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1.
According to EC regulations the deliberate release of genetically modified (GM) crops into the agro-environment needs to be accompanied by environmental monitoring to detect potential adverse effects, e.g.unacceptable levels of gene flow from GM to non-GM crops, or adverse effects on single species or species groups thus reducing biodiversity. There is, however, considerable scientific and public debate on how GM crops should be monitored with sufficient accuracy, discussing questions of potential adverse effects, agro-environmental variables or indicators to be monitored and respective detection methods; Another basic component, the appropriate number and location of monitoring sites, is hardly considered. Currently, no consistent GM crop monitoring approach combines these components systematically. This study focuses on and integrates spatial agro-environmental aspects at a landscape level in order to design monitoring networks. Based on examples of environmental variables associated with the cropping of Bt-Maize (Zea maize L.), herbicide-tolerant (HT) winter oilseed rape (Brassica napus L.), HT sugar beet (Beta vulgaris L.), and starch-modified potato (Solanum tuberosum L.), we develop a transferable framework and assessment scheme that comprises anticipated adverse environmental effects, variables to be measured and monitoring methods.These we integrate with a rule-based GIS (geographic information system) analysis, applying widely available spatial area and point information from existing environmental networks. This is used todevelop scenarios with optimised regional GM crop monitoring networks.  相似文献   

2.
Gene flow from genetically modified crops has been studied for more than 20 years, but public concern still remains. A lot of data on this matter is obtained on the territory of EU and the USA, but in the majority of countries, such experiments were never carried out. Here, we present the first study of interspecific and intraspecific hybridization of transgenic Brassica napus on the territory of Russia. The experiment was conducted using two different models of coexistence. Cross-pollination with related species was more frequent in mixed than that in separated populations. We observed maximum 4.1% of transgenic seeds in the progeny of Brassica rapa and 0.6% in the progeny of Brassica juncea. The highest intraspecific hybridization rate of 0.67% was observed in separated populations. DNA fragments, typical to both parents, were present in the genome of the hybrids. The risk of gene flow in Russia is relatively low, but it will be problematic to do environmental monitoring on such a big territory. However, instead of banning the cultivation of genetically modified crops, some new varieties with visually detectable selective traits could be designed and approved for cultivation.  相似文献   

3.
The portion-dilution model is a parametric restatement of the conventional view of animal pollination; it predicts the level of pollinator-mediated gene dispersal. In this study, the model was applied to white clover (Trifolium repens) and its most frequent pollinator, the honeybee (Apis mellifera). One of the three parameters in the portion-dilution model is the mean number of flowers a pollinator visits in one foraging bout. An alternative method to estimate this parameter was developed that was not depending on pollinator hive-seeking behaviour. The new estimation method, based on nectar collection, seems to be a good alternative, when reliable observation on visiting behaviour of pollinators is not possible. The gene flow in white clover was modelled. Where fields were assumed to be well separated, and only a low fraction of bees travelled between fields, the gene flow was estimated to be 0.7%, but subjected to large uncertainty. In a worst case scenario with adjacent fields—one with a genetically modified (GM) T. repens cultivar and the other with a conventional T. repens cultivar—and where all arriving bees were expected to transfer GM pollen, the median gene flow was modelled to be 7% with an estimated 95% percentile of 70%. The results show that the European Union threshold limit of 0.9% GM admixture for food and feed will likely be exceeded at times and especially organic farmers that do not accept GM admixture and often have clover and clover–grass fields might face challenges with admixture of GM.  相似文献   

