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Letteratura scientifica selezionata sul tema "Rain forests – Papua New Guinea"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 19 febbraio 2022

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Articoli di riviste sul tema "Rain forests – Papua New Guinea"

Tvardikova, Katerina, e Vojtech Novotny. "Predation on exposed and leaf-rolling artificial caterpillars in tropical forests of Papua New Guinea". Journal of Tropical Ecology 28, n. 4 (1 giugno 2012): 331–41. http://dx.doi.org/10.1017/s0266467412000235.

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Abstract:Although predation is generally seen as one of the key factors determining the abundance and composition of insect herbivore communities in tropical rain forests, quantitative estimates of predation pressure in rain-forest habitats remain rare. We compared incidence of attacks of different natural enemies on semi-concealed and exposed caterpillars (Lepidoptera) in lowland and montane tropical rain forests, using plasticine models of caterpillars. We recorded attacks on caterpillars in four habitats: primary forest, secondary forest and forest fragment in lowlands (200 m asl), and montane primary forest (1700 m asl). We used 300 exposed and 300 semi-concealed caterpillars daily, and conducted the experiment for 6 d in every habitat. Daily incidence of attacks was higher on exposed caterpillars (4.95%) than on semi-concealed (leaf-rolling) caterpillars (2.99%). Attack pressure of natural enemies differed also among habitats. In the lowlands, continuous primary and secondary forests had similar daily incidence of attacks (2.39% and 2.36%) which was however lower than that found in a primary forest fragment (4.62%). This difference was caused by higher incidence of attacks by birds, ants and wasps in the forest fragment. The most important predators were birds in montane rain forests (61.9% of identified attacks), but insect predators, mostly ants, in the lowlands (58.3% of identified attacks). These results suggest that rapid decrease in the abundance of ants with altitude may be compensated by increased importance of birds as predators in montane forests. Further, it suggests that small rain-forest fragments may suffer from disproportionately high pressure from natural enemies, with potentially serious consequences for survival of their herbivorous communities.

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Rogers, Howard M. "Litterfall, decomposition and nutrient release in a lowland tropical rain forest, Morobe Province, Papua New Guinea". Journal of Tropical Ecology 18, n. 3 (26 marzo 2002): 449–56. http://dx.doi.org/10.1017/s0266467402002304.

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The analysis of litter quantity, litter decomposition and its pattern of nutrient release is important for understanding nutrient cycling in forest ecosystems. Plant growth and maintenance are partly met through nutrient cycling (O'Connell & Sankaran 1997) which is dominated by litter production and decomposition. Litter fall is a major process for transferring nutrients from above-ground vegetation to soils (Vitousek & Sanford 1986), while decomposition of litter releases nutrients (Maclean & Wein 1978). The rate at which nutrients are recycled influences the net primary productivity of a forest. Knowledge of these processes from tropical rain forests is relatively poor (O'Connell & Sankaran 1997), and in particular there are no known published studies on nutrient cycling from lowland tropical forests in Papua New Guinea. The few studies from Papua New Guinea are confined to the mid-montane forest zone (Edwards 1977, Edwards & Grubb 1982, Enright 1979, Lawong et al. 1993).

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Read, Jennifer, Geoffrey Hope e Robert Hill. "The Dynamics of Some Nothofagus-Dominated Rain Forests in Papua New Guinea". Journal of Biogeography 17, n. 2 (marzo 1990): 185. http://dx.doi.org/10.2307/2845326.

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Dahl, Chris, Stephen J. Richards e Vojtech Novotny. "The Sepik River (Papua New Guinea) is not a dispersal barrier for lowland rain-forest frogs". Journal of Tropical Ecology 29, n. 6 (11 settembre 2013): 477–83. http://dx.doi.org/10.1017/s0266467413000527.

