南麂列岛旅游生态足迹与生态效用研究   总被引：6，自引：0，他引：6  

周年兴  林振山  黄震方  程春旺 《地理科学》2008,28(4):571-577

旅游生态足迹与生态效用分析是从全球角度评价旅游业可持续发展的重要方法,两者相互补充。以南麂列岛国家海洋自然保护区为例,计算并分析了2002年的旅游生态足迹与生态效用。结果表明:① 南麂列岛旅游者人均生态足迹为0.031 hm²,是全国平均水平的1/3;② 叠加了旅游者生态足迹后,南麂列岛生态赤字达939.38 hm²;③ 南麂列岛旅游业单位生态足迹产值为14 221元/ hm²,是全球平均水平的1.8倍,却低于其渔业的单位生态足迹产值;④ 南麂列岛旅游业全年标准CO₂排放量为2 438.7 t,生态效用为0.128 kg/元;⑤ 南麂列岛生态效用略优于全球平均水平,是全国平均水平的3.1倍,但距全球理想的生态效用仍有一定距离。南麂列岛较低的生态足迹和较好的生态效用主要是由于其旅游开发规模适当,管理到位,倡导生态旅游,同时大部分旅游者为短程游客。旅游生态足迹和生态效用不仅在理论上深化了可持续发展的内涵,在技术上也是可持续发展的重要指标体系。  相似文献   

利用视线加速度数据恢复月球近区重力异常的研究   总被引：1，自引：0，他引：1       下载免费PDF全文

沈飞  隋铭明  李建成 《地球物理学进展》2008,23(6):1758-1763

本文阐述了利用分步最小二乘方法拟合视线加速度来确定月球重力异常的原理和计算步骤,并利用"Lunar Prospector"扩展任务实测的视线方向加速度数据计算了月球近区的重力异常.最后将计算结果和现今最高阶次的月球重力场模型LP165进行了比较和分析,得出标准差在纬度-75°～75°范围内为±27.354 mGal,75°～85°和-85°～-75°范围内为±61.965 mGal的精度,从而验证了该解算方法的可行性和可靠性.  相似文献   

Tertiary crustal shortening and peneplanation in the Hoh Xil region: implications for the tectonic history of the northern Tibetan Plateau     

《Journal of Asian Earth Sciences》2002,20(3):211-223

The Hoh Xil Basin is the largest Cenozoic sedimentary basin in the hinterland of the Tibetan Plateau. Tertiary sedimentary strata 5.8 km thick, comprising the Fenghuoshan, Yaxicuo and Wudaoliang groups, provide compelling evidence concerning the crustal shortening, erosion and peneplanation of the northern Tibetan Plateau. The basal Fenghuoshan and overlying Yaxicuo groups span the Eocene-Early Oligocene stratigraphically, and have been dated by magnetostratigraphy as 56–30 Ma old. Both groups are composed of terrigenous rocks. Provenance analysis of sandstones and conglomerates demonstrates that Permian and Triassic strata in the Tanggula Orogenic Zone in the south were the source for the Fenghuoshan Group. In contrast, the Carboniferous–Triassic strata in the Tanggula, Bairizhajia, and Heishishan-Gaoshan orogenic zones in the north, were the source for the Yaxicuo Group.During the Late Oligocene, northern Tibet underwent strong north–south crustal shortening (∼43%) and thickening. Extensive erosion, which occurred over the entire plateau surface near the end of the Oligocene, resulted in development of a peneplain surface. The latter is overlain by the Early Miocene Wudaoliang Group, composed of fresh water limestones. These are exposed both on summit surfaces, as well as on the valley floors, showing that a phase of differential uplift occurred after the deposition of the Wudaoliang Group. This post-Miocene differential uplift was due to regional extension, in a region of overall shortening. Even though we have not succeeded in obtaining conclusive data about the exact timing of phases of rapid uplift of the Tibetan Plateau, it is most likely that the major phase of uplift occurred during the Late Oligocene.  相似文献   

