Prospects for mitigating carbon,conserving biodiversity,and promoting socioeconomic development objectives through the clean development mechanism

Should forest-based climate mitigationmeasures be approved for crediting through the CleanDevelopment Mechanism (CDM), they could offer anopportunity to accomplish three important objectives:cost-effective reductions in carbon emissions andsequestration of atmospheric carbon; conservation andrestoration of forests and their biological diversity;and, the assistance of host countries and communitiesin their socioeconomic development. However,prospective investors in CDM projects, host countriesand other CDM `stakeholders' might be expected toplace widely different priorities on achieving theseobjectives. This paper describes several factors thatwill affect investor interest in CDM projects, thecharacteristics of forest-based CDM projects that willattract investments, and an approach to identifyingprojects that meet the key objectives of multiplestakeholders. This approach entails identifyingsites, such as degraded watersheds, where CDMfinancing for forest conservation and restoration cangenerate readily monetizable local and regionalsocioeconomic benefits, while mitigating carbonemissions in forests with importance for conservingbiodiversity.     

北京土地利用/覆盖变化机制研究

利用７０年代、８０年代和９０年代（ＳＰＯＴ）３个时段北京市土地利用资料进行土地利用／覆盖研究,分析其变化机制。北京土地利用变化的形式主要以轴向扩展、卫星城建设、工厂郊迁、郊区大型中价商城建设、郊外别墅区等为主,土地覆盖变化的主要形式有：①内城更新与改造;②商贸街的重建;③粗放型用地向集约型用地的转变。     

太湖流域土地利用变化及洪涝灾害响应

根据1986年和1996年土地资源调查和土地详查资料,分析了太湖流域土地利用的数量变化和空间变化,揭示了该区土地利用变化的幅度、速度、区域差异,以及土地利用变化的驱动力。根据1991年汛期(5～9月)降雨,分别计算了1986、1996年下垫面状况下的产水量,比较了二期产水数量和空间分布的差异,分析了20世纪90年代以来流域水位连续偏高的原因,进而分析洪涝是如何对土地利用的变化作出响应的。太湖流域土地利用变化的特征是耕地面积快速减少和建设用地迅速增加,土地利用变化的驱动力是政策因素、经济发展和人口增长。太湖流域10年间土地利用变化使流域产水量增加,洪涝过程缩短,增加的产水分布在流域的上游,加重了流域的洪涝灾害。     

长江三角洲耕地数量变化趋势及总量动态平衡前景分析

论文利用长江三角洲地区近50年长序列耕地统计、近10多年土地利用调查数据及相关社会经济资料,重点从长江三角洲耕地数量变化的阶段性及与经济发展水平之间关系宏观分析的角度,探讨该区未来10～15年耕地变化趋势及实施区域耕地总量动态平衡的可能性。分析表明,长江三角洲耕地面积随人均GDP的增长呈良好的指数减少关系,人均GDP低于12000元/人,经济增长占用耕地的压力较大;人均GDP超过30000元/人时,这种压力将开始显著减缓。现阶段长江三角洲仍处于经济发展对耕地的压力较大的发展阶段,但已较1995年前明显减轻,估计至2004年前后,该区经济增长对耕地的压力将开始得到缓解。按现有的土地复垦整理补充耕地的投资力度,至2010年耕地面积仍将比1998年减少5.5×104hm₂左右,若加大复垦整理的投资力度至现状水平的2倍,则保持耕地数量不减少也是可能实现的。     

A spectral power analysis of driving behavior changes during the transition from nondistraction to distraction

Objective: This article investigated and compared frequency domain and time domain characteristics of drivers' behaviors before and after the start of distracted driving.

Method: Data from an existing naturalistic driving study were used. Fast Fourier transform (FFT) was applied for the frequency domain analysis to explore drivers' behavior pattern changes between nondistracted (prestarting of visual–manual task) and distracted (poststarting of visual–manual task) driving periods. Average relative spectral power in a low frequency range (0–0.5 Hz) and the standard deviation in a 10-s time window of vehicle control variables (i.e., lane offset, yaw rate, and acceleration) were calculated and further compared. Sensitivity analyses were also applied to examine the reliability of the time and frequency domain analyses.

Results: Results of the mixed model analyses from the time and frequency domain analyses all showed significant degradation in lateral control performance after engaging in visual–manual tasks while driving. Results of the sensitivity analyses suggested that the frequency domain analysis was less sensitive to the frequency bandwidth, whereas the time domain analysis was more sensitive to the time intervals selected for variation calculations. Different time interval selections can result in significantly different standard deviation values, whereas average spectral power analysis on yaw rate in both low and high frequency bandwidths showed consistent results, that higher variation values were observed during distracted driving when compared to nondistracted driving.

Conclusions: This study suggests that driver state detection needs to consider the behavior changes during the prestarting periods, instead of only focusing on periods with physical presence of distraction, such as cell phone use. Lateral control measures can be a better indicator of distraction detection than longitudinal controls. In addition, frequency domain analyses proved to be a more robust and consistent method in assessing driving performance compared to time domain analyses.     

