Evaluate the growth capacity of some indigenous tree afforestation models at the center of environmental research in hoa binh province

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY STUDENT THESIS EVALUATE THE GROWTH CAPACITY OF SOME INDIGENOUS TREE AFFORESTATION MODELS AT THE CENTER OF ENVIRONMENTAL RESEARCH IN HOA BINH PROVINCE Major : Natural Resources Management Code : D850101 Faculty : Forest Resources and Environmental Management Student : Dao Duy Duc Student ID : 1453091252 Class : K59A – Natural Resources Management Course : 2014-2018 Advanced Education Program Developed in collaboration with Colorado State University, USA Supervisor: Dr Ha Quang Anh Hanoi, October, 2018 ACKNOWLEDGEMENT To accomplish and complete this thesis, I have received a great deal of support from organizations and individuals First of all, I would like to send my sincere thanks to the School Management Board, teachers in the Forest Resource and Environmental Management Faculty for helping me with my studies and training at the school In particular, I would like to express my deep gratitude to Dr Ha Quang Anh for his great guidance in the process of implementing this thesis Besides, this thesis could not be completed without help of the officers, especially Mr Tran Trung Thanh – director of the Center of Environmental Research Hoa Binh city who helped me in the process of surveying, collecting data and assessing the afforestation situation at the research center Finally, I would like to send my most sincere thanks to my family, relatives and friends who have encouraged and helped me through the process of completing this thesis Although there have been a range of attempts to complete the project, due to the limited time and knowledge, the thesis is inevitable shortcomings So, I hope that I could receive the attention and comments of teachers and friends to complete the course Hanoi, September 1, 2018 Student Dao Duy Duc i TABLE OF CONTENTS ACKNOWLEDGEMENT i TABLE OF CONTENTS ii ABSTRACT vii CHAPTER GENERAL REVIEW OF THE RESEARCH ISSUE I Introduction II GENERAL REVIEW OF THE RESEARCH ISSUE 2.1 In the world 2.1.1 Indigenous plants in the world 2.1.2 Basis researches 2.2 In Vietnam 2.2.1 Indigenous plants in Vietnam 2.2.2 Basis researches 2.2.3 Practical researches CHAPTER OBJECTIVES, CONTENTS, RESEARCH SUBJECT, LIMITS AND RESEARCH METHODS 2.1 Objective 2.2 Contents 2.3 Research subject 2.4 Limits 2.4.1 Place 2.4.2 Time 2.5 Materials and methods 2.5.1 Materials 2.5.2 Methods 13 ii CHAPTER NATURAL, SOCIO-ECONOMIC CONDITIONS OF RESEARCH AREA 18 3.1 Natural conditions 19 3.1.1 Geographical location 19 3.1.2 Topographic 19 3.1.3 Climate 20 3.1.4 Hydrological 20 3.1.5 Geology, soil 21 3.1.6 Forest resources 21 3.2 Social and economic conditions 22 3.2.1 Population, ethnicity and labor 22 3.2.2 Infrastructure 23 CHAPTER RESULTS AND DISCUSSION 24 4.1 Growth criteria 24 4.1.1 Height growth (Hvn) 24 4.1.2 Diameter at breast height – DBH (D1.3) 27 4.1.3 Canopy diameter (Dt) 30 4.2 Trees’ quality 32 4.3 Survival rate 36 4.4 Vegetation cover and shrubs 37 4.4.1 Vegetation cover and shrubs in Acacia mangium model 38 4.4.2 Vegetation cover and shrubs in Acacia auriculiformis model 39 CHAPTER CONCLUSION, DRAWBACKS AND PROPOSAL 41 5.1 5.1.1 Conclusion 41 Some growth criteria 41 iii 5.1.2 Trees’ quality 42 5.1.3 Survival rate 42 5.1.4 Vegetation cover and shrubs 43 5.2 Drawbacks 43 5.3 Proposal 43 REFERENCES APPENDIX iv LIST OF TABLE Table 4.1: Average height growth of the investigated species 24 Table 4.2: Diameter at breast height growth – DBH of the investigated species 27 Table 4.3: Canopy diameter growth of the investigated species 30 Table 4.4: Trees quality in different time period 32 Table 4.5: Average quality of each species in all period 33 Table 4.6: The survival rate of tree species by age 36 Table 4.7: Vegetation cover and shrubs in Acacia mangium model 38 Table 4.8: Vegetation cover and shrubs in Acacia auriculiformis model 39 v LIST OF FIGURES Figure 2.1: Overview of the project approaching method 14 Figure 4.1: Average height (Hvn) among different species 25 Figure 4.2: Annual height increase (Hvn) among different species 26 Figure 4.3: Erythrophleum fordii 26 Figure 4.4: Peltophorum pterocarpum 26 Figure 4.5: Diameter at breast height (∆D1.3) among different species 28 Figure 4.6: Annual DBH (D1.3) increase among different species 29 Figure 4.7: Cinnamomum obtusifolium 29 Figure 4.8: Lithocarpus ducampii 29 Figure 4.9: Canopy diameter (Dt) among different species 31 Figure 4.10: Annual canopy diameter increase (∆Dt) among diferent species 32 Figure 4.11: Quality of each species in different periods 35 Figure 4.12: Quality of each species in all periods 35 