• Title/Summary/Keyword: tropical forests

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Potential use of essential oils to control the leaf-cutting ants; Atta sexdens rubropilosa and Acromyrmex subterraneus molestans (Hymenoptera: Formicidae)

  • Ribeiro, Rafael C.;Fouad, Hany A.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.32 no.1
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    • pp.26-34
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    • 2016
  • The present study was developed in order to evaluate the effect of five essential oils on the workers of the leaf-cutting ants; Atta sexdens rubropilosa and Acromyrmex subterraneus molestans by contact with a treated surface and ingestion with a treated leaves.. The essential oils of cinnamon, clove and mustard had generally more effective with 5, 10 and 15% concentrations after 24, 48, 72 and 96 h against workers of A. sexdens rubropilosa and A. subterraneus molestans in contact bioassay, but mustard was the most effective in ingestion bioassay on both species. On the other hand, there was no significant difference among the essential oils with 1% concentration and control after 24, 48 and 72 h of treatment in contact and ingestion bioassays against workers of A. sexdens rubropilosa . However, Andiroba oil had less efficiency values in all concentrations been used. Therefore, the essential oils of mustard, cinnamon and clove have contact and ingestion effects on workers of A. sexdens rubropilosa and A. subterraneus molestans, and may be promising on the leaf-cutting ant control.

Basal Area-Stump Diameter Models for Tectona grandis Linn. F. Stands in Omo Forest Reserve, Nigeria

  • Chukwu, Onyekachi;Osho, Johnson S.A.
    • Journal of Forest and Environmental Science
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    • v.34 no.2
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    • pp.119-125
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    • 2018
  • The tropical forests in developing countries are faced with the problem of illegal exploitation of trees. However, dearth of empirical means of expressing the dimensions, structure, quality and quantity of a removed tree has imped conviction of offenders. This study aimed at developing a model that can effectively estimate individual tree basal area (BA) from stump diameter (Ds) for Tectona grandis stands in Omo Forest Reserve, Nigeria, for timber valuation in case of illegal felling. Thirty-six $25m{\times}25m$ temporary sample plots (TSPs) were laid randomly in six age strata; 26, 23, 22, 16, 14, and 12 years specifically. BA, Ds and diameter at breast height were measured in all living T. grandis trees within the 36 TSPs. Least square method was used to convert the counted stumps into harvested stem cross-sectional areas. Six basal area models were fitted and evaluated. The BA-Ds relationship was best described by power model which gave least values of Root mean square error (0.0048), prediction error sum of squares (0.0325) and Akaike information criterion (-15391) with a high adjusted coefficient of determination (0.921). This study revealed that basal area estimation was realistic even when the only information available was stump diameter. The power model was validated using independent data obtained from additional plots and was found to be appropriate for estimating the basal area of Tectona grandis stands in Omo Forest Reserve, Nigeria.

Ethnomedicinal and pharmacological activities of Mochrus (Bombax ceiba Linn.): An overview

  • Rani, Seema;Rahman, Khaleequr;Sultana, Arshiya
    • CELLMED
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    • v.6 no.1
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    • pp.2.1-2.9
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    • 2016
  • Traditional system of medicine mentioned the use of plants in treatment of various human ailments. Mochrus (Bombax ceiba Linn.) is one of the medicinal plants used in Unani medicine since time immemorial. It is a very tall tree with approximately 150 feet height. It is widely found in temperate Asia, tropical Asia, Africa and Australia. In India, it can be found at altitudes up to 1500 m. In peninsular India, the tree is very common in the dry as well as moist deciduous forests and near rivers. It is reported to possess qabiz (constipative); mujaffif (siccative); muqawwi rehm (uterine tonic); nafi sailan rehm (beneficial in leucorrhea); mumsik wa mughalliz mani (increase consistency of semen); muallide mani (production of semen); habise tams (amenorrhoic); dafi fasaad khoon wa safra (purifies blood and bile); taskeen hiddat aza (hotness of organs); muqawi asnan wa lissa (tonic to teeth and gums) etc. Ethnobotanical studies prove that it is used in diarrhoea, asthma, impotency, boils, wounds, leprosy, pimples and many other skin diseases. It is an anthelmintic remedy since ancient time. Pharmacological studies like hypotensive, antioxidant, analgesic, anti-inflammatory, antipyretic, antiangiogenic, anti- bacterial, cytotoxic, hepatoprotective, diuretic, anthelmintic, anticancer, spermatogenic and anti-helicobacter pylori activities have been evaluated for various parts of this plant that confirms to its use in classical medicine.

