used tools in spatial ecology. These are spatially explicit dynamic models, where both time and space are discrete. The graphical representation is a squared lattice. Every square – also called cell – in the lattice has a state (e.g. soil, plant, parasite) represented with an appropriate colour. In this paper we present the results of our field observations as well as the mathematical models considered.
EN
Mute Swan Cygnus olor numbers have recently increased in a dramatic fashion in Western Europe and in North America, suggesting there could be potential consequences for the rest of the waterbird community. Breeding Mute Swan pairs may behave territorially towards other waterbirds, taking advantage of their larger size, and hence cause concern regarding their potential effects on waterbird communities. We studied how the within-site distributions of breeding Mute Swans and other waterbirds were related to each other, in order to assess if there is support to the assertion that breeding Mute Swans may affect the distribution of the other waterfowl within waterbodies. We mapped waterbird and swan distribution within fishponds during the Mute Swan breeding period. Relying on spatial point pattern analysis, our first finding is that breeding Mute Swans were located in the vicinity of the other waterbirds, using the same area within fishpond. Waterbirds do not completely desert the area used by breeding swan pairs within a waterbody, hence not supporting the claim that Mute Swans dislodge the other species. If an exclusion process by Mute Swan breeding pairs towards waterbirds exists, it is not strong enough to generate deserted areas by waterbirds around breeding Mute Swans. Our second finding is that breeding Mute Swans were not located where the density probability function for waterbird presence was the greatest within a fishpond, i.e. breeding Mute Swans were not located in the centre of groups formed by other waterbirds within each fishponds. This may indicate slightly different micro-habitat preferences or use within fishponds, or could indicate the potential occurrence of interactions. In conclusion, these results question whether the increasing Mute Swan populations actually directly threaten the other waterbird communities in such habitats, and require population control as is often claimed.
PL
Liczebność łabędzia niemego w ostatnich latach drastycznie wzrosła w Europie Zachodniej i Ameryce Północnej, co może wpływać na resztę zespołu ptaków wodnych. Łabędzie nieme mogą wywierać wpływ na inne ptaki wodne pośrednio poprzez zmniejszenie ilości dostępnego pokarmu, a także bezpośrednio poprzez agresywne zachowania terytorialne. Zachowania terytorialne zaobserwowano np. na zbiornikach wodnych na terenach, na których łabędź niemy uważany jest za gatunek inwazyjny. Jednocześnie w innym badaniu stwierdzono większą liczebność ptaków wodnych na zbiornikach, na których występowały lęgowe łabędzie nieme. Ogólnie jednak niewiele jest wiadomo na temat potencjalnego wpływu zachowań terytorialnych łabędzi na rozmieszczenie pozostałych ptaków wodnych. W pracy badano czy istnieje zależność pomiędzy rozmieszczeniem lęgowych łabędzi niemych i innych ptaków wodnych (rozpatrywano kaczki pływające i nurkujące oraz łyski) w obrębie tego samego zbiornika wodnego. Badania prowadzono na stawach rybnych (o średniej powierzchni 9,9 ha) we wschodniej Francji, prowadząc trzykrotne mapowanie wszystkich ptaków wodnych na danym zbiorniku. Terminy kontroli dopasowano do cyklu lęgowego łabędzi: pierwsza kontrola została przeprowadzona w okresie wysiadywania, druga w okresie wykluwania się piskląt, a trzecia, gdy łabędzie wodzą pisklęta (Tab. 1). Analizy przeprowadzono za pomocą analizy rozmieszczenia danych punktowych w przestrzeni, w której jako punkty oznaczono lokalizację pojedynczych ptaków lub w niektórych przypadkach grupę ptaków (np. para ptaków, samica z pisklętami) (Fig. 1). Stwierdzono, że na terenie badanych zbiorników wodnych łabędzie przebywały blisko siebie (Fig. 2). Łabędzie stwierdzano w sąsiedztwie innych ptaków wodnych, wykorzystywały one ten sam obszar w obrębie danego zbiornika. Takie rozmieszczenie skupiskowe obserwowano do 175 m (Fig. 3). Inne ptaki wodne nie unikają stref wykorzystywanych przez lęgowe łabędzie, co nie potwierdza sugestii, że łabędzie mogą wypierać inne gatunki. Nawet, jeśli istnieje pewne unikanie lęgowych łabędzi przez inne ptaki wodne, nie jest ono na tyle silne, aby generować obszary, na których nie obserwuje się innych ptaków wodnych. Analizy wskazują także, że łabędzie nie były zlokalizowane w centrum grup utworzonych przez inne ptaki wodne w obrębie każdego stawu (Fig. 4, 5). Może to wskazywać na nieco inne preferencje mikrosiedliskowe lub sposoby użytkowania przestrzeni stawów oraz występowanie potencjalnych interakcji. Podsumowując, autorzy wskazują, że łabędzie prawdopodobnie bezpośrednio nie wpływają na inne ptaki wodne, a więc populacje łabędzi nie wymagają działań mających na celu kontrolę ich liczebności, jak często się twierdzi.
