scholarly journals Ecological investigation of Urpad beel: A major wetland of Goalpara district of Assam, India.

2018 ◽  
Vol 7 (4) ◽  
pp. 2112
Author(s):  
Upen Deka ◽  
Tapan Dutta
Keyword(s):  
Plant Community ◽  
Eichhornia Crassipes ◽  
Aquatic Macrophytes ◽  
Aquatic Plant ◽  
Ecological Study ◽  
Prime Factor ◽  
Diversity Index ◽  
Anthropogenic Activities ◽  
Diversity Indices ◽  
Life Forms

The present investigation deals with the ecological study of Urbad beel of Goalpara district of Assam with reference to aquatic plant community. The study was carried out during the year 2016 to 2017. Diversity indices viz. Shannon-Weiner diversity index, Simpson diversity index, Menhinick diversity index and Concentration of dominance were calculated to show the plant community structure of the wetland. A total of 93 aquatic macrophytic plant species belonging to 74 genera and 45 families have been reported from the wetland. Based on IVI value, Eichhornia crassipes was the most dominant species (IVI= 22.54) followed by Hygroryza aristata (IVI= 19.96), Arundo donax (IVI= 8.21) respectively whereas Cyperus brevifolius (IVI= 0.768) showed the lowest IVI value among all the life forms of the aquatic macrophytes of the wetland. Results showed that anthropogenic disturbances inside the wetland areas are the prime factor for losing aquatic plant community of the wetland. The obtained Shannon -diversity index values (3.06 and 2.18) both in summer and winter seasons indicate the further degradation of the wetland. Therefore, anthropogenic activities inside the wetland areas should be prevented for the sustainable existence of the wetland as well as the livelihood of the fringe villagers.

Diversity of macrophytes in the Amazon deforestation arc: information on their distribution, life-forms and habits

Rodriguésia ◽  
2021 ◽  
Vol 72 ◽  
Author(s):  
Ana Luísa Biondi Fares ◽  
Raimundo Luiz Morais de Sousa ◽  
Ely Simone Cajueiro Gurgel ◽  
André dos Santos Bragança Gil ◽  
Carlos Alberto Santos da Silva ◽  
...  
Keyword(s):  
Aquatic Ecosystems ◽  
Aquatic Macrophytes ◽  
Anthropogenic Activities ◽  
Life Forms ◽  
Biological Processes ◽  
Macrophyte Species ◽  
Form Part ◽  
Arc Of Deforestation ◽  
Northern Brazil ◽  
Suitable Habitats

Abstract The Amazon possesses the largest fluvial system on the planet, harboring a diverse biota. Still, many species remain undescribed, because of the Amazon’s immense scale and complexity, and because many habitats are now increasingly under pressure from anthropogenic activities. Macrophytes are important to physical and biological processes in aquatic ecosystems but remain poorly studied in Northern Brazil. The objective of this study was to provide a checklist of macrophyte species that occur in municipalities that form part of the Arc of Deforestation, Pará state, Brazil, bringing information on their habits and life-forms. We sampled 36 sites at three types of aquatic ecosystems (streams, ponds and lakes). In total, we recorded 50 species, 38 genera and 24 families. Most species were amphibious or emergent. Degraded streams have environmental characteristics similar to lentic habitats, which could provide more suitable habitats for macrophytes that otherwise would not occur in lotic habitats, thus explaining the higher diversity in these ecosystems. Macrophyte diversity in this region follows similar patterns to other Brazilian regions. This study contributes to the assessment of aquatic macrophytes in the Amazon, especially in more degraded regions, such as the Amazon deforestation arc.

scholarly journals Temporal and spatial patterns of aquatic macrophyte diversity in the Upper Paraná River floodplain

2009 ◽  
Vol 69 (2 suppl) ◽  
pp. 617-625 ◽  
Author(s):  
SM. Thomaz ◽  
P. Carvalho ◽  
AA. Padial ◽  
JT. Kobayashi
Keyword(s):  
Aquatic Macrophytes ◽  
Aquatic Macrophyte ◽  
Diversity Index ◽  
Species Turnover ◽  
Time Frame ◽  
Life Forms ◽  
Paraná River ◽  
River Floodplain ◽  
Parana River ◽  
Paraná River Floodplain

