Facilitating resilient rural-to-urban sustainable agriculture and rural communities

ABSTRACT

This article contributes to efforts to validate a common set of parameters and principles of sustainable agriculture. Comparisons between alternative forms of sustainable agriculture and rural-to-urban community resilience are investigated. Conclusions are drawn between multiple sustainable/alternative agriculture systems and evaluated. A set of common baseline parameters and principles is proposed as a method of evolving a common structural framework for strengthening sustainability of agriculture and rural contexts. Concepts of rural-to-urban community sustainability are proposed, supporting sustainable agriculture contexts as rural and urban. In the twenty-first century, agriculture is becoming more diversified and less typified as a rural occupation. Urban agriculture is expanding as the need for fresh, affordable, accessible agriculture produce increases in urban areas. Evidence supports symbiotic relationships between sustainable agriculture and rural/urban communities, although some claim this relationship has not been clearly defined.

This article investigates sustainable agriculture from two perspectives. We ask ‘what are common parameters and principles of the various forms of sustainable agriculture,’ and ‘why urban-to-rural context.’ Organic agriculture parameters and principles are proposed as a conceptual framework toward establishing baseline parameters and principles for sustainable agriculture. Best management parameters of urban and rural sustainable agriculture in the United States and the United Kingdom are examined for their potential to develop a strengthening framework of parameters and principles of agriculture and rural-to-urban sustainability. These results are compared and evaluated for their effectiveness in redefining current sustainable agriculture practices, and their value in strengthening sustainable agriculture symbiosis with rural-to-urban community systems.     

The specification of sustainable urban transport strategies

Transport strategies have been developed for nine European cities to achieve optimum performance in terms of a range of objective functions. The functions selected represent economic efficiency, sustainability and a combination of these. The strategies have been based on combinations of a standard set of policy instruments, including public transport infrastructure, frequency and fares, road capacity increases, low cost road pricing and parking charges. The optimisation method is described, and results presented. The reactions of city authorities to the proposed strategies are discussed and implications for transport policy outlined.     

工业绿色发展评价指标体系及应用于广东省区域评价的分析

工业的快速发展,给资源环境带来了前所未有的压力,于是人们纷纷探讨绿色发展之路.工业绿色发展评价指标体系的研究旨在发现工业绿色转型升级中的薄弱环节,设计评估工业的绿色发展状况的指标,引导工业绿色转型升级,从而实现工业发展与资源环境的和谐统一.文章借鉴脱钩理论的核心理念,分析资源环境的特征指标,利用工业资源消耗或污染物排放变化对工业产值的弹性脱钩值作为考察工业绿色转型升级的动态指标,建立包括工业资源环境压力、工业资源环境弹性脱钩和工业发展绿化度3个方面的工业绿色发展评价指标体系,并应用于广东省21个地级以上城市的评价分析.研究表明,该指标体系对于评价工业绿色发展具有实际可操作性,结果合理、可靠.对广东各地的实证评价分析显示,广东省工业总体绿色发展水平不断提升,在高压力水平下,逐步向资源节约型、环境友好型的新型工业化道路转型.但由于各地工业发展水平不同、资源环境约束目标不同,工业绿色发展的进程也存在较大区域差异.资源环境约束严格的珠三角核心区工业绿色发展情况相对其他地区较好,属高绿化度高资源环境压力的绿色发展模式.资源环境约束较严格的粤北山区工业转型升级也有明显进展.而在资源环境约束管理不大的珠三角非核心区与粤西地区中,江门和湛江工业绿色发展相对较好,肇庆和茂名一般,惠州和阳江工业呈粗放发展,粤东地区除汕头外,工业粗放发展趋势明显.因此,各地应制定针对性措施,促进工业结构调整,限制高消耗、重污染型行业发展,加大工业污染防治力度,推进高消耗、重污染型行业的生态化转型,推动工业绿色转型升级加快.     

复合型抑尘剂的制备研究

配制的复合型抑尘剂是甲基丙烯酸甲酯-丙烯酸丁酯共聚物乳液。采用正交法构造四因素三水平设计正交实验,用预乳化法合成抑尘剂。对数据直观分析,得出在乳化剂质量分数为2%,引发剂质量分数为1.1%,交联剂质量分数为2%,搅拌强度为100 r/min的实验条件下,抑尘剂性能较好。抑尘剂应用性能测试表明:抑尘剂具有较好的吸水保水性,配制的复合型抑尘剂具有较好的经济效益和社会效益,应用前景广阔。     

Correlates of bushmeat hunting among remote rural households in Gabon, Central Africa

Hunted wild animals (i.e., bushmeat) are a main source of protein for many rural populations in the tropics, and the unsustainable harvest of these animals puts both human food security and ecosystem functioning at risk. To understand the correlates of bushmeat consumption, we surveyed 1219 households in 121 rural villages near three newly established national parks in Gabon. Through the surveys we gathered information on bushmeat consumption, income, and material assests. In addition, we quantified land cover in a 5-km radius around the village center and distance of the village center to the nearest park boundary. Bushmeat was not a source of income for most households, but it was the primary animal protein consumed. Ninety-seven percent of households consumed bushmeat at least once during a survey period of 12 days. Income or wealth, land cover, distance of village to the nearest park boundary, and level of education of the head of the household were among the factors that significantly related to the likelihood of consuming any of the 10 most commonly consumed species of bushmeat. Household size was the predictor most strongly associated with quantities of bushmeat consumed and was negatively related to consumption. Total bushmeat consumption per adult male equivalent increased as household wealth increased and decreased as distance of villages to park boundaries increased. Bushmeat consumption at the household level was not related to unit values (i.e., price estimates for a good that typically does not have a market value; estimates derived from willingness to sell or trade the good for items of known price) of bushmeat or the price of chicken and fish as potential substitutes. The median consumption of bushmeat at the village level, however, was negatively related to village mean unit values of bushmeat across all species. Our results suggest that a lack of alternative protein sources motivated even the wealthiest among surveyed households to consume bushmeat. Providing affordable, alternative protein sources to all households would likely reduce unsustainable levels of bushmeat consumption in rural Gabon.     

