Regional aboveground biomass equations for North American arid and semi-arid forests

Calculations of dry tree, plot and regional aboveground biomass, M, and assessments of complex diverse forests remain key challenges in the implementation of conventional and sustainable projects. This study reports a set of robust regional equations and the application of several allometric tree and plot M equations in Mexican arid and semi-arid forest communities. The data were collected from 1084 tree M fitting models, and 195 arid and semi-arid and 206 mesquite trees and 55 plot datasets were used to validate the models. Theoretical, semi-empirical and empirical models with exogenous variables, as well as wood specific gravity, diameter, top height, and form-factor values, were used to evaluate aboveground biomass. Empirical computer-based equations projected more consistently similar tree M assessments than did semi-empirical or theoretical models. Therefore, empirical models are recommended for assessments of tree and plot M, and future allometry research should properly address independent variables in more theoretical models. The large sample size, model richness, economic and ecological importance, and wide coverage of this dataset make it useful for estimating several biogeochemical and bioenergy density parameters and contribute to the body of knowledge regarding heterogeneity in dry forest stand structures.     

Up Against the Law: Legal Structuring of Political Opportunities in Neighborhood Opposition to Group Home Siting in Massachusetts

Abstract

Conflicts over siting of group homes for people transitioning out of homelessness or struggling with addiction illustrate the multiscalar dynamics at play between locally-based activism and supra-local laws. In Massachusetts, the state-scale legal environment limits the effectiveness of opposition to group housing; nonetheless, such opposition occurs at the municipal level. Drawing on media accounts, official documents, and interviews with stakeholders in conflicts over group home siting in Worcester, Massachusetts, I investigate the dynamics between neighborhood place claims, the responses of the local state, and the state-wide laws governing group home siting. Examining the legal frameworks relevant to social movement grievances demonstrate that law structures the political opportunities available for protest and local government response.     

Financing Flexibility in a Global Market: The Metropolitan Distribution of Equity Investment1

As firms increasingly rely upon intangible assets such as human capital, innovative capacity, and brand equity, they are less able to tap traditional sources of capital such as bank or debt financing. Equity finance (the offering of ownership shares through public stock markets) is frequently the only means of finance available to knowledge-based firms or firms with few fixed assets. The intent of this research is to chart the spatial patterns of equity investment growth in the U.S. metropolitan system using the market capitalizations of 7,926 U.S. firms. Given the necessity of capital for economic growth, these patterns are of obvious importance to geographers. It is shown that volumes of equity investment are both highly skewed towards large firms, the service and FIRE sectors, and a core of metropolitan headquarters sites. Equity capital was found to flow away from Manufacturing Belt cities and towards cities dominated by smaller firms. In addition, it was found that changes in the volume of equity investment in locally headquartered firms is positively correlated to changes in personal income, population, and total employment.     

Sense of Place in Hamilton,Ontario: Empirical Results of a Neighborhood-Based Survey

Although the concept of sense of place has a long history in the social sciences, relatively few studies have attempted a quantitative analysis of sense of place at the neighborhood level. This study reports on the empirical findings of a sense of place survey developed and tested in two contrasting neighborhoods in Hamilton, Ontario, Canada: Southwest Mountain, an upper-middle-class suburban neighborhood and Northeast Industrial, a lower-income, working-class neighborhood located in the heart of the city's industrial district. The principal objective is to assess the relationship between sense of place and the socio-demographic characteristics of residents living in neighborhoods of very different socioeconomic status. This study also introduces a method for calculating a neighborhood sense of place score derived from a fully tested, validated survey instrument. It was found that sense of place was strongest in Southwest Mountain, and among seniors, long-term residents, unmarried people, and immigrants. In addition, residents with a lower level of education and those in the unpaid labor force had a stronger sense of place.     

The Study of Human Action in the Physical Environment

Scientists have been formally studying the consequences of human action at least since Buffon and Humboldt in the 1700s. In 1864, Marsh published Man and Nature, a comprehensive synthesis documenting how people had been transforming Earth. This prominent catalogue of how people disturb Nature's harmonies was updated by Marsh in 1874 and by geographers in 1956 and 1990. Today the leading conceptions of human-environmental interaction are similar to Marsh's theme that people are the disturbers of Nature's harmonies. Effects of human action are considered using conceptions such as direct/indirect, intentional/accidental, and beneficial/detrimental. For a fresh approach, physical geographers could consider action more directly. Human action can be studied as any other process is. Systems concepts and energy flows used to evaluate natural forces can also be used to evaluate human forces. The centennial of the Association of American Geographers is an appropriate time to reflect on how physical geographers have been studying human-environmental interactions and to consider new approaches.     

农村劳动力转移就业环境认知研究体系与方法

根据行为地理学观点,通过农村劳动力转移就业决策过程分析,认为农村劳动力转移就业环境认知,是指农村劳动力面临多样化的就业地和就业环境,对其进行的环境外观感觉以及整体认识和综合解释过程。依据地理认知理论,构建了农村劳动力转移就业环境认知研究体系:基于目标与过程的转移就业环境认知研究;基于个体变量与群体文化因子的转移就业环境认知研究;转移就业环境认知层次(环境特征感知、环境对象认知、环境格局认知)研究。探讨了农村劳动力转移就业环境认知研究的基本方法:民族志方法、定量关系模型、时空路径等。可以预测,农村劳动力转移就业环境认知研究将促进混合研究路径的发展。     

基于文化资源的沿海港口地区创意产业发展研究

如何将港口文化资源禀赋转化为创意产业,促进滨海港口地区复兴是后工业社会全球沿海港口地区发展研究的核心论题。本文探析了文化资源到创意产业的转化潜能、介质、路径、模式和运作机制,并在文化经济地理学视角下架构其实证研究范式,进而以中国舟山普陀区的木帆船、沙雕等创意产业为例,采用文化经济地理学方法调查了创意产品生产过程的项目网络特征。研究发现：港口文化资源转化为创意产业的适宜条件是由创意、资本、管理等要素结网构成创意场域,亦即在市场主导下将文化资源与现代创意、媒介、市场需求等网络式融合。最后提出促推浙江港口地区文化资源发展创意产业可持续发展的建设的建议。     

Space–time opportunities for multiple agents: a constraint‐based approach

Constraint‐based models and models constructing accessibility measures mainly focus on single agents having only one available transport mode. However, numerous cases exist where multiple agents or groups of individuals with different available transport modes want to participate in a joint activity at a certain location. The aim of this paper is to provide new insights into representing and reasoning about feasible space–time opportunities for multiple agents. Relying on concepts of time geography, we propose a conceptual framework in order to determine interaction spaces for groups of individuals. Besides availability of means of transport and the locations of each individual, minimum activity duration and opening hours of opportunities are taken into account. The reasoning about space and time is visualized in three dimensions using a hybrid (CAD/GIS) system.