EN
In July, 1992, fire swept through the Jelonka Reserve (52o35'33"N; 23o22'10"E). Litter, herbs layer and juniper shrubs were razed and the tree trunks of Pinus sylvestris and Populus tremula damaged, which resulted in their death the following year. Five research plots of 25 m2 each were established in the post-fire area. The species present there and their degrees of coverage were listed on the Londo scale between 1993 and 2002. The calculation of average degrees of coverage for individual populations allowed for the establishing of a chronological pattern of post-fire succession. The following findings have been made: 1) the primary function in colonization belongs to species of guerilla strategy of growth whose dormant buds survived fire underground (Holcus mollis, Calluna vulgaris and Populus tremula) or phalanx strategy of growth (Corynephoms canescens); 2) the dominants of the initial succession stage are perennial grasses, not therophytes; 3) the spatial pattern of succession is influenced by the occurrence of H. mollis or C. canescens in a particular location; 4) the initial stage terminates with the occurrence and further growth of C. vulgaris clumps; the post-fire succession in the Jelonka Reserve attained a brushwood stage faster in comparison to secondary succession, formerly triggered by the cessation of cultivation on arable land.
EN
European beech is a superior competitor among the trees of Central Europe, often growing in pure stands. We proposed a hypothesis, that once beech has reached dominance in forest community, it's recruitment could become limited due to the gradual accumulation of pathogens attacking seeds and seedlings. We employed data on seed production and germination along with a field experiment to estimate the germination success of beech in two old-growth forests. Beech produced more seeds than the co-occurring coniferous trees, but less than 1% of beechnuts germinated in the next season. In the field experiment, the percentage of decayed beechnuts was 57% in the Carpathians and 61% in the Alps. Most of the dead germinants and decayed beechnuts were infested by fungi. The average number of fungal colonies per one sample in the Carpathians was significantly higher after mast year than one year before, while the differences between the Alps and Carpathians after mast years were statistically not significant. Fungi have been isolated from practically all dead beechnuts and dead germinants. The number of beechnuts per seed trap, the number of germinants around it and the relative number of fungal colonies obtained from plastic boxes placed in the same sample plot were not significantly correlated. The mortality of germinants continued throughout the spring; the number of life germinants in the middle of May amounted to 0.87% of the initial number of beechnuts in the Carpathians and only 0.28% in the Alps. High rates of beechnut and germinant mortality could probably offset the huge reproductive effort of European beech in old-growth stands and limit the possibility to attain absolute dominance by that species. However, our hypothesis that the build-up of fungal pathogens on the forest floor old-growth stands is able to stop the regeneration of beech still needs to be tested using larger data sets.
