Ecophysiological responses of two tropical urban shrub plants to elevated carbon dioxide and water stress

Elevated atmospheric carbon dioxide causes changes in most plant species in terms of physiological and morphological properties. In this study, we elucidate the effects of elevated CO2 and water regimes on two species of shrubs which were Melastoma malabathricum and Clidemia hirta. The factor of water stress was also included whereby for each CO2 treatment, the amount of water was given once or twice daily. The treatment of elevated CO2 was at 800 ppm, where the plants were exposed for two hours daily and ambient CO2 at 400 ppm as the control. The growth of plants was monitored through their height, leaf area and biomass that were recorded fortnightly for six months. The physiological changes were determined via stomatal conductance, photosynthetic rate and transpiration rate. The results revealed that each species responded differently to the CO2 treatments. The growth parameters of height and leaf area index showed positive responses on elevated CO2 and twice watering for both species. As for biomass, M. malabathricum exhibited higher below ground biomass compared to above ground biomass in the elevated CO2. In contrast, C. hirta showed the opposite trend. The results of the three physiological parameters demonstrated a bell shape trend for both treatments with the highest rate at the fifth month

Penentuan tahap kelangkaan spesies tumbuhan hutan tropika sebagai langkah pemuliharaan di Rizab Biosfera UNESCO Malaysia

Pemuliharaan spesies tumbuhan tropika biasanya terhad kepada faktor taburan spesies di peringkat rantau Asia Tenggara tanpa mengambil kira faktor julat geografi setempat, limitasi taburan spesies kepada julat habitat yang khusus dan saiz populasi di peringkat landskap. Kajian ini melibatkan perbandingan kelangkaan spesies tumbuhan di tiga zon pengurusan Rizab Biosfera Tasik Chini (TCBR), Pahang. Tahap kelangkaan spesies dikelaskan kepada lapan sel (A–H) berdasarkan Skim Rabinowitz. Penentuan spesies yang endemik turut dilakukan berdasarkan Turner. Kajian merekodkan 771 spesies tumbuhan di TCBR. Sejumlah 600 spesies (77.8%) direkodkan sebagai spesies langka (Sel B–H) manakala selebihnya (22.2%) adalah spesies yang biasa ditemui (Sel A). Spesies yang paling langka (Sel H, 49.3%) adalah spesies dengan geografi yang terbatas, habitat yang khusus dan saiz populasi yang kecil. Sejumlah 20 spesies tumbuhan direkodkan sebagai spesies endemik. Dua daripada 20 spesies endemik tersebut ialah spesies yang biasa ditemui berdasarkan Skim Rabinowitz. Manakala, empat spesies endemik merupakan spesies langka yang mempunyai julat geografi yang meluas tetapi mempunyai habitat dan saiz populasi yang terhad (Sel D) dan 14 spesies endemik selebihnya ialah spesies yang paling langka (Sel H). Lebih kurang 76% spesies yang tidak endemik tetapi termasuk dalam kategori spesies langka. Kajian ini memberi penunjuk bahawa usaha pemuliharaan spesies pada peringkat landskap seperti TCBR perlu turut mengambil kira tahap kelangkaan setempat di samping faktor taburan spesies pada peringkat serantau

Structural and floristic pattern in a disturbed mangrove tropical swamp forest: a case study from the Langkawi UNESCO Global Geopark Forest, Peninsular Malaysia

Forest structure, diversity and above-ground biomass assessment are important to understand the structural and floristic dynamics of a mangrove forest ecosystem. Our study provides valuable comparative analysis between two areas of disturbed mangroves at Kisap Forest Reserve, Langkawi Island. The two study sites were swamp forest at C5 which was disrupted by harvesting activities for charcoal production and C7 was disturbed by lightning strikes. A total of 1,217 and 390 trees measuring 1 cm diameter and above were enumerated in 0.25 ha plots at both sites. Seven mangrove plant species in C5 and eight in C7 were recorded. Ceriops tagal and Rhizophora apiculata were the most prominent species in the C5 and C7, respectively, whereby the Rhizophoraceae was the densest family at both sites. The major contributor of total basal area at C5 and C7 were C. tagal (5.02 m2/ha) and R. apiculata (11.14 m2/ha). Similarly, C. tagal (22.41 t/ha) and R. apiculata (111.75 t/ha) also contributed the highest biomass in C5 and C7, respectively. Diversity and species richness were higher at C7 H’=1.22; R’=1.17 compared to C5 H’= 0.76; R’=0.85 and low evenness at both sites. High similarity was indicated between the two sites by 93%. The distribution of individuals in C7 was homogenous than that of C5, which had more saplings. In conclusion, anthropogenic activities resulted in lower productivity of forest compared to natural disturbances

