Biodiversity and ecological association of tree species in special use forests huong son my duc ha noi

ACKNOWLEDGEMENTS This study was conducted for months with lot of support, guidance and encouragement from teachers, friends and beloved family members as well as relevant institutions Taking this opportunity, I would like to express my thanks to all First of all, I would like to express my great respect and profound gratitude to my supervisor, Prof.Dr Pham Van Dien and co-supervisor, Dr Le Quoc Huy for their lucid and genial guidance, encouragement and hospitality Only with their enthusiastic guidance and encouragement, I was able to accomplish my study successfully as designed I also would like to express sincere thanks to the Management Board, Forest ranger of Huong Son Special Use Forest, local people and especially Vietnam National University of Forest (VNUF) and Research Institute for Forest Ecology and Environment (RIFEE) - Vietnamese Academy of Forest Sciences (VAFS) for kind help and support with regard to study sites, datasets and administrative arrangement for my thesis study Finally, I appreciate my family and classmates who were always by my side, motivate and encourage me Due to time constrains , knowledge and capacity limitation, this study might still have some mistakes, I am really sorry for this inconvenience if any I look forward to the future endeavor with your continuos support and collaboration for my better research work Sincerely Ha Noi October 2nd, 2016 Le Thi Thu Hang ABSTRACT The biodiversity and ecological association of tree species has an important meaning ,tree layer is decisive component of forest ecosystem but it hasn’t earn much attention in our country Therefore, study on diversity and ecological association of them in natural forests takes a very important role for more understanding about this system The study was based on 18 sampling plots (1000 m2/plot), distributed on 06 fields in the special use forests of Huong Son, Ha Noi The paper determined 05 important characteristics concerning the tree communities, including: (i) important value index (IV, %); (ii) species dominance pattern; (iii) species diversity indices; and (iv) assessment of factors affecting the study site (v) ecological association of tree species and proposed some conservation measures and sustainable development The results indicated that, all plots together there are 43 species found to be ecological significance in the communities with their IV higher than 5%, and there are four species found as dominance in three plots with their IV more than 30%, made a geometric steep slope pattern in the top niche of diversity dominance (D-D) curve IV change curve by species sequence showed that, big differentiate among studied fields The value of species diversity indices also showed that, diversity of tree species in the studied sites is at medium level From results of estimating the Site disturbance index (SDI) consider that almost of study site are more or less influenced by human, in which the biggest factors affecting the biological diversity is Agriculture encroachment There were up to 11 couples of tree species found with their similarity of 80% The results showed that 120 tree species found in the studied sites were devided into 04 ecological groups Through this approach, we could infer the relationship among them (independent, mutual, or comparative) Based on results achieved, the present study would be considered as a typically quantitative research on diversity and ecological association of tree species In addition, the paper has its significance for further understanding about tree communities of tropical natural forests in special use forests of Huong Son, Ha Noi TABLE OF CONTENT ACKNOWLEDGEMENTS ABSTRACT TABLE OF CONTENT LIST OF TABLE LIST OF FIGURE INTRODUCTION REVIEW OF LITERATURE 10 RESEARCH GOALS AND OBJECTIVES 15 3.1 Goals 15 3.2 Specific objectives 15 METHODS 18 4.1 Establish the sampling plot 18 4.2 Data collection method 18 4.3 Calculation method 18 4.4 Dominance Diversity curve (D-D) method 20 4.5 Estimating the Site disturbance index (SDI) method 21 4.6 Data analysis method 23 RESEARCH RESULT AND DISCUSSION 24 5.1 Important Value Index (IV%) 24 5.2 Dominance Diversity Curve of trees species in Huong Son SUF 28 5.3 Diversity indices of tree species 34 5.4 Assessment of factors affecting the study site 36 5.4.1 Agriculture encroachment 36 5.4.2 Invasive species 37 5.4.3 Tourism activities 37 5.4.4 Firewood and medicinal collection 38 5.4.5 Logging and fires 38 5.5 Ecological Association of tree species 40 5.6 Proposed some conservation measures and sustainable development 44 5.6.1 Policy and sustainable management of forest resources solutions: 45 CONCLUSION 48 SHORTCOMINGS AND RECOMMENDATION 50 7.1 Shortcomings 50 7.2 Recommendation 50 REFERENCES LIST OF TABLE Table 4.1 Site Disturbance Index - SDI 22 Table 5.1 Importan value index 25 Table 5.2 Diversity Indices of tree species 34 Table 5.3 Site disturbances index definition 39 LIST OF FIGURE Figure 3.1 Map of Huong Son Special Use Forest with sites under the study (source: