The response of sedimentation in three varved lacustrine sequences to air temperature,precipitation and human impact

Human activity and climatic forcing have influenced sedimentation in three of Finland's deepest lakes during the last centuries. High-resolution sediment sequences of Lake Päijänne, Lake Pääjärvi and Lake Pyhäjärvi represent records of the last 440 years, 839 years and 633 years, respectively. The accumulation rates of dry matter, organic carbon and biogenic silica refer to changes in human activity in the catchments. However, they also reveal the importance of climatic forcing on lake sediment deposition. A significant correlation was found between instrumentally measured records of temperature (163 years) and precipitation (148 years), and varve thickness. Warm winter months indicating a short ice-cover period have the strongest control on varve thickness. This shows that wind-driven resuspension of littoral material is the forcing mechanism of climate on lake sediments. The long-term human-induced erosion pulses observed may even have magnified the climatic signals in some cases. Nevertheless, increased anthropogenic field erosion in the catchment, and the associated leaching of bioavailable nutrients, hampers the observation of climate signals, especially during the last 50 years, in the lakes studied.This is the second paper a series of papers published in this issue on high-resolution paleolimnology. These papers were presented at the Sixth International Palaeolimnology Symposium held 19-April, 1993 at the Australian National University, Canberra, Australia. Dr A. F. Lotter and Dr. M. Sturm served as guest editors for these papers.     

张其昀的地理思想和学术成就

张其昀(1901—1985)是我国近代地理学的创建者之一。他在地理教育以及人文地理学的广泛领域卓有建树。本文阐述他的学术成就,并探讨他的地理思想。     

Griffith Taylor Lecture,Geographical Society of New South Wales, 2004: Australia and the ‘State of Nature/Native’

This account sets itself against the binarism of physical versus cultural determinism that drives population–environment debate over people's place on the Australian continent. In reading back into colonial times, it evokes ‘our’ unresolved sense of relation to nature on a continent that has pressed awkward buttons since the time the botanist on Cook's Endeavour, Joseph Banks, first mused over the apparent contradiction on the east coast of human presence and uncultivated land. Australia's ‘state of nature’, including its inhabitants, elicited tensions in Anglo-Celtic peoples’ ambiguous relation with nature that have never gone away or been resolved. Indeed, I argue, against the background of what was considered in eighteenth-century Enlightenment thought to be a distinctly human separation from, and capacity to rise above, nature, that the Australian state of nature/native precipitated a crisis in prevailing ideas of ‘the human’. As consternation grew into the nineteenth century about the very capacity of Aboriginal people for improvement, and particularly for cultivation, I argue they challenged the basis upon which the unity of humankind had been assumed in Enlightenment thought. They could not be comprehended, according to the prevailing conception of racial difference, as a mere variety of the human. The radical idea of innate human difference may thus be understood as arising out of this incomprehension, as an attempt to account for the ontologically inexplicable difference of the Australian Aborigine. This lecture's excursion into the origins of ‘race’ is by way of highlighting the uncertainty of the divide between the human and non-human worlds. Imagining an entangled world of living things may help to craft fresh lines of debate about modes of environmental belonging and becoming on this continent that overcome the stale binaries and blind spots of Australia's population–environment debate.     

浅析城市人居环境的评价及优化措施--以苏州市为例

在探讨人居环境的概念、分类的基础上,采用以某一年为基准的相对比较法,构建城市人居环境评价指标体系。并以苏州市区为例,对1995～2000年苏州市区人居环境进行了较为详细的分析与评价。分析结果表明,尽管1995年以来苏州市区人居环境质量有较大的改善,但改善速度仍落后于经济增长速度,并且生态环境和居住条件改善更为缓慢。针对这些问题,从城市规划、城市化发展战略、城市生态环境建设等方面,提出了优化苏州市人居环境的具体措施。     

