808 resultados para Malaysia Today
Resumo:
The spatial distributions of species of tree ≥10 cm gbh were examined in two 4 ha plots and related to the local variation in topography and soil chemistry. The plots were similar in their species composition, particularly in terms of the densities of small trees, and they showed very similar edaphic characteristics. Size class distributions varied little within and between plots. Ordination of 0.25 ha subplots highlighted parallel gradients in the vegetation of both plots when the densities of trees ≥10 cm gbh were considered. Focusing on understorey trees in the 10-<50 cm gbh class at the 0.04 ha subplot scale showed a similar vegetation gradient in both plots closely associated with change from lower slope to ridge. No relationship with soil chemistry was found. On the ridges a special group of understorey species formed clumps and these species contributed importantly to the ordinations. Borneo has a regional history of occasionally severe droughts. It is suggested here that the observed patterns in the understorey are due to differential responses to low soil water supply, the ridges probably tending to dryness more than the lower slopes. Within the large and diverse family Euphorbiaceae, which dominates the understorey at Danum, there may be ecophysiological groupings of species. The long-term effects of disturbance interacting with local edaphic factors on forest structure and composition are discussed.
Resumo:
Changes in species composition in two 4–ha plots of lowland dipterocarp rainforest at Danum, Sabah, were measured over ten years (1986 to 1996) for trees greater than or equal to 10 cm girth at breast height (gbh). Each included a lower–slope to ridge gradient. The period lay between two drought events of moderate intensity but the forest showed no large lasting responses, suggesting that its species were well adapted to this regime. Mortality and recruitment rates were not unusual in global or regional comparisons. The forest continued to aggrade from its relatively (for Sabah) low basal area in 1986 and, together with the very open upper canopy structure and an abundance of lianas, this suggests a forest in a late stage of recovery from a major disturbance, yet one continually affected by smaller recent setbacks. Mortality and recruitment rates were not related to population size in 1986, but across subplots recruitment was positively correlated with the density and basal area of small trees (10 to <50 cm gbh) forming the dense understorey. Neither rate was related to topography. While species with larger mean gbh had greater relative growth rates (rgr) than smaller ones, subplot mean recruitment rates were correlated with rgr among small trees. Separating understorey species (typically the Euphorbiaceae) from the overstorey (Dipterocarpaceae) showed marked differences in change in mortality with increasing gbh: in the former it increased, in the latter it decreased. Forest processes are centred on this understorey quasi–stratum. The two replicate plots showed a high correspondence in the mortality, recruitment, population changes and growth rates of small trees for the 49 most abundant species in common to both. Overstorey species had higher rgrs than understorey ones, but both showed considerable ranges in mortality and recruitment rates. The supposed trade–off in traits, viz slower rgr, shade tolerance and lower population turnover in the understorey group versus faster potential growth rate, high light responsiveness and high turnover in the overstorey group, was only partly met, as some understorey species were also very dynamic. The forest at Danum, under such a disturbance–recovery regime, can be viewed as having a dynamic equilibrium in functional and structural terms. A second trade–off in shade–tolerance versus drought–tolerance is suggested for among the understorey species. A two–storey (or vertical component) model is proposed where the understorey–overstorey species’ ratio of small stems (currently 2:1) is maintained by a major feedback process. The understorey appears to be an important part of this forest, giving resilience against drought and protecting the overstorey saplings in the long term. This view could be valuable for understanding forest responses to climate change where drought frequency in Borneo is predicted to intensify in the coming decades.