Figure 4.13: Survival rate of species at 1-year and 6-years of age in Acacia mangium model 37 Figure 4.14: Forest vegetation and shrubs 40 vi ABSTRACT In recent years, the government has launched programs to promote the reforestation of bare hills and economic forests with relatively good initial effects However, due to the trend of economic development, investment capital is limited Therefore, the plantation programs in our country focus on fast growing species such as Acacia, Eucalyptus and Bodhi These species only meet the economic objectives but not the requirements of protecting the ecological environment due to the low sustainability In the forestry development strategy, forestry has focused on the conservation and development of indigenous tree species Today, it is known that the great benefits that indigenous tree species provide are not merely the provision of specialty forestry products, but also the long-standing evolution of plants should be highly adaptable to the growing conditions and have high sustainability, therefore, planting them would have many benefits For that reason, I undertake this research: “Evaluate the growth capacity of some indigenous tree afforestation models at the center of the environmental research in Hoa Binh province” The research was conducted by examining the area which indigenous trees are planted at the center After preliminary evaluation, two standard sample plots of 500 m2 were established on two different supporting species which are Acacia mangium and Acacia auriculiformis The results illustrate that species in two models grow well under the assistance of supporting plants However, most of the trees Acacia mangium model were better than that of Acacia auriculiformis in terms of diameter growth at breast height (D1.3), height growth (Hvn), canopy diameter (Dt), quality and survival rate After investigating and analyzing the data, some conclusions have been drawn and hopefully they could be used to contribute to the elaboration of the scientific foundations, which shall serve as a basis for proposing solutions for optimizing indigenous trees planting efficiency vii CHAPTER GENERAL REVIEW OF THE RESEARCH ISSUE I Introduction Forest is a precious resource with multiple benefits for community and society Forest is an irreplaceable part of the ecosystem which plays an extremely vital role in human life At present, the government restricts the exploitation of natural forests and many regions have shifted to forest plantation Provinces and enterprises determine the purpose of speeding up the economic afforestation in terms of volume and quantity to meet the demand of goods for society, first of all supplying raw materials for industrial parks and houses machine, Apart from providing timber, firewood and other forest products, forests play a crucial role in protecting and maintaining habitats such as regulating climate, regulating water resources, limiting erosion, mitigating the effects of floods, the absorption of carbon dioxide, the maintenance and conservation of biodiversity Indigenous plants have formed symbiotic relationships with native wildlife over thousands of years, therefore offered the most sustainable habitat for wild animals A species is considered as indigenous if it exists naturally in a particular region, ecosystem, or habitat without human intervention It is challenging for some indigenous plants to adapt to the environment such as harsh climates or special soil conditions Although those plants only exist within a very limited range (endemism), others can live in diverse areas or by adaptation to different surroundings Research has found that insects depend on indigenous plants An alternative but potentially conflicting usage is to describe plants (and animals) that are indigenous to a geographical area, even if they are known to have self-introduced in historical times Indigenous plants help the environment the most when planted in places that match their growing requirements They could thrive in the soils, moisture and weather of your region That means less supplemental watering, which can be wasteful, and pest problems that require toxic chemicals Indigenous plants also assist in managing rain water runoff and maintain healthy soil as their root systems are deep and keep soil from being compacted If planting indigenous species (over 10-years production cycle) instead of other timber trees such as acacia hybrid, the time for the product longer but the value will be larger It is possible to compare the three acacia crops that will take between 23 and 25 years In the meantime, if we invest in the planting of indigenous timber species in Group (common wood for home furniture) Teak, mucilage, hymenoptera , the trees have a diameter of about 20 - 25cm and can be harvested with a stock equal to or greater than the acacia hybrids of 7-8 years old In addition, if the planting of multi-species trees such as pine, black, white fill , the producer will harvest from non-timber forest products for example resin It is higher than that of timber in terms of benefit Thus, in terms of economic growth of large trees, indigenous trees are at least twice as good as acacia hybrid In terms of the area of afforestation of indigenous trees throughout 25 years, the land is continuously covered by vegetation cover and forest canopy; the forest ecosystem is stable; Acacia hybrid plantation forest is interrupted by two mining operations, equivalent to 5-6 years of land without sufficient cover, which not only eroded soil but also affected climate change - Erythrophleum fordii has a relatively high percentage of good trees from 83.3% to 92% The medium trees percentage is from to 10% and the poor trees is from to 13.6% Especially the 0% rate of the poor trees that grown under the canopy of Acacia mangium canopy, so it can be seen that the plants grow well under this condition - Peltophorum pterocarpum has high proportion of good trees, from 73.3% to 85.7% However, the rate of medium and poor trees remained high (up to 23.3% for medium and 14.3% for poor trees) - Lithocarpus ducampii and Cinnamomum obtusifolium are at an average level compared to other species, with very high rate of poor trees in 2016 (26.7%) However, when planted under canopy of Acacia mangium and Acacia auriculiformis, the results are very positive, as evidenced by the fact that the percentage of good trees has increased significantly, the rate of medium trees has dropped to relatively low but the rate of poor trees is still quite high (21.1%) in Acacia auriculiformis model Pest situation: During the collection of data on survival and growth of plant species in the model, the observation showed that the experimental species were infected by some pests such as Limacodidae (for Peltophorum pterocarpum) and Arna pseudoconspersa, Spodoptera exigua and Chelidonium argentatum, but the frequency is small so their impact is not significant In particular, there are some harmful insects such as termites and crickets These are the factors that lead to decreased plant growth and resistance 34 Specific results of each period are shown in the charts below Figure 4.11: Quality of each species in different periods Figure 4.12: Quality of each species in all periods 35 4.3 Survival rate After investigating sample planting models which is with Acacia mangium and Acacia auriculiformis, I found that indigenous plants in Acacia mangium had better growth criteria and quality than that of Acacia auriculiformis Therefore, due to time constraints, I only investigated the survival rate of the species in Acacia mangium model The results survival rate of each species in the Acacia mangium model are summarized in the table below Table 4.6: The survival rate of tree species by age Survival rate by age (%) Age Erythrophleum 94.4 95.2 94.6 93.3 91.1 91.1 88.9 96.7 95.4 94.1 93.3 92.7 67.7 84.2 75.5 73.6 73.6 73.1 82.2 92.7 92.5 91.1 88.9 88.5 82.2 97.2 96.6 96.3 94.4 94.4 fordii Peltophorum pterocarpum Lithocarpus ducampii Cinnamomum obtusifolium Hopea odarata The survey shows that Acacia mangium is now grown as a supporting plant, but due to its rapid growth, this species tends to override the nutrient space of indigenous plants grown under canopy so it has great influences to the growth and development of indigenous plants From data in Table 4.1, it was found that in the first year, indigenous species had a high survival rate, most of which were over 82% Only Lithocarpus ducampii had lower survival rate which is 67.7% 36 Based on the actual survey in December 2009, the current survival rate of all species at the age of was above 73%, the highest survival rate was Hopea odarata at 94.4%, followed by Peltophorum pterocarpum at 92.7%, next is Erythrophleum fordii, Cinnamomum obtusifolium and Lithocarpus ducampii (91.1, 88.5 and 73.1% respectively) Different species with different ecological characteristics will adapt to different habitat conditions, so when they are grown under uniform conditions, there will be a difference in survival rate Survival rate of plant species at the age of and is further illustrated by the diagram below Figure 4.13: Survival rate of species at 1-year and 6-years of age in Acacia mangium model 4.4 Vegetation cover and shrubs The vegetation plays a vital role in the forest community as well as the forest ecosystem In addition to the effect of reducing surface runoff, water retention