4.
Genetically modified (GM) crops are now approved for commercial use in several world areas. In terms of commercial acreage, the majority of these products possess either herbicide tolerance or insect protection traits. Prior to commercialization, each product underwent a country specific review of environmental safety data by independent regulatory authorities. Registration was granted after review of the data allowed authorities to conclude that the risks were minimal or manageable when balanced with the benefits. As a condition of registration, insect resistance management (IRM) has been imposed for insect protected products in most countries. Other world areas have reviewed similar data packages and have not yet been able to grant registration for commercial release. Post-registration environmental monitoring of GM crops is viewed in some world areas as a means of enabling approvals by addressing uncertainty that exists with this technology. Questions such as, who should monitor and who should pay for it, how should monitoring be conducted, what information is necessary to collect and how long should a given product be monitored are yet to be answered. Monitoring methods could be general (surveys and questionnaires) or specific (scientific studies to address specific questions). Independent research currently underway in countries where GM crops are commercial involves monitoring the benefits as well as the risks of these products. Experience with other products has shown that monitoring of GM crops will be of value only if the questions are clearly defined, the methods are appropriate and the end points (data collected) are interpretable.  相似文献   

5.
环境预测中灰色模型的EXCEL解法   总被引:4,自引:0,他引:4  
张苗云  项成龙 《干旱环境监测》2001,15(3):171-172,192
提出了利用EXCEL应用软件建立GM(1,N)预测模型的建模方法,并结合实例介绍了建立河流高锰酸盐指数GM(1,3)模型的操作过程。  相似文献   

6.
Increasing nitrogen (N) immobilization and weed interference in the early phase of implementation of conservation agriculture (CA) affects crop yields. Yet, higher fertilizer and herbicide use to improve productivity influences greenhouse gase emissions and herbicide residues. These tradeoffs precipitated a need for adaptive N and integrated weed management in CA-based maize (Zea mays L.)—wheat [Triticum aestivum (L.) emend Fiori & Paol] cropping system in the Indo-Gangetic Plains (IGP) to optimize N availability and reduce weed proliferation. Adaptive N fertilization was based on soil test value and normalized difference vegetation index measurement (NDVM) by GreenSeeker? technology, while integrated weed management included brown manuring (Sesbania aculeata L. co-culture, killed at 25 days after sowing), herbicide mixture, and weedy check (control, i.e., without weed management). Results indicated that the ‘best-adaptive N rate’ (i.e., 50% basal + 25% broadcast at 25 days after sowing + supplementary N guided by NDVM) increased maize and wheat grain yields by 20 and 14% (averaged for 2 years), respectively, compared with whole recommended N applied at sowing. Weed management by brown manuring (during maize) and herbicide mixture (during wheat) resulted in 10 and 21% higher grain yields (averaged for 2 years), respectively, over the weedy check. The NDVM in-season N fertilization and brown manuring affected N2O and CO2 emissions, but resulted in improved carbon storage efficiency, while herbicide residuals in soil were significantly lower in the maize season than in wheat cropping. This study concludes that adaptive N and integrated weed management enhance synergy between agronomic productivity, fertilizer and herbicide efficiency, and greenhouse gas mitigation.  相似文献   

7.
Combination of hydroxyapatite (HAP) and potassium chloride (KCl) was used to stabilize lead and cadmium in contaminated mining soils. Pot experiments of chilli (Capsicum annuum) and rape (Brassica rapachinensis) were used to evaluate the stabilization efficiency. The results were the following: (1) the optimal combination decreased the leachable lead by 83.3 and 97.27 %, and decreased leachable cadmium by 57.82 and 35.96% for soil HF1 and soil HF2, respectively; (2) the total lead and cadmium concentrations in both plants decreased 69 and 44 %, respectively; (3) The total lead and cadmium concentrations in the edible parts of both vegetables also decreased significantly. This study reflected that potassium chloride can improve the stabilization efficiency of hydroxyapatite, and the combination of hydroxyapatite and potassium chloride can be effectively used to remediate lead and cadmium contaminated mining soil.  相似文献   

