重要生态用地级别评价和划定方法研究——以水源涵养为例

文章以水源涵养为例,基于水平衡评价计算方法,选择水资源禀赋类型不同的县域单元开展水源涵养型生态用地功能分级划定研究。总结现有生态保护红线划定技术方法及存在不足,致力于显化不同地区水源涵养生态用地功能绝对值差异,利用评价单元格水源涵养累计贡献值面积弹性拐点,对重要水源涵养用地级别划定方法进行改进。对河北省易县和四川省金川县的实例验证表明,此评价方法可以根据不同地区水源涵养功能特点量身确定重要生态空间规模、面积和比例。     

基于PSR模型的北京市西北生态涵养区生态健康评价研究

研究目的:作为保障首都生态环境质量与可持续发展的关键区域,北京市西北生态涵养区的生态健康程度反映了生态文明战略部署下首都高质量发展的综合成效。本文通过构建北京市西北生态涵养区健康评价指标体系,评价该区域的生态健康程度,为生态涵养区的可持续发展提供对策建议。研究方法:PSR模型、层次分析法(AHP)。研究结果:(1)基于PSR模型构建的生态健康评价指标体系包括压力、状态和响应系统3个准则层和10个评价指标,涵盖涵养区自然生态和人类活动影响;(2)研究区4个时段的健康指数分别为0.673、0.664、0.650、0.687,生态健康等级为一般。研究结论:北京市西北涵养区生态健康状况较为稳定,在保持西北涵养区建设现有成果的基础上,需要加大生态建设的力度,进一步提高生态健康水平。     

咸阳城区表层土壤重金属污染特征及生态健康风险评价

在咸阳市区采集表层土壤样品60个,包括交通主干道路两侧、城市公园、住宅小区、工矿企业周边区域4类典型功能区。采用原子吸收分光光度法测定土壤样品中Cr(铬)、Cu(铜)、Ni(镍)、Pb(铅)、Zn(锌)5种重金属的含量,运用污染指数评价法、潜在生态风险指数法对土壤重金属的污染现状及风险进行评价。结果表明:(1)咸阳市土壤中Cr、Cu、Ni、Pb、Zn 5种重金属的平均含量分别为65.11、26.91、29.81、38.26、90.94mg/kg,均超过陕西省土壤重金属元素背景值;不同城市功能区土壤重金属含量水平具有明显的差异。(2)从土壤重金属单因子污染指数来看,除重金属Pb在城市公园为中度污染外,其余元素在不同功能区及整个咸阳市均为轻度污染;从土壤重金属综合污染指数来看,不论是咸阳市还是不同功能区,其土壤环境质量等级均属于轻污染。(3)不论是综合潜在生态风险还是单个重金属元素潜在生态风险,咸阳市及不同功能区都属于低生态风险水平,且重金属Pb对综合潜在生态风险的贡献率最大(37.56%)。(4)5种重金属(Cr、Cu、Ni、Pb、Zn)对儿童和成人的非致癌风险均很小;人体(儿童和成人)暴露土壤中,Ni的综合致癌风险在可接受范围内,但明显高于下限值,而Cr的综合致癌风险则是显著的;人体(儿童和成人)暴露土壤重金属而产生的非致癌风险和致癌风险的主要途径是直接摄入和皮肤接触。     

The new ecological paradigm and responses to climate change in China

The purpose of this study was to develop and evaluate a Chinese-Mandarin version of the revised new ecological paradigm (NEP-R) scale. In a sample of 515 Mandarin-speaking Chinese nationals, we first assessed the factor structure and internal consistency of the NEP-R and assessed its validity by examining associations with global warming risk perceptions and mitigation behavior. Respondents completed the NEP-R scale, together with measures of risk perception and mitigation behavior. Exploratory and confirmatory factor analyses indicated that a two-factor solution, reflecting ecocentric and anthropocentric worldviews, best fit the data. Multi-group path analysis revealed that respondents with stronger ecocentric and weaker anthropocentric worldviews perceived more risks associated with global warming. In turn, respondents who perceived more risks reported engaging in more global warming mitigation behaviors. But importantly, the path between risk perceptions and behavior was significantly stronger for highly educated respondents than for less educated respondents, suggesting that education may represent an important strategy for bridging the gap between perceived risks about global warming and action.     

自然生态空间用途管制分区划定研究——以平潭岛为例

研究目的:在明确自然生态空间内涵和分类的基础上,探讨自然生态空间用途管制分区划定的逻辑框架和技术方法,提出自然生态空间分类、分级管制规则。研究方法:文献综述与GIS空间分析。研究结果:根据不同自然生态系统类型及其空间分布特征将自然生态空间类型划分为森林生态空间、草地生态空间、湿地生态空间和荒地生态空间;基于景观功能识别并按不同管控等级将自然生态空间管制类型区划分为红线区、橙线区和黄线区;同时,依据不同地块主要功能进一步确定自然生态空间用途管制分级,划定用途管制分区结果。研究结论:基于"区域主体功能—景观主导功能—地块主要功能"的自然生态空间管制分区划定逻辑框架,可为构建以功能分类、用途分区、管控分级为导向的自然生态空间用途管制体系提供理论依据和实践借鉴。     

