We evaluate the efficacy of artificial shade shelters in promoting seedling growth and ecophysiological traits in degraded tropical forest land. Seedlings of Dyera costulata were planted in an open control plot and two open-top shade shelters (2 and 3 m in height). Leaf traits, including nitrogen content, the ratio of variable to maximum fluorescence (Fv/Fm), and chlorophyll content (SPAD value) were assessed in the nursery prior to planting, and again at 2, 7, 12, and 16 months after planting. Seedling height, diameter, biomass, and leaf number were also assessed. Shade shelters reduced light intensity to approximately 70 % and maximum temperature by up to 3.1 °C. Minimum daily air humidity was up to 12 % higher in the shelters relative to the open control. Seedling growth was better under both shelters relative to the open control, but particularly for the 2 m shelter. Seedlings planted in the open lost roughly half their leaves immediately after planting due to environmental stress, whereas leaves were retained by seedlings under the shelters. A decrease in the Fv/Fm ratio was observed in the open control both 2 and 7 months after planting, indicating photoinhibition. The maximum photosynthetic rate decreased in all conditions immediately after planting, but seedlings under the shelters recovered faster, especially in the 2 m shelter. Decreases in leaf number and photosynthetic capability in the initial stages following planting may limit seedling growth in open conditions. The improved growth and ecophysiological parameters under the shelters persisted for up to 16 months after planting, indicating that shelters may be valuable tools for reforestation and rehabilitation in degraded tropical forests.
{"title":"Artificial shade shelters mitigate harsh microclimate conditions and enhance growth in tropical tree seedlings planted in degraded land","authors":"T. Kenzo, R. Yoneda, M. Azani","doi":"10.3759/TROPICS.MS20-07","DOIUrl":"https://doi.org/10.3759/TROPICS.MS20-07","url":null,"abstract":"We evaluate the efficacy of artificial shade shelters in promoting seedling growth and ecophysiological traits in degraded tropical forest land. Seedlings of Dyera costulata were planted in an open control plot and two open-top shade shelters (2 and 3 m in height). Leaf traits, including nitrogen content, the ratio of variable to maximum fluorescence (Fv/Fm), and chlorophyll content (SPAD value) were assessed in the nursery prior to planting, and again at 2, 7, 12, and 16 months after planting. Seedling height, diameter, biomass, and leaf number were also assessed. Shade shelters reduced light intensity to approximately 70 % and maximum temperature by up to 3.1 °C. Minimum daily air humidity was up to 12 % higher in the shelters relative to the open control. Seedling growth was better under both shelters relative to the open control, but particularly for the 2 m shelter. Seedlings planted in the open lost roughly half their leaves immediately after planting due to environmental stress, whereas leaves were retained by seedlings under the shelters. A decrease in the Fv/Fm ratio was observed in the open control both 2 and 7 months after planting, indicating photoinhibition. The maximum photosynthetic rate decreased in all conditions immediately after planting, but seedlings under the shelters recovered faster, especially in the 2 m shelter. Decreases in leaf number and photosynthetic capability in the initial stages following planting may limit seedling growth in open conditions. The improved growth and ecophysiological parameters under the shelters persisted for up to 16 months after planting, indicating that shelters may be valuable tools for reforestation and rehabilitation in degraded tropical forests.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70010417","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. Okuda, Ken Shima, Toshihiro Yamada, T. Hosaka, K. Niiyama, Y. Kosugi, T. Yoneda, M. Hashim, E. S. Quah, L. Saw
{"title":"Spatiotemporal changes in biomass after selective logging in a lowland tropical rainforest in Peninsular Malaysia","authors":"T. Okuda, Ken Shima, Toshihiro Yamada, T. Hosaka, K. Niiyama, Y. Kosugi, T. Yoneda, M. Hashim, E. S. Quah, L. Saw","doi":"10.3759/tropics.ms20-03","DOIUrl":"https://doi.org/10.3759/tropics.ms20-03","url":null,"abstract":"","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70010376","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":"Faire du livre un spectacle : Le Chasteau de labour de Pierre Gringore ou l'actualisation du récit allégorique à la fin du Moyen Âge","authors":"Florian Dimeck","doi":"10.26171/TROPICS_0905","DOIUrl":"https://doi.org/10.26171/TROPICS_0905","url":null,"abstract":"","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46360317","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}
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Le gisant gothique : une image à comprendre, XVIe-XXe siècles Julien Louis
