四川省夹江县地质地貌资源现状及旅游可持续开发研究

对四川省夹江县主要地质地貌资源进行了叙述,分析了这些资源对旅游开发的重要意义,提出了开发的构想和保护原生地质地貌环境的建议。     

北京城市地质工作服务的新方向——地质遗迹景观资源的开发利用

本文在阐述北京城市地质工作和地质遗迹景观资源开发利用现状的基础上,通过地质公园建设实例,从推动地方经济发展和当地居民就业、加快城镇基础设施和生态环境建设、提升地学旅游品位和公众保护地质遗迹意识等三个方面论证了地质公园在保障城市经济健康和可持续发展中发挥的重要作用,从而有力阐明了开发利用地质遗迹景观资源是北京城市地质工作服务的一个新方向。本文还提出了今后北京地区地质遗迹景观资源开发利用对策。     

Characteristics of landscape information Tupu of the Yellow River swings and its subdeltas during 1855―2000

Based on the theories and methods of cartography on spatial pattern and temporal evolution in Geo-information Tupu (Carto-methodology in Geo-information, CMGI) and the quantitative measurements of pattern and process in landscape ecology, the methodology of landscape information Tupu in studying the swing process of the Yellow River (YR) over the Yellow River Delta (YRD) during 1855―2000 has been demonstrated. The main content includes (1) methodology of landscape information Tupu; (2) evolution process Tupu of YR rump channels; (3) evolution process Tupu of the 7 pieces of subdeltas in YRD during 1855―2000; (4) landscape information Tupu of the modern YRD and the current YRD; (5) landscape information Tupu of YR rump channels on the 7 pieces of subdeltas during 1855―2000; and (6) corridor-matrix landscape information Tupu by YR swings. The methodology of landscape information Tupu here is still primary but we hope that it could provide a new tool for exploring an integrated research on spatiotemporal approaches for landscape "pattern and process".     

试论生态旅游的生态化道路--以自然生态旅游区为例

生态旅游已成为当今世界旅游发展的潮流。然而，在生态旅游开发过程中，存在着众多的。非生态化”现象，尤其是在自然生态旅游区。分析当前自然生态旅游区旅游开发和建设中的“非生态化”现象，主要包括盲目开发，自然景观破坏严重；游客严重超载，生态环境受破坏；人造景观和设施泛滥，景观污染和趋同现象严重；管理和文明建设落后，文化景观功能退化或受损等。运用景观生态学原理和生态安全理论等，从景观功能分区、旅游生态管理容量、景观结构生态设计、景观生态安全格局构建、生态教育等方面提出自然生态旅游区的生态化道路。     

大都市空间扩展的廊道效应与景观结构优化*──以北京市区为例

由于存在城市中心梯度场和廊道效应梯度场,在单纯经济利益趋动下,城市本质上存在摊大饼倾向,这将严重破坏城市合理景观结构与生态平衡.文中运用廊道效应原理,研究人工廊道与自然廊道相互作用过程,结合北京中心市区不同时期空间扩展格局,分析城市景观8个方位廊道的扩展量、扩展速度及变化趋势,提出将自然廊道体系纳入北京大都市区规划,形成人工廊道与自然廊道相间分布的星状分散集团式景观格局,以有效阻止建成区摊大饼过程.     

Lateral translocation of soil plasma through a small valley basin in the Northaw Great Wood,Hertfordshire

The paper looks at the process of lateral translocation in a small valley basin from the Northaw Great Wood, Hertfordshire. The valley basin comprises four lithostratigraphic units (London Clay and Pebble Gravel, and the others a mixture of these two), which were initially established in the field by a rough assessment of texture. Particle size analysis validated the lithostratigraphic units as delineated in the field; it was found unnecessary to alter the boundaries of the units. Patterns of lateral translocation of silt and clay (measured by the hydrometer method) and the amorphous colloidal hydrous oxides and hydroxides of Al, Fe, Mn and Si (measured in oxalate solution by atomic absorption spectrophotometry) are inferred from balance sheets of the relative gains and losses of the materials. Materials from horizons formed in lithostratigraphic units derived from London Clay are balanced against a clay dilution factor; those from the lithostratigraphic unit of Pebble Gravel against the dilution of sand on a clay-free basis. The results lead to the following conclusions about the process of lateral translocation: it has been a significant contributor to soil development; larger amounts of material have moved down-slope towards the hollow than over the nose because there has, theoretically, been more throughflow in the hollow; for some materials there has been less down-slope transport in lower horizons owing to less throughflow in them.     

