scholarly journals Diversity and Species Composition of Subaerial Algal Communities in Forested Areas of Meghalaya, India

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Diana Kharkongor ◽  
Papiya Ramanujam

The study deals with a comparative study on diversity and species composition of subaerial algal communities from tree barks of closed undisturbed sacred grove, mixed plantation, and open disturbed forest. A total of 85 taxa had been recorded, 30 cyanobacteria and 55 algal species belonging to six classes of algae. Sacred grove harboured the highest subaerial algal diversity compared to those of plantation and open disturbed forest. There was a strong significant difference in species composition among the three different sampling areas. High number of diatoms with 14 species was recorded in sacred grove. Cyanobacteria with 22 species were the frequent group in disturbed forest whereas Trentepohliales dominated in plantation. Canonical correspondence analysis confirmed that high photon irradiance favored the growth of cyanobacteria in disturbed forest. The abundance of Trentepohliales members correlated to high rainfall and photon irradiance. High diversity and presence of many diatom species in undisturbed Mawphlang sacred grove were associated with low photon irradiance and high relative humidity and could also be due to a presence of suitable substrata formed by the growth of mosses. Sunlight, relative humidity, and rainfall were the important factors which played a major role in determining the diversity and distribution of subaerial algal communities.

2010 ◽  
Vol 45 (3) ◽  
pp. 374-378
Author(s):  
Hiroshi Kawai ◽  
Takeaki Hanyuda ◽  
Hideo Okamura ◽  
Masanobu Kawachi ◽  
Masayuki Kunugi ◽  
...  

SIMBIOSA ◽  
2014 ◽  
Vol 3 (2) ◽  
Author(s):  
Notowinarto Notowinarto ◽  
Ramses Ramses ◽  
Mulhairi Mulhairi

Bulang districts Batam Islands of  Riau province (Riau Islands), its consists of many islands with as well as having the potential diversity of coastal marine life in particular kinds of macro algae or seaweed. Conducted research aimed to determine the structure of macro- algal communities in the intertidal zone islands. The results of the identification of algal species found 16 species are: the Order of Chlorophyceae as 6 spesies; Order Phaeophyceae as 2 spesies; and Order Rhodophyceae as 8 spesies. The community structure at the five stations showed the highest values were found in the island of dominance Cicir (D ' = 0.79) , uniformity index values on Tengah Island (E ' = 0.99) , while the island Balak had the highest diversity index (H ' = 0.88) , with the abundance patterns of population structure on the island is pretty good Central . Results of correlation analysis of regression between IVI types of algae with the conditions of environmental quality suggests that there is a significance (Fhit ˃ F table and the value of r = > 90 %) between IVI algae Halimeda sp and Cryptarachne polyglandulosa at each station with a temperature parameter surface (⁰C) , depth temperature (⁰C) and pH values. Keywords : Algae, Community Structure, Important Value Index.


Author(s):  
Maame Esi Hammond ◽  
Radek Pokorný ◽  
Daniel Okae-Anti ◽  
Augustine Gyedu ◽  
Irene Otwuwa Obeng

AbstractThe positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of disturbance. This study evaluates the composition, diversity, regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed, intermittently disturbed, and disturbed forest sites. Bia Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site categories. Ten circular subsampling areas of 1 m2 were delineated at 2 m spacing along north, south, east, and west transects within individual gaps. Data on natural regeneration < 350 cm height were gathered. The results show that the intensity of disturbance was disproportional to gap size. Species diversity differed significantly between undisturbed and disturbed sites and, also between intermittently disturbed and disturbed sites for Simpson’s (1-D), Equitability (J), and Berger–Parker (B–P) indices. However, there was no significant difference among forest sites for Shannon diversity (H) and Margalef richness (MI) indices. Tree species composition on the sites differed. Regeneration density on the disturbed site was significantly higher than on the two other sites. Greater abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent pioneers. Pioneer species giving way to shade tolerant species is a natural process, thus make them worst variant in gap regeneration.


Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 256
Author(s):  
Petro M. Tsarenko ◽  
Olena P. Bilous ◽  
Olha M. Kryvosheia-Zakharova ◽  
Halyna H. Lilitska ◽  
Sophia Barinova

The species diversity and changes in the structural dynamics of the algal flora from the alpine lake Nesamovyte has been studied for 100 years. During the period of investigations, 234 species (245 infraspecific taxa) were revealed to cover more than 70% of the modern species composition of the studied lake. The modern biodiversity of algae is characterized by an increase in the number of widespread forms, a change from the baseline “montane” complex in comparison to the beginning of the 20th century. Nevertheless, the Nesamovyte Lake still has a unique algae composition that is typical for high-mountainous European lakes. The presence of a different complex of conventionally arctic species of algae, in particular, diatoms is discussed. Structural changes in the taxonomic composition of the algal flora of the lake as well as in the complex of the leading genera, species and their diversity are revealed. An ecological analysis of the algal species composition of the lake showed vulnerability and degradation to the ecosystem of the lake. On this basis, the issue regarding the question of protection and preservation of the algae significance and uniqueness of the flora of algae in the Nesamovyte Lake are discussed.


2020 ◽  
pp. 1-10
Author(s):  
C.A. Ngonga ◽  
C.O. Gor ◽  
E.A. Okuto ◽  
M.A. Ayieko

Cricket farming is emerging as a new venture in Kenya poised to help alleviate protein deficiency and improve household living standards. However, competing, limited and unaffordable rearing systems constrain productivity and optimisation of this new enterprise. This study sought to evaluate the growth performance of Acheta domesticus and Gryllus bimaculatus reared in improvised cage system to assess its technical effectiveness. Twenty-day old of both species of crickets were separately reared in improvised and conventional cage systems for comparison purposes. Whereas an improvised cage system is a set of structure devised using locally available materials especially where the standard materials are limited, a conventional cage system is a set of structure made of standard and ordinary materials. The improvised system comprised of bamboo hideouts, clean scrap blankets for drinking and laying, cut bamboo stem as drinking platter and the plywood-based cages while conventional system comprised of egg carton hideouts, cotton-wool for drinking and laying, plastic petri-dishes, and plastic buckets. Each group of crickets (100 live crickets) was daily provided with equal amount of feed and water. Average weekly temperature and relative humidity profiles were recorded using HOBO data loggers. Further, 49 live crickets per treatment were randomly sampled and weighed weekly. Generalised additive model and analysis of variance were adopted to model the data therefrom using R. The cage system had a significant effect on the growth performance of the crickets. The mean weight of the cricket species differed, but not the interaction with the cage system. Similarly, species, temperature and relative humidity also influenced the growth performance. Compared to the conventional system, improvised cage system showed better results in realising high cricket productivity though there was no significant difference in growth performance between the two systems. The focus therefore should be to evaluate the egg productivity in scrap blanket in relation to cotton wool and cost effectiveness in improvised system to inform future farm decisions.


1970 ◽  
Vol 17 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Anita Pokharel ◽  
Madhu Chhetri ◽  
Chiranjibi P Upadhyaya

Limited information is available on the species composition, above ground biomass and its relations to grazing in a trans-Himalayan rangeland. Its assessment is essential for long term conservation and management. In the present study, we compared species composition, phenology, diversity index and biomass between controlled (without grazing) and open (free grazing) plots to assess the effects of grazing in the selected experimental sites of Upper Mustang during July and November 2005. Species encountered were classified as high, medium, low and non palatable and in three life form categories-grasses, shrubs and forbs. The experimental sites are dominated by forbs (80%) followed by grasses (15%) and shrubs (5%). Disturbance caused by grazing affects the phenological characteristics of the plant community. Result also reveals that species diversity, maximum possible diversity, evenness and species richness was higher in the grazed plots during July and November. A comparison of the aboveground biomass in July showed that mean percentage biomass of high, medium and low palatable species is higher in ungrazed plots. In November, the percentage biomass of only medium palatable species was higher in ungrazed plots and rest of the category is higher in grazed plots. Significant difference in July, a peak growing seasons for most of the plant species in the region reveals that the pasture has impact of livestock grazing. Keywords: Biomass, diversity, grazing effect, rangeland, species Banko Janakari: A journal of forestry information for Nepal Vol.17(1) 2007 pp.25-31


2017 ◽  
Vol 2 (2) ◽  
pp. 41-48
Author(s):  
E. P. Karpova ◽  
A. R. Boltachev ◽  
O. N. Danylyuk

