Search results for: aquatic insect
615 Effect of Climate Changing Pattern on Aquatic Biodiversity of Bhimtal Lake at Kumaun Himalaya (India)
Authors: Davendra S. Malik
Abstract:
Bhimtal lake is located between 290 21’ N latitude and 790 24’ E longitude, at an elevation of 1332m above mean sea level in the Kumaun region of Uttarakhand of Indian subcontinent. The lake surface area is decreasing in water area, depth level in relation to ecological and biological characteristics due to climatic variations, invasive land use pattern, degraded forest zones and changed agriculture pattern in lake catchment basin. The present study is focused on long and short term effects of climate change on aquatic biodiversity and productivity of Bhimtal lake. The meteorological data of last fifteen years of Bhimtal lake catchment basin revealed that air temperature has been increased 1.5 to 2.1oC in summer, 0.2 to 0.8 C in winter, relative humidity increased 4 to 6% in summer and rainfall pattern changed erratically in rainy seasons. The surface water temperature of Bhimtal lake showed an increasing pattern as 0.8 to 2.6 C, pH value decreased 0.5 to 0.2 in winter and increased 0.4 to 0.6 in summer. Dissolved oxygen level in lake showed a decreasing trend as 0.7 to 0.4mg/l in winter months. The mesotrophic nature of Bhimtal lake is changing towards eutrophic conditions and contributed for decreasing biodiversity. The aquatic biodiversity of Bhimtal lake consisted mainly phytoplankton, zooplankton, benthos and fish species. In the present study, a total of 5 groups of phytoplankton, 3 groups of zooplankton, 11 groups of benthos and 15 fish species were recorded from Bhimtal lake. The comparative data of biodiversity of Bhimtal lake since January, 2000 indicated the changing pattern of phytoplankton biomass were decreasing as 1.99 and 1.08% of Chlorophyceae and Bacilleriophyceae families respectively. The biomass of Cynophyceae was increasing as 0.45% and contributing the algal blooms during summer season in lake. The biomass of zooplankton and benthos were found decreasing in winter season and increasing during summer season. The endemic fish species (18 no.) were found in year 2000-05, as while the fish species (15 no.) were recorded in present study. The relative fecundity of major fish species were observed decreasing trends during their breeding periods in lake. The natural and anthropogenic factors were identified as ecological threats for existing aquatic biodiversity of Bhimtal lake. The present research paper emphasized on the effect of changing pattern of different climatic variables on species composition, biomass of phytoplankton, zooplankton, benthos, and fishes in Bhimtal lake of Kumaun region. The present research data will be contributed significantly to assess the changing pattern of aquatic biodiversity and productivity of Bhimtal lake with different time scale.Keywords: aquatic biodiversity, Bhimtal lake, climate change, lake ecology
Procedia PDF Downloads 212614 Global Climate Change and Insect Pollinators
Authors: Asim Abbasi, Muhammad Sufyan, Iqra, Muhammad Ibrahim Shahid, Muhammad Ashfaq
Abstract:
The foundation of human life on earth relies on many ecosystem services provided by insects of which pollination owes a vital role. The pollination service offered by insects has annual worth of approximately €153 billion. The majority of the flowering plants depends on entomophiles pollination for their reproduction and formation of seeds and fruits. The quantity and quality of insect pollination have multiple implications for stable ecosystem, diverse species level, food security and climate change resilience. The rapidly mounting human population, depletion of natural resources and the global climate change forced us to enter an era of pollination crisis. Climate change not only alters the phenology, population abundance and geographic ranges of different pollinators but also hinders their pollination activities. The successful pollination process relies heavily on the synchronization of biological events of pollinators with the phenological stages of the flowering plants. However, there are possibilities that impending climatic changes may result in asynchrony between plant-pollinators interactions and also mitigate the extent of pollination. The trophic mismatch mostly occurs when pollinators and plants inhabiting the same environment use different environmental cues to regulate their biological events, as these cues are not equally affected by climate change. Synchrony has also been disrupted when one of the interacting species has migratory nature and depend on cues for migration. Moreover, irregular rainfalls and up-surging temperature also disrupts the foraging behaviour of pollinators resulting in reduced flowers visits by insect. Climate change has a direct impact on the behavior and physiology of honey bees, the best known pollinators owing to their extreme floral fidelity. Rising temperature not only alleviates the quantity and quality of floral environment but also alters the bee’s colony harvesting and development ability. Furthermore, a possible earlier decline of flowers is expected in a growing season due to this rising temperature. This may also lead to disrupt the efficiency bumblebee queen that require a constant and adequate nectar and pollen supply throughout the entire growing season for healthy colony production. Considering the role of insect pollination in our ecosystem, their associated risks regarding climate change should be addressed properly for devising a well-focused research needed for their conservation.Keywords: climate change, phenological, pollination, synchronization
Procedia PDF Downloads 211613 Interaction of Steinernema Glaseri, an Entomopathogenic Nematode with a Predatory Fungus Arthrobotrys Superba on Different Nutrient Media
Authors: Varsha Baweja
Abstract:
Steinernema glaseri is known to be the most potent biocontrol agent against a number of insect pests of various orders and of diverse habitats under laboratory conditions. But in nature many micro pathogens may affect the efficacy of such entomopathogenic nematodes. Keeping this in view, the interaction of Steinernema glaseri with a predatory fungus Arthrobotrys superba was assessed on eight different nutrient media. The activity of A.superba was evaluated in terms of trap formation, conidiophore formation, and number of adhesive cells formed in the presence and absence of nematodes. The fungus failed to form any trap on any of the culture media in the absence of nematodes. However, in the presence of nematodes, the trap formation by the test fungus was increased but the number of conidiophores decreased with increase in dilution of Corn Meal Agar from 5% to 2%. Higher number of chlamydospores were observed in phenylalanine treated medium which indicates the inhibiting effect of phenylalanine on the growth of A. superba. Our results suggest that care should be taken during release of entomopathogenic nematodes in an agroecosystem for managing various insect pests in a more efficient manner.Keywords: Entomopathogenic Nematode , Steinernema Glaseri, Predatory Fungus, Arthrobotrys Superba
Procedia PDF Downloads 274612 Bio–efficacy of Selected Plant extracts and Cypermethrin on Growth and Yield of Cowpea (Vigna unguiculata L.).
