A qualitative and quantitative evaluation of experimental model catchment evolution

Due to the geological time scales required for observation of catchment evolution, surrogates or analogues of field data are necessary to understand long‐term processes. To investigate long‐term catchment behaviour, two experimental model catchments that developed without rigid boundaries under controlled conditions are examined and a qualitative and quantitative analysis of their evolution is presented. Qualitatively, the experimental catchments have the visual appearance of field scale data. Observation demonstrates that changes in catchment shape and network form are conservative. Quantitative analysis suggests that the catchments reach an equilibrium form while a reduction in the channel network occurs. While the catchments are laboratory scale models, the results provide insights into field scale behaviour. Copyright © 2003 John Wiley & Sons, Ltd.     

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).     

衡阳南岳区农村居民点用地合理布局分析

城镇化水平的快速推进和社会主义新农村建设的开展给建设用地供给和耕地保护形成了巨大的压力。农 村居民点用地普遍散乱、粗放的现象为挖掘现有建设用地潜力,少占耕地提供了可能。以衡阳南岳区为例,应用GIS 空间分析与景观指数分析等方法,在分析社会经济、自然地理和生产环境三方面的主要因素对南岳区农村居民点 用地布局的影响后,提出引导南岳区农村居民点合理布局的对策与建议。     

南昌地区建设用地空间扩展的广义转移概率模型建设与应用研究

对南昌地区城市发育约束因素的分析的基础上,基于非城市像元所处的城市化梯度、距离最近建成区斑块的距离、最近建成区斑块的规模、边缘像元的邻域水平等4个城市景观格局因子和道路及地形等两个社会经济和自然影响因子,构建了广义转移概率模型,并开展了相关的动态模拟研究。表明,与传统模拟方法相比,该模型具有比较理想的精度水平,模拟结果能够很好地反映南昌地区今后城市建设用地发展趋势,提出的模型手段改进设计获得了令人满意的效果,是对现行城市景观动态模拟研究工作的一个重要的方法论补充和完善。     

内蒙古典型草原和草甸草原相对花粉产量重估

相对花粉产量（RPP）是利用地层花粉数据定量重建古植被的重要参数,但目前估算的不同地区同一植物类型的RPP多存在差异。为了解植被盖度计算方法对花粉产量的影响,本项研究利用卫星影像数字化重新计算了内蒙古锡林郭勒典型草原和乌拉盖草甸草原采样点周边100 m以外的植被数据,利用ERV模型重新估算了主要花粉类型的RPP,并运用景观重建算法（LRA）进行了检验。锡林郭勒典型草原ERV模型分析显示,ERV子模型1结合1/d距离加权法与植被-花粉数据拟合度最高,得到的相关花粉源范围（RSAP）为1470 m;以蒿属为参照种（RPP=1±0）,各科属RPP依次为藜科（0.53±0.03）、十字花科（0.17±0.01）、唐松草属（0.14±0.02）、菊科（0.09±0.01）、莎草科（0.08±0.006）、委陵菜属（0.07±0.01）、禾本科（0.050±0.003）。乌拉盖草甸草原ERV模型分析显示,ERV子模型1结合Prentice距离加权法与植被-花粉数据拟合度最高,得到的RSAP为770 m;以蒿属为参照种（RPP=1±0）,各科属RPP依次为藜科（5.85±0.58）、蓼科（5.27±0.37）、石竹科（5.15±0.47）、莎草科（4.16±0.13）、菊科（1.63±0.09）、百合科（0.49±0.08）、唇形科（0.38±0.06）、禾本科（0.200±0.004）。重估的RSAP和RPP均与首次估算时存在差异,表明植被盖度计算方法确实会影响RSAP和RPP。景观重建算法对RPP检验结果表明,卫星影像数字化估算的RPP重建的植被盖度与实际植被的相关性更高。

     