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Abstract:Major tropical rivers have been suggested to be important dispersal barriers that increase the beta diversity of animal communities in lowland rain forests. We tested this hypothesis using assemblages of frogs in the floodplains of the Sepik River, a major river system in Papua New Guinea. We surveyed frogs at five sites within a continuous 150 × 500-km area of lowland rain forest bisected by the Sepik, using standardized visual and auditory survey techniques. We documented 769 frogs from 44 species. The similarity in species composition decreased with logarithm of geographical distance between the sites, which ranged from 82 to 465 km. The similarity decay did not depend on whether or not the compared sites were separated by the Sepik River or whether the species were aquatic or terrestrial breeders. Likewise, a DCA ordination of frog assemblages did not show separation of sites by the river as a significant factor explaining their composition. Our results suggest that even major rivers, such as the Sepik, may not act as dispersal barriers. Rivers may not limit the distribution of frogs and therefore have a limited effect on determining frog species abundance and assemblage structure in rain forests.

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Standen, Valerie. "Oligochaetes in fire climax grassland and conifer plantations in Papua New Guinea". Journal of Tropical Ecology 4, n. 1 (febbraio 1988): 39–48. http://dx.doi.org/10.1017/s0266467400002480.

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ABSTRACTEarthworm populations in grassland and plantations in the area of Bulolo, Papua New Guinea were compared with populations in nearby undisturbed rain forest. The grasslands had been maintained by burning for many years. The Pinus plantation had been developed on a burned grassland site and the Araucaria plantation on a site which had been cleared of secondary forest.The grasslands and the Pinus plantation supported moderate populations of exotic earthworms including Pontoscolex corethrurus, but no indigenous species. The Araucaria site supported a native species, Amynthas zebrus only, which was also found together with two other native species at very low density in rain forest.Exotic earthworm species widespread throughout the tropics, were present in disturbed soils and formed moderately high density populations in burned grasslands. There was no evidence that they displaced native Megascolecidae in rain forest.

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Saulei, S. M., e M. D. Swaine. "Rain Forest Seed Dynamics During Succession at Gogol, Papua New Guinea". Journal of Ecology 76, n. 4 (dicembre 1988): 1133. http://dx.doi.org/10.2307/2260639.

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Lepš, Jan, Vojtěch Novotný, Lukáš Čížek, Kenneth Molem, Brus Isua, Boen William, Richard Kutil et al. "Successful invasion of the neotropical species Piper aduncum in rain forests in Papua New Guinea". Applied Vegetation Science 5, n. 2 (24 febbraio 2002): 255–62. http://dx.doi.org/10.1111/j.1654-109x.2002.tb00555.x.

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Arihafa, Arison, e Andrew L. Mack. "Treefall Gap Dynamics in a Tropical Rain Forest in Papua New Guinea". Pacific Science 67, n. 1 (gennaio 2013): 47–58. http://dx.doi.org/10.2984/67.1.4.

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Doaemo, Willie, Midhun Mohan, Esmaeel Adrah, Shruthi Srinivasan e Ana Paula Dalla Corte. "Exploring Forest Change Spatial Patterns in Papua New Guinea: A Pilot Study in the Bumbu River Basin". Land 9, n. 9 (20 agosto 2020): 282. http://dx.doi.org/10.3390/land9090282.