Assessing citizen contributions to butterfly monitoring in two large cities

Citizen science may be especially effective in urban landscapes due to the large pool of potential volunteers. However, there have been few evaluations of the contributions of citizen scientists to knowledge of biological communities in and around cities. To assess the effectiveness of citizen scientists' monitoring of species in urban areas, we compared butterfly data collected over 10 years in Chicago, Illinois (U.S.A.), and New York City, New York (U.S.A.). The dates, locations, and methods of data collection in Chicago were standardized, whereas data from New York were collected at any location at any time. For each city, we evaluated whether the number of observers, observation days (days on which observations were reported), and sampling locations were associated with the reported proportion of the estimated regional pool of butterfly species. We also compared the number of volunteers, duration of volunteer involvement, and consistency of sampling efforts at individual locations within each city over time. From 2001 to 2010, there were 73 volunteers in Chicago and 89 in New York. During this period, volunteers observed 86% and 89% of the estimated number of butterfly species present in Chicago and New York, respectively. Volunteers in New York reported a greater proportion of the estimated pool of butterfly species per year. In addition, more species were observed per volunteer and observation day in New York, largely due to the unrestricted sampling season in New York. Chicago volunteers were active for more years and monitored individual locations more consistently over time than volunteers in New York. Differences in monitoring protocol--especially length of sampling season and selection protocol for monitoring locations--influenced the relationship between species accrual and sampling effort, which suggests these factors are important in volunteer-based species-monitoring programs.     

洛阳市不同功能区地表灰尘重金属的粒径分布特征

以洛阳市为例,分析了工业区、商业区、居民区、城乡结合处、城市绿地和城市主干道等不同功能区地表灰尘颗粒组成及重金属（Cu、Zn、Pb、Cd）粒级效应。结果表明：洛阳市不同功能区地表灰尘粒径分布具多峰性,分别在850~250、150~96及〈75μm出现分布峰值。不同功能区地表灰尘粒径差异显著,居民区和城市绿地细颗粒比重较大,工业区和城市主干道粗颗粒相对较多。各金属元素的质量分数粒级效应不一,Pb在工业区各粒级中质量分数最高,具粒级效应,其它功能区粒级效应不明显,Cd、Cu粒级效应明显,Cd富集更趋向于细粒（96~75和〈75μm）,Cu在180~150μm粒径质量分数迅速升高,并随着粒径减小,基本呈上升趋势,除工业区和城乡结合部外,其它功能区均在〈75μm粒径达到峰值。除居民区和城乡结合部各粒径Zn分布较平均外,Zn主要富集于180~150μm粒径颗粒,且质量分数明显高于其它各粒级,粒级效应基本呈现正态分布。     

水资源约束下江苏省城镇开发安全预警

城镇规模的扩张离不开水资源的支撑,水资源承载力是影响城镇开发的重要因素。论文提出一种以水资源约束测算城镇开发度阈值及从"状态-趋势-效应"尺度进行开发度预警的方法,并以江苏省为例进行实证探索,最终划分综合预警分区。结果显示:到2020年,苏州、 无锡、 常州、 南京将成为重度预警区;徐州、 连云港为高度预警区;镇江、 扬州、 泰州、 南通为中度预警区;淮安、 宿迁、 盐城为轻度预警区。利用GM(1,1)模型和相关方程,对城镇开发度、 开发容量、 开发临界时点及开发后温度变化与碳汇损益定性定量化,进行整个开发过程的模拟,客观反映城镇开发安全变化的动态性,以期为政府制定差别化的开发政策和预警措施提供科学依据和理论支撑。     

基于熵值法和GM(1,1)模型的重庆城市生态系统健康评价

应用信息熵值反映数据本身的效用值来计算指标权重系数,建立熵权综合评价模型,对重庆城市生态系统健康进行了评价.根据评价结果和灰理论数学建模特点,建立GM(1,1)灰色预测模型,对重庆市生态系统健康进行了动态预测分析.结果表明:2005~2009年期间,重庆城市生态系统健康总体水平良好,其中各要素指数评价大小依次是活力指数、恢复力指数、组织结构指数、服务功能指数、人群生活指数;2010~2015年期间,重庆城市生态系统健康综合评价值将以e0.1268的增速保持良好发展态势.此外,建立以熵权综合评价为基础的GM(1,1)灰色预测模型对城市生态系统健康进行评价,能够得出更客观、更全面的评价结果.     

长江三角洲城市内河环境治理的居民支付意愿比较研究 ——上海、南京与杭州实例调查

应用意愿价值评估法(CVM)的技术调查上海、南京和杭州城市内河环境治理的居民支付意愿,并探讨研究结果是否在城市间保持稳定.基于1258份问卷的统计分析,结果显示:上海、南京和杭州居民的支付意愿均值分别为20.5,25.4,20.3元/(户×月);进一步的线性对数模型分析结果表明,收入、环境意识等变量在3城市都呈现显著影响,而户籍、教育等因素在各城市模型中存在显著性差异;3城市混合数据模型显示,南京样本支付意愿显著高于其他2城市样本,杭州与上海调查样本无显著性差异.上述结果揭示了不同城市居民对城市内河治理的支付意愿呈现稳定性,为意愿价值评估法在我国不同区域间的“效益转移”研究提供了实证支持.但另一方面,参数模型表现出一定的差异,需要对模型作进一步的优化.