• Title/Summary/Keyword: TROPICAL RAIN FOREST

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Exploring on the Defense Strategies against Hervivory of Several Broad-leaved Tree Species in Solomon Islands (솔로몬제도에 생육중인 몇 활엽수종의 초식에 대한 방어전략 탐색)

  • Kim, Gab-Tae
    • Korean Journal of Environment and Ecology
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    • v.24 no.5
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    • pp.611-616
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    • 2010
  • To explore on the defense strategies against hervivory of broadleaved tree species growing in tropical rain forest, Solomon Islands, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves of 26 tree species, collected from the trees growing in Guadalcanal, New Georgia, and Tetepare islands, were investigated from Feb. 25 to March 5, 2010. The results are summarized as follows. Six tree species including Terminalia catappa(23.08%) among total 26 species have domatia structure. Especially, domatia of T. catappa reveals two types; pouch type and pit+tuft type. Predatory mites are observed on the leaves of only three species including T. catappa. Predatory mites' number per leaf or leaflet proved a few, 0.33~0.40. Insect pests destroying the leaf of tree species are such as aphids, Diaspididae sp., larva of Lepidoptera, and Eriosoma sp.(Pemphlogidae). Ants are co-works with aphids and Diaspididae sp., and supports herbivores. These results indicate that protective mutualisms between tree and predatory mites may be less frequent in woody species of tropical rain forest in Solomon Islands.

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.

Modeling the Natural Occurrence of Selected Dipterocarp Genera in Sarawak, Borneo

  • Teo, Stephen;Phua, Mui-How
    • Journal of Forest and Environmental Science
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    • v.28 no.3
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    • pp.170-178
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    • 2012
  • Dipterocarps or Dipterocarpaceae is a commercially important timber producing and dominant keystone tree family in the rain forests of Borneo. Borneo's landscape is changing at an unprecedented rate in recent years which affects this important biodiversity. This paper attempts to model the natural occurrence (distribution including those areas with natural forests before being converted to other land uses as opposed to current distribution) of dipterocarp species in Sarawak which is important for forest biodiversity conservation and management. Local modeling method of Inverse Distance Weighting was compared with commonly used statistical method (Binary Logistic Regression) to build the best natural distribution models for three genera (12 species) of dipterocarps. Database of species occurrence data and pseudoabsence data were constructed and divided into two halves for model building and validation. For logistic regression modeling, climatic, topographical and edaphic parameters were used. Proxy variables were used to represent the parameters which were highly (p>0.75) correlated to avoid over-fitting. The results show that Inverse Distance Weighting produced the best and consistent prediction with an average accuracy of over 80%. This study demonstrates that local interpolation method can be used for the modeling of natural distribution of dipterocarp species. The Inverse Distance Weighted was proven a better method and the possible reasons are discussed.

Acacia mangium Willd. - A Fast Growing Tree for Tropical Plantation

  • Hegde, Maheshwar;Palanisamy, K.;Yi, Jae Seon
    • Journal of Forest and Environmental Science
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    • v.29 no.1
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    • pp.1-14
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    • 2013
  • Acacia mangium is an evergreen fast-growing tropical tree, which can grow up to 30 m tall and 50 cm thick, under favorable conditions. It is a low-elevation species associated with rain forest margins and disturbed, well-drained acid soils. It is native to Papua, Western Irian Jaya and the Maluku islands in Indonesia, Papua New Guinea and north-eastern Queensland in Australia. Due to its rapid growth and tolerance of very poor soils, A. mangium was introduced into some Asian, African and western hemisphere countries where it is used as a plantation tree. A. mangium has good quality wood traits, such as a comparatively low proportion of parenchymatous cells and vessels, white and hard wood, and high calorific value. Therefore, it is useful for a variety of purposes, such as furniture, cabinets, turnery, floors, particleboard, plywood, veneer, fence posts, firewood, and charcoal. It is also being used in pulp and paper making because it has good pulp traits, with high yields of pulp, quality of kraft, and produces paper with good optical, physical and surface properties. Because there are significant provenance differences in growth rate, stem straightness, heartwood formation and frequency of multiple leaders, the productivity and quality also varies depending upon environmental conditions, so genetic improvement programmes have been undertaken in countries like Australia, India, Indonesia, Malaysia, the Philippines, Taiwan and Thailand. The programme includes provenance identifications and testing, plus tree selection and clonal multiplication, establishment of seed orchards and hybridization. The phenology, reproductive biology, fruit characteristics, silvicultural practices for cultivation, pest and diseases problems, production of improved planting stock, harvesting, wood properties and utilization have been discussed in this paper.

