scholarly journals Impact of Nitellopsis obtusa (Desv.) J. Groves, a regionally alien and invasive charophyte, on macrophyte diversity in the species native range

Hydrobiologia ◽  
2021 ◽  
Author(s):  
Mariusz Pełechaty ◽  
Bazargul Zhapparova ◽  
Michał Brzozowski ◽  
Andrzej Pukacz

AbstractThis study aimed to determine the relationships between the abundance of Nitellopsis obtusa, a controversial charophyte, locally red-listed in its native Eurasian range but invasive in North America, and the species diversity of macrophyte stands dominated by N. obtusa. Three lakes of different morphology, productivity and catchment were surveyed in the species native range. In each lake, the species composition and cover of three N. obtusa-dominated stands were determined monthly from spring to autumn and illustrated by the Shannon–Wiener diversity index. Water chemistry supplemented vegetation study. The species diversity turned out to be lake-specific and declined with the increasing share of N. obtusa, which developed mass occurrence in less mineralised and less fertile waters, leaving no space and limiting light and nutrient availability for large and branchy macrophytes. We postulate that this mechanism makes N. obtusa a superior competitor in less fertile waters and seems common to both native and invaded territories, as is the pool of macrophyte species most frequently co-occurring with N. obtusa.

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Hellen K. Mandela ◽  
Mugatsia H. Tsingalia ◽  
Mary Gikungu ◽  
Wilbur M. Lwande

Pollination is an important ecosystem service in the maintenance of biodiversity and most importantly in food production. Pollination is on the decline due to habitat loss, exotic species invasions, pollution, overharvesting, and land use changes. This study analyzed the abundance and diversity of flower visitors’ of Ocimum kilimandscharicum in Kakamega forest with increasing distance from the forest edge. Data were collected through direct observation and sweep netting. Six study sites were identified along two transects each 2.5 km long and labeled A to F. Distance in metres from the forest edge to each site was A=221, B=72, C=83, D=198, E=113, and F=50. Sampling was done from 7:30 am to 4:00 pm, three days in a week for five months consecutively. Diversity indices of different flower visitors were calculated using the Shannon-Wiener diversity index. One-way analysis of variance was used to compare differences between sites and a two-sample t-test was used to identify mean significant differences in species diversity between the closest and the furthest sites. A total of 645 individuals belonging to 35 species were captured from 4 families. The highest diversity was at site F (H’= 2.38) which was closest to the forest edge and the lowest diversity was from site A (H’=1.44) which was furthest from the forest edge. Distance from the forest edge significantly influenced species diversity (F(3, 20)=14.67, p=0.024). Distance from the forest edge also significantly influenced species abundance between the furthest sites A, D, and E and the nearest sites F, B, and C to the forest edge (t=4.177; p=0.0312) and species richness (t=3.2893; p=0.0187). This study clearly demonstrates that Ocimum kilimandscharicum flower visitors play essential roles in pollination and their higher number of visits translates into higher numbers of seeds set. Many of these pollinators are associated with the forest and hence the need to conserve the Kakamega forest as a source pool for pollinators.


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


2021 ◽  
Vol 267 ◽  
pp. 01035
Author(s):  
Ziqi Zhang ◽  
Lei Yang ◽  
Dongxu Han ◽  
Hongyan Shen

An investigation of phytoplankton community and water quality for M River was conducted in December 2019.The results showed that 38 species of phytoplankton belonging to 6 phyla and 26 genera were collected. Among them, Bacillariophyta is the richest species, which accounted for 34.21%, followed by Cyanophyta with 26.32% and Chlorophyta with 28.95%. The density of phytoplankton was 63.0*106 inds/L which indicated as eutrophic water body. The highest density was Bacillariophyta, accounting for 51.03%. The Shannon-Wiener diversity index (H’) varied from 1.34 to 2.24, the Margalef Species diversity index (d) varied from 2.71 to 3.85, and the Pielou evenness index (J) varied from 0.38 to 0.67. According to the integrative analysis results of H’, d and J, M River water quality belongs to oligo-polluted, but individual sites belong to meso-polluted.


