Medicinal plants are still used for healthcare and as medicaments especially in developing countries and some rural areas. The potential and high expectation of medicinal plants for local healthcare and livelihood and as biodiversity management is prevalent globally. This study assesses the extent to which medicinal plants bring benefits in biodiversity management and improve livelihood and healthcare in indigenous villages near a small city, a second tier city in the central Peruvian Amazon, taking into consideration the course of urbanization. A total of 81 people living in two villages were interviewed. The results show that unlike areas surrounding large cities in the Amazon, areas around the second tier city do not have the conditions to commercialize medicinal plants to support livelihood. Therefore, the local utilization of medicinal plants does not deteriorate the forest resources, thus medicinal plants would not be expected to be a driver for biodiversity management. Although medicinal plants still support healthcare of the locals, the reliance on modern medicine is aparent. The distance to the urbanized city and modern facilities influences the use of medicinal plants. While close proximity facilitates the use of modern medicine, it is found that mal-accessibility to modern medicine does not increase the variety of medicinal plant use.
{"title":"Assessing medicinal plants as the linkage between healthcare, livelihood and biodiversity: a case study from native villages surrounding a second-tier city in the central Peruvian Amazon","authors":"M. Toda, E. Salgado, M. Masuda","doi":"10.3759/TROPICS.MS15-07","DOIUrl":"https://doi.org/10.3759/TROPICS.MS15-07","url":null,"abstract":"Medicinal plants are still used for healthcare and as medicaments especially in developing countries and some rural areas. The potential and high expectation of medicinal plants for local healthcare and livelihood and as biodiversity management is prevalent globally. This study assesses the extent to which medicinal plants bring benefits in biodiversity management and improve livelihood and healthcare in indigenous villages near a small city, a second tier city in the central Peruvian Amazon, taking into consideration the course of urbanization. A total of 81 people living in two villages were interviewed. The results show that unlike areas surrounding large cities in the Amazon, areas around the second tier city do not have the conditions to commercialize medicinal plants to support livelihood. Therefore, the local utilization of medicinal plants does not deteriorate the forest resources, thus medicinal plants would not be expected to be a driver for biodiversity management. Although medicinal plants still support healthcare of the locals, the reliance on modern medicine is aparent. The distance to the urbanized city and modern facilities influences the use of medicinal plants. While close proximity facilitates the use of modern medicine, it is found that mal-accessibility to modern medicine does not increase the variety of medicinal plant use.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.MS15-07","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70009940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Yoneda, H. Mizunaga, Yoshihiko Uchimura-Tashiro, K. Niiyama, Tamotsu Sato, Y. Kosugi, S. Takanashi, M. Tani, T. Okuda, W. R. Kadir, A. Kassim
Inter-annual variability of net ecosystem productivity (NEP) was assessed by a biometric method observing dynamics of coarse woody organs in a primeval lowland tropical rain forest in Pasoh, Peninsular Malaysia. Yearly changes of NEP estimated by biometric method well agreed with those measured by Eddy Covariance Method (ECM), when we observed a stand within a distance of 125-150 m from the tower for ECM. Annual NEP at a 2-ha stand ranged from -5.0 t Carbon ha y to 2.1 t Carbon ha y during the last 43 years (1969-2012) with two times depressions. They were caused by man-made and natural disturbances that affected as much as 10% of the 2-ha stand area, and negative NEP was maintained during around 10 years after disturbances. Inter-annual variances of NEP, biomass and necromass of coarse woody debris were evaluated by a mathematical simulation with observed properties of net primary productivity and a death rate of coarse woody organs. Simulated NEP was 0.00 ±1.52 t C ha y under equilibrium regimes, and the variance increased under the conditions of a higher mean death rate leading to decrease of biomass. Basing on variances of NEP, we estimated a turnover time of an equilibrium system at 400 years for a 2-ha stand, which is equivalent to 800 ha in area.
