东北平原西部沙地的气候变异与土地荒漠化

东北平原西部沙地位于欧亚大陆中纬度巨型沙带的东部边缘 ,为我国荒漠化土地的东缘。随着经济的发展 ,生态环境遭到严重破坏 ,荒漠化景观日益明显 ,前景令人堪忧。气候因素是荒漠化发展的一个基本因素 ,东北平原西部沙地是我国北方气候条件最好的沙区 ,但目前对于区域荒漠化驱动因子的气候因素影响方面的研究未开展系统的工作。论文系统分析了东北平原西部沙地影响荒漠化的现代气候因素特点 ,探讨了在较好气候条件下气候变异、人类活动与荒漠化之间的关系 ,并根据气候发展趋势预测了未来在自然因素作用下沙地的可能发展趋势。     

气候变暖对黑龙江省作物生产的影响及其对策

黑龙江省在未来30年和50年内气温分别增高1.9℃和2.4℃的情景下,积温带将向北推移近5个纬距,至2050年,原第一积温带将北移至大兴安岭北部,其余4个积温带将基本消失.模拟结果显示,未来水稻将减产9%,主栽区将北移至黑龙江流域;小麦应压缩耕作面积,未来产量变化不大,应逐步扩大冬小麦试种区域,最后达到规模生产;气候变暖使玉米生育期缩短11.3天,产量减少2.7%,应发展早熟玉米、饲料玉米、经济玉米,提高经济效益;气候变暖对大豆生产极为有利,高产区北移,产量可提高70%～80%,在黑龙江流域松嫩和三江平原北部,特别垦区发展大豆生产优势很大;喜凉经济作物受到一定影响,应向北发展.提出了未来适应性农业的6项对策,特别要安排好主要作物的结构调整及区域分布.     

ALGAL PRODUCTIVITY AND NITRATE ASSIMILATION IN AN EFFLUENT DOMINATED CONCRETE LINED STREAM1

This study examined algal productivity and nitrate assimilation in a 2.85 km reach of Cucamonga Creek, California, a concrete lined channel receiving treated municipal wastewater. Stream nitrate concentrations observed at two stations indicated nearly continuous loss throughout the diel study. Nitrate loss in the reach was approximately 11 mg/L/d or 1.0 g/m²/d as N, most of which occurred during daylight. The peak rate of nitrate loss (1.13 mg/l/hr) occurred just prior to an afternoon total CO₂ depletion. Gross primary productivity, as estimated by a model using the observed differences in dissolved oxygen between the two stations, was 228 mg/L/d, or 21 g/m²/d as O₂. The observed diel variations in productivity, nitrate loss, pH, dissolved oxygen, and CO₂ indicate that nitrate loss was primarily due to algal assimilation. The observed levels of productivity and nitrate assimilation were exceptionally high on a mass per volume basis compared to studies on other streams; these rates occurred because of the shallow stream depth. This study suggests that concrete‐lined channels can provide an important environmental service: lowering of nitrate concentrations similar to rates observed in biological treatment systems.     

气候异常与中国小麦白粉病灾害流行关系的研究

分析了厄尔尼诺事件与我国冬小麦白粉病发病面积的相关关系。结果表明：在厄尔尼诺出现的起始年，冬小麦白粉病发病面积相对较小；在厄尔诺起始年至下一个厄尔诺起始年前的前一年，冬小麦白粉病发病面积趋势逐年增大，并在下一个厄尔尼诺起始年前一年达到最大值；在连续出现厄尔尼诺的年份，冬小麦白粉病发生面积逐年降低。厄尔尼诺事件通过引发主要麦区的诱水、温度异常来影响小麦白粉病的流行程度。造成厄尔尼诺年我国小麦白粉病发病面向相对较低的原因，与厄尔尼诺起始年前的冬半年寒潮活动加强造成冬小麦冻害严重，大大降低了小麦白粉菌的越冬基数及春季干旱不利于小麦白粉菌的侵染有关。     

Climatic Variation and Solute Concentration and Flux in Meltwaters Draining from an Alpine Glacier

Measurements of electrical conductivity and discharge ofmeltwaters in the Gornera, which drains from the 83%glacierised basin containing Gornergletscher, PennineAlps, Switzerland, were undertaken between May andSeptember in both 1979 and 1998. Discharge in theGornera was 43% higher in 1998, average air temperatureduring the ablation season being 2.1 °C warmer andpreceding winter precipitation 28% lower than in 1979. Mean electrical conductivity of meltwater in 1998 wasreduced by 40%. In the same 60 day period in 1998,however, solute flux was augmented by only 2% bycomparison with 1979. Year-to-year climatic variations,reflected in discharge variability, strongly affectsolute concentration in glacial meltwaters, but havelimited impact on solute flux. Climatic conditionstranslate into meltwater quality through inter-relationships between mineral reaction rates, subglacialresidence time in contact with sediment, and discharge. Annual variability in solute flux depends on the extentto which volume of flow can offset decline in soluteconcentration brought about by reducing residence time.     