contributes to limiting erosion and runoff Vegetation also plays a role in providing a great source of organic matter, increasing soil fertility, creating mixed forest species, multiple layer canopy It is also a supportive and competitive factor for plant species Therefore, the study of forest vegetation 37 is important in adjusting and supplementing technical measures to take care of the forest environment 4.4.1 Vegetation cover and shrubs in Acacia mangium model Results of data collection and analyze are summarized in the following table: Table 4.7: Vegetation cover and shrubs in Acacia mangium model Plot Main species Htb (m) Cover (%) Quality 0.66 50 Medium 1.15 80 Good 0.96 70 Good Averrhoa carambola Chromolaena odorata Gleicheniaceae Rhodomyrtus tomentosa Gleicheniaceae Rauwolfia Castanea sativa Breynia tonkinensis Chromolaena odorata Carapichea ipecacuanha Averrhoa carambola Castanea sativa The table shows that the majority of participant vegetation and shrubs including: chromolaena odorata, gleicheniaceae, carapichea ipecacuanha, averrhoa carambola, castanea sativa, Among them, gleicheniaceae and averrhoa carambola are dominant species Gleicheniaceae make good conditions for the development of acacia mangium and indigenous species The average height of shrub is ranging from 0.66m to 1.15 m; land cover of 50 to 70% demonstrates that the site conditions are good for the development of species plantation 38 4.4.2 Vegetation cover and shrubs in Acacia auriculiformis model Results of data collection and analyze are summarized in the following table: Table 4.8: Vegetation cover and shrubs in Acacia auriculiformis model Plot Species Htb (m) Cover (%) Quality 0.57 45 Medium 0.84 60 Medium 0.79 55 Medium Paeonia albiflora Rhodomyrtus tomentosa Rhodomyrtus tomentosa Rhodomyrtus tomentosa Polypodiaceae Bidens pilosa Bidens pilosa Paeonia The composition of the main shrubs includes: bidens pilosa, paeonia, rhodomyrtus tomentosa, ect The growth of shrubs in this area is less developed than that in acacia mangium, the species composition is simpler, the cover percentage is relatively low (from 4560%), the quality is only at average level The vegetation in this area is lower than in acacia mangium, therefore, the growth and quality of indigenous plants in this area is also lower in acacia mangium It can be said that the vegetation cover and shrubs in Acacia mangium model is better than that of Acacia auriculiformis model - In Acacia mangium model: vegetation cover and shrubs account for 50 to 80% and the quality is relatively good - In Acacia auriculiformis model: vegetation cover and shrubs account for 45 to 60% and the quality is medium 39 Figure 4.14: Forest vegetation and shrubs 40 CHAPTER CONCLUSION, DRAWBACKS AND PROPOSAL 5.1 Conclusion From the results of the study, the following conclusions can be drawn: 5.1.1 Some growth criteria 5.1.1.1 Height growth In two models, the height growth rate was quite good, however, it seems trees grown under the condition Acacia mangium model is better than that of Acacia auriculiformis - In Acacia mangium model: the average height (Hvn) of species from to 8.7 m, annual height increase (∆Hvn) from 1.00 to 1.45 m/year - In Acacia auriculiformis model: the average height (Hvn) of species from 5.8 to 7.3 m, annual height increase (∆Hvn) from 0.97 to 1.22 m/year 5.1.1.2 Diameter at breast height In two models, the diameter at breast height (DBH - D1.3) growth rate was quite good, however, it seems trees grown under the condition Acacia mangium model is better than that of Acacia auriculiformis - In Acacia mangium model: the average DBH (D1.3) of species from 6.5 to 9.1 cm, annual DBH increase (∆D1.3) from 1.08 to 1.52 cm/year - In Acacia auriculiformis model: the average DBH (D1.3) of species from 6.3 to 8.8 cm, annual DBH increase (∆D1.3) from 1.05 to 1.47 cm/year 5.1.1.3 Canopy diameter In two models, the canopy diameter (Dt) growth rate was relatively good However, there are some slightly differences between two models 41 - In Acacia mangium model: the average canopy diameter (Dt) of species from 2.5 to 4.2 m, the annual canopy diameter increase (∆Dt) from 0.42 to 0.67 m/year - In Acacia auriculiformis model: the average canopy diamater (Dt) of species from 2.9 to 3.9 m, the annual canopy diameter increase (∆Dt) from 0.48 to 0.65 m/year It is challenging to conclude which species develops better in this case 5.1.2 Trees’ quality Regarding to the quality of species: In general, the quality of good trees (%) in the survey area is the majority and the highest is Erythrophleum fordii and Hopea odarata with the rate of good trees is 87 and 94% respectively, the lowest rate of the good trees is the Cinnamomum obtusifolium