Progress of Crop in Some Rhizophora Stands before First Thinning in Matang Mangrove Reserve of Peninsular Malaysia

The study reports the composition and growth pattern of the crops dominated by Rhizophora species in terms of stocking density, diameter and height growth in some well-managed stands in Matang Mangrove Reserve of Peninsular Malaysia. In all, 10 stands representing 6 years (4), 9 years (3) and 12 years (3) were studied. On an average there were 8371,4661 and 4181 stems/ha of Rhizophora in 6, 9 and 12 year-old crops respectively. Mean DBH and height for the respective age crops were 3.26 cm and 6.34 m, 5.50 cm and 10.96 m and 6.91 cm and 12.62 m. Highest mortalityoccu"edin 6-9 year-old crop. This period also showed best growth both in diameter and height. These studies indicate the need for silvicultural thinning in 6- 9 year-old crop. The climber Derris trifoliata may seriously affect growth and survival in some areas

Molecular dynamics simulations and photoluminescence measurements of annealed ZnO surfaces

The effect of thermal annealing on wurtzite ZnO, terminated by two surfaces, (0 0 0 $\bar 1$) (which is oxygen-terminated) and (0 0 0 1) (which is Zn-terminated), is investigated via molecular dynamics simulation using reactive force field (ReaxFF). As a result of annealing at a threshold temperature range of 700~K < T_{\mbox{\small t}} \leq 800~K, surface oxygen atoms begin to sublimate from the (0 0 0 $\bar 1$) surface, while no atom leaves the (0 0 0 1) surface. The ratio of oxygen leaving the surface increases with temperature $T$ (for T \geq T_{\mbox{\small t}}). The relative luminescence intensity of the secondary peak in the photoluminescence (PL) spectra, interpreted as a measurement of amount of vacancies on the sample surfaces, qualitatively agrees with the threshold behavior as found in the MD simulations. Our simulations have also revealed the formation of oxygen dimers on the surface and evolution of partial charge distribution during the annealing process. Our MD simulation based on the ReaxFF is consistent with experimental observations.Comment: 26 pages, 11 figures. Manuscript submitted to Physica

Spatiotemporal changes in biomass after selective logging in a lowland tropical rainforest in peninsular Malaysia

We studied biomass changes in a lowland tropical rain forest in the Pasoh Forest Reserve of Peninsular Malaysia after selective logging in 1958. A tree census was undertaken every 2 years from 1998 to 2012 in a 6-ha logged forest plot. Total aboveground biomass (AGB) was 72 % of that in a primary forest plot within the same reserve in 1998, but reached 87 % in 2012. AGB regrowth was spatially variable within the logged forest plot and was much less in swampy areas than in upland areas. The overall annual growth rate of AGB in the logged forest throughout the study period was 1.5 % and slowed (to 0.6 %) in a dry period (2004-2006). The biomass of large trees (DBH ≥ 50 cm) increased by 56 % during the study period, but amounted to only 58 % of the biomass of the corresponding size class in the primary forest, suggesting that stand structure is still recovering from logging. Spatiotemporal variation in AGB recovery after logging needs to be taken into account for logging and subsequent management of the tropical lowland forest biome

A multi-stakeholder strategy to identify conservation priorities in Peninsular Malaysia

Malaysia, with its rapidly growing economy, exemplifies the tensions between conservation and development faced by many tropical nations. Here we present the results of a multi-stakeholder engagement exercise conducted to (1) define conservation priorities in Peninsular Malaysia and (2) explore differences in perceptions among and within stakeholder groups (i.e. government, academia, NGOs and the private sector). Our data collection involved two workshops and two online surveys where participants identified seven general conservation themes and ranked the top five priority issues within each theme. The themes were: (1) policy and management, (2) legislation and enforcement, (3) finance and resource allocation, (4) knowledge, research and development, (5) socio-economic issues, (6) public awareness and participation and (7) rights of nature. In spite of their very different backgrounds and agendas, the four stakeholder groups showed general agreement in their priority preferences except for two issues. Respondents from government and private sector differed the most from each other in their priority choices while academia and NGO showed the highest degree of similarity. This ranked list of 35 conservation priorities is expected to influence the work of policy-makers and others in Peninsular Malaysia and can be used as a model to identify conservation priorities elsewhere

A New Species of Licuala (Palmae) from Peninsular Malaysia

Volume: 42Start Page: 71End Page: 7

Canopy height recovery after selective logging in a lowland tropical rain forest

The effects of selective logging on canopy height were studied in a lowland tropical rain forest in Pasoh Forest Reserve, Peninsular Malaysia. Canopy height was measured in 2003 and 2011 by using an airborne light detection and ranging system and mapped on a 2.5-m grid over logged and primary forest plots. The logged forest plot was in an area where a selective logging operation had been conducted in 1958, whereas the primary forest plot has no trace of any major human-induced disturbances. The average canopy height in the logged forest plot increased from 23.6 m (2003) to 25.8 m (2011), but both of these heights were still significantly lower (P < 0.0001) than in those in the primary forest plot (28.7 m in 2003 and 30.4 m in 2011). The coefficient of variation and canopy height diversity (H′) were also lower in the logged forest plot, suggesting that the highly heterogeneous canopy height commonly seen in the primary forest in this region had not fully recovered even 53 years after the logging operation. Simulation analysis revealed that it will take at least another 16 years from the last canopy mapping (2011) for full recovery

Historical distribution of Sundaland's Dipterocarp rainforests at Quaternary glacial maxima.

The extent of Dipterocarp rainforests on the emergent Sundaland landmass in Southeast Asia during Quaternary glaciations remains a key question. A better understanding of the biogeographic history of Sundaland could help explain current patterns of biodiversity and support the development of effective forest conservation strategies. Dipterocarpaceae trees dominate the rainforests of Sundaland, and their distributions serve as a proxy for rainforest extent. We used species distribution models (SDMs) of 317 Dipterocarp species to estimate the geographic extent of appropriate climatic conditions for rainforest on Sundaland at the last glacial maximum (LGM). The SDMs suggest that the climate of central Sundaland at the LGM was suitable to sustain Dipterocarp rainforest, and that the presence of a previously suggested transequatorial savannah corridor at that time is unlikely. Our findings are supported by palynologic evidence, dynamic vegetation models, extant mammal and termite communities, vascular plant fatty acid stable isotopic compositions, and stable carbon isotopic compositions of cave guano profiles. Although Dipterocarp species richness was generally lower at the LGM, areas of high species richness were mostly found off the current islands and on the emergent Sunda Shelf, indicating substantial species migration and mixing during the transitions between the Quaternary glacial maxima and warm periods such as the present

(a) XPS Ni 2p regional scan.

<p>(b) O 1s regional scan. (c) Zn 2p regional scan.</p

Species limits, geographical distribution and genetic diversity in Johannesteijsmannia (Arecaceae)

10.1111/boj.12470BOTANICAL JOURNAL OF THE LINNEAN SOCIETY1822318-34

XRD patterns of the Ni contact on (a) Zn-polar surface before annealing; (b) Zn-polar surface after annealing; (c) O-polar surface before annealing; (d) O-polar surface after annealing.

<p>XRD patterns of the Ni contact on (a) Zn-polar surface before annealing; (b) Zn-polar surface after annealing; (c) O-polar surface before annealing; (d) O-polar surface after annealing.</p