11
Content available remote Logistic equations in tumour growth modelling
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EN
The aim of this paper is to present some approaches to tumour growth modelling using the logistic equation. As the first approach the well-known ordinary differential equation is used to model the EAT in mice. For the same kind of tumour, a logistic equation with time delay is also used. As the second approach, a logistic equation with diffusion is proposed. In this case a delay argument in the reaction term is also considered. Some mathematical properties of the presented models are studied in the paper. The results are illustrated using computer simulations.
EN
While the knowledge about spatial structure of zooplankton communities in large rivers has been relatively well studied, little is known on the longitudinal spatial variation of zooplankton in small, slowly flowing fishless streams. In these streams, changes in zooplankton communities along entire length of the stream can be quite different than in those where young planktivorous stages of fish reduce the abundance of zooplankton. The aim of this study was to answer the following questions. What is the spatial pattern of the taxonomic groups of zooplankton in the slow-flowing stream? Do the small tributaries have an impact on the zooplankton community in the main stream? What biotic variables (content of chlorophyll a, vegetation coverage, macroinvertebrates abundance) and abiotic variables (temperature, dissolved oxygen, pH, conductivity, N-NO3, N-NO2, N-NH3, TN, P-PO4, TP, width, depth, current velocity, discharge) most affect the zooplankton community in a small stream? This study was performed at six sites along a small (1 km long, mean width 1.7 m; mean depth 0.3 m; mean current velocity 5.9 cm s-1; mean discharge 2.6 cm3 s-1, mean vegetation coverage 52%) fishless agricultural-meadow stream and at one site in its two tributaries. The stream was searched with the use of electric fish gear to make sure there were no fish. Zooplankton samples were collected each month throughout the years 2008 and 2009. The main factors which affected the zooplankton communities were hydrological conditions, especially current velocity. Water current in the stream impeded the movement of rotifers and juvenile copepods. Adult copepods were able to manage in the current, over the entire length of the stream. Cladocerans probably were only able to persist in the last section of the watercourse flow, where the velocity was the lowest (3.3 cm s-1) and where the content of chlorophyll a was the highest (56.2 μg L-1 ). The two tributaries had only a small effect on shaping of the zooplankton communities in the main stream. On the basis of Pearson correlations it can be concluded that macroinvertebrate had a low ability to reduce the density of zooplankton, all significant correlations between the abundance of potamozooplankton and that of macroinvertebrates were positive.
EN
The present research was conducted in managed stands of Scots pine (Pinus sylvestris L.) at different age in Poland. All the investigated stands were planted and thinned according to selection thinning. Analysis of spatial structure concerned trees of different categories (DBH classess) depending on the age of stand. Spatial distribution of trees was investigated using two commonly used methods: Clark-Evans R index and Ripley's L(t) function. In stands of age 43 and 65 the effect of the initial spacing was observed and all living trees were distributed regularly at the smallest distances and at larger spatial scale they were spaced randomly. Random type of spatial structure of trees was observed when smaller and larger trees were taken into consideration, separately. In case of stands at the age 90 the effect of the initial planting on the spatial structure of trees was not observed even at the smallest distances independently of the category of trees taken into account. All living trees in these stands were distributed randomly. Only in two stands clumps of trees were observed and one concerned smaller trees and the other - larger trees. Size differentiation index was small for all stands. The lowest values was ascertained in the oldest stands.