{"title":"Le gisant gothique : une image à comprendre, XVIe-XXe siècles","authors":"J. Louis","doi":"10.26171/TROPICS_0906","DOIUrl":"https://doi.org/10.26171/TROPICS_0906","url":null,"abstract":"HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Le gisant gothique : une image à comprendre, XVIe-XXe siècles Julien Louis","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45840774","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}
In this paper, I summarize the plant foods used by four sympatric Paradoxurinae civet species, based on data collected between May 2010 and June 2018, and consider their possible coexistence mechanisms on Borneo. I recorded the plants eaten by them, both by direct observation and fecal analysis, at four sites in Sabah, Malaysian Borneo. In total, I recorded 27, 27, 18, and 4 plant food items for common palm civets Paradoxurus hermaphroditus, binturongs Arctictis binturong, small-toothed palm civets Arctogalidia trivirgata, and masked palm civets Paguma larvata, respectively during the study period. The food plant species used by these species studied showed a large degree of overlap, especially among common palm civets, binturongs, and small-toothed palm civets. Based on the results of this study, differences among them in their degree of use of pioneer plant fruits and Ficus, and the acceptance of immature and unripe fruits, could enable these civets to coexist, even in a small area. However, there is no clear evidence for how they are able to coexist. This eight-year record is not enough to fully determine dietary similarities and dissimilarities or the coexistence mechanism of the four sympatric Paradoxurinae species on Borneo. More field observations with mechanical and chemical techniques are needed, not only to elucidate this mechanism but also to consider conservation of these animals and their habitats in a changing environment on Borneo.
{"title":"List of food plants of four sympatric Paradoxuriane civet species based on eight-year records on Borneo","authors":"Miyabi Nakabayashi","doi":"10.3759/tropics.ms19-13","DOIUrl":"https://doi.org/10.3759/tropics.ms19-13","url":null,"abstract":"In this paper, I summarize the plant foods used by four sympatric Paradoxurinae civet species, based on data collected between May 2010 and June 2018, and consider their possible coexistence mechanisms on Borneo. I recorded the plants eaten by them, both by direct observation and fecal analysis, at four sites in Sabah, Malaysian Borneo. In total, I recorded 27, 27, 18, and 4 plant food items for common palm civets Paradoxurus hermaphroditus, binturongs Arctictis binturong, small-toothed palm civets Arctogalidia trivirgata, and masked palm civets Paguma larvata, respectively during the study period. The food plant species used by these species studied showed a large degree of overlap, especially among common palm civets, binturongs, and small-toothed palm civets. Based on the results of this study, differences among them in their degree of use of pioneer plant fruits and Ficus, and the acceptance of immature and unripe fruits, could enable these civets to coexist, even in a small area. However, there is no clear evidence for how they are able to coexist. This eight-year record is not enough to fully determine dietary similarities and dissimilarities or the coexistence mechanism of the four sympatric Paradoxurinae species on Borneo. More field observations with mechanical and chemical techniques are needed, not only to elucidate this mechanism but also to consider conservation of these animals and their habitats in a changing environment on Borneo.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/tropics.ms19-13","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45610419","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}
Saroj Kandel, K. Harada, Sudha Adhikari, N. Dahal, M. Dhakal
There is always a conflict of interest between conservation efforts and communities living near conservation areas. Buffer zones and opportunities for ecotourism are sometimes created to lessen the negative impact of the stringent rules involved in conservation which directly impacts the livelihoods of neighbouring communities. This paper examines a Nepalese community’s perceptions of the Buffer Zone Community Forest (BZCF) rules, and investigates the interplay of rules, ecotourism, and human-wildlife conflict (HWC). Data were obtained from face-to-face household surveys and key informant interviews carried out in two Buffer Zone Villages in Chitwan National Park, Nepal. It was found that access to forest resources has become more restricted since ecotourism was introduced in the BZCF. Furthermore, contrary to expectations, settlements both closer to and farther from the forest are largely affected to the same extent by these restrictions. This study recommends better livelihood opportunities for disadvantaged groups in and around the BZCF, along with the development of forest policies based in reality to improve compliance with forest rules and to gain local support for conservation efforts.