Although the importance of long-term data has been emphasized by ecologists in recent years, little is known about how communities may change over time. In this study, we describe the general patterns of aquatic macrophyte diversity in the Paraná River floodplain observed during six years of study. Temporal changes in community composition were also evaluated. Data on the presence or absence of aquatic macrophytes were collected between March 2002 and March 2008, in six lakes associated with three rivers. Different analytical strategies were used to evaluate the dynamics of aquatic macrophyte communities between the different systems in the floodplain. The composition of aquatic macrophytes differed among the rivers, mainly with respect to the different vegetation life forms (floating, submersed, emergent and rooted with floating stems). The temporal similarity of species composition during the six years and the beta-diversity index indicated that the month-to-month species turnover was, in general, lower in the connected lakes, which are directly influenced by the river. Probably the water level fluctuation is a selective force that contributes to maintaining diversity or richness. Our findings indicated the importance of abiotic characteristics and connectivity of the lakes in determining macrophyte composition and community stability over a long time frame.

scholarly journals Shifts in Rhizoplane Communities of Aquatic Plants after Cadmium Exposure

2005 ◽  
Vol 71 (5) ◽  
pp. 2484-2492 ◽  
Author(s):  
Lisa M. Stout ◽  
Klaus Nüsslein
Keyword(s):  
Bacterial Communities ◽  
Aquatic Plant ◽  
Lemna Minor ◽  
Diversity Index ◽  
Diversity Indices ◽  
Laboratory Culture ◽  
Contaminated Site ◽  
Community Studies ◽  
Plant Type ◽  
Dominant Group

ABSTRACT In this study we present the comparative molecular analysis of bacterial communities of the aquatic plant Lemna minor from a contaminated site (RCP) and from a laboratory culture (EPA), as well as each of these with the addition of cadmium. Plants were identified as L. minor by analysis of the rpl16 chloroplast region. Comparative bacterial community studies were based on the analyses of 16S rRNA clone libraries, each containing about 100 clones from the root surfaces of plants. Bacterial communities were compared at three phylogenetic levels of resolution. At the level of bacterial divisions, differences in diversity index scores between treatments, with and without cadmium within the same plant type (EPA or RCP), were small, indicating that cadmium had little effect. When we compared genera within the most dominant group, the β-proteobacteria, differences between unamended and cadmium-amended libraries were much larger. Bacterial diversity increased upon cadmium addition for both EPA and RCP libraries. Analyses of diversity at the phylotype level showed parallel shifts to more even communities upon cadmium addition; that is, percentage changes in diversity indices due to cadmium addition were the same for either plant type, indicating that contamination history might be independent of disturbance-induced diversity shifts. At finer phylogenetic levels of resolution, the effects of cadmium addition on bacterial communities were very noticeable. This study is a first step in understanding the role of aquatic plant-associated microbial communities in phytoremediation of heavy metals.

Abundance and nesting sites characteristics of red-headed picathartes Picathartes oreas in Cross River State, Nigeria

2021 ◽  
Vol 18 (1) ◽  
pp. 44-51
Author(s):  
M. Abatcha ◽  
O.S. Odewumi
Keyword(s):  
Rain Forest ◽  
Diversity Index ◽  
Anthropogenic Activities ◽  
Diversity Indices ◽  
Cross River ◽  
Montane Rain Forest ◽  
Cross River State ◽  
Individual Bird ◽  
Nesting Sites ◽  
Characteristic Features

This study assessed the abundance and nesting sites characteristics of red-headed picathartes (Picathartes oreas) in protected and unprotected forest in Cross River State, from August 2016 to January 2017. Data were collected through oral interviews, and field observations, using area search and quadrant methods. Data on bird and nest were tested using one-way ANOVA and t-test while tree species diversity indices were calculated using Paleontological Statistics Software Package, version 16. Results revealed that a mean of 38±52 individual bird from six colonies were sighted during the survey. Higher number of 20 (52.63%) individuals from two colonies was recorded in the undisturbed montane rain forest of the Okwangwo Division of the Cross River National Park than the disturbed montane rain forest with 18 (47.37%) individuals from four colonies. A total of 40 (50%; n = 20 each) nests of red-headed picathartes were sighted during the survey around the undisturbed and disturbed montane rain forest respectively. All (100%; n = 40) the nests observed were attached to the south-eastern side of the rocks and all the nests were constructed with mud mixed with grass. Colony Six was on the highest altitude with an elevation of 529 m, followed by colony two with an elevation of 342 m while the lowest elevation was 195 m recorded in colony three. Tree diversity index was higher in the protected forest (3.352; 3.227) than in the unprotected forest (1.846). Characteristic features of Picathartes oreas habitat were rock, hill, valleys and rivers and streams. It was evidenced by the study that Picathartes oreas still nests both in the disturbed and undisturbed forest but the level of disturbance and type of crops grown may have impact on the nesting behaviour. Therefore, anthropogenic activities should be regulated in the area, to ensure the conservation of Picathartes oreas. Keywords: Picathartes oreas; abundance; nesting sites characteristics; unprotected and protected forest.