Lecturer’s perception on the implementation of Problem-Based Learning (PBL) approach in teaching and learning

Problem-based learning (PBL) was known as the student-centered pedagogy where it involves the student to experience solving complex real-world problems and the teacher acts as a facilitator in crafting trigger materials to promote the learning concepts. This study aims to investigate and identify the level of usefulness and challenges as well as the level of student achievement through the perception of academic staff’ on the implementation of PBL in classrooms in Malaysia. A quantitative study was conducted, and the data was collected through a survey questionnaire on 98 lecturers all over Malaysia. The findings from the analysis indicate that lectures in Malaysia have a high perception of PBL implementation in the classroom. Overall, the findings enhance the understanding of higher institution lecturers’ perception of PBL in terms of the usefulness of PBL as one dynamic and active approach that transforms dramatically the routine lecture-based learning. Findings also suggest that sufficient training to learners is required in implementing PBL effectively, thus indirectly facilitate the focus of students that lead to the achievement of course learning outcomes

Effects of elevated atmospheric CO2 on photosynthesis, growth and biomass in Shorea platycarpa F. Heim (Meranti Paya)

Elevated atmospheric CO2 is widely reported to stimulate the plant growth and affect plant physiological processes. However, studies on the respond of tropical plant species to elevated CO2 are quite limited and remain largely unknown. The objective of this study was to investigate the effects of elevated atmospheric CO2 treatments on the photosynthetic characteristics, growth and biomass in Shorea platycarpa. Saplings of S. platycarpa were grown for seven months in the open roof gas chamber supplied with elevated CO2 (800±50 μmol mol-1) and in the shade house with ambient CO2 (400±50 μmol mol-1). Measurements of S. platycarpa growth and photosynthetic characteristics were made at frequent intervals. Biomass characteristics were determined using destructive methods after seven months of treatment and nondestructive method was used for leaf area index (LAI) determination. Photosynthetic rate (A) of S. platycarpa was not significantly affected by elevated CO2. Increased water use efficiency (WUE) of S. platycarpa grown in elevated CO2 was due to the reduced stomatal conductance (gs) and transpiration rate (E). The CO2 elevation had no significant effect on the S. platycarpa relative growth rates (RGR) and biomass but significantly reduced the leaf area. A weak correlation was found between photosynthetic rate (A) and relative growth rate (RGR). The results clearly showed that photosynthesis, growth rate and biomass of S. platycarpa were not significantly enhanced by elevated CO2. The findings indicated that elevated CO2 did not affect a relatively slow growing and a late successional peat swamp tree species

Allelopathic potential of the leaf and seed of Pueraria javanica Benth. on the germination and growth of three selected weed species

Pueraria javanica Benth. is one of the most common leguminous cover crop used in oil palm plantations of Malaysia. A study was conducted to determine the allelopathic potential of this plant, using the aqueous extract, sandwich and dish-pack methods, with the seed and leaf (of P. javanica) on three bioassay weed species namely, Eleusine indica, Cyperus iria and Chromolaena odorata. The aqueous extract experiment was conducted using 0 (control), 16.7, 33.3 and 66.7 g/L of the aqueous leaf and seed extracts while the sandwich method was carried out using 10 and 50 mg of each of the donour plant parts. Meanwhile, the dish-pack method was done using four different distances (41, 58, 82 and 92 mm) away from the donour plant. All experiments were replicated five times using the complete randomized design (CRD). The leaf extract exhibited 100% reduction on the fresh weight of E. indica and C. odorata while the seed extract exhibited 100% reduction on all parameters for E. indica and on the fresh weight of C. iria at 66.7 g/L concentration. The seed and leaf at 10 and 50 mg significantly reduced the radicle length of all the bioassay species. The dish-pack experiment also showed a reduction effect on the germination percentage and seedling growth parameters of all the bioassay species. However, the reduction effect was not totally in accordance to the distance from the donor species. More studies need to be conducted to determine the type of reduction mechanism involved in the allelopathic activity especially with respect to molecular and biochemical aspects

