Faunal provinces in Canada as exemplified by mammals and birds: a mathematical consideration

1972 ◽  
Vol 50 (8) ◽  
pp. 1087-1104 ◽  
Author(s):  
Gary W. Kaiser ◽  
Leonard P. Lefkovitch ◽  
Henry F. Howden
Keyword(s):  
Species Composition ◽  
Species Density ◽  
Passerine Birds ◽  
Rates Of Change ◽  
Mathematical Techniques ◽  
Taxonomic Groups ◽  
Composition Changes ◽  
Sharp Breaks

Although different regions have a characteristic fauna, mathematical techniques based on rates of change in composition, changes in species density, and similarity of composition do not give unequivocal definitions of faunal provinces. There is some concordance between species consistency of large taxonomic groups (mammals, passerine, and non-passerine birds) and the ecological pressures exerted on the groups. Changes in species composition are characterized by gradual shifts over large zones of transition and not by sharp breaks between close homogeneous areas, so that no provinces or divisions are clearly defined.

scholarly journals Multi-taxa ecological responses to habitat loss and fragmentation in western Amazonia as revealed by RAPELD biodiversity surveys

2021 ◽  
Vol 51 (3) ◽  
pp. 234-243
Author(s):  
Gabriel M. MOULATLET ◽  
Emmanuel AMBRIZ ◽  
Jennifer GUEVARA ◽  
Karima G. LÓPEZ ◽  
Marina RODES-BLANCO ◽  
...  
Keyword(s):  
Species Composition ◽  
Habitat Loss ◽  
Forest Cover ◽  
Landscape Fragmentation ◽  
Dung Beetles ◽  
Landscape Configuration ◽  
Edge Density ◽  
Logistic Regression Models ◽  
Habitat Loss And Fragmentation ◽  
Taxonomic Groups

ABSTRACT Habitat loss and fragmentation caused by deforestation are important anthropogenic drivers of changes in biodiversity in the Amazon rainforest, and has reached its highest rate in recent decades. However, the magnitude and direction of the effects on species composition and distribution have yet to be fully understood. We evaluated the responses of four taxonomic groups − birds, amphibians, orchid bees, and dung beetles - to habitat loss and fragmentation at both species and assemblage level in the northern Ecuadorian Amazon. We sampled fifteen 250-m long plots in terra-firme forest remnants. We calculated one landscape fragmentation index (fragindex), which considers the proportion of continuous forest cover, edge density and isolation in the landscape, and nine landscape configuration metrics. Logistic regression models and multivariate regression trees were used to analyze species and assemblage responses. Our results revealed that over 80% of birds, amphibians or orchid-bee species, and 60% of dung beetles were negatively affected by habitat loss and fragmentation. Species composition of all taxonomic groups was significantly affected by differences in forest cover and connectivity. Less than 5% of all species were restricted to landscapes with fragindex values higher than 40%. Landscape metrics related to the shape and area of forest patches determined the magnitude and direction of the effect on species responses. Therefore, changes in the landscape configuration of Ecuadorian Amazonia should be minimized to diminish the effects of habitat loss and fragmentation on species occurrence and assemblage composition.

scholarly journals Short Communication: Application of artificial reefs for fisheries enhancement in Probolinggo, Indonesia

2019 ◽  
Vol 20 (8) ◽  
Author(s):  
Wahyu Isroni ◽  
SYIFANIA H. SAMARA ◽  
MUHAMMAD B. SANTANUMURTI
Keyword(s):  
Species Composition ◽  
Fish Species ◽  
Short Communication ◽  
Diversity Index ◽  
Species Density ◽  
Artificial Reefs ◽  
Lates Calcarifer ◽  
Dominance Index ◽  
Fish Species Composition ◽  
Fisheries Enhancement

Abstract. Isroni W, Samara SH, Santanumurti MB. 2019. Short Communication: Application of artificial reefs for fisheries enhancement in Probolinggo, Indonesia. Biodiversitas 20: 2273-2278. Overfishing is one of the biggest challenges in the fisheries sector in Probolinggo, Indonesia. The fish apartment (artificial reefs) was one of the solutions to increase the fish resource since it serves as the habitat for fish to live, spawn, and search for food. In this study, the fish apartment was installed in Probolinggo (Karang Katon and Dringu Beach) from 2017 to 2018. This study showed that five fish species (Caesio cuning, Acanthurus achilles, Acanthurus albipectoralis, Sphyraena jello, and Apagon novemfasciatus) were found in Karang Katon while four species (Chaetodon octofasciatus, Chromobotia macracanthus, Nemipterus japonicas, and Lates calcarifer) lived in Dringu Beach. From a total of 333 fishes, A. achilles was the species with the highest composition level of 51.65% (172) in Karang Katon station. In Dringu Beach station, C. octofasciatus had the highest fish species composition level of 46% (183) from a total of 402 fishes. The diversity index and dominance index in Karang Katon station were low at-1.280 and 0.343, respectively. The diversity index and dominance index in Dringu Beach station were also low at -1.115 and 0.3503. A. achilles had the highest density of 34.4 ind/m3 in Karang Katon station while C. octofasciatus had the highest species density of 36.6 ind/m3 in Dringu Beach Station. From this study, it could be concluded that artificial reefs application enhanced the fisheries in Probolinggo, Indonesia, and help its sustainability.

