Bacterial density in treatments 2 and 3 was statistically significantly higher than treatment 1 and control from day 10 onwards, which showed that in treatments with added bacteria, the time for bacterial density increase was shortened. This also means that bacteria will quickly play a role in converting organic matter from harmful to beneficial forms.
Some studies by Degrange and Bardin (1995); Huang et al (1989); Balmelle et al (1992) cited by Pham Thi Tuyet Ngan and Nguyen Huu Hiep (2010) showed that the density of nitrifying bacteria in nature is relatively low (from 10 1 - 10 3 CFU/g sludge) and the growth of this group of bacteria is limited by environmental factors such as high NH 3 and pH concentrations; low dissolved oxygen and nitrite, low temperature. In addition, these groups are also limited in development by light intensity and duration.
Maybe you are interested!
-
Identify Rating Levels and Rating Scales
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zt2a3gstourism,quan lan,quang ninh,ecology,ecotourism,minh chau,van don,geography,geographical basis,tourism development,science
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of the islanders. Therefore, this indicator will be divided into two sub-indicators:
a1. Natural tourism attractiveness a2. Cultural tourism attractiveness
b. Tourist capacity
The two island communes in Quan Lan have different capacities to receive tourists. Minh Chau Commune is home to many standard hotels and resorts, attracting high-income domestic and international tourists. Meanwhile, Quan Lan Commune has many motels mainly built and operated by local people, so the scale and quality are not high, and will be suitable for ordinary tourists such as students.
c. Time of exploitation of Quan Lan Island Commune:
Quan Lan tourism is seasonal due to weather and climate conditions and festivals only take place on certain days of the year, specifically in spring. In Quan Lan commune, the period from April to June and from September to November is considered the best time to visit Quan Lan because the cultural tourism activities are mainly associated with festivals taking place during this time.
Minh Chau island commune:
Tourism exploitation time is all year round, because this is a place with a number of tourist attractions with diverse ecosystems such as Bai Tu Long National Park Research Center, Tram forest, Turtle Laying Beach, so besides coming to the beach for tourism and vacation in the summer, Minh Chau will attract research groups to come for tourism combined with research at other times of the year.
d. Sustainability
The sustainability of ecotourism sites in Quan Lan and Minh Chau communes depends on the sensitivity of the ecosystems to climate changes.
landscape. In general, these tourist destinations have a fairly high level of sustainability, because they are natural ecosystems, planned and protected. However, if a large number of tourists gather at certain times, it can exceed the carrying capacity and affect the sustainability of the environment (polluted beaches, damaged trees, animals moving away from their habitats, etc.), then the sustainability of the above ecosystems (natural ecosystems, human ecosystems) will also be affected and become less sustainable.
e. Location and accessibility
Both island communes have ports to take tourists to visit from Van Don wharf:
- Quan Lan – Van Don traffic route:
Phuc Thinh – Viet Anh high-speed boat and Quang Minh high-speed boat, depart at 8am and 2pm from Van Don to Quan Lan, and at 7am and 1pm from Quan Lan to Van Don. There are also wooden boats departing at 7am and 1pm.
- Van Don - Minh Chau traffic route:
Chung Huong high-speed train, Minh Chau train, morning 7:30 and afternoon 13:30 from Van Don to Minh Chau, morning 6:30 and afternoon 13:00 from Minh Chau to Van Don.
f. Infrastructure
Despite receiving investment attention, the issue of infrastructure and technical facilities for tourism on Quan Lan Island is still an issue that needs to be resolved because it has a direct impact on the implementation of ecotourism activities. The minimum conditions for serving tourists such as accommodation, electricity, water, communication, especially medical services, and security work need to be given top priority. Ecotourism spots in Minh Chau commune are assessed to have better infrastructure and technical facilities for tourism because there are quite complete and synchronous conditions for serving tourists, meeting many needs of domestic and foreign tourists.