Cryptobenthic fauna investigations are highly relevant at studying biodiversity of regions. Studies of the species composition of Gobiesocidae family were carried out in order to clarify ichthyofauna of different regions, and a new species for the Black Sea coastal zone of Crimea was found. Information about its morphology, biology, behavior and other characteristics is very important because of weak study and indeterminate taxonomic status of this species. As a result of morphological studies of the Crimean specimens no significant difference with the type of the Atlantic-Mediterranean populations has been proven. Naturalization of small-headed clingfish in coastal waters of Crimea has been confirmed and some population characteristics, such as a length-weight relationship, have been described. Peculiarities of habitat which which small-headed clingfish prefers and features of localization, enabling competitiveness have been identified. Identification keys were compiled and are given in the paper.


Irriga ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 52 ◽  
Author(s):  
Vinícios Maia Costa ◽  
Marcos Vinícios Folegatti ◽  
Roberto Terumi Atarassi ◽  
Sérgio Nascimento Duarte ◽  
Nildo Da Silva Dias ◽  
...  

DESENVOLVIMENTO DE MUDAS DE CAFEEIRO PRODUZIDAS EM TUBETES SOB MALHAS TERMO-REFLETORAS E MALHA NEGRA VINÍCIUS MAIA COSTA1; MARCOS VINÍCIUS FOLEGATTI2; ROBERTO TERUMI ATARASSI3; SÉRGIO NASCIMENTO DUARTE4; NILDO DA SILVA DIAS5 E CLAUDIO RICARDO DA SILVA6.  [1] Mestre em Agronomia, Depto. de Engenharia de Biossistemas, ESALQ-USP, Piracicaba – SP. E-mail: [email protected]. Titular, Depto. de Engenharia de Biossistemas, ESALQ-USP, Piracicaba – SP. E-mail: [email protected] de Ciências Agrárias, UFU, Av. Amazonas, s/n, Bloco 2E, Campus Umuarama, 38400-902, Uberlândia-MG. E-mail: [email protected]. Associado, Depto. de Engenharia de Biossistemas, ESALQ-USP, Piracicaba – SP. E-mail: [email protected] Associado 2, Departamento de Ciências Ambientais e Tecnológicas, Universidade Federal Rural do Semi-Árido, Mossoró, RN. E-mail: [email protected] de Ciências Agrárias, UFU, Av. Amazonas, s/n, Bloco 2E, Campus Umuarama, 38400-902, Uberlândia-MG. E-mail: [email protected].  1 RESUMO Este experimento avaliou, em casa de vegetação, o desenvolvimento de mudas de cafeeiro produzidas em tubetes, sob o efeito de malhas utilizadas para sombreamento. Os tratamentos foram a tradicional malha negra 50% e as malhas termo-refletoras com atenuação da radiação solar de 40, 50, 60 e 70%. O delineamento experimental adotado foi em blocos casualizados contendo os 5 tratamentos, com 4 repetições, totalizando-se assim 20 parcelas. Os resultados mostram que temperatura do ar pouco variou no microclima protegido das parcelas, assim como a umidade relativa do ar e a transmissividade global (TRG) e fotossinteticamente ativa (TRFA). Verificou-se que malhas com menor atenuação da radiação solar apresentaram em geral maior transmissividade. A área foliar não apresentou diferença significativa entre os tratamentos; já para altura da planta e diâmetro do caule, verificou-se que as mudas produzidas sob as malhas termo-refletoras 40 e 50% foram superiores àquelas produzidas sob malha negra 50% e malhas termo-refletoras 60 e 70%, respectivamente. Nas avaliações de matéria seca, verificou-se que as mudas produzidas sob as malhas termo-refletoras 40% e 50% e malha negra 50% acumularam mais matéria seca comparativamente àquelas produzidas sob malhas termo-refletoras 60 e 70%. Assim, concluiu-se que as malhas termo-refletoras 40 e 50% e negra 50% apresentaram melhores resultados que as malhas termo-refletoras 60 e 70%. Palavras-chave: Coffea arábica L., sombreamento, ambiente protegido.  COSTA, V.M.; FOLEGATTI, M.V.; ATARASSI, R.T.; DUARTE, S.N.; DIAS, N.S.; SILVA, C.R. DEVELOPMENT OF COFFEE SEEDLINGS PRODUCED IN PLASTIC TUBESUNDER TERMO-REFLECTIVE AND BLACK SCREENS   2 ABSTRACT This experiment evaluated, in greenhouse conditions, the development of coffee seedlings produced in plastic tubes, under the effect of screens used for shading. The treatments were the traditional black screen 50% and the thermo reflective screens with attenuation of the solar radiation of 40, 50, 60 and 70%. The adopted experimental delineation was randomized blocks with 5 treatments and 4 replicates, making up 20 parcels. The result showed that the temperature of air gently varied in the parcels, as well as the air relative humidity.  Relating to global transmissivity (TRG) and photosynthetically active transmissivity (TRFA), it was verified that screens with less attenuation of the solar radiation presented higher transmissivity in general. The leaf area did not present significant difference among the treatments and seedlings height and stalk diameter, the seedlings produced under thermo-reflective screens 40% and 50% were superior to those produced under black screen 50% and thermo-reflective screen 60% and 70%. In the evaluations of dry matter, the seedlings produced under thermo-reflective screens 40% and 50%, and black screen 50% comparatively accumulated more dry matter than those produced under thermo-reflective screens 60% and 70%. Thus, it can be concluded that the thermo-reflective screens 40% and 50% and black screen 50% presented better results than the thermo-reflective screens 60% and 70%. Keywords: Coffea arábica L., shading, greenhouse.


