Targeted cattle grazing as an alternative to herbicides for controlling weeds in bird-friendly oil palm plantations

The use of agrochemicals is expected to increase with the global expansion of oil palm plantations. In line with environmentally sustainable palm oil certification, targeted grazing can minimize the dependency on herbicides for controlling weeds in plantations. Here, we show for the first time that targeted grazing would control weeds and improve biodiversity of desired animal species. We sampled birds at 45 oil palm plantations in Peninsular Malaysia that were systematically grazed, non-systematically grazed, or herbicide-controlled plantations without cattle grazing. We found that bird species richness increased with size of grazing area, but decreased with number of cattle. Bird abundance was higher in the systematic grazing system, but negatively related to number of cattle. These factors explained 18.41 and 25.34% of the observed variations in bird species richness and abundance, respectively. Our findings suggest that targeted cattle grazing can be instrumental for transforming conventional oil palm agriculture into more biodiversity-friendly agroecosystems. Targeted grazing is likely to be practical under field conditions in major palm oil producing countries. In addition, the use of targeted grazing as a biological control method for weeds would be welcomed by palm oil consumers and encouraged by sustainable palm oil certification bodies such as the Roundtable on Sustainable Palm Oil (RSPO)

Alley-cropping system increases vegetation heterogeneity and moderates extreme microclimates in oil palm plantations

Forest conversion to oil palm plantation is causing a major loss of biodiversity in Southeast Asia and other tropical regions. Oil palm plantations have less biodiversity because of their simplified vegetation, human disturbances, and extreme microclimate conditions. Alley-cropping system incorporates a secondary crop in the alleys between the main crops. In some cases alley-cropping can result in a greater vegetation structural complexity, thus potentially providing agricultural and ecological benefits, including: buffering against weather extremes, reduction in soil erosion, increased biodiversity, and increased nutrient and water-use efficiency. In this study, we compared vegetation structure (height and cover of vegetation), microclimate (air temperature, relative humidity, light intensity and wind speed), and soil conditions (soil surface temperature, soil pH and soil moisture) across a range of alley-cropping systems and two ages of monoculture oil palm. We found that alley- cropping system had varied structural complexity across different crops when compared to oil palm monoculture system. Careful selection of crops was essential, with black pepper and cacao having the largest impact on improving vegetation heterogeneity and microclimate regulation when incorporated into an alley-cropping system. In particular, we found that systems intercropped with black pepper had air and soil surface temperatures up to 1.3 °C and 2.1 °C cooler than those in oil palm monoculture. In contrast, systems intercropped with bactris and bamboo had increased air temperatures. Our findings show that some alley-cropping systems have great potential as a climate-smart practice in sustainable oil palm agriculture. This study also shows that careful selection of crops is important in the planning and management of future alley-cropping system to optimise the ecosystem benefits that can be gained from this management system

Performance Of CVD Coated Carbide Tool By Optimizing Machining Parameters During Turning Titanium Alloy Ti-6AL-4V ELI In Flooded Condition

In metal cutting, one of the important elements which must seriously consider is cutting tools. Carbide cutting tool is widely used in machining process for various metal types. This paper presents the performance of cutting tools in turning Ti-6AL-4V ELI using the CVD coated carbide tool under flooded conditions. Experimental design of this study is based on Factorial method. Two Level Factorial designs were selected to arrange the cutting parameters of cutting speed with a range of 100 to 140m/min, feed rate with 0.15 to 0.20mm/rev, and depth of cut was kept constant at 0.35mm. Flank wear was measured using a three axis microscope. The values were recorded for each length of the workpiece until flank wear (Vbavg) average reaches the tool life criterion, Vbavg = 0.3mm followed by International Standard ISO 3685. From the result obtained, it is found that lowest cutting speed and feed rate resulted in longer tool life while highest cutting speed and feed rate resulted in a much shorter tool life. Based on the ANOVA analysis, cutting speed is the most significant factor followed by feed rate. Mathematical modelling was developed and the error between experimental results and generated model is 19%. The optimum responses are obtained at cutting speed 100m/min, feed rate 0.15mm/rev, and this give out the longest tool life of 15.43minutes while shortest tool life, 4.07 minutes was obtained at cutting speed of 140m/min and feed rate 0.20 mm/rev. The error value of optimization between experimental and model is 0.19%. From this research, even though titanium alloy, Ti-6Al-4V is considered as material with low machinability, there are suitable cutting parameters available to give out the longest tool life thus reducing machining cost

Alley-cropping system can boost arthropod biodiversity and ecosystem functions in oil palm plantations

Oil palm (Elaeis guineensis) is among the fastest expanding crops, due to high global demand for vegetable oils. Large areas of forest are converted into oil palm plantation to meet the market demand in producing countries which causes rapid decline in tropical biodiversity, including arthropods. The alley-cropping system has the potential to promote faunal biodiversity, related ecosystem services and food security in agricultural landscapes. In alley-cropping, a main crop is intercropped with a secondary crop (often a food crop), secondary crops are cultivated in the alleys in between the main crop. We compared arthropod taxonomic richness, arthropod predators and decomposers between five alley-cropping treatments (pineapple, bamboo, black pepper, cacao, bactris), where oil palm is intercropped with another species. In addition, we sampled two control treatments: monoculture oil palm, aged seven and 15 years old. A total of 50,155 arthropod individuals were recorded using pitfall trap sampling, representing 19 orders and 28 families. Fourteen orders belonging to sub-phylum Insecta, three orders from Arachnida (Araneae; Acarinae; Scorpiones) and two orders from Myriapoda (Chordeumatida; Geophilomorpha). We detected an increase in beta-diversity of oil palm production landscape. Specifically, we found that the number of arthropod orders, families and abundance were significantly greater in alley-cropping farming plots than those in monoculture plots. In addition, alley-cropping treatments contained larger numbers of predators and decomposers. Our findings suggest that the alley-cropping system can become a key management strategy to improve biodiversity and ecosystem functions within oil palm production landscapes

