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1.
Following a strictly theory-building approach, we developed an agent-based simulation model, the Nice Musical Chairs model, to represent the competition between groups of stakeholders of farming and herding activities in the arid Afro-Eurasia. The model deepens the questions raised by the results of our former model, the Musical Chairs model, and further introduces three socio-economic mechanisms, which modulate the behavior and performance of stakeholders and their groups. First, we define land use pairing as the awarding, regarding productivity, of any direct cooperation between farming and herding within a group. Second, group management is modeled as the prerogative of a group leadership to manage stakeholders to pursue a particular proportion between farming and herding. Third, we introduce restricted access to pasture as the engagement in territorial control of rangelands in opposition to an open access regime. An exhaustive exploration of scenarios and parameters placed the control over rangelands as the most significant factor in the formation of land use patterns, followed by land use management. While the effect of land use pairing is mild in comparison, it is still a significant factor in group selection and thus in the persistence of particular land use patterns in the long run.  相似文献   

2.
城市空间扩散增长模型与模拟   总被引:5,自引:0,他引:5  
刘妙龙  陈鹏 《人文地理》2004,19(2):6-11
城市模型模拟是上世纪90年代上半期形成并迅速发展的地学计算理论、方法与应用研究的最重要领域,国外以M. Batty为代表的规划与地理学家们进行了开创性的研究,取得了很多有用成果。本文借鉴这些学者的研究思路,从城市土地利用与开发的视角,利用疾病感染、传播机理的模拟方法,研究城市空间扩展、演化动力学过程的模型模拟问题;为模拟城市土地开发利用在不同阶段的表现与特征,研究了基本模型的不同变换形式;讨论了基于细胞自动机模型的城市空间扩展模型的计算结构,依据模拟结果,探讨了以城市形态扩展特征为指标进行城市分类的可行性,尝试对城市地理学的模型模拟方法作一拓展。  相似文献   

3.
Accessibility is now a common way to measure the benefits provided by transportation–land use systems. Despite its widespread use, few measurement options allow for the comparison of accessibility across multiple urban systems, and most do not adequately control for market competition between demand-side actors and supply-side facilities in localized markets. In this article, we develop a measure of competitive access to destinations that can be used to accurately compare accessibility between regions. This measure stems from spatial interaction modeling and accounts for competition at both the supply and demand sides of analysis, regional differences in transportation networks and travel behavior, and any imbalance between the size of the population and the number of opportunities. We use this method to compute access to employment for Canada's eight largest cities to comparatively examine inequalities in accessibility, both within and between cities, and by travel mode.  相似文献   

4.
The advent of new techniques of dental ageing has permitted inferences about the age-structures of ancient animal populations on the basis of faunal remains. Unfortunately, inference from archaeological populations of faunal elements to the age-structure of ancient herds is fraught with both sampling problems and logical difficulties. The relationship between a living herd—a dynamic system characterized by growth—and a static archaeological population is more complex than that assumed by current models based on kill-off patterns and survivorship curves. Using a computer simulation, these logical relationships are explored, and the effects of herd growth on the composition of live and death populations are evaluated. By employing the simulation within a deductive framework, constrained by ethnographically derived criteria for reproduction, mortality, and economic viability in the Near East, it is possible to determine whether certain archaeological kill-off patterns could represent viable herding systems. Examples were found to vary widely in terms of both demographic plausibility and economic viability. Some implications for the possible course of ova-caprine domestication in the Near East are discussed.  相似文献   

5.
This article presents a new analytical framework for studying cities in the developing world based on the ‘political settlements’ approach. This has a dual purpose: to enrich comparative urban research by bringing new theoretical ideas to bear on this field, but also to use capital cities as a lens to better understand national political settlements. The central argument is that urban built environments and their transformations in situations of late development reflect the workings of different varieties of clientelism, and by analysing the former we can better understand the latter. Specifically, issues such as the nature of urban land use and land allocation, the pace and form of construction, the effectiveness of environmental regulation and the provision of housing for different income groups are all revealing of political settlements and their broader development implications. The potential of this approach is explored through three narrative ‘sketches’ of contemporary urban development in Eastern Africa: the ‘city as marketplace’ (Kampala), the ‘city as expo’ (Kigali) and the ‘city as construction site’ (Addis Ababa). In presenting this framework, the article seeks to advance debate on epistemological and analytical approaches to the study of both power relations and differential patterns of urban development.  相似文献   

