地表水环境遥感监测关键技术与系统

介绍了地表水环境遥感监测的关键技术与系统及其典型应用,其代表性机理模型和应用示范成果主要来自于中国科学院遥感与数字地球研究所的高光谱遥感团队在最近几年中取得的一些研究进展,主要包括建立了基于改进双峰法的水体分布自动化遥感提取方法,实现了简单、高效和高精度的水体提取；提出了大型湖泊长时序水量估算方法,并以青藏高原湖区为例,重建了典型湖泊面积、水位和水量序列；发展了基于“软分类”的典型内陆水体叶绿素a浓度反演方法,构建了基于生物光学模型的高度浑浊水体悬浮物浓度遥感反演半解析方法,提高了反演方法的区域和季节适用性；构建了基于水色指数的大范围湖库营养状态和透明度遥感监测方法,实现了全球大型湖库营养状态遥感监测,以及全国大型湖库透明度遥感监测；在此基础上,开发了地表水环境遥感监测系统,提高了水环境遥感监测效率,促进了卫星遥感在水环境监测中的高精度业务化应用。     

基于响应曲面法的遗煤自燃分析与研究*

为研究高瓦斯易自燃煤层不同供风量、高抽巷抽采流量、低抽巷抽采流量3因素对采空区自燃“三带”分布影响规律，选取阳煤五矿8406工作面为研究对象，在数值模拟研究基础上，采用Design Expert软件进行Box Behnken试验设计，构建采空区氧化升温带宽度在3因素、3水平条件下的二次回归响应曲面模型，并对不同条件下采空区氧化升温带宽度进行预测与分析。结果表明:二次回归方程P值为0.001 6，预测模型显著，模型的失拟项为0.606 3，不显著，回归方程具有统计学意义；当供风量为1 500~2 000 m3/min，低抽流量为450~650 m3/min，高抽流量为100~200 m3/min时，对氧化升温带宽度一次项重要度排序为C（高抽巷抽采流量）>A（供风量）>B（低抽巷抽采流量），二次项重要度排序为AC（供风量和高抽巷抽采流量）>AB（供风量和低抽巷抽采流量）>BC（低抽巷抽采流量和高抽巷抽采流量），且AB,AC,BC之间均无交互作用。     

对氯气校正法测定高氯废水化学需氧量的方法研究

氯气校正法(HJ/T70-2001)是测定高氯废水化学需氧量的国标方法,为了减少样品测定过程带来的环境污染,研究在不改变HJ/T70-2001氧化体系及测试条件的情况下,将取样体积由20 mL减半为10 mL,试剂的使用量相应减半,对方法的检出限、相对误差、相对标准偏差等指标进行验证。结果表明,该方法的检出限符合要求,准确度较高,精密度较好,可用于高氯废水化学需氧量的测定。     

Urban wild meat consumption and trade in central Amazonia

The switch from hunting wild meat for home consumption to supplying more lucrative city markets in Amazonia can adversely affect some game species. Despite this, information on the amounts of wild meat eaten in Amazonian cities is still limited. We estimated wild meat consumption rates in 5 cities in the State of Amazonas in Brazil through 1046 door-to-door household interviews conducted from 2004 to 2012. With these data, we modeled the relationship between wild meat use and a selection of socioeconomic indices. We then scaled up our model to determine the amounts of wild meat likely to be consumed annually in the 62 urban centers in central Amazonia. A total of 80.3% of all interviewees reported consuming wild meat during an average of 29.3 (CI 11.6) days per year. Most wild meat was reported as bought in local markets (80.1%) or hunted by a family member (14.9%). Twenty-one taxa were cited as consumed, mostly mammals (71.6%), followed by reptiles (23.2%) and then birds (5.2%). The declared frequency of wild meat consumption was positively correlated with the proportion of rural population as well as with the per capita gross domestic product of the municipality (administrative divisions) where the cities were seated. We estimated that as much as 10,691 t of wild meat might be consumed annually in the 62 urban centers within central Amazonia, the equivalent of 6.49 kg per person per year. In monetary terms, this amounts to US$21.72 per person per year or US$35.1 million overall, the latter figure is comparable to fish and timber production in the region. Given this magnitude of wild meat trade in central Amazonia, it is fundamental to integrate this activity into the formal economy and actively develop policies that allow the trade of more resilient taxa and restrict trade in species sensitive to hunting.     