scholarly journals Assessing landscape changes of catchment area of Upper Lake Bhopal using patch analysis

2014 ◽  
Vol 2 (7) ◽  
pp. 96-101
Author(s):  
Ajit Kumar Jain ◽  
S. K Katiyar ◽  
M. S Chauhan
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Catchment Area ◽  
Temporal Dynamics ◽  
Diversity Index ◽  
Wetland Management ◽  
Anthropogenic Activities ◽  
Shape Index ◽  
Diversity Indices ◽  
Barren Land

Anthropogenic activities impart serious challenges on wetland management. The issues of Anthropogenic Activities manifest in the form of environmental degradation, point and non-point source pollution of lake water. Catchment area of upper lake Bhopal has been witnessing the same scenario; raising the question of its planning and management to control water pollution. It shows the necessity to analyse and study the pattern of land use & land cover(LULC). In order to assess the LULC pattern and spatio-temporal dynamics the changing pattern of patch number(NP), class area(CA), mean patch size(MPS), mean shape index (MSI), Shannon’s Diversity index(SHDI), Simpson’s Diversity Index(SDI) of all land use/land cover categories. In this researchpaper above mentioned parameters were measured and analyzed for landuse/landcover change from year 2003 to 2011. Area of agriculture and built up land expanded 16.18% and 4.77% while number of patches reduced by 332 and 187 for these two classes respectively. On the other hand class area of vegetation and barren land reduced 9.33% and 11.62%. Few patches of vegetation completely eliminated resulted in reduction of number of patches by 1250. Increased no. of patches of barren land by 150 shows fragmentation. Reduction in diversity indices indicates that area becomes less diversified during study period. During the period of 2003 to 2011 shape of patches of agriculture and built up land becomes more complex and that of barren land and vegetation converted to simpler shape. These indices provided meaningful insights pertaining to the spatiotemporal dynamics prevailing in the catchment area of Upper Lake Bhopal.

Carabidae of Barnaul city parks: ecological characteristics and species composition

2018 ◽  
Vol 8 (2) ◽  
pp. 348-353
Author(s):  
E. A. Kuchina ◽  
N. D. Ovcharenko ◽  
L. D. Vasileva
Keyword(s):  
Species Composition ◽  
Diversity Index ◽  
Similarity Index ◽  
Life Forms ◽  
Ground Beetles ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Dominant Group ◽  
Species Diversity Index ◽  
Steppe Species

<p>Anthropogenic impact on the population of ground beetles leads to a change in their numbers, structure of dominance, density, species composition, spectrum of life forms. This makes the beetles Carabidae a convenient and informative bioindicator of the ecological state of biocenoses. The material for this work was the Carabidae collections conducted in June-August 2016-2017 in the park zone of different regions of Barnaul, differing in location, area, hydrological regime, vegetation cover, purpose and anthropogenic load. When processing the material, the quantitative, species and generic composition of the carabidae was determined, calculations were made for such indicators as the Berger-Parker dominance index, the Shannon species diversity index (Hs), and the Jacquard species similarity index. The fauna (Coleoptera, Carabidae) of the park zone of Barnaul is represented by 55 species belonging to 20 genera. The dominant group is represented by species belonging to steppe, forest and polyzonal groups. Forest-steppe species of ground beetles as dominants have not been identified in any of the investigated territories. The greatest variety of ecological groups was noted on the territory of the Yubileyny рark, which is explained by the presence of zones with various microclimatic conditions, the presence of a birch grove that flows through the park with the Pivovarka River, and a wide log in the park. Registered species belong to eight groups of life forms belonging to two classes - zoophagous and myxophytophagous. On the numerical and species abundance, zoophages predominate. The spectrum of life forms corresponds to the zonal spectrum characteristic of the forest-steppe zone.</p><p> </p>

scholarly journals Responses and Indicators of Composition, Diversity, and Productivity of Plant Communities at Different Levels of Disturbance in a Wetland Ecosystem

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 252
Author(s):  
Tingting Duan ◽  
Jing Zhang ◽  
Zhengjun Wang
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Leisure Activity ◽  
Local Environment ◽  
Diversity Indices ◽  
Soil Parameters ◽  
Grazing Tolerance ◽  
Organic Matter Concentration ◽  
Drought Tolerant ◽  
Different Levels