3.2.1.4. Determine assessment levels and assessment scales
Corresponding to the levels of each criterion, the index is the score of those levels in the order of 4, 3, 2, 1 decreasing according to the standard of each level: very attractive (4), attractive (3), average (2), less attractive (1).
3.2.1.5. Determining the coefficients of the criteria
For the assessment of DLST in the two communes of Quan Lan and Minh Chau islands, the students added evaluation coefficients to show the importance of the criteria and indicators as follows:
Coefficient 3 with criteria: Attractiveness, Exploitation time. These are the 2 most important criteria for attracting tourists to tourism in general and eco-tourism in particular, so they have the highest coefficient.
Coefficient 2 with criteria: Capacity, Infrastructure, Location and accessibility . Because the assessment area is an island commune of Van Don district, the above criteria are selected by the author with appropriate coefficients at the average level.
Coefficient 1 with criteria: Sustainability. Quan Lan has natural and human-made ecotourism sites, with high biodiversity and little impact from local human factors. Most of the ecotourism sites are still wild, so they are highly sustainable.
3.2.1.6. Results of DLST assessment on Quan Lan island
a. Assessment of the potential for natural tourism development
For Minh Chau commune:
+ Natural tourism attractiveness is determined to be very attractive (4 points) and the most important coefficient (coefficient 3), so the score of the Attractiveness criterion is 4 x 3 = 12.
+ Capacity is determined as average (2 points) and the coefficient is quite important (coefficient 2), then the score of Capacity criterion is 2 x 2 = 4.
+ Exploitation time is long (4 points), the most important coefficient (coefficient 3) so the score of the Exploitation time criterion is 4 x 3 = 12.
+ Sustainability is determined as sustainable (4 points), the important coefficient is the average coefficient (coefficient 1), so the score of the Sustainability criterion is 4 x 1 = 4 points
+ Location and accessibility are determined to be quite favorable (2 points), the coefficient is quite important (coefficient 2), the criterion score is 2 x 2 = 4 points.
+ Infrastructure is assessed as good (3 points), the coefficient is quite important (coefficient 2), then the score of the Infrastructure criterion is 3 x 2 = 6 points.
The total score for evaluating DLST in Minh Chau commune according to 6 evaluation criteria is determined as: 12 + 4 + 12 + 4 + 4 + 6 = 42 points
Similar assessment for Quan Lan commune, we have the following table:
Table 3.3: Assessment of the potential for natural ecotourism development in Quan Lan and Minh Chau communes
Attractiveness of self-tourismof course
Capacity
Mining time
Sustainability
Location and accessibility
Infrastructure
Result
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
CommuneMinh Chau
12
12
4
8
12
12
4
4
4
8
6
8
42/52
Quan CommuneLan
6
12
6
8
9
12
4
4
4
8
4
8
33/52
b. Assessment of the potential for humanistic tourism development
For Quan Lan commune:
+ The attractiveness of human tourism is determined to be very attractive (4 points) and the most important coefficient (coefficient 3), so the score of the Attractiveness criterion is 4 x 3 = 12.
+ Capacity is determined to be large (3 points) and the coefficient is quite important (coefficient 2), then the score of the Capacity criterion is 3 x 2 = 6.
+ Mining time is average (3 points), the most important coefficient (coefficient 3) so the score of the Mining time criterion is 3 x 3 = 9.
+ Sustainability is determined as sustainable (4 points), the important coefficient is the average coefficient (coefficient 1), so the score of the Sustainability criterion is 4 x 1 = 4 points.
+ Location and accessibility are determined to be quite favorable (2 points), the coefficient is quite important (coefficient 2), the criterion score is 2 x 2 = 4 points.
+ Infrastructure is rated as average (2 points), the coefficient is quite important (coefficient 2), then the score of the Infrastructure criterion is 2 x 2 = 4 points.
