scholarly journals Variability of contemporary vegetation around Petuniabukta, central Spitsbergen

2012 ◽  
Vol 33 (4) ◽  
pp. 383-394 ◽  
Author(s):  
Karel Prach ◽  
Jitka Klimešová ◽  
Jiří Košnar ◽  
Olexii Redčenko ◽  
Martin Hais
Keyword(s):  
High Latitude ◽  
Vascular Plants ◽  
Native Species ◽  
Spatial Scales ◽  
A Priori ◽  
Vegetation Pattern ◽  
Svalbard Archipelago ◽  
Species Lists ◽  
Phytosociological Relevés ◽  
First Time

Abstract Vegetation was described in various spatial scales in the area of 37.8 km2 including distinguishing vegetation units, vegetation mapping, recording phytosociological relevés (53), and completing species lists of vascular plants (86), mosses (124) and lichens (40). Phytosociological relevés were elaborated using ordination methods DCA and CCA. The relevés formed clusters corresponding well to a priori assigned vegetation units. Slope and stoniness significantly influenced the vegetation pattern. Despite the high latitude (nearly 80° N), the vegetation is rather rich in species. Non-native species do not expand. The moss Bryum dichotomum is reported for the first time from Svalbard archipelago.

scholarly journals Convolutional Neural Networks Predict Fish Abundance from Underlying Coral Reef Texture

2018 ◽  
Author(s):  
Grace Young ◽  
Vassileios Balntas ◽  
Victor Prisacariu
Keyword(s):  
Spatial Scales ◽  
A Priori ◽  
3D Structure ◽  
Three Dimensional ◽  
Structural Complexity ◽  
3D Models ◽  
Fish Abundance ◽  
Ecological Patterns ◽  
Abundance And Diversity ◽  
First Time

Coral reefs are among the most biodiverse ecosystems on Earth in large part owing to their unique three-dimensional (3D) structure, which provides niches for a variety of species. Metrics of structural complexity have been shown to correlate with the abundance and diversity of fish and other marine organisms, but they are imperfect representations of a surface that can oversimplify key structural elements and bias discoveries. Moreover, they require researchers to make relatively uninformed guesses about the features and spatial scales relevant to species of interest. This paper introduces a machine-learning method for automating inferences about fish abundance from reef 3D models. It demonstrates the capacity of a convolutional neural network (ConvNet) to learn ecological patterns that are extremely subtle, if not invisible, to the human eye. It is the first time in the literature that no a priori assumptions are made about the bathymetry–fish relationship.

scholarly journals An update to the species list of vascular plants of the spontaneous flora of the Left Bank Forest-Steppe of Ukraine

2021 ◽  
Vol 78 (1) ◽  
pp. 23-31
Author(s):  
D.A. Davydov ◽  
Keyword(s):  
Vascular Plants ◽  
New Records ◽  
Steppe Zone ◽  
Alien Plants ◽  
Forest Steppe ◽  
Left Bank ◽  
Species List ◽  
Species Lists ◽  
First Time ◽  
Rhododendron Tomentosum

Data on findings of seven species of vascular plants that are new records for the spontaneous flora of the Left Bank Forest-Steppe zone of Ukraine are presented. Four species (Artemisia umbrosa, Sedum album, Ribes aureum, and Prunus tomentosa) are alien plants completely naturalized in the studied area; other three species are treated by author as representatives of the indigenous fraction (Cerastium kioviense, Rhododendron tomentosum, and Vicia lathyroides). Cerastium kioviense and V. lathyroides are considered not rare species in the studied region but rather overlooked by botanists due to their early flowering period. Four species (A. umbrosa, C. kioviense, R. aureum, and P. tomentosa) were for the first time found in Poltava Region, two species (R. aureum, P. tomentosa) – in Kharkiv Region, and one (V. lathyroides) – in Kyiv Region. For all reported species, lists of their localities, places of original descriptions and nomenclatural types are indicated. The species name Prunus tomentosa is lectotypified.