Evaluation of various vertical mixing parameterizations in a tropical Pacific Ocean GCM     

《Ocean Modelling》2002,4(3-4):291-311

Coupled general circulation models (GCMs) have had weak El Niño/Southern Oscillation variability that has been attributed to a diffuse thermocline in the modeled equatorial Pacific Ocean. Consequently, there have been many attempts to improve the thermocline by developing new or improved ocean vertical mixing schemes. This paper investigates the influence of gradient Richardson Number-based vertical mixing scheme profiles in a tropical Pacific Ocean GCM. It has been common for vertical mixing schemes to be assessed in tropical Pacific Ocean models that have a limited latitudinal domain bounded by zonal walls with sponge layers. However, recent work has shown that warm surface water can accumulate in these models and stop them from achieving the observed sharp equatorial thermocline. The present model employs a parameterized wall heat transport scheme that prevents warm surface water from accumulating. Thus we are able assess the influence of vertical mixing profiles in an ocean model that does not allow warm surface water to accumulate and influence the thermocline.In this paper we evaluate the equatorial performance of three different Richardson number (Ri)-based vertical mixing profiles: an integer power (IP) profile based on the observations of Peters, Gregg and Toole; a form of the Pacanowski and Philander profile modified to have low background mixing; and the Max Planck Institute profile. With the accumulation of warm surface water prevented, each of these profiles is able to achieve a sharp thermocline. When compared with observations, the IP profile achieves a better upwelling velocity distribution. We also examine the influence on equatorial performance of very high mixing coefficients at low Richardson number, and of low background mixing coefficients.  相似文献   

Distribution characteristics of the additional vertical stress on a shaft wall in thick and deep alluvium: a simulation analysis     

Wu  Yun  Zhu  Shu-yun  Li  Xiao-zhao  Zhang  Hui  Huang  Zhen 《Natural Hazards》2019,96(1):353-368

Natural Hazards - In order to investigate the mechanisms of shaft lining deformation of coal mines in thick and deep alluvium, we selected Qianyinzi coal mine in the Huaibei mining area in the east...  相似文献   

Geological cycling of potassium and the K isotopic response: insights from loess and shales     

Li  Weiqiang  Li  Shilei  Beard  Brian L. 《中国地球化学学报》2019,38(4):508-516

Shales are a major sink for K into seawater delivered from continental weathering, and are potential recorders of K cycling. High precision K isotope analyses reveal a > 0.6 ‰ variation in δ⁴¹K values (⁴¹K/³⁹K relative to NIST SRM 3141a) from a set of well characterized post-Archean Australian shale (PAAS) samples. By contrast, loess samples have relatively homogenous δ⁴¹K values (− 0.5 ± 0.1 ‰), which may represent the average K composition of upper continental crust. Most of the shales analyzed in this study have experienced K enrichment relative to average continental crust, and the majority of them define a trend of decreasing δ⁴¹K value (from − 0.5 to − 0.7 ‰) with increasing K content and K/Na ratio, indicating cation exchange in clays minerals is accompanied by K isotope fractionation. Several shale samples do not follow the trend and have elevated δ⁴¹K values up to − 0.1 ‰, and these samples are characterized by variable Fe isotope compositions, which reflect post-depositional processes. The K isotope variability observed in shales, in combination with recent findings about K isotope fractionation during continental weathering, indicates that K isotopes fractionate during cycling of K between different reservoirs, and K isotopes in sediments may be used to trace geological cycling of K.