The total score for evaluating DLST in Quan Lan commune according to 6 evaluation criteria is determined as: 12 + 6 + 6 + 4 + 4 + 4 = 36 points.
Similar assessment with Minh Chau commune we have the following table:
Table 3.4: Assessment of the potential for developing humanistic eco-tourism in Quan Lan and Minh Chau communes
Attractiveness of human tourismliterature
Capacity
Mining time
Sustainability
Location and accessibility
Infrastructure
Result
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Point
DarkMulti
Quan CommuneLan
12
12
6
8
9
12
4
4
4
8
4
8
39/52
Minh CommuneChau
6
12
4
8
12
12
4
4
4
8
6
8
36/52
Basically, both Minh Chau and Quan Lan localities have quite favorable conditions for developing ecotourism. However, Quan Lan commune has more advantages to develop ecotourism in a humanistic direction, because this is an area with many famous historical relics such as Quan Lan Communal House, Quan Lan Pagoda, Temple worshiping the hero Tran Khanh Du, ... along with local festivals held annually such as the wind praying ceremony (March 15), Quan Lan festival (June 10-19); due to its location near the port and long exploitation time, the beaches in Quan Lan commune (especially Quan Lan beach) are no longer hygienic and clean to ensure the needs of tourists coming to relax and swim; this is also an area with many beautiful landscapes such as Got Beo wind pass, Ong Phong head, Voi Voi cave, but the ability to access these places is still very limited (dirt hill road, lots of gravel and rocks), especially during rainy and windy times; In addition, other natural resources such as mangrove forests and sea worms have not been really exploited for tourism purposes and ecotourism development. On the contrary, Minh Chau commune has more advantages in developing ecotourism in the direction of natural tourism, this is an area with diverse ecosystems such as at Rua De Beach, Bai Tu Long National Park Conservation Center...; Minh Chau beach is highly appreciated for its natural beauty and cleanliness, ranked in the top ten most beautiful beaches in Vietnam; Minh Chau commune is also home to Tram forest with a large area and a purity of up to 90%, suitable for building bridges through the forest (a very effective type of natural ecotourism currently applied by many countries) for tourists to sightsee, as well as for the purpose of studying and researching.
Figure 3.1: Thenmala Forest Bridge (India) Source: https://www.thenmalaecotourism.com/(August 21, 2019)
3.2.2. Using SWOT matrix to evaluate Quan Lan island tourism
General assessment of current tourism activities of Quan Lan island is shown through the following SWOT matrix:
Table 3.5: SWOT matrix evaluating tourism activities on Quan Lan island
Internal agent
Strengths- There is a lot of potential for tourism development, especially natural ecotourism and humanistic ecotourism.- The unskilled labor force is relatively abundant.- resource environmentunpolluted, still
Weaknesses- Poorly developed infrastructure, especially traffic routes to tourist destinations on the island.- The team of professional staff is still weak.- Tourism products in general
quite wild, originalintact
general and DLST in particularalone is monotonous.
External agents
Opportunity- Tourism is a key industry in the socio-economic development strategy of the province and Van Don economic zone.- Quan Lan was selected as a pilot area for eco-tourism development within the framework of the green growth project between Quang Ninh province and the Japanese organization JICA.- The flow of tourists and especially ecotourism in the world tends toincreasing
Challenge- Weather and climate change abnormally.- Competition in tourism products is increasingly fierce, especially with other localities in the province such as Ha Long, Mong Cai...- Awareness of tourists, especially domestic tourists, about ecotourism and nature conservation is not high.
Through summary analysis using SWOT matrix we see that:
To exploit strengths and take advantage of opportunities, it is necessary to:
- Diversify products and service types (build more tourism routes aimed at specific needs of tourists: experiential tourism immersed in nature, spiritual cultural tourism...)
- Effective exploitation of resources and differentiated products (natural resources and human resources)
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Solutions for tourism development in Tien Lang - 10
zt2i3t4l5ee
zt2a3gstourism, tourism development
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- District People's Committees and authorities of communes with tourist attractions should support, promote, and provide necessary information to people, helping them improve their knowledge about tourism. Raise tourism awareness for local people.