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Papua New Guinea is a country in Oceania that hosts unique rain forests and forest ecosystems which are crucial for sequestering atmospheric carbon, conserving biodiversity, supporting the livelihood of indigenous people, and underpinning the timber market of the country. As a result of urban sprawl, agricultural expansion, and illegal logging, there has been a tremendous increase in land-use land cover (LULC) change happening in the country in the past few decades and this has triggered massive deforestation and forest degradation. However, only a few studies have ventured into quantifying the long-term trends and their associated spatial patterns—and have often presented contrasting responses. Herein, we intended to assess the extent of deforestation and the rate of urbanization that happened in the past 33 years (1987–2020) in the Bumbu river basin in Papua New Guinea using satellite imagery—for the years 1987, 2002, 2010, and 2020—and Geographic Information System (GIS) tools. On performing image classification, land use maps were developed and later compared with Google Earth’s high-resolution satellite images for accuracy assessment purposes. For probing into the spatial aspects of the land-use change issues, the study area was divided into four urban zones and four forest zones according to the four main cardinal directions centered in the urban and forest area centers of the 1987 image; subsequently, the rate of urban area expansion in each urban zone was separately calculated. From our preliminary analysis and literature survey, we observed several hurdles regarding the classification of regenerative forests and mixed pixels and gaps in LULC studies that have happened in Papua New Guinea to date. Through this communication paper, we aim to disseminate our preliminary results, which highlight a rapid increase in urban extent from 14.39 km2 in 1987 to 23.06 km2 in 2020 accompanied by a considerable decrease in forest extent from 76.29 km2 in 1987 to 59.43 km2 in 2020; this observation favors the presumption that urban and agricultural land expansion is happening at the cost of forest cover. Moreover, strategies for addressing technical issues and for integrating land-use change with various socioeconomic and environmental variables are presented soliciting feedback.

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Sam, Katerina, Richard Ctvrtecka, Scott E. Miller, Margaret E. Rosati, Kenneth Molem, Kipiro Damas, Bradley Gewa e Vojtech Novotny. "Low host specificity and abundance of frugivorous lepidoptera in the lowland rain forests of Papua New Guinea". PLOS ONE 12, n. 2 (23 febbraio 2017): e0171843. http://dx.doi.org/10.1371/journal.pone.0171843.

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Più fonti

Tesi sul tema "Rain forests – Papua New Guinea"

Abe, Hitofumi. "Forest management impacts on growth, diversity and nutrient cycling of lowland tropical rainforest and plantations, Papua New Guinea". University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0098.

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[Truncated abstract] Globally, tropical rainforests are noted for their high biodiversity and key roles in carbon storage and influence on climate. Nevertheless, tropical deforestation in many parts of the world continues at an alarming rate. In Papua New Guinea (PNG), tropical rainforest is relatively well maintained, with about 70 % of the land area still covered by primary forest. However, PNG's native forests are coming under increasing pressure, particularly from selective logging for high quality timber. While the forests of PNG, and more broadly the entire New Guinea Island, are recognised as of high conservation and ecological significance, they remain grossly understudied with little knowledge of key ecosystem processes within lowland forests in particular. Such knowledge is urgently required if the impacts of logging and other land-use change are to be assessed and in order to develop sustainable management systems. This thesis investigated the impacts of logging on diversity and nutrient cycling in a lowland tropical rainforest growing on limestone soils in the area of the Mongi-Busiga Forest Management Agreement (FMA, which is a logging concession area), in northeastern PNG. These forests are on relatively young soils and provide a useful contrast to the majority of tropical forests. The research includes a four-year study of the recovery of diversity and structure after logging, and quantified forest structure, tree species diversity, forest biomass and productivity, and nutrient distribution and cycling. This thesis also examines the ecological sustainability of Eucalyptus deglupta plantations in Wasab, PNG as an alternative resource for timber and biomass energy. The thesis concludes with a discussion of long-term forest recovery and sustainable forest management in north-eastern PNG. Two adjacent one-hectare plots were established in lowland tropical rainforest at Mongi-Busiga FMA. One of these plots was subsequently selectively logged, one year after establishment. Before logging, the two one-hectare plots contained a total of 37 families, 70 genera and 110 tree species that were >5 cm in diameter at breast height. Mean basal area was 42.4 m2 ha-1. Two tree species, Madhuca leucodermis (Sapotaceae) and Pometia pinnata (Sapindaceae) accounted for ~60% of the total basal area. Gymnacranthera paniculata (Myristicaceae) was the most common species and accounted for 13% of individuals. ... This study concludes that the Mongi-Busiga forest has many unusual characteristics for a tropical forest, including relatively low diversity of tree species, high accumulation of P in the biomass, and N limitations, compared to other tropical rainforests. However, those extraordinary characteristics may be explained well by the underlying geology of young, marine-derived limestone. Sustainable management of the lowland tropical forests of PNG should consider the consequences of logging on nutrient cycling processes, with the possible significant removal of P from site with repeated logging, as well as the interactions between N and P in these systems. Establishment of Eucalyptus plantations on previously cleared land also has the potential to meet some of the timber and biomass energy requirements of northern PNG in ecologically sustainable manner.

