Emissions associated with meeting the future global wheat demand: A case study of UK production under climate change constraints

Climate change, population growth and socio-structural changes will make meeting future food demands extremely challenging. As wheat is a globally traded food commodity central to the food security of many nations, this paper uses it as an example to explore the impact of climate change on global food supply and quantify the resulting greenhouse gas emissions. Published data on projected wheat production is used to analyse how global production can be increased to match projected demand. The results show that the largest projected wheat demand increases are in areas most likely to suffer severe climate change impacts, but that global demand could be met if northern hemisphere producers exploit climate change benefits to increase production and narrow their yield gaps. Life cycle assessment of different climate change scenarios shows that in the case of one of the most important wheat producers (the UK) it may be possible to improve yields with an increase of only 0.6% in the emission intensity per unit of wheat produced in a 2 °C scenario. However, UK production would need to rise substantially, increasing total UK wheat production emissions by 26%. This demonstrates how national emission inventories and associated targets do not incentivise minimisation of global greenhouse gas emissions while meeting increased food demands, highlighting a triad of challenges: meeting the rising demand for food, adapting to climate change and reducing emissions.     

Testing the Environmental Kuznets Curve Hypothesis with Bird Populations as Habitat-Specific Environmental Indicators: Evidence from Canada

Abstract:  The traditional environmental Kuznets curve (EKC) hypothesis postulates that environmental degradation follows an inverted U-shaped relationship with gross domestic product (GDP) per capita. We tested the EKC hypothesis with bird populations in 5 different habitats as environmental quality indicators. Because birds are considered environmental goods, for them the EKC hypothesis would instead be associated with a U-shaped relationship between bird populations and GDP per capita. In keeping with the literature, we included other variables in the analysis—namely, human population density and time index variables (the latter variable captured the impact of persistent and exogenous climate and/or policy changes on bird populations over time). Using data from 9 Canadian provinces gathered over 37 years, we used a generalized least-squares regression for each bird habitat type, which accounted for the panel structure of the data, the cross-sectional dependence across provinces in the residuals, heteroskedasticity, and fixed- or random-effect specifications of the models. We found evidence that supports the EKC hypothesis for 3 of the 5 bird population habitat types. In addition, the relationship between human population density and the different bird populations varied, which emphasizes the complex nature of the impact that human populations have on the environment. The relationship between the time-index variable and the different bird populations also varied, which indicates there are other persistent and significant influences on bird populations over time. Overall our EKC results were consistent with those found for threatened bird species, indicating that economic prosperity does indeed act to benefit some bird populations.     

Trends in management plans and guides: 25 years of experience from Southern France

This study analysed 14 management plans and guidelines from a 25-year period to understand trends in conservation planning. A Rosetta Stone Analysis was used for the systematic comparison of plans and guidelines. Management plans incorporated management philosophies, management scenarios, opportunities for infrastructure, and plans for data collection by 2000. As of 2010, they incorporated ecosystem services, stakeholders’ objectives and methods for storing and analysing data. The results demonstrate the complex nature of management plans, with an important workload for site managers. Recommendations for future planning include adjustments in planning timeframes and a better identification of conservation targets from initial stages.     

Evaluating Alternative Temporal Survey Designs for Monitoring Wetland Area and Detecting Changes Over Time in California

Evaluation of wetland extent and changes in extent is a foundation of many wetland monitoring and assessment programs. Probabilistic sampling and mapping provides a cost‐effective alternative to comprehensive mapping for large geographic areas. One unresolved challenge for probabilistic or design‐based approaches is how best to monitor both status (e.g., extent at a single point in time) and trends (e.g., changes in extent over time) within a single monitoring program. Existing wetland status and trends (S&T) monitoring programs employ fixed sampling locations; however, theoretical evaluation and limited implementation in other landscape monitoring areas suggest that alternative designs could increase statistical efficiency and overall accuracy. In particular, designs that employ both fixed and nonfixed sampling locations (alternately termed permanent and temporary samples), termed sampling with partial replacement (SPR), are considered to efficiently and effectively balance monitoring current status with detection of trends. This study utilized simulated sampling to assess the performance of fixed sampling locations, SPR, and strictly nonfixed designs for monitoring wetland S&T over time. Modeled changes in wetland density over time were used as inputs for sampling simulations. In contrast to previous evaluations of SPR, the results of this study support the use of a fixed sampling design and show that SPR may underestimate both S&T.     

基于卫星遥感的浙北平原气溶胶光学特性长期变化分析

利用MOD04 C051气溶胶产品,以浙江北部平原为主要研究区,开展区域气溶胶光学特性长期(2000年3月—2013年12月)变化分析.长期逐月时间序列显示,区域气溶胶光学特性具有年内周期性变化规律,AOD(Aerosol Optical Depth)峰值多出现在5月或6月;Angstrom Exponent(α指数)峰值多出现在3月或4月.在空间分布上,研究区中部地区气溶胶污染较重且粗粒子成分较高.研究区气溶胶光学特性长期变化特征主要体现在:1气溶胶污染总体减轻但细粒子成分增加,复合污染加重;2008年以来区域AOD年均值总体呈下降趋势;2007—2013年α指数年均值显著高于2000—2006年;区域α指数月均值增长趋势显著,近14年的总倾向率为0.125(p0.05);2AOD和α指数的季节差异呈减小趋势,AOD的季节变化规律由2000年的春夏≈冬秋转变为2013年的春冬秋≥夏;α指数虽仍以夏秋季高于冬春季,但春秋两季α指数相对增大;3以污染较轻的湖州市和污染较重的嘉兴市为例的原因分析显示,AOD变化与SO2排放量具有一定相关性,α指数变化与民用汽车拥有量变化趋势一致,相关性较高.     

