Street networks in relation to landforms: Implications for fast-growing cities简

In addition to socio-economic factors, major landforms may affect the city structure and urban form. Here we show that landforms have significant effects on the city shape and street patterns of the fast-growing Iranian cities of Dezful （a river） and Khorramabad （moun- tains and valleys）, but no clear effects on the cities of Yazd and Nain. Also, where the street orientation is peaked, the Gibbs/Shannon entropy （a measure of dispersion or spread） is low, but increases as the distribution becomes more uniform because of landform constraints. The streets in the old inner parts of all the cities are, on average, shorter and denser （more streets per unit area） than the streets of the newer outer parts. The entropies of the outer parts are also greater than those of the inner parts, implying that the street-length distribution gradually becomes more dispersed or spread as the city expands. All these cities have been fast growing in the past decades, with the newer outer parts expanding rapidly. As shown here, the rapidly formed outer parts （with greater dispersion in street patterns） have significantly different textures from those of the older inner parts, indicating different functionality and growth processes. These quantitative methods for street-network analysis can be used worldwide, particularly for analysing the effects of landforms on city shape and texture.     

GARDENS ARE US,WE ARE NATURE: TRANSCENDING ANTIQUITY AND MODERNITY*

ABSTRACT. The history of gardens and the history of humans are linked inextricably, especially in the context of environment. As people and their institutions have changed, so too have gardens. This brief essay illustrates some important aspects in the evolution of gardens, exploring three seemingly discrete, but actually interconnected, notions: the antiquity of gardens, combining archaeological data with ethnographic parallels; the role of gardens in the changing spatial manifestations of agriculture, from dump heaps to amber waves of grain; and the transformation of domestic space, the literal and figurative reconstruction of garden fences into house walls. Changes are discussed as inadvertent products, rather than as consequences of deliberate actions. Modern ideas about categorizing landscapes are challenged further. The nature/culture dualism is a myth even at the household scale, as is our traditional way of looking at the world.     

Characterizing Non-Industrial Private Forest Landowners' Forest Management Engagement and Advice Sources

Non-industrial private forestland (NIPF) owners have options for engagement by following management strategies that reduce wildfire risk on their forestlands. Forest management engagement is a broad term with underlying categories and management implications. To better understand these categories, we examine interview data on the engagement of forest landowners from a case study of private forestland owner perspectives in northeast Oregon, USA. NIPF landowners outline two types of forest management engagement, one for property and one for community-focused forestland management. NIPF owners describe actions for engagement in public forestland management and how these actions differ from engagement in private management. Additionally, NIPF owners establish barriers to engagement in both public and private forestland management. Our findings can be used to better identify unengaged private forestland owners in the U.S. West, informing the design and implementation of extension and outreach for NIPF owners.     

新疆农业景观格局演变对其生态系统服务价值的影响

结合遥感、地理信息系统、景观生态学和空间分析等理论,分析了新疆地区2000~2015年农业景观格局的时空动态变化特征,测算了农业生态系统服务价值,通过相关分析进一步研究了农业景观格局与生态系统服务价值的关联,为促进区域土地资源合理利用和生态农业发展提供科学依据。结果表明,新疆农业生态系统正朝着多样化、稳定化的方向发展;农业生态系统服务价值显著增长,但区域间的价值差异较大,呈现北疆高南疆低的分布格局;景观面积、斑块数和景观形状对新疆地区农业生态系统服务价值影响较大且均呈现明显正相关关系。     

山东枣庄熊耳山崮形地貌成因及地质景观保护

山东枣庄熊耳山国家地质公园内,具双龙大裂谷、抱犊崮国家级森林公园、崮形地貌、崩塌地质遗迹、龙床水库等自然地质景观;地质地貌景观具重要的地学研究与观赏价值,挖掘地质景观资源,应遵循在保护中开发、在开发中保护的原则,此是公园管理部门一项长期的任务。     

黔东南苗岭国家地质公园的旅游地质景观特征和类型

在对贵州黔东南苗岭国家地质公园区的旅游地质景观实地调查研究的基础上,指出其旅游地质景观类型具有观赏与休闲性、奇异与独特性、多样性、古老性、科学性、不可再生性和文化特性;其类型有地层剖面大类、地质构造大类、生物化石大类、地貌景观大类、水体景观大类、环境地质遗迹景观大类和其他旅游地质景观。其丰富多彩的旅游地质景观为旅游开发提供了物质基础,旅游开发潜力大。     

Wind Power in View: Energy Landscapes in a Crowded World

Books reviewed:

Rayner, John N. Dynamic Climatology: Basis in Mathematics and Physics

Blair, Alasdair and Hitchcock, David. Environment and Business

Black, Brian. Petrolia: The Landscape of America's First Oil Boom

Sharma, Martha B. and Elbow, Gary S. Using Internet Primary Sources to Teach Critical Thinking Skills in Geography

Klemen?i?, Mladen (ed.) Atlas Europe

Kliot, Nurit and Newman, David Geopolitics at the End of the Twentieth Century: The Changing World Political Map