Aboveground biomass of tropical rain forests by forest type in Brunei Darussalam (브루나이 열대우림의 산림 유형별 지상부 바이오매스 추정)

  • Jang, Minju;Roh, Yujin;Kim, Hyung-sub;Lee, Jeongmin;Son, Yowhan
    • Korean Journal of Environmental Biology
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    • v.39 no.3
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    • pp.266-272
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    • 2021
  • The aboveground biomass (AGB) was estimated in mixed dipterocarp forests (MDF), peat swamp forests (PSF), and heath forests (HF) in Brunei Darussalam. A total of 81 (20 m×20 m) plots were established for MDF, PSF, and HF in three regions. The diameter at breast height(DBH) of all live trees (DBH≥10 cm) was measured within the plots. The AGB was calculated using an allometric equation with the measured DBH. The AGB(Mg ha-1) for MDF, PSF, and HF was 603.3±159.9, 305.9±23.4, and 284.3±19.3, respectively, and was significantly different among the forest types (p<0.05). The greater AGB in MDF than those in PSF and HF was due to the presence of emergent trees in MDF. The results showed that the number of emergent trees varied by forest type. Consequently, the appearance of the emergent trees could be one of the main factors affecting AGB in Southeast Asia's tropical rain forests.

Satellite Rainfall Monitoring: Recent Progress and Its Potential Applicability (인공위성 강우모니터링: 최근 동향 및 활용 방안)

  • Kim Seong-Joon;Shin Sa-Chul;Suh Ae-Sook
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.1 no.2
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    • pp.142-150
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    • 1999
  • During the past three decades after the first attempt to use satellite imagery or derived cloud products for rainfall estimation, much is known and understood concerning the scope and difficulties of satellite rainfall monitoring. After a brief general introduction this paper reviews recent progress in this field with special reference to improvement of algorithms, inter-comparison projects, integrative use of data from different sources, increasing lengths of data records and derived products, and interpretability of rainfall results. Also the paradigm of TRMM (Tropical Rainfall Measuring Mission) which is the first space mission(1997) dedicated to measuring tropical and subtropical rainfall though microwave and visible/infrared sensors, including the first spaceborne rain radar was introduced, and the potential applicability to the field of agriculture and water resources by combining satellite imagery is described.

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Native Hawaiian Collection Systems in Lava Tubes(Caves) and Fault Cracks: Puna - Ka'u Districts, Hawaii

  • Martin, James F.
    • Journal of the speleological society of Korea
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    • no.4
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    • pp.41-50
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    • 1996
  • The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

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An Analysis of the Rice Situation in Nicaragua for Improving National Production.

  • Chang-Min Lee;Oporta Juan;Ho-Ki Park;Hyun-Su Park;Jeonghwan Seo;Man-Kee Baek;Jae-Ryoung Park;O-Young Jeong
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.90-90
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    • 2022
  • Nicaragua is located in Central America, climatic conditions are considered tropical dry forest. Statistics reflex that in Nicaragua exits 24,000 rice farmers. National rice production only covers 73% of the national consumption. It exists two sowing system: irrigation and rainfed. Varieties used in both systems are mid-late maturity (120-135 days), there are 14 released varieties for irrigation, eight for rainfed, and eight landraces used in rainfed. The current breeding system (introduction of lines from Colombia) has increased the national production, however, has some limitation due to the lack of enough variability, reducing the proability of finding good genotypes and therefore the possibility of satisfying 100% of the demand. The purpose of this study was to analyze the problems that must be resolved in the short and long term to improve rice productivity in Nicaragua. In this paper we explain some proposal for an improvement plan. The selection of varieties with high adaptability to various cultivation environmental conditions it is necessary, also to thoroughly manage seed purity to supply certified seeds. In rice cultivation technology, it needs to improve seedling standing and weeding effect by improving soil leveling and water-saving cultivation technology. Also, proper fertilization and planting density must be established in irrigated and rain-fed areas. Furthermore, capacity must be strengthened by collecting and training with the most recent agricultural technology information, as well as by revitalizing the union rather than the individual farmer. It is necessary to develop varieties highly adaptable to the Nicaraguan cultivation environment, as well as to expand irrigation facilities and cultivation technology suitable for weather conditions in rain-fed areas. Last, it is necessary to maintain the consistency of agricultural policy for continuous and stable rice production in response to climate change events such as drought or intermittent heavy rain.

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Research for the Selection of Agricultural environment in Papua New Guinea (파푸아뉴기니 농업 환경 기초조사)

  • Chang, Kwang Jin;Koo, Hyun Jung;Choi, Jang-Nam
    • Journal of Practical Agriculture & Fisheries Research
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    • v.17 no.1
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    • pp.183-204
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    • 2015
  • Papua New Guinea, birthplace of the South Pacific, is a natural nation which have potential of increasing crops output because it has optimum condition for crop growth as tropical rain forest climate under hot and humid climate. Farming village of Papua New Guinea want to produce crops for create income beyond the self-sufficiency. It needs the technological transfer such as irrigation facilities and understanding of agricultural weather condition for good crops production. In particular, it needs a improvement through pH, EC, ORP for make optimum soil condition and it need the standardization production and farm products what the consumer wants. Internationally technical cooperation is needed for agricultural development of Papua New Guinea and maintenance of international cooperation will help for economic development between the two countries. In particular, basic environment research for agricultural development of Papua New Guinea is expected to play a larger role of technical cooperation of agriculture.