*
* *
Due to limited knowledge and research time, the thesis inevitably has shortcomings. Therefore, I look forward to receiving guidance from teachers, experts as well as your comments to make the thesis more complete.
Chapter III Conclusion
Through the issues presented in Chapter II, we can come to some conclusions:
Based on the strengths of available tourism resources, the types of tourism in Tien Lang that need to be promoted in the coming time are sightseeing and resort tourism, discovery tourism, weekend tourism. To improve the quality and diversify tourism products, Tien Lang district needs to combine with local cultural tourism resources, at the same time combine with surrounding areas, build rich tourism products. The strengths of Tien Lang tourism are eco-tourism and cultural tourism, so developing Tien Lang tourism must always go hand in hand with restoring and preserving types of cultural tourism resources. Some necessary measures to support and improve the efficiency of exploiting tourism resources in Tien Lang are: strengthening the construction of technical facilities and labor force serving tourism, actively promoting and advertising tourism, and expanding forms of capital mobilization for tourism development.
CONCLUDE
I Conclusion
1. Based on the results achieved within the framework of the thesis's needs, some basic conclusions can be drawn as follows:
Tien Lang is a locality with great potential for tourism development. The relatively abundant cultural tourism resources and ecological tourism resources have great appeal to tourists. Based on this potential, Tien Lang can build a unique tourism industry that is competitive enough with other localities within Hai Phong city and neighboring areas.
In recent years, the exploitation of the advantages of resources to develop tourism and build tourist routes in Tien Lang has not been commensurate with the available potential. In terms of quantity, many resource objects have not been brought into the purpose of tourism development. In terms of time, the regular service time has not been extended to attract more visitors. Infrastructure and technical facilities are still weak. The labor force is still thin and weak in terms of expertise. Tourism programs and routes have not been organized properly, the exploitation content is still monotonous, so it has not attracted many visitors. Although resources have not been mobilized much for tourism development, they are facing the risk of destruction and degradation.
2. Based on the results of investigation, analysis, synthesis, evaluation and selective absorption of research results of related topics, the thesis has proposed a number of necessary solutions to improve the efficiency of exploiting tourism resources in Tien Lang such as: promoting the restoration and conservation of tourism resources, focusing on investment and key exploitation of ecotourism resources, strengthening the construction of infrastructure and tourism workforce. Expanding forms of capital mobilization. In addition, the thesis has built a number of tourist routes of Hai Phong in which Tien Lang tourism resources play an important role.
Exploiting Tien Lang tourism resources for tourism development is currently facing many difficulties. The above measures, if applied synchronously, will likely bring new prospects for the local tourism industry, contributing to making Tien Lang tourism an important economic sector in the district's economic structure.
REFERENCES
1. Nhuan Ha, Trinh Minh Hien, Tran Phuong, Hai Phong - Historical and cultural relics, Hai Phong Publishing House, 1993
2. Hai Phong City History Council, Hai Phong Gazetteer, Hai Phong Publishing House, 1990.
3. Hai Phong City History Council, History of Tien Lang District Party Committee, Hai Phong Publishing House, 1990.
4. Hai Phong City History Council, University of Social Sciences and Humanities, VNU, Hai Phong Place Names Encyclopedia, Hai Phong Publishing House. 2001.
5. Law on Cultural Heritage and documents guiding its implementation, National Political Publishing House, Hanoi, 2003.
6. Tran Duc Thanh, Lecture on Tourism Geography, Faculty of Tourism, University of Social Sciences and Humanities, VNU, 2006
7. Hai Phong Center for Social Sciences and Humanities, Some typical cultural heritages of Hai Phong, Hai Phong Publishing House, 2001
8. Nguyen Ngoc Thao (editor-in-chief, Tourism Geography, Hai Phong Publishing House, two volumes (2001-2002)
9. Nguyen Minh Tue and group of authors, Hai Phong Tourism Geography, Ho Chi Minh City Publishing House, 1997.
10. Nguyen Thanh Son, Hai Phong Tourism Territory Organization, Associate Doctoral Thesis in Geological Geography, Hanoi, 1996.
