AN ECONOMIC EVALUATION OF TWO WATERSHED MANAGEMENT PRACTICES IN TAIWAN1

ABSTRACT: The main purpose of this study is to evaluate the management practice effects on Ming-Hu and Ming-Tan reservoir watersheds during the past 15 years. It is difficult to economically evaluate a watershed project consisting of a number of multisectoral and long term management practices and regulations. However, the reservoirs’ hydropower operations and their associated benefits and costs are highlighted in this study. The estimated management practice value (net present value) of 351 million NT (New Taiwan) dollars and a benefit-cost ratio of 1.189 are obtained for the Ming-Hu subwatershed. Because the Ming-Tan hydropower station only began commercial operation in 1992 the estimated management practice value is negative 103 million NT dollars (net present value) and the benefit-cost ratio is 0.653 in the Ming-Tan subwatershed. If the analysis period is contained to the year 2010, the benefit-cost ratio of Ming-Tan reservoir subwatershed becomes 1.103. Ming-Hu and Ming-Tan subwatersheds together share the benefit-cost ratio of 1.182 and the net present value of 1,589 million NT dollars. The results of the analyses indicate that the Taiwan Power Company, the watershed management agency, has implemented economically efficient watershed practices and regulations in Ming-Hu and Ming-Tan reservoir watersheds and the watershed management practices are worthwhile and should be sustained.     

闽台环保产业合作与发展前景

论述了闽台两地环保产业发展现状，根据福建省环保局“十五”计划目标任务，提出了重点扶持发展的项目与技术。     

台湾:从粤东沿海逆时针旋转而来的陆块

从台湾岛基本地质特征出发,通过与大陆东南沿海及邻近地区之间的地质对比,提出关于台湾岛成因的新假说,即台湾岛是在晚中生代随着东南大陆的离散而逐渐分离出去的一个陆块,并经历逆时针旋转,于中新世以后在福建沿海与大陆碰撞拼贴.     

Landscape structure and bird's diversity in the rural areas of Taiwan

This study tries to discuss the relationship between landscape structure and organisms in the perspective of landscape architecture.The research hypotheses were then proposed as (1) there are relationships between landscape structure indexes and birds‘ diversity in the rural areas of Taiwan;(2)the relationships between landscape structure and birds‘ diversity will be different in different hierarchical levels.In order to increase the bird species,landscape planners could tries to increase the density of water bodies,but decrease the farms and human planted woods.Decrease the density of constructed and human planted grasslands.Increase the area of un-worked acres,natural grasslands,and the area of water bodies and circular the water bodies and natural forest.In order to increase birds‘ diversity,landscape planners could decrease the concentration of paved areas.Concentrate the human planted trees to increase the core areas of woodlands.Increase the area of natural grassland circular.In order to increase the total number of birds in the planning areas,landscape planners could scattered the paved areas and lengthen the constructed areas.Decreases the core region of the constructed areas.Increase the area of un-worked acres and water bodies.Decrease the disturbance of both the interior area of natural and human planted woodlands and try to increase the density of water bodies.The analysis results showed that the small grain size indexes are more suitable for the rural areas of Taiwan to capture the influential factors of bird communities.The high fragmentation of land usages in Taiwan lessens the influences of the regional landscape pattern.     

台湾集集地震近断层强震地面运动加速度时程的随机特性

将强震地面运动加速度时程看作随机过程,选取台湾集集地震的30组近断层加速度时程为样本,研究其相关特性。3方向集系上的自相关矩阵和互相关矩阵表明3方向的加速度时程均为非平稳随机过程,并且相关系数的分布是随机的,这种随机相关性是无法用确定性的数学模型来模拟的。为此,又研究了样本函数的相关特性,即随机过程样本函数的相关函数,结果发现在随机过程的相关函数中包含有明显的随机函数分量,即相关函数仍为一随机过程,我们称这样的随机过程为超随机过程,本文建立了超随机过程相关函数的数学模型。本文的研究表明近断层强地面运动为一复杂的随机过程,对其相关特性的研究应当包括相关系数(性)的大小和相关系数(性)的随机分布两个方面。     