{"title":"Local perceptions of forest rules and interactions between rules, ecotourism, and human-wildlife conflicts: Evidence from Chitwan National Park, Nepal","authors":"Saroj Kandel, K. Harada, Sudha Adhikari, N. Dahal, M. Dhakal","doi":"10.3759/tropics.ms19-07","DOIUrl":"https://doi.org/10.3759/tropics.ms19-07","url":null,"abstract":"There is always a conflict of interest between conservation efforts and communities living near conservation areas. Buffer zones and opportunities for ecotourism are sometimes created to lessen the negative impact of the stringent rules involved in conservation which directly impacts the livelihoods of neighbouring communities. This paper examines a Nepalese community’s perceptions of the Buffer Zone Community Forest (BZCF) rules, and investigates the interplay of rules, ecotourism, and human-wildlife conflict (HWC). Data were obtained from face-to-face household surveys and key informant interviews carried out in two Buffer Zone Villages in Chitwan National Park, Nepal. It was found that access to forest resources has become more restricted since ecotourism was introduced in the BZCF. Furthermore, contrary to expectations, settlements both closer to and farther from the forest are largely affected to the same extent by these restrictions. This study recommends better livelihood opportunities for disadvantaged groups in and around the BZCF, along with the development of forest policies based in reality to improve compliance with forest rules and to gain local support for conservation efforts.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/tropics.ms19-07","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41365330","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}
Tropical forest trees take up silicon (Si) and return it to the forest floor via leaf litterfall. Our objective was to explore to what extent litter Si flux and Si availability from the soil are spatially coupled. We examined these relationships within a 4-ha area of lowland mixed dipterocarp forest of Lambir Hills National Park in Borneo. Using leaf litter samples collected with litter traps, we found that Si concentration and flux of leaf litter ranged 2 - 23 mg Si g − 1 and 0.8 - 13.1 g Si m − 2 yr − 1 , respectively, whereas water-extractable Si from 0 - 10 cm deep soil ranged from 5.9 to 24.5 mg kg − 1 (0.7 to 3.0 g Si m − 2 ) at 80 litter trap locations. There was no significant correlation among these three aspects of Si cycling via trees. Water-extractable soil Si from three 95 cm deep cores showed no significant change with depth, whereas in-situ measurements with six tension lysimeters showed higher soil-water Si concentration in the upper soil layer (0 - 5 cm depth). These results suggest that spatial variations of Si concentration and flux in leaf litter do not reflect those of soil Si availability, but are modulated by distribution of tree species that differ in Si uptake. Si returned to the soil via leaf litter did not show strong spatial signals probably because solubility of Si from dead leaves differs among species. At the stand level, our results are consistent with the perspective that litter Si input enriches plant-available Si pool in the upper soil horizons in tropical forests.
热带森林树木吸收硅，并通过落叶将其送回森林。我们的目标是探索垃圾硅流量和土壤硅有效性在多大程度上是空间耦合的。我们在婆罗洲兰比尔山国家公园的一片4公顷低地混合龙脑鱼龙树林中研究了这些关系。使用垃圾收集器收集的落叶样品，我们发现，在80个垃圾收集器位置，落叶层的Si浓度和流量分别为2-23 mg Si g−1和0.8-13.1 g Si m−2 yr−1，而0-10 cm深土壤中的水可提取Si范围为5.9-24.5 mg kg−1（0.7-3.0 g Si m–2）。硅通过树木循环的这三个方面之间没有显著的相关性。来自三个95 cm深岩芯的水可提取土壤硅没有显示出随深度的显著变化，而使用六个张力溶解仪进行的原位测量显示，上部土层（0-5 cm深）的土壤水硅浓度较高。这些结果表明，落叶层中硅浓度和流量的空间变化不会影响土壤硅有效性，而是受到不同硅吸收树种分布的调节。通过落叶返回土壤的硅并没有表现出强烈的空间信号，这可能是因为硅从枯叶中的溶解度因物种而异。在林分水平上，我们的结果与落叶硅输入丰富热带森林上层土壤中植物有效硅库的观点一致。