Authors: Akanji Kayode Ayanwusi., Akanji Elizabeth Nike, Bidmos Fuad Adetunji, Oladapo Olufemi Stephen
Abstract:
This experiment was conducted in Igboora, southwest Nigeria during the year 2022 planting season to determine the bio-efficacy of plant extracts (Jatropha curcas and Petiveria alliacea) and synthetic (Cypermethrin) insecticides against the insect pest of cowpea (Vigna unguiculata L.) and to determine its effect on the growth and yield of cowpea in the study area. Cowpea is one of the most important food and forage legumes in the semi-arid tropics. It is grown in 45 countries worldwide, including parts of Africa, Asia, Southern Europe, the Southern United States, and Central and South America. Cowpea production is considered too risky an enterprise by many growers because of its numerous pest problems. The treatments for the experiment consisted of two aqueous plant extracts (J.curcas and P. alliacea) at 50 /0 w/v and Cypermethrin 400 EC replicated three times including control in a randomized complete block design. Each plot measured 2.0 m by 2.0 m with 1.0 m inter-spaced per adjacent plot. The results from the study showed that different insect pests attack cowpea at different stages of growth. The insects observed were Bemisa tabaci, Callosobruchus maculatus, Megalurothrips sjostedti, and Maruca vitrata. High yields were obtained from plots treated with P. alliacea and synthetic insecticide (cypermethrin). J. curcas also produced optimum yield but lower than P. alliacea also P. alliacea treated plots had the least damaged pods while the untreated plots had the highest damaged pods, the plants extracts exhibited high insecticidal activities in this study, therefore P. alliacea leaves formulated as an insecticide is recommended for the control of insect pests of cowpea in the study area.Keywords: plant extracts, yield, cypermethrin., cowpea
Procedia PDF Downloads 83611 Sulfamethoxazole Degradation by Conventional Fenton and Microwave-Assisted Fenton Reaction
Authors: Derradji Chebli, Abdallah Bouguettoucha, Zoubir Manaa, Amrane Abdeltif
Abstract:
Pharmaceutical products, such as sulfamethoxazole (SMX) are rejected in the environment at trace level by human and animals (ng/L to mg/L), in their original form or as byproducts. Antibiotics are toxic contaminants for the aquatic environment, owing to their adverse effects on the aquatic life and humans. Even at low concentrations, they can negatively impact biological water treatment leading to the proliferation of antibiotics-resistant pathogens. It is therefore of major importance to develop efficient methods to limit their presence in the aquatic environment. In this aim, advanced oxidation processes (AOP) appear relevant compared to other methods, since they are based on the production of highly reactive free radicals, and especially ●OH. The objective of this work was to evaluate the degradation of SMX by microwave-assisted Fenton reaction (MW/Fe/H2O2). Hydrogen peroxide and ferrous ions concentrations, as well as the microwave power were optimized. The results showed that the SMX degradation by MW/Fe/H2O2 followed a pseudo-first order kinetic. The treatment of 20 mg/L initial SMX by the Fenton reaction in the presence of microwave showed the positive impact of this latter owing to the higher degradation yields observed in a reduced reaction time if compared to the conventional Fenton reaction, less than 5 min for a total degradation. In addition, increasing microwave power increased the degradation kinetics. Irrespective of the application of microwave, the optimal pH for the Fenton reaction remained 3. Examination of the impact of the ionic strength showed that carbonate and sulfate anions increased the rate of SMX degradation.Keywords: antibiotic, degradation, elimination, fenton, microwave, polluant
Procedia PDF Downloads 389610 Short-Term Effects of Environmentally Relevant Concentrations of Organic UV Filters on Signal Crayfish Pacifastacus Leniusculus
Authors: Viktoriia Malinovska, Iryna Kuklina, Katerina Grabicova, Milos Buric, Pavel Kozak
Abstract:
Personal care products, including organic UV filters, are considered emerging contaminants and their toxic effects have been a concern for the last decades. Sunscreen compounds continually enter the surface waters via sewage water treatment due to incomplete removal and during human recreational and laundry activities. Despite the environmental occurrence of organic UV filters in the freshwater environment, little is known about their impacts on aquatic biota. In this study, environmentally relevant concentrations of 5-Benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid (BP-4, 2.5 µg/L) and 2-Phenylbenzimidazole-5-sulfonic acid (PBSA, 3 µg/L) were used to evaluate the cardiac and locomotor responses of signal crayfish Pacifastacus leniusculus during a short time period. The effects of these compounds were evident in experimental animals. Specimens exposed to both tested compounds exhibited significantly bigger changes in distance moved and time movement than controls. Significant differences in changes in mean heart rate were detected in both PBSA and BP-4 experimental groups compared to control groups. Such behavioral and physiological alterations demonstrate the ecological effects of selected sunscreen compounds during a short time period. Since the evidence of the impacts of sunscreen compounds is scarce, the knowledge of how organic UV filters influence aquatic organisms is of key importance for future research.Keywords: aquatic pollutants, behavior, freshwaters, heart rate, invertebrate
Procedia PDF Downloads 101609 Prevelance of Green Peach Aphid (Myzus persicae) in District Jacobabad, Sindh, Pakistran
Authors: Kamal Khan Abro, Nasreen Memon, Attaullah Ansari, Mahpara Pirzada, Saima Pathan
Abstract:
Jacobabad district has a hot desert climate with very hot summers and insignificant winters. The highest recorded temperature is 53.8 °C (127.0 °F), and the lowest recorded temperature is −4.9 °C (25.0 °F). Rainfall is short and mostly occurs in the monsoon season (July–September). Agriculture point of view Jacobabad district is very important district of Sindh Pakistan in which many types of crop and vegetables are cultivated annually such as Wheat, Rice, and Brassica, Cabbage, Spinach, Chili etc. which are badly attacked by many crops pest. Insects are very tiny, sensitive and most attractive mortal and most important collection of animal wildlife they play important role in biological control agent, biodiversity & agroecosystem. The brassica crop extremely infested by many different types of pest such as Aphids, Whitefly, Jassids, Thrips, Mealybug, scale insect pink worm, bollworm and borers Mealy bug, scale insect etc. These pests destroy many crops. The present study was carried out from Jacobabad district from January 2017 to April 2017.Keywords: prevelance, green peach aphid, Jacobabad, Sindh Pakistan
Procedia PDF Downloads 280608 Efficacy of Defender 2% WS (Tebuconazole) and Imidal 70 WS (Imidacloprid) to Control Damping-Off Diseases and Early Insect Pests in Sesame in Rain Fed Areas, Sudan
Authors: Anas Fadlelmula, Elsafi M. M. Ahmed
Abstract:
