海南岛东南海岸带景观生态规划

对海南岛东南海岸带进行了景观生态规划。根据海南岛东南海岸带的自然资源条件与经济运行特点，将研究区划分为4个生态区：近岸热带海洋旅游区；海水养殖区；海岸平原粮牧生态区；生态林业区。各区的生态与社会经济特征不同，在利用与管理各生态区的过程中应该采取不同的对策措施，即加强宣传教育与宏观管理，以重点项目建设为契机，加快生态经济建设，优化生态经济结构。建立生物多样性管护区。     

Karst groundwater protection in the Kupa River catchment area and sustainable development

One of the most significant water resources in the Republic of Croatia is the catchment area of the Kupa River, located in the region bordering the Republic of Slovenia. About 88% of the total amount of water in this catchment originates in Croatia and just 12% from Slovenia; therefore, the largest part of the catchment area (about 1000 km²) is on the Croatian side of the border. It is a typical karst area of the Dinarides with aquifers characterized by a relatively rapid water exchange, high groundwater flow velocities and aquifers open to human impact from the surface. Consequently, the aquifers are highly vulnerable and at risk. Due to the availability of large quantities of high-quality spring water (about 6 m³/s), the entire area has a strategic importance within the context of any future development strategy pertaining to the western part of Croatia. The catchment area on the Croatian side was investigated using a wide range of research methods that included a classical hydrogeological approach, the detailed hydrologic calculation of water balance to the hydrogeochemical analyses and modelling. The objective was to determine protection zones and protection measures for the whole area. The difficulties are increased due to the fact that the karst catchment area is crossed by major traffic corridors, oil pipelines and a railway and that many settlements and a highly developed wood industry are present. The combination of protecting water resources with adequate prevention measures and necessary remedial activities that should satisfy the very strict requirements necessary for the protection of the karst aquifers while still allowing for present and future human activities is difficult – but not impossible – to achieve. One good example is the present highway with a closed dewatering system and waste water treatment before the water passes into the karst underground system.     

A new approach for the development and management of brackish karst springs

A new approach to the method of artificial upraising of the water outlet point, for management and development of brackish karst springs, uses the MODKARST model. Brackish karst springs simulation can be used to estimate the necessary upraising of the spring elevation, so that sea-water intrusion is blocked. The consequent freshwater loss to the sea, due to this upraising, can also be estimated. The method has been applied to the periodically brackish karst Almiros spring at Heraklion of Crete, Greece. The spring simulation showed that the sea-water intrusion could be prevented through an artificial upraising of the water-outlet point, realized by the construction of a dam. The exact upraising has been estimated. Freshwater loss to the sea because of this upraising has also been estimated. The model could also be used as a tool for the management of the spring. For example, it was used to assess management options for the spring during the depletion period of the year 1994. The best scenario for the development of the spring during this period has been estimated.     

HUMBOLDT'S MEXICAN TEXTS AND LANDSCAPES*

ABSTRACT. While in New Spain from 1803 to 1804, Alexander von Humboldt interacted with some of its landscapes and the texts that represented them. Analysis of those interactions regarding the Basin of Mexico and the Gulf lowlands demonstrates what purely text‐based studies of the production of places cannot: The contrasting landscape elements and patterns that had emerged over millennia during precolonial times in those two places, their relative degrees of depopulation during the colonial era, and the relative degrees of rigor Humboldt applied to interacting with the resulting landscapes and the texts that represented them greatly affected his representations of those places in his 1811 Essai politique sur le royaume de la Nouvelle‐Espagne. His representations of the precolonial Basin of Mexico as productively developed and of the precolonial Gulf lowlands as pristine have influenced the transformations of those places in the two centuries after New Spain became the Mexican republic through its wars of independence (1810–1821).     