PL
Celem pracy było określenie wzorca przestrzennego rozmieszczenia drzew na powierzchni oraz przestrzennego zróżnicowania ich pierśnic w drzewostanach gospodarczych (Pinus sylvestris L.) sosny zwyczajnej zlokalizowanych w Nadleśnictwie Wymiarki, RDLP Zielona Góra. Analiza dotyczyła drzewostanów w wieku 43, 65 oraz 90 lat, rosnących na siedlisku BMśw, w których były prowadzone zabiegi pielęgnacyjne zgodnie z regułami obowiązującymi w Lasach Państwowych. Typ poziomego rozmieszczenia osobników określono z wykorzystaniem dwóch popularnych metod: indeksu Clarka- -Evansa (R) oraz funkcji Ripleya [Clark i Evans 1954, Donnelly 1978, Moeur 1993]. Analizie poddano wszystkie drzewa żywe, drzewa cieńsze od średniej pierśnicy oraz drzewa grubsze od tej średniej dla poszczególnych drzewostanów. Przestrzenne zróżnicowanie pierśnic określono na podstawie indeksu zróżnicowania przestrzennego TD [Pommerening 2002], W drzewostanach w wieku 43 i 65 lat obie metody określenia typu poziomej organizacji przestrzennej pozwoliły stwierdzić regularne ich rozmieszczenie w małej skali przestrzennej. W drzewostanie najstarszym (90 lat) nie wykazano istotnych odchyleń od wzorca teoretycznego populacji rozmieszczonej losowo (tab. 1, rys. 1, 2). W drzewostanach w wieku 43 i 65 lat rozmieszczenie drzew należących do kategorii drzew cieńszych niż średnia, w większości nie różniło się od losowego. Stwierdzana regularność była obserwowana jedynie w najmniejszej skali przestrzennej. Drzewa grubsze od średniej pierśnicy w tych drzewostanach były rozmieszczone równie często losowo, co regularnie. Podobnie jak w drzewach cieńszych, regularność przejawiała się jedynie w skali przestrzennej odpowiadającej najbliższemu sąsiedztwu (tab. 1, rys. 1, 2). W drzewostanach najstarszych (90-letnich) drzewa cieńsze i grubsze od średniej najczęściej byly rozmieszczone losowo. Mimo że wartości indeksu R wskazywały na rozmieszczenie grupowe drzew obu kategorii, zostało ono potwierdzone statystycznie tylko w jednym drzewostanie i tylko dla drzew cieńszych (tab. 2, rys. 3). Przestrzenne zróżnicowanie pierśnic najbliższych sąsiadów było niewielkie i z wiekiem malało we wszystkich badanych drzewostanach (tab. 1).
EN
Evapotranspiration values (ET) are crucial for agriculture where estimates of water reserves available for crops are the basis for scheduling the time and intensity of irrigation, yield prognoses, etc. Detailed evapotranspiration data are, therefore, of essential value. However, stations performing direct measurements of evapotranspiration are very scarcely distributed in Poland, and for this reason the interpolation of data is necessarily biased. Hence, evapotranspiration values are calculated using indirect methods (usually empirical formulas). Data from geostationary meteorological satellites are used operationally for the determination of evapotranspiration with good spatial and temporal resolution (e.g. Land-SA F product). The study of the relation between evapotranspiration values determined with the use of satellite data and those calculated using the Penman-Monteith formula was performed for the study area in Poland. Daily values and cumulated (i.e. decadal, monthly and yearly) values were analysed to determine the quality and possible added value of the satellite product. The relation between the reference ET and actual ET in two consecutive years was discussed, both for the whole test area and for individual stations, taking into account land use and possible water deficit in the root zone, represented by H-SA F (EUMETSA T Satellite Application facility supporting Operational Hydrology and Water Management) soil wetness index product. The differences are presented and discussed.
EN
Scats are important for chemical communication in many canids, however, little is known about the faecal marking behaviour in coyotes. In this study we tested if faeces have a function as visual and scent marks during the non-breeding period, analyzing the spatial characteristics of defecation places. We predicted that if faeces are used as chemical signals, these should be deposited in substrates and/or zones that enhance their detection by conspecifics as it happens in other canid species. The study was conducted in native grasslands at the NW limit of the Chihuahuan Desert. Results showed that the proportion of faeces in conspicuous zones (91.3%) was significantly higher than those on inconspicuous zones (8.7%). However, the number of faeces deposited on inconspicuous substrates (92.1%) was significantly higher than on conspicuous substrates (7.9%). Most faeces were on the ground (99.2%) and only 0.8% where raised. 35% of faeces were deposited in crossroads, being these strategic zones repeatedly marked by the coyotes. We observed a significant negative correlation between the number of faeces in crossroads and the distance of faeces to the centre of the crossroad. A high number of scats were found in the proximity of livestock carcasses (21%). In addition, a selection of certain road sections (track and lateral) was observed. Our results suggest that the scats have an important function as scent-marks in coyotes, using specific defecation patterns that appear to correspond to the habitat characteristics in the study area.