{"title":"Spatial variations of litterfall silicon flux and plant-available silicon in highly weathered soil in a lowland mixed dipterocarp forest of Lambir Hills National Park in Borneo","authors":"R. Nakamura, M. Nakagawa, K. Kitajima","doi":"10.3759/tropics.ms19-09","DOIUrl":"https://doi.org/10.3759/tropics.ms19-09","url":null,"abstract":"Tropical forest trees take up silicon (Si) and return it to the forest floor via leaf litterfall. Our objective was to explore to what extent litter Si flux and Si availability from the soil are spatially coupled. We examined these relationships within a 4-ha area of lowland mixed dipterocarp forest of Lambir Hills National Park in Borneo. Using leaf litter samples collected with litter traps, we found that Si concentration and flux of leaf litter ranged 2 - 23 mg Si g − 1 and 0.8 - 13.1 g Si m − 2 yr − 1 , respectively, whereas water-extractable Si from 0 - 10 cm deep soil ranged from 5.9 to 24.5 mg kg − 1 (0.7 to 3.0 g Si m − 2 ) at 80 litter trap locations. There was no significant correlation among these three aspects of Si cycling via trees. Water-extractable soil Si from three 95 cm deep cores showed no significant change with depth, whereas in-situ measurements with six tension lysimeters showed higher soil-water Si concentration in the upper soil layer (0 - 5 cm depth). These results suggest that spatial variations of Si concentration and flux in leaf litter do not reflect those of soil Si availability, but are modulated by distribution of tree species that differ in Si uptake. Si returned to the soil via leaf litter did not show strong spatial signals probably because solubility of Si from dead leaves differs among species. At the stand level, our results are consistent with the perspective that litter Si input enriches plant-available Si pool in the upper soil horizons in tropical forests.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48654538","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}
Y. Nakanishi, Tatsuma Matsutani, K. Hinokidani, T. Nagai, Mami Irie
Iron solubilization in mangrove soils associated with polyphenols leached out from leaf-litter can improve iron bioavailability. In this context, the leaf-removing process by mangrove crabs would increase reacting frequency of the polyphenols in mangrove leaves with iron in the soils. In this study, we investigated ecological roles of a leaf-removing crab, Neosarmatium smithi , on the iron solubilization process. After the fallen leaves carried by the crabs to their burrows and eaten by them, polyphenols may be remained in their feces. If so, contact of polyphenols in the feces with mangrove soils could promote elution of dissolved iron from the soils. In order to demonstrate this hypothesis, we firstly surveyed the appearance ratio of the black part in crab burrows and measured total phenolic content in feces of N. smithi as well as in the black part soil. Then, we examined influences of the crab feces on dissolved iron elution from mangrove soils. As the results, the appearance ratio of the black part in the burrow was 67 % and the phenolic content in the feces, the black part, and the yellow part in crab burrows were 9.93, 0.49, and 0.12 mg g − 1 , respectively. Dissolved iron content in the solution (soil ＋ water extract from feces) was 0.65 μ g g − 1 and this content was 4.5 times higher than the control (soil ＋ distilled water). We suggest that the polyphenols remained in the feces affect to solubilize insoluble forms of iron by iron reduction and chelating properties.