采用生物计量学方法，对马来西亚半岛帕索原始低地热带雨林粗木本器官动态变化进行了评价。生物特征法估算的NEP年际变化与涡动相关法(Eddy Covariance method, ECM)测量的NEP年际变化基本一致。近43 a (1969-2012) 2 ha林分年NEP在-5.0 ~ 2.1 t碳当量之间，有2次低洼期。它们是由人为和自然干扰造成的，这些干扰影响了高达10%的2公顷林分面积，并且在干扰后约10年内保持负NEP。利用观察到的净初级生产力和粗木本器官死亡率的特性，通过数学模拟评估了NEP、生物量和粗木本残体坏死质量的年际变化。在平衡状态下，模拟NEP为0.00±1.52 t C / y，在平均死亡率较高导致生物量减少的情况下，方差增大。基于NEP的变化，我们估计一个2 ha林分(相当于800 ha面积)平衡系统的周转期为400年。
{"title":"Inter-annual variations of net ecosystem productivity of a primeval tropical forest basing on a biometric method with a long-term data in Pasoh, Peninsular Malaysia","authors":"T. Yoneda, H. Mizunaga, Yoshihiko Uchimura-Tashiro, K. Niiyama, Tamotsu Sato, Y. Kosugi, S. Takanashi, M. Tani, T. Okuda, W. R. Kadir, A. Kassim","doi":"10.3759/TROPICS.25.1","DOIUrl":"https://doi.org/10.3759/TROPICS.25.1","url":null,"abstract":"Inter-annual variability of net ecosystem productivity (NEP) was assessed by a biometric method observing dynamics of coarse woody organs in a primeval lowland tropical rain forest in Pasoh, Peninsular Malaysia. Yearly changes of NEP estimated by biometric method well agreed with those measured by Eddy Covariance Method (ECM), when we observed a stand within a distance of 125-150 m from the tower for ECM. Annual NEP at a 2-ha stand ranged from -5.0 t Carbon ha y to 2.1 t Carbon ha y during the last 43 years (1969-2012) with two times depressions. They were caused by man-made and natural disturbances that affected as much as 10% of the 2-ha stand area, and negative NEP was maintained during around 10 years after disturbances. Inter-annual variances of NEP, biomass and necromass of coarse woody debris were evaluated by a mathematical simulation with observed properties of net primary productivity and a death rate of coarse woody organs. Simulated NEP was 0.00 ±1.52 t C ha y under equilibrium regimes, and the variance increased under the conditions of a higher mean death rate leading to decrease of biomass. Basing on variances of NEP, we estimated a turnover time of an equilibrium system at 400 years for a 2-ha stand, which is equivalent to 800 ha in area.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.25.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70003109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
REDD ＋ in developing countries needs to estimate forest carbon stocks and above ground biomass. Remote sensing has been widely used for monitoring of vegetated area using the satellite-derived vegetation index since vegetation indices are thought to have high correlation with above ground biomass or vigor of vegetation. However, these satellite-derived vegetation indices are still doubtful whether they are available for REDD ＋ in any types of forests such as forests with different species. We studied the relationship between wood volume data obtained by field survey and the time series of MODIS EVI data to check whether the above ground biomass in different forests with different species could be accurately estimated from satellite remotely sensed data. This paper presents the different correlation for different forests. Our analysis illustrated the correlation between annual wood volume and annual average EVI using a simple linear regression. The regression equation for Forest 1 was Y ＝ 249.02x ＋ 37.474; R 2 ＝ 0.82; N ＝ 22 and for Forest 2 was Y ＝ 668.3x-258.61; R 2 ＝ 0.80; N ＝ 15, and R 2 ＝ 0.0285; N ＝ 15 for forest 3 which mixed more than 7 species, respectively. These different correlations are strongly correlated with composition of species in different forests. The forests with a few tree species had high correlations, while the forest mixed with many species of trees had low correlation. The composition of tree species in forests is an important characteristic for estimating above ground biomass of forests using remote sensing data.