Huy et al 2008, Cong 2013 17 Figure 5.1 Dominance Diversity Curve of tree species in Gieng Chen 28 Figure 5.2 Dominance Diversity Curve of tree species in Thung Sau 29 Figure 5.3 Dominance Diversity Curve of tree species in Ben Da Rung Vai 29 Figure 5.4 Dominance Diversity Curve of tree species in Hinh Bong 30 Figure 5.5 Dominance Diversity Curve of tree species in Thung Mang 30 Figure 5.6 Dominance Diversity Curve of tree species in Tuyet Son 31 Figure 5.7 Dominance Diversity Curve of all sites together under sutdy in Huong Son SUF 32 Graph 5.1 Ecological Association of tree species in stand 41 Graph 5.2 PCA graph represent for ecological association of tree species 416 Graph 5.3 Branching graph represents the relationship between the secondary plot 43 Graph 5.4 NMDS secondary sampling plot 44 INTRODUCTION Environmental degradation is one of the most serious issues over the world today, it includes deforestation, biodiversity loss, pollution , desertification, climate change, global warming and so on The consequence of environmental degradation can be devastating on the social, economic and environmental values and systems As a cause from the environmental degradation, forests and biodiversity resources are still being declined and lost at all local, regional and global scales Around the world, biological communities that took millions of years to develop are being devastated (Sharma 2003)[1] About 20 per cent of all species are expected to be lost within 30 years and 50 per cent or more by the end of 21st century (Sharma 2004)[2] The current decline in biodiversity is largely the result of human activities, ranging from habitat destruction, over-harvesting, and pollution, to inappropriate introduction of exotic plants and animals The diversity of natural ecological communities has never been more valued than it is now, as it becomes increasingly threatened by the environmental crises Efforts are, therefore, needed to conserve biological resources and utilize them on a sustainable basis, and maintain genes, species and ecosystems (Verma 2000)[3] the signing of the Convention on Biological Diversity by more than 190 countries at the Earth Summit in Rio de Janeiro in 1992 put this subject at the top of international environmental agenda and brought a sense of urgency to the issue of biological conservation Biodiversity is not only fundamental to the quality of human life It is essential for human survival.( Tuxill, J., & Bright,1998)[4] and The future of biodiversity signifies the future of humankind Its pathways to restoration or destruction are for humans to choose By being cognisant, and by being morally alive, humanity can work to save its own body and soul (O’Riordan, T et al 2002)[5] so maintenance of biodiversity in managed forest ecosystem is an increasing concern (Jobidon et al 2004)[6] In 1992, the World Conservation Monitoring Centre evaluated Vietnam as one of the 16 most biologically diverse countries in the world In Viet Nam , biodiversity plays a very important role in the socio-economic and environmental development of Vietnam Through these services, biodiversity makes significant contribution to the national economy, providing a basis for ensuring food security; maintaining genetic resources of animals and plants; and providing materials for construction, fuel and pharmaceutical resources However, Vietnam’s biodiversity is facing many threats (Van Huu Tap , 2015)[7] Ecological association among species is a characteristics of forest vegetation The survival, variation and the distribution of a certain species in space and time depend not only on the physical environment (climate, soil) but also on the mutual relationships between species coexist in the environment In nature, populations or organisms not exsist alone, but they usually coexistence and interaction among each other for their better exsistance and association Mutual interactions among species expressed in many aspects: competition, parasitic, symbiotic, mutualism and so on Plant community is a collection of plant species coexisted on a defined region, is characterized by a combination of species composition, structure, relationships between species with each other and with the environment Features of this reciprocal relationship are established by life forms and ecological characteristics of the plants and also by the characteristics of the habitat that is the characteristic of climate, soil and human impact, animal Biological relationships are extremely complex and diverse, and not always, we would distinguish these relationships together Study about ecological association among species, groups of species, or event among plant communities provide us with valuable information on the partern, the role, the affect each other and impact on natural ecosystems of plant species As part of the SUF system in Vietnam, the Huong Son SUF is an important natural reserve for biodiversity, landscape and curtural conservation as well as local livelihoods However, the forests and biodiversity there are currently affected negatively by both human activities and natural incidents and