scholarly journals Conservation water environment of a lagoon system by controlling manure distribution

Author(s):  
Déthié Dione ◽  
Mouhamadou Dosso ◽  
Saliou Diouf ◽  
Bakary Kone ◽  
Paul Python Ndekou
2020 ◽  
Vol 20 (3) ◽  
pp. 325-332
Author(s):  
Le Nhu Da ◽  
Le Thi Phuong Quynh ◽  
Phung Thi Xuan Binh ◽  
Duong Thi Thuy ◽  
Trinh Hoai Thu ◽  
...  

Recently, the Asian rivers have faced the strong reduction of riverine total suspended solids (TSS) flux due to numerous dam/reservoir impoundment. The Red river system is a typical example of the Southeast Asian rivers that has been strongly impacted by reservoir impoundment in both China and Vietnam, especially in the recent period. It is known that the reduction in total suspended solids may lead to the decrease of some associated elements, including nutrients (N, P, Si) which may affect coastal ecosystems. In this paper, we establish the empirical relationship between total suspended solids and total phosphorus concentrations in water environment of the Red river in its downstream section from Hanoi city to the Ba Lat estuary based on the sampling campaigns conducted in the dry and wet seasons in 2017, 2018 and 2019. The results show a clear relationship with significant coefficient between total suspended solids and total phosphorus in the downstream Red river. It is expressed by a simple equation y = 0.0226x0.3867 where x and y stand for total suspended solids and total phosphorus concentrations (mg/l) respectively with the r2 value of 0.757. This equation enables a reasonable prediction of total phosphorus concentrations of the downstream Red river when the observed data of total suspended solids concentrations are available. Thus, this work opens up the way for further studies on the calculation of the total phosphorus over longer timescales using daily available total suspended solids values.


Author(s):  
Sima Ajdar qizi Askerova

Monitoring of sea water condition is one of major requirements for carrying out the reliable ecological control of water environment. Monitoring networks contain such elements as sea buoys, beacons, etc. and are designated for measuringvarious hydrophysical parameters, including salinity of sea water. Development of specialized network and a separate buoy system for measuring thesea water salinity at different depths makes it possible to determine major regularities of processes of pollution and self-recovery of the sea waters. The article describes the scientific and methodological basics for development of this specialized network and questions of its optimal construction. It is well-known that at a depth of 30-45 m of the Caspian Sea salinity decreases and then at a depth of 45-60 m salinity is fully recovered. The mentioned changes of salinity at the relatively upper layer of sea waters is of special interest for studying the effect of ocean-going processes on the climate forming in the Caspian area. In terms of informativeness of measurements of surface waters salinity, the most informative is a layer ata 30-60 m depth, where inversion and recovery of salinity take place. It is shown that in most informative subrange of measurements, i. e. at a depth of 30-60 m optimization of regime of measurements complex should be carried out in order to increase the effectiveness of held researches. It is shown that at a depth of 35-50 m choice of the optimum regime of measurements makes it possible to obtain the maximum amount of information.


Author(s):  
Võ Văn Phú

TÓM TẮT Đầm phá Tam Giang - Cầu Hai thuộc vào hệ đầm phá lớn nhất Đông Nam Á với diện tích 22.000 ha, đặc trưng cho vùng nhiệt đới gió mùa. Hệ đầm phá là vùng có giá trị về đa dạng sinh học, sinh thái và môi trường. Từ 08/2014 đến 07/2015 chúng tôi đã tiến hành thu thập vật mẫu, nghiên cứu và đã xác định được 24 loài động vật hai mảnh vỏ thuộc 19 giống, 11 họ, 7 bộ. Bổ sung thêm 6 loài thuộc 6 giống, 5 họ mới so với nghiên cứu trước đây. Đánh giá được đặc điểm phân bố về thành phần loài, mật độ cá thể động vật hai mảnh vỏ theo ba loại nền đáy (cát bùn, bùn cát và giá thể) và ba nhóm loài theo độ mặn (loài nước ngot, nước lợ và nước mặn). Abstract Tam Giang - Cau Hai lagoon is the largest in Southeast Asia. It is ​​22,000 hectares. Lagoon system is high of biodiversity, ecology and environment. According to a researcher from August 2014 to July 2015, we have identified 24 species of 19 genera of 11 families of 7 orders of bivalve (Bivalvia) to be living in Tam Giang - Cau Hai lagoon. The result added 6 new species of 6 genera of 5 orders compared with previous studies. We have appreciated distribution characteristics of species composition, density of individual animals bivalve in three categories substrata (silt, sand and substrate ) and three groups of species under salinity (species of freshwater, brackish and saltwater).


2011 ◽  
Vol 10 (6) ◽  
pp. 849-853 ◽  
Author(s):  
Guisen Du ◽  
Huimin Li ◽  
Yumei Wu ◽  
Dianwei Wu ◽  
Jingshi Wang

Author(s):  
Adi Mora Lubis ◽  
Nelly Astuti Hasibuan ◽  
Imam Saputra

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through a specific software. In the water environment, the light factor greatly influences the results of the quality of the image obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. . uneven lighting and bluish tones. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of repairing digital images that experience interference in lighting. The lighting repair process uses homomorphic filtering and uses contrast striching and will compare the quality of both methods and test to prove the results of image quality between homomorphic filtering and contrast streching. Until later the results of both methods can be seen which is better. homomorphic filtering and contrast stretching can produce image improvements with pretty good performance.Keywords: Digital Image, Underwater Image, Homomorphic Filtering, Contrast Streching, Matlab R2010a


Author(s):  
Bainun Harahap

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through certain software devices. In the water environment, light factors greatly influence the results of image quality obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. Underwater imagery is widely used as an object in various activities such as underwater habitat mapping, underwater environment monitoring, underwater object search. Uneven lighting and colors that tend to be bluish and runny. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of improvement in digital images that experience interference in lighting and exposure to sunlight. The lighting repair process uses the retinex method and will compare the quality of the two methods later. Until later the results of both methods can be seen which is better. Retinex method can produce image improvement with high performance.Keywords: Digital Cintra, Underwater, Matlab Retinex Method


2013 ◽  
Vol 8 (2) ◽  
pp. 159-178 ◽  

Atrazine, a chlorinated s-triazine group of herbicide is one of the most widely used pesticides in the World. Due to its extensive use, long half-life and various toxic properties, it has very high environmental significance. Up to 22 mg l-1 of atrazine was found in ground water whereas permissible limit of atrazine is in ppb level in drinking water. As per Indian standard there should not be any pesticide present in drinking water. Among many other treatment processes available, Incineration, adsorption, chemical treatment, phytoremediation and biodegradation are the most commonly used ones. Biological degradation of atrazine depends upon various factors like the operating environment, external carbon and nitrogen sources, carbon/ nitrogen ratio (C/N), water content and the bacterial strain. Although, general atrazine degradation pathways are available, the specific pathways in specific conditions are not yet clearly defined. In this paper extensive review has been made on the occurrence of atrazine in surface and ground water bodies, probable sources and causes of its occurrence in water environment, the toxicity of atrazine on various living organisms and its removal by biological processes.


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