基于DEM的交通线文化景观感知与功能分段研究——紫荆关长城景观的实证

在已有景观感知度概念和模型基础上,根据景观规模和特征将交通线某一具体位置的景观感知度划分为单点景观、多点景观和组景观感知度,并提出了基于集合表达的交通线景观感知度模型,以解决在一组特定的线性空间单元或区域上开展景观感知的研究和计算问题。以紫荆关长城文化景观为例,利用DEM进行景观视域分析,并引入资源价值、遗存现状等权重因子,实现了紫荆关附近公路和铁路线的景观感知度定量计算。根据景观感知度的空间格局,准确划分了敌台、烽火台和马面等单点景观、墙体景观及各类组景观和综合景观的最佳感知功能路段和最佳观赏位置。总体来看,紫荆关附近的公路线可感知位置连续性更强,铁路线高感知位置相对离散,公路感知效果整体优于铁路感知。交通线景观感知度模型特别适合用于大型造型地貌、宏伟建筑群等景观感知分析,是对旅游景观规划设计方法的一种扩充,能够将旅游景观规划设计从旅游地内部拓展到旅游地外围,对于提高旅游景观导引设计的精准性、提升旅游文化传播效率和增加传播途径等均有理论参考意义和实践应用价值。     

韩国济州岛柑橘园景观与空间分布演变（1526—2019年）

韩国济州岛的柑橘园景观具有重要的文化遗产价值,是当地人利用济州岛特殊的气候、水文、植被环境所塑造的独特农业景观。16世纪朝鲜王朝建立柑橘进贡制度,济州官府设置柑橘园,此后至今,济州岛柑橘园区域分布与地理景观都呈现较大变迁。文章结合气候、水资源等自然因素与韩国柑橘产业政策、市场、社会变化与技术进步等人文因素,分析16世纪以来济州岛柑橘园景观与空间分布变化,探讨济州岛柑橘生产空间变迁原因与驱动力。结果显示：16世纪至2019年,济州岛柑橘生产经历了发展、没落、强力复兴的大起大落发展历史,呈现从北到南的生产空间大迁移,柑橘生产空间逐渐扩大。济州岛的柑橘园生产经历从朝鲜时期的官府果园到现代观光体验农场的转变。柑橘生产空间变迁与地理景观变化的原因与驱动力较复杂,水资源是影响朝鲜时期柑橘园分布的主要自然因素。社会制度、交通与市场是16世纪以来影响柑橘园生产空间扩展的主要人文因素,在近500年的柑橘生产空间发展变迁的过程中,人文因素不断加强,影响柑橘空间与地理景观的优化调整。20世纪70年代以来,水资源开发技术的进步改变了现代柑橘园生产空间分布格局。对济州岛柑橘园长时段的生产空间与地理景观变化及其作用机制的研究,可以为中国传统柑橘栽培地区打造具有地方特色柑橘园文化景观与民俗、文化产品,以及中国柑橘产业的升级发展提供参考。     

北京西部山地景观生态整治与景观规划--以北京房山区史家营乡的典型研究为例

北京市西部山区是因矿区开发使山地景观生态环境破坏的重点地区,在北京市生态环境整治与建设中具有十分重要的典型意义。不合理的煤炭资源开采导致了矿点密度大,采空塌陷区分布广,水资源急剧减少,水质污染严重,植被大规模遭破坏,水土流失严重,泥石流等灾害加重以及煤尘污染问题突出等一系列环境问题,呈现出山地生态系统遭受严重破坏的景观生态特征。本文以史家营为例,在典型调查的基础上,规划了景观生态环境恢复与重建区、种植养殖和观光生态农业示范区、果粮养殖生态农业区、林草放牧生态畜牧业示范区、生态旅游区的五个景观规划区域,探讨了生态型矿业、中低山特色生态农业和生态旅游发展的产业发展模式,并初步提出了景观生态整治的措施。     

Local provenance in rehabilitation of degraded landscapes: a case study from the Hawkesbury–Nepean catchment, Australia

Throughout Australia thousands of volunteers are engaged in Landcare projects that should help rehabilitate degraded landscapes. Many of these projects involve tree planting, but their seed is not necessarily of local provenance. Based on a survey of 85 Landcare groups working in the Hawkesbury–Nepean catchment, data were collected about Landcare groups' knowledge of their seed source, understanding of local provenance and the ecosystem in which they were planting trees and the source of funding for their projects. The findings from the study indicate that about one in five (21%) of the groups surveyed that introduced plant material were not aware of local provenance issues. Indirect indications were that a large number of Landcare groups state-wide may be doing more harm than good to the landscape while trying to rehabilitate it. The data also showed that one in seven (13%) of the groups funded by the Australian Government through the Natural Heritage Trust (NHT) had limited awareness of local provenance issues. With millions of dollars being spent on 'works on the ground', it would be prudent to allocate some funds to document and monitor current Landcare activities, so that the environmental outcomes can be quantified and more effective Landcare policies can be developed in the future.