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Saulei, Simon M. "The recovery of tropical lowland rainforest after clearfell logging in the Gogol Valley, Papua New Guinea". Thesis, University of Aberdeen, 1985. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU363256.

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Recovery of tropical rain forest in Gogol Valley, Papua New Guinea was monitored for 2 years following clear-fel1ing in the wet and dry seasons. Further redevelopment, reconstructed by measurements of regrowth of known ages from 1.5-10.8 years, were compared with forest heavily disturbed by fire 55 years ago and primary forest. The vegetation, survey was assessed principally by Counting and measuring trees. Because of the importance of soil seed bank in influencing vegetation recovery processes, special attention was given to the spatial and temporal changes in the soil seed bank and the seed rain which supplies it. The major findings were: (1) vegetation recovery was rapid and 97% of all colonizing trees regenerated from seeds while 3% were resprouts; (2) regrowth after felling in the dry-season differed from that following wet-season felling in having lower density, slower growth and mostly comprised resprouting tree species; (3) after 10 years, regrowth is composed principally of large pioneer trees (65% of basal area or 64% of stems); (4) the 55 year-old forest also had many (48%) pioneer trees: much of the forest in the area is of this kind and may be classified as advanced secondary forest; (5) forest soil seed bank following felling was rapidly depleted due to germination, but was rapidly replaced as early pioneer herbs matured and set seed. Trees in soil seed bank do not approach that of primary forest until after 10 years of regrowth; (6) the intensity of pioneer trees' seed rain was correlated with the fecundity of nearby parent trees and clearly controlled soil seed bank redevelopment. There was evidence of dispersal of pioneer seeds several hundred metres into an isolated area of closed forest; (7) trees left uncut following felling contribute significantly to seed rain and therefore to soil seed bank.

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Nir, Edward Ess. "The monodominant stands of anisoptera thurifera ssp polyandra and their management in Papua New Guinea /". [St. Lucia, Qld], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18255.pdf.

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VLAŠÁNEK, Petr. "Population structure and dispersal of butterflies in tropical rain forests of Papua New Guinea". Doctoral thesis, 2013. http://www.nusl.cz/ntk/nusl-161356.

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The thesis describes the community composition, population structure and dispersal in a lowland rainforest community, extended to changes in butterfly composition along an altitudinal gradient. It tests the feasibility of mark-release-recapture studies in the understories of lowland primary forests, describes dispersal in relation to host plants and compares dispersal and demographic parameters with temperate species. Focusing on primary as well as secondary sites the thesis analyzes species richness and similarity between sites along an altitudinal gradient. It also tests ecological correlates for endemism in New Guinea butterflies, particularly their geographic and altitudinal range, as well as their optimum altitude.

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ČTVRTEČKA, Richard. "Host specificity and species diversity in communities of frugivorous insect in lowland rain forest of Papua New Guinea". Doctoral thesis, 2014. http://www.nusl.cz/ntk/nusl-180642.

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The thesis describes host specificity and species diversity in communities of frugivorous insect in lowland rain forest of Papua New Guinea. It focuses separately on weevils and Lepidoptera, as main groups of frugivores. Further, it focuses on fruit morphology and the structure of frugivorous communities.

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Nemitz, Dirk. "Bewertung der Erfassungswahrscheinlichkeit für globales Biodiversitäts-Monitoring: Ergebnisse von Sampling GRIDs aus unterschiedlichen klimatischen Regionen". Master's thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0022-5F99-F.

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Libri sul tema "Rain forests – Papua New Guinea"

Grubb, P. J. The forests of the Fatima basin and Mt. Kerigomna, Papua New Guinea, with a review of montane and subalpine rainforests in Papuasia. Canberra: Australian National University, 1985.