scholarly journals The flora of Cunningham Inlet, Somerset Island, Nunavut: history, analysis, and new collections of vascular plants, mosses, lichens, and algae

2015 ◽  
Vol 129 (1) ◽  
pp. 24 ◽  
Author(s):  
Paul C. Sokoloff
Keyword(s):  
Vascular Plants ◽  
Vascular Plant ◽  
North Coast ◽  
University Of Alberta ◽  
Comprehensive Account ◽  
The North ◽  
National Herbarium ◽  
History Analysis ◽  
Somerset Island ◽  
First Time

New collections of vascular plants, bryophytes, lichen, and algae are reported for Cunningham Inlet on the north coast of Somerset Island, Nunavut. This list of 48 species of vascular plants, 13 bryophytes, 10 lichens, and five algae includes 136 specimens collected in 2013 and 39 previously unreported specimens from the National Herbarium of Canada at the Canadian Museum of Nature (CAN), Agriculture and Agri-Food Canada’s Vascular Plant Herbarium (DAO), and University of Alberta (ALTA). Ten vascular plants from previous collecting in 1958 are re-reported here to give a comprehensive account of the vascular plant flora of the region. Two vascular plants are recorded for the first time for Somerset Island: Smooth Draba (Draba glabella Pursh) and Edlund’s Fescue (Festuca edlundiae S. G. Aiken, Consaul & Lefkovitch).

scholarly journals Variability of the total ozone trend over Europe for the period 1950–2004 derived from reconstructed data

2008 ◽  
Vol 8 (11) ◽  
pp. 2847-2857 ◽  
Author(s):  
J. W. Krzyścin ◽  
J. L. Borkowski
Keyword(s):  
Total Ozone ◽  
A Priori ◽  
Smooth Curve ◽  
Ozone Level ◽  
Svalbard Archipelago ◽  
Small Areas ◽  
Ozone Data ◽  
Curve Fit ◽  
Long Term Changes

Abstract. The total ozone data over Europe are available for only few ground-based stations in the pre-satellite era disallowing examination of the spatial trend variability over the whole continent. A need of having gridded ozone data for a trend analysis and input to radiative transfer models stimulated a reconstruction of the daily ozone values since January 1950. Description of the reconstruction model and its validation were a subject of our previous paper. The data base used was built within the objectives of the COST action 726 "Long-term changes and climatology of UV radiation over Europe". Here we focus on trend analyses. The long-term variability of total ozone is discussed using results of a flexible trend model applied to the reconstructed total ozone data for the period 1950–2004. The trend pattern, which comprises both anthropogenic and "natural" component, is not a priori assumed but it comes from a smooth curve fit to the zonal monthly means and monthly grid values. The ozone long-term changes are calculated separately for cold (October–next year April) and warm (May–September) seasons. The confidence intervals for the estimated ozone changes are derived by the block bootstrapping. The statistically significant negative trends are found almost over the whole Europe only in the period 1985–1994. Negative trends up to −3% per decade appeared over small areas in earlier periods when the anthropogenic forcing on the ozone layer was weak . The statistically positive trends are found only during warm seasons 1995–2004 over Svalbard archipelago. The reduction of ozone level in 2004 relative to that before the satellite era is not dramatic, i.e., up to ~−5% and ~−3.5% in the cold and warm subperiod, respectively. Present ozone level is still depleted over many popular resorts in southern Europe and northern Africa. For high latitude regions the trend overturning could be inferred in last decade (1995–2004) as the ozone depleted areas are not found there in 2004 in spite of substantial ozone depletion in the period 1985–1994.

scholarly journals Using areas of known occupancy to identify sources of variation in detection probability of raptors: taking time lowers replication effort for surveys

2016 ◽  
Vol 3 (10) ◽  
pp. 160368 ◽  
Author(s):  
Campbell Murn ◽  
Graham J. Holloway
Keyword(s):  
Detection Probability ◽  
Spatial Scales ◽  
Survey Methods ◽  
A Priori ◽  
Low Density ◽  
Occupancy Models ◽  
Imperfect Detection ◽  
Factors Affecting ◽  
Sources Of Variation ◽  
Time Of Year