2019 ◽  
Vol 11 (7) ◽  
pp. 1941 ◽  
Author(s):  
Yuzhe Li ◽  
Jiangwen Fan ◽  
Hailing Yu

Grasslands in northern China form an important ecological barrier that prevents and controls desertification. The Beijing–Tianjin Sand Source Control (BTSSC) Project has been implemented to restore grassland in order to control sand sourced pollution. This study aimed to understand the impacts of four applied restoration practices on the productivity, composition, and species diversity of vegetation communities in the BTSSC Project. The results indicated the following: (1) All the restoration practices tended to increase the height and cover of communities, and the effect was most obvious where grazing was excluded; (2) total biomass (87%), above-ground biomass (164%) and below-ground biomass (58%) only increased consistently when grazing was excluded from the steppe; (3) fenced and grazing exclusion practice significantly increased the abundance of species in communities, but all the practices tended to decrease the evenness of species; and, (4) the correlation analysis revealed that the Shannon–Wiener diversity index, and Pielou evenness index, showed significant negative correlations with the above-ground biomass of grassland communities after restoration, while no significant relationships were shown in reference plots. Our comparison of applied practices in the BTSSC project revealed that grazing exclusion might be a high priority for more successful restoration in this region.


2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Imam Widhiono ◽  
Eming Sudiana ◽  
Darsono Darsono

Increases in mean temperature affect the diversity and abundance of wild bees in agricultural ecosystems. Pollinator community composition is expected to change along an elevational gradient due to differences in the daily ambient temperature. This study investigated the diversity and abundance of wild bees in an agricultural area along an elevational gradient in Central Java, Indonesia. Wild bees were collected using a sweep net in 40 green bean (Phaseolus vulgaris) cultivation sampling locations at seven different elevations (8, 108, 224, 424, 644, 893, and 1017 m above sea level). Species diversity was determined using the Shannon–Wiener diversity index. We identified 932 individuals from 8 species of wild bee belonging to 3 families. The family Apidae was predominant, with 6 species, while only 1 species was found from each of Megachilidae and Halictidae. Across the study sites, diversity increased with increasing elevation (H′= 1.4,D= 0.25, andE= 0.78 at low elevation toH′= 2.04,D= 0.13, andE= 0.96 at high elevation), and higher numbers of species were found at middle and high elevations. Species richness and abundance increased linearly with increasing elevation, and species diversity was highest at middle elevations.


2021 ◽  
Vol 13 (7) ◽  
pp. 18827-18845
Author(s):  
Kismat Neupane ◽  
Mahamad Sayab Miya

A study was carried out to find the butterfly species diversity and abundance in Putalibazar Municipality, Syangja, Gandaki, Nepal, from June 2019 to July 2020. Pollard walk method was used for data collection in three different habitat types: forest, agricultural land, and settlement area. The study was performed in all seasons: pre-monsoon, monsoon, post monsoon and winter. A total of 180 butterfly species from 108 genera and six families were recorded. The overall Shannon-Wiener diversity index (H) was 4.48. The highest diversity was represented by the Nymphalidae with 67 species (H= 3.79). Butterfly diversity and species abundance was highest in the forest area (147 species, 1199 individuals; H= 4.47). The highest species richness (109 species) was observed in the monsoon season.


2020 ◽  
Vol 22 (1) ◽  
Author(s):  
Ida Ardiyaningrum ◽  
MARIA THERESIA SRI BUDIASTUTI ◽  
KOMARIAH KOMARIAH

Abstract. Ardiyaningrum I, Budiastuti MTS, Komariah. 2021. Short Communication: Species composition and diversity of vegetation in dryland agricultural landscape. Biodiversitas 22: 65-71. Drylands are a part of the terrestrial ecosystems with a relatively larger area compared to wetlands. Selo has dryland with steep slopes and high rainfall, resulting in relatively high soil erosion. The land use in this sub-district is dominated by plantations and agriculture, with conditions that have not been fully balanced by trees as a means of controlling erosion and supporting vegetation diversity. Therefore, studies on biodiversity are important as an indicator of dryland sustainability, especially in terms of soil and water conservations. This research aimed to study the species composition and diversity of vegetation in the dryland agricultural landscape in Selo Sub-district, Boyolali District, Central Java Province, Indonesia. Vegetation analysis was performed by using the quadratic sampling technique for tree category, pole category, sapling category, and seedling categories. The results indicated that Fabaceae had the highest number of species. Tree species with the highest Importance Value Index were Toona sureni, Artocarpus heterophyllus, and Casuarina junghuhniana, respectively. The Shanon-Wiener Diversity Index showed that the vegetation at tree, pole, and sapling stages had a moderate diversity, and seedling-stage vegetation had a low diversity.