Inhibition of Amazon Deforestation and Fire by Parks and Indigenous Lands

Abstract:  Conservation scientists generally agree that many types of protected areas will be needed to protect tropical forests. But little is known of the comparative performance of inhabited and uninhabited reserves in slowing the most extreme form of forest disturbance: conversion to agriculture. We used satellite-based maps of land cover and fire occurrence in the Brazilian Amazon to compare the performance of large (>10,000 ha) uninhabited (parks) and inhabited (indigenous lands, extractive reserves, and national forests) reserves. Reserves significantly reduced both deforestation and fire. Deforestation was 1.7 (extractive reserves) to 20 (parks) times higher along the outside versus the inside of the reserve perimeters and fire occurrence was 4 (indigenous lands) to 9 (national forests) times higher. No strong difference in the inhibition of deforestation ( p = 0.11) or fire ( p = 0.34) was found between parks and indigenous lands. However, uninhabited reserves tended to be located away from areas of high deforestation and burning rates. In contrast, indigenous lands were often created in response to frontier expansion, and many prevented deforestation completely despite high rates of deforestation along their boundaries. The inhibitory effect of indigenous lands on deforestation was strong after centuries of contact with the national society and was not correlated with indigenous population density. Indigenous lands occupy one-fifth of the Brazilian Amazon—five times the area under protection in parks—and are currently the most important barrier to Amazon deforestation. As the protected-area network expands from 36% to 41% of the Brazilian Amazon over the coming years, the greatest challenge will be successful reserve implementation in high-risk areas of frontier expansion as indigenous lands are strengthened. This success will depend on a broad base of political support.     

RIPARIAN FOREST EFFECT ON LATERAL STREAM CHANNEL MIGRATION IN THE GLACIAL TILL PLAINS1

ABSTRACT: Dendrochronology analyses of point bar complexes were used to quantify the effects of riparian forests on local lateral migration of bends in seven streams in the glacial till plains of north central Missouri. Stream bends were paired with similar bank height, midchannel radius of curvature, soil composition, and watershed size. In each pair, one concave bank was forested and one was unforested. Stream bends with unforested concave banks had an average local migration rate three times greater than stream bends that had forested concave banks.     

颗粒活性炭对UASB处理垃圾渗滤液促进作用的研究

通过对比研究,考查了用UASB处理垃圾渗滤液时,投加颗粒活性炭对加速UASB反应器中污泥颗粒化进程、缩短启动时间、提高处理效果的影响。结果显示:启动时间缩短了近1/3,最大有机负荷提高近40%且出现了更大颗粒污泥,但COD去除效率没有明显提高。     

加压溶气气浮设备理论溶气量的计算

本文通过对加压溶气过程的分析 ,建立了理想加压溶气过程模型 ,在此基础上推导出新的理论溶气量计算公式 ,并与现有的计算公式进行了比较。     

宝钢中厚板分公司煤干燥机除尘系统风量调整技术探究

文章针对宝钢股份中厚板分公司炼铁厂煤干燥机除尘系统吸尘点冒灰,粉尘无组织排放超标的现象进行了测试分析,数据表明主要由除尘系统风量匹配不佳、吸尘点风量不合理造成。笔者通过不断调整阀门及风机档板开摩,测试调整后的风量、除尘性能、岗位粉尘浓度等参数,确定了一个合理的系统风量,不仅可以达到环境排放及职业卫生的要求,而且充分挖掘了除尘系统潜力,达到了节能降耗、经济运行的目的,同时对类似除尘系统风量匹配不佳、扬尘等问题也形成了有效的解决方案。     

Dynamic contact angle effects on gas-liquid behaviors in the cathode of proton exchange membrane fuel cell with stirred tank reactor design

Liquid water management is still a critical issue in the improvement of proton exchange membrane fuel cell (PEMFC) performance. In this work, for the first time, the liquid water behavior and transport inside the cathode of a PEMFC with a stirred tank reactor (STR) design, rather than the conventional PEMFC flow channel design, are numerically studied. The dynamic contact angle (DCA) is applied to multiple wall boundaries in the numerical model through a user-defined-function (UDF) code, i.e., STR-DCA model. Another numerical model with the static contact angle (SCA) and same operating conditions, i.e., STR-SCA model, is also developed for comparison. The volume of fluid (VOF) method is employed in the simulation to track the gas-liquid interface. The results show that the liquid water distribution and transport are significantly different between these two models, indicating the remarkable effects of DCA on the simulation results. It is also verified the capability of STR-PEMFC to reduce the liquid water flooding, showing the potential of this channel-less type fuel cell in the further development.