diversity index
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2023 ◽  
Vol 83 ◽  
Author(s):  
H. Ul-Hassan ◽  
S. Mahboob ◽  
Z. Masood ◽  
M. N. Riaz ◽  
S. Rizwan ◽  
...  

Abstract This study was conducted to estimate the diversity and the occurrence of commercially important finfish species collected by twenty fish sampling site of Sindh and Baluchistan coasts of the Arabian Sea in Pakistan from January to December 2019. Additionally, physicochemical characteristics of seawater were analyzed from these selected sites and found to be within suitable ranges required for fish growth and survive. A total of 81287 fish individuals were collected and identified as 49 species belonging to 26 families in our study. The most diversified family was Sparidae (13 species) followed by Carangidae and Lutjanidae (4 species), Mullidae, Serranidae, Ariidae (3 species), and Sciaenidae (2 species). The remaining 20 families were represented by only one species. The values of Shannon diversity index calculated for the four selected habitats revealed that high fish diversity was reported at Sonmiani Coast (H'=1.81), while less at Ormara Coast (H'=0.23). Likewise, Evenness index (E) was high at Sonmiani Coast (E=0.50) and less fish diversity was reported at Ormara Coast (E=0.06). Reducing risks to threatened marine species in coastal habitats also requires conservation actions at multiple scales. Thus, it was concluded that our study could be valuable in providing the more information’s regarding to the diversity of finfish species and their occurrence along the Pakistan Coast. Further, to better understand the effects, regular monitoring and conservation measures should be taken to mitigate the influence of anthropogenic activities and protect finfish diversity from further decline


2023 ◽  
Vol 83 ◽  
Author(s):  
M. Attaullah ◽  
I. Ullah ◽  
M. Ali ◽  
F. Maula ◽  
I. Ilahi ◽  
...  

Abstract Odonates are important biological control agents for the control of insect pests and insect disease vectors of medical and veterinary importance. The present study was conducted to evaluate the odonate fauna of Swat, Pakistan from March to October 2019. A total of 200 specimens of odonates were collected from diverse habitats. The collected specimens of the order Odonata belonged to 5 families, three families of suborder Anisoptera namely Libellulidae, Gomphidae and Aeshnidae while two families of suborder Zygoptera (Chlorocyphidae and Coenagrionidae). The specimens were categorized into 12 genera and 22 species. Libellulidae was the dominant family (n = 138) accounting for 69% of the odonate fauna. Orthetrum was the dominant genus (n = 73) of suborder Anisoptera accounting for 36.5% of the odonate fauna. The least dominant genera were Anax, Paragomphus and Rhyothemis (n = 5 each) accounting each for 2.5% of the odonate fauna. In Zygoptera, the dominant genus was Ceriagrion (12.5%) and the least dominant genus was Ischnura (6%). Pantala flavescens (Fabricius, 1798) was the most abundant odonate species in the study area recorded from all surveyed habitats. Shannon Diversity Index (H) was 2.988 and Simpson Diversity Index (D) was 0.95 for the collected odonate fauna. The highest abundance of Odonata was recorded in August, September and May while no odonate species were recorded in January, February, November and December. Lotic water bodies were the most suitable habitats with abundant odonate fauna. Anax immaculifrons (Rambur, 1842) was the largest sized odonate species having a wingspan of 53.2±1.63 mm and body length of 56.3 ± 0.4 mm. The present study shows the status of odonate fauna of Swat, Pakistan in diverse habitats and seasonsonal variation throughout the year. Further work is recommended to bridge the gaps in the existing literature.


Author(s):  
Amanda Queiroz Bastos ◽  
Cecilia Ferreira de Mello ◽  
Júlia dos Santos Silva ◽  
Hélcio Reinaldo Gil-Santana ◽  
Shayenne Olsson Freitas Silva ◽  
...  