6.
With the dismantling of herding collectives in Mongolia in 1992, formal regulatory institutions for allocating pasture vanished, and weakened customary institutions were unable effectively to fill the void. Increasing poverty and wealth differentiation in the herding sector, a wave of urban–rural migration, and the lack of formal or strong informal regulation led to a downward spiral of unsustainable grazing practices. In 1994, Mongolia's parliament passed the Land Law, which authorized land possession contracts (leases) over pastoral resources such as campsites and pastures. Implementation of leasing provisions began in 1998. This article examines the implications of the Law's implementation at the local level, based on interviews with herders and officials in all levels of government, and a resurvey of herding households. Amongst many findings, the research shows that poorer herders were largely overlooked in the allocation of campsite leases; that the poor had become more mobile and the wealthy more sedentary; that there had been a sharp decline in trespassing following lease implementation, but that many herders and officials expected pasture leasing to lead to increased conflict over pastures. The Land Law provides broad regulatory latitude and flexibility to local authorities, but the Law's lack of clarity and poor understanding of its provisions by herders and local officials limit its utility. The existing legal framework and local attitudes stand in clear opposition to the implied goal of land registration and titling — an all‐embracing land market and the supremacy of private property rights.  相似文献   

7.
This paper presents an agent-based model of shifting cultivation that explains patterns of land use and forest structure beyond the extensive margin of agriculture. The anthropological literature is first examined in order to specify key aspects of farming group preferences vis-a-vis food requirements. Two existing theories of shifting cultivation are then addressed to motivate the present formulation, which integrates household production theory and the concept of optimal rotation originating in the forestry literature. It is argued that the cycling of secondary vegetation by shifting cultivators represents a form of rotation analogous to the foresters' case. The model developed explains the empirical observation that individual agents use multiple rotation ages, and it does so for the nonmarket case, which is consistent with the institutional environment of many indigenous peoples and colonists. The paper concludes with an application to the problem of rural violence in Brazil and with suggestions for extending the framework to the policy arena of global change.  相似文献   

8.
We argue for short‐distance transhumance as a system of livestock mobility in ancient Arkadia, as well as in many other parts of ancient Greece. This model is a sustainable system of animal husbandry that resolves the technical and political issues posed by long‐distance transhumance and provides a historical interpretation of ancient Arkadian economies using a household herding model. Moreover, it helps us to integrate economy and socio‐political identity in mountainous areas. For this reason, we argue that it is necessary to revamp the traditional model for understanding ancient Greek husbandry, which is based on the opposition between astu and chora. This model has contributed greatly to fostering an image of ancient Arkadia as a territory especially dedicated to pastoralism, with the possible presence of long‐distance transhumance. However, archaeological, environmental and historical studies call into question the traditional models and point to other interpretations.  相似文献   

9.
Spatial land‐use models over large geographic areas and at fine spatial resolutions face the challenges of spatial heterogeneity, model predictability, data quality, and of the ensuing uncertainty. We propose an improved neural network model, ART‐Probability‐Map (ART‐P‐MAP), tailored to address these issues in the context of spatial modeling of land‐use change. First, it adaptively forms its own network structure to account for spatial heterogeneity. Second, it explicitly infers posterior probabilities of land conversion that facilitates the quantification of prediction uncertainty. Extensive calibration under various test settings is conducted on the proposed model to optimize its utility in seeking useful information within a spatially heterogeneous environment. The calibration strategy involves building a bagging ensemble for training and stratified sampling with varying category proportions for experimentation. Through a temporal validation approach, we examine models’ performance within a systematic assessment framework consisting of global metrics and cell‐level uncertainty measurement. Compared with two baselines, ART‐P‐MAP achieves consistently good and stable performance across experiments and exhibits superior capability to handle the spatial heterogeneity and uncertainty involved in the land‐use change problem. Finally, we conclude that, as a general probabilistic regression model, ART‐P‐MAP is applicable to a broad range of land‐use change modeling approaches, which deserves future research.  相似文献   