{"title":"Correlation analysis between Enhance Vegetation Index and Wood Volume in Thua Thien Hue Province, Vietnam","authors":"T. Pham, K. Yoshino, T. Nguyen","doi":"10.3759/TROPICS.24.181","DOIUrl":"https://doi.org/10.3759/TROPICS.24.181","url":null,"abstract":"REDD ＋ in developing countries needs to estimate forest carbon stocks and above ground biomass. Remote sensing has been widely used for monitoring of vegetated area using the satellite-derived vegetation index since vegetation indices are thought to have high correlation with above ground biomass or vigor of vegetation. However, these satellite-derived vegetation indices are still doubtful whether they are available for REDD ＋ in any types of forests such as forests with different species. We studied the relationship between wood volume data obtained by field survey and the time series of MODIS EVI data to check whether the above ground biomass in different forests with different species could be accurately estimated from satellite remotely sensed data. This paper presents the different correlation for different forests. Our analysis illustrated the correlation between annual wood volume and annual average EVI using a simple linear regression. The regression equation for Forest 1 was Y ＝ 249.02x ＋ 37.474; R 2 ＝ 0.82; N ＝ 22 and for Forest 2 was Y ＝ 668.3x-258.61; R 2 ＝ 0.80; N ＝ 15, and R 2 ＝ 0.0285; N ＝ 15 for forest 3 which mixed more than 7 species, respectively. These different correlations are strongly correlated with composition of species in different forests. The forests with a few tree species had high correlations, while the forest mixed with many species of trees had low correlation. The composition of tree species in forests is an important characteristic for estimating above ground biomass of forests using remote sensing data.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.24.181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Aiso, F. Ishiguri, Tatsuya Toyoizumi, J. Ohshima, K. Iizuka, D. Priadi, S. Yokota
The anatomical, chemical, and physical characteristics of tension wood were investigated in the commercially important tropical fast-growing plantation species Falcataria moluccana and Acacia auriculiformis. In both cases, pots containing seedlings of the two species were tilted at 50° from a vertical position to promote tension wood formation. During this period, upward bending occurred in the seedlings of both the species. Samples were collected from three different stem positions (lower position, middle position, and upper position). A distinct gelatinous (G-) layer was observed at the lower position in F. moluccana, and lower and middle positions in A. auriculiformis. Compared to normal wood, the anatomical and chemical characteristics, except for the vessel frequency, were significantly different at the lower position in F. moluccana, and at the lower and middle positions in A. auriculiformis, pointing to “typical” tension wood in the inclined stems of both species. Compared to normal wood, the basic density significantly increased at the lower position in F. moluccana, but not in A. auriculiformis. Although a common inclination method was used, the position of the G-layer differed between the two species, suggesting that the degree of response to the inclination stimulus varies among species.
{"title":"Anatomical, chemical, and physical characteristics of tension wood in two tropical fast-growing species, Falcataria moluccana and Acacia auriculiformis","authors":"H. Aiso, F. Ishiguri, Tatsuya Toyoizumi, J. Ohshima, K. Iizuka, D. Priadi, S. Yokota","doi":"10.3759/TROPICS.25.33","DOIUrl":"https://doi.org/10.3759/TROPICS.25.33","url":null,"abstract":"The anatomical, chemical, and physical characteristics of tension wood were investigated in the commercially important tropical fast-growing plantation species Falcataria moluccana and Acacia auriculiformis. In both cases, pots containing seedlings of the two species were tilted at 50° from a vertical position to promote tension wood formation. During this period, upward bending occurred in the seedlings of both the species. Samples were collected from three different stem positions (lower position, middle position, and upper position). A distinct gelatinous (G-) layer was observed at the lower position in F. moluccana, and lower and middle positions in A. auriculiformis. Compared to normal wood, the anatomical and chemical characteristics, except for the vessel frequency, were significantly different at the lower position in F. moluccana, and at the lower and middle positions in A. auriculiformis, pointing to “typical” tension wood in the inclined stems of both species. Compared to normal wood, the basic density significantly increased at the lower position in F. moluccana, but not in A. auriculiformis. Although a common inclination method was used, the position of the G-layer differed between the two species, suggesting that the degree of response to the inclination stimulus varies among species.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.25.33","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research examined mangrove management in Hai Phong city, Vietnam. A combination of logistic regression model data and field survey data were used to investigate the driving forces of mangrove changes. The results indicate that implementation of mangrove management investigated by the authorities, community or local people has affected mangrove change. The main driving force of mangrove loss is over expansion of shrimp aquaculture. The poorer families would like to participate in mangrove conservation activities more than richer households. Mangrove rehabilitation programs have been successfully managed by community-based forest management in cooperation with local authorities in some coastal communes. Nevertheless, the failure to convert shrimp culture from mangrove forest is recognized in other communities. These communes have to replant mangrove in abandoned shrimp ponds and follow the mangrove management used in former communes.