(ANTI)SOCIAL CAPITAL IN THE PRODUCTION OF AN (UN)CIVIL SOCIETY IN PAKISTAN*

ABSTRACT. Pakistan is home to some of the most widely admired examples of civil‐society‐based service‐delivery and advocacy groups. Pakistan has also spawned some much‐maligned nongovernmental actors with violent agendas. This article uses the social capital / civil society conceptual lens to view the modes of (anti)social capital mobilization that contribute to the civil and uncivil spaces of Pakistani society. The case examples of Jamaat‐e‐Islami, an Islamic revivalist organization, and the Human Rights Commission of Pakistan are used to understand the geography of social and antisocial forces in Pakistan. It is argued that the processes that mobilize social capital‐whether positive or perverse‐are multiscalar and that, in the Pakistani context, no compelling cultural or religious reason exists for the ascendance of one type of social capital over the other. Positive social capital can be mobilized to contribute to a more civil social discourse in Pakistan, given the right policy choices.     

Natural runoff changes in the Yellow River Basin

The driving factors of runoff changes can be divided into precipitation factor and non-precipitation factor, and they can also be divided into natural factor and human activity factor. In this paper, the ways and methods of these driving factors impacting on runoff changes are analyzed at first, and then according to the relationship between precipitation and runoff, the analytical method about impacts of precipitation and non-precipitation factors on basin's natural runoff is derived. The amount and contribution rates of the two factors impacting on natural runoff between every two adjacent decades during 1956-1998 are calculated in the Yellow River Basin (YRB). The results show that the amount and contribution rate of the two factors impacting on natural runoff are different in different periods and regions. For the YRB, the non-precipitation impact is preponderant for natural runoff reduction after the 1970s. Finally, by choosing main factors impacting on the natural runoff, one error back-propagation (BP) artificial neural network (ANN) model has been set up, and the impact of human activities on natural runoff reduction in the YRB is simulated. The result shows that the human activities could cause a 77×108 m3·a-1 reduction of runoff during 1980-1998 according to the climate background of 1956-1979.     

Geography's Human Resources over the Past Half‐Century*

This article examines trends over the past five decades in three human resource issues in geography: the production of new geographers; the size and diversity of the membership of the Association of American Geographers (AAG); and the topical specializations of geographers. The number of geography degrees awarded increased rapidly in the 1950s and 1960s, followed by a modest decline as baby boomers exited their college years. The number surged again in the 1990s, however, and it seems to have stabilized in recent years. AAG membership trends followed a similar trajectory and membership is currently poised to set a new record. The participation of women in the discipline has increased steadily over the past half‐century, but geography still lags the social and physical sciences in the share of women receiving bachelor's degrees. The participation of geographers from ethnic minority groups continues to be very low. The number of AAG specialty groups has doubled since their inception in 1978, and geographic information science (GIS) now occupies a prominent position within the discipline. Challenges in the coming years include increasing the diversity in geography, reducing the turnover in AAG membership, preparing for the imminent retirement of a large cohort of baby‐boom geographers, and reconnecting with nonacademic geographers.     

Advancing Human Geography at the Commencement du Siècle*

Human geography today exhibits unprecedented vitality and diversity. This survey first charts some major lines of research in the field in light of the ascendancy of critical theory, political economy, and poststructuralist thought, including feminism, the cultural turn, consumption, urban geography, and globalization. Next, it focuses on several “cutting‐edge” issues, such as race, postcolonialism, the social construction of nature, representations of space, and cyberspace. Finally, the article turns an eye toward the future, offering comments on the discipline's likely trajectories with regard to the blurring of traditional dualisms, methodological integration, and the lacunae of public policy and geographic education.     

人类活动对山地景观的影响研究进展

提出山地景观是由相互联系的相对海拔较高的景观组分镶嵌构成的异质性镶嵌体，具有景观类型呈垂直地带性分布格局、多样性高、形状复杂及廊道曲度大等特点重点从斑块复杂性、景观稳定性和多样性以及组成单元间空间联系等方面评述了人类活动对山地景观结构的影响，说明人类活动可增加或降低景观斑块的复杂性，破坏山地景观的稳定性并可改变山地景观的多样性．分析了人类活动对景观功能及动态的影响，探讨了人类活动对山地景观影响的研究重点。