scholarly journals Functional Composition Changes of a Subtropical Monsoon Evergreen Broad-Leaved Forest Under Environmental Change

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 191
Author(s):  
Shun Zou ◽  
Qianmei Zhang ◽  
Guoyi Zhou ◽  
Shizhong Liu ◽  
Guowei Chu ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Drought Tolerance ◽  
Species Composition ◽  
Environmental Change ◽  
Subtropical Forest ◽  
Functional Composition ◽  
Composition Change ◽  
Environment Change ◽  
Soil Dryness ◽  
Composition Changes

Long-term studies have revealed that forest species composition was shifting under environment change and disturbance induced by loss of large trees. Yet, few studies explicitly analyzed their impacts on composition concurrently. To learn more about impacts of environment change and disturbance on driving forest community, we investigated shifts in functional composition over past 24 years in an old-growth subtropical forest in southern China. We analyzed nine traits that are mainly related to leaf nutrients, photosynthetic capacity, hydraulic conductivity, and drought tolerance of plants and examined hypotheses: (1) The functional composition change over time was directional instead of random fluctuation, (2) drought-tolerant species increased their abundance under soil dryness, (3) both environmental change and disturbance related to changes of functional composition significantly, and (4) initial trait values of quadrats strongly influenced their subsequent change rates in quadrat level (10 × 10 m). We found that species composition had shifted to favor species with high leaf nutrient content, high photosynthesis rate, high hydraulic conductivity, low water-use efficiency, and high drought tolerance traits, which was due to soil dryness and disturbance. These two factors explained 47–58% of quadrats’ trait value changes together. Considering rapidly increasing stem density, this pattern may indicate ecological processes of which disturbance provided numerous recruits of resource-acquisition strategy species and soil dryness conducted a selecting effect on shaping composition in the forest. Additionally, quadrats with initial trait values at the far end of change direction shifted faster in three traits, which also indicated that functional composition changes in quadrats were directional and homogenized. Our results implied that environment change and accompanied disturbance events possibly drove species composition change along a different trajectory in the subtropical forest that experienced high climatic variability.

scholarly journals Dynamics of stand composition changes in grass and grass-clover stands and relations between dominant species

2011 ◽  
Vol 49 (No. 3) ◽  
pp. 119-125
Author(s):  
P. Matušinsky ◽  
F. Hrabě
Keyword(s):  
Species Composition ◽  
Dominant Species ◽  
Grass Species ◽  
Individual Species ◽  
Yield Parameters ◽  
Method Of Determination ◽  
Subsequent Comparison ◽  
Composition Changes ◽  
Good Agreement

Changes in the species composition of temporary grass and grass-clover crops stands were studied in 1994–2000. The assessment consisted in determination of the dominance of individual species, measurement of their aboveground biomass weight and subsequent comparison of detected values. The measurements were evaluated by the method of determination of distance between vectors of stand composition and by the subsequent standardization. Resulting values are in a good agreement with the hither to knowledge and confirm that more favourable yield parameters are achieved within 30–60% of total changeability. Changes of species composition and stand changeability are at their initial stages of succession given by external changes mainly contributed to by the group of clumpy grass species and by internal changes within the group of pod-bearing plants.

scholarly journals The Living Planet Index: using species population time series to track trends in biodiversity

2005 ◽  
Vol 360 (1454) ◽  
pp. 289-295 ◽  
Author(s):  
Jonathan Loh ◽  
Rhys E Green ◽  
Taylor Ricketts ◽  
John Lamoreux ◽  
Martin Jenkins ◽  
...  
Keyword(s):  
Time Series ◽  
Time Series Data ◽  
Series Data ◽  
Tropical Species ◽  
Rates Of Change ◽  
Threat Status ◽  
New Information ◽  
Linear Modelling ◽  
Species Population ◽  
Taxonomic Groups

The Living Planet Index was developed to measure the changing state of the world's biodiversity over time. It uses time-series data to calculate average rates of change in a large number of populations of terrestrial, freshwater and marine vertebrate species. The dataset contains about 3000 population time series for over 1100 species. Two methods of calculating the index are outlined: the chain method and a method based on linear modelling of log-transformed data. The dataset is analysed to compare the relative representation of biogeographic realms, ecoregional biomes, threat status and taxonomic groups among species contributing to the index. The two methods show very similar results: terrestrial species declined on average by 25% from 1970 to 2000. Birds and mammals are over-represented in comparison with other vertebrate classes, and temperate species are over-represented compared with tropical species, but there is little difference in representation between threatened and non-threatened species. Some of the problems arising from over-representation are reduced by the way in which the index is calculated. It may be possible to reduce this further by post-stratification and weighting, but new information would first need to be collected for data-poor classes, realms and biomes.

