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1.
Cropland displacement, as an important characteristic of cropland change, places more emphasis on changes in spatial location than on quantity. The effects of cropland displacement on global and regional food production are of general concern in the context of urban expansion. Few studies have explored scale-effects, however, where cropland is displaced not only within, but also outside, the administrative boundary of a certain region. This study used a spatially explicit model (LANDSCAPE) to simulate the potential cropland displacement caused by urban land expansion from 2020 to 2040 at four scales of the Chinese administration system (national, provincial, municipal, and county levels). The corresponding changes in potential cereal production were then assessed by combining cereal productivity data. The results show that 4700 km2 of cropland will be occupied by urban expansion by 2040, and the same amount of cropland will be supplemented by forest, grassland, wetland, and unused land. The potential loss of cropland will result in the loss of 3.838×106 tons of cereal production, and the additional cropland will bring 3.546×106 tons, 3.831×106 tons, 3.836×106 tons, and 3.528×106 tons of potential cereal production in SN (national scale), SP (provincial scale), SM (municipal scale), and SC (county scale), respectively. Both SN and SC are observed to make a huge difference in cereal productivity between the lost and the supplemented cropland. We suggest that China should focus on the spatial allocation of cropland during large-scale displacement, especially at the national level.  相似文献   

2.
Du  Yunyan  Tu  Wenna  Liang  Fuyuan  Yi  Jiawei 《地理学报(英文版)》2021,31(2):179-194
Mobile internet and wireless communication technologies have produced unprecedented location-aware data. Such big geospatial data can be used as a proxy measure of the ‘digital footprints' left by us on the planet and provide a valuable opportunity to understand the dynamic and short-term human disturbance on the nature at fine scales. This study investigated the spatiotemporal variations of human's digital footprints on the Qinghai-Tibet Plateau using smartphone-users-generated Tencent's location request data. The results showed that human's digital footprints cover less than 5% of Qinghai and Tibet, exhibiting either a U-shaped or an N-shaped temporal change pattern during the major festivals. Spatial changes of the digital footprints manifested a transition process from dispersion to concentration in Xining and Lhasa. Human disturbance assessment of seven large nature reserves on the plateau showed that the Qinghai Lake is the most disturbed one as shown by 14.6% of its area is stained with human digital footprints and the areal average of footprint intensity is 1.59, and the disturbance was significantly escalated during the National Day holiday. By contrast, the Qangtang and Hoh Xil are the least affected nature reserves with the two indices less than 1% and 0.1, respectively.  相似文献   

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China’s rapid urbanization has created large scale of population migration, resulting in many villages being dominated by “left-behind” women, and weak governance of those collectively owned resources. The situation has required these women to take up the functions of decision-making and governance as a remedial mechanism as well as a new path. Based on a case study in a typical hollowing-out village in central China, this paper explores an example of left-behind women’s collective action to prevent the over-exploitation of community and resources. It finds out that although traditionally excluded from public activities and marginalized, the “left-behind” women were able to mobilize and enhance collective action. When empowered, they are growing fast with endurance and courage, and as capable as anyone of defending the common-pool resources. It suggests that the left-behind women offer a new governance option for those population hollowing out rural areas.  相似文献   

5.
The objective of this study was to explore the mechanism through which a reform in environmental education (EE) programs affects pupils’ relation to the environment. We surveyed 589 pupils aged 9–12 years in three types of Israeli elementary school: regular schools, schools that implement an EE program (designated “green schools”), and schools that implement a more intensive EE program (designated “persistent green schools”). Analyzing the results obtained from our questionnaire, we found that both EE programs had a positive effect on environmental attitudes. Importantly, however, only persistent green schools showed a direct positive effect on environmental behavior. In addition, we assessed the influences of various demographic and other factors on pupils’ relation to the environment. Of note, we found that students who spent their leisure time watching TV or engaging with other electronic media expressed less concern about the environment.  相似文献   

6.
“Honest broker” refers to scientists facilitating complex political decisions from a neutral position, aiming to expand the scope of choice available instead of advocating a certain policy. This article reflects on the experiences of three scientists acting as honest brokers while carrying out a multicriteria evaluation to help politicians choose the water supply option for the city of Oulu, Finland. The process was considered successful and many politicians said that they have never before been that well informed when making a decision. The case primarily shows that besides the common knowledge brokerage roles targeting knowledge exchange, the honest brokerage approach relates more to managing social relationships and balancing political games and rapidly evolving discussions. Trustful relationships increased the perceived credibility of the brokers and ensured two-way communication. On the other hand, the brokers faced ethical dilemmas and difficulties of staying impartial while finding out confidential information related to political strategies.  相似文献   