AQUIFER SALINIZATION IN THE YUN‐LIN COASTAL AREA,TAIWAN1

ABSTRACT: This study analyzes possible causes of shallow ground water salinization in the coastal area of Yun‐Lin. The local hydro‐geologic setting is determined from geological drilling data and sea floor topography. Three possible causes (sea water intrusion, salt water percolation through wells, and infiltration of salty water from fish ponds) are evaluated. Chloride concentration is used as an index to measure ground water salinization. Sea water intrusion is modeled by the advective/dispersive equation, and salt water infiltration from wells and fish ponds is calculated by estimating the amount of water percolated. The determined local hydrogeologic setting suggests that the shallow aquifer may be connected to the sea water, resulting in salt water intrusion as a large amount of shallow ground water is withdrawn. The percent contributions of sea water intrusion, percolation through wells, and infiltration of water from fish ponds, to the salinization of the shallow aquifer at Ko‐Hu in the Yun‐Lin coastal area are approximately 27 percent, less than 1 percent and 73 percent, respectively. The results suggest that the vertical infiltration of salt water from fish ponds is the major cause of shallow ground water salinization in the coastal area of Yun‐Lin.     

Background levels of Persistent Organic Pollutants in humans from Taiwan: Perfluorooctane sulfonate and perfluorooctanoic acid

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have recently received attention due to their widespread contamination of the environment. PFOS and PFOA are stable in the environment and resistant to metabolism, hydrolysis, photolysis and biodegradation. PFOS and PFOA have been found in human blood and tissue samples from both occupationally exposed workers and the general worldwide population. This study aimed to determine the background levels of PFOS and PFOA in the Taiwanese population, investigate related factors, and compare exposure in Taiwan to that in other countries. The concentration of PFOS in the 59 serum samples collected from the general population in Taiwan ranged from 3.45 to 25.65 ng mL⁻¹ (median: 8.52), and the concentration of PFOA ranged from 1.55 to 7.69 ng mL⁻¹ (median: 3.22). There was a significant positive correlation (r = 0.51; p < 0.0001) between PFOS and PFOA concentrations. Males had higher concentrations of PFOA and PFOS than females. PFOS levels in serum increased with age. This study is the first investigation to reveal the PFOS and PFOA levels of serum samples in the general population of Taiwan. The levels of PFOS and PFOA in Taiwanese serum samples were comparable with those from other countries (PFOS: 5.0–35 ng mL⁻¹, PFOA: 1.5–10 ng mL⁻¹).     

基于经济联系强度的海峡西岸经济区空间格局分析

海峡西岸经济区的发展经历了提出、发展和形成3个阶段,分析海峡西岸经济区的区位意义,应用引力模型对海峡西岸经济区20个城市间的经济联系量进行计算,并用Mapinfo90专题地图显示海峡西岸经济区空间发展格局。研究结果表明,海峡西岸经济区东部“双核”城市群之间密切的经济联系形成沿海放射长廊,中、西部“次增长点”构成海峡西岸经济区多级体系,沿海发展轴对中、西次增长点具有较强的辐射作用;区域内部的经济联系度由沿海向内陆山区随着距离成本的增加呈现出衰减规律;区域内陆各城市之间的彼此经济联系强度较弱,其中山地地形条件和距离成本是海西城市之间经济联系的主要阻碍因素     

1994年9月16日台湾海峡7.3级地震背景空区对闽粤沿海地震形势的影响

讨论了 1994年 9月 16日台湾海峡南部 7 3级地震对东南沿海地震带地震活动性的影响。从地震学角度出发结合这一地区地震地质背景对这次地震的震前背景空区的客观性进行了分析。并对其震后背景空区演变进行了追踪 ,以期从震后各断裂带受其应力调整的影响中 ,找出应力有可能再次集中的地段 ,这对缩小预测未来可能发生的中强地震的时间、地点、强度范围的预测具有实际意义。     

基于闽台对比的福建耕地变化趋势演绎

闽台因其区域自然背景及历史文化的相似性和经济发展时序递差性成为区域对比研究的理想对象之一。利用闽台相关统计资料对比显示,闽台耕地变化共同呈现出先增后减、时有波动、总体减少的特点,但台湾耕地的先增后减时序后移,并且减少的总趋势较缓。以各市县平均耕地产出计算,福建新增耕地质量低于被占耕地质量,而台湾正好相反。文章最后通过对福建2010年耕地面积的多元回归预测以及闽台耕地对比演绎,说明福建要实现耕地保护目标,除了依靠严格的耕地保护政策外,依靠农业以及非农业的发展,提高现有耕地综合生产力更为重要。