Abstract This study registers the diversity of Culicidae in the Bom Retiro Private Natural Heritage Reserve (RPPNBR), Rio de Janeiro state, Brazil, based on the collection of the immature stages in natural and artificial larval habitats. Larvae and pupae were collected monthly at two sites of the RPPNBR from May 2014 to July 2015 using dippers and aquatic pipettes. The diversity of the mosquito community was described using the Shannon–Wiener Diversity Index (H′), as well as diversity, richness, and dominance of species found in different larval habitats (lake, bamboos, bromeliads, and artificial vessels). The Mann–Whitney test was used to calculate differences between the two natural and artificial habitats. Overall, 15,659 specimens belonging to 25 species, ten genera, and two subfamilies were collected. The most abundant species collected at sites that were reforested recently were Culex pleuristriatus Theobald, 1903, Limatus durhamii (Theobald, 1901), Aedes albopictus (Skuse, 1895), Culex neglectus (Lutz, 1904), and Culex retrosus (Lane & Whitman, 1951). In a forest preserved site, the most abundant species were Cx. neglectus, Culex iridescens (Lutz, 1905), Sabethes identicus (Dyar & Knab, 1907), Wyeomyia arthrostigma (Lutz, 1905), and Li. durhamii. With respect to larval habitats, 0.1% of the specimens were collected along the edge of a lake, 5.5% in bamboos, 35.9% in bromeliads, and 58.4% in artificial containers. Only 5.5% of the specimens were collected in the forest preserved site, with the remaining samples from the site with altered vegetation. A greater species richness and diversity were found in forest-altered sites compared to the forest preserved site. Several species were collected in the water accumulated in the nylon lids of plastic water tanks. Such vessels can promote an increase in mosquito population density in the environment surrounding the study area.


2022 ◽  
Vol 14 (2) ◽  
pp. 353
Author(s):  
Mengying Ruan ◽  
Zhenqi Hu ◽  
Xinyi Duan ◽  
Tao Zhou ◽  
Xinran Nie

Coal gangue is an inevitable product in coal mining and processing and is the most important source of pollution in mines. Vegetation restoration of coal gangue piles must consider its special site conditions. Therefore, we conducted unmanned air vehicle (UAV) temperature monitoring, field investigation and experimental analysis on spontaneous combustion coal gangue piles in Lu’an mining area. In the vegetation construction of coal gangue piles, high-temperature stress affects plant survival. The spontaneous combustion coal gangue piles have abnormal temperature, high surface temperature and few vegetation types. The plant community species diversity index (Shannon–Wiener index, Pielou’s index and Species abundance index) is small, the plant community is single and the plant diversity is low. Spontaneous combustion of coal gangue leads to soil acidification, reducing soil water content, soil organic carbon (SOM), available nitrogen (AN), available potassium (AK) and available phosphorus (AP). These factors are single or interactive in plants and have an impact on plant survival and growth. The research results are of great significance to the vegetation restoration of spontaneous combustion coal gangue piles, ecological reconstruction and the improvement of the ecological environment of coal mine areas.


2022 ◽  
Author(s):  
Sagheer Atta

Citrus is a valuable crop in Pakistan because it is rich in vitamin C and antioxidants. Huanglongbing (HLB) has an influence on citrus production around the world caused by a bacterium “ Candidatus   liberibacter asiaticus ” (CLas), africanus and americanus. The structure and diversity of bacterial species in various ecosystems can be quickly examined using NGS. This approach is considerably quicker and more precise than outdated methods. Healthy or citrus greening infected leaf samples of Grapefruit,  Citrus aurantifolia , and  Citrus reticulata  Blanco was used for diversity analysis. In this study high throughput, NGS technique was used to access the population of both cultivable and non-cultivable bacterial endophytes from citrus leaves, by using PCR amplicons of 16S rDNA sequences (V5–V7 regions) with Illumina Hi seq. As a result, a total number of 68,722 sequences were produced from the test samples. According to the NGS-based diversity classification, the most common genera of exploited bacterial endophytes were Proteobacteria, Firmicutes, Bacteroides, Cyanobacteria, and Actinobacteria.  Citrus aurantifolia  and  Citrus paradisi  showed almost equal diversity, whereas  Citrus reticulata  Blanco had a higher proportion of Proteobacteria and Cyanobacteria in their leaves. To determine alpha diversity (AD), additional data was analyzed using statistical indices such as Shannon, Chao1, and Simpson. According to the inverse Simpson diversity index, the abundance of the microbial population in six different citrus samples was 0.48, 0.567, and 0.163, respectively. The metagenomics of microbiota in plant tissues was successfully recorded by NGS technology, which can help us learn more about the interactions between plants and microbes. This research is the first step toward a better understanding of 16SrRNA-based metagenomics from citrus in Pakistan using Illumina (Hi seq) Technology.