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Grubb, P. J. The forests of the Fatima basin and Mt. Kerigomna,Papua New Guinea, with a review of montane and subalpine rainforests in Papuasia. Canberra: Australian National University, 1985.

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Hayano, David M. Road through the rain forest: Living anthropology in highland Papua New Guinea. Prospect Heights, Ill: Waveland Press, 1990.

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Novotny, Vojtech. Notebooks from New Guinea: Field notes of a tropical biologist. Oxford: Oxford University Press, 2009.

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Exploiting the tropical rain forest: An account of pulpwood logging in Papua New Guinea. Paris: U.N.E.S.C.O., 1990.

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Ancestral rain forests and the mountain of gold: Indigenous peoples and mining in New Guinea. Boulder: Westview Press, 1994.

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Nikhil, Sekhran, a cura di. Race for the rainforest: Evaluating lessons from an integrated conservation and development "experiment" in New Ireland, Papua New Guinea. Waigani, Papua New Guinea: PNG Biodiversity Conservation and Resource Management Programme, 1997.

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Kaufmann, Christian. Korewori: Magic art from the rain forest : a unique collection of wood sculptures from Papua New Guinea. Basel: Museum der Kulturen, 2003.

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Ancestral lines: The Maisin of Papua New Guinea and the fate of the rainforest. Peterborough, Ont: Broadview Press, 2008.

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Ellis, Julie-Ann. Race for the rainforest II: Applying lessons learned from Lak to the Bismarck-Ramu Integrated Conservation and Development Initiative in Papua New Guinea. Waigani: PNG Biodiversity Conservation and Resource Management Programme, 1997.

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Capitoli di libri sul tema "Rain forests – Papua New Guinea"

Collins, N. Mark, Jeffrey A. Sayer e Timothy C. Whitmore. "Papua New Guinea". In The Conservation Atlas of Tropical Forests Asia and the Pacific, 174–82. London: Palgrave Macmillan UK, 1991. http://dx.doi.org/10.1007/978-1-349-12030-7_21.

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Corlett, Richard T. "Vegetation". In The Physical Geography of Southeast Asia. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780199248025.003.0017.

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Southeast Asia is not a natural biogeographical unit: it extends well north out of the tropics in Myanmar, while the eastern boundary bisects the island of New Guinea. It is also divided in two by one of the sharpest zoogeographical boundaries in the world, Wallace’s line (Figure 7.1; Whitmore 1987). There is, however, one important unifying feature that distinguishes it from most other regions of the tropics: Southeast Asia is a region of forest climates. Only on the highest mountains in Papua and northern Myanmar is the climate too cold for forest and, with the possible exception of some small rain-shadow areas, it is nowhere too dry. Elsewhere the only permanent non-forest vegetation in the region before the human impacts of the last few millennia was on coastal cliffs and beaches, seasonally flooded river plains, active volcanoes, and perhaps some small inland areas on soils too poor to support forest. Today, however, as a result of human impacts, forest occupies less than half of the region, with various anthropogenic vegetation types occupying the rest. The recognition of Southeast Asia, as defined here, as a separate political and geographic entity is very recent, so it is not surprising that there has been no previous account of the vegetation of the whole region. Van Steenis (1957) gave a general account of the vegetation of Indonesia, while Whitmore (1984) concentrated on the tropical evergreen forests of the region, with only a brief description of the vegetation of drier climates. Champion (1936) described the principal forest types of Myanmar, while Vidal (1997) covered the vegetation of Thailand, Cambodia, and Lao PDR. Numerous other publications describe smaller areas or specific vegetation types. To a first approximation, the potential natural vegetation of the region (Plate 1) up to about 20°N is controlled by two main environmental gradients: a horizontal gradient of water availability and a vertical, altitudinal gradient. Water availability is determined largely by the amount and distribution of rainfall, with the length of the dry season the most important factor, although the water storage capacity of the soil becomes increasingly significant at the drier end of the gradient.