Grassland tourism is a very popular leisure activity in many parts of the world. However, the presence of people in these areas causes disturbance to the local environment and grassland resources. This study analyzes the composition, diversity, and productivity under different levels of disturbance of the plant communities in the Kangxi Grassland Tourist Area and the Yeyahu Wetland Nature Reserve of Beijing, China. It aims to identify indicators of plant communities and their responses to different levels of disturbance. Our analysis shows that the plant community density and coverage have a certain compensatory increase under disturbed conditions. With the increase in disturbances, more drought-tolerant species have appeared (increased by 5.7%), some of which have become the grazing-tolerance indicator species in the trampled grazed area (TGA). For plant community productivity, biomass and height are good indicators for distinguishing different disturbances (p < 0.05). In addition, several diversity indices reveal the change of plant communities from different perspectives (three of the four indices were significant at the p < 0.05 level). For soil parameters, soil water content and organic matter concentration help to indicate different disturbance levels (the former has a 64% change). Moreover, the standard deviation of the plant community and soil parameters is also a good indicator of their spatial variability and disturbance levels, especially for the TGA. Our analysis confirms that the indicators of productivity, diversity, and soil parameters can indicate the disturbance level in each subarea from different perspectives. However, under disturbed conditions, a comprehensive analysis of these indicators is needed before we can accurately understand the state of health of the plant community.

scholarly journals On a Variational Definition for the Jensen-Shannon Symmetrization of Distances Based on the Information Radius

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 464
Author(s):  
Frank Nielsen
Keyword(s):  
Diversity Index ◽  
Diversity Indices ◽  
Shannon Diversity Index ◽  
Probability Measures ◽  
Variational Optimization ◽  
Shannon Diversity ◽  
Concept Of Information ◽  
Jensen Shannon Divergence

We generalize the Jensen-Shannon divergence and the Jensen-Shannon diversity index by considering a variational definition with respect to a generic mean, thereby extending the notion of Sibson’s information radius. The variational definition applies to any arbitrary distance and yields a new way to define a Jensen-Shannon symmetrization of distances. When the variational optimization is further constrained to belong to prescribed families of probability measures, we get relative Jensen-Shannon divergences and their equivalent Jensen-Shannon symmetrizations of distances that generalize the concept of information projections. Finally, we touch upon applications of these variational Jensen-Shannon divergences and diversity indices to clustering and quantization tasks of probability measures, including statistical mixtures.

scholarly journals Testing the potential of pollen assemblages to capture composition, diversity and ecological gradients of surrounding vegetation in two biogeographical regions of southeastern Europe

2021 ◽  
Author(s):  
Maria Papadopoulou ◽  
Ioannis Tsiripidis ◽  
Sampson Panajiotidis ◽  
Georgios Fotiadis ◽  
Daniel Veres ◽  
...  
Keyword(s):  
Vegetation Structure ◽  
Diversity Indices ◽  
Life Forms ◽  
Ecological Gradients ◽  
Vegetation Diversity ◽  
North Central ◽  
Plant Life Forms ◽  
Pollen Diagrams ◽  
Biogeographical Regions ◽  
Species Specific

AbstractDue to the complex relationship between pollen and vegetation, it is not yet clear how pollen diagrams may be interpreted with respect to changes in floristic diversity and only a few studies have hitherto investigated this problem. We compare pollen assemblages from moss samples in two southeastern European forests with the surrounding vegetation to investigate (a) their compositional similarity, (b) the association between their diversity characteristics in both terms of richness and evenness, and (c) the correspondence of the main ecological gradients that can be revealed by them. Two biogeographical regions with different vegetation characteristics, the Pieria mountains (north central Greece) and the slopes of Ciomadul volcano (eastern Romania), were chosen as divergent examples of floristic regions, vegetation structure and landscape openness. Pollen assemblages are efficient in capturing the presence or absence, rather than the abundance in distribution of plants in the surrounding area and this bias increases along with landscape openness and vegetation diversity, which is higher in the Pieria mountains. Pollen assemblages and vegetation correlate better in terms of richness, that is, low order diversity indices. Relatively high correlation, in terms of evenness, could be potentially found in homogenous and species poor ecosystems as for Ciomadul. Composition and diversity of woody, rather than herb, vegetation is better reflected in pollen assemblages of both areas, especially for Pieria where a direct comparison of the two components was feasible, although this depends on the species-specific pollen production and dispersal, the openness of landscape and the overall diversity of vegetation. Gradients revealed by pollen assemblages are highly and significantly correlated with those existing in vegetation. Pollen assemblages may represent the vegetation well in terms of composition, diversity (mainly richness) and ecological gradients, but this potential depends on land use, vegetation structure, biogeographical factors and plant life forms.

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