Journal of Developments in Sustainable Agriculture
Online ISSN : 1880-3024
Print ISSN : 1880-3016
Volume 8 , Issue 1
Showing 1-7 articles out of 7 articles from the selected issue
Journal of Developments in Sustainable Agriculture
  • Junko Shindo
    2013 Volume 8 Issue 1 Pages 1-12
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
      Based on the changes in food demand and production in East Asian counties, the temporal trends from 1980 to 2007 and spatial variation of nitrogen outflow via three channels (nitrogen balance (NB) in agricultural areas, human waste and atmospheric deposition) were estimated with a simple nitrogen flow model. In many countries, food consumption has rapidly increased due to population growth and increase in per capita food demand, especially demand for animal protein. In contrast, per capita food demand in India was almost stable despite economic growth. Reflecting these food demands, consumption of inorganic nitrogen fertilizer and resulting nitrogen balance (NB) per unit agricultural land have increased drastically in many countries. In some countries such as Cambodia, Laos and Myanmar, NB was very low or negative even in 2007 suggesting that soil fertility may become exhausted. NB varies significantly within countries and it was extremely high in cities and provinces in China facing the East China Sea and the western Plain of Hindustan in India.
      Total nitrogen outflow from river basins, which is the sum of the outflows from the three channels in each 0.5 °×0.5° grid cell in the basins, also showed large variability. The Yangtze River basin accounted for the largest share of the total nitrogen outflow, about 20% of the total load of the study area. Comparing the average nitrogen outflow per unit land area in 2007, the Huai River basin had the largest value by a wide margin and may be severely polluted with nitrogen.
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  • Taichi Maki, Osamu Morita, Yoshinori Suzuki, Kenji Wakimizu
    2013 Volume 8 Issue 1 Pages 13-24
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
      Cloud seeding experiments using liquid carbon dioxide were carried out on 26 and 27 February 2012 near Miyake Island in the Izu Islands south of Tokyo, Japan. Convective clouds developed 0.5 to 1 h after the seeding near Miyake and Mikura Islands and reached heights of 3000 m and 4000 m on 26 and 27 February, respectively. Artificial convective clouds accompanied by rain, i.e., virga were observed, and rain was recognized by eye around Miyake and Mikura Islands on 27 February; we presume that the amount of rain increased on the mountainous part of the island. Consistent with cloud trajectories estimated from weather data, the artificial cloud was recognized as radar echoes later on 27 February east of Mikura Island as a chain of clouds at 3000 to 5000 m elevation. We found that seeding with liquid carbon dioxide within convective clouds near their bases is feasible when the air temperature is below -5°C. The practicality of liquid carbon dioxide seeding is supported by the results of this study, and we believe the spread of the technique.
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  • Koshi Yoshida, Issaku Azechi, Ryunosuke Hariya, Kenji Tanaka, Keigo No ...
    2013 Volume 8 Issue 1 Pages 25-31
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
    In the Asian monsoon region, which has distinct rainy and dry seasons, the water cycle will be accelerated by global warming, leading to more intense rainfall and long-term drought. The growing population in Indonesia will require increased food production in the future, and the floods and droughts induced by global climate change will affect agricultural production directly and indirectly through soil erosion and/or changes in carbon and nutrient dynamics in soil. Therefore, evaluation of spatial and temporal distributions of available water is necessary to manage water resources effectively. In this study, we predicted the future water availability in the Citarum River basin of West Java. A distributed water cycling model was developed and applied to analyze the water balance in the basin, and a dam operation model was combined with this model to calculate water storage in the reservoirs. According to our analyses, rainfall intensity is expected to lessen in 2046-2055, with rain falling more equally throughout the year and with mid-range amounts of rainfall continuing for longer periods as compared to 1996-2005. The drought period in 1996-2005 was 632 days over 10 years, but in 2046-2055 it is predicted to increase to 881 days. The predicted frequency of flooding increased from two times in 1996-2005 to five times in 2046-2055. These results show that water will become difficult to obtain in the future, and water scarcity and competition among water users will become severe. Our analyses of two irrigation districts showed that the one with water regulation facilities is expected to have more stable water availability in the face of climate change conditions than the one with no such facilities. Thus, it is necessary to construct more water regulation facilities to improve the resilience of the Citarum watershed to water scarcity.
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  • Naoya Fukuda
    2013 Volume 8 Issue 1 Pages 32-40
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
    Plants use light as both a primary energy source and a signal for morphogenesis. Plant growth and morphogenesis are strongly affected by light intensity, photoperiod, and quality. Light quality studies have shown, for example, that plants receiving low levels of red light, in shaded locations (e.g., under dense plant canopies), exhibit rapid stem elongation and flowering. Photoreceptors-complexes of proteins and pigments in plant cells-act as “antennae” to absorb particular light spectra and generate signals to change gene expression through signal transduction systems in plant cells. By modifying gene expression, light signals control not only plant growth, but also flowering time, fruit color, or the functional chemical content of crops. Artificial light sources have now achieved long life, good energy efficiency, and increased luminance. Today, we can use various types of artificial lamps (e.g., fluorescent, metal halide, or hig-pressure sodium) to suit the lighting aims in horticultural crop production, but light-emitting diodes (LEDs) are now the most advanced artificial light sources available. Their energy efficiency is projected to overcome that of fluorescent lamps within 5 years. In addition, because LEDs can radiate narrow spectra, specific lights can be used to control specific plant growth responses, such as plant shape or flowering time, without the need for chemical growth regulators. We can also use new photo-selective filters to modify sunlight and thus control plant growth and insect and disease activity. These new light technologies are still expensive, but expected cost reductions will make the technologies available for protected horticultural production.
