mortiz085

By Dr. Luz Geneston Asio Department of Agronomy, Visayas State University The highlands in the middle of Cebu which extends from the city in the east to Balamban/Asturias in the west, presents a beautiful mixture of protected landscapes with good secondary forest cover, and crop production systems consisting of orchard particularly mango, annual crops, vegetables and cut flowers.  Beautiful views of the Cebu Highlands The very beautiful scenery reminds visitors of Baguio City or some foreign places like Indonesia or Taiwan. Clearly observable even on distant undulating slopes are the mango trees which are adapted to the agroclimatic conditions of Cebu.  Mango trees are abundant in certain parts of the landscape Cebuanos are widely known to be corn eaters. This explains why corn is the most widely grown grain crop in the highlands. On red acidic soils from igneous rocks as well as on dark calcareous soils from limestone, nutrient deficiency symptoms (N, P) are clearly observabl...

by Johannes R. G. Asio Institute of Tropical Ecology and Environmental Management (ITEEM),VSU, Baybay City, Leyte, Philippines Introduction Dipterocarp trees ( Dipterocarpaceae ) have crucial ecological roles such as in the prevention of landslides, sequestration of atmospheric carbon, and biodiversity. They are also economically important in terms of timber production. These native trees are also adapted to a variety of climatic conditions and geographic locations (e.g. areas prone to heavy typhoons, marginal lands). However, the sustainable management of dipterocarp forests is still poorly understood due to the limited studies conducted on the subjet. This is particularly so in terms of the ability of these forest trees to thrive in marginal lands like those naturally contaminated with heavy metals and those soils with very low nutrient status such as ophiolitic and serpentinite areas (Corlett&Primack, 2006; DENR, 2012; Appanah, 1998; Walpole, 2010). Ophiolite rocks are widespre...

The gently rolling topography which typifies a large portion of the volcanic landscape in Claveria makes it ideal for intensive large-scale vegetable production. The widely grown vegetables include cabbage, beans, tomato, sweet pepper and eggplant. The breathtaking volcanic landscape of Claveria, Misamis Oriental But the strongly weathered soils which range from Oxisols in the lower slopes (about 400 to 600 m above sea level or asl) to Ultisols in the upper slopes (about 600 to 900m asl) are a major constraint to vegetable production in the area. Oxisols (also called Ferralsols) and Ultisols (also called Alisols and Acrisols) are clayey, reddish, acidic and nutrient-poor soils although they generally have good physical properties like good structure and moderate to high porosity. As in other volcanic landscapes, the oldest and most infertile soils (Oxisols) are formed on the older and stable lower slopes. Dr. Apol & Nelds Gonzaga, Ruby Gabaca, Dr. Steve Harper & myself in fro...

Weathering is the alteration by chemical, mechanical, and biological processes of rocks and minerals at or near the Earth’s surface, in response to environmental conditions. Highly weathered soils (or strongly weathered soils) are soils that have undergone prolonged and intense weathering under the net leaching environment of the humid tropics. They are commonly found on stable and old geomorphic surfaces underlain by easily weatherable rocks such as ultrabasic and basic rocks as well as by pre-weathered sediments (Beinroth, 1982). These soils are clayey, deep, reddish, acidic, and have low nutrient status. According to Jackson et al. (1948), highly weathered soils are characterized by weathering stages of 10 to 12 wherein the clay fraction is dominated by 1:1 phyllosilicates (kaolinite & halloysite), aluminum oxide (gibbsite), and iron oxides (goethite and hematite). This mineralogical characteristic is also predicted by the “residua hypothesis” of Chesworth (1973) which states th...

The Visayas State University (VSU), through the Philippine Higher Education Research Network (PHERNet) of the Commission on Higher Education (CHED), is spearheading a research project on enhancing farm productivity and environmental quality in climate change vulnerable marginal uplands in Eastern Visayas. As part of the project activities, the university will organize a National Conference on Development Initiatives in the Philippine Philippine Marginal Uplands, with the theme, "Enhancing farm productivity and environmental quality of Philippine marginal uplands: A scan of the past and a look into the future." The conference will be held on 22-24 October 2013 at VSU, Baybay City, Leyte.

Marginal uplands are hilly or mountainous lands having very low crop productivity due to poor soil quality (degraded soil), limited water availability, and unfavorable socio-economic conditions. They are widespread in Southeast Asia and other parts of the humid tropics (e.g., Agustin and Garrity 1995; Asio et al., 2009). Resource poor-farmers (~ 1.4 billion people) in the developing world are located on these risk-prone marginal environments (Altieri 2002).  Marginal uplands in Inopacan and Hindang, Leyte In the Philippines, the poorest households, who are also the most vulnerable and most food insecure, are living and farming on these marginal lands (Roa 2007). The agro-ecological conditions in these areas are typically not suited to intensive production systems due to low-quality soils, hilly slopes, limited access to inputs or markets and extremely diverse and site specific conditions (Asio et al., 2009; Tyler 2004). Crops that can be grown on these marginal lands are often rest...