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991.
Global pet ownership, especially of cats and dogs, is rising with income growth, and so too are the environmental impacts associated with their food. The global extent of these impacts has not been quantified, and existing national assessments are potentially biased due to the way in which they account for the relative impacts of constituent animal by-products (ABPs). ABPs typically have lower value than other animal products (i.e. meat, milk and eggs), but are nevertheless associated with non-negligible environmental impacts. Here we present the first global environmental impact assessment of pet food. The approach is novel in applying an economic value allocation approach to the impact of ABPs and other animal products to represent better the environmental burden. We find annual global dry pet food production is associated with 56–151 Mt CO2 equivalent emissions (1.1%−2.9% of global agricultural emissions), 41–58 Mha agricultural land-use (0.8–1.2% of global agricultural land use) and 5–11 km3 freshwater use (0.2–0.4% of water extraction of agriculture). These impacts are equivalent to an environmental footprint of around twicethe UK land area, and would make greenhouse gas emission from pet food around the 60th highest emitting country, or equivalent to total emissions from countries such as Mozambique or the Philippines. These results indicate that rising pet food demand should be included in the broader global debate about food system sustainability.  相似文献   
992.
古尔班通古特沙漠是中国最大的固定、半固定沙漠,也是中国境内受西风环流影响最明显的沙漠之一.本文简介古尔班通古特沙漠风沙地貌的研究历史,综述区域风况和输沙势特征、主要沙丘类型分布格局、风沙物质来源、沙丘粒度特征、沙漠环境演变和纵向沙垄发育模式以及现代沙丘动态变化等方面的研究进展,指出研究中存在的问题并展望未来研究方向.  相似文献   
993.
Book Reviewed in this article:

Geographical Aspects of Health and Disease in India. Rais Akhtarand A.T.A. Learmonth, eds.

Antarctic Treaty System: An Assessment. Proceedings of a Workshop at Beardmore South Field Camp, Antarctica.

American Electoral Mosaics. J. Clark Archerand Fred M. Shelley.

Kompas op Suidwes-Afrika/Namibie. W.S. Barnard, ed.

Jerusalem in the 19th Century: The Old City. Yehoshua Ben-Arieh.

The World as a Total System. Kenneth E. Boulding.

A Social History of Housing 1815–1985, Second Ed. John Burnett.

Human Migration. W.A.V. Clark.

Regional Population Projection Models. Andrei Rogers.

The State of Population Theory: Forward from Malthus. David Colemanand Roger Schofield, eds.

Imagining Tomorrow: History, Technology and the American Future. Joseph C. Corn, ed.

Swidden Agriculture in Indonesia: The Subsistence Strategies of the Kalimantan Kantú. Michael R. Dove.

Glacial Geologic Processes. David Drewry.

Physics of Desertification. Farouk El-Bazand M.H.A. Hassan, eds.

Housing the Homeless. Jon Ericksonand Charles Wilhelm, eds.

Settlement Patterns in Missouri: A Study of Population Origins, with a Wall Map. Russel L. Gerlach.

Desert Development: Man and Technology in Sparselands. Yehuda Gradus, ed.

Nuclear Winter. The Evidence and Risks. Owen Greene, Ian Percivaland Irene Ridge.

The Take-off of Suburbia and the Crisis of the Central City. Günter Heinritzand Elisabeth Lichtenberger, eds.

Regional Input-Output Analysis. Geoffrey J. D. Hewings.

Spatial Transportation Modeling. Christian Werner.

The Atlas of Georgia. Thomas W. Hodlerand Howard A. Schretter, eds.

Latin America. 5th ed. Preston E. Jamesand C.W. Minkel.

Applied Remote Sensing. C.P. Lo.

Localities, Class, and Gender. The Lancaster Regionalism Group.

Urban Social Movements: The City after Castells. Stuart Lowe.

Politics and Method. Doreen Masseyand Richard Meegan, eds.

Land Use. A. S. Mather.

The Kingdom of Coal. Donald L. Millerand Richard E. Sharpless.