11. Decision No. 2033/QD – UB on detailed planning of Tien Lang town, Hai Phong city until 2020.
12. Department of Culture, Information, Hai Phong Museum, Hai Phong relics
- National ranked scenic spot, Hai Phong Publishing House, 2005. 13. Tien Lang District People's Committee, Economic Development Planning -
Culture - Society of Tien Lang district to 2010.
14.Website www.HaiPhong.gov.vn
APPENDIX 1
List of national ranked monuments
STT
Name of the monument
Number, year of decisiondetermine
Location
1
Gam Temple
938 VH/QĐ04/08/1992
Cam Khe Village- Toan Thang commune
2
Doc Hau Temple
9381 VH/QĐ04/08/1992
Doc Hau Village –Toan Thang commune
3
Cuu Doi Communal House
3207 VH/QĐDecember 30, 1991
Zone II of townTien Lang
4
Ha Dai Temple
938 VH/QĐ04/08/1992
Ha Dai Village –Tien Thanh commune
APPENDIX II
STT
Name of the monument
Number, year of decision
Location
1
Phu Ke Pagoda Temple
178/QD-UBJanuary 28, 2005
Zone 1 - townTien Lang
2
Trung Lang Temple
178/QD-UBJanuary 28, 2005
Zone 4 – townTien Lang
3
Bao Khanh Pagoda
1900/QD-UBAugust 24, 2006
Nam Tu Village -Kien Thiet commune
4
Bach Da Pagoda
1792/QD-UB11/11/2002
Hung Thang Commune
5
Ngoc Dong Temple
177/QD-UBNovember 27, 2005
Tien Thanh Commune
6
Tomb of Minister TSNhu Van Lan
2848/QD-UBSeptember 19, 2003
Nam Tu Village -Kien Thiet commune
7
Canh Son Stone Temple
2160/QD-UBSeptember 19, 2003
Van Doi Commune –Doan Lap
8
Meiji Temple
2259/QD-UBSeptember 19, 2002
Toan Thang Commune
9
Tien Doi Noi Temple
477/QD-UBSeptember 19, 2005
Doan Lap Commune
10
Tu Doi Temple
177/QD-UBJanuary 28, 2005
Doan Lap Commune
11
Duyen Lao Temple
177/QD-UBJanuary 28, 2005
Tien Minh Commune
12
Dinh Xuan Uc Pagoda
177/QD-UBJanuary 28, 2005
Bac Hung Commune
13
Chu Khe Pagoda
177/QD-UBJanuary 28, 2005
Hung Thang Commune
14
Dong Dinh
2848/QD-UBNovember 21, 2002
Vinh Quang Commune
15
President's Memorial HouseTon Duc Thang
177/QD-UBJanuary 28, 2005
NT Quy Cao
Ha Dai Temple
Ben Vua Temple
Tien Lang hot spring
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Solutions to improve the quality of consumer lending activities at Vietnam Prosperity Joint Stock Commercial Bank - 2 -
Evaluation Results of Quality Indicators and Importance of Each Indicator -
Current situation and solutions to improve the quality of room service at Habana Hotel - 2
Part V
CONCLUSION AND SUGGESTIONS
5.1 Conclusion
- Bacillus bacteria added to the black tiger shrimp rearing system at a density of 10 5 - 10 6 CFU/mL showed better organic decomposition ability than the density of 10 4 CFU/mL and no bacteria added, moreover, Bacillus bacteria have the ability to inhibit the growth of Vibrio bacteria .