探索性数据分析在西藏气候变化趋势研究中的应用

为了减少小样本时间序列资料中个别异常值对气候变化趋势分析的破坏性影响,采用探索性数据分析方法之一的三组耐抗线对西藏近30年气温、云量资料进行线性趋势分析,研究了西藏地区气温和云量的变化趋势及其区域分布,并讨论了二者的相关特征。通过与传统的最小二乘法相比,表明三组耐抗线用于西藏气候变化趋势分析具有明显优势,而用最小二乘法得到的西藏气候变暖估计偏高。分析认为,西藏气候变暖主要由最低气温增高显著所致,最低气温变暖趋势在春、夏季较明显,冬季相对不明显;西藏各地增温幅度在空间分布上不一致,中、西部地区呈较强的增温趋势,东部相对较弱;西藏高原总云量和低云量总体呈减少趋势,总云量和低云量变少分别与西部和中部地区的升温之间存在显著负相关关系。     

Changing Drivers of Deforestation and New Opportunities for Conservation

Abstract: Over the past 50 years, human agents of deforestation have changed in ways that have potentially important implications for conservation efforts. We characterized these changes through a meta‐analysis of case studies of land‐cover change in the tropics. From the 1960s to the 1980s, small‐scale farmers, with state assistance, deforested large areas of tropical forest in Southeast Asia and Latin America. As globalization and urbanization increased during the 1980s, the agents of deforestation changed in two important parts of the tropical biome, the lowland rainforests in Brazil and Indonesia. Well‐capitalized ranchers, farmers, and loggers producing for consumers in distant markets became more prominent in these places and this globalization weakened the historically strong relationship between local population growth and forest cover. At the same time, forests have begun to regrow in some tropical uplands. These changing circumstances, we believe, suggest two new and differing strategies for biodiversity conservation in the tropics, one focused on conserving uplands and the other on promoting environmental stewardship in lowlands and other areas conducive to industrial agriculture.     

Concurrent Chemical and Histological Analyses: Are They Compatible?

Bivalves are often used as sentinel organisms in monitoring programmes for trace organic contaminants. the animal's physiological state may be important in interpreting trends in contaminant body burden. Simultaneous evaluation of physiological state and organic contaminant concentration in bivalves typically involves removal of a lipid-rich cross-section of the body mass for histopathological and/or gonadal analysis.

In this study, the bias introduced by this technique in the final trace organic concentrations, e.g. of polynuclear aromatic hydrocarbons, chlorinated pesticides and polychlorinated biphenyls, are evaluated on five different size groups of oysters. As a test case, we evaluated the use of this method in the NOAA's Status & Trends Mussel Watch (NS&T) Programme. the average biases introduced by this technique in the final trace organic concentrations in Gulf of Mexico oysters have been increasing since 1986 as a consequence of a continuous decrease in the size of the individuals sampled.     

污水分析方法监测城市毒品滥用长期趋势

毒品滥用问题是全球广泛关注的社会问题,对城市毒品滥用情况进行长期监测具有重要意义.采用污水流行病学的方法,对大连市毒品的滥用情况进行连续长期调查.2020～2021年采集大连市22个污水处理厂的进口污水,通过气相色谱衍生化方法分析测定甲基苯丙胺、海洛因、氯胺酮、摇头丸和可卡因的生物标志物的浓度,即其尿液代谢产物甲基苯丙胺、吗啡、氯胺酮、摇头丸和苯甲酰芽子碱.结果表明,2020年p(甲基苯丙胺)、p(吗啡)和p(氯胺酮)均值分别为23.69、23.21和2.40 ng·L-1;2021年均值分别为20.64、20.92和0.47 ng·L-1,在所有的污水样品中均未检测出摇头丸和苯甲酰芽子碱,根据相关信息估算5种毒品的人均滥用量,并结合往年监测数据分析大连市这5种毒品的滥用趋势.甲基苯丙胺和海洛因滥用量均在2019年有上升趋势,2020大幅度下降,2021年基本保持不变;氯胺酮的滥用则一直处于较低水平.本研究为大连市实时监控毒品滥用情况提供科学依据,对防治毒品犯罪具有重要意义.     

汉江流域1951~2003年降水气温时空变化趋势分析

利用Mann Kendall检验方法和空间插值方法，分析了1951~2003年汉江流域年和春、夏、秋、冬四季降水和气温变化趋势的时空分布，并重点分析了丹江口水库上游年降水、年平均气温和北半球气温的变化趋势及相互间的联系。分析发现，在显著性水平α=0.1上，近50年来汉江流域大部分地区降水没有明显的变化趋势，气温呈上升趋势。丹江口水库上游降水在1991年发生突变，从20世纪80年代多雨期进入90年代少雨期，80年代平均降水比1951~2003年多年平均降水多9.7%，90年代平均降水比多年平均降水少11.6%；上游平均气温90年代比多年平均气温高0.2℃，而同期北半球的平均气温也比多年平均高了0.3℃，上游气温同北半球气温同步上升，而上游降水变化受北半球气温升高的影响不断减少，两者之间存在反相关系。分析成果有助于进一步研究气候变化对汉江流域水资源和防洪安全的影响，也将为南水北调中线工程的顺利实施提供科学依据。