The Carbon Sequestration Potential of Forestry Sector: Bangladesh Context

  • Sohel, Md. Shawkat Islam;Rana, Md. Parvez;Alam, Mahbubul;Akhter, Sayma;Alamgir, Mohammed
    • Journal of Forest and Environmental Science
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    • v.25 no.3
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    • pp.157-165
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    • 2009
  • Forests potentially contribute to global climate change through their influence on the global carbon (C) cycle. The Kyoto Protocol provides for the involvement of developing countries in an atmospheric greenhouse gas reduction regime under its Clean Development Mechanism (CDM). Carbon credits are gained from reforestation and afforestation activities in developing countries. Bangladesh, a densely populated tropical country in South Asia, has a huge degraded forestland, which can be reforested by CDM projects. To realize the potential of the forestry sector in developing countries like Bangladesh for full-scale emission mitigation, the carbon sequestration potential should be integrated with the carbon trading system under the CDM of the Kyoto Protocol. This paper discusses the prospects of carbon trading in Bangladesh, in relation to the CDM, in the context of global warming.

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The Vietnam War and the Reception of Ecocide Consciousness (베트남전쟁과 에코사이드 의식의 수용)

  • Kim, Ilgu
    • English & American cultural studies
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    • v.18 no.4
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    • pp.1-31
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    • 2018
  • It is needless to say that America's indiscriminate artillery and chemical attacks have worsened the conditions of Vietnam's tropical rain forests, causing war-torn combat troops and civilians to suffer more from the participation and aftermath of the Vietnam war. Around two decades after the Vietnam War, American and Vietnamese writers dealing with the destruction of the human and nature of the Vietnam War and the following traumatic experience commonly report the horrors of inhumane warfare, but some differences among them appear in the reception of the ecocide consciousness. For American writers who had been involuntarily involved or who had stayed in the back area as interpreters and counter-intelligence force, the Vietnam War was often a kind of exotic "addicted adventure" which their American hometown could not provide. But apart from overcoming postwar post-traumatic stress by writing of healing which was shared with American war writers, Vietnamese writers have been able to overcome the scars of war as the communal memorial, which Jonathan Shay emphasized as the necessary comforting ritual by community members showing the sign of honor and care. On the other hand, American war writers were on the side of "separate peace," as Jeong stressed, and the Vietnam War to them was more racist like the case of "body count." Nevertheless, it is fortunate that the hideous experience of war could turn them all into the creativity pool, just as the 5,000 square mile of bomb creators have been used as the postwar fish ponds.

A new record for the Korean flora: Nervilia nipponica Makino (Orchidaceae) (우리나라 미기록 식물: 영아리난초(난초과))

  • Kim, Chan-Soo;Moon, Myung-Ok;Koh, Jung-Goon
    • Korean Journal of Plant Taxonomy
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    • v.39 no.3
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    • pp.229-232
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    • 2009
  • Nervilia nipponica Makino (Orchidaceae), a genus and species previously unrecorded for the Korean flora, was collected in the deciduous forests of Mt. Halla, Jeju Island. This species was known to be distributed mainly from tropical to subtropical regions of Taiwan and Japan. Genus Nervilia is distinguished from other genera of tribe Nervilieae (Orchidaceae) by having only a single, plicate leaf which develops and senesces before flowering shoots appear, stems unbranched, two pollinia, and sometimes lacking a viscidium.

Mithun (Bos frontalis): the neglected cattle species and their significance to ethnic communities in the Eastern Himalaya - A review

  • Dorji, Tashi;Wangdi, Jigme;Shaoliang, Yi;Chettri, Nakul;Wangchuk, Kesang
    • Animal Bioscience
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    • v.34 no.11
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    • pp.1727-1738
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    • 2021
  • Objective: This review consolidates the available information on the socio-economic and ecological significance of Mithun in the lives of ethnic communities in the Eastern Himalaya. Methods: Standard guidelines were followed for the review and data collection was carried out at three stages; literature search, literature screening, and literature review and analysis. Results: Records indicate a long association of Mithun with the ethnic groups. Mithun serves as a symbol of pride and local currency for barter trade in the ethnic society. Its utilities range from being used as a bride price to settling legal disputes. Several cultural festivals and local ceremonies are celebrated around this bovine. Due to its semi-wild nature, this animal also has an ecological role to conserve broad leaf sub-tropical forests. However, it remains neglected and has not received policy attention, leading to a stagnated growth. The institutions for Mithun research and development are also weak. Furthermore, the species is under threat from new diseases and habitat alteration triggered by climate change. Conclusion: Founded on the current state of knowledge, there is a need for institutional development, strengthening institutional linkages, and promoting regional cooperation among Mithun rearing countries for further research and development of this unique cattle.