{"title":"Impacts of mangrove management systems on mangrove changes in the Northern Coast of Vietnam","authors":"T. Pham, K. Yoshino","doi":"10.3759/TROPICS.24.141","DOIUrl":"https://doi.org/10.3759/TROPICS.24.141","url":null,"abstract":"This research examined mangrove management in Hai Phong city, Vietnam. A combination of logistic regression model data and field survey data were used to investigate the driving forces of mangrove changes. The results indicate that implementation of mangrove management investigated by the authorities, community or local people has affected mangrove change. The main driving force of mangrove loss is over expansion of shrimp aquaculture. The poorer families would like to participate in mangrove conservation activities more than richer households. Mangrove rehabilitation programs have been successfully managed by community-based forest management in cooperation with local authorities in some coastal communes. Nevertheless, the failure to convert shrimp culture from mangrove forest is recognized in other communities. These communes have to replant mangrove in abandoned shrimp ponds and follow the mangrove management used in former communes.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.24.141","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study aimed to discover the status of several types of forest and based on the opportunity costs of REDD+ to identify which greenhouse gas (GHG) emission mitigation options can be implemented in different forest types in Ba Be National Park, Vietnam. From 1990 to 2000, forest in the study area faced a high rate of forest cover loss and degradation. During the next decade from 2000 to 2010, total forest cover increased gradually. However, the natural forest area still decreased. In our household survey (n=103), respondents reported that main drivers of deforestation and forest degradation in those areas were timber extraction for commercial or subsistence purposes, shifting cultivation, inadequate forest management, bribes to forest rangers, felling trees for firewood and bamboo shoots, and conversion to Mo (Manglietia conifera) and other perennial plants. There are some differences in those drivers between the three villages surveyed. From 2000 to 2010, several land use changes such as the conversion of poor timber forest into recovered timber forest, medium timber forest into poor timber forest and planted forest into bare land with scattered trees caused more than 8,000 tCO2e emissions per year. In regard to opportunity costs, most of the avoidance options have negative opportunity costs, which mean potential benefits. Within the current carbon market price, the avoidance can be applied to reduce approximately 7,900 tCO2e emissions (about 98% reduction) per year in the three communes surveyed.
{"title":"Status of forest development and opportunity cost of avoiding forest conversion in Ba Be National Park, Vietnam","authors":"T. Nguyen, M. Masuda, S. Iwanaga","doi":"10.3759/TROPICS.24.153","DOIUrl":"https://doi.org/10.3759/TROPICS.24.153","url":null,"abstract":"This study aimed to discover the status of several types of forest and based on the opportunity costs of REDD+ to identify which greenhouse gas (GHG) emission mitigation options can be implemented in different forest types in Ba Be National Park, Vietnam. From 1990 to 2000, forest in the study area faced a high rate of forest cover loss and degradation. During the next decade from 2000 to 2010, total forest cover increased gradually. However, the natural forest area still decreased. In our household survey (n=103), respondents reported that main drivers of deforestation and forest degradation in those areas were timber extraction for commercial or subsistence purposes, shifting cultivation, inadequate forest management, bribes to forest rangers, felling trees for firewood and bamboo shoots, and conversion to Mo (Manglietia conifera) and other perennial plants. There are some differences in those drivers between the three villages surveyed. From 2000 to 2010, several land use changes such as the conversion of poor timber forest into recovered timber forest, medium timber forest into poor timber forest and planted forest into bare land with scattered trees caused more than 8,000 tCO2e emissions per year. In regard to opportunity costs, most of the avoidance options have negative opportunity costs, which mean potential benefits. Within the current carbon market price, the avoidance can be applied to reduce approximately 7,900 tCO2e emissions (about 98% reduction) per year in the three communes surveyed.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.24.153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Ishiguri, H. Aiso, Mirai Hirano, R. Yahya, I. Wahyudi, J. Ohshima, K. Iizuka, S. Yokota
The growth characteristics, anatomical characteristics, and wood properties of Dysoxylum mollissimum, a fastgrowing tree species, were investigated. To clarify the effect of radial growth rate on these characteristics and properties, 10-yearold trees planted in Bengkulu, Indonesia were examined and classified into three categories (fast-, medium-, and slow-growing). Xylem maturation type was also evaluated in this species. The mean values of stem diameter, tree height, stem volume, and stresswave velocity in the 50 measured trees were 18.0 cm, 10.6 m, 0.119 m, and 3.48 km s, respectively. Mean values of anatomical characteristics and wood properties in nine selected trees were as follows: vessel diameter, 129 μm; vessel frequency, 3.5 vessels mm; cell wall thickness of wood fiber, 1.2 μm; percentages of vessels, wood fiber, ray parenchyma, axial parenchyma, and cell wall, 8.8, 72.9, 12.4, 5.9, and 33.5%, respectively; vessel element length, 0.36 mm; wood fiber length, 1.04 mm; basic density, 0.45 g cm; and compressive strength parallel to the grain in green condition, 29.9 MPa. These obtained values were similar to or smaller than previous results obtained in research on other Dysoxylum spp. For almost all of the anatomical characteristics and wood properties, no significant differences among the categories were found. This suggests that the trees with faster radial growth characteristics do not always produce lower quality wood in this species. Judging from the radial variation of anatomical characteristics, the xylem maturation of this species depends on the diameter growth, and it might occur at around 6 to 8 cm from the pith.
