scholarly journals Forecasting the impact of an invasive macrophyte species in the littoral zone through aquatic insect species composition

2017 ◽  
Vol 107 (0) ◽  
Author(s):  
Hugo H. L. Saulino ◽  
Susana Trivinho-Strixino
2020 ◽  
Vol 20 (3) ◽  
pp. 267-276
Author(s):  
Dam Duc Tien ◽  
Nguyen Thi Mai Anh ◽  
Linh Manh Nguyen ◽  
Pham Thu Hue ◽  
Lawrence Liao

This paper exhibites species composition and distribution of marine seaweed at 10 sites of Co To and Thanh Lan islands in May 2019. The studies record 76 species of marine algae in the area, belonging to four divisions: Cyanophytes, Rhodophytes, Ochrophytes and Chlorophytes. Among them, five species are classified into Cyanophytes (comprising 6.6% of total species); thirty-four species into Rhodophytes (44.7%); twenty-one species into Ochrophytes/Phaeophytes (27.6%) and sixteen species into Chlorophytes (21.1%). The species composition of marine seaweeds in Co To and Thanh Lan shows significant differences as follows: 22 species (sites number 4 and 10) to 58 species (site number 2) and the average value is 38.7 species per site. Sørensen similarity coefficient fluctuates from 0.33 (sites number 5 and 10) to 0.84 (sites number 1 and 3) and the average value is 0.53. The current investigations show that four species of twenty-one species are collected in the littoral zone and forty-two species in the sub-littoral zone (in which there are thirteen species distributed in both littoral zone and sub-littoral zone). The algal flora in Co To and Thanh Lan is characterized by subtropics.


Author(s):  
Nguyen Van Hieu ◽  
Nguyen Van Vinh

An intensive field survey on aquatic insects of Me Linh Station for Biodiversity in Vinhphuc province was conducted in December 2015. Specimens were collected at 8 different sites and aquatic insects were collected both quantitatively by Surber net and qualitatively by hand net, pond net. As a result, a total of 110 aquatic insect species belonging to 98 genera, 49 families and 9 orders were recognized. Among these, the order Ephemeroptera had the highest species number with 26 species, followed by Odonata with 25 species, Trichoptera with 18 species, Coleoptera with 15 species, Hemiptera with 11 species, Diptera with 9 species. Lepidoptera, Plecoptera and Megaloptera had the lowest of species number, represented by 3 species of Lepidoptera, 2 species of Plecoptera and 1 species of Megaloptera. Besides, the quantitative analysis results and the functional feeding groups were provided.


Biologia ◽  
2017 ◽  
Vol 72 (7) ◽  
Author(s):  
Mária Petrášová-Šibíková ◽  
Igor Matečný ◽  
Eva Uherčíková ◽  
Peter Pišút ◽  
Silvia Kubalová ◽  
...  

AbstractHuman alteration of watercourses is global phenomenon that has had significant impacts on local ecosystems and the services they provide. Monitoring of abiotic and biotic changes is essential to mitigating long-lasting effects, and the 23-year dataset from the Gabčíkovo Waterworks provided a rare opportunity to assess the impact of groundwater regimes on vegetation. The main aim of this study was to describe the effect of the Gabčíkovo Waterworks on vegetation structure and species composition of the adjacent riparian floodplain forests over the past 23 years. The results are based on studies of three permanent monitoring plots (PMPs) located in the Danube inland delta – two outside (PMP 1 and 3) and one (PMP 2) fully under the influence of the artificial supply system. Our results demonstrate that the Danube inland delta was negatively affected by the Gabčíkovo construction, particularly for sites outside of the artificial supply system. There was a significant decrease in soil moisture and increase in nitrogen at both external PMPs (1 and 3). Alter soil conditions were accompanied by negative changes in plant species composition demonstrated by decreases in the number of typical floodplain forest species that are characteristic for the alliance