Species occurring at low density can be difficult to detect and if not properly accounted for, imperfect detection will lead to inaccurate estimates of occupancy. Understanding sources of variation in detection probability and how they can be managed is a key part of monitoring. We used sightings data of a low-density and elusive raptor (white-headed vulture Trigonoceps occipitalis ) in areas of known occupancy (breeding territories) in a likelihood-based modelling approach to calculate detection probability and the factors affecting it. Because occupancy was known a priori to be 100%, we fixed the model occupancy parameter to 1.0 and focused on identifying sources of variation in detection probability. Using detection histories from 359 territory visits, we assessed nine covariates in 29 candidate models. The model with the highest support indicated that observer speed during a survey, combined with temporal covariates such as time of year and length of time within a territory, had the highest influence on the detection probability. Averaged detection probability was 0.207 (s.e. 0.033) and based on this the mean number of visits required to determine within 95% confidence that white-headed vultures are absent from a breeding area is 13 (95% CI: 9–20). Topographical and habitat covariates contributed little to the best models and had little effect on detection probability. We highlight that low detection probabilities of some species means that emphasizing habitat covariates could lead to spurious results in occupancy models that do not also incorporate temporal components. While variation in detection probability is complex and influenced by effects at both temporal and spatial scales, temporal covariates can and should be controlled as part of robust survey methods. Our results emphasize the importance of accounting for detection probability in occupancy studies, particularly during presence/absence studies for species such as raptors that are widespread and occur at low densities.

scholarly journals Plant communities of the class Charetea Fukarek ex Krausch 1964 in Ukraine: an overview

2012 ◽  
Vol 25 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Dmytro Iakushenko ◽  
Olena Borysova
Keyword(s):  
Plant Communities ◽  
Submerged Plant ◽  
Phytosociological Relevés ◽  
First Time

Abstract The paper presents the results of the first syntaxonomical survey of the submerged plant communities belonging to the class of Charetea Fukarek ex Krausch 1964 in Ukraine based on the interpretation of about 80 published and unpublished phytosociological relevEs. Fourteen associations of two alliances and one order are characterized briefly. The diversity of charophyte communities in Ukraine is also described in brief. A preliminary prodromus of charophyte communities in Ukraine is given. Associations of Charetum intermediae (Corillion 1957) Fija≥kowski 1960, Charetum rudis Dπmbska 1966, Nitelletumgracilis Corillion 1957 are indicated for Ukraine for the first time.

scholarly journals Diversity of Segetal Flora in Salix viminalis L. Crops Established on Former Arable and Fallow Lands in Central Poland

Agriculture ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Maria Janicka ◽  
Aneta Kutkowska ◽  
Jakub Paderewski
Keyword(s):  
Native Species ◽  
Life Form ◽  
Arable Land ◽  
Salix Viminalis ◽  
Central Poland ◽  
Plant Groups ◽  
Fallow Lands ◽  
Historical Group ◽  
Phytosociological Relevés ◽  
Segetal Flora

The flora of willow (Salix viminalis L.) plantations consists of various plant groups, including plants related to arable land, called segetal plants. Knowledge of this flora is important for maintaining biodiversity in agroecosystems. The aim of the study was to assess the segetal flora of the willow plantations in central Poland, depending on the land use before the establishment of the plantations (arable land or fallow) and the age of the plantations. Moreover, the aim was also to check for the presence of invasive, medicinal, poisonous and melliferous species. The vegetation accompanying willow was identified based on an analysis of 60 phytosociological relevés performed using the Braun-Blanquet method. For each species, the following parameters were determined: the phytosociological class; family; geographical and historical group; apophyte origin; biological stability; life-form; and status as an invasive, medicinal (herbs), poisonous or melliferous species. The results were statistically processed. Segetal species accounted for 38% of the flora accompanying willow. The plantations on former arable land were richer in segetal species than those on fallow. Mostly, short-lived and native species dominated. In line with the age of the plantations, the number of segetal species decreased. The share of apophytes increased, and anthropophytes decreased. Furthermore, many valuable plants were found among the flora accompanying willow.