The Presidio and Militia on the Northern Frontier of New Spain, A Documentary History, Vol. 1: 1570–1700. Thomas H. Naylorand Charles W. Polzer, S.J., comps. andeds.

Nuclear Power: Siting and Safety. Stan Openshaw.

The Central African Republic: The Continent's Hidden Heart. Thomas O'Toole.

Environmental and Dynamic Geomorphology. Márton Pécsi, ed.

Remote Sensing Principles and Interpretation. Floyd F. Sabins, Jr.

Acid Rain and Friendly Neighbors: The Policy Dispute between Canada and the United States. Jurgen Schmandtand Hilliard Roderick, eds.

Earth's Changing Surface: An Introduction to Geomorphology. M.J. Selby.

International Migration: The Female Experience. Rita J. Simonand Caroline B. Brettell, eds.

On Geography and Its History. D.R. Stoddart.

Transportation Networks: A Quantitative Approach. D. Teodorovic.

Processes in Physical Geography. R.D. Thompson, A.M. Mannion, C.W. Mitchell, M. Parry, J.R.G. Townshend.

Imaging Radar for Resources Surveys. J.W. Trevett.

Dominance and Affection: The Making of Pets. Yi-Fu Tuan.

Capturing the Horizon. The Historical Geography of Transportation since the Transportation Revolution of the Sixteenth Century. James E. Vance, Jr.