O’Sullivan, Patrick M. The Geography of War in the Post – Cold War World

Duany, Andres, Plater-Zyberk, Elizabeth, and Speck, Jeff. Suburban Nation: The Rise of Sprawl and the Decline of the American Dream

Kayden, Jerold S. Privately Owned Public Space: The New York City Experience

Borjas, George J. Heaven's Door: Immigration Policy and the American Economy

Andreas, Peter. Border Games: Policing the U.S.-Mexico Divide

England, John. Retail Impact Assessment: A Guide to Best Practice

Outtes, Joel. O Recife: Gënese do Urbanismo, 1927 – 1943 (Recife: The Birth of Urbanism, 1927 –1943)

Njoh, Ambe J. Urban Planning, Housing, and Spatial Structures in Sub-Saharan Africa: Nature, Impact, and Development Implications of Exogenous Forces

Hanson, Philip and Bradshaw, Michael (eds.) Regional Economic Change in Russia

Pyne, Stephen J. Book Review Commentary: A response to Terence Young's review of Stephen J. Pyne's How the Canyon Became Grand     

Tile drainage causes flashy streamflow response in Ohio watersheds

Artificial subsurface (tile) drainage is used to increase trafficability and crop yield in much of the Midwest due to soils with naturally poor drainage. Tile drainage has been researched extensively at the field scale, but knowledge gaps remain on how tile drainage influences the streamflow response at the watershed scale. The purpose of this study is to analyse the effect of tile drainage on the streamflow response for 59 Ohio watersheds with varying percentages of tile drainage and explore patterns between the Western Lake Erie Bloom Severity Index to streamflow response in heavily tile-drained watersheds. Daily streamflow was downloaded from 2010 to 2019 and used to calculated mean annual peak daily runoff, mean annual runoff ratio, the percent of observations in which daily runoff exceeded mean annual runoff (T_Qmean), baseflow versus stormflow percentages, and the streamflow recession constant. Heavily-drained watersheds (>40% of watershed area) consistently reported flashier streamflow behaviour compared to watersheds with low percentages of tile drainage (<15% of watershed area) as indicated by significantly lower baseflow percentages, T_Qmean, and streamflow recession constants. The mean baseflow percent for watersheds with high percentages of tile drainage was 20.9% compared to 40.3% for watersheds with low percentages of tile drainage. These results are in contrast to similar research regionally indicating greater baseflow proportions and less flashy hydrographs (higher T_Qmean) for heavily-drained watersheds. Stormflow runoff metrics in heavily-drained watersheds were significantly positively correlated to western Lake Erie algal bloom severity. Given the recent trend in more frequent large rain events and warmer temperatures in the Midwest, increased harmful algal bloom severity will continue to be an ecological and economic problem for the region if management efforts are not addressed at the source. Management practices that reduce the streamflow response time to storm events, such as buffer strips, wetland restoration, or drainage water management, are likely to improve the aquatic health conditions of downstream communities by limiting the transport of nutrients following storm events.     

A Review of “Breathing Space: How Allergies Shape Our Lives and Landscapes”

This paper expands the human capital model to compare the migration propensities of Cubans, Mexicans, and Puerto Ricans within the U.S. between 1985 and 1990. Using the 5% PUMS from the 1990 U.S. Census, both aggregate migration streams and micro-level migration propensities are estimated for Cubans, Mexicans, and Puerto Ricans. The effects of personal factors, the economic environment, and the presence of fellow nationals are examined in the context of larger geographic patterns, and discussed in terms of each nationality's immigration history and cultural context.

While many factors effect migration behavior similarly, there are notable differences in the way education, English fluency, and unemployment rate affect migration propensity of the native-born and foreign-born of each nationality. Differences are also apparent at the macro-level. Puerto Ricans show signs of dispersing out of New York; Mexicans are redistributing within the Southwest; and Cubans are re-concentrating in Florida. Both levels of analysis point to how immigration history, settlement patterns, and cultural context influence migration behavior. The results demonstrate the benefits of using an expanded human capital approach to explain migration differences, and highlight the diversity of population redistribution occurring within Hispanic nationalities.     

历史文化名城名胜组景的时空演变特征研究——以金陵四十八景为例

名胜组景是一定地域范围内景观的组合,是历史文化名城的重要城市地标和旅游资源。以南京的金陵四十八景为例,研究名胜组景的时空演变特征。研究发现:金陵古代名胜组景依赖于自然地理环境,密集分布在长江、钟山、秦淮河等山脉和河流附近,同时也受人文地理界线的影响,较集中于南京城墙内;民国至当代的金陵四十八景的空间分布呈现东进南延北拓态势,逐步扩散至人文地理边界以外的外城郭,进而扩散到郊区县市(江北、高淳、溧水)。名胜组景的这种时空变迁特征与城市变迁存在强烈的关联。历史文化名城的组景景观可划分为自然景观和人文景观。金陵四十八景的时间演进过程中呈现自然景观数量减少、人文景观数量增多的趋势,景观景名、排序等存在较大的差异。古今游憩偏好的变化、旅游需求的变化、历史文化景观的积累、宗教变革、土地利用、社会职能的转变、时代文化的差异都对此产生一定程度的影响。