重庆解放碑地区环境噪声十年变化及规律

通过对解放碑商业中心区1991－2000年环境噪声监测结果的分析评价，比较了十年均噪声的时间分布污染和1998－2000年的季平均噪声的时间分布污染状况，得出该商业地区噪声污染在昼间15：00－17：00最高，夜间在4：00左右最低；四季中，秋季的昼间噪声最高，冬季的夜间的噪声最低，其昼间噪声的波动幅度也较小，与人群的社会行为活动密切相关。     

新疆诺尔特地区石炭纪火山岩的成岩机制

诺尔特地区位于阿尔泰北部山区 ,西伯利亚板块西南缘。诺尔特地区石炭纪火山岩赋存于下石炭统红山嘴组中 ,火山岩属钙碱性系列 ,主要是酸性陆相火山岩。火山岩岩浆起源于诺尔特地区中地壳位置 ,成岩物质来源于地壳。痕量元素协变关系、皮尔斯元素比值、元素丰度关系及氧同位素特征的研究表明 ,石炭纪火山岩具有明显的部分熔融成岩机制的特点 ,而结晶分异作用特点不明显 ,无混合作用特点的显示。石炭纪火山岩为部分熔融作用的产物。     

南京市城区气溶胶粒度分布特征

以九段串级式撞击采样器对南京市气溶胶进行采样测定。经统计分析发现，气溶胶呈双峰分布，粒度分布规律明显，峰值粒径在0.37μm-0.65μm和4．3μm-5.6μm之间，气溶胶浓度季节变化显著，秋季＞夏秋，秋季颗粒物中细粒子质量百分比较夏季的多，两季质量中位位直径分别为6．5μm,4,4μm，说明与季节变化密切相关。     

不同填料人工湿地处理系统的净化能力研究

研究了沸石、沸石－石灰石、石灰石3种填料的人工湿导的净化能力。结果表明：（1）沸石和石灰石混合使用，不会降低沸石吸附氨氮的能力；（2）沸石可促使难溶性P的释放，使得石灰石吸附P被植物和微生物吸收利用；（3）沸石和石灰石发生了协同作用，对TN、TP的去除效果均好于其单独使用。     

农药杀虫单的稻田流失规律研究

通过测坑、人工降雨等手段，对水溶性农药杀虫单的稻田消解动态、渗漏流失和径流流失等进行了研究。结果表明，(1)无水稻时，杀虫单在稻田水中消解的半衰期为0．76d；分蘖初期，杀虫单在稻田水中降解的半衰期为1．02d；平均为0．89d。(2)杀虫单的渗漏流失量在用药后8d内可达总用药量的7％—10％，平均为8．48％。(3)极端情况下，用药当天如果遇暴雨(50mm雨量)，杀虫单的径流流失量将达到用药量的30％左右。杀虫单的渗漏损失不可避免，故其流失控制应从径流损失着手，尽量避免在可能有暴雨的当天或雨前1—2d用药。     

土壤重金属污染及其修复技术研究

土壤重金属污染物有汞、镉、铅、锌等,主要来源于交通运输、工业污染和农业污染。土壤重金属污染会导致农作物减产甚至死亡,对人体健康也会产生极大危害。目前土壤重金属污染修复的技术主要包括工程修复法、物理化学修复法、化学修复法和生物修复法。植物修复技术作为一种新兴的绿色、生态、高效的修复技术具有良好的发展前景。     

An Estimation of the Effects of China’s Priority Forestry Programs on Farmers’ Income

In the late 1990s, the Chinese government initiated some new programs and consolidated other existing ones of ecological restoration and resource development in its forest sector, and renamed them as “Priority Forestry Programs,” or PFPs. They include the Natural Forest Protection Program (NFPP), the Sloping Land Conversion Program (SLCP), the Desertification Combating Program around Beijing and Tianjin (DCBT), the Shelterbelt Development Program (SBDP), and the Wildlife Conservation and Nature Reserve Development Program (WCNR). In addition to improving the environmental and resource conditions, a frequently reiterated goal of these PFPs is to increase rural households’ income, therefore discussing why looking at rural household income impacts might be an important part of forest program evaluation. Thus, an interesting and important question is: How has implementing the PFPs affected the farmers’ income and poverty status? This article addresses this question using a fixed-effects model and a panel dataset that covers 1968 households in four provinces for ten consecutive years (1995–2004). The empirical evidence indicates that their effects are mixed. The SLCP, the SBDP, and the NFPP have made positive impact and, by far, the SLCP has the largest effect. But the WCNR and the DCBT still have not had a pronounced overall effect due to their short time span of execution, even though they may have exerted certain influence at the margin. Notably, the impact of the WCNR, if any, is negative.     

