ROLE OF WATERSHED SUBDIVISION ON MODELING THE EFFECTIVENESS OF BEST MANAGEMENT PRACTICES WITH SWAT1

Distributed parameter watershed models are often used for evaluating the effectiveness of various best management practices (BMPs). Streamflow, sediment, and nutrient yield predictions of a watershed model can be affected by spatial resolution as dictated by watershed subdivision. The objectives of this paper are to show that evaluation of BMPs using a model is strongly linked to the level of watershed subdivision; to suggest a methodology for identifying an appropriate subdivision level; and to examine the efficacy of different BMPs at field and watershed scales. In this study, the Soil and Water Assessment Tool (SWAT) model was calibrated and validated for streamflow, sediment, and nutrient yields at the outlet of the Dreisbach (623 ha) and Smith Fry (730 ha) watersheds in Maumee River Basin, Indiana. Grassed waterways, grade stabilization structures, field borders, and parallel terraces are the BMPs that were installed in the study area in the 1970s. Sediment and nutrient outputs from the calibrated model were compared at various watershed subdivision levels, both with and without implementation of these BMPs. Results for the study watersheds indicated that evaluation of the impacts of these BMPs on sediment and nutrient yields was very sensitive to the level of subdivision that was implemented in SWAT. An optimal watershed subdivision level for representation of the BMPs was identified through numerical simulations. For the study watersheds, it would appear that the average subwatershed area corresponding to approximately 4 percent of total watershed area is needed to represent the influence of these BMPs when using the SWAT model.     

A giant termite from the Late Miocene of Styria, Austria (Isoptera)

A giant termite is described and figured from the Late Miocene of the Styrian Basin in southeastern Austria. Gyatermes styriensis gen. n. et sp. n. is represented by a relatively complete forewing, with basal scale. The fossil approximates in size the largest of all termites today and is the largest fossil termite on record. The presence of this species in the Late Miocene fauna of Europe indicates that climatic conditions were appropriate for the persistence of species and colonies requiring relatively stable, warm conditions. The genus is primitive in overall features but shares some similarity with the dampwood termites.     

大型体育赛事对城市旅游的影响研究——以兰州国际马拉松为例

大型体育赛事的举办对城市旅游业发展具有巨大的刺激作用。以兰州国际马拉松为例,采用2000—2013年兰州旅游人数和旅游收入的统计数据,分析比赛前后几年旅游人数及旅游收入的变化。结果表明,兰州国际马拉松赛事对兰州旅游业发展的拉动作用极为明显。在此基础上,提出作为经济欠发达地区的兰州在发展以体育赛事为主的文化创意产业时所面临的问题及对策。     

澜沧江梯级水电站库区水体富营养化研究

根据2008年1—12月对澜沧江下游的漫湾和大朝山水电站库区的水环境监测结果,应用浮游植物指示法、地表水资源质量标准评价、经验TLI法评价、藻类现存量指标法对影响水体富营养化的水环境指标进行了分析。结果表明,两库区水体中,营养盐指标总体处在一种高含量水平,大朝山和漫湾库区水体总氮浓度年变化范围分别为0.345~1.880mg/L和0.340~1.743mg/L,总磷浓度年变化范围分别为0.019~0.139mg/L和0.015~0.111mg/L。TLI综合指数评价表明两库区水体处于贫营养水平。     

废旧弹药装药倒空方法的研究进展

随着弹药武器装备的更新换代,以及库存弹药超过储存年限,报废弹药销毁量越来越大,伴随出现的事故也越来越多,使得国内外对废旧弹药处理技术高效、安全、环保的要求也越来越高。基于废旧弹药的绿色回收利用技术,总结了废旧弹药装药倒空方法的国内外研究现状,分析了加热熔融、钻屑吸出、水射流冲洗、水力空化、低温冲洗、冷循环、超声振动及仿形钻削与干冰喷射复合8种倒药方法的优缺点,从高效、安全、环保和能否实现弹体与装药完全分离的角度,指出超声振动倒空法安全性好,倒空速度快,处理过程绿色无污染,可实现装药与壳体高效完全分离,具有广阔的发展前景,值得推广和深入研究;仿形钻削与干冰喷射复合倒空法集合了仿形钻削的高效率、无污染,能实现生产线的自动化控制,以及干冰喷射处理的炸药品种多、不存在"三废"等优点,是未来研究的主要方向之一。     

基于可持续生计的农村家庭灾后恢复研究

灾后恢复研究相对较少,是整个灾害治理/应急管理全流程(减灾、备灾、救灾和灾后恢复)中最需要加强的部分。目前大部分灾后恢复研究都侧重于物质重建,缺少全面的视角。本文借鉴被广泛用于发展领域内的可持续生计分析框架来分析农村家庭灾后恢复过程,希望为灾后恢复研究提供一个全面的视角,同时对可持续生计分析框架在灾害治理研究中的适用性进行一定的验证。本文所用数据来自于一项跟踪调查。研究地点为汶川地震某重灾县。首次问卷调查在2009年1月份开展,采用分层抽样方法,以访谈员面对面访问的形式,共在该县3个乡镇(9个村)调查了515户居民。第二次回访在2012年夏天进行,共完成415户家庭回访工作,回访率约为80.56%。通过对比两次调查所得415户相同农户家庭的生计资本(自然资本、金融资本,人力资本,物资资本,社会资本)数据,研究发现整体上农户所拥有的五类生计资本在灾后恢复阶段都有较大提升,其中物资资本增幅最高,其次是自然资本,金融资本,社会资本,增幅最小的是人力资本。生计资本在整体增加的同时,不同家庭间的物资、金融、人力和自然资本差距(标准差)也有所加大,但社会资本差距(标准差)有所减少。研究结果也从侧面证实了我国汶川地震灾后恢复主要侧重于物质重建,而且灾后恢复效果明显。同时,为灾难事件可以增强社会凝聚力提供了证据。跟踪调查中社会资本在灾后显著升高,而且不同家庭间的差距变小。研究表明,可持续生计分析框架可以为以家庭和社区为单元的灾害研究提供一个较好的分析工具。     