Resumo:
"Simmel and Freudian Philosophy" (GS 5, S. 396-405); 1. Nachruf, verlesen beim Memorial Meeting for Ernst Simmel; datiert: 13.12.1947; veröffentlicht in: International Journal of Psychoanalysis, 29. Jahrgang, 1948, S. 110-113; 2. Abschrift aus Werken und Briefen Siegmund Freuds; Typoskript, 9 Blatt; 3. Freeman, Burriel: 1 Brief mit Unterschirft an Max Horkheimer, Chicago, 10.06.1949; 1 Brief von Max Horkheimer, Los Angeles, 15.06.1949, 2 Blatt; "Authoritarianism and the Family Today" (GS 5, S. 377-395); 1. Aufsatz, datiert 1947, veröffentlicht in: Ruth Nanda Anshen (editor), "The Family: Its Function and Distiny", New York 1949. a) Typsokript, 20 Blatt b) Typoskript mit handschriftlichen Korrekturen, 20 Blatt c) Typoskript mit eigenhändigen Korrekturen, 20 Blatt d)-f) deutsche Fassung mit dem Titel "Autorität und Familie", übersetzt vom Institut für Sozialforschung, 1960; veröffentlicht in : "Erkenntnis und Verantwortung. Festschrift für Theodor Litt", Düsseldorft, 1960 d) Typoskript, 20 Blatt e) Typoskript, 20 Blatt f) Korrekturfahnen aus der Litt- Festschrift, mit dem Titel "Autorität und Familie in der Gegenwart"; 6 Blatt; 2. Schönbach, Peter: 1 Brief mit Unterschrift an Max Horkheier, ohne Ort, 23.06.1960; 1 Blatt; 3. Schönbach, Peter: 1 Brief mit Unterschrift an Friedrich Pollock, ohne Ort, 22.06.1960; 1 Blatt; "The Chances of Democracy in Germany" (GS 12, S. 184-194); 1947 [?] a) Typoskript, 10 Blatt b) Typoskript mit eigenhändigen Korrekturen, 11 Blatt c) Typoskript mit eigenhändigen Korrekturen ,11 Blatt;
Resumo:
The Central gold belt of peninsular Malaysia comprises a number of gold deposits located in the east of the N-S striking Bentong-Raub Suture Zone. The Tersang gold deposit is one of the gold deposits in the gold belt and hosted in sandstone, rhyolite and breccia units. The deposit has an inferred resource of 528,000 ounces of gold. The geochronology of the Tersang deposit has been newly constrained by LA ICP-MS U-Pb zircon dating. The maximum depositional age of the host sedimentary rocks ranges from Early Carboniferous to Early Permian (261.5 ± 4.9 Ma to 333.5 ± 2.5 Ma) for the host sandstone and Late Triassic for the rhyolite intrusion (218.8 ± 1.7 Ma). Textural characteristics of pyrite have revealed five types including (1) Euhedral to subhedral pyrite with internal fracturing and porous cores located in the sandstone layers (pyrite 1); (2) Anhedral pyrite overgrowths on pyrite 1 and disseminated in stage 1 vein (pyrite 2); (3) Fracture-filled or vein pyrite located in stages 1 and 2 vein (pyrite 3); (4) Euhedral pyrite with internal fractures also located in stage 2 vein (pyrite 4); and (5) Subhedral clean pyrite located in the rhyolite intrusion (pyrite 5). Based on pyrite mapping and spot analyses, two main stages of gold enrichment are documented from the Tersang gold deposit. Gold in sandstone-hosted pyrite 1 (mean 4.3 ppm) shows best correlation with Bi and Pb (as evidenced on pyrite maps). In addition, gold in pyrite 3 (mean 8 ppm) located in stage 2 vein shows a good correlation with As, Ag, Sb, Cu, Tl, and Pb. In terms of gold exploration, we suggest that elements such as As, Ag, Sb, Cu, Tl, Bi, and Pb associated with Au may serve as vectoring tools in gold exploration. Our new geological, structural, geochemical and isotopic data together with mineral paragenesis, pyrite chemistry and ore fluid characteristics indicate that the Tersang gold deposit is comparable to a sediment-hosted gold deposit. Our new genetic model suggests deposition of the Permo-Carboniferous sediments followed by intrusion of rhyolitic magma in the Late Triassic. At a later stage, gold mineralisation overprinted the rhyolite intrusion and the sandstone.
Resumo:
Fil: Peretó Rivas, Rubén.
Resumo:
Fil: Chá, Rita Teresita. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.