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  • Savitree Rangsipaht, Nanthakar Saengchan, Kritsana Parnuwad
    2013 Volume 8 Issue 1 Pages 41-48
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
    The objectives of this research were to answer three main research questions regarding agricultural extension work in Thailand. First, how do we advocate that extension workers work in harmony with agriculturists? Second, what are the advantages of doing so? Third, how can government policies toward extension work be improved? Research methods included the collection of information by using documentary studies and in-depth interviews with Prof. Rapee Sagarik, an innovative thinker who was the recipient of “The Scholar in Agriculture of Thailand” award in 2010 from the Ministry of Agriculture and Cooperatives. The interviews were transcribed and rewritten and then approved by Prof. Sagarik. According to Prof. Sagarik, in order for harmonious and innovative extension work between extension workers and agriculturists, extension workers must work continually with agriculturists in the field; understand the definition and principles of agricultural extension; realize their roles in the current situation; know themselves; be humble; be firm; have faith in their work; be accountable; provide facts to agriculturists; have endurance and be honest, indifferent, generous, and forgiving; be able to work with people from diverse backgrounds; have compassion; and be optimistic. The advantages of harmonious interactions between extension workers and agriculturists are (1) it builds strong linkages between the two groups, and (2) it enables agriculturists to be self-reliant. Based on Prof. Sagarik’s viewpoints, we suggest that a government policy for extension work should be to encourage senior administrators to visit farms to see for themselves how to best serve the needs of agriculturists and best integrate the extension work load among various departments.
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  • Rex Victor O. Cruz, Rosario B. Bantayan, Leila D. Landicho, Nathaniel ...
    2013 Volume 8 Issue 1 Pages 49-62
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
      More than ever before the reformulation of agriculture and forestry education in the Philippines has become increasingly essential in the light of a rapidly diminishing industry sector, shifting uses of land and other natural resources and the changing climate and the environment in general. As its foundational context changes the educational system and programs on agriculture and forestry must also change to be able to produce trained human resources with the skills and orientation consistent with what is required to address the prevailing and emerging problems and opportunities associated with the changing biophysical and socioeconomic landscape. The slow pace of adaptation of agriculture and forestry education has caused the decline of interests among prospective students as the demand for graduates of the traditional programs declines in favor of the rising demand for graduates with new sets of skills. Further, the diminishing opportunities to get employment and start new agriculture and forestry enterprises also erode the attractiveness of professional and business career in agriculture and forestry.
      Needless to say agriculture and forestry education remain vital considering the unabated population growth and increase in the demand for food, fiber, wood and other related goods. But to remain responsive and relevant, agriculture and forestry education must rise up to the challenge of transforming it into a system where the end products are graduates with the desired set of skills and knowledge that are necessary to make a positive difference in the industry sector and the overall improvement of the state of the biophysical and socioeconomic environment.
      Toward this end the Philippines through the Commission on Higher Education (CHED) aims to redesign the highly performance based educational system for agriculture and forestry into a largely outcomes based system. This paper presents the key elements of the envisioned reformulated agriculture and forestry education program along with the concerns, problems, opportunities and constraining and facilitating factors for its full and prompt adoption.
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  • Paul G. Johnson
    2013 Volume 8 Issue 1 Pages 63-71
    Published: 2013
    Released: March 15, 2013
    JOURNALS FREE ACCESS
    Turfgrasses are unique crop plants in how they grow, how they are managed, how they are used, and what people expect from them. Although citizens often are not aware of their role, turfgrasses are very important to the sustainability and quality of life in urban areas throughout the world. While often misunderstood, people come in contact with turfgrasses constantly, providing recreational opportunities and cultural benefits including creating improved physical and mental health. As living plant systems, they protect soils and influence beneficial modifications to urban climates. Although turfgrasses are highly adaptable and do not require levels of inputs many people believe, management of these turfgrass areas, particularly intensively used recreational turf is becoming more demanding with increased use and reduced resources available. In order to meet those needs, extensive knowledge in a number of disciplines is needed as well as communication skills. In addition, education needs to focus on systems, often beyond the locality, and balance economic, social, and environmental necessities. Examples of decision points in achieving this balance are provided. While challenging, addressing sustainability in turfgrass areas will improve the locations and the urban areas themselves. Education of managers to understand this balance is most challenging in areas where local expertise is not available. This review highlights examples of poor transfer of expertise and then provides three mechanisms being used currently to develop local expertise. Collaboration of local expertise with outside experts can benefit both sides.
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