Mammal surveys in the forests of the Carrai Plateau and Richmond Range in north-east New South Wales.

1994 ◽  
Vol 17 (1) ◽  
pp. 19
Author(s):  
J. Barker ◽  
D. Lunney ◽  
T. Bubela
Keyword(s):  
Native Species ◽  
New South ◽  
New South Wales ◽  
North East ◽  
Mammal Fauna ◽  
South Wales ◽  
Species Lists ◽  
Fauna Composition ◽  
Eucalypt Forests ◽  
Open Forests

Mammal surveys were carried out on the Carrai Plateau and Richmond Range in north-east New South Wales between March 1988 and November 1989. The emphasis was placed on rainforest mammals, following the recognition by Adam ( 1987) that the species lists of mammals in the state's rainforests were incomplete and that more research was needed. The mammals were surveyed primarily by analysis of prey remains in Dog and Fox scats, collected from roads throughout the forests, and from bat trapping. The bat fauna at both the Carrai Plateau and Richmond Range is rich (1 0 species and nine species respectively, including the rare Golden-tipped Bat, Kerivoula papuensis, in the Richmond Range). Scat analysis revealed the presence of 24 native species on the Carrai Plateau, and on the Richmond Range there were 17 species, including high numbers of two pademelon species. Feral prey species are almost completely absent, although the Fox is an established predator in both areas. A sharp division was identified between the mammal faunas of closed and open forests. Differences were found also between the mammal fauna composition of the two rainforest sites, and with those of nearby eucalypt forests. The mammal fauna of New South Wales rainforests is distinct from open forests and future mammal surveys are needed to ensure an adequate level of knowledge to identify and conserve these areas.

Incomplete species lists derived from global and regional specimen-record databases affect macroecological analyses: A case study on the vascular plants of China

2018 ◽  
Vol 45 (12) ◽  
pp. 2718-2729 ◽  
Author(s):  
Hong Qian ◽  
Tao Deng ◽  
Jan Beck ◽  
Hang Sun ◽  
Cui Xiao ◽  
...  
Keyword(s):  
Vascular Plants ◽  
Species Lists ◽  
Specimen Record

scholarly journals Spatial scales of temperature and salinity variability estimated from Argo observations

2015 ◽  
Vol 12 (4) ◽  
pp. 1793-1814
Author(s):  
F. Ninove ◽  
P. Y. Le Traon ◽  
E. Remy ◽  
S. Guinehut
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Deep Ocean ◽  
General Tendency ◽  
Zero Crossing ◽  
Tropical Regions ◽  
Covariance Functions ◽  
Salinity Variability ◽  
First Time

Abstract. Argo observations from 2005 to 2013 are used to characterize spatial scales temperature and salinity variations from the surface down to 1500 m. Simulations are first performed to analyze the sensitivity of results to Argo sampling; they show that several years of Argo observations are required to estimate the spatial scales of ocean variability over 20° × 20° boxes. Spatial scales are then computed over several large scale areas. Zonal and meridional spatial scales (Lx and Ly which are also zero crossing of covariance functions) vary as expected with latitudes. Scales are of about 100 km at high latitudes and more of 700 km in the Indian and Pacific equatorial/tropical regions. Zonal and meridional scales are similar: except in these tropical/equatorial regions where zonal scales are much larger (by a factor of 2 to 3) than meridional scales. Spatial scales are the largest close to the surface and have a general tendency for temperature to increase in deeper layers. There are significant differences between temperature and salinity scales, in particular, in the deep ocean. Results are consistent with previous studies based on sparse in-situ observations or satellite altimetry. They provide, however, for the first time a global description of temperature and salinity scales of variability and a characterization of their variations according to depths.

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