which only reach approximately 75% Pest situation: During the collection of data on survival and growth of plant species in the model, the observation showed that the experimental species were infected by some pests such as Limacodidae (for Peltophorum pterocarpum) and Arna pseudoconspersa, Spodoptera exigua and Chelidonium argentatum, but the frequency is small so their impact is not significant 5.1.3 Survival rate Regarding the survival rate: At the age of 6, the survival rate of indigenous species in the Acacia mangium model was quite high - Erythrophleum fordii had survival rates of 91.1 - 95.2% - Peltophorum pterocarpum had survival rate of 88.9 to 96.7% - Cinnamomum obtusifolium had survival rate of 82.2 - 92.7% - Hopea odarata from 82.2 to 97.2% is the species with the highest survival rate - The species with lowest survival rate is Lithocarpus ducampii which only reached 67.7 - 84.2% 42 5.1.4 Vegetation cover and shrubs The vegetation cover and shrubs in Acacia mangium model is better than that of Acacia auriculiformis model - Acacia mangium model: vegetation cover and shrubs account for 50 to 80% and the quality is relatively good - Acacia auriculiformis model: vegetation cover and shrubs account for 45 to 60% and the quality is medium 5.2 Drawbacks About the research content: Owing to the limited time and resources, the research is only focused on some of the most promising native species (5 similar species in each planting models) In this project, the investigation could not be performed on the whole area but only on some sample plots representing the stands (each plot corresponds to a unit of experimental layout) There are some shortcomings in this research because of limited knowledge as well as lacking of independent research experience On the other hand, the topic is the research at the grassroots level, so there is no source for reference 5.3 Proposal After researching the topic, I suggested some recommendations following: About research content: It should have further investigation the relationship between the growth of indigenous trees and some other ecological factors that have not been addressed in the project, such as temperature, slope, humidity, etc About research volume: At the research center, there are 10 indigenous species planted under the canopy of Acacia mangium and 180 species grown under the canopy of Acacia 43 auriculiformis Therefore, further research on the growth and ecological characteristics of the remaining species should be made in order to apply more appropriate technical measures About the topic: due to the lack of equipment to determine the intensity of light, it is impossible to determine the relationship between the growth of indigenous trees with the intensity of light Therefore, it is necessary to increase the equipment and learning tools in order to help students become more active in the learning process in general and to implement the thesis in particular 44 REFERENCES [1] Tran Van Con, 2005 “Đanh gia ket qua rung cay ban dia la rong o Tay Nguyen” Final report of the project, Vietnammese Academy of Forest Sciences [2] Nguyen Ngoc Lung, Vo Dai Hai, 1997.” Ket qua buoc đau nghien cuu tac dung phong ho nguon nuoc cua mot so tham thuc vat chinh cac nguyen tac xay dung rung phong ho dau nguon nuoc” agricultural publisher HCM city -1997 [3] Vo Dai Hai, 2008 “Ket qua thuc hien hoat dong cua hop phan nghien cuu du an RENFODA”, Vietnammese Academy of Forest Sciences [4] Hoang Lien Son and collaborators, 2005 “Đanh gia chat luong rung phong ho dau nguon du an moi treu rung giai doạn 1998 - 2004 va de xuat cac giai phap cho giai doạn 2006 – 2010” Vietnammese Academy of Forest Sciences APPENDIX I Some tables were used during the field-work Growth criteria survey: D1.3(cm) Dt(m) No Hvn(m) ĐT NB Hdc(m) Quality TB Trees’ quality survey: D00 (cm) No Dt (m) Species Quality Hvn(m) ĐT NB Cover ĐT TB ĐT NB Shrubs investigation: Quality Htb No Main species Cover (%) (m) Good Medium Bad Note Vegetation cover investigation: Thickness No Cover (%) (cm) II Some photos taken during the field-work Decomposition level (%) Note ... of the indigenous tree 13 General approaching method Evaluate growth capacity of some indigenous tree afforestation models Measuring a number of growth criteria including Hvn, D1.3, Dt Evaluating... the center of the environmental research in Hoa Binh province? ?? The research was conducted by examining the area which indigenous trees are planted at the center After preliminary evaluation, two... sustainability, therefore, planting them would have many benefits For that reason, I undertake this research: ? ?Evaluate the growth capacity of some indigenous tree afforestation models at the center