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西北太平洋边缘海区海面变化多尺度解析及空间分异   总被引：2，自引：1，他引：1  

俞肇元  袁林旺  闾国年  谢志仁  张季一  梅伟长 《地理研究》2009,28(6):1644-1655

利用MODWT对西北太平洋边缘海区8站位1965~2005年验潮序列进行多尺度分解,讨论了该区域海面变化多尺度波动特征及空间分异。结果显示年周期组分振幅随纬度增大而逐渐增大,半年周期组分振幅以中国沿岸最大,其余站位相对较小。年际尺度的波动中ENSO信号与1~2年尺度的准周期波动存在模态混叠现象,表现为对序列构形和不同时段的相关关系的影响。利用ICA方法从小波分解的年际尺度和信号中分离出的ENSO信号,表明不同纬度海面对ENSO事件的响应整体上呈现向高纬衰减的变化特征。基于小波相似性的分析结果显示,低纬各站海面对ENSO在各尺度上均呈现出显著的负相关,而中高纬地区则呈现出正相关。1980年之前和之后中高纬地区的海面对ENSO的响应出现了显著的差异,这可能与ENSO自身频率的调整有关。  相似文献   

基于元分维模型的江苏城镇体系空间均衡特征分析   总被引：2，自引：0，他引：2  

崔世林  龙毅  周侗  王丽琴 《地理科学》2009,29(2)

基于滑动窗口的局部分维分析方法--元分维模型,采用2005年江苏省城镇基础数据,对江苏省1 850个城镇及街道办的空间均衡程度进行定量测度,结果表明:①江苏城镇体系空间均衡程度差异明显,自南向北存在一定程度的空间梯度递减,其中江苏南部城镇分布最为密集且较为均衡,江苏中部次之,而江苏北部除徐州市区外.均衡程度较低;②江苏城镇分布上东部比西部均衡;③江苏城镇轴线集中发展的分布特征突出,沿长江分布的无锡、常州、苏州、镇江、扬州、泰州、南通、南京8个地区城镇分布密集,且均衡程度较高;④城镇体系的空间均衡程度与城市化水平基本一致.实验证明,元分维模型可以用于定量分析特定尺度下的城镇局部空间均衡程度的差异.  相似文献   

Analysis of water consumption using a regional input–output model: Model development and application to Zhangye City,Northwestern China     

Y. Wang  H.L. Xiao  M.F. Lu 《Journal of Arid Environments》2009,73(10):894-900

Based on a regional input–output model, we developed a method to identify the relationships between production activities and the related water consumption, as well as the relationships established between different sectors concerning water resources (i.e. indirect consumption). This method is applied to Zhangye City, an arid area of northwestern China that is characterized by water shortages. Our results confirm that although Zhangye suffers from a serious water shortage, the city's economic structure is based on sectors that consume large quantities of water. On the one hand, food production and forestry consume large quantities of water, reflecting the large scale of these water-intensive forms of land use. On the other hand, the industrial and service sectors use a smaller amount of water directly in production, but to produce the intermediate inputs that they incorporate into their production processes, a high consumption of water is often necessary. At present, there is no evidence that the city alleviates its water scarcity by importing virtual water in the form of economic inputs produced in other regions, suggesting that planners should include both direct and indirect water consumption in their resource allocation planning.  相似文献   

我国人文地理学研究方法多样化问题   总被引：17，自引：3，他引：14  

汤茂林 《地理研究》2009,28(4):865-882

从我国地理学研究存在的问题入手,切入我国人文地理学研究的方法和方法论问题。自1970年代以来,欧美人文地理学研究范式和方法论逐步多样化,这可以作为我们发展人文地理学方法的一个参考。正是基于对实证主义地理及其方法论局限性的认识,结构主义(包括马克思主义)、人文主义、女性主义、后现代化主义和后结构主义相继登场。中国作为一个向现代社会全面转型的发展中国家,地理格局异常复杂。结果是现代性问题与后现代问题并肩前行,发达和欠发达有关的问题同时存在。对这样复杂的地理景观所进行的人文地理学研究,较多地采用了基于实证主义方法论的空间科学传统,对塑造这一景观的人未能给予足够的关注。因此,我国的人文地理学研究迫切需要方法论和方法的多元化。  相似文献