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"The Money Rain Phenomenon: Papua New Guinea Oil and the Resource Curse". In Natural Resource Extraction and Indigenous Livelihoods, 90–108. Routledge, 2016. http://dx.doi.org/10.4324/9781315597546-8.

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West, Paige, e Enock Kale. "The Fate of Crater Mountain: Forest Conservation in the Eastern Highlands of Papua New Guinea". In Tropical Forests Of Oceania: Anthropological Perspectives. ANU Press, 2015. http://dx.doi.org/10.22459/tfo.08.2015.07.

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"What Local People Want with Forests: Ideologies and Attitudes in Papua New Guinea". In Natural Resource Extraction and Indigenous Livelihoods, 217–36. Routledge, 2016. http://dx.doi.org/10.4324/9781315597546-14.

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Wood, Michael. "Representational Excess in Recent Attempts to Acquire Forest Carbon in the Kamula Doso Area, Western Province, Papua New Guinea". In Tropical Forests Of Oceania: Anthropological Perspectives. ANU Press, 2015. http://dx.doi.org/10.22459/tfo.08.2015.09.

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Bayliss-Smith, Tim, Jack Golson e Philip Hughes. "Phase 5: Retreating Forests, Flat-Bottomed Ditches and Raised Fields". In Ten Thousand Years of Cultivation at Kuk Swamp in the Highlands of Papua New Guinea. ANU Press, 2017. http://dx.doi.org/10.22459/ta46.07.2017.15.

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Juo, Anthony S. R., e Kathrin Franzluebbers. "Properties and Management of Allophanic Soils". In Tropical Soils. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195115987.003.0017.

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Allophanic soils are dark-colored young soils derived mainly from volcanic ash. These soils typically have a low bulk density (< 0.9 Mg/m3), a high water retention capacity (100% by weight at field capacity), and contain predominantly allophanes, imogolite, halloysite, and amorphous Al silicates in the clay fraction. These soils are found in small, restricted areas with volcanic activity. Worldwide, there are about 120 million ha of allophanic soils, which is about 1% of the Earth's ice-free land surface. In tropical regions, allophanic soils are among the most productive and intensively used agricultural soils. They occur in the Philippines, Indonesia, Papua New Guinea, the Caribbean and South Pacific islands, East Africa, Central America, and the Andean rim of South America. Allophanic soils are primarily Andisols and andic Inceptisols, Entisols, Mollisols, and Alfisols according to the Soil Taxonomy classification. Allophanic soils generally have a dark-colored surface soil, slippery or greasy consistency, a predominantly crumb and granular structure, and a low bulk density ranging from 0.3 to 0.8 Mg/m3. Although allophanic soils are apparently well-drained, they still have a very high water content many days after rain. When the soil is pressed between fingers, it gives a plastic, greasy, but non-sticky sensation of a silty or loamy texture. When dry, the soil loses its greasiness and becomes friable and powdery. The low bulk density of allophanic soils is closely related to the high soil porosity. For example, moderately weathered allophanic soils typically have a total porosity of 78%, with macro-, meso-, and micropores occupying 13%, 33%, and 32%, respectively. Water retained in the mesopores is readily available for plant uptake. Water retained in the micropores is held strongly by soil particles and is not readily available for plant use. The macropores provide soil aeration and facilitate water infiltration. The high water retention capacity is also associated with the high soil porosity. In allophanic soils formed under a humid climate, especially those containing large amounts of allophane, the moisture content at field capacity can be as high as 300%, calculated on a weight basis. Such extremely high values of water content seem misleading.

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Atti di convegni sul tema "Rain forests – Papua New Guinea"

Eastment, J. D. "Rain radar measurements in Papua New Guinea and their implications for slant path propagation". In IEE Colloquium on Remote Sensing of the Propagation Environment. IEE, 1996. http://dx.doi.org/10.1049/ic:19961182.

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