The efficacy of Defender 2% WS (tebuconazole) and Imidal 70 WS (imidacloprid) to control damping-off diseases and early insect pests in sesame crop under rain fed conditions at Damazine and Gedarif areas was evaluated. Defender 2% WS with dosage rates 0.5, 0.75, 1.0 and 1.25 g/kg of seeds and Imidal 70 WS at 2.25, 3.0, and 3.75 g/ kg of seeds were tested singly and as a mixture during 2010/2011 and 2012/013. Sesame seeds treated with Defender at the rates of 0.5 g and 0.75 g/ kg of seeds gave a high significant increase in percent seedlings emergence (84% and 85%) respectively. Imidal 70 WS at rate of 3g/kg seed showed the least percent damaged leaves by sesame webworm (1.7%). However, the mixed Defender at rate 0.75g with Imidal at 3 g/kg seed, significantly gave a highest percentage of sesame seedling emergence (85.1%) and reduced the incidence of post-emergence damping off and percent damaged leaves to the least per cent (2.1% and 0.4% ) respectively, compared to other treatments. Consequently, the mixed treatment of 0.75 g of Defender + 3 g of Imidal improved the crop stand and significantly gave the highest yield (405.2 kg and 418.8 kg/fed) respectively in both sites compared to the other treatments.Keywords: seed dressers, damage, daming off, insects
Procedia PDF Downloads 261607 The Effect of Electric Field Distributions on Grains and Insect for Dielectric Heating Applications
Authors: S. Santalunai, T. Thosdeekoraphat, C. Thongsopa
Abstract:
This paper presents the effect of electric field distribution which is an electric field intensity analysis. Consideration of the dielectric heating of grains and insects, the rice and rice weevils are utilized for dielectric heating analysis. Furthermore, this analysis compares the effect of electric field distribution in rice and rice weevil. In this simulation, two copper plates are used to generate the electric field for dielectric heating system and put the rice materials between the copper plates. The simulation is classified in two cases, which are case I one rice weevil is placed in the rice and case II two rice weevils are placed at different position in the rice. Moreover, the probes are located in various different positions on plate. The power feeding on this plate is optimized by using CST EM studio program of 1000 watt electrical power at 39 MHz resonance frequency. The results of two cases are indicated that the most electric field distribution and intensity are occurred on the rice and rice weevils at the near point of the probes. Moreover, the heat is directed to the rice weevils more than the rice. When the temperature of rice and rice weevils are calculated and compared, the rice weevils has the temperature more than rice is about 41.62 Celsius degrees. These results can be applied for the dielectric heating applications to eliminate insect.Keywords: capacitor copper plates, electric field distribution, dielectric heating, grains
Procedia PDF Downloads 400606 Application of Aquatic Plants for the Remediation of Organochlorine Pesticides from Keenjhar Lake
Authors: Soomal Hamza, Uzma Imran
Abstract:
Organochlorine pesticides bio-accumulate into the fat of fish, birds, and animals through which it enters the human food cycle. Due to their persistence and stability in the environment, many health impacts are associated with them, most of which are carcinogenic in nature. In this study, the level of organochlorine pesticides has been detected in Keenjhar Lake and remediated using Rhizoremediation technique. 14 OC pesticides namely, Aldrin, Deldrin, Heptachlor, Heptachlor epoxide, Endrin, Endosulfun I and II, DDT, DDE, DDD, Alpha, Beta, Gamma BHC and two plants namely, Water Hyacinth and Slvinia Molesta were used in the system using pot experiment which processed for 11 days. A consortium was inoculated in both plants to increase its efficiency. Water samples were processed using liquide-liquid extraction. Sediments and roots samples were processed using Soxhlet method followed by clean-up and Gas Chromatography. Delta-BHC was the predominantly found in all samples with mean concentration (ppb) and standard deviation of 0.02 ± 0.14, 0.52 ± 0.68, 0.61 ± 0.06, in Water, Sediments and Roots samples respectively. The highest levels were of Endosulfan II in the samples of water, sediments and roots. Water Hyacinth proved to be better bioaccumulaor as compared to Silvinia Molesta. The pattern of compounds reduction rate by the end of experiment was Delta-BHC>DDD > Alpha-BHC > DDT> Heptachlor> H.Epoxide> Deldrin> Aldrin> Endrin> DDE> Endosulfun I > Endosulfun II. Not much significant difference was observed between the pots with the consortium and pots without the consortium addition. Phytoremediation is a promising technique, but more studies are required to assess the bioremediation potential of different aquatic plants and plant-endophyte relationship.Keywords: aquatic plant, bio remediation, gas chromatography, liquid liquid extraction
Procedia PDF Downloads 140605 Severe Infestation of Laspeyresia Koenigana Fab. and Alternaria Leaf Spot on Azadirachta Indica (Neem)
Authors: Shiwani Bhatnagar, K. K. Srivastava, Sangeeta Singh, Ameen Ullah Khan, Bundesh Kumar, Lokendra Singh Rathore
Abstract:
From the instigation of the world medicinal plants are treated as part and parcel of human society to fight against diseases. Azadirachta indica (Neem) a herbal plant has been used as an Indian traditional medicine since ages and its products are acknowledged to solve agricultural, forestry and public health related problems, owing to its beneficial medicinal properties. Each part of the neem tree is known for its medicinal property. Bark & leaf extracts of neem have been used to control leprosy, respiratory disorders, constipation and also as blood purifier and a general health tonic. Neem is still regarded as ' rural community dispensary' in India or a tree for solving medical problems. Use of Neem as pesticides for the management of insect pest of agriculture crops and forestry has been seen as a shift in the use of synthetic pesticides to ecofriendly botanicals. Neem oil and seed extracts possess germicidal and anti-bacterial properties which when sprayed on the plant helps in protecting them from foliage pests. Azadirachtin, the main active ingredient found in neem tree, acts as an insect repellent and antifeedant. However the young plants are susceptible to many insect pest and foliar diseases. Recently, in the avenue plantation, planted by Arid Forest Research Institute, Jodhpur, around the premises of IIT Jodhpur, two years old neem plants were found to be severely infested with tip borer Laspeyresia koenigana (Family: Eucosmidae). The adult moth of L. koenigana lays eggs on the tender shoots and the young larvae tunnel into the shoot and feed inside. A small pinhole can be seen at the entrance point, from where the larva enters in to the stem. The severely attached apical shoots exhibit profuse gum exudation resulting in development of a callus structure. The internal feeding causes the stem to wilt and the leaves to dry up from the tips resulting in growth retardation. Alternaria Leaf spot and blight symptoms were also recorded on these neem plants. For the management of tip borer and Alternaria Leaf spot, foliar spray of monocrotophos @0.05% and Dithane M-45 @ 0.15% and powermin @ 2ml/lit were found efficient in managing the insect pest and foliar disease problem. No Further incidence of pest/diseases was noticed.Keywords: azadirachta indica, alternaria leaf spot, laspeyresia koenigana, management
Procedia PDF Downloads 467604 Bioremediation of Arsenic from Industrially Polluted Soil of Vatva, Ahmedabad, Gujarat, India
Authors: C. Makwana, S. R. Dave
Abstract:
Arsenic is toxic to almost all living cells. Its contamination in natural sources affects the growth of microorganisms. The presence of arsenic is associated with various human disorders also. The attempt of this sort of study provides information regarding the performance of our isolated microorganisms in the presence of Arsenic, which have ample scope for bioremediation. Six isolates were selected from the polluted sample of industrial zone Vatva, Ahmedabad, Gujarat, India, out of which two were Thermophilic organisms. The thermophilic exopolysaccharide (EPS) producing Bacillus was used for microbial enhance oil recovery (MEOR) and in the bio beneficiation. Inorganic arsenic primarily exists in the form of arsenate or arsenite. This arsenic resistance isolate was capable of transforming As +3 to As+5. This isolate would be useful for arsenic remediation standpoint from aquatic systems. The study revealed that the thermophilic microorganism was growing at 55 degree centigrade showed considerable remediation property. The results on the growth and enzyme catalysis would be discussed in response to Arsenic remediation.Keywords: aquatic systems, thermophilic, exopolysacchride, arsenic
Procedia PDF Downloads 210603 Using OMICs Approaches to Investigate Venomic Insights into the Spider Web Silk
Authors: Franciele G. Esteves, Jose R. A. dos Santos-Pinto, Caroline L. de Souza, Mario S. Palma
Abstract:
Orb-weaving spiders use a very strong, stickiness, and elastic web to catch the prey. These web properties would be enough for the entrapment of prey; however, these spiders may be hiding venomous secrets on the web, which are being revealed now. Here we provide strong proteome, peptidome, and transcriptomic evidence for the presence of toxic components on the web silk from Nephila clavipes. Our scientific outcomes revealed, both in the web silk and in the silk-producing glands, a wide diversity of toxins/neurotoxins, defensins, and proteolytic enzymes. These toxins/neurotoxins are similar to toxins isolated from animal venoms, such as Sphigomyelinase D, Latrotoxins, Zodatoxins, Ctenitoxin Pn and Pk, Agatoxins and Theraphotoxin. Moreover, the insect-toxicity results with the web silk crude extract demonstrated that these toxic components can be lethal and/or cause paralytic effects to the prey. Therefore, through OMICs approaches, the results presented until now may contribute to a better understanding of the chemical and ecological interaction of these compounds in insect-prey capture by spider web N. clavipes, demonstrating that the web is not only a simple mechanical tool but has a chemical-active involvement in prey capture. Moreover, the results can also contribute to future studies of possible development of a selective insecticide or even in possible pharmacological applications.Keywords: web silk toxins, silk-produncing glands, de novo transcriptome assembly, LCMS-based proteomics
Procedia PDF Downloads 127602 Practices of Entomophagy and Entomotherapy in Baranggay Alambijud, Argao and Baranggay Lusaran, Cebu City, Philippines
Authors: Jake Joshua C. Garces, Zandra O. Jarito, Leslie Ann T. Barriga, Froilen C. Domicelo, Nimfa R. Pansit
Abstract:
The study was conducted in order to discover the medicinal and edible potentialities of different insect species in Baranggay Alambijud, Argao and Baranggay Lusaran, Cebu City, Cebu. In order to identify these entomological practices, a survey was carried out by the researchers in these key sites. Fourteen key informants were obtained and these were identified with the aide of two sampling methods- snowball technique and purposive sampling. Open-ended questionnaires were employed in order to obtain authentic and significant information from the key informants. Results portrayed that in the practice of entomotherapy, two insects were used as medicine namely: migratory locust (Locusta migratoria manillensis) and honey bee (Apis dorsata); and two insect by-products were utilized namely: feces of cockroach (Periplaneta Americana) and honey. White grub (Cotinis nitida) and bee eggs were also documented to manifest edible capability and were thus utilized in the entomophagic practices. After applying thematic analysis, it was determined that the causative factors of their entomological practices include their limited educational attainment, their inability to access urban societies and the influence brought about by their family and community.Keywords: entomophagy, entomotherapy, entomology, key informants
Procedia PDF Downloads 332601 Molecular Diversity of Forensically Relevant Insects from the Cadavers of Lahore
Authors: Sundus Mona, Atif Adnan, Babar Ali, Fareeha Arshad, Allah Rakha
Abstract:
Molecular diversity is the variation in the abundance of species. Forensic entomology is a neglected field in Pakistan. Insects collected from the crime scene should be handled by forensic entomologists who are currently virtually non-existent in Pakistan. Correct identification of insect specimen along with knowledge of their biodiversity can aid in solving many problems related to complicated forensic cases. Inadequate morphological identification and insufficient thermal biological studies limit the entomological utility in Forensic Medicine. Recently molecular identification of entomological evidence has gained attention globally. DNA barcoding is the latest and established method for species identification. Only proper identification can provide a precise estimation of postmortem intervals. Arthropods are known to be the first tourists scavenging on decomposing dead matter. The objective of the proposed study was to identify species by molecular techniques and analyze their phylogenetic importance with barcoded necrophagous insect species of early succession on human cadavers. Based upon this identification, the study outcomes will be the utilization of established DNA bar codes to identify carrion feeding insect species for concordant estimation of post mortem interval. A molecular identification method involving sequencing of a 658bp ‘barcode’ fragment of the mitochondrial cytochrome oxidase subunit 1 (CO1) gene from collected specimens of unknown dipteral species from cadavers of Lahore was evaluated. Nucleotide sequence divergences were calculated using MEGA 7 and Arlequin, and a neighbor-joining phylogenetic tree was generated. Three species were identified, Chrysomya megacephala, Chrysomya saffranea, and Chrysomya rufifacies with low genetic diversity. The fixation index was 0.83992 that suggests a need for further studies to identify and classify forensically relevant insects in Pakistan. There is an exigency demand for further research especially when immature forms of arthropods are recovered from the crime scene.Keywords: molecular diversity, DNA barcoding, species identification, forensically relevant
Procedia PDF Downloads 139600 Insect Manure (Frass) as a Complementary Fertilizer to Enhance Soil Mineralization Function: Application to Cranberry and Field Crops
Authors: Joël Passicousset, David Gilbert, Chloé Chervier-Legourd, Emmanuel Caron-Garant, Didier Labarre
Abstract:
Living soil agriculture tries to reconciliate food production while improving soil health, soil biodiversity, soil fertility and more generally attenuating the inherent environmental drawbacks induced by modern agriculture. Using appropriate organic materials as soil amendments has a role to play in the aim of increasing the soil organic matter, improving soil fertility, sequestering carbon, and diminishing the dependence on both mineral fertilizer and pesticides. Insect farming consists in producing insects that can be used as a rich-in-protein and entomo-based food. Usually, detritivores are chosen, thus they can be fed with food wastes, which contributes to circular economy while producing low-carbon food. This process also produces frass, made of insect feces, exuvial material, and non-digested fibrous material, that have valuable fertilizer and biostimulation properties. But frass, used as a sole fertilizer on a crop may be not completely adequate for plants’ needs. This is why this project considers black soldier fly (termed BSF, one of the three main insect species grown commercially) frass as a complementary fertilizer, both in organic and in conventional contexts. Three kinds of experiments are made to understand the behaviour of fertilizer treatments based on frass incorporation. Lab-scale mineralization experiments suggest that BSF frass alone mineralizes more slowly than chicken manure alone (CM), but at a ratio of 90% CM-10% BSF frass, the mineralization rate of the mixture is higher than both frass and CM individually. For example, in the 7 days following the fertilization with same nitrogen amount introduced among treatments, around 80% of the nitrogen content supplied through 90% CM-10% BSF frass fertilization is present in the soil under mineral forms, compared to roughly 60% for commercial CM fertilization and 45% with BSF-frass. This suggests that BSF frass contains a more recalcitrant form of organic nitrogen than CM, but also that BSF frass has a highly active microbiota that can increase CM mineralization rate. Consequently, when progressive mineralization is needed, pure BSF-frass may be a consistent option from an agronomic aspect whereas, for specific crops that require spikes of readily available nitrogen sources (like cranberry), fast release 90CM-10BSF frass biofertilizer are more appropriate. Field experiments on cranberry suggests that, indeed, 90CM-10BSF frass is a potent candidate for organic cranberry production, as currently, organic growers rely solely on CM, whose mineralization kinetics are known to imperfectly match plant’s needs, which is known to be a major reason that sustains the current yield gap between conventional and organic cranberry sectors.Keywords: soil mineralization, biofertilizer, BSF-frass, chicken manure, soil functions, nitrogen, soil microbiota
Procedia PDF Downloads 63599 Simulating the Effect of Chlorine on Dynamic of Main Aquatic Species in Urban Lake with a Mini System Dynamic Model
Authors: Zhiqiang Yan, Chen Fan, Beicheng Xia
Abstract:
Urban lakes play an invaluable role in urban water systems such as flood control, landscape, entertainment, and energy utilization, and have suffered from severe eutrophication over the past few years. To investigate the ecological response of main aquatic species and system stability to chlorine interference in shallow urban lakes, a mini system dynamic model, based on the competition and predation of main aquatic species and TP circulation, was developed. The main species of submerged macrophyte, phytoplankton, zooplankton, benthos and TP in water and sediment were simulated as variables in the model with the interference of chlorine which effect function was attenuation equation. The model was validated by the data which was investigated in the Lotus Lake in Guangzhou from October 1, 2015 to January 31, 2016. Furthermore, the eco-exergy was used to analyze the change in complexity of the shallow urban lake. The results showed the correlation coefficient between observed and simulated values of all components presented significant. Chlorine showed a significant inhibitory effect on Microcystis aeruginosa,Rachionus plicatilis, Diaphanosoma brachyurum Liévin and Mesocyclops leuckarti (Claus).The outbreak of Spiroggra spp. inhibited the growth of Vallisneria natans (Lour.) Hara, caused a gradual decrease of eco-exergy, reflecting the breakdown of ecosystem internal equilibria. It was concluded that the study gives important insight into using chlorine to achieve eutrophication control and understand mechanism process.Keywords: system dynamic model, urban lake, chlorine, eco-exergy
Procedia PDF Downloads 202598 Releasing Two Insect Predators to Control of Aphids Under Open-field Conditions
Authors: Mohamed Ahmed Gesraha, Amany Ramadan Ebeid
Abstract:
Aphids are noxious and serious persistent pests in the open fields worldwide. Many authors studied the possibility of aphid control by applying Ladybirds and Lacewings at different releasing rates under open-field conditions. Results clarify that releasing 3rd instar larvae of Coccinella undecimpunctata at the rate of 1 larva:50 aphid was more effective than 1:100 or 1:200 rates for controlling Aphis gossypii population in Okra field; reflecting more than 90% reduction in the aphid population within 15 days. When Chrysoperla carnea 2nd larval instar were releasing at 1:5, 1:10, and 1:20 (predator: aphid), it was noticed that the former rate was the most effective one, inducing 98.93% reduction in aphid population; while the two other rates reflecting less reduction. Additionally, in the case of double releases, the reduction percentage at the 1:5 rate was 99.63%, emphasize that this rate was the most effective one; the other rates induced 97.05 and 95.64% reduction. Generally, a double release was more effective in all tested rates than the single one because of the cumulative existence of the predators in large numbers at the same period of the experiment. It could be concluded that utilizing insect predators (Coccinella undecimpunctata or Chrysoperla carnea) at an early larval stag were faire enough to reduce the aphids’ populations under open fields conditions.Keywords: releasing predators, lacewings, ladybird, open fields
Procedia PDF Downloads 168597 Construction of Submerged Aquatic Vegetation Index through Global Sensitivity Analysis of Radiative Transfer Model
Authors: Guanhua Zhou, Zhongqi Ma
Abstract:
Submerged aquatic vegetation (SAV) in wetlands can absorb nitrogen and phosphorus effectively to prevent the eutrophication of water. It is feasible to monitor the distribution of SAV through remote sensing, but for the reason of weak vegetation signals affected by water body, traditional terrestrial vegetation indices are not applicable. This paper aims at constructing SAV index to enhance the vegetation signals and distinguish SAV from water body. The methodology is as follows: (1) select the bands sensitive to the vegetation parameters based on global sensitivity analysis of SAV canopy radiative transfer model; (2) take the soil line concept as reference, analyze the distribution of SAV and water reflectance simulated by SAV canopy model and semi-analytical water model in the two-dimensional space built by different sensitive bands; (3)select the band combinations which have better separation performance between SAV and water, and use them to build the SAVI indices in the form of normalized difference vegetation index(NDVI); (4)analyze the sensitivity of indices to the water and vegetation parameters, choose the one more sensitive to vegetation parameters. It is proved that index formed of the bands with central wavelengths in 705nm and 842nm has high sensitivity to chlorophyll content in leaves while it is less affected by water constituents. The model simulation shows a general negative, little correlation of SAV index with increasing water depth. Moreover, the index enhances capabilities in separating SAV from water compared to NDVI. The SAV index is expected to have potential in parameter inversion of wetland remote sensing.Keywords: global sensitivity analysis, radiative transfer model, submerged aquatic vegetation, vegetation indices