2022 ◽  
Vol 14 (2) ◽  
pp. 887
Author(s):  
Ishfaq Ahmad Wani ◽  
Susheel Verma ◽  
Renu Gupta ◽  
Masood Majaz Ganaie ◽  
Gaurav Nigam ◽  
...  

The alpine grasslands of Kashmir Himalaya act as a treasure house of floristic biodiversity. They have remained largely unstudied because of their remoteness and inaccessibility. It is imperative to have quantitative studies of these areas to allow the long-term monitoring of flora in these fragile ecosystems. During the present study, nutrient analysis and species diversity of some alpine grasslands were investigated. Electroconductivity (EC) of the soils ranged between 0.12 and 0.33 (dSm−1). With an increase in altitude and precipitation and a decrease in temperature, soil pH and available macro-nutrients (OC, N, P, K) show a considerable decrease. Sixty-six plant species belonging to twenty-nine families and fifty-one genera were reported with members predominantly from the Asteraceae, Rosaceae and Plantaginaceae families. Seven species were common to all study areas and Renyi diversity profiles showed that Kongwattan was the most diverse followed by Poshpathri and Yousmarg. The results of the Sorensen β diversity index showed a relatively lower dissimilarity index among the three studied alpine sites. In the majority of the growth forms, growth initiation was recorded in April, whereas senescence occurred in September. The highest bloom was seen in June-July. The plant species exhibited a greater variability in their phenophases under different environmental conditions and altitudinal gradients. Plants were more vigorous at lower altitudes and showed rapid response to the prevailing conditions. Stoloniferous forbs and tussock forming graminoids such as Sibbaldia cuneata, Trifolium repens, Plantago major, Trifolium pratense, Poa compressa, Poa angustifolia, and Plantago lanceolata showed a greater importance value index (IVI). The sedentary system of livestock rearing at Yousmarg resulted in the decreased density of the palatable species. This study allowed us to conclude that direct knowledge of soil nutrient composition and species diversity in alpine ecosystems can enhance conservation and ensure better management practices over a period of time.


2022 ◽  
Vol 95 (1) ◽  
Author(s):  
Hussen Yasin ◽  
Wondimagegnehu Tekalign

Abstract Background Agroforestry is an integrated land-use system that plays a great role in the conservation of landscape biodiversity. The study aimed to assess the composition and diversity of avian species along with different habitat types of agroforestry in Kibet Town, Southern Ethiopia. Methods Four habitat types of agroforestry system which are home gardens, live fences, parkland, and eucalyptus woodlot were identified. Line transects were used for bird surveys. The Shannon diversity index (H′) and species evenness index (E) were used to compare diversity among habitat types. A similarity percentages (SIMPER) test was carried out to identify the main species and feeding guild that typified each habitat type. The overall significance was assessed with the ANOSIM test using PAST (version 4.03). Results A total of 50 bird species belonging to 28 families and 10 orders were recorded. Order Passeriformes (67.3%) had the highest number of species. Bird community composition differed among habitat types. The dissimilarity was mainly due to White-browed robin-chat (Cossypha heuglini), Streaky seed-eater (Serinus striolatus), Village Weaver (Ploceus cucullatus), African Paradise-Flycatcher (Terpsiphone viridis), and Black-Headed Paradise Flycatcher (T. rufiventer). The finding also revealed that insectivore was the dominant feeding guild. Conclusions The present study shows evidence that more insectivore bird species use different types of agroforestry as habitat and foraging sites. So, any concerned bodies who have engaged in avian conservation should give special consideration to this modified landscape.


2022 ◽  
Vol 14 (2) ◽  
pp. 314
Author(s):  
Pamela Ochungo ◽  
Nadia Khalaf ◽  
Stefania Merlo ◽  
Alemseged Beldados ◽  
Freda Nkirote M’Mbogori ◽  
...  