对速生树种mollissimum Dysoxylum的生长特征、解剖特征和木材特性进行了研究。为了阐明径向生长速率对这些特征和特性的影响，研究人员对印度尼西亚Bengkulu种植的10年树龄树木进行了研究，并将其分为三类(快速、中等和缓慢生长)。木质部成熟类型也进行了评价。50棵测量树的茎粗、树高、茎体积和应力波速度平均值分别为18.0 cm、10.6 m、0.119 m和3.48 km s。9株树木解剖特征和木材性能的平均值如下:血管直径为129 μm;容器频率，3.5容器mm;木纤维细胞壁厚度为1.2 μm;导管、木纤维、射线薄壁、轴向薄壁和细胞壁所占比例分别为8.8、72.9、12.4%、5.9和33.5%;容器元件长度，0.36 mm;木纤维长度，1.04 mm;基本密度，0.45 g cm;绿态平行晶粒抗压强度为29.9 MPa。这些结果与以往对其他木属的研究结果相似或小于。在几乎所有的解剖特征和木材性质上，不同分类间没有发现显著差异。这表明，具有更快径向生长特征的树木并不总是生产低质量的木材。从解剖特征的径向变化来看，该树种木质部的成熟取决于直径的生长，可能发生在距髓6 ~ 8 cm左右。
{"title":"Effects of radial growth rate on anatomical characteristics and wood properties of 10-year-old Dysoxylum mollissimum trees planted in Bengkulu, Indonesia","authors":"F. Ishiguri, H. Aiso, Mirai Hirano, R. Yahya, I. Wahyudi, J. Ohshima, K. Iizuka, S. Yokota","doi":"10.3759/TROPICS.25.23","DOIUrl":"https://doi.org/10.3759/TROPICS.25.23","url":null,"abstract":"The growth characteristics, anatomical characteristics, and wood properties of Dysoxylum mollissimum, a fastgrowing tree species, were investigated. To clarify the effect of radial growth rate on these characteristics and properties, 10-yearold trees planted in Bengkulu, Indonesia were examined and classified into three categories (fast-, medium-, and slow-growing). Xylem maturation type was also evaluated in this species. The mean values of stem diameter, tree height, stem volume, and stresswave velocity in the 50 measured trees were 18.0 cm, 10.6 m, 0.119 m, and 3.48 km s, respectively. Mean values of anatomical characteristics and wood properties in nine selected trees were as follows: vessel diameter, 129 μm; vessel frequency, 3.5 vessels mm; cell wall thickness of wood fiber, 1.2 μm; percentages of vessels, wood fiber, ray parenchyma, axial parenchyma, and cell wall, 8.8, 72.9, 12.4, 5.9, and 33.5%, respectively; vessel element length, 0.36 mm; wood fiber length, 1.04 mm; basic density, 0.45 g cm; and compressive strength parallel to the grain in green condition, 29.9 MPa. These obtained values were similar to or smaller than previous results obtained in research on other Dysoxylum spp. For almost all of the anatomical characteristics and wood properties, no significant differences among the categories were found. This suggests that the trees with faster radial growth characteristics do not always produce lower quality wood in this species. Judging from the radial variation of anatomical characteristics, the xylem maturation of this species depends on the diameter growth, and it might occur at around 6 to 8 cm from the pith.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.25.23","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Doan, A. Sano, H. Tamaki, H. Pham, Xo Hoa Duong, Y. Terashima
Indigenous oil-degrading bacteria (ODB) were screened from two islands, Iriomote, Japan and Con Dao, Vietnam. These islands are considered predicted contamination sites from oil spillage on a nearby busy transportation route. The aim of this study was to compare the degradation abilities of bacterial isolates from the two different study areas for crude oil, n-alkanes, and polycyclic aromatic hydrocarbons. Comparing the two study areas, the numbers of the total bacteria and ODB showed the same distribution tendencies. There were no differences between Iriomote and Con Dao in the counts of the total bacteria and ODB in sediment samples, while those in seawater samples were statistically lower for Iriomote than for Con Dao. A total of 45 isolates, 25 from Iriomote and 20 from Con Dao, belonging to 18 genera, were isolated. Among 11 genera detected on Iriomote, the dominant genera were Achromobacter, Pseudomonas, and Ochrobactrum. Among 11 genera from Con Dao, the dominant genera were Pseudomonas and Microbacterium. The degradation ability of the isolates was studied for crude oil, two kinds of n-alkanes, and two kinds of polycyclic aromatic hydrocarbons (PAHs). The numbers of the isolates that degraded more than 50 percent of the crude oil and n-alkanes and 25 percent of the PAHs present in the media were higher for Iriomote (3, 11, and 2, respectively) than for Con Dao (2, 4, and 1, respectively). It is noteworthy that the isolates of Pseudomonas putida and Ochrobactrum anthropi could degrade more than 40 percent of the oil and n-alkanes and more than 25 percent of the PAHs present in the media.
