Current Status of Mangrove Forests in the Trans-boundary Sundarbans

Author(s):  
R. N. Mandal ◽  
Peter Saenger ◽  
Chandan Surabhi Das ◽  
Abdul Aziz
Author(s):  
Nguyen Thi Hong Mai ◽  
Nguyen Quang Tan ◽  
Nguyen Hoang Khanh Linh

Abstract: While mangrove forests support large surrounding populations and diverse economic activities, mangrove areas in Central Vietnam are decreasing. This study, thereforce, aims to understand the current status and threats facing mangrove conservation and development. A survey of 52 respondents was conducted in Duy Xuyen district, the largest area of mangrove forests of Quang Nam province. The results show that 17 mangrove species belong to 11 families, in which 8 significant species and 9 minor species were found in this site. The distribution of species was uneven with dominated by Nipah palms (Nypafruticans Wurmb). Although the mangrove species had several useful functions including protection against wind, wave break and serving tourism development, mangrove areas have been decreasing from 26.39ha to 18.22ha during period of 1999-2018. In which, 67.3% of respondents argued that the conversion of mangroves to aquaculture is one of the main causes of mangrove loss. The study also provided some suggestions related to a long-term development strategy for both government and local community, especially who are directly involving in the mangrove for their livelihoods.Keywords: Central Vietnam, development strategy, mangrove forests, livelihoods


2019 ◽  
Vol 99 (06) ◽  
pp. 1247-1252
Author(s):  
Madoka Ohji ◽  
Hiroya Harino ◽  
Ken-ichi Hayashizaki ◽  
Koji Inoue ◽  
Fatimah Md. Yusoff ◽  
...  

AbstractTo elucidate the details of both the current status of contamination and the accumulation of organotin compounds (OTs) in mangroves in coastal ecosystems, we determined the concentrations of butyltin compounds (BTs) and phenyltin compounds (PTs) in sediment and mangrove leaves collected from mangrove forests in Merambong and Tinggi Island, Malaysia. Butyltins were detected in all sediment samples collected from both regions, whereas PTs were not detected. The levels of tributyltin (TBT) compounds in the sediment samples were lower than those from previous studies conducted in Malaysia and at other sites in South-east Asia. In both Merambong and Tinggi Island, the average proportions of dibutyltin (DBT) and monobutyltin (MBT), which are degradation products of TBT, were ~70%. This result suggests that the input of TBT has decreased in Malaysia. The proportions of DBT and MBT in the sediment from Merambong were higher than those from Tinggi Island. The concentrations of TBT in mangrove leaves from Tinggi Island were significantly higher than those from Merambong. MBT was the most dominant type among the BTs in mangrove leaves from both Merambong and Tinggi Island. The ratios of the BTs burden in mangrove leaves to the BTs concentration in sediment from Merambong and Tinggi Island averaged 3.1 and 6.2, respectively. Among the values of BTs, the MBT values were found to be the highest in both regions.


2021 ◽  
Vol 41 ◽  
pp. 101573
Author(s):  
S. Sreelekshmi ◽  
Bijeesh Kozhikkodan Veettil ◽  
S. Bijoy Nandan ◽  
M. Harikrishnan

Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1623 ◽  
Author(s):  
Fatin Samara ◽  
Nadia Solovieva ◽  
Thouraya Ghalayini ◽  
Zaina Anwar Nasrallah ◽  
Maria Saburova

In the Arabian Gulf, mangroves play a particularly important role in maintaining biodiversity. Water and intertidal sediments were collected from eight sampling locations in April 2017 to assess the environmental status of the mangrove forest in the Khor al Beida, Umm Al Quwain, which is one of the largest natural mangrove forests in the United Arab Emirates (UAE). Khor al Beida is also a breeding ground for the largest Gulf colony of a regionally endemic Socotra cormorant. Total metal concentrations of water and sediments were measured using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and ranged between 0.001–2.873 mg/L and 0.08–12683.02 mg/kg, respectively. Most metals were within permissible levels, except for copper, iron, aluminum, zinc, and nickel. Hazard Quotient calculations showed low risk to the ecosystem in relation to the presence of heavy metals, with the exception of zinc. Fifty-three diatom species of pennate benthic forms were identified in the intertidal sediments. For the first time in the UAE, diatom composition and diatom diversity values were quantitatively estimated in the surface sediments and a short sediment core. Overall, the assessment suggests that the mangrove forest is currently undisturbed and shows very little anthropogenic impact; yet, protection and conservation efforts are necessary in order to maintain its current status.