degradations Therefore, the conservation of biodiversity, protection of precious gene pool as well as other natural resources are concerned There were already some itnitial research on forest enventories and assessment for values, significances and potentials of the protected area, however, a number of important issues has not been done systematically and scientifically with regard to vegetation and biodiversity partern examination, biodiversity and vegetation quantification, their valuation and so on, those would be the important basis for knowledge and understanding, for later application studies and soluation development, as well as other issues of decision makers for its sustainable management and utilization All together, there is an urgent need to carry out studies to understand biodiversity and ecological association We should find its uses and conservation, planning and management for concept of sustainable management and development In view of the situation and requirements, the study” Biodiversity and Ecological Association of tree species in special use Forests Huong son, My Duc, Ha Noi “ was formulated to conduct This present study as a topical issue, would meet the gap of requirement and would contribute well for the development of measures and solution as mentioned above REVIEW OF LITERATURE Biodiversity conservation Vietnam is one of the most biodiversity rich countries in the world, comprising only 1% of the earth’s surface but being home to 10% of all species Nevertheless, many threats to biodiversity in Vietnam that are existing Being introduced in 1992, the Convention of Biological Diversity (CBD) is considered as a principal comittment of signed state members to conserve and utilise the world biodiversity in a sustainable way and to equally share benefits provided by this resurce The Strategy has been released, serving as a basic orientation for the long-term development of forest resources in Vietnam In 1995, the first National Biodiversity Action Plan (NBAP) of Vietnam that was approved by Prime Minister This plan has become a legal document that directed biodiversity conservation activities in Vietnam (report to the biodiversity convention secretariat) Ingeneral, Vietnam has been acknowledged as a country with high biodiversity, and as one of the prioritized nations for global conservation so need to national biodiversity strategies and section plans for biodiversity conservation and sustainable management Biodiversity measurement and quantification Research biodiversity and the biodiversity of the areas of study that has long been the world's scientists particularly interested, so has a lot of studies have been published Biodiversity attracted the interest of all communities and the scientists by the need to learn and its importance to human beings Biodiversity attracted the interest of all communities and the scientists by the need to learn and its importance to human beings Regarding quantitative biodiversity research The diversity of species in tropical rainforests is expressed by the formula ShannonWeiner (1971) as a parameter to compare the density of each species with H = 6.0 (6.2 = 97% maximum) is greater than 10 times temperate broadleaf forests (0.6) This index decreases from the tropics to two poles, and depends on different continents In the result of research 10 PCA result also reflected the relationship among species and between species with No 6, 7, 9, 11 and 14, etc plots were independent of each other This indicated that there were few species occur in other plots after appeared in these plots In other words, the relationship among the species in this group was weak and had little meaning Another important issue arised was that are secondary plots identical to each other? In other words, are the secondary plots’ specific characteristics the same or different? To answer this question, the study used multiple criteria, including: Diversity Indices of tree species ( indices) and some other characteristics The result was shown in graph 5-3 Graph 5.3 Branching graph represents the relationship between the secondary plot With similarity level below 60%, all plots were a population When the similarity level increased, the plots also fragmented and "separated" out With the similarity level of 90-96%, some plot groups were close together, meaning that their characteristics were similar, their species occured simultaneously According to graph 5-3, plots with close relationship were: with 3, with 7, 11 with 12, 14 with 16, etc 43 However, if the similarity level was 97% or more there would be no couple This suggested that uniformity in this area is difficult to achieve Divergence among sample plots was also evidenced in graph 5-4 The NMDS result showed that the discrete among plots was clear Stress index used in this case was S = 0.13, at a very good level for reducing the Dimention while maintaining the accuracy needed Graph 5.4 NMDS secondary sampling plot 5.6 Proposed some conservation measures and sustainable development The main purpose of conservation effort is to maintain a high diversity of forest ecosystems