从日本伊洛默特岛和越南Con Dao两个岛屿上筛选了原生石油降解细菌(ODB)。这些岛屿被认为是附近繁忙交通路线上石油泄漏的预测污染地点。本研究的目的是比较两个不同研究区分离的细菌对原油、正构烷烃和多环芳烃的降解能力。两个研究区细菌总数和ODB的分布趋势一致。在沉积物样品中，Iriomote和Con Dao的总细菌和ODB计数没有差异，而在海水样品中，Iriomote的总细菌和ODB计数低于Con Dao。共分离菌株45株，其中Iriomote菌株25株，Con Dao菌株20株，隶属18属。在Iriomote上检出的11个属中，优势属为无色杆菌属(Achromobacter)、假单胞菌属(Pseudomonas)和无色杆菌属(Ochrobactrum)。Con Dao 11个属中以假单胞菌和微杆菌为优势属。研究了分离菌对原油、两种正构烷烃和两种多环芳烃的降解能力。Iriomote菌株(分别为3、11和2)比Con Dao菌株(分别为2、4和1)降解培养基中50%以上的原油和正烷烃以及25%以上的多环芳烃的菌株数量要高。值得注意的是，恶臭假单胞菌和人类嗜杆菌的分离株可以降解培养基中存在的40%以上的油和正构烷烃以及25%以上的多环芳烃。
{"title":"Identification and biodegradation characteristics of oil-degrading bacteria from subtropical Iriomote Island, Japan, and tropical Con Dao Island, Vietnam","authors":"C. Doan, A. Sano, H. Tamaki, H. Pham, Xo Hoa Duong, Y. Terashima","doi":"10.3759/TROPICS.MS16-01","DOIUrl":"https://doi.org/10.3759/TROPICS.MS16-01","url":null,"abstract":"Indigenous oil-degrading bacteria (ODB) were screened from two islands, Iriomote, Japan and Con Dao, Vietnam. These islands are considered predicted contamination sites from oil spillage on a nearby busy transportation route. The aim of this study was to compare the degradation abilities of bacterial isolates from the two different study areas for crude oil, n-alkanes, and polycyclic aromatic hydrocarbons. Comparing the two study areas, the numbers of the total bacteria and ODB showed the same distribution tendencies. There were no differences between Iriomote and Con Dao in the counts of the total bacteria and ODB in sediment samples, while those in seawater samples were statistically lower for Iriomote than for Con Dao. A total of 45 isolates, 25 from Iriomote and 20 from Con Dao, belonging to 18 genera, were isolated. Among 11 genera detected on Iriomote, the dominant genera were Achromobacter, Pseudomonas, and Ochrobactrum. Among 11 genera from Con Dao, the dominant genera were Pseudomonas and Microbacterium. The degradation ability of the isolates was studied for crude oil, two kinds of n-alkanes, and two kinds of polycyclic aromatic hydrocarbons (PAHs). The numbers of the isolates that degraded more than 50 percent of the crude oil and n-alkanes and 25 percent of the PAHs present in the media were higher for Iriomote (3, 11, and 2, respectively) than for Con Dao (2, 4, and 1, respectively). It is noteworthy that the isolates of Pseudomonas putida and Ochrobactrum anthropi could degrade more than 40 percent of the oil and n-alkanes and more than 25 percent of the PAHs present in the media.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.MS16-01","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70010027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forestland allocation (FLA) policy in Vietnam aimed at conserving forests and improving local livelihoods. In regard to the effectiveness of FLA, some authors reported improvements in forest cover and quality, whereas others stated inappropriate implementation process and minor impacts on household income. Hence, this study examined whether disturbances in initial stage still existed, how allocated forestlands were utilized, and how FLA contributed to local livelihoods under different forest management regimes. D village of Nam Dong district, where FLA