Proposal for an Indexical Method of Evaluating Risk of Hand Tool Operators’ Exposure to Mechanical Vibrations

The article presents proposals for an indexical evaluation of exposure of hand tool operators to vibrations. The presented indices have been developed on the basis of the results of laboratory tests. The examinations studied the effect of pressure force and grip force exerted by an operator on a hand tool as well as the amplitudes and frequencies of an exciting signal on vibrations transmitted in the hand-tool handle system.     

A Vibroacoustic Model of Selected Human Larynx Diseases

With the present development of digital registration and methods for processing speech it is possible to make effective objective acoustic diagnostics for medical purposes. These methods are useful as all pathologies and diseases of the human vocal tract influence the quality of a patient’s speech signal. Diagnostics of the voice organ can be defined as an unambiguous recognition of the current condition of a specific voice source. Such recognition is based on an evaluation of essential acoustic parameters of the speech signal. This requires creating a vibroacoustic model of selected deformations of Polish speech in relation to specific human larynx diseases. An analysis of speech and parameter mapping in 29-dimensional space is reviewed in this study. Speech parameters were extracted in time, frequency and cepstral (quefrency) domains resulting in diagrams that qualified symptoms and conditions of selected human larynx diseases. The paper presents graphically selected human larynx diseases.     

广西会仙岩溶湿地典型抗生素污染特征及生态风险评估

为确定会仙岩溶湿地不同介质中抗生素的污染特征及来源,利用液相色谱串联质谱联用仪分析了磺胺类(SAs)、氟喹诺酮类(FQs)和四环素类(TCs)三大类20种抗生素的含量.结果表明,研究区内水土介质监测的抗生素中共检出12种,检出浓度范围为n.d～106 ng·L~(-1),其中,甲氧苄氨嘧啶(TMP)的浓度最高.各环境介质中,以养殖用水和地表河水中检出的抗生素种类相对较多,分别为10种和8种,溶潭水和土壤中则检出的抗生素种类较少.因子分析结果显示,会仙湿地水体中的典型抗生素来源可归为两类,一类以受外源污染为主,从而导致地表河水中磺胺氯达嗪(SCP)、磺胺嘧啶(SDZ)、磺胺甲恶唑(SMZ)、诺氟沙星(NOR)、氧氟沙星(OFL)检出浓度较高,一类受湿地内养殖污染,从而造成水土介质中磺胺二甲基嘧啶(SMD)、甲氧苄氨嘧啶(TMP)和金霉素(CTC)检出.水体中检出的抗生素主要受溶解氧(DO)影响,此外,甲氧苄氨嘧啶(TMP)、恩诺沙星(ENR)和强力霉素(DOX)与NH~+_4存在一定的协同污染关系.风险评估结果表明,恩诺沙星(ENR)处于高风险的范围内,磺胺甲恶唑(SMZ)、诺氟沙星(NOR)和氧氟沙星(OFL)处于中等风险,中等风险的抗生素主要集中在地表河水中,高风险抗生素则在养殖用水中.整体来看,研究区水体中抗生素存在一定的风险.因此,针对这一现象应减少存在生态风险抗生素的使用,并对有潜在风险的抗生素加以防范.     

A prehistoric tsunami induced long-lasting ecosystem changes on a semi-arid tropical island—the case of Boka Bartol (Bonaire, Leeward Antilles)

The Caribbean is highly vulnerable to coastal hazards. Based on their short recurrence intervals over the intra-American seas, high-category tropical cyclones and their associated effects of elevated storm surge, heavy wave impacts, mudslides and floods represent the most serious threat. Given the abundance of historical accounts and trigger mechanisms (strike-slip motion and oblique collision at the northern and southern Caribbean plate boundaries, submarine and coastal landslides, volcanism), tsunamis must be considered as well. This paper presents interdisciplinary multi-proxy investigations of sediment cores (grain size distribution, carbonate content, loss-on-ignition, magnetic susceptibility, microfauna, macrofauna) from Washington-Slagbaai National Park, NW Bonaire (Leeward Antilles). No historical tsunami is recorded for this island. However, an allochthonous marine layer found in all cores at Boka Bartol reveals several sedimentary criteria typically linked with tsunami deposits. Calibrated ¹⁴C data from these cores point to a palaeotsunami with a maximum age of 3,300 years. Alternative explanations for the creation of this layer, such as inland flooding during tropical cyclones, cannot entirely be ruled out, though in recent times even the strongest of these events on Bonaire did not deposit significant amounts of sediment onshore. The setting of Boka Bartol changed from an open mangrove-fringed embayment into a poly- to hyperhaline lagoon due to the establishment or closure of a barrier of coral rubble during or subsequent to the inferred event. The timing of the event is supported by further sedimentary evidence from other lagoonal and alluvial archives on Bonaire.