Physical and Mechanical Properties of Methyl Methacrylate-Impregnated Wood from Three Fast-Growing Tropical Tree Species

  • Hadi, Yusuf Sudo;Massijaya, Muh Yusram;Zaini, Lukmanul Hakim;Pari, Rohmah
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.3
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    • pp.324-335
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    • 2019
  • Timber from plantation forests has inferior physical and mechanical properties compared to timber from natural forest because it is mostly from fast-growing tree species that are cut at a young age. Filling cell voids with methyl methacrylate (MMA) can improve the wood properties. The purpose of this study was to determine the physical and mechanical properties of MMA-impregnated wood from three fast-growing wood species, namely jabon (Anthocephalus cadamba (Roxb.) Miq.), mangium (Acacia mangium Willd) and pine (Pinus merkusii Jungh. & de Vriese). Wood samples were either immersed in MMA monomer or impregnated with it and then heated to induce the polymerization process. Jabon, which was the lowest density wood, had the highest polymer loading, followed by pine and mangium. The physical and mechanical properties of samples were affected by wood species and the presence of MMA, with higher-density wood having better properties than wood with a lower density. Physical and mechanical properties of MMA wood were enhanced compared to untreated wood. Furthermore, the impregnation process was better than immersion process resulting the physical and mechanical properties. Based on MOR values, the MMA woods were one strength class higher compared to untreated wood with regard to Strength Classification of Indonesian Wood.

Habitat Suitability Modeling of Endangered Cyathea spinulosa (Wall. ex Hook.) in Central Nepal

  • Padam Bahadur Budha;Kumod Lekhak;Subin Kalu;Ichchha Thapa
    • Journal of Forest and Environmental Science
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    • v.39 no.2
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    • pp.65-72
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    • 2023
  • The endangered species of Cyathea spinulosa (tree ferns) are among the least concerned ferns of Nepal that bring threats to them and their habitat. A way to reduce such threats is by maintaining a database of species' whereabouts and generating a scientific understanding the habitat preferences. This will eventually help in the formulation of conservation plans for the species. This research aimed to characterize the suitable habitat of C. spinulosa by enumerating the location of species in the Panchase Forests of central Nepal. The statistical index method was applied to relate the occurrence locations of species with various environmental factors for the development of indices. The suitable habitat of C. spinulosa (more and most suitable categories) covered 119 km2 and accounted for 43% of the total area studied. 74.4% of occurrence locations of C. spinulosa were recorded from these habitats. The habitat characteristics suitable for C. spinulosa were: proximity to streams (high moisture), land covered by forested area (shady area), mid-elevations of hills about 1,000 m to 2,000 m (sub-tropical climate), slope gradient of 20° to 40° (steep slopes), and northern to eastern aspects. These habitat characteristics could be considered for in-situ protection of tree ferns and designating the conservation plots.

Estimation of Stand-level Above Ground Biomass in Intact Tropical Rain Forests of Brunei using Airborne LiDAR data (항공 LiDAR 자료를 이용한 브루나이 열대우림의 임분단위 지상부 생체량 추정)

  • Yoon, Mihae;Kim, Eunji;Kwak, Doo-Ahn;Lee, Woo-Kyun;Lee, Jong-Yeol;Kim, Moon-Il;Lee, Sohye;Son, Yowhan;Salim, Kamariah Abu
    • Korean Journal of Remote Sensing
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    • v.31 no.2
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    • pp.127-136
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    • 2015
  • This study aims to quantify the stand-level above ground biomass in intact tropical rain forest of Brunei using airborne LiDAR data. Twenty four sub-plots with the size of 0.09ha ($30m{\times}30m$) were located in the 25ha study area along the altitudinal gradients. Field investigated data (Diameter at Breast Height (DBH) and individual tree position data) in sub-plots were used. Digital Surface Model (DSM), Digital Terrain Model (DTM) and Canopy Height Model (CHM) were constructed using airborne LiDAR data. CHM was divided into 24 sub-plots and 12 LiDAR height metrics were built. Multiple regression equation between the variables extracted from the LiDAR data and biomass calculated by using a allometric equation was derived. Stand-level biomass estimated from LiDAR data were distributed from 155.81 Mg/ha to 597.21 Mg/ha with the mean value of 366.48 Mg/ha. R-square value of the verification analysis was 0.84.