2012 ◽  
Vol 27 (2) ◽  
pp. 117-129 ◽  
Author(s):  
Farag Mahmoud

A survey of insects associated with sesame, Sesamun indicum L. (Pedaliaceae) was conducted at the Agriculture Research Farm of The Faculty of Agriculture, University of Suez Canal during the growing seasons 2010 and 2011. All different insect species found on the experimental site were collected for identification. Sampling was done once a week and three times a day. Three methods were used to collect insects from the sesame plants (a sweep net, pitfall traps, digital camera and eye observation). A total of 31 insect species were collected and properly identified during the survey. Insects recorded on the plants were divided into four groups, true pollinators (Hymenoptera), other pollinators (Diptera, Coleoptera and Lepidoptera), pests (Orthoptera, Odonata, Hemiptera and Homoptera) and natural enemies (Coleoptera, Hymenoptera, Neuroptera and Dictyoptera). For studying the impact of insect pollination on sesame production, the experiment was divided in two: opened and non-opened pollination of sesame. 50 plants from nonopened pollination were covered with a perforated paper bag to allow the air to pass through and to prevent insects from approaching the plants. Quantitative and qualitative parameters were measured as follows: pod weight, number of seeds in each pod, weight of 1000 seeds, germination (%), seedlings vigour and oil content (%). Results clearly demonstrate that the opened pollination improved the crop production.


2019 ◽  
Vol 30 (2) ◽  
pp. 106-112
Author(s):  
T. M. Kolombar

Annually in the world, insect pests kill 10–15 % of the crop yield, which in the face of increasing humanity creates a global problem for food security. For the territory of Ukraine in some years, the loss of wheat yields reach 25 % and, in the face of this tendency, real risks to the security of the state are created. Considering that the agrarian trend of the state development has been increasing in recent years, the development of grain-adapted to the ecological and climatic conditions of Ukraine is a priority direction of the development of domestic agriculture. And the development of new environmentally friendly methods of controlling pests of wheat using parasitic organisms will become a fundamentally new and pressing issue in the development of organic production in the country. The general list of pest species that can cause serious wheat yield and forage reduction in Ukraine includes more than 230 names, but only 18 species are able toentail the biggest losses. Among them belong to the order Coleoptera. One insect species is usually a host of several species of mites, nematodes and up to ten species of gregarines and microsporidia. Unfortunately, the taxonomic composition of parasites of phytophagous pets of wheat in Ukraine has not been thoroughly investigated. We studied the interrelation between parasites of 4 phytophagous insects of wheat as well as of 14 insect species found in granaries. The study of the species composition of parasitic organisms of wheat and grain pests is based on the study of the elementary part of the consortium ecosystem, where they act as second order consortia. Phytophagous parasites of wheat and collar pests of cereals, as second-order consorts, have been fragmented worldwide. The purpose of this work is to determine the species composition of gregarine as a component of wheat consortium for their further use in the creation of integrated methods of protection of wheat and products of its processing. As a result, 28 species of gregarines were registered, which belong to seven families (Didymophyidae, Ophryocystidae, Hirmocystidae, Lipotrophidae, Stylocephalidae, Actinocephalidae and Gregarinidae). On the average, 1–2 species of gregarines parasitize in one pest species. 7–10 species of parasites were identified in some insects of the family Tenebrionidae (Tenebrio molitor Linnaeus, 1758 and Tribolium confusum Jacquelin du Val, 1863). Each presented parasite is characteristic of 1–2 species of pests, but there are species of gregarines that infect up to four species of model species, such as Gregarina cuneata Stein, 1848. The largest number of individuals who are infested with gregarines belong to such families as Tenebrionidae and Dermestidae (38,6 % and 36,0 % of the total number of species, respectively). On pests – phytophages parasitizes about 8 species of gregarine families Stylocephalidae, Gregarinidae, Actinocephalidae. For barns pests are recorded barnacles of all 7 families.


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