8.
In view of their crucial role in water and solute transport, enhanced monitoring of agricultural subsurface drain tile systems is important for adequate water quality management. However, existing monitoring techniques for flow and contaminant loads from tile drains are expensive and labour intensive. The aim of this study was to develop a cost-effective and simple method for monitoring loads from tile drains. The Flowcap is a modified Sutro weir (MSW) unit that can be attached to the outlet of tile drains. It is capable of registering total flow, contaminant loads and flow-averaged concentrations. The MSW builds on a modern passive sampling technique that responds to hydraulic pressure and measures average concentrations over time (days to months) for various substances. Mounting the samplers in the MSW allowed a flow-proportional part of the drainage to be sampled. Laboratory testing yielded high linear correlation between the accumulated sampler flow, q total, and accumulated drainage flow, Q total (r 2?>?0.96). The slope of these correlations was used to calculate the total drainage discharge from the sampled volume, and therefore contaminant load. A calibration of the MSW under controlled laboratory condition was needed before interpretation of the monitoring results was possible. The MSW does not require a shed, electricity, or maintenance. This enables large-scale monitoring of contaminant loads via tile drains, which can improve contaminant transport models and yield valuable information for the selection and evaluation of mitigation options to improve water quality. Results from this type of monitoring can provide data for the evaluation and optimisation of best management practices in agriculture in order to produce the highest yield without water quality and recipient surface waters being compromised.  相似文献   

9.
针对粉尘污染点源数量多、夜间偷排偷放监测难等问题,环保监测迫切需要发展新一代遥感监测技术,为环境保护提供技术支撑。激光雷达具有远距离、全天时监测的优势,可实现对污染源的客观、全天时监测。为了验证激光雷达主动遥感技术监测粉尘污染源排放的可行性,在河北省组织了一次粉尘污染源的Lidar监测实验,在进行距离校正的基础上,发展了Lidar点源污染监测指数因子方法。结果表明:烟尘排放浓度与Lidar指数因子具有较好的一致性,校正决定系数可达0.94。在稳定排污的情况下研究Lidar指数因子的限值,结果显示,将指数因子的限值设为2.3时,与在线监测的一致性可以达到99%以上。  相似文献   

10.
基于卫星数据的灰霾污染遥感监测方法及系统设计   总被引:1,自引:1,他引:0       下载免费PDF全文
以中分辨率成像光谱仪为例,建立了卫星遥感参数和空气污染指标之间的联系,提出了基于卫星遥感的气溶胶光学厚度数据获得灰霾指数和灰霾污染时空气质量指数(AQI)等级的方法和相关的监测系统设计。结合在华北地区的监测结果,可以看出卫星遥感可以较好地反映灰霾污染程度的变化,有助于发现可能的传输通道,获得宏观的灰霾空间分布状况。在研究时段内,与地面空气质量监测站相比,88%的卫星遥感监测结果误差不大于1个AQI等级,平均的AQI等级偏差为0.7级,并分析了卫星遥感与地面监测之间差异的原因。  相似文献   

11.
水质变化灰色预测方法的探讨   总被引:2,自引:0,他引:2  
本文以某地地表水高锰酸盐指数年平均浓度的变化为例,结合新近的一些研究成果,介绍GM(1,1)模型衍生出来的几种线性回归求解法。  相似文献   

12.
堰槽式明渠废水流量监测数据有效性判别技术研究   总被引:2,自引:1,他引:1  
针对缺少堰槽明渠废水流量监测数据有效性判别技术的现状,研究了计量检定期间对废水流量计的监督检查技术,设计了现场计量检定项目、流量计运行维护情况、生产工况的变化3个方面检查内容、8项检查指标,并分别提出了检查方法及检查结果的判定与处理,填补了中国废水流量自动数据有效性认定的技术空白,完善了废水流量监测的质控体系。开展的试点工作表明,该文提出废水流量计监督检查技术具有较好的实用性。  相似文献   

13.
Monitoring of impacts of floods in river valleys of dryland regions has become important with the onset and threats of desertification and is likely to become even more vital with predictions of increased effects of climate and land use change. It is also needed in order to conform to requirements of the EU Water Framework Directive. Monitoring in such regions sets particular challenges. This paper explains a system of low-cost monitoring of changes in morphology, vegetation and sediment cover in channels and valley floors of ephemerally flowing streams. It has been applied in SE Spain for 10 years and has proved very effective. In particular, the use of simple crest-stage recorders for measuring flow height and the use of real-time differential GPS for rapid and accurate survey and for relocating points have proved very valuable. Part of the monitoring is focused on the interaction of plants and channel processes. Small changes in and around vegetation associated with flow events have been detected by a combination of quadrat surveys and cross-profiling of the channel. A range of flow events has been measured over the period of monitoring, demonstrating their differing effects and the varying sensitivity and responsiveness of different sites. The sporadic occurrence of flood events in such an environment means that a strategy of monitoring several sites and of continuation over many years has great benefits.  相似文献   