Researchers have identified the diversity and ecological relationships of woody plants in Huong Son mountainouse area Researches and field surveys showed that the impact of several factors such as: tourism, crop restructuring and cultivation, overexploitation of forest resources, etc., to the diversity and ecological relationships in the region From these findings, we propose a number of measures for the conservation of diversity and ecological relationships in Huong Son SUF as follows: 44 5.6.1 Policy and sustainable management of forest resources solutions: In Huong Son, there are currently no appropriate development - investment policy in accordance with natural and cultural components, as well as no long-term strategic orientation for development - investment stages and for the specific development objectives set for each stage Therefore, investment and development is temporary, fragmented, focus mainly on the ones that can return benefit immediately Here, there are overlaps, gaps in management and use of natural resources, biological resources and culture Currently, many stakeholders are related to development management, exploitation and use of natural resources and local culture, such as the Huong Son special-use forest management board, Huong Son resort management board, Huong Son commune people's Committee, other private entities are exploiting, cultivating on land of the historical site and the SUF No division of consistent and synchronization management responsibilities between the stakeholders, leading to shortcomings in management and long-term orientation, arbitrary in utilization and creating negative impact on the environment, depleting natural resources, biological resources and cultural landscapes Application regulations and effective enforcement of legal protection of natural resources, water resources, biodiversity, wildlife is not high, the cultivated farming practices, logging, exploitation, hunting , animal trapping, electric fishing Solutions: - Establish clear boundaries for SUF, create investment projects of socio-economic development through conservation activities to attract both domestic and international organizations and individuals to participate in the investment of the conservation area, which is the basis to create jobs and increase income for people and Nature Reserve’s staff, creating a solid buffer steps for all effective conservation activities - There should be a reasonable development priority investment policy with longterm orientation, at many different levels, such as municipal, national or regional level 45 - Development-investment policy for sustainable management and development of natural resources, cultural landscapes, associated with economic, culture and tourism development goals of the city, in order to improve the historical site of Huong Son, My Duc, Hanoi to a new national and regional level - Strategic plan developed through stages - In parallel with the development-investment plans, there is a need to clearly define the functions, duties & rights, participation and coordination of the activities of all stakeholders, reviewing the entire land use situation in the region, combining the benefits between community livelihood development through sustainable cultivation of traditional crops with protection and sustainable development of forest resources, biological diversity resource and ecological community tourism - Need to adopt tougher and more active measures to enhance the effective enforcement of laws that protect natural resources Issue applicable taxes for tourism business activities, especially need to closely monitor the travel business, encourage environmental friendliness tourism, ecological community tourism, cultural community tourism, in order to encourage and entice the community to participate actively in the process of protecting natural resources, biodiversity and ecology 5.6.2 Solutions to improve the public awareness and the development of participation approaches in conservation and sustainable development of biodiversity The issue of conservation and sustainable development of biodiversity in Huong Son SUF of people in the region is limited, many people are standing by, and even cause negative impacts to forest resources, water resources, flora and fauna and the Huong Son's landscapehistorical site The perception of the people is not high on the importance and role of natural resources, forest resources and biodiversity, as well as understanding how to effectively incorporate sustainable benefits ensuring the conservation and management of well-developed natural resources, biodiversity, landscapes, but still ensures the sustainable and stable benefits 46 Besides, there are no measures, reasonable policies here to encourage active participation of citizens in the process of conservation and sustainable development of natural resources The involvement approach methods in the development of conservation of natural resources, biodiversity, ecotourism community has not been set to apply Solutions - Improving the management capacity of the State in the field of forest