Nations at Risk: The Impact of the Computer Revolution. Edward Yourdon.  相似文献   
994.
Several spatial measures of community food access identifying so called “food deserts” have been developed based on geospatial information and commercially-available, secondary data listings of food retail outlets. It is not known how data inaccuracies influence the designation of Census tracts as areas of low access. This study replicated the U.S. Department of Agriculture Economic Research Service (USDA ERS) food desert measure and the Centers for Disease Control and Prevention (CDC) non-healthier food retail tract measure in two secondary data sources (InfoUSA and Dun & Bradstreet) and reference data from an eight-county field census covering 169 Census tracts in South Carolina. For the USDA ERS food deserts measure accuracy statistics for secondary data sources were 94% concordance, 50–65% sensitivity, and 60–64% positive predictive value (PPV). Based on the CDC non-healthier food retail tracts both secondary data demonstrated 88–91% concordance, 80–86% sensitivity and 78–82% PPV. While inaccuracies in secondary data sources used to identify low food access areas may be acceptable for large-scale surveillance, verification with field work is advisable for local community efforts aimed at identifying and improving food access.  相似文献   
995.
996.
Diet-related diseases are a major public health concern, and food environment research explores how built environmental interventions can address nutritional inequalities. Yet other, more direct intervention approaches may also yield positive benefits for residents living in food deserts. This paper presents a case study of a farmers' market move and its effects on healthy food accessibility and customer characteristics in a community with many food deserts. 844 surveys collected in 2011 and 2015 determine customer purchasing patterns and demographics at the Flint (Michigan) Farmers' Market. The market move has meant improved healthy food accessibility for mobility-constrained and low-income residents throughout the region. Counter to past research suggesting that farmers' markets tend to serve higher income groups, socioeconomically disadvantaged people constitute a major consumer demographic at Flint's market. The results of this research have broad utility for communities seeking to ameliorate the challenges of bringing healthy food to isolated food deserts by demonstrating that positioning healthy food in a prominent, central location will attract residents from such neighborhoods while engaging a broad clientele.  相似文献   
997.
Studies of forests in Africa employ the term zone to denote a particular type of forested area. This limited usage speaks to a need for human geographers to pay more attention to elaborating and engaging with the concept of the zone. This article shows why human geography should pay the ‘zone’ more attention. Using Cameroon’s humid forest zone (HFZ) as a case study, the article focuses on how conceptual elaboration of the ‘zone’ can inform analyses of the food product trade in Cameroon. This trade is organized around various types of buyers and sellers (or buyam–sellam in pidgin), and offers a wide variety of wild products to Cameroon’s urban food consumers, including fruits and vegetables, game meat, condiments, medicinal plants, and fibers. Drawing on fieldwork surveys, interviews and focus groups in twenty-four markets of 203 buyam–sellams and 197 of their customers during the wet and dry seasons, this article analyzes narratives about Cameroon’s wild food zone. It ultimately shows what scholarly attention to the ‘zone’ offers in this case that other spatial concepts do not.  相似文献   
998.
Ethical consumption is a vibrant field of research but suffers from both empirical and conceptual biases. Empirically, too much of the data is gathered in the global North, often framing a false binary in which consumption spaces are located in the global North while production takes place in the global South. Conceptually, there is a growing demand for researchers to move away from an emphasis on the individual consumer and instead focus on collective agency and structural change. This paper offers contributions to both of these frontiers of research. It reports on data on ethical consumption and public procurement, collected through the first ever large scale representative survey on procurement criteria and 16 focus groups in Brazil. It concretises these debates by focusing specifically on the pioneering Brazilian school meals policy which supports both “family farms” and organic modes of production at a massive scale, in providing meals to 43 million Brazilian children. Lessons learnt from the study include, firstly, the potential for successfully scaling up ethical consumption through public procurement; secondly, the way in which such scaling-up forces the public debate to engage with food production and consumption at a systemic level; and thirdly, how the systems-level debate leads to a repoliticisation of the discussion of the cultural, social, economic and environmental role of food and farming. The focus group discussions showed a high degree of support for the school meals policy, including from affluent citizens whose children would not benefit from the scheme. Surveys also showed strong support from Brazilian citizens for using environmental and social criteria in public procurement.  相似文献   
999.
沙漠是除南极地区之外的另一陨石样品的主要来源地。我国拥有面积辽阔的沙漠,为陨石的收集提供了有利的地理条件。2013年5月,在首次新疆库姆塔格沙漠陨石考察中,发现并收集到46块陨石样品,确定了3个陨石富集区:Hami、Alatage Mountain(AM)和Kumtag。对其中的10块代表性陨石样品进行了矿物岩石学研究,在此基础上确定了它们的化学群、岩石类型、冲击变质程度和风化程度。10块库姆塔格陨石均为普通球粒陨石,其中1块样品Kumtag014(Fa摩尔百分比为9.1~48.3,相对标准偏差PMD为51.0;Fs摩尔百分比为2.8~30.3,PMD为54.2)属于非平衡型L群。依据橄榄石Fa的PMD将其进一步划分为3.4亚型,属于相当原始的球粒陨石样品。另外9块经历了明显的热变质作用,为5型普通球粒陨石,包括7块L群(Fa22.6~25.9,Fs 17.6~21.4)和2块H群(Fa 18.2~20.8,Fs 16.0~17.8)。这些陨石的冲击变质程度:5块S3型,4块S2型,1块S1型;风化程度:3块W1型,6块W2型,1块W3型。  相似文献   
1000.
Anticipation methods and tools are increasingly used to try to imagine and govern transformations towards more sustainable futures across different policy domains and sectors. But there is a lack of research into the steering effects of anticipation on present-day governance choices, especially in the face of urgently needed sustainability transformations. This paper seeks to understand how different perspectives on anticipatory governance connect to attempts to guide policy and action toward transformative change. We analyze perspectives on anticipatory governance in a global network of food system foresight practitioners (Foresight4Food) – using a workshop, interviews, and a survey as our sources of data. We connect frameworks on anticipatory governance and on transformation to analyse different perspectives on the future and their implications for actions in the present to transform food systems and offer new insights for theory and practice. In the global Foresight4Food network, we find that most foresight practitioners use hybrid approaches to anticipatory governance that combine fundamentally different assumptions about the future. We also find that despite these diverse food futures, anticipation processes predominantly produce recommendations that follow more prediction-oriented forms of strategic planning in order to mitigate future risks. We further demonstrate that much anticipation for transformation uses the language on deep uncertainty and deliberative action without fully taking its consequences on board. Thus, opportunities for transforming future food systems are missed due to these implicit assumptions that dominate the anticipatory governance of food systems. Our combined framework helps researchers and practitioners to be more reflexive of how assumptions about key human systems such as food system futures shape what is prioritized/marginalized and included/excluded in actions to transform such systems.  相似文献   
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