10.
An Evolutionary New Economic Geography Model   总被引:3,自引:0,他引:3  
In this paper we present a general new economic geography model with multiple industries and regions, full labor and capital mobility, land use in production and consumption, and a dynamic adjustment process in which consumers maximize utility and firms respond to nonzero profits. All industries use intermediate inputs as well as land, labor, and capital. Systems of cities form endogenously within this framework, including asymmetrical urban hierarchies and cities of different sizes and industry compositions. Each urban area has a bid-rent gradient and zones with land uses and densities as in the von Thünen model. The equilibrium depends not only on initial conditions but also on speeds of adjustment. The model is a prototype for empirical implementation, as illustrated with a simulation of the effects of transportation cost reductions.  相似文献   

11.
We evaluate local versus distant land‐use models at Neolithic Çatalhöyük, central Anatolia, using strontium isotope analysis of sheep tooth enamel and charred plant remains. Interpretation of strontium in sheep tooth sequences is constrained by previous oxygen isotope work, which largely excludes summer movement to the mountains but cannot distinguish between herding on the plain and the closest upland‐zone, Neogene limestone terraces. We establish a baseline contrast in modern plant strontium values between the plain and terraces and infer predominant herding on the plain from seven sheep tooth sequences. Archaeobotanical plant strontium values exclude the use of the terraces for cultivation and foraging. Relatively local crop and sheep management, plausibly intensive and integrated to some degree, given limited dry ground, appears likely on the basis of this pilot study.  相似文献   

12.
The semi‐arid zone of Southwest Asia, known as the Fertile Crescent, is under unprecedented stress because of agricultural development. Where rain‐fed agriculture and transhumant herding had prevailed over ten millennia, today intensive cultivation with irrigation threatens future sustainability. A number of interconnected, but uncoordinated drivers of change combine to shape the landscape and its future, and their changes make it hard to anticipate future requirements and opportunities, as well as to implement policies, whether by local stakeholders or at the national level. Among the factors that comprise the socio‐natural systems are (1) climate, (2) water and soil resources, (3) history of land use, (4) social, economic and political factors, (5) infrastructural developments (6) interstate impacts, and (7) legacies of the past. The example of the Khabur River drainage in northeastern Syria shows the dynamic interplay among these factors over the past 70 years, with implications for the way future policies and practices are developed.  相似文献   

13.
Abstract

This article argues that the existing network of roads, arising from socially mediated human behavior, represents a well-preserved feature present across a broad region and contains latent historical information that can be retrieved using appropriate analytical techniques. It presents a method combining iterative cost path modeling and proximity analysis to reconstruct patterns of historical movement, and uses the results of this analysis as a heuristic tool to delineate regional social distinctions evident in characteristics of land appropriation and settlement within an area on the peripheries of the goldfields of central Victoria. The results of the least-cost route and proximity analysis presented in this paper delineate variations in patterns of movement across the study area that suggest distinctions in community development and character, adding depth and nuance to histories of the gold fields and their later years and supporting alternatives to assumptions of linear historical change.  相似文献   

14.
This article presents a survey of Neolithic economy, land use, trade, natural environment, and usage of plant and animal resources in central Europe, 5415–2240 B.C. (4500–1800 bc). Early, Middle A and B and Late Neolithic materials are summarized and compared. The earliest farmers expanded from southern Hungary and adjacent areas into central Europe over a relatively short time period, 100–200 years. They occupied areas only with good soils; thus probably hunters and gatherers continued to exist in many regions of central Europe. There is an increase in population and more upland areas are exploited for farming during the Middle Neolithic A and B periods. By the Middle Neolithic B period, low-level hierarchical or ranked societies appear in some regions of central Europe. The Late Neolithic may represent a modification of the mixed farming strategy observed during the earlier periods. Perhaps the herding of domestic animals became more important.  相似文献   