Carbon sequestration via afforestation as a sustainable action to mitigate climate change in Western Iran

Climate change involves increasing atmospheric carbon dioxide concentration which is driven by anthropogenic emissions. Afforestation, which is the establishment of forests on previously non‐forested lands, could be a suitable climate change mitigation strategy. The aim of this research is to evaluate the carbon sequestration capability of the Eucalyptus and Prosopis species in the Reza‐Abad afforestation park in western Iran. For this aim, three stands of any species were selected. For quantitative assessment, a transect was implemented at the length of 100 m. In trees located of transects, the general characteristics of species were measured. Also, for estimating the amount of litter, a sample plot has been measured at the center of the quadrate. These samples were taken from the afforested area, the control area inside the afforested area and another control area outside. In each stand, species were selected randomly and one‐eighth of the whole stand was taken for calculating the percentage of carbon and aerial biomass. Then the aboveground organs were weighted and after the transfer of different plant organs to the laboratory, the conversion factor of carbon sequestration of the plant organs was determined individually by combustion method. Also, soil samples were also collected from two depths of 0–15 and 15–30 cm in each of the cultivated and control parts. The results showed that there is a significant difference between the species and Prosopis has higher carbon sequestration than Eucalyptus. The carbon sequestration among different organs showed a significant difference, carbon sequestration was 19.24 t/ha for Eucalyptus and 18.43 t/ha for Prosopis. After an economic calculation, it was concluded that afforestation has a positive effect on the reduction of atmospheric carbon dioxide. Hence, these results allow decision makers to change land use from desert area to forest, and planting the Prosopis species is more recommendable than Eucalyptus for afforestation in such areas which are economically profitable.     

Climate adaptation management and institutional erosion: insights from a major Canadian port

This paper performs an institutional analysis of the adaptation to climate change by ports, through a case study of the port of Vancouver, Canada. While previous literature has demonstrated the value of informal institutions for filling gaps left by formal institutions, the role of failed informal institutions has received less attention. Our analysis reveals how, in the case of an unprecedented challenge like climate adaptation, relying on informal institutions with less agency can actually erode the strength of existing institutions in a form of negative institutional plasticity. In this case, emerging polycentric governance was unsuccessful, unable to construct clearly demarcated responsibilities due to impedance by the path dependence of the current federalist system. The latter works well for traditional infrastructure investments with a closed pool of stakeholders, but not for ports where multiple scales of embeddedness, both horizontally and vertically, produce a collective action problem with no mechanism for resolution.     

Special section: advancing the role of cities in climate governance – promise,limits, politics

This special issue contributes to scholarly debates about the role of cities in global climate governance, reflecting on the promise, limits, and politics of cities as agents of change. It takes an empirically-informed approach drawing on multiple diverse geographical and political contexts. Overall, the special issue aims to stimulate reflection and debate about where understanding and practice needs improvement to advance the role of cities in global climate governance. Key questions that are addressed in the special issue include: To what extent do real world experiences confirm or disconfirm the high expectations of cities as agents and sites of change in addressing global climate change as expressed in urban climate governance literature? In what ways do internal political dynamics of cities enable or constrain urban climate governance? How is climate governance in cities enabled and constrained by interactions with broader governance levels? In what ways can climate governance in cities be advanced through critical attention to the previous issues?     

What Matters Most: Are Future Stream Temperatures More Sensitive to Changing Air Temperatures,Discharge, or Riparian Vegetation?

Simulations of stream temperatures showed a wide range of future thermal regimes under a warming climate — from 2.9°C warmer to 7.6°C cooler than current conditions — depending primarily on shade from riparian vegetation. We used the stream temperature model, Heat Source, to analyze a 37‐km study segment of the upper Middle Fork John Day River, located in northeast Oregon, USA. We developed alternative future scenarios based on downscaled projections from climate change models and the composition and structure of native riparian forests. We examined 36 scenarios combining future changes in air temperature (ΔT_air = 0°C, +2°C, and +4°C), stream discharge (ΔQ = ?30%, 0%, and +30%), and riparian vegetation (post‐wildfire with 7% shade, current vegetation with 19% shade, a young‐open forest with 34% shade, and a mature riparian forest with 79% effective shade). Shade from riparian vegetation had the largest influence on stream temperatures, changing the seven‐day average daily maximum temperature (7DADM) from +1°C to ?7°C. In comparison, the 7DADM increased by 1.4°C with a 4°C increase in air temperature and by 0.7°C with a 30% change in discharge. Many streams throughout the interior western United States have been altered in ways that have substantially reduced shade. The effect of restoring shade could result in future stream temperatures that are colder than today, even under a warmer climate with substantially lower late‐summer streamflow.     

Climatic Controls on Watershed Reference Evapotranspiration Varied during 1961–2012 in Southern China

Reference evapotranspiration (ET_o) is an important hydrometeorological term widely used in understanding and projecting the hydrological effects of future climate and land use change. We conducted a case study in the Qinhuai River Basin that is dominated by a humid subtropical climate and mixed land uses in southern China. Long‐term (1961–2012) meteorological data were used to estimate ET_o by the FAO‐56 Penman–Monteith model. The individual contribution from each meteorological variable to the trend of ET_o was quantified. We found basin‐wide annual ET_o decreased significantly (p < 0.05) by 3.82 mm/yr during 1961–1987, due to decreased wind speed, solar radiation, vapor pressure deficit (VPD), and increased relative humidity (RH). However, due to the increased VPD and decreased RH, the ET_o increased significantly (p < 0.05) in spring, autumn, and annually at a rate of 2.55, 0.56, and 3.16 mm/yr during 1988–2012, respectively. The aerodynamic term was a dominant factor controlling ET_o variation in both two periods. We concluded the key climatic controls on ET_o have shifted as a result of global climate change during 1961–2012. The atmospheric demand, instead of air temperature alone, was a major control on ET_o. Models for accurately predicting ET_o and hydrological change under a changing climate must include VPD in the study region. The shifts of climatic control on the hydrological cycles should be considered in future water resource management in humid regions.