Perennial filter strips reduce nitrate levels in soil and shallow groundwater after grassland-to-cropland conversion

Many croplands planted to perennial grasses under the Conservation Reserve Program are being returned to crop production, and with potential consequences for water quality. The objective of this study was to quantify the impact of grassland-to-cropland conversion on nitrate-nitrogen (NO3-N) concentrations in soil and shallow groundwater and to assess the potential for perennial filter strips (PFS) to mitigate increases in NO3-N levels. The study, conducted at the Neal Smith National Wildlife Refuge (NSNWR) in central Iowa, consisted of a balanced incomplete block design with 12 watersheds and four watershed-scale treatments having different proportions and topographic positions of PFS planted in native prairie grasses: 100% rowcrop, 10% PFS (toeslope position), 10% PFS (distributed on toe and as contour strips), and 20 PFS (distributed on toe and as contour strips). All treatments were established in fall 2006 on watersheds that were under bromegrass (Bromus L.) cover for at least 10 yr. Nonperennial areas were maintained under a no-till 2-yr corn (Zea mays L.)--soybean [Glycine max. (L.) Merr.] rotation since spring 2007. Suction lysimeter and shallow groundwater wells located at upslope and toeslope positions were sampled monthly during the growing season to determine NO3-N concentration from 2005 to 2008. The results indicated significant increases in NO3-N concentration in soil and groundwater following grassland-to-cropland conversion. Nitrate-nitrogen levels in the vadose zone and groundwater under PFS were lower compared with 100% cropland, with the most significant differences occurring at the toeslope position. During the years following conversion, PFS mitigated increases in subsurface nitrate, but long-term monitoring is needed to observe and understand the full response to land-use conversion.     

Characterization of a fenpropathrin-degrading strain and construction of a genetically engineered microorganism for simultaneous degradation of methyl parathion and fenpropathrin

A gram-negative fenpropathrin-degrading bacterial strain Sphingobium sp. JQL4-5 was isolated from the wastewater treatment sludge of an insecticide factory. Strain JQL4-5 showed the ability to degrade other pyrethroid insecticides, but it was not able to degrade methyl parathion. To enhance its degrading range of substrate, a methyl parathion hydrolase gene (mpd) was successfully introduced into the chromosome of strain JQL4-5 with a mini-Tn-transposon system. A genetically engineered microorganism (GEM) named JQL4-5-mpd resulted, which was capable of simultaneously degrading methyl parathion and fenpropathrin. Soil treatment results indicated that JQL4-5-mpd is a promising multifunctional bacterium in the bioremediation of multiple pesticide-contaminated environments.     

Integrated emergy,energy and economic evaluation of rice and vegetable production systems in alluvial paddy fields: Implications for agricultural policy in China

China is the largest rice producing and consuming country in the world, but rice production has given way to the production of vegetables during the past twenty years. The government has been trying to stop this land-use conversion and increase the area in rice-vegetable rotation. Important questions that must be answered to determine what strategy is best for society are, “What is the reason behind this conversion?”; “Which system is more productive and which is more sustainable?”; and “How can economic policy be used to adjust the pattern of farmland use to attain sustainable development?” To answer these questions, a combined evaluation of these agricultural production systems was done using emergy, energy and economic methods. An economic analysis clearly showed that the reason for this conversion was simply that the economic output/input ratio and the benefit density of the vegetable production system were greater than that of rice. However, both energy and emergy evaluations showed that long-term rice was the best choice for sustainable development, followed by rotation systems. The current price of rice is lower than the em-value of rice produced from the long-term rice system, but higher than that of rice produced from the rotation system. Scenario analysis showed that if the government increases the price of rice to the em-value of rice produced from the long-term rice system, US$0.4/kg, and takes the value of soil organic matter into account, the economic output/input ratios of both the rice and rotation systems will be higher than that of the vegetable system. The three methods, energy, emergy and economics, are different but complementary, each revealing a different aspect of the same system. Their combined use shows not only the reasons behind a system’s current state or condition, but also the way to adjust these systems to move toward more sustainable states.