Groundwater-flow modeling in the Yucatan karstic aquifer, Mexico

The current conceptual model of the unconfined karstic aquifer in the Yucatan Peninsula, Mexico, is that a fresh-water lens floats above denser saline water that penetrates more than 40 km inland. The transmissivity of the aquifer is very high so the hydraulic gradient is very low, ranging from 7–10 mm/km through most of the northern part of the peninsula. The computer modeling program AQUIFER was used to investigate the regional groundwater flow in the aquifer. The karstified zone was modeled using the assumption that it acts hydraulically similar to a granular, porous medium. As part of the calibration, the following hypotheses were tested: (1) karstic features play an important role in the groundwater-flow system; (2) a ring or belt of sinkholes in the area is a manifestation of a zone of high transmissivity that facilitates the channeling of groundwater toward the Gulf of Mexico; and (3) the geologic features in the southern part of Yucatan influence the groundwater-flow system. The model shows that the Sierrita de Ticul fault, in the southwestern part of the study area, acts as a flow barrier and head values decline toward the northeast. The modeling also shows that the regional flow-system dynamics have not been altered despite the large number of pumping wells because the volume of water pumped is small compared with the volume of recharge, and the well-developed karst system of the region has a very high hydraulic conductivity. Electronic Publication     

To afforest the desert with the technology of peat composed of rotten mosses and the sustainable development of the oases

Only by providing the good conditions for the growth of plants can a favorable ecologicalenvironment on which human beings rely for existence be created. The upside-down-T dou-ble-layer water-conserving afforestation way is developed according to the situation of the short-age of water resources, low soil fertility and vast land in the arid areas. The characteristics of theafforestation way are to change the microenvironment in the root area of the plants, provide thefavorable conditions for the growth of plants, and reduce the necessary conditions for the growth ofplants in large areas in the arid regions. Meanwhile, the size of its water-conserving layer can bechanged according to the size of the planted trees. The different ways of the bottom wa-ter-conserving layer can be used according to the requirements. The afforestation way is suitablefor planting trees on a small scale and also for afforesting on a large scale under the adverse cir-cumstances in the arid areas, and has been effectively used in the afforestation in the hinterland ofTaklamakan Desert and the southern marginal zone of Gurbantonggut Desert. The prospects ofthe afforestation way are broad in afforestation and desertification control in the desert regions.     

西藏自治区土壤侵蚀特点及现状

西藏自治区地域辽阔,土壤侵蚀复杂多样。本文在野外调查的基础上,对西藏自治区土壤侵蚀特点作了全面论述,并对西藏自治区不同类型土壤侵蚀区的土壤侵蚀现状做了较全面的分区评价。同时取雅江中游地区19个县作为典型区域,利用1999年1:20万TM遥感图像土壤侵蚀解译结果,对该典型区域的土壤侵蚀现状作了定量评价。最后根据评价结果,对西藏自治区土壤侵蚀的发展趋势做了预测。     

台湾西南部泥岩土地利用型态与环境劣化趋势之分析

台湾泥岩恶地因其特殊之土壤理化性质及区域微气候的相互恶性循环，衍生生态环境等问题。在以往之35年，裸化面积从1967年的2532hm^2，至2001年11月已扩大为15539hm^2。其表土大量流失、崩塌、河川含砂量激增、植被退化与微气候变异等破坏，更显示泥岩之环境劣化问题。以SPOT卫星影像判识泥岩裸露面积，探讨不同时期之地景变异，并应用地景生态理论量化泥岩地表不同土地利用之空间结构变化，分析地景结构变迁之生态内涵与生态指标意义。因子分析结果其主要变异为多样性因子与形状破碎型因子所影响，而应用马可夫链模式计算出不同时期之土地利用变迁内涵，此结果搭配指标分析可解释泥岩裸露面积与竹林面积皆持续扩大，乃由人为土地利用之活动及植被变迁所引起。     

五里冲水库--治理和利用喀斯特溶洞的范例

滇南蒙自五里冲水库，系充分利用盲谷地形、地下隐蔽喀斯特大厅、地下暗河等自然条件，扬长避短，通过明堵暗灌、高压灌浆、构建防渗帷募等特殊综合工程手段建造的无大坝型水库。该区地质情况复杂，喀斯特十分发育，先后投入大量钻探、平硐及基础地质调查工作量，采和合适的防漏、防渗工程。1996年竣工下闸蓄水后水位持续上升，达到设计要求，为蒙自工农业经济发展提供条件，亦为在我国南方复杂喀斯特地区构建大、中型水库闯出新路。