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This paper sets out to evaluate the freedom of voice for Peruvian stakeholders affected by hydrocarbon development. This occurs through the utilization of a political ecology of voice (PEV) theoretical framework based upon the theory of voice by Albert Hirschman and political ecology. PEV can be defined as the study of economic, political, social, and geographical factors over a specific time period and their impact upon the use of voice by stakeholders. Peru’s case study was focused on its main oil-producing Loreto Region and incorporated evaluation of hydrocarbon voice mechanisms (prior consultation and environmental impact assessments) supported by interview testimony of stakeholders and state officials. PEV analysis reveals a political environment which is dangerous, inflexible, and intolerant of Peruvian stakeholders voicing over hydrocarbon development. This is due to the state’s zealous pursuit of its “selva (rainforest) hydrocarbon and development vision” which severely undermines Peruvian stakeholder’s freedom of voice.  相似文献   

9.
Zhang  Ting  Shen  Shi  Cheng  Changxiu 《地理学报(英文版)》2019,29(9):1491-1506
Journal of Geographical Sciences - Analyses of the soil moisture evolution trend and the influence of different types of radiation on soil moisture are of great significance to the simulation and...  相似文献   

10.
Society’s understanding of a conflict is mediated by information provided in mass media, for which researchers stress the importance of analyzing media portrays of stakeholders in a conflict. We analyze information from the Bolivian press regarding the construction of a road crossing the Isiboro-Sécure Indigenous Territory and National Park (TIPNIS). Using stakeholder’s and social network analyses, we explore stakeholder’s positions and alliances as represented in the media and contrast it with previous scholarly work. We found that some actors cited as central in scholar analyses of the conflict are largely absent in the media (e.g., private investors, conservationist sector) and that the media tend to present stakeholders as having more homogeneous positions than the academic literature does while also neglecting some important alliances in their account. The media also suggests that Indigenous communities are forging stronger alliances with urban sectors and civil society, alliances not stressed by researchers.  相似文献   

11.
Construction of dams affects the livelihoods of the population living along the dammed river. There is a need for more studies to guide dam development policies and management to safeguard the livelihoods of local river users. This paper examines the effects of dams on the socio-economic livelihoods of downstream communities by drawing on the Kpong Dam in Ghana constructed from 1979 to 1982 with the goal of supplying energy and for irrigation purposes. Primary data were collected in resettled and non-resettled downstream communities using a mixed-research approach. This case study highlights how the Kpong Dam has affected the downstream river-dependent population whose livelihoods, particularly farming and fishing revolved around the seasonal flow regimes of the Volta River. Our study challenges the general perception that dams increase agricultural production by illustrating that developing ancillary facilities such as irrigation schemes as part of dam projects can enhance all-year-round agricultural production to improve food and income security of downstream households only when constraints such as lack of farm inputs are addressed. To safeguard livelihoods and limit the social impacts of dams, compensation schemes and alternative livelihood activities should be designed to include resettled and non-resettled communities along the downstream areas affected by dam projects.  相似文献   

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A growing number of commentators are forecasting a near-term peak and subsequent terminal decline in the global production of conventional oil as a result of the physical depletion of the resource. These forecasts frequently rely on the estimates of the ultimately recoverable resources (URR) of different regions, obtained through the use of curve-fitting to historical trends in discovery or production. Curve-fitting was originally pioneered by M. King Hubbert in the context of an earlier debate about the future of the US oil production. However, despite their widespread use, curve-fitting techniques remain the subject of considerable controversy. This article classifies and explains these techniques and identifies both their relative suitability in different circumstances and the level of confidence that may be placed in their results. This article discusses the interpretation and importance of the URR estimates, indicates the relationship between curve fitting and other methods of estimating the URR and classifies the techniques into three groups. It then investigates each group in turn, indicating their historical origins, contemporary application and major strengths and weaknesses. The article then uses illustrative data from a number of oil-producing regions to assess whether these techniques produce consistent results as well as highlight some of the statistical issues raised and suggesting how they may be addressed. The article concludes that the applicability of curve-fitting techniques is more limited than adherents claim and that the confidence bounds on the results are wider than usually assumed.  相似文献   