2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Nguyen-Thanh Son ◽  
Chi-Farn Chen ◽  
Cheng-Ru Chen

AbstractMangrove forests provide a wide range of socioeconomic and ecological services for coastal communities. Extensive aquaculture development of mangrove waters in many developing countries has constantly ignored services of mangrove ecosystems, leading to unintended environmental consequences. Monitoring the current status and distribution of mangrove forests is deemed important for evaluating forest management strategies. This study aims to delineate the density distribution of mangrove forests in the Gulf of Fonseca, Central America with Rapideye data using the support vector machines (SVM). The data collected in 2012 for density classification of mangrove forests were processed based on four different band combination schemes: scheme-1 (bands 1–3, 5 excluding the red-edge band 4), scheme-2 (bands 1–5), scheme-3 (bands 1–3, 5 incorporating with the normalized difference vegetation index, NDVI), and scheme-4 (bands 1–3, 5 incorporating with the normalized difference red-edge index, NDRI). We also hypothesized if the obvious contribution of Rapideye red-edge band could improve the classification results. Three main steps of data processing were employed:


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
MARY WANJIRU WARUI ◽  
SHYAM MANOHAR ◽  
PAUL OBADE

Abstract. Warui MW, Manohar S, Obade P. 2020. Current status, utilization, succession and zonation of mangrove ecosystem along Mida Creek, Coast Province, Kenya. Bonorowo Wetlands 10: 32-43. Human activities have resulted in the destruction of mangrove forests, posing a threat to the mangrove ecosystem and the living things that rely on it. From September 2009 through February 2010, researchers studied the current state, usage, succession, and zonation of the mangrove ecosystem along Mida Creek in Kenya's Coast Province. The goals were to assess changes in the floristic composition of the mangrove forest, identify the most preferred mangrove species, investigate whether accessibility determines utilization of mangrove species, investigate whether harvesting of mangroves affects their succession, and investigate the effectiveness of current mangrove forest management policies. The data was collected using the Point-Centered Quarter Method (PCQM) to see if access into the mangrove forest influences their use and if mangrove succession is affected by their use. To evaluate the efficiency of government policies/legislation governing mangrove exploitation and the most favored mangrove species by the local community and other users, questionnaires were circulated and interviews were conducted. Out of the 210 houses in Mida Creek, 136 respondents were interviewed, one from each household. To examine the temporal changes in the floristic composition of the mangrove forest, two sets of aerial images (1992 and 2006) were processed and interpreted. The data from the questionnaires were coded and entered into the Statistical Package for the Social Sciences (SPSS). An analysis of variance (ANOVA) was used to see if the accessibility of mangroves influences their use. To see if the utilization of mangroves affects their succession, researchers used regression analysis. To evaluate the forest structure, an importance value was derived. To summarize the present mangrove forest management policies and their effectiveness, descriptive statistics were used. Between 1992 and 2006, the floristic composition of the mangrove forest in Mida Creek changed; the area covered by mangroves decreased as follows: Rhizophora mucronata (Rm); 65.09-63.93ha; Avicennia marina (Am); 344.99-310.63ha; Ceriops tagal (Ct); 225.12-223.82ha; Rm and Ct; 52.87-50.22ha; Ct and Am; 143.69- 140.29ha; Rm and Am; 44.36-41.27ha; Rm and Bg; 212.75-199.75ha; Rm and Sonneratia alba (Sa); 47.64-46.32ha; Rm, Ct and Bruguiera gymnorrhiza (Bg); 129.07-128.12ha; Rm, Am, Ct, and Bg; 472.44-428.46ha. The number of cut mangroves in the adjacent settlements, center, and shoreline revealed a significant difference (F=3.277; df=2; p=0.040) in the ANOVA test, indicating that accessibility determines consumption. The most favored mangrove species was Rhizophora mucronata, according to the findings. There was a correlation between the number of mangrove seedlings and the number of cut mangroves (F=8.529, df=1, R=0.198, P=0.004), according to regression analysis. The use of mangroves has an impact on their succession. Mangrove utilization policies and legislation have been less effective. The key species in Mida Creek were Rhizophora mucronata and Ceriops tagal. The extent of mangrove forests in Mida Creek has shrunk over time.  


1966 ◽  
Vol 25 ◽  
pp. 266-267
Author(s):  
R. L. Duncombe

An examination of some specialized lunar and planetary ephemerides has revealed inconsistencies in the adopted planetary masses, the presence of non-gravitational terms, and some outright numerical errors. They should be considered of temporary usefulness only, subject to subsequent amendment as required for the interpretation of observational data.


Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.


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