PGJ 2010

The following are the abstract of the articles included in this issue of the Philippine Geographic Journal:

————- —Ψ ————-


 Rodelio Carating, Juliet Manguerra and Irvin Samalaca

             The extent of Mt. Pinatubo eruptions through the 1990 (pre-eruption), 1992, 1993, and 2006 satellite imageries are compared to assess soil formation and development for the rehabilitation of the lahar-affected areas in relation to agricultural development. Catastrophes such as volcanic eruptions mark Time Zero in soil formation and development.  Although initially destructive, and the volcanic deposits are sterile and hot, volcanic ash deposition on a landscape refreshes the soil, improves the physical and chemical properties, and renews soil productivity.  Volcanic ash soils are important components of soil organic matter that are main sources of nitrogen for plants and various nutrients and energy for soil organisms, as well as important contributors to carbon sequestration and global stability from climate change. Mt. Pinatubo ash contains 1.7 g P2O5 kg-1, mostly occurring as apatite that enhances the plant-available phosphorus.  It should be noted, however, that the pre-1991 eruption study shows that the soil development pathway is characterized by dominance of allophane, hence, we should expect high phosphate retention and non-availability to plants despite its abundance. The time series study on the development of Pinatubo volcanic-influenced ash-soils shows that the weathering process proceeds rapidly for many of the affected areas.   The time series satellite imageries provide an interesting study on soil development of Mt. Pinatubo volcanic ash soils, i.e., the old lahar deposits are just overlain by the new and quite large areas of lahar deposits and no longer appear as lahar in the satellite images.  The characteristics of these volcanic ash soils for agricultural use and the appropriate soil management recommendations are provided.

 ————- —Ψ ————-


Ian Douglas

  The tropical climates and varied rocks and landforms of S.E. Asia have posed challenges for successful design, safety and hazard management in rapidly growing cities.  Good urban planning requires a sound understanding of the ground on which cities are built.  Without knowledge of the subsurface karst features of Kuala Lumpur or the complex Quaternary deltaic deposits of Bangkok, the modern skyscrapers of those cities could not be built.  Many cities in Indonesia and the Philippines require detailed understanding of the history of nearby volcanoes as well as knowledge of the risks associated with both potential eruptions and the instability of slope deposits from previous eruptions.  Almost everywhere in hilly terrain, urban construction can potentially trigger landslides, but the potential for such mass movements all too often goes unrecognized.  Removal of the original forest vegetation and exposure of bare soil or weathered rock leads to erosion and sediment production.  The sediment is washed into rivers and aggravates flood problems as well as often causes damage to water supply intakes, while its deposition can disrupt both urban and rural activities.  However, urban development also creates landforms, whether they are the result of deliberate encroachment by filling on to floodplains or shorelines, or just the accumulation of material on the surface by the dumping of construction debris, domestic waste and landfill operations.  All such changes to landforms have to be made with an understanding of the geomorphic processes that will affect them.  Such an understanding should be part of the general education of all professionals involved in urban design, planning, infrastructure management, real estate operations and housing provision.

 ————- —Ψ ————-


Pepito R. Fernandez, Jr.

 The Philippine archipelago is an important center of tropical coastal marine biodiversity.  Fisheries and coastal resources are also important sources of livelihood to subsistence and commercial fishers. Since the 1970s, various national and international actors have popularized marine protected areas (MPAs) as an effective tool and governance framework for coastal conservation, tourism, and even social empowerment.  Scholars and practitioners, however, are often guided by bureaucratic and bio-centric perspectives that overlook the different actors and complex institutions that frame and contest MPA design, implementation, and outcomes.  Pursuing apolitical perspectives and marginalizing subsistence fishers in MPA governance and management, in turn, lead to project and program failures that fuel low morale among key stakeholders, continued environmental destruction, and impoverished coastal communities. This paper describes the resources and power relationships of key actors in MPA decision-making in four sites in Northeastern Iloilo Province, Philippines. The paper explains that state-led, community-based and co-managed MPAs in the case study sites are socially constructed and contested.  In such MPA spaces, actors have complex negotiations that have diverse and uncertain socio-political and ecological results.  It is argued, however, that unless state and non-state actors link improved coastal ecosystem management, effective MPA governance, and opportunities to enhance local livelihoods, then existing institutional arrangements will unlikely promote social justice and equity, and productive ecosystems.