was introduced in 1995, was selected as a case, and 78 households were randomly selected for household interviews. The results revealed that shifting cultivation, once widely reported in mountainous regions, had already ceased before our survey. Natural forests allocated to groups were mainly utilized for non-wood forest product (NWFP) collection, regardless of whether those users had an allocation. Individually allocated areas were converted to acacia and recently to rubber plantations. The rotation of acacia plantation was five to seven years with intercropping cassava in the initial stage. FLA contributed to adjusting an uneven distribution of farmland and income, but the effect remained nominal. The role of FLA in income generation was limited due to small allocation area per household (1.50 ha on average). Switching to rubber trend was another reason of limited income derived from FLA. Therefore NWFP played a more significant role in the household economy than plantation yields. Investment in livestock was first preference of respondents, which suggests the importance of small-scale livestock rearing in the areas facing land shortage.
{"title":"The effect of forestland allocation to the livelihoods of local people in the North Central Coast of Vietnam: A case in Nam Dong district","authors":"T. Nguyen, M. Masuda, S. Iwanaga","doi":"10.3759/TROPICS.24.169","DOIUrl":"https://doi.org/10.3759/TROPICS.24.169","url":null,"abstract":"Forestland allocation (FLA) policy in Vietnam aimed at conserving forests and improving local livelihoods. In regard to the effectiveness of FLA, some authors reported improvements in forest cover and quality, whereas others stated inappropriate implementation process and minor impacts on household income. Hence, this study examined whether disturbances in initial stage still existed, how allocated forestlands were utilized, and how FLA contributed to local livelihoods under different forest management regimes. D village of Nam Dong district, where FLA was introduced in 1995, was selected as a case, and 78 households were randomly selected for household interviews. The results revealed that shifting cultivation, once widely reported in mountainous regions, had already ceased before our survey. Natural forests allocated to groups were mainly utilized for non-wood forest product (NWFP) collection, regardless of whether those users had an allocation. Individually allocated areas were converted to acacia and recently to rubber plantations. The rotation of acacia plantation was five to seven years with intercropping cassava in the initial stage. FLA contributed to adjusting an uneven distribution of farmland and income, but the effect remained nominal. The role of FLA in income generation was limited due to small allocation area per household (1.50 ha on average). Switching to rubber trend was another reason of limited income derived from FLA. Therefore NWFP played a more significant role in the household economy than plantation yields. Investment in livestock was first preference of respondents, which suggests the importance of small-scale livestock rearing in the areas facing land shortage.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.24.169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Forest conservation and rehabilitation policies in Vietnam: their assessments and local responses","authors":"M. Masuda, S. Iwanaga, N. Kaida, K. Yoshino","doi":"10.3759/TROPICS.24.139","DOIUrl":"https://doi.org/10.3759/TROPICS.24.139","url":null,"abstract":"","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/TROPICS.24.139","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70002615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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