- The density of Nitrosomonas and Nitrobacter bacteria in the experiments with added bacteria was relatively stable. The density of these two groups of bacteria in the recirculating system was about 10 times higher than in the water exchange system.
- The survival rate of larvae in the treatments supplemented with bacteria was higher than that of the control, in which NT2 and NT3 (10 5 and 10 6 CFU/mL Bacillus ) were higher and statistically different (p<0.05) compared to the other two treatments. Shrimp reared in the recirculating system had a higher survival rate (PL7 reached 61.1%) than in the water exchange system (PL7 reached 50.1%).
- In experiment 3, COD index in treatments 2 and 3 was statistically lower than treatment 1 and control, while TAN and NO 3 - were statistically higher (p<0.05).
- Vibrio bacteria density in the treatments supplemented with bacteria was statistically significantly lower than in the control treatment.
- Thus, NT2 (10% filter tank volume ratio, bacteria added) showed higher nitrogen conversion efficiency than NT1 and DC but took up less space and cost than NT3.
5.2 Recommendations
Useful bacteria strains such as Bacillus, Nitrosomonas, Nitrobacter should be added to the black tiger shrimp rearing system to improve water quality, shorten the biological filtration operation time, increase the survival rate of larvae, reduce the use of environmental treatment chemicals and antibiotics that have negative effects on the quality of shrimp larvae.
REFERENCES
Aleem, MIH and M. Alexander. 1960. Nutrition and physiology of Nitrobacter agilis . Laboratory of Soil Microbiology, Department of Agronomy, Cornell University, Ithaca, New York.
Austin, B., L.F. Stuckey, PAW Robertson, J. Effendi and DRW Griffith. 1995. A probiotic reducing disease caused by Aeromonas salmonnicida , Vibrio anguillarium and Vibrio ordalii . Journal of Fish Disease, 18: 93-96.
Baticados, MCL, CR Lavilla-Pitogo, ER Cruz-Lacierda, LD de la Pena and
NA Sunaz. 1990. Studies on the chemical control of luminous bacteria Vibrio harveyi and V. splendidus isolated from diseased Penaeus monodon larvae and rearing water. Diseases of Aquatic Organisms, 9: 133-139.
Belgium. 1999. Improved performance of an intensive rotifer culture system by using a nitrifying inoculum (ABIL).
Boyd, C.E. and C.S. Tucker. 1998. Pond Aquaculture Water Quality Management. Kluwer Academic Publishing, Boston, MA, USA. 700pp.
Brigg, MRP, and Funge-Smith, CS 1994. A nutrient budget of some intensive marine ponds in Thailand. Aquaculture Fisheries Management 24, 789 - 811
Bruno, Gomez-Gil, Ana Roque and James F. Turnbull. 2000. The use and selection of probiotic bacteria for use in the culture of larval aquatic organisms. Aquaculture 191, 259-270
Bui Dac Thuyet. 2004. Wastewater treatment from intensive shrimp ponds: biological solutions and research directions. Research Institute for Aquaculture III.
Chanratchakool, P., J.F. Turnbull, S.J. Funge – Smith, I.H. Macrae and C. Limsuwan. 2003. Shrimp health management in ponds. 4th edition. Translators: Nguyen Anh Tuan, Nguyen Thanh Phuong, Dang Thi Hoang Oanh, Tran Ngoc Hai. Danida – Ministry of Fisheries 2003. 153 pages.
Chau Tai Tao. 2005. Research on the application of maturation and larval rearing of black tiger shrimp ( P. monodon ). Master's thesis - Faculty of Aquaculture - Can Tho University.
Chen JC and Chin, TC 1988. Acute toxicity of nitrite to tiger prawn, Penaeus monodon larvae. Aquaculture 69. 253 – 262.
Degrange V. and R. Bardin. 1995. Detection and Counting of Nitrobacter population in soil by PCR. Applied and Environmental Microbiology, June 1995, 2093 – 2098.
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