Cost Analysis of Calcium in Store Brand versus National Brand Grocery Products

Objective: This study was to determine if calcium fortification yields a higher price per serving in grocery store products. Researchers compared store brand to national brand grocery products in relation to cost in order to examine if calcium values were similar between store brand and national brand products. Methods: A total of 112 store brand and 211 national brand grocery products were collected from three low (national chain store), middle and high priced (Virginia and North Carolina regional store) grocery venues. Products were compared using price and calcium percentage per serving. ANOVA was used to determine between store brand and national brand for price per serving and calcium content, and between grocery venues. Results: National brand fortified products had a significantly lower mean price per serving when compared to national brand non-fortified products (p = 0.0002). There was no statistical difference between store brand fortified and non-fortified products (p = 0.9256). Low priced store brand products had the lowest mean price per serving ($0.34 ±0.24). Conclusions: This study found store brand products have similar calcium content as national brand products. Product cost was lower at low priced store compared to middle and high priced stores.     

Land use regulation and urban land value: Evidence from China

Land use regulation has always been regarded as one of the most crucial means of macro-control of urban growth, which can affect a city’s land values directly and further determine related urban economic well-being. Since the New Type Urbanization Strategy proposed by the government in 2014, China’s mode of urban growth has been transformed from addressing “quantity” to “quality" in the urbanization process. In this case, the regulation of land use by the Chinese government plays a more important role in urban growth. With their planned land regulatory scheme, the various instruments employed by Chinese governments have quite different mechanisms influencing land prices. However, there are no rigorous studies focusing on the land use regulation system and its impact on land values to date, particular in China. This study seeks to explore how land use regulation affects urban land values through the systematic lens. We summarize the main land use regulatory instruments based on the analysis of China’s planned land use system and urban land banking system, including the construction land quota, constraints on the allowed floor area ratio (FAR) of each land transaction parcel, and land supply restrictions. A new dataset based on land transaction data from 2007 to 2016 that covers 286 prefectural cities from the country’s coastal, central, and western regions is used in the empirical analysis. The results show that the effects of the floor area ratio (FAR) on land values are significant and positive, with the residential and commercial land supply ratio being a key factor. Moreover, the results imply that the effects of constraints on FAR and commercial land supply vary between regions. These findings indicate that the Chinese land market is considerably distorted by excessive administrative interventions by local governments, in the stage of urban transition guided, the capable regulatory instruments could play an important role in adjusting urban land prices and hence impact on urban growth.     

Convergence between satellite information and farmers’ perception of drought in rangelands of North-West Patagonia,Argentina

Drought is a complex natural hazard with social and environmental implications. Satellite information is increasingly used to support decision-makers in preventing or coping with the negative impacts of drought. The integration of local and scientific knowledge to support drought monitoring is still far from being the main procedure in the development of drought monitoring and early warning systems. This study aimed at assessing the degree of convergence between satellite information on the effect of droughts on rangeland vegetation, from time series analysis, and farmers’ perception of drought in North-West Patagonia, Argentina. We characterised the scientific evidence of drought in terms of duration, spatial distribution, most severe years and recovery for the period 2000–2018 by identifying inter-annual NDVI changes. Farmers’ perceptions and experiences of drought were studied with open-ending interviews, with respect to occurrence, duration and recovery for that period. Satellite information matched farmers’ perception of drought at a regional scale, emphasising the value of remote sensing tools in supporting regional policy decision-making. However, farmers’ perceptions and recall of past drought impacts were more diverse than satellite information at a local level, highlighting the need for knowledge integration at finer scales.     

Labor migration and the decoupling of the crop-livestock system in a rural mountainous area: Evidence from Chongqing,China

Massive out-migration of rural labor force brings both challenges and opportunities to crop-livestock integrated production system (crop-livestock system) in smallholder economy. Compared with previous researches that have paid major attention to the effect of labor migration on either crop production or livestock husbandry, this study considers the mediating role of crop production in predicting the effect of labor migration on livestock raising. Our econometric estimation based on a 2012 survey of 974 rural households in Chongqing, a mountainous region of China, showed the following. (1) The massive migration of rural labor force had led to significant increase in farmland abandonment and considerable changes in the pattern of livestock raising. (2) The livestock raising number per household began to differentiate, with the livestock system separating from the traditional crop-livestock system and becoming a specialized business. (3) In terms of the pathways through which rural labor migration exerts impact on livestock raising number, though the increased opportunity costs of rural labor greatly reduced farmers’ willingness to raise livestock, the decoupling of the crop-livestock system partly alleviated the declining trend in the livestock raising number because of the availability of household labor force freed from cropping via farmland abandonment. These findings have important policy implications for rural development and agricultural restructuring in mountainous areas of China, and provide references for other developing countries.     

Data revisions to German national accounts: Are initial releases good nowcasts?

Data revisions to national accounts pose a serious challenge to policy decision making. Well-behaved revisions should be unbiased, small, and unpredictable. This article shows that revisions to German national accounts are biased, large, and predictable. Moreover, with use of filtering techniques designed to process data subject to revisions, the real-time forecasting performance of initial releases can be increased by up to 23%. For total real GDP growth, however, the initial release is an optimal forecast. Yet, given the results for disaggregated variables, the averaging out of biases and inefficiencies at the aggregate GDP level appears to be good luck rather than good forecasting.