Biosfera ◽  
2015 ◽  
Vol 32 (1) ◽  
pp. 1
Author(s):  
Donan Satria Yudha ◽  
Yonathan Yonathan ◽  
Rury Eprilurahman ◽  
Septiana Indriawan ◽  
Eka Cahyaningrum

Merapi volcano as one of national park is an ecotourism site which is very potential to visit. Information about species diversity for a national park is very important especially if its area fluctuated susceptibly. Two years after 2010 Merapi eruption, there are no research about species diversity and evenness of Anuran in that place. The research is carried out during June-November 2012 which is dry season. The objective of this research is to study the species diversity and evenness of Anuran in southern slope of Mount Merapi. The research is carried out in 6 locations; those are Kali Kuning, Telogo Muncar, Telogo Nirmolo, Petak Pitu, Bukit Turgo, and Bukit Plawangan. We used Visual Encounter Survey (VES) method combined with transect in Kali Kuning, Telogo Muncar, and Petak Pitu. VES method combined with time search in Telogo Nirmolo and Bukit Turgo. VES method combined with track exploration in Bukit Plawangan. Species diversity is analyzed with Shanon-Wiener diversity index. Species evenness is analyzed with Pielou evenness index. Total individuals each species is counted to know species abundance. Species diversity of anuran in southern slope of Mount Merapi is consisted of 12 species’ which is distributed in 6 locations. The highest diversity and evenness of anuran is at Bukit Turgo (H’=1.31; E=0.94). The lowest diversity and evenness of anuran is at Petak Pitu (H’=0.49; E=0.3). Species diversity of anuran in southern slope of Mount Merapi is low (Bukit Turgo and Kali Kuning) and very low (Bukit Plawangan, Telogo Muncar, Telogo Nirmolo, and Petak Pitu). Species evenness of anuran in southern slope of Mount Merapi is stable (Telogo Nirmolo and Bukit Turgo), still labil (Bukit Plawangan, Kali Kuning, and Telogo Muncar), and oppressed (Petak Pitu).


2021 ◽  
Vol 25 (8) ◽  
pp. 1415-1419
Author(s):  
O.M. Ogundele ◽  
P.O. Ige ◽  
Y.T. Owoeye ◽  
D.E. Abanikanda ◽  
O.O. Komolafe

This study was carried out to examine the tree species diversity and abundance in a natural forest ecosystem in the Southwestern region of Nigeria. Data were collected from a four equal size sampling plot of 50×50m in a permanent sample plot section of Akure Forest Reserve. All living trees with DBH ≥ 10cm were measured and identified. A total of 956 trees were encountered. These trees were from 42 genera and 20 families. Celtis zenkeri belonging to the family of Ulmaceae was the species with the highest population distribution while Sterculiaceae was the dominant family in the study area. The Shannon-Wiener Diversity Index (Hˈ) of 3.196 and species evenness of 0.84 were obtained from the study area. The high values of diversity indices obtained indicated that the forest is rich in biodiversity and hence should be protected from any forms of disturbance to enhance sustainability as well as protect the rare species in it from going into extinction.


2021 ◽  
Vol 22 (9) ◽  
Author(s):  
Amandita Lintang Rumondang ◽  
CECEP KUSMANA ◽  
SRI WILARSO BUDI

Abstract. Rumondang AL, Kusmana C, Budi SW. 2021. Species composition and structure of Angke Kapuk Mangrove Protected Forest, Jakarta, Indonesia. Biodiversitas 22: 3863-3871. Angke Kapuk Mangrove Protected Forest (AKMPF) is one of the protected forests in the coastal area of DKI Jakarta, Indonesia. This area is important for the north coast of Jakarta, hence it has function to protect the land from sea abrasion, seawater intrusion, and seawater flooding. This study aims to determine the condition of forest structures and species composition in the Angke Kapuk Mangrove Protected Forest (AKMPF) to obtain useful information for sustainable mangrove forest management. Vegetation data were collected using the sampling unit of transect for tree and line plot for forest regeneration inventories. Those data were analyzed for the density, frequency, dominance, species diversity, and species distribution pattern. The obtained results show that AKMPF consists of 13 mangrove species, including 7 species of true mangrove, 5 species associated mangrove, and 1 species of palm, with the dominant species, are Avicennia marina for tree with its regenerations and Acrostichum aureum for groundcover. Overall, the species diversity index in this area was classified as low category. Mangrove trees in this area have height class between 4-28 meters formed bell-curve, while stem diameter class were between 10.00-69.75 cm formed L-curve. The distribution pattern of species in this areal generally was clumped.


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