INITIAL RESEARCH INTO CLIMATIC CHANGES AND GRASSLAND DEGENERATION IN INNER MONGOLIA

DuringtheimplementationoftheWestChinaDevelopmentStrategyinthetwenty firstcentury ,thenorthernsteppezoneplaysasignificantroleinsafeguardingtheecologicalsecurityandrealizingsustainabledevelopmentinChina .InnerMongoliaprairieliesinthemiddleofEurasiasteppezoneandisthetransitionzonefromthearidareasinthenorthwesttothehumidareasinthenortheastandthedryfarmingareasinNorthChina .Therigorousnaturalconditions ,thefluctuatingclimateandthecompli catedsocialandeconomicconditionsmakethisareaverysensitiveto…     

Securing water for people, crops, and ecosystems: New mindset and new priorities

A fundamentally new approach to water and human development will be needed during this new century if we are to secure sufficient freshwater to meet the needs of some 9 billion people while at the same time protecting the critical ecosystem services upon which the human economy depends. Signs of unsustainable water use — including falling water tables, shrinking lakes, and the drying up of rivers and streams — are widespread and spreading. In many regions, greater modification and appropriation of freshwater systems for human purposes will yield greater costs than benefits and create the risk of irreversible losses of species and ecosystem services. A new mindset is needed to guide water use and management in this new century, one that views the human water economy as a subset of nature's water economy. Living within nature's limits will require that societies satisfy the basic needs of people and ecosystems before non-essential water demands are met. It will require on the order of a doubling of water productivity. And it will require stronger institutions to encourage equitable sharing of water to alleviate tensions within and between countries.     

基于BML生产率指数的中国旅游业能源效率评价与影响因素研究

为减少旅游业能源消耗,实现旅游低碳绿色发展,探讨如何提高旅游业能源效率,基于包含非期望产出的方向性距离函数,首先构建了适应旅游业的Biennial Malmquist-Luenberger(BML)效率指数,以中国30个省市2005~2013年旅游业为实证对象,测度了其能源效率,9 a来旅游业能源效率变化源泉可被分解为全要素生产率、资本对能源替代效应、劳动对能源替代效应、能源结构效应和产出结构效应5项影响因素。研究发现:(1)中国旅游业能源效率整体上处于较低水平,旅游业能源效率可以扩张提升的比例较大。(2)整体上全要素生产率、资本对能源替代效应、劳动对能源替代效应和能源结构效应的提升能促进旅游业能源效率提高。(3)近3 a来劳动和资本投入的能源替代效应对旅游业能源效率变化的作用超过了全要素生产率。(4)区域层面上,东部地区旅游业能源效率高于中西部地区,主要由地区间旅游业对资本投入使用和能源消耗结构的差异造成。(5)整个样本期间,中国17个省市旅游业能源效率呈现下降趋势,背后的因素各有不同,旅游业资本替代效应是湖北省、福建省和浙江省等多数省市旅游业能源效率下降的主要因素,全要素生产率是安徽省、海南省、贵州省和甘肃省旅游业能源效率下降的主要原因。因此,合理利用投入的资源要素对旅游业低能耗发展至关重要,尤其是要发挥好资本对能源的替代效应,高效的资本配置能极大提高旅游能源效率。     

The interplay between climate change and disaster risk reduction policy: evidence from Mexico

Mexico gained worldwide reputation for its efforts to develop both climate change (CC) and disaster risk reduction (DRR) policies at the national and international levels. However, the integration of agreements such as the Kyoto Protocol and the Hyogo and Sendai Frameworks into the national institutional setting has been challenging in terms of creating a coherent national risk reduction policy. The purpose of this paper is to analyse the interplay between DRR and CC domains; it provides evidence for the situation in Mexico by comparing the institutions and main actors in both fields as well as the financial and operational instruments currently in force. The comparison is based on institutions’ jurisdictions, priorities and lines of action. This paper synthesises the most important policy instruments, their meeting points and their contradictions and discusses the implications of such policy setting for the implementation of effective CC risk policies. The study depicts a fragmented policy interface with serious shortcomings in terms of the institutional design necessary to coordinate actions. The article concludes that, despite the multiple conceptual and political intersections between both policy fields, the implementation of specific, shared actions would hardly overcome the difficulties imposed by the current, fragmented normative frameworks and jurisdictions.     

2000—2014年中国经济系统物质流核算与资源产出率研究

本文利用经济系统物质流分析框架核算了我国2000—2014年的主要物质流、资源产出率等指标。结果表明：① 2000—2014年本地采掘物质量、进口量和本地处置后排放均有较快增长。2011—2014年本地采掘中生物质采掘量逐年稳步增长,非金属矿石和化石燃料采掘量处于下降趋势。本地处置后排放中空气排放物贡献了绝大部分比例并逐年增长,水污染排放物逐年下降。② 2000—2014年人均资源的采掘、投入和消耗量均有大幅增长,2014年人均物质消耗量比2000年增长1倍以上。资源产出率和单位GDP本地采掘、投入物质量处于波动式增长趋势,本地采掘每吨物质所贡献的GDP已连续三年超过资源产出率。③ 2014年中国资源产出率约为欧盟28国平均水平的1/4。2010年我国省级资源产出率差异较大,小部分地区已超过欧盟同期水平,但仍有大部分地区的资源产出率较低,未达到全国平均水平。