Procedia PDF Downloads 252596 Pioneering Conservation of Aquatic Ecosystems under Australian Law
Authors: Gina M. Newton
Abstract:
Australia’s Environment Protection and Biodiversity Conservation Act (EPBC Act) is the premiere, national law under which species and 'ecological communities' (i.e., like ecosystems) can be formally recognised and 'listed' as threatened across all jurisdictions. The listing process involves assessment against a range of criteria (similar to the IUCN process) to demonstrate conservation status (i.e., vulnerable, endangered, critically endangered, etc.) based on the best available science. Over the past decade in Australia, there’s been a transition from almost solely terrestrial to the first aquatic threatened ecological community (TEC or ecosystem) listings (e.g., River Murray, Macquarie Marshes, Coastal Saltmarsh, Salt-wedge Estuaries). All constitute large areas, with some including multiple state jurisdictions. Development of these conservation and listing advices has enabled, for the first time, a more forensic analysis of three key factors across a range of aquatic and coastal ecosystems: -the contribution of invasive species to conservation status, -how to demonstrate and attribute decline in 'ecological integrity' to conservation status, and, -identification of related priority conservation actions for management. There is increasing global recognition of the disproportionate degree of biodiversity loss within aquatic ecosystems. In Australia, legislative protection at Commonwealth or State levels remains one of the strongest conservation measures. Such laws have associated compliance mechanisms for breaches to the protected status. They also trigger the need for environment impact statements during applications for major developments (which may be denied). However, not all jurisdictions have such laws in place. There remains much opposition to the listing of freshwater systems – for example, the River Murray (Australia's largest river) and Macquarie Marshes (an internationally significant wetland) were both disallowed by parliament four months after formal listing. This was mainly due to a change of government, dissent from a major industry sector, and a 'loophole' in the law. In Australia, at least in the immediate to medium-term time frames, invasive species (aliens, native pests, pathogens, etc.) appear to be the number one biotic threat to the biodiversity and ecological function and integrity of our aquatic ecosystems. Consequently, this should be considered a current priority for research, conservation, and management actions. Another key outcome from this analysis was the recognition that drawing together multiple lines of evidence to form a 'conservation narrative' is a more useful approach to assigning conservation status. This also helps to addresses a glaring gap in long-term ecological data sets in Australia, which often precludes a more empirical data-driven approach. An important lesson also emerged – the recognition that while conservation must be underpinned by the best available scientific evidence, it remains a 'social and policy' goal rather than a 'scientific' goal. Communication, engagement, and 'politics' necessarily play a significant role in achieving conservation goals and need to be managed and resourced accordingly.Keywords: aquatic ecosystem conservation, conservation law, ecological integrity, invasive species
Procedia PDF Downloads 126595 Composition, Abundance and Diversity of Zooplankton in Sarangani Bay, Sarangani Province, Philippines
Authors: Jeter Canete, Noreen Joyce Estrella, Yedda Sachi Patrice Madelo
Abstract:
Zooplankton plays a crucial role in aquatic ecosystems and a number of water parameters involved in it. Despite their relevance, there is inadequate information about zooplankton communities in Sarangani Bay, Sarangani Province: one of the most essential waterbodies in Mindanao. The aim of the present study was to determine the composition, abundance, and diversity of zooplankton as well as to provide more recent data about the physico-chemical characteristics of Sarangani Bay. Zooplankton samples were collected by vertical hauls using a zooplankton net (mouth diameter: 0.5m; mesh size opening: round, 350μm) in three stations in the coastal waters of Alabel, Malapatan, and Maasim during November 2018. A total of 74 species of zooplankton belonging mainly to Kingdom Protozoa, Phylum Arthropoda, Chaetognatha, and Chordata were identified. Results showed a total zooplankton abundance of 1,984,166 ind/m³ with the highest count recorded at Malapatan (717,169 ind/m³) and the lowest at Maasim (624,411 ind/m³). Among 22 zooplankton groups identified, subclass Copepoda was found to be the most dominant (73.10%), followed by Appendicularia (12.18%) and Vertebrata (3.54%). Diversity analysis revealed an even distribution of species and a diverse ecosystem in all stations sampled. Correlation analysis indicated a strong relationship between zooplankton abundance and physico-chemical parameters. Overall, the physico-chemical profile of Sarangani Bay did not differ from the standards set by DENR, and analysis of the zooplankton communities revealed that Sarangani Bay favorably supports marine organisms to flourish. The findings of this study provide useful knowledge on zooplankton communities and can be used to create management strategies to protect the aquatic biodiversity in Sarangani Bay.Keywords: aquatic biomonitoring, biodiversity, physicochemical analysis, population survey, Sarangani Bay, Sarangani Province, zooplankton
Procedia PDF Downloads 304594 Dynamic Modeling of the Impact of Chlorine on Aquatic Species in Urban Lake Ecosystem
Authors: Zhiqiang Yan, Chen Fan, Yafei Wang, Beicheng Xia
Abstract:
Urban lakes play an invaluable role in urban water systems such as flood control, water supply, and public recreation. However, over 38% of the urban lakes have suffered from severe eutrophication in China. Chlorine that could remarkably inhibit the growth of phytoplankton in eutrophic, has been widely used in the agricultural, aquaculture and industry in the recent past. However, little information has been reported regarding the effects of chlorine on the lake ecosystem, especially on the main aquatic species.To investigate the ecological response of main aquatic species and system stability to chlorine interference in shallow urban lakes, a mini system dynamic model was developed based on the competition and predation of main aquatic species and total phosphorus circulation. The main species of submerged macrophyte, phytoplankton, zooplankton, benthos, spiroggra and total phosphorus in water and sediment were used as variables in the model,while the interference of chlorine on phytoplankton was represented by an exponential attenuation equation. Furthermore, the eco-exergy expressing the development degree of ecosystem was used to quantify the complexity of the shallow urban lake. The model was validated using the data collected in the Lotus Lake in Guangzhoufrom1 October 2015 to 31 January 2016.The correlation coefficient (R), root mean square error-observations standard deviation ratio (RSR) and index of agreement (IOA) were calculated to evaluate accuracy and reliability of the model.The simulated values showed good qualitative agreement with the measured values of all components. The model results showed that chlorine had a notable inhibitory effect on Microcystis aeruginos,Rachionus plicatilis, Diaphanosoma brachyurum Liévin and Mesocyclops leuckarti (Claus).The outbreak of Spiroggra.spp. inhibited the growth of Vallisneria natans (Lour.) Hara, leading to a gradual decrease of eco-exergy and the breakdown of ecosystem internal equilibria. This study gives important insight into using chlorine to achieve eutrophication control and understand mechanism process.Keywords: system dynamic model, urban lake, chlorine, eco-exergy