14.
原子荧光法测定水中砷监测质量控制指标研究   总被引:3,自引:0,他引:3  
通过全国多家实验室测定的大量监测数据研究了原子荧光法测定水中砷的质量控制指标,并与《水和废水监测分析方法》(第4版)中的相关指标进行了比较,旨在为环境监测工作提供质量控制依据和质量控制指标。研究表明,标准样品实验室内相对偏差的控制范围为小于等于4%;浓度小于0.05 mg/L的实际样品的相对偏差小于等于10%,浓度大于等于0.05 mg/L时相对偏差小于等于5%。实验室间相对偏差的控制范围为小于等于10%。相对误差一般控制在±15%以内,加标回收率为90%~110%。  相似文献   

15.
There is little information on the indoor environment in hotels. Analysis of fungal DNA by quantitative PCR (qPCR) is a new method which can detect general and specific sequences. Dust was collected through swab sampling of door frames in 69 hotel rooms in 20 countries in Europe and Asia (2007-2009). Five sequences were detected by qPCR: total fungal DNA, Aspergillus and Penicillium DNA (Asp/Pen DNA), Aspergillus versicolor (A. versicolor DNA), Stachybotrys chartarum (S. chartarum DNA) and Streptomyces spp. (Streptomyces DNA). Associations were analysed by multiple linear regression. Total fungal DNA (GM = 1.08 × 10(8) cell equivalents m(-2); GSD = 6.36) and Asp/Pen DNA (GM = 1.79 × 10(7) cell equivalents m(-2); GSD = 10.12) were detected in all rooms. A. versicolor DNA, S. chartarum DNA and Streptomyces DNA were detected in 84%, 28% and 47% of the samples. In total, 20% of the rooms had observed dampness/mould, and 30% had odour. Low latitude (range 1.5-64.2 degrees) was a predictor of Asp/Pen DNA. Seaside location, lack of mechanical ventilation, and dampness or mould were other predictors of total fungal DNA and Asp/Pen DNA. Hotel ranking (Trip Advisor) or self-rated quality of the interior of the hotel room was a predictor of total fungal DNA, A. versicolor DNA and Streptomyces DNA. Odour was a predictor of S. chartarum DNA. In conclusion, fungal DNA in swab samples from hotel rooms was related to latitude, seaside location, ventilation, visible dampness and indoor mould growth. Hotels in tropical areas may have 10-100 times higher levels of common moulds such as Aspergillus and Penicillium species, as compared to a temperate climate zone.  相似文献   

16.
简述了国内外遥感监测平台的发展现状,基于湖南省生态环境遥感监测现状进行了分析,指出遥感监测平台存在遥感监测与评估技术缺乏、监测能力薄弱以及监测网络建设不完善等问题。从平台建设架构出发,构建了数据平台,对卫星遥感数据、地面调查/监测资料、无人机航测数据进行管理、存储、分析等;业务平台,主要围绕水、气、土壤等整个生态环境监测体系开展相应的监测和管理,还可针对重点区域,环境督察等业务进行拓展;展示平台,主要是通过各种终端设备和硬件对各类业务进行可视化。提出发射独立高分遥感卫星、深化遥感监测应用研究、加强各部门协同合作等建议,以期为湖南省生态环境遥感监测平台建设与发展提供参考。  相似文献   

17.
以北京市某典型区域作为研究对象,在收集大量相关资料与实测历史噪声数据的基础上,对研究区域内的声环境质量影响因素进行灰色关联度分析,并运用灰色理论建立GM(1,1)模型进行预测。结果表明,影响城市区域声环境质量因素从大到小的排序依次为:机动车辆﹥常住人口数量﹥平均车流量﹥地区生产总值﹥城市道路桥梁﹥基础设施投资﹥治理噪声环保投资;以研究区域内噪声污染实测历史数据建立的GM(1,1)模型精度符合要求标准,根据GM(1,1)模型预测北京市“十二五”期间声环境质量达标且有轻微下降趋势。  相似文献   