铁在红树林土壤中的增溶作用与枯叶凋落物中浸出的多酚有关，可以提高铁的生物利用度。在这种情况下，红树林蟹的脱叶过程会增加红树林叶片中多酚与土壤中铁的反应频率。在本研究中，我们研究了脱叶蟹(Neosarmatium smithi)在铁溶解过程中的生态作用。当落叶被螃蟹带到它们的洞穴并被它们吃掉后，多酚可能会留在它们的粪便中。如果是这样，粪便中的多酚类物质与红树林土壤的接触可以促进土壤中溶解铁的析出。为了证明这一假设，我们首先调查了蟹洞中黑色部分的出现比例，并测量了史密斯黑斑蟹粪便和黑色部分土壤中的总酚含量。在此基础上，研究了蟹粪对红树林土壤中溶解铁的影响。结果表明，洞中黑色部分的出现率为67%，洞中粪便、黑色部分和黄色部分的酚含量分别为9.93、0.49和0.12 mg g−1。土壤+粪便水提物溶液中溶解铁的含量为0.65 μ g g−1，是土壤+蒸馏水溶液的4.5倍。我们认为，粪便中残留的多酚通过铁还原和螯合特性影响了不溶性铁的溶解。
{"title":"A role of a herbivorous crab, Neosarmatium smithi, in dissolved iron elution from mangrove ecosystems","authors":"Y. Nakanishi, Tatsuma Matsutani, K. Hinokidani, T. Nagai, Mami Irie","doi":"10.3759/tropics.ms19-06","DOIUrl":"https://doi.org/10.3759/tropics.ms19-06","url":null,"abstract":"Iron solubilization in mangrove soils associated with polyphenols leached out from leaf-litter can improve iron bioavailability. In this context, the leaf-removing process by mangrove crabs would increase reacting frequency of the polyphenols in mangrove leaves with iron in the soils. In this study, we investigated ecological roles of a leaf-removing crab, Neosarmatium smithi , on the iron solubilization process. After the fallen leaves carried by the crabs to their burrows and eaten by them, polyphenols may be remained in their feces. If so, contact of polyphenols in the feces with mangrove soils could promote elution of dissolved iron from the soils. In order to demonstrate this hypothesis, we firstly surveyed the appearance ratio of the black part in crab burrows and measured total phenolic content in feces of N. smithi as well as in the black part soil. Then, we examined influences of the crab feces on dissolved iron elution from mangrove soils. As the results, the appearance ratio of the black part in the burrow was 67 % and the phenolic content in the feces, the black part, and the yellow part in crab burrows were 9.93, 0.49, and 0.12 mg g − 1 , respectively. Dissolved iron content in the solution (soil ＋ water extract from feces) was 0.65 μ g g − 1 and this content was 4.5 times higher than the control (soil ＋ distilled water). We suggest that the polyphenols remained in the feces affect to solubilize insoluble forms of iron by iron reduction and chelating properties.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3759/tropics.ms19-06","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47569290","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}
Haruna Aiso-Sanada, I. Nezu, F. Ishiguri, Aina Nadia Najwa Mohamad Jaffar, Douglas Bungan Anak Ambun, M. Perumal, Mohd Effendi bin Wasli, T. Ohkubo, H. Abe
The aim of this study is to obtain the basic wood properties of planted Borneo ironwood (Eusideroxylon zwageri) from a plantation established about 80 years ago. Stem diameter at 1.3 m above the ground, tree height, and stress-wave velocity (SWV) of stem were measured on 36 planted E. zwageri trees. Later, core samples were collected from four trees whose measurements represented the average stem diameter of all the measured trees. Using the core samples, the moisture content (MC), basic density (BD), and compressive strength parallel to grain (CS) were measured. Dynamic Young’s modulus for longitudinal direction at green condition (E) was also calculated from SWV. There was no significant relationship between growth characteristics and SWV. Mean values of MC, BD, CS, and E were 37.2 %, 0.86 g/cm, 64.3 MPa, and 18.47 GPa, respectively. Significant differences among individual trees were found in MC, BD, and CS. In addition, radial variations were almost constant from bark side to pith side. The results indicate that longitudinal E is independent from growth characteristics, and that the E. zwageri wood tested in this study has uniform BD and CS in the radial direction.