Making Friends in the Rainforest: Negrito Adaptation to Risk and Uncertainty

The so-called negritos adapt not just to a tropical forest environment but also to an environment characterized by perturbations and fluctuations. As with other hunter-gatherers in the region and, indeed, throughout the world, they use both social and ecological methods to enhance their chances of survival in this changing environment: socially, they have developed networks of trading and marriage partners; ecologically, they maintain patches of key resources that are available for future harvesting. As evidenced in the case of the Batek (Orang Asli), patterns of forest structure and composition are sometimes direct outcomes of intentional resource concentration and enrichment strategies. While little of the above is controversial anthropologically, what has drawn some debate is the nature of the relationship with partner societies. Conventional wisdom posits relations of inequality between foragers and others : foragers and farmers are often construed as hierarchical dyads where foragers supply products or labor to farmers in exchange for agricultural harvests and other trade goods. This kind of adaptation appears to be one of divergent specialization. However, there are cases, such as in the relationship between Batek and Semaq Beri, where both societies follow a roughly similar mode of adaptation, and specialization has not materialized. In sum, while not denying that hierarchy and inequality exist, I suggest that they have to be contextualized within a larger strand of relationships that includes both hierarchy and egality. Further, such relationships are part of the general portfolio of risk reduction strategies, following which access to widely scattered environmental resources, and passage from one location to another, is enhanced not by competing with and displacing neighbors but by maintaining a flexible regime of friendly exchange partners

Modelling of leaching process of rare earth element Praseodymium (Pr)

Rare earth elements have their unique physical and chemical properties character that makes them important elements in several of high-tech application. It’s very important to ensure the efficient separation of REE is carried out optimally. In order to achieve this, understanding the fundamental process is essential. Thus the purpose of this study is to relate how the leaching process occurs by using shrinking core model for a better understanding. Rare earth separation process usually passed through a cascade of physical processing steps including beneficiation process. After filtration, leaching solution is passed through a sequence of solvent extraction process with several mixer-settler steps to separate individual or mixed rare earths compounds. The aims of this work are to study and develop a model for leaching process of rare earth elements, Praseodymium (Pr). It was conducted for the purpose of the recovery of the rare earth element from ore. The mathematical model of this work was developed based on the shrinking core model (SCM). The effect of temperature ranging from 30oC – 80oC and concentration (1.5 mol/L – 3 mol/L) of the reagent was carried out in this work. The developed model from this work can be used to predict the recovery of Praseodymium (Pr) from the solid liquid leaching process which can be a good reference for future research

Removal of Cadmium using Alkaline-Treated Activated Carbon from Leucaena Leucocephala Biomass

Water contamination that caused by heavy metals is a very common phenomenon in the industrial age. One of the popular way to treat metal contaminated water is by adsorption process using activated carbon as the adsorbent. This paper works on producing activated carbon by chemical means with impregnation ratios of NaOH:char (w/w) was predetermined at 1:1 (ACT1-1), 2:1 (ACT2-1) and 3:1 (ACT3-1) under activation temperature of 700°C. Considering the Leucaena leucocephala is a wildly, easy and fast grown species, with the availability throught the year, it was chosen to be used as the precursor. The properties of these activated carbons and its potential for cadmium removal from aqueus solution was analyzed. It was found that the highest surface area was recorded at 662.76 m²/g. Four parameters were studied which are contact time, the effect of pH, initial concentration of adsorbate and temperature. The equilibrium time was achieved in 40 min treatment at initial concentrations of 30 mg/l. The adsorbent exhibited good sorption potential for cadmium at pH 8.0 and equilibrium temperature of 30℃. Based on the results, this study had proved that activated carbon from Leucaena leucocephala biomass have the good potential to be used for removal of cadmium from wastewater

The upper respiratory tract microbiome of indigenous Orang Asli in north-eastern Peninsular Malaysia

Abstract Much microbiome research has focused on populations that are predominantly of European descent, and from narrow demographics that do not capture the socio-economic and lifestyle differences which impact human health. Here we examined the airway microbiomes of the Orang Asli, the indigenous peoples of Malaysia. A total of 130 participants were recruited from two sites in the north-eastern state of Terengganu in Peninsular Malaysia. Using 16S rRNA sequencing, the nasal microbiome was significantly more diverse in those aged 5–17 years compared to 50+ years (p = 0.023) and clustered by age (PERMANOVA analysis of the Bray–Curtis distance, p = 0.001). Hierarchical clustering of Bray–Curtis dissimilarity scores revealed six microbiome clusters. The largest cluster (n = 28; 35.4%) had a marked abundance of Corynebacterium. In the oral microbiomes Streptococcus, Neisseria and Haemophilus were dominant. Using conventional microbiology, high levels of Staphylococcus aureus carriage were observed, particularly in the 18–65 age group (n = 17/36; 47.2% 95% CI: 30.9–63.5). The highest carriage of pneumococci was in the <5 and 5 to 17 year olds, with 57.1% (4/7) and 49.2% (30/61), respectively. Sixteen pneumococcal serotypes were identified, the most common being the nonvaccine-type 23A (14.6%) and the vaccine-type 6B (9.8%). The prevalence of pneumococcal serotypes covered by pneumococcal conjugate vaccines support introduction into a Malaysian national immunisation schedule. In addition, the dominance of Corynebacterium in the airway microbiomes is intriguing given their role as a potentially protective commensal with respect to acute infection and respiratory health