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Response of corn to chicken dung and rice hull ash application and mycorrhizal fungi inoculation

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By Luz Geneston-Asio, Central Analytical Services Lab, VSU, Baybay, Leyte The use of locally available and cheap organic fertilizers like chicken dung and rice hull ash which have the ability to increase crop yield and at the same time improve soil quality is becoming popular among farmers in many places in the Philippines. In addition, considering that the world demand for corn as food and feed is projected to greatly increase in the coming decades, there is a need to explore the use of such materials for corn production. We evaluated the growth and yield responses of corn to chicken dung and rice hull ash application a well as to mycorrhizal fungi inoculation. The experiment was laid out in a split-plot in Randomized Complete Block Design consisting of three replications. Vesicular-arbuscular mycorrhizal (VAM) inoculation served as the main plot while application of fertilizer was designated as the subplot. The fertilizer treatments included the following: To-control, T1-inorganic fe...

Effects of Lantana camara on soil properties and neighboring plants

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Lantana camara Linn, locally called Utot-utot , Koronitas or Kantotoy in the Philippines, is a shrub which originated from tropical America. It is considered as one of the worst invasive plant species and is a noxious weed in many parts of the world. The plant is known to suppress the regeneration of neighboring plants through allelopathic effects (by releasing volatile and non-volatile chemicals from its tissues and residues). The spread of Lantana is aided by the characteristic of its leaves which is somewhat poisonous to animals while its fruit is a delicacy for many birds which distribute the seeds (Wikipedia). In a recent study published in Geoderma journal, Ling Fan and co-workers evaluated the chemical and microbiological properties of the soil underneath the canopy of Lantana camara as well as the soil away from it. They also investigated the effect of Lantana on the growth of three neighboring plant species (ryegrass, mungbean, and radish). Results revealed that the soils ...

Characteristics and formation of rain forest soils from Quaternary basalt in Leyte, Philippines

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The classical view about soils of tropical rain forest ecosystems is that these soils are old, acidic, and infertile. It is now widely acknowledged that this view which has greatly influenced research and management of the fragile rain forest ecosystem during the last several decades is largely a misconception. Although highly weathered soils (Oxisols or Ferralsols) are the most dominant soils in the humid tropics, tropical soils range from relatively young fertile soils (e.g. Inceptisols) to the highly weathered infertile soils (e..g. Oxisols). The extent of highly weathered soils is less in geologically young areas like in much of SE Asia. More detailed investigations of rain forest soils are vital for the sustainable management of this threatened ecosystems. These could also lead to a better understanding of the response of rain forests to climate change. Navarrete et al. (2009) recently conducted a study to evaluate the physical, chemical and mineralogical characterisitics of rain ...

Lead pollution due to vehicular emissions in urban areas in the Philippines

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Lead (Pb) has been known to be toxic since ancient times. It is a widespread contaminant in soils and Pb poisoning is one of the most prevalent public health problems in many parts of the world. It was the first metal to be linked with failures in reproduction. It can cross the placenta easily. It also affects the brain, causing hyperactivity and deficiency in the fine motor functions, thus, it results in damage to the brain. The nervous systems of children are especially sensitive to Pb leading to retardation. Pb is cardiotoxic and contributes to cardiomyopathy (disease of the heart muscle leading to the enlargement of the heart). Pb is released into the environment from the weathering of Pb-containing rocks, the industry, and the combustion of fossil fuels. Emissions from vehicles are thus a major source of environmental contamination by Pb especially in cities. Ona et al. (2006) conducted a study that looked into Pb pollution in selected urban areas in the Philippines with the f...

The causes of the Guinsaugon landslide

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On 17 February 2006, a catastrophic landslide buried the village of Guinsaugon, the second largest village of St. Bernard town (Southern Leyte, Philippines) killing more than a thousand residents and displacing approximately 19,000 people. The landslide originated on an approximately 800 m high escarpment produced by the Philippine Fault that bisects Leyte and the major islands of the Philippines. In a recent article which synthesized the papers presented during an international conference in Leyte 2008 and published in the international journal Bulletin of Engineering Geology and the Environment, Guthrie and co-workers (2009) arrived at the following conclusions: "The approximately 15 million m3 landslide was a result of progressive failures and tectonic weakening in a region made especially vulnerable by the inter-reaction of geological/tectonic, climatic and cultural factors. In southern Leyte, geology and tectonics (including historical seismicity, the progressive disintegr...

The problem of high levels of nickel in soils and plants in the ultramafic area in Samar, Philippines

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Contributed by Janice P. Susaya, Sejong University, Seoul, Korea One of the heavy metals that commonly occur in elevated amounts in natural ecosystems is nickel (Ni). Ni is considered an essential micronutrient for plants, humans, and animals. It can exist in trace amounts in air, food, drinking water, and soils. Although Ni plays an important role in the metabolism of humans and animals, its intake in excesssive amounts or over a prolonged period could pose health ricsks. Studies have shown that children living in polluted areas have hypertrophy of tonsils, enlarged lymphatic nodes, and enlarged livers. There is also evidence that soluble Ni particulate is linked to acute lung injury. High Ni levels in natural ecosystems commonly come from ultramafic rocks (also called ultrabasic rocks). These are intrusive igneous rocks containing less than 45% silica (SiO2) with high concentrations of Ni, Mg, Fe, Cr, and Co. They are found in many places around the world and are common in many place...

A superheavy new element is named "copernicium"

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Source: Website of GSI Helmholtz Center for Heavy Ion Research, Darmstadt Element 112 in the periodic table is named in honor of the great astronomer Nicolaus Copernicus (1473-1543). Copernicus discovered that the Earth orbits the Sun ("heliocentric theory"), thus paving the way for our modern view of the world. The discovering team of scientists at the GSI Helmholtzzentrum für Schwerionenforschung (Center for Heavy Ion Research) in Darmstadt, Germany, led by Professor Sigurd Hofmann (photo) suggested the name „copernicium“ with the element symbol “Cp” for the new element 112. A few weeks ago, the International Union of Pure and Applied Chemistry, IUPAC, officially confirmed the discovery. In around six months, IUPAC will officially endorse the new element's name. This period is set to allow the scientific community to discuss the suggested name "copernicium" before it is finally accepted by IUPAC. Copernicus was born 1473 in Torun and died 1543 in Frombork, P...