{"title":"Basic wood properties of Borneo ironwood (Eusideroxylon zwageri) planted in Sarawak, Malaysia","authors":"Haruna Aiso-Sanada, I. Nezu, F. Ishiguri, Aina Nadia Najwa Mohamad Jaffar, Douglas Bungan Anak Ambun, M. Perumal, Mohd Effendi bin Wasli, T. Ohkubo, H. Abe","doi":"10.3759/tropics.ms19-10","DOIUrl":"https://doi.org/10.3759/tropics.ms19-10","url":null,"abstract":"The aim of this study is to obtain the basic wood properties of planted Borneo ironwood (Eusideroxylon zwageri) from a plantation established about 80 years ago. Stem diameter at 1.3 m above the ground, tree height, and stress-wave velocity (SWV) of stem were measured on 36 planted E. zwageri trees. Later, core samples were collected from four trees whose measurements represented the average stem diameter of all the measured trees. Using the core samples, the moisture content (MC), basic density (BD), and compressive strength parallel to grain (CS) were measured. Dynamic Young’s modulus for longitudinal direction at green condition (E) was also calculated from SWV. There was no significant relationship between growth characteristics and SWV. Mean values of MC, BD, CS, and E were 37.2 %, 0.86 g/cm, 64.3 MPa, and 18.47 GPa, respectively. Significant differences among individual trees were found in MC, BD, and CS. In addition, radial variations were almost constant from bark side to pith side. The results indicate that longitudinal E is independent from growth characteristics, and that the E. zwageri wood tested in this study has uniform BD and CS in the radial direction.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49126005","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 is focused on farmers’ maintenance of slash-and-burn cultivation in northwestern Zambia’s miombo woodlands and elucidates their ecological knowledge and process of clearing slash-and-burn fields. It also examines farmers’ coexistence in a multi-ethnic community in the context of the locations and ecological classification of fields cultivated by firstcomers and immigrants. The study area was S Ward in northwestern Zambia. It is written as S ward not to be specified the location. Northwestern Zambia is home to five ethnic groups: the Kaonde, who are considered the region’s firstcomers, and the Lunda, Luvale, Chokwe, and Luchazi, who are relative newcomers to S Ward. The number of villages in S Ward increased from 11 Kaonde villages in 1960 to 23 villages in 2000, of which nine were built by non-Kaonde immigrants. The population of S Ward increased with the influx of immigrants. Accordingly, the total area of cultivated land in S Ward in 2014 was 12-times higher than in 1968. Farmers in these five ethnic groups categorized the surrounding ecological environment according to landforms, soils, and vegetation, and classified the ecology as marsh or woodland. Woodland was identified as one of two types based on the accumulated soil: the outer edge of the marsh has gray soil, whereas the upland region is characterized by red soil. According to the farmers, the gray soil was soft and rich in nutrients, whereas red soil contained little sand and hardened when dried. Farmers in S Ward recognized that the gray soil in the woodland was more suitable for cultivation. The Kaonde’s cultivated fields were located at the outer edge of the marsh, as the Kaonde have lived in the area for several generations, so newcomers were forced to clear the uplands, which had remained unoccupied by the Kaonde farmers. The Kaonde and immigrants coexist in S Ward by cultivating different ecological areas and practicing different slash-and-burn cultivation systems.
{"title":"Coexistence of multiple ethnic groups practicing different slash-and-burn cultivation systems adapted to field conditions in miombo woodlands in northwestern Zambia","authors":"Masaya Hara","doi":"10.3759/tropics.ms19-01","DOIUrl":"https://doi.org/10.3759/tropics.ms19-01","url":null,"abstract":"This study is focused on farmers’ maintenance of slash-and-burn cultivation in northwestern Zambia’s miombo woodlands and elucidates their ecological knowledge and process of clearing slash-and-burn fields. It also examines farmers’ coexistence in a multi-ethnic community in the context of the locations and ecological classification of fields cultivated by firstcomers and immigrants. The study area was S Ward in northwestern Zambia. It is written as S ward not to be specified the location. Northwestern Zambia is home to five ethnic groups: the Kaonde, who are considered the region’s firstcomers, and the Lunda, Luvale, Chokwe, and Luchazi, who are relative newcomers to S Ward. The number of villages in S Ward increased from 11 Kaonde villages in 1960 to 23 villages in 2000, of which nine were built by non-Kaonde immigrants. The population of S Ward increased with the influx of immigrants. Accordingly, the total area of cultivated land in S Ward in 2014 was 12-times higher than in 1968. Farmers in these five ethnic groups categorized the surrounding ecological environment according to landforms, soils, and vegetation, and classified the ecology as marsh or woodland. Woodland was identified as one of two types based on the accumulated soil: the outer edge of the marsh has gray soil, whereas the upland region is characterized by red soil. According to the farmers, the gray soil was soft and rich in nutrients, whereas red soil contained little sand and hardened when dried. Farmers in S Ward recognized that the gray soil in the woodland was more suitable for cultivation. The Kaonde’s cultivated fields were located at the outer edge of the marsh, as the Kaonde have lived in the area for several generations, so newcomers were forced to clear the uplands, which had remained unoccupied by the Kaonde farmers. The Kaonde and immigrants coexist in S Ward by cultivating different ecological areas and practicing different slash-and-burn cultivation systems.","PeriodicalId":51890,"journal":{"name":"Tropics","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41916263","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：