 ————- —Ψ ————-


Mahesh Rao

 The Conservation Reserve Program is the largest of the USDA conservation programs with 36.8 million acres enrolled and $1.8 billion in payments distributed to U.S farmers and ranchers for FY 2008. In Oklahoma, nearly 1.1 million acres are currently enrolled in the CRP with an annual distribution to landowners amounting to approximately $35.3 million. The CRP was established in the Food Security Act of 1985 to remove highly erodible land from crop production and establish a protective vegetative cover. The CRP is a voluntary program using financial incentives to encourage farmers to enroll in 10-15 year contracts. Landowners receive annual rental payments and cost-share assistance to establish an approved vegetative cover. The environmental benefits of CRP were characterized using the GIS-based Soil and Water Analysis Tool (SWAT) for Texas County, located in the Oklahoma Panhandle. Spatial analysis involved overlays of simulated sediment yield and CRP areas in the county. Sediment yield ranged between 0.02 to 0.3 tons/acre/year (0.04 and 0.70 tons/ha./year). The highest sediment yield was observed in the southeastern corner of the county while the lowest sediment yield was observed in the northwestern corner and south of the county. Reductions in sub-basin sediment yield for the pre- and post-CRP scenarios ranged between zero and 68%, with an average reduction of 32.6% for the county. A questionnaire-based study was conducted to identify the societal attitudes and perceptions that influence the CRP participants in the Panhandle region of Oklahoma. An informative research analysis methodology was adopted to identify some of the decisions and preference of participants towards environmental quality as a result of participating in the CRP. A majority of CRP participants (61.2%) agreed that the U.S. government is paying adequate attention in controlling soil erosion. Results indicate that the participants agree that there is adequate attention paid by the government on water and air quality improvement. However, the study revealed that the government is not paying adequate attention to water and air quality improvements. Overall, the perceptions of the CRP participants in the Oklahoma Panhandle favor the continuation of the Conservation Reserve Program in the region. However, re-enrollment preferences in their participation could be improved with certain modifications in the Environmental Benefits Index.

 ————- —Ψ ————-


 Raman Mariyappan and Khairulmaini Osman Salleh

            Developing the environmental resources in Penang Island offers a great future to the island itself and, of course, to Malaysia in general. In doing so, in the past 10 years the island faced tremendous pressure especially when new problems related to the environment crop up. The paper will be discussing the issues, policies and challenges related to environmental resource and development. In doing this, it is important to realize that the biological and other resource base of the island is not a fixed entity. It is dependent in part on human activity and in part on the changing nature of the biosphere. In Penang Island, human activity – especially land use change – has played a very important role in changing the environment. Human demands on natural resources are increasing, to the extent that new approaches to their planning and management are needed. The island, as one of the fastest growing states in Malaysia, faces new challenges in developing its environmental resources. Land is considered as the most important resource being developed to accommodate the ever-growing industrial and commerce sector. The influence of land use changes on environmental catastrophes, and also the sudden shifts in land use pattern due to economic development, can contribute towards environmental degradation. Changes in land usage and land use pattern constitute the most influential factor in the occurrence of environmental disasters. The current threat to the environment, which is a common concern of all mankind, stems essentially from past neglect in managing the natural environment and its resources. The drastic change that occurred can be traced to man’s capacity to develop technology. This can occur directly through activities such as habitat loss and urban expansion. Penang has experienced a unique situation wherein the significant economic development was achieved without sacrificing most of the natural environment. However, the recent shift in activities in the economic sector has created a new fear i.e., the present balance between economic development and natural environment may not be sustained. If current development trends continue, the present balance between economic development and natural environmental sustainability may not be maintained in the longer term. The government’s prime concern is to formulate appropriate environment policies for the protection and preservation of existing desirable environmental conditions in the island.

 ————- —Ψ ————-


Seif Abdullah and Marani Maryam

Sagzee Desert as a survivor of the great Gavkhooni playa, situated 25 kilometers from the east of Isfahan, is considered as one of the critical desertification centers and a gateway for the entrance of the desert realm into the historical city of Isfahan. Therefore, the control of this desert is indispensable due to its specific location in relation to Isfahan. This research deals with the investigation of the desertification trend of the Sagzee Desert realm through the use of Landsat satellites images within two time limits (within a period of 30 years).The satellite images studied in the present research were adapted from ETM+ and MSS sensors of the first and the seventh generation of Landsat designed in 1972 and 2001. After geometric corrections and image processing, multiple false color mixes were prepared which enjoyed the best color contrasts by different representation operations. Then from the intended realm, seven sites with equal distribution in the old and new images were chosen and the changes were presented by comparison and eye interpretation at two time limits.  With reference to the comparison of the related images and the obtained results, it should be admitted that the density of plant cover in far-off places around the desert, especially around its southern and eastern regions, shows an increasing trend. This is the result of the changes in the use of land and the implementation of plans to combat against desertification for the purpose of safeguarding residential places, factories and airport territories against negative consequences of desertification and other desert damages. In some places, especially the center of the desert , the desertification trend and the appearance of sandy and chalky facies show an  increasing trend in the new images

 ————- —Ψ ————-

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s