Monitoring protozoa and metazoa biofilm communities for assessing wastewater quality impact and reactor up-scaling effects

2000 ◽  
Vol 41 (4-5) ◽  
pp. 309-316 ◽  
Author(s):  
J. Fried ◽  
G. Mayr ◽  
H. Berger ◽  
W. Traunspurger ◽  
R. Psenner ◽  
...  
Keyword(s):  
Species Composition ◽  
Large Scale ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Plant Performance ◽  
Scaling Effects ◽  
Wastewater Quality ◽  
Biofilm Structure ◽  
Composition Changes ◽  
Up Scaling

The succession of biofilm communities with special emphasis on ciliates, rotifers, and nematodes was monitored for half a year and compared to different operating conditions in order to evaluate plant performance and effect of up-scaling lab scale to large scale reactors. Ciliates and metazoa are able to rapidly change their communities as a reaction to changed plant operating conditions as has been proven true by comparing lab scale and pilot scale reactors. Even slight operational changes are causing major shifts in biofilm communities. Nematodes and rotifers in lab scale and large scale reactors seem to be in competition with peritrich ciliates. In both lab scale and pilot scale systems ciliates of the subclass Peritrichia proved to be dominant and thus to play an important role in both the species composition of the biofilm biocenosis and biofilm structure. Interpretation of biocenosis composition changes for large scale reactors is much more complex than for lab scale reactors. This conflicts with up-scaling of lab scale results to full scale reactors.

scholarly journals The influence of the type of storage on pest infestation of stored grain in the Czech Republic

2011 ◽  
Vol 49 (No. 2) ◽  
pp. 55-62 ◽  
Author(s):  
V. Stejskal ◽  
J. Hubert ◽  
Z. Kučerová ◽  
Z. Munzbergová ◽  
J. Lukáš ◽  
...  
Keyword(s):  
Species Composition ◽  
Sitophilus Oryzae ◽  
Rhyzopertha Dominica ◽  
Economic Losses ◽  
Pest Species ◽  
Stored Grain ◽  
Acarus Siro ◽  
Pest Infestation ◽  
Grain Stores ◽  
Taxonomic Groups

Stored-product pests cause high economic losses by feeding on stored grain and endanger the public health by contamination of food by allergens. Therefore, the aim of this work was to explore whether the risk of infestation of stored grain by pests is different in various types of storage premises. We compared the level of infestation and the pest species composition in the two main types of grain stores in Central Europethat includes horizontal flat-stores (HFS) and vertical silo-stores (elevators) (VSS). A total of 147 grain stores located in  Bohemia, CzechRepublicwas inspected. We found that both types of stores were infested with arthropods of three main taxonomic groups: mites (25 species, 120 000 individuals), psocids (8 species, 5 600 individuals) and beetles (23 species, 4 500 individuals). We found that VSS and HFS differ in species composition of mites, psocids and beetles. However, the primary grain pests (i.e. Lepidoglyphus destructor, Acarus siro, Tyrophagus putrescentiae, Lachesilla pedicularia, Sitophilus oryzae, Rhyzopertha dominica, Oryzaephilus surinamensis and Cryptolestes ferrugineus) occurred in both types of stores. The only exception was higher frequency and abundance of two serious beetle-pests (Tribolium castaneum, Sitophilus granarius) in HFS than in VSS. The total numbers of mite and beetle species infesting VSS and HFS was almost the same. There was higher psocid species diversity in VSS than in HFS. The difference between the total (i.e. level of pest infestation per kg of grain sample) numbers of mite and psocid individuals collected from VSS and HFS was not significant. However, the total numbers of beetle-pest individuals collected from HFS was twice the amount collected from VSS. We concluded that both types of stores are equally risky in terms of mite and psocid infestation. HFS is more risky for grain storage than VSS in terms of beetle infestations, although even the VSS structures cannot be in no way called pest-safe. The VSS and HFS microclimatic conditions (humidity, temperature) are discussed in relation to mite, psocid and beetle infestation.

Sign in / Sign up

Export Citation Format

Share Document