Procedia PDF Downloads 229593 Effect of Bacillus thuringiensis israelensis against Culex pipiens (Insect: Culicidae) Effect of Bti on Two Non-Target Species Eylais hamata (Acari: Hydrachnidia) and Physa marmorata (Gastropoda: Physidae) and Dosage of Their GST Biomarker
Authors: Meriem Mansouri, Fatiha Bendali Saoudi, Noureddine Soltani
Abstract:
Biological control presents a means of control for the protection of the environment. Bacillus thuringiensis israelensis Berliner 1915 is an inseticide of biological origin because it is a bacterium of the Bacillaceae family. This biocide has a biological importance, because of its specific larvicidal action against Culicidae, blood-sucking insects, responsible for several diseases to humans and animals through the world. As well as, its high specificity for these insects. Also, the freshwater mites, this necessarily parasitic group for aquatic species such as the Physidae, also have an effective biological control against the Culicidae, because of their voracious predation to the larvae of these insects. The present work aims to study the effects of the biocide Bacillus thuringiensis var israelinsis, against non-target adults of water mites Eylais hamata Koenike, 1897, as well as its associated host species Physa marmorata Fitzinger, 1833. After 12 days of oral treatment of adults with lethal concentration (LC50:0.08µg/ml), determined from essays on 4th instar larvae of Culex pipiens (hematophagous insects). No adverse effect has been recorded for adult individuals of Eylais hamata, contrary, snail Physa marmorata were sensitive for this dose of Bti. In parallel, after treatment at the Bti by LC50, the enzyme stress bio marker glutathione S-transferase, was measured after 24, 48 and 72 hours. The enzymatic activity of GST has increased after 24 and 48 hours following treatment.Keywords: biological control, Bacillus thuringiensis var israelinsis, culicidae, hydrachnidia, enzymatic activity
Procedia PDF Downloads 646592 Evaluation of Monoterpenes Induction in Ugni molinae Ecotypes Subjected to a Red Grape Caterpillar (Lepidoptera: Arctiidae) Herbivory
Authors: Manuel Chacon-Fuentes, Leonardo Bardehle, Marcelo Lizama, Claudio Reyes, Andres Quiroz
Abstract:
The insect-plant interaction is a complex process in which the plant is able to release chemical signaling that modifies the behavior of insects. Insect herbivory can trigger mechanisms that allow the increase in the production of secondary metabolites that allow coping against the herbivores. Monoterpenes are a kind of secondary metabolites involved in direct defense acting as repellents of herbivorous or even in indirect defense acting as attractants for insect predators. In addition, an increase of the monoterpenes concentration is an effect commonly associated with the herbivory. Hence, plants subjected to damage by herbivory increase the monoterpenes production in comparison to plants without herbivory. In this framework, co-evolutionary aspects play a fundamental role in the adaptation of the herbivorous to their host and in the counter-adaptive strategies of the plants to avoid the herbivorous. In this context, Ugni molinae 'murtilla' is a native shrub from Chile characterized by its antioxidant activity mainly related to the phenolic compounds presents in its fruits. The larval stage of the red grape caterpillar Chilesia rudis Butler (Lepidoptera: Arctiidae) has been reported as an important defoliator of U. molinae. This insect is native from Chile and probably has been involved in a co-evolutionary process with murtilla. Therefore, we hypothesized that herbivory by the red grape caterpillar increases the emission of monoterpenes in Ugni molinae. Ecotypes 19-1 and 22-1 of murtilla were established and maintained at 25° C in the Laboratorio de Química Ecológica at Universidad de La Frontera. Red grape caterpillars of ⁓40 mm were collected near to Temuco (Chile) from grasses, and they were deprived of food for 24 h before performing the assays. Ten caterpillars were placed on the foliage of the ecotypes 19-1 and 22-1 and allowed to feed during 48 h. After this time, caterpillars were removed from the ecotypes and monoterpenes were collected. A glass chamber was used to enclose the ecotypes and a Porapak-Q column was used to trap the monoterpenes. After 24 h of capturing, columns were desorbed with hexane. Then, samples were injected in a gas chromatograph coupled to mass spectrometer and monoterpenes were determined according to the NIST library. All the experiments were performed in triplicate. Results showed that α-pinene, β-phellandrene, limonene, and 1,8 cineole were the main monoterpenes released by murtilla ecotypes. For the ecotype 19-1, the abundance of α-pinene was significantly higher in plants subjected to herbivory (100%) in relation to control plants (54.58%). Moreover, β-phellandrene and 1,8 cineole were observed only in control plants. For ecotype 22-1, there was no significant difference in monoterpenes abundance. In conclusion, the results suggest a trade-off of β-phellandrene and 1,8 cineole in response to herbivory damage by red grape caterpillar generating an increase in α-pinene abundance.Keywords: Chilesia rudis, gas chromatography, monoterpenes, Ugni molinae
Procedia PDF Downloads 147591 Surface Sterilization of Aquatic Plant, Cryptopcoryne affinis by Using Clorox and Mercury Chloride
Authors: Sridevi Devadas
Abstract:
This study was aimed to examine the combination efficiency of Clorox (5.25% Sodium Hypochlorite) and mercury chloride (HgCl2) as reagent for surface sterilization process of aquatic plant, Cryptocoryne affinis (C. affinis). The treatment applied 10% of the Clorox and 0.1 ppm of mercury chloride. The maximum exposure time for Clorox and mercury chloride was 10 min and 60 sec respectively. After exposed to the treatments protocols (T1-T15) the explants were transferred to culture room under control temperature at 25°C ± 2°C and subjected to 16 hours fluorescence light (2000 lumens) for 30 days. The both sterilizing agents were not applied on control specimens. Upon analysis, the result indicates all of the treatments protocols produced sterile explants at range of minimum 1.5 ± 0.7 (30%) to maximum 5.0 ± 0.0 (100%). Meanwhile, maximum 1.0 ± 0.7 numbers of leaves and 1.4 ± 0.6 numbers of roots have been produced. The optimized exposure time was 0 to 15 min for Clorox and 30 sec for HgCl2 whereby 90% to 100% sterilization was archived at this condition.Keywords: Cryptocoryne affinis, surface sterilization, tissue culture, clorox, mercury chloride
Procedia PDF Downloads 592590 Effects of Large Woody Debris on the Abundance and Diversity of Freshwater Invertebrates and Vertebrates
Authors: M. J. Matulino, Carissa Ganong, Mark Mills, Jazmine Harry
Abstract:
Large Woody Debris (LWD), defined as wooden debris with a diameter of at least 10 cm and a length of 2 m, serves as a crucial resource and habitat for aquatic organisms. While research on the ecological impacts of LWD has been conducted in temperate streams, LWD's influence on tropical stream biodiversity remains understudied, making this investigation particularly valuable for future conservation efforts. The Sura River in La Selva Biological Station includes both LWD and open channel sites. We sampled paired LWD and open-channel sites using minnow traps, Promar traps, and dip nets. Vertebrates were identified as species, while macroinvertebrates were identified to order level. We quantified abundance, richness, and Shannon diversity at each. We captured a total of 467 individuals, including 2 turtles, 17 fishes, 1 freshwater crab, 39 shrimp, and 408 other macroinvertebrates. Total abundance was significantly higher in LWD sites. Species richness was marginally higher in LWD sites, but the Shannon diversity index did not differ significantly with habitat. Shrimp (Macrobrachium olfersi) length was significantly higher in LWD areas. Increased food resources and microhabitat availability could contribute to higher abundance, richness, and organismal size in LWD environments. This study fills a critical gap by investigating LWD effects in a tropical environment, providing valuable insights for conservation efforts and the preservation of aquatic biodiversity.Keywords: large woody debris (LWD), aquatic organisms, ecological impacts, tropical stream biodiversity, conservation efforts
Procedia PDF Downloads 81589 Histological Changes in the Culex pipiens Mosquito Larvae Treated by the Entomopathogenic Fungus Beauveria bassiana
Authors: Fatma Sahir- Halouane, Sonia Hamid, Farida Tihar-Benzina, Fatiha Bouhlali, Souad Lourchane
Abstract:
The Culicidae are biting insects, the most harmful to people, they are almost all bloodsuckers, and they are responsible of the spread of many important diseases such as malaria, yellow fever, and elephantiasis. Entomopathogenic microorganisms occupy an important place among the alternative methods of fighting against pests insect. The fungus Beauveria bassiana is an entomopathogenic agent naturally present in the ecosystems. It offers a very interesting potential for controlling populations of mosquitoes. This study aimed to show the histological changes that occured in Culex pipiens larvae infected with Beauveria bassiana. The 4th instar larvae were infected with B. bassiana in 10-7 spore/ml dilution, the histological section was studied showing that the fungi infected all the body parts specially Cuticle, Epiderms, fat bodies and midgut. After then the insect have a white appearance and covered with a thick coat of hyphea. The obtained results show that the application of Beauveria bassiana on cuticle of the fourth stage larvae of Culex pipiens was dependent of an apparent disturbance on the structure of the cuticle or there has been the degeneration of its different parts, infection of the fungus does not stop at the body walls. Therefore, it affects even the Adipose tissue, epidermal cells and intestine.Keywords: Culex pipiens, Beauveria bassiana, histological changes, cuticle, intestine and adipose tissue
Procedia PDF Downloads 275588 Surface Sterilization Of Aquatic Plant, Cryptocoryne affinis by Using Clorox and Mercury Chloride
Authors: Sridevi Devadas
Abstract:
This study was aimed to examine the combination efficiency of Clorox (5.25% Sodium Hypochlorite) and mercury chloride (HgCl2) as a reagent for surface sterilization process of aquatic plant and cryptocoryne affinis (C. affinis). The treatment applied 10% of the Clorox and 0.1ppm of mercury chloride. The maximum exposure time for clorox and mercury chloride was 10min and 60sec respectively. After exposed to the treatments protocols (T1-T15) the explants were transferred to culture room under control temperature at 25°C ± 2°C and subjected to 16 hours fluorescence light (2000 lumens) for 30 days. The both sterilizing agents were not applied on control specimens. Upon analysis, The result indicates all of the treatments protocols produced sterile explants at range of minimum 1.5 ± 0.7 (30%) to maximum 5.0 ± 0.0 (100%). Meanwhile, maximum 1.0 ± 0.7 numbers of leaves and 1.4 ± 0.6 numbers of roots have been produced. The optimized exposure time was 0 to 15 min for Clorox and 30 sec for HgCl2 whereby 90% to 100% sterilization was archived at this condition.Keywords: Cryptocoryne affinis, surface sterilization, tissue culture, clorox, mercury chloride
Procedia PDF Downloads 375587 Evaluation of a Chitin Synthesis Inhibitor Novaluron in the Shrimp Palaemon Adspersus: Impact on Ecdysteroids and Chitin Contents
Authors: Hinda Berghiche, Hamida Benradia, Noureddine Soltani
Abstract:
Pesticides are widely used in crop production and are known to induce a major contamination of ecosystems especially in aquatic environments. The leaching of a large amount of pollutants derived from agricultural activities (fertilizers, pesticides) might contaminate rivers which diverse into the likes and estuarine and coastal environments affecting several organisms such as crustacean species. In this context, there is searched for new selective insecticides with minimal toxic effects on the environment and human health such as growth insect regulators (GIRs). The current study aimed to examine the impact of novaluron (CE 20%), a potent benzoylphenylurea derivative insecticide on mosquito larvae, against non-target shrimp, Palaemon adspersus (Decapoda, Palaemonidae). The compound was tested at two concentrations (0.91 mg/L and 4.30 mg/L) corresponding respectively to the LC50 and LC90 determined against fourth-instar larvae of Culiseta longiareolata (Diptera, Culicidae). The molting hormone titer was determined in the haemolymph by an enzyme-immunoassay, while chitin was measured in peripheral integument at different stages during the molting cycle. Under normal conditions, the haemolymphatic ecdysteroid concentrations increased during the molting cycle to reach peak at stage D. In the treated series, we note absence of the peak at stage D and an increase at stages B, C and D as compared to the controls. Concerning the chitin amounts, we observe an increase from stage A to stage C followed by a decrease at stage D. Exposition of shrimps to novaluron resulted in a significant decrease of values at all molting stages with a dose-response effect. Thus, the insecticide can present secondary effects on this non-target arthropod species.Keywords: toxicology, novaluron, crustacean, palaemon adspersus, ecdysteroids, cuticle, chitin
Procedia PDF Downloads 246586 Adsorption of Malachite Green Dye onto Industrial Waste Materials: Full Factorial Design
Authors: Semra Çoruh, Yusuf Tibet
Abstract:
Dyes are widely used in industries such as textiles, paper, paints, leather, rubber, plastics, cosmetics, food, and drug etc, to color their products. Due to their chemical structures, dyes are resistant to fading on exposure to light, water and many chemicals and, therefore, are difficult to be decolorized once released into the aquatic environment. Many of the organic dyes are hazardous and may affect aquatic life and even the food chain. This study deals with the adsorption of malachite green dye onto fly ash and red mud. The effects of experimental factors (adsorbent dosage, initial concentration, pH and temperature) on the adsorption process were examined by using 24 full factorial design. The results were statistically analyzed by using the student’s t-test, analysis of variance (ANOVA) and an F-test to define important experimental factors and their levels. A regression model that considers the significant main and interaction effects was suggested. The results showed that initial dye concentration an pH is the most significant factor that affects the removal of malachite green.Keywords: malachite green, adsorption, red mud, fly ash, full factorial design
Procedia PDF Downloads 469