The region of Southern Ethiopia (Borana) and Northern Kenya (Marsabit) is characterised by erratic rainfall, limited surface water, aridity, and frequent droughts. An important adaptive response to these conditions, of uncertain antiquity, has been the hand-excavation of a sequence of deep wells at key locations often along seasonal riverbeds and valley bottoms where subterranean aquifers can be tapped. Sophisticated indigenous water management systems have developed to ensure equitable access to these critical water resources, and these are part of well-defined customary institutional leadership structures that govern the community giving rise to a distinctive form of biocultural heritage. These systems, and the wells themselves, are increasingly under threat, however, from climate change, demographic growth, and socio-economic development. To contribute to an assessment of the scale, distribution and intensity of these threats, this study aimed to evaluate the land-use land-cover (LULC) and precipitation changes in this semi-arid to arid landscape and their association with, and impact on, the preservation of traditional wells. Multitemporal Landsat 5, 7 and 8 satellite imagery covering the period 1990 to 2020, analysed at a temporal resolution of 10 years, was classified using supervised classification via the Random Forest machine learning method to extract the following classes: bare land, grassland, shrub land, open forest, closed forest, croplands, settlement and waterbodies. Change detection was then applied to identify and quantify changes through time and landscape degradation indices were generated using the Shannon Diversity Index fragmentation index within a 15 km buffer of each well cluster. The results indicated that land cover change was mostly driven by increasing anthropogenic changes with resultant reduction in natural land cover classes. Furthermore, increased fragmentation has occurred within most of the selected buffer distances of the well clusters. The main drivers of change that have directly or indirectly impacted land degradation and the preservation of indigenous water management systems were identified through an analysis of land cover changes in the last 30 years, supporting insights from previous focused group discussions with communities in Kenya and Ethiopia. Our approach showed that remote sensing methods can be used for the spatially explicit mapping of landscape structure around the wells, and ultimately towards assessment of the preservation status of the indigenous wells.


2022 ◽  
Vol 5 ◽  
Author(s):  
Adama Douyon ◽  
Omonlola Nadine Worou ◽  
Agathe Diama ◽  
Felix Badolo ◽  
Richard Kibarou Denou ◽  
...  

Many African countries, including Mali, depend on the production of a single or a limited range of crops for national food security. In Mali, this heavy reliance on a range of basic commodities or staple crops, or even just one, exacerbates multiple risks to agricultural production, rural livelihoods, and nutrition. With this in mind, the smart food campaign was initiated to strengthen the resilience and nutritional situation of households and peasant communities where the diet is mainly cereal-based and remains very undiversified and poor in essential micronutrients. As part of the campaign, our study aims to analyze the impact of agricultural diversification on food consumption and household nutritional security. The analysis uses survey data from 332 individuals randomly selected. Multinomial logistic regression and the Simpson diversity index were used to determine the index and estimate the determinants of crop diversification. The consumption score index weighted by consumption frequency and anthropometric indices (for children) were used to assess the nutritional status of households. The results show four types of strategies of diversification: 7.55% are cereals only, 5.66% combine millet–sorghum–groundnut, 41.51% combine millet–sorghum–groundnut–cowpea, and 45.28% combine millet–sorghum–groundnut–cowpea–maize. The estimation of the regression model shows that socioeconomic factors have a positive influence. With a consumption score index of 34 in the villages and 40.5 in Bamako, based on eight food groups, we find that the quality of food is insufficient in rural areas, but it is acceptable in the urban center of Bamako. Analysis of the nutritional status of children aged 6–48 months reveals that 30% of the surveyed population is in a situation of nutritional insecurity (all forms combined). To help improve crop diversification and the nutritional quality of foods, we suggest, among other things, subsidies and public spending to facilitate access to inputs that allow the acquisition of a wider range of inputs and services, intensification of nutrition awareness, and education programs to maximize the incentive to consume nutritious foods from self-production and market purchases. Finally, we propose to facilitate access to technologies promoting food diversification and improving food and nutritional security, particularly in rural areas.


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