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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.
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   

3.
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   

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.
In this study, Grey model (GM) and artificial neural network (ANN) were employed to predict suspended solids (SSeff) and chemical oxygen demand (CODeff) in the effluent from a wastewater treatment plant in industrial park of Taiwan. When constructing model or predicting, the influent quality or online monitoring parameters were adopted as the input variables. ANN was also adopted for comparison. The results indicated that the minimum MAPEs of 16.13 and 9.85% for SSeff and CODeff could be achieved using GMs when online monitoring parameters were taken as the input variables. Although a good fitness could be achieved using ANN, they required a large quantity of data. Contrarily, GM only required a small amount of data (at least four data) and the prediction results were even better than those of ANN. Therefore, GM could be applied successfully in predicting effluent when the information was not sufficient. The results also indicated that these simple online monitoring parameters could be applied on prediction of effluent quality well.  相似文献   

6.
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   

7.
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   

8.
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   

9.
紫外光度法测定海水石油类质控指标研究   总被引:1,自引:1,他引:0  
采取问卷调查的形式对76家"近海网"成员单位海水石油类测定情况进行调查,根据调查问卷获得的数据信息,结合实验室数据,采用控制图法确定了紫外光度法测定海水石油类质控指标限值,包括萃取剂透光率、检出限、校准曲线斜率、平行样偏差等。  相似文献   

10.
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   

11.
EU legislation stipulates that GM crops have to be monitored for potential adverse environmental effects. Monitoring preferably should take place in the most exposed areas-the cultivated fields and their neighbouring environment. Current monitoring designs do not give detailed consideration to the different exposure intensities in agricultural practice. At the same time, the selection of specific, more exposed sites is difficult considering the dynamic and diversity of crop cultivation and rotation systems and their environments. We developed an approach for prioritising the monitoring of on-farm and neighbouring sites based on differing exposure levels using a minimum dataset of cultivation and land use information. Applying a Bt-maize cultivation scenario to Brandenburg, Germany, where presently no GM crops are cultivated, we systemised and categorised areas with different spatio-temporal exposure intensities including 50 m, 200 m and 1000 m buffers. These categories correspond to different suitabilities to serve as monitoring sites. Sites are prioritised using a sequential scheme. This yields an improved and objective spatial monitoring design