EN
To understand the relationship between social behaviour and gene distribution, we used microsatellite markers to resolve the spatial genetic structure of the sika deerCervus nippon Temminck, 1838 population on Kinkazan Island, a small island (9.6 km2) in northern Japan. We obtained 177 samples of deer which correspond to about 30% of the total population on the island. 126 were from a local population where each deer was individually identified, while 51 from other area on the island. Although there were no apparent geographical barriers on the island, the sika deer population showed local differentiation in its genetic composition. By comparing allele-sharing rates between gender and social categories, we demonstrated a higher genetic relatedness within males in a local group. The Assignment Index (AI) of each sex within a local group showed similar distributions. None of our analyses indicated a lower genetic relatedness among males than females, which contradicted our predictions based on the dispersal behaviour of males. Considering other factors, the results suggest that the range of male dispersal is quite limited on this island.
EN
We make an attempt to consolidate results from a number of recent studies into spatial patterns of temporal variations in Baltic Sea wave properties. The analysis is based on historically measured and visually observed wave data, which are compared with the results of numerical hindcasts using both simple fetch-based one-point models and contemporary spectral wave models forced with different wind data sets. The focus is on the eastern regions of the Baltic Sea and the Gulf of Finland for which long-term wave data sets are available. We demonstrate that a large part of the mismatches between long-term changes to wave properties at selected sites can be explained by the rich spatial patterns in changes to the Baltic Sea wave fields that are not resolved by the existing wave observation network. The spatial scales of such patterns in the open sea vary from >500 km for short-term interannual variations down to about 100 km for long-term changes.
EN
In this study, we investigated the interactions between the dominant native invader, Gundelia tournefortii, and the dominant forage species, Psathyrostachys fragilis in rangelands of Taleghan (Iran). Four transects of 150 meters were considered as sampling unit. Using randomly-systematic method, 15 plots (1 × 1m) were placed along each transect with a distance of 10 m. List of species, the canopy cover and the numbers of plant species were determined in each plot. The spatial association of the two dominant species was assessed by studying association, covariation, and distribution pattern (using the Hopkins’ index) of plants. We found a clumped distribution pattern in both two dominant species. Results of this study revealed a strong competitive interaction between the dominant plant species in studied area with P. fragilis was more frequent and had more canopy cover than the native invader G. tournefortii. So, according to our findings, P. fragilis may present a suitable candidate for artificial re-vegetating and protecting against invaders to restore the biodiversity and ecological health of endangered rangelands.
EN
The foraging behavior of greater short-nosed fruit bats (Cynopterus sphinx) on wild banana (Musa acuminata) and subsequent dispersal of seeds were studied in the Tropical Rainforest Conservation Area, Xishuangbanna Tropical Botanical Garden, Yunnan province, by direct observation of marked fruits, mist netting, and seed collection. The mean number (± SE) of individual C. sphinx captured by mist net were 2.2 ± 0.33/day and 1.4 ± 0.32/day in the rainy season (September to October) and dry season (November to December), respectively; the difference was not significant. The number of seed pellets expelled was 9.0 ± 1.12/day and 7.2 ± 1.37/day in the rainy and dry seasons respectively; again the difference was not significant. The removal curves for marked fruit were similar for 10 focal trees. Fruits were consumed heavily within two weeks after ripening and all the marked fruit were removed within one month. The difference in seed dispersal was significant between different feeding roosts indicating that patterns of seed dispersal may not be uniform. We found the seeds of M. acuminata can be dispersed by C. sphinx to a distance of about 200 m, and C. sphinx can be considered as an effective seed disperser of M. acuminata.
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