Pliocene aridity and Neogene landscape evolution recorded by a fluvial sediment system (Campaspe Formation) in northeast Queensland

Campaspe Formation, a surficial, fluviatile, sand-dominated unit, is extensively developed in the Charters Towers region of north Queensland where it covers an area of 11 000 km², overlying Paleozoic basement and erosional remnants of Paleogene Southern Cross Formation. In the northern part of its distribution, it is interlayered with, and overlain by, flows of Nulla Basalt. It is dated as mid-Pliocene, based on the 3.48 Ma age of the Myrrilumbing Flow interlayered with its upper part, an antiquity consistent with thin ferricrete locally developed at its surface. The formation defines the Campaspe Surface at an elevation of 200–440 m in the present landscape, falling gently from upland to the west towards the current channel of the Burdekin River. This surface is a relict alluvial plain little incised by easterly flowing tributaries of the Burdekin River and has survived, essentially intact, from the early Pliocene. Geometry of the formation is established from some 2000 mineral exploration drill holes and seismic profiling. It has an average thickness of some 60 m, reaching a maximum of over 200 m. It blankets a pre-existing, low relief landscape in which a basement ridge divides it into two sub-basins that mirror the present drainage. The formation consists of poorly sorted sandstone with minor conglomerate and siltstone, and contains paleosol horizons with associated calcrete. Matrix supported sandstone in the succession, indicates deposition in part from hyperconcentrated flows. Sandstones generally show poorly defined planar layering as typical of ephemeral overbank and terminal splay sediment bodies but beds with cross-lamination, indicating fluvial channel bed forms, are also present. They are characterised by pore-filling silt and mud, largely emplaced by post-depositional infiltration, such that the unit produces essentially no groundwater. Facies attributes are consistent with fluvial deposition in ephemeral, dry climate, distributary system, with inefficient cross-drainage discharge that induced aggradation, resulting in a substantial sediment body perched in the landscape. Framework grain compositions show the formation to be mineralogically mature, representing erosional debris derived from intense weathering in an earlier climatic regime recorded, at least in part, by duricrust developed in the fluviatile–lacustrine Southern Cross Formation of Paleogene age. Such duricrust intervals are now upstanding in the landscape, representing erosional remnants from inverted relief developed in a mid-Cenozoic, pluvial, landscape cycle. Paleoclimatic signature of the Campaspe Formation extends the record of Pliocene aridity, widely recognised elsewhere in Australia, to northeast Queensland. In large part the landscape of the Charters Towers district is relict from the early Pliocene and is in the process of readjusting to more pluvial climatic regimes. By implication, Pliocene aridity has, on a small scale, exerted a strong influence on the present physiography of Australian landscapes.     

Epigenetic gorges in fluvial landscapes

Epigenetic gorges form when channels that have been laterally displaced during episodes of river blockage or aggradation incise down into bedrock spurs or side‐walls of the former valley rather than excavating unconsolidated fills and reinhabiting the buried paleovalley. Valley‐filling events that promote epigenetic gorges can be localized, such as a landslide dam or an alluvial/debris flow fan deposit at a tributary junction, or widespread, such as fluvial aggradation in response to climate change or fluctuating base‐level. The formation of epigenetic gorges depends upon the competition between the resistance to transport, strength and roughness of valley‐filling sediments and a river's ability to sculpt and incise bedrock. The former affects the location and lateral mobility of a channel incising into valley‐filling deposits; the latter determines rates of bedrock incision should the path of the incising channel intersect with bedrock that is not the paleovalley bottom. Epigenetic gorge incision, by definition, post‐dates the incision that originally cut the valley. Strath terraces and sculpted bedrock walls that form in relation to epigenetic gorges should not be used to directly infer river incision induced by tectonic activity or climate variability. Rather, they are indicative of the variability of short‐term bedrock river incision and autogenic dynamics of actively incising fluvial landscapes. The rate of bedrock incision associated with an epigenetic gorge can be very high (>1 cm/yr), typically orders of magnitude higher than both short‐ and long‐term landscape denudation rates. In the context of bedrock river incision and landscape evolution, epigenetic gorges force rivers to incise more bedrock, slowing long‐term incision and delaying the adjustment of rivers to regional tectonic and climatic forcing. Copyright © 2008 John Wiley & Sons, Ltd.     

The importance of local‐scale openness within regions dominated by closed woodland

New and existing pollen data from Wales, UK, are used to assess the level of landscape openness at the regional and local scale. At the regional scale, the existing pollen data support the high‐forest model of vegetation structure by 6000 cal. yr. BC prior to any palynological signal for anthropogenic impact in the region. New data from two sites in southwest Wales follow the general regional pattern of early to middle Holocene vegetation succession, but are striking owing to maintenance of high non‐arboreal pollen percentages (NAPs) throughout the mid‐Holocene. It is argued that these NAPs indicate that a significant degree of openness can be found at the local level (and beyond the confines of the peat‐forming site) within regions characterised by closed woodland. It is possible that woodland development in these areas may have been suppressed by reduced drainage, although the role of grazing animals in maintenance of clearings cannot be assessed. Implications for this local degree of openness are discussed, in particular the significance of vegetation heterogeneity at the local scale for the construction of place or locale for prehistoric communities. Copyright © 2006 John Wiley & Sons, Ltd.     

INTERSTATE HIGHWAY EXIT MORPHOLOGY: NON-METROPOLITAN EXIT COMMERCE ON 1-75*

The commercial non-metropolitan exit clusters of America's interstate highway system exhibit regularities of basic form, scale, mix of services provided, and the ordinal placement of establishments relative to the exit proper. An examination of 354 exits serving 1-75 indicates the typical morphology of interstate exit clusters.