15.
What can professional land managers gain by consulting with local communities? Scientific knowledge provides valuable insights into the causes of environmental change and the processes by which it occurs but often lacks a historical dimension. Recollections of local people can supplement both historical records and scientific understandings of cause and process to achieve a more comprehensive picture of change over time. However, the process of memory is tied to life experience and is highly selective. Any attempt to use oral accounts in constructing a picture of environmental change over time must also include an analysis of the process of memory itself. Drawing on oral histories with long term residents of the Tumut region of NSW, this paper explores the nature of local environmental knowledge and evaluates oral history as a source of information for understanding environmental history and the impact of changing patterns of land use.  相似文献   

16.
清代以来西辽河流域人地关系的演变   总被引:5,自引:0,他引:5  
本文考察了清代以来 30 0余年间西辽河流域行政格局、人口、土地利用、动植物等人地关系要素的变化 ,并得出四个主要结论 :1行政交错格局的变化使流域农业人口增加并确立了以农业为主的生产方式 ;2清代以来政府实行的移民开垦政策是流域人地关系恶化的主导因素 ;3牧民游牧生活方式的转变是流域人地关系恶化的重要因素 ;4气候和土壤条件是区域农业开发后流域人地关系加速恶化的基本因素。  相似文献   

17.
The objective of this paper is to address the question of open space preservation in an urbanization context. We study the possibility of preserving two different types of open spaces, namely, large open spaces at cities’ outskirts and small intraurban open spaces. Thus, we contribute to the debate of land sharing versus land sparing in an urban context. We analyze these questions by way of a theoretical microeconomic framework that takes into account both households’ preferences for open space and regulators’ interest in the preservation of natural habitat for biodiversity. We compare land use patterns at private equilibrium and when the social planner maximizes social welfare.  相似文献   

18.
A Generalized Model for Cellular Urban Dynamics   总被引:1,自引:0,他引:1  
  相似文献   

19.
Studies of historical change in cultivated land use in Northeast China have become important in the discussion of food supply safety and the reconstruction of land use/cover changes in China. This paper subjects a number of sources relating to land use change in the three provinces of Northeast China to comparative analysis. The data examined include Russian survey data (1914), data from local and regional Chinese governments during the Republic of China (1931), data from the Japanese Society of Manchuria Railway (SMR) for 1940 and various sets of contemporary Chinese data for the second half of the 20th century. A unified method of reconstructing the data and estimating the rate of cultivated land use change in Northeast China during the 20th century is developed here. A relational model is proposed for this purpose. It establishes a general framework for relating the various sets of data generated in different time periods and indicates ways in which the data have to be calibrated to ensure their comparability. The calibration of the data involves correlation and regression analysis. The results of the comparative analysis show that the area of and rate of change in cultivated land use in Northeast China increased until the last decade of the twentieth century. Increase rates were particularly high between 1914–1931 and 1950–1960.  相似文献   

20.
This paper formulates a multiple discrete‐continuous probit (MDCP) land use model within a spatially explicit economic structural framework for land use change decisions. The spatial MDCP model is capable of predicting both the type and intensity of urban development patterns over large geographic areas, while also explicitly acknowledging geographic proximity‐based spatial dependencies in these patterns. At a methodological level, the paper focuses on specifying and estimating a spatial MDCP model that allows the dependent variable to exist in multiple discrete states with an intensity associated with each discrete state. The formulation also accommodates spatial dependencies, as well as spatial heterogeneity and heteroskedasticity, in the dependent variable, and should be applicable in a wide variety of fields where social and spatial dependencies between decision agents (or observation units) lead to spillover effects in multiple discrete‐continuous choices (or states). A simulation exercise is undertaken to evaluate the ability of the proposed maximum approximate composite marginal likelihood (MACML) approach to recover parameters from a cross‐sectional spatial MDCP model. The results show that the MACML approach does well in recovering parameters. An empirical demonstration of the approach is undertaken using the city of Austin parcel level land use data.  相似文献   

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