18.
Occupational exposure to benzene was measured in two gasoline marketing terminals and five major refineries in Singapore. A total of 280 workers were monitored over two years. This assessment was carried out with two primary objectives: (1) To find out the extent of occupational exposure to benzene in the petroleum industry in Singapore, (2) To identify suitable biomarkers for monitoring of low levels of benzene exposure. The exposure was measured in five different categories of petroleum and petrochemical workers, i.e., truck drivers, despatch assistant, process operators, oil movements operators and laboratory technicians. The results revealed wide variations in exposure, from 0.01 to 13.6 ppm for personal time weighted average (TWA) exposure over the whole workshift. The exposure of truck drivers appeared to be the highest, with geometric mean (GM) of 1.98 ppm (ranged from 0.25 to 13.6 ppm). The average benzene exposure for process operators was relative low with a GM of 0.04 ppm. Lowest benzene exposure was found in the laboratory technicians, with a GM of 0.02 ppm. As cigarette smoking is known to affect metabolism of benzene, data analyses on the relationships with environmental exposure were conducted only on the 190 nonsmokers. The results showed that urinary trans, trans-muconic acid (ttMA), unmetabolized benzene in urine (UBZ) and benzene in blood (BBZ) were better biomarkers for low level benzene exposure as compared to urinary phenolic metabolites in urine, such as hydroquinone, phenol and catechol.  相似文献   

19.
Firewood is the basic fuel source in rural Bolivia. A study was conducted in an Andean village of subsistence farmers to investigate human impact on wild firewood species. A total of 114 different fuel species was inventoried during fieldtrips and transect sampling. Specific data on abundance and growth height of wild firewood species were collected in thirty-six transects of 50 ×2 m2. Information on fuel uses of plants was obtained from 13 local Quechua key participants. To appraise the impact of fuel harvest, the extraction impact value (EIV) index was developed. This index takes into account local participants?? appreciation of (1) decreasing plant abundance; (2) regeneration capacity of plants; (3) impact of root harvesting; and (4) quality of firewood. Results suggest that several (sub-)woody plant species are negatively affected by firewood harvesting. We found that anthropogenic pressure, expressed as EIV, covaried with density of firewood species, which could entail higher human pressure on more abundant and/or more accessible species. The apparent negative impact of anthropogenic pressure on populations of wild fuel species is corroborated by our finding that, in addition to altitude, several anthropogenic variables (i.e. site accessibility, cultivation of exotics and burning practices) explain part of the variation in height of firewood species in the surroundings of Apillapampa.  相似文献   

20.
Revisiting the Chesapeake Bay Phytoplankton Index of Biotic Integrity   总被引:1,自引:0,他引:1  
In 2006, a phytoplankton index of biotic integrity (PIBI) was published for Chesapeake Bay Lacouture et al. (Estuaries 29(4):598–616, 2006). The PIBI was developed from data collected during the first 18 years (1985–2002) of the Chesapeake Bay Program long-term phytoplankton and water quality monitoring programs. Combinations of up to nine phytoplankton metrics were selected to characterize bay habitat health according to plankton community condition in spring and summer seasons across four salinity zones. The independent data available at the time for index validation was not sufficient to test the PIBI because they lacked critical index parameters (pheophytin and dissolved organic carbon) and reference samples for some seasons and salinity zones. An additional 8 years of monitoring data (2003–2010) are now available to validate the original index, reassess index performance and re-examine long-term trends in PIBI conditions in the Bay. The PIBI remains sensitive to changes in nutrient and light conditions. Evaluation of the PIBI results over the entire 1985–2010 time period shows no discernible trends in the overall health of Bay habitat based on phytoplankton community conditions. This lack of overall PIBI trend appears to be a combined response to declines in water clarity and improvements in dissolved inorganic nitrogen and dissolved phosphorus conditions in the bay.  相似文献   

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