[A-GE28] 地質媒体における流体移動、物質移行及び環境評価

[AGE28-P07] 持続可能性の育成： 有機野菜農場の土壌肥沃度と課題を検証する-フィリピンの事例研究

*甲斐 貴光¹、ツチヤ マリア²、ガルシア ジョセ²、メディナ シンプリシオ² (1.明治大学黒川農場、2.フィリピン大学ロスバニョス校)

キーワード：露地有機野菜、土壌微生物、窒素循環活性評価値、リン循環活性評価値

Organic agriculture is gaining momentum in the Philippines as consumers become increasingly conscious of health and environmental issues. This study investigates soil fertility parameters in organic vegetable farms located in the Sariaya, Quezon and Los Banos, Laguna. Analysis of soil samples collected from four different farms producing outdoor organic vegetables revealed that many soil fertility parameters fall below recommended values for organic production. Macronutrients crucial for plant growth, including nitrogen, phosphate, and potassium, were insufficient, as was the total carbon content indicative of soil organic matter. Additionally, key factors like bacterial biomass responsible for soil organic matter decomposition, as well as nitrogen and phosphorus cycling activities, were found to be inadequate. These collective results indicate that the organic plots lack the necessary fertility to support optimal organic crop growth. The insufficient fertility in these organic plots might be attributed to their recent conversion from conventional cultivation, involving the use of synthetic pesticides and chemical fertilizers, to organic cultivation, approximately seven years ago. This shift potentially negatively impacted soil microorganisms, leading to decreased fertility levels and limited nutrient availability, hindering the ability to sustain organic production. Overall, this case study's findings emphasize the significant soil fertility challenges in these organic vegetable farms, characterized by suboptimal levels of essential macronutrients and lower bacterial biomass and cycling activities. To address these challenges and promote a more sustainable organic agricultural system, farmers and agricultural practitioners must adopt appropriate soil management practices that will enhance soil fertility and support improved microorganism populations, nutrient availability, and overall soil health for successful organic production.