protection and management for local forest protection staff - Building capacity for local government authorities, other agencies and organizations involved in the protection and development of forests, biodiversity conservation, through training courses, seminars, the propaganda - Propagating universal basic knowledge about the importance and role of natural resources, biodiversity, problems and methods of conservation and development, the concept of conservation and sustainable development to the people - Developing and promulgating appropriate regulations, policies to encourage local community to participate actively in the process of protection, management and sustainable development of natural resources, forests resources and biodiversity 47 CONCLUSION (i) Biodiversity of tree species in the study site is at medium level (represented by S, d, H' and D indices) From the sites under present study, there are 43 tree species out of 120 tree species as total with their IV of 5% or more, (taking 35.8 %) those are considered to be sufficiently and ecologically significant to join the forest stands in the community From the results of D-D curve analysis of the present study it would be concluded that the D-D curves of Thung sau, Thung Mang and Tuyet Son suggests a geometric series with a steep slope for dominant species with high IV values of more than 30 % in the top of the D-D Niche Space While at Gieng Chen and Ben Da-Rung Vai sites, the D-D curve strongly suggests a lognormal series in the much richer community with less dominance and a very gradual shift from high to the lowest IV species in the D-D consequence For all sites of the present study, the Shannon’s Diversity Index (H’) ranges from 1.66 to 2.90 (Table 2) The highest values of H’ are found in Gieng Chen site (2.90; 2.70, and 2.30), where its D-D curve recorded with lognormal series, less dominance, a gradual shift from the high to the lowest IV species in the D-D sequency, followed by H’ of Ben da – Rung vai site (2.06; 2.19; 2.01) While the lowest H’ values are found in Thung Sau and Hinh Bong sites, where their D-D curves recorded with geometric series, steep slope with high dominant species (IVs of 30 % or more) Site Disturbance Index - SDI index ranged from 0.30 to 0.6 Almost of study site are more or less influenced by human, in which the biggest factors affecting the biological diversity is Agriculture encroachment Gieng Chen is least influenced and Thung Mang is most influenced (ii) The study used tools such as branching diagrams, PCA graph, NMDS graph to simulate the ecological relationship among tree species in the forest, as well as to assess the gathering of secondary plots in the population based on the different characteristics of the 48 forest vegetation In general, the level of similarity was 97 % or higher, pairs of trees with close relationship with each other was rare Also at this level of similarity, uniformity of natural forests on the characteristics of the vegetation is not achieved 49 SHORTCOMINGS AND RECOMMENDATION 7.1 Shortcomings In the framework of the study, because there are many restrictions on the scale of time and scope of research, study subjects rated only concentrated in the typical area, without farreaching analysis and evaluate the whole system of Huong Son SUF biodiversity resources, no analysis and comprehensive assessment of the value of biodiversity, no update of the Latin names of all species appear in the sample plots, nor reach deeper in assessing environmental values and environmental services However, the biodiversity resources of the SUF Huong Son and their large role is undeniable, to contribute to the conservation of natural resources, biodiversity and promote values for people in the region and the community, regulators and policy makers should base on the assessment findings, learning of extensive strategic and implementation of appropriate solutions in order to bring practical results 7.2 Recommendation - Investment policies for recovery and development, with high biological diversity and endangered species in the Red Book of Vietnam in Huong Son SUF are needed - Research and application of management model with the participation of the people, the activities that have impacts on forest must be scientific-based, exploition and using of natural resources must be sustainable - Need deep study of woody plants: current population status, distribution, utilization levels as a basis for developing scientific solutions for sustainable management of forest resources on limestone forest in general and Huong Son SUF in particular - Analyze the variation of diversity of woody plants under the impact of local people 50 REFERENCES [1] Sharma, P D 2003 Ecology and environment 7th edition Rastogi Publication, New Delhi [2] Sharma, P 2004 Floristic dynamics and distribution pattern of woody plants in Kinnaur Dr Y.S Parmar University of Horticulture and Forestry, Solan (HP), India [3] Verma, R K 2000 Analysis of species diversity and soil quality under Tectona grandis L.f and Acacia catechu (L.f.) 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