Determinants of Family Takaful (Islamic Life Insurance) Demand: A Conceptual Framework for a Malaysian Study

Family Takaful is one of the service sectors that are expected to continue to drive growth in the economy.Thus, the family Takaful market continues to play an important role in supporting economic and social development.However, in Malaysia, family Takaful market is still at a lower penetration level if we were to compare to other developed countries even though the Takaful industry continues to sustain strong performance amidst challenges in a competitive environment.Evidence has shown that the percentage of society covered by family Takaful contracts in Malaysia is still very low compared to conventional insurance.Therefore, the study aims to propose a conceptual framework for the determinants of family Takaful demand in Malaysia. From a review of the literature available in this particular area of interest, there are two categories of factors that are found to be the main determinants of family Takaful.These factors are the socio-demography and economic factors

Students’ Reflection towards the Integration of Tawhidic Science in the “Pandang Alam” Camp

The purpose of this study is to observe students’ reflection towards the integration of Tawhidic Science at the program “Kem Pandang Alam”, at Tanjung Tuan Wildlife Reserve and several other locations nearby Tanjung Tuan, Teluk Kemang and Si Rusa, Port Dickson, Negeri Sembilan Malaysia. The respondents of this study were 32 students from tahfiz schools and tahfiz science schools (15 boys and 17 girls). These students were exclusively selected candidates from their respective schools. Data were analysed based on constant comparative analysis. The finding reveals that there were seven themes including greatness of God’s knowledge; nature as the source of knowledge, education and lesson; improvement of faith; self-development, the formation of identity, the increase of awareness, and the closer of social relations. The implication of this study is to expose these students the importance of the integration of Tawhidic Science where science and religion are inseparable from everyday life

Growth response of Heritiera simplicifolia (Mast.) Kosterm. and Scaphium macropodum (Miq.) Beumée ex Heyne due to abiotic factors in the nursery

In the earliest stage of development, non-dipterocarp wildlings require specific environmental conditions; they are only able to acclimate to harsher environmental conditions after this stage. As such, the environment acts as a limiting factor of early-stage development in non-dipterocarp shade-tolerant species. We examined the survival rates and growth rates of Heritiera simplicifolia and Scaphium macropodum from the family Malvaceae in the different sets of abiotic conditions. Three abiotic environmental factors medium type, greenhouse technique, and light intensity were varied. The experiment was conducted for six months in an area near Hulu Terengganu Hydroelectric Dam, at the edge of the Tembat Forest Reserve. Height, diameter, leaves numbers, and leaf area was recorded. Our results indicate that the wildlings preferred higher daytime relative humidity and natural air ventilation at night, and they grew more quickly under SN50 (358.74 Photosynthetically Active Radiation; PAR) than under SN70 (101.41 PAR). Subsoil supplemented with vermicompost improved wildling growth more consistently than subsoil supplemented with compost or burned mesocarp. The wildling’s height relative growth rate (HRGR) and survival were affected by all treatments. These results indicate that restoration efforts using young indigenous tree species at degraded sites, supply better growth environments and organic nutrients to the rhizosphere

Growth response of Heritiera simplicifolia (Mast.) kosterm. and Scaphium macropodum (Miq.) Beumée ex Heyne due to abiotic factors in the nursery

In the earliest stage of development, non-dipterocarp wildlings require specific environmental conditions; they are only able to acclimate to harsher environmental conditions after this stage. As such, the environment acts as a limiting factor of early-stage development in non-dipterocarp shade-tolerant species. We examined the survival rates and growth rates of Heritiera simplicifolia and Scaphium macropodum from the family Malvaceae in the different sets of abiotic conditions. Three abiotic environmental factors medium type, greenhouse technique, and light intensity were varied. The experiment was conducted for six months in an area near Hulu Terengganu Hydroelectric Dam, at the edge of the Tembat Forest Reserve. Height, diameter, leaves numbers, and leaf area was recorded. Our results indicate that the wildlings preferred higher daytime relative humidity and natural air ventilation at night, and they grew more quickly under SN50 (358.74 Photosynthetically Active Radiation; PAR) than under SN70 (101.41 PAR). Subsoil supplemented with vermicompost improved wildling growth more consistently than subsoil supplemented with compost or burned mesocarp. The wildling’s height relative growth rate (HRGR) and survival were affected by all treatments. These results indicate that restoration efforts using young indigenous tree species at degraded sites, supply better growth environments and organic nutrients to the rhizosphere