2020 ◽  
Vol 12 (16) ◽  
pp. 2631
Author(s):  
Marian Amoakowaah Osei ◽  
Leonard Kofitse Amekudzi ◽  
Craig R. Ferguson ◽  
Sylvester Kojo Danuor

The vertical profiles of temperature and water vapour from the Atmospheric InfraRed Sounder (AIRS) have been validated across various regions of the globe as an effort to provide a substitute for radiosonde observations. However, there is a paucity of inter-comparisons over West Africa where local convective processes dominate and radiosonde observations (RAOBs) are limited. This study validates AIRS temperature and relative humidity profiles for selected radiosonde stations in West Africa. Radiosonde data were obtained from the AMMA and DACCIWA campaigns which spanned 2006–2008 and June–July 2016 respectively and offered a period of prolonged radiosonde observations in West Africa. AIRS performance was evaluated with the bias and root mean square difference (RMSD) at seven RAOB stations which were grouped into coastal and inland. Evaluation was performed on diurnal and seasonal timescales, cloud screening conditions and derived thunderstorm instability indices. At all timescales, the temperature RMSD was higher than the AIRS accuracy mission goal of ±1 K. Relative humidity RMSD was satisfactory with deviations <20% and <50% for both lower and upper troposphere respectively. AIRS retrieval of water vapour under cloudy and cloud-free conditions had no significant difference whereas cloud-free temperature was found to be more accurate. The seasonal evolution of some thunderstorm convective indices were also found to be comparable for AIRS and RAOB. The ability of AIRS to capture the evolution of these indices imply it will be a useful dataset for the African Science for Weather Information and Forecasting Techniques (SWIFT) high impact weather studies.


2015 ◽  
Vol 63 (4) ◽  
pp. 353
Author(s):  
A. El Ghalabzouri ◽  
R. Ajbilou ◽  
M. G. Mariotti ◽  
K. Targuisti ◽  
M. Ater

Vegetation and soil sampling were undertaken in 47 relevés in two different sites in Beni Bousera (northern Morocco), 32 relevés were on ultramafic sites (peridotite) and 15 were on adjacent non-ultramafic soils (mica-schist). Soil composition of exchangeable elements (nickel, calcium, magnesium, calcium : magnesium ratio, iron, copper) and physicochemical characteristics (e.g. pH, cation exchange capacity, conductivity, carbonate) were investigated and the species composition and cover were recorded. Although there was a significant difference between the two types of soil shown by Student’s t-test and principal component analysis, the ‘serpentine factor’ can be considered moderate on the basis of the observed heavy metal concentrations and of the related calcium : magnesium ratio. Correspondence and canonical analysis were used to detect the principal factors associated with gradients in species composition. This analysis showed a clear differentiation of vegetation among the plant communities. Preferential or strict serpentinophyte species were recognised, whereas no hyperaccumulator species have yet been found.


Sign in / Sign up

Export Citation Format

Share Document