14.
In 2013, we celebrate the 50th anniversary of the publication of V. B. Sochava’s first paper in which he offered the definition of the term “geosystem”. His paper entitled “The definition of some notions and terms in physical geography” remains one of the most frequently cited articles in the national geographical literature. The concept of the geosystem was included in encyclopedias. The geosystem ideology is used in training of specialists in the field of geography.  相似文献   

15.
The underexplored deep Argentine continental margin may be a prospective area for hydrocarbon resources. This study quantifies the degree of certainty about a fundamental part in a petroleum system, the presence of source rocks. Probability theory and, in particular, Bayesian networks provide powerful assessment tools based on incomplete knowledge. However, they should not be applied uncritically in cases where necessary assumptions like independence are not fulfilled or prior probabilities are not known. We discuss the difference between a low probability and the ignorance of a hypothesis, and apply an alternative method to the assessment of source rock presence. The results of this probabilistic argumentation system coincide with the intuitive judgement, stating that there is a quantifiable evidence for a source rock, but no evidence against it.  相似文献   

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This article examines household-level characteristics that predict water insecurity in low-income rural and periurban communities on the Texas–Mexico border. We employ two logistic regression models (binary and ordered) to identify household characteristics that are more likely to result in water insecurity. Our analyses yielded unexpected findings: Whereas socioeconomic factors are weak predictors, immigration status of household members is a significant variable that contributes to household water insecurity. Policymakers need to pay more attention to marginalized communities as “universal” water access still leaves populations without adequate, reliable, and affordable water in the Global North.  相似文献   

18.
Li and Zhang (2012b Li, W. and Zhang, C. 2012b. Comments on ‘Combining spatial transition probabilities for stochastic simulation of categorical fields’ with communications on some issues related to Markov chain geostatistics. International Journal of Geographical Information Science, 26(10): 17251739. [Taylor & Francis Online] [Google Scholar], Comments on ‘Combining spatial transition probabilities for stochastic simulation of categorical fields’ with communications on some issues related to Markov chain geostatics) raised a series of comments on our recent paper (Cao, G., Kyriakidis, P.C., and Goodchild, M.F., 2011 Cao, G., Kyriakidis, P.C. and Goodchild, M.F. 2011. Combining spatial transition probabilities for stochastic simulation of categorical fields. International Journal of Geographical Information Science, 25(11): 17731791. [Taylor & Francis Online], [Web of Science ®] [Google Scholar]. Combining spatial transition probabilities for stochastic simulation of categorical fields. International Journal of Geographical Information Science, 25 (11), 1773–1791), which include a notation error in the model equation provided for the Markov chain random field (MCRF) or spatial Markov chain model (SMC), originally proposed by Li (2007b Li, W. 2007b. Markov chain random fields for estimation of categorical variables. Mathematical Geology, 39(3): 321335. [Crossref] [Google Scholar], Markov chain random fields for estimation of categorical variables. Mathematical Geology, 39 (3), 321–335), and followed by Allard et al. (2011 Allard, D., D'Or, D. and Froideveaux, R. 2011. An efficient maximum entropy approach for categorical variable prediction. European Journal of Soil Science, 62: 381393. [Crossref], [Web of Science ®] [Google Scholar], An efficient maximum entropy approach for categorical variable prediction. European Journal of Soil Science, 62, 381–393) about the misinterpretation of MCRF (or SMC) as a simplified form of the Bayesian maximum entropy (BME)-based approach, the so-called Markovian-type categorical prediction (MCP) (Allard, D., D'Or, D., and Froideveaux, R., 2009 Allard, D., D'Or, D. and Froidevaux, R. 2009. Estimating and simulating spatial categorical data using an efficient maximum entropy approach, Avignon: Unité Biostatistique et Processus Spatiaux Institut National de la Recherche Agronomique. Technical Report No. 37 [Google Scholar]. Estimating and simulating spatial categorical data using an efficient maximum entropy approach. Avignon: Unite Biostatisque et Processus Spatiaux Institute National de la Recherche Agronomique. Technical Report No. 37; Allard, D., D'Or, D., and Froideveaux, R., 2011 Allard, D., D'Or, D. and Froideveaux, R. 2011. An efficient maximum entropy approach for categorical variable prediction. European Journal of Soil Science, 62: 381393. [Crossref], [Web of Science ®] [Google Scholar]. An efficient maximum entropy approach for categorical variable prediction. European Journal of Soil Science, 62, 381–393). Li and Zhang (2012b Li, W. and Zhang, C. 2012b. Comments on ‘Combining spatial transition probabilities for stochastic simulation of categorical fields’ with communications on some issues related to Markov chain geostatistics. International Journal of Geographical Information Science, 26(10): 17251739. [Taylor & Francis Online] [Google Scholar], Comments on ‘Combining spatial transition probabilities for stochastic simulation of categorial fields’ with communication on some issues related to Markov chain geostatistics. International Journal of Geographical Information Science) also raised concerns regarding several statements Cao et al. (2011 Cao, G., Kyriakidis, P.C. and Goodchild, M.F. 2011. Combining spatial transition probabilities for stochastic simulation of categorical fields. International Journal of Geographical Information Science, 25(11): 17731791. [Taylor & Francis Online], [Web of Science ®] [Google Scholar], Combining spatial transition probabilities for stochastic simulation of categorical fields. International Journal of Geographical Information Science, 25 (11), 1773–1791) had made, which mainly include connections between permanence of ratios and conditional independence, connections between MCRF and Bayesian networks and transiograms as spatial continuity measures. In this response, all of the comments and concerns will be addressed, while also communicating with Li and other colleagues on general topics in Markov chain geostatistics.  相似文献   

19.
The “Hu Line” has been regarded as one of the greatest geographical discoveries in China because it reveals the significant spatial relationship between human activity and natural environment. The spatial evolution of population on both sides of the “Hu Line” has had important implications for both urbanization and regional development and has attracted widespread attention during the dramatic economic and social changes since the implementation of reform and opening-up policy in China in 1978. Using Geographical Information System (GIS) techniques, this paper studied the stability of the “Hu Line” and the spatial patterns of population growth on each side by constructing a spatial database of China’s census data from 1982 to 2010. The findings are as follows: (1) In the last 30 years, the “Hu Line” has remained relatively stable, but a new tendency of population change has begun to emerge. The population ratio either side, namely, the southeast half (SEH) and the northwest half (NWH), of the “Hu Line” remains at roughly 94:6 (SHE: NWH). Noteworthy, the proportion of population in the SEH of the “Hu Line” has been decreasing slightly, while that in the NWH has been increasing slightly, as the latter has benefited from its higher rate of natural population growth. (2) The spatial patterns of population growth on both sides of the “Hu Line” were quite different. The degree of population concentration in the SEH increased faster than the NWH. Regions with a negative population growth rate have rapidly expanded; these were mainly located in the south of the “Qinling Mountains-Huaihe River belt” and northeastern China. Meanwhile, regions with a fast population growth rate were mainly concentrated in the Yangtze River Delta, the Pearl River Delta, and the Beijing-Tianjin metropolitan area. Thus, the spatial pattern of population growth in the SEH presented a concentration pattern that could be called “Matthew effect pattern”. (3) The spatial pattern of population growth in the NWH could be regarded as the “Relative Balance pattern.” In the NWH, the population growth rate was positive and the degree of population concentration was very low. There were many minority populations located in the NWH that usually lived in a dispersed pattern but had a higher rate of natural population growth due to the preferential population policy. There were also some regions with a negative rate of population growth in the NWH, which were mainly located close to the “Hu Line” and the Ancient Silk Road. (4) In the future, the spatial patterns of population growth on both sides of the “Hu Line” may continue to evolve. For the SEH, the capacity to attract more people to small and medium-sized cities and towns should be enhanced. For the NWH, the emphasis should be placed on promoting urbanization and enhancing population agglomeration in its major cities.  相似文献   

20.
This study investigates whether social learning among large-scale farmers in central Sweden leads to better natural resource management in the agricultural landscape. Three different frames of social learning are first identified: social learning as a fundamental social phenomenon, social learning as collaborative learning, and social learning as deeper learning. This article investigates the role of social learning and other factors through semistructured in-depth interviews. Results show that learning among farmers is inherently social, but that this learning does not necessarily improve natural resource management or lead to better environmental governance. The article discusses when social learning can be expected to influence natural resources management, and finds that without the presence of policy, individual leadership, or facilitation, it is not an important factor. Furthermore, the call for social learning based on results from successful instrumental application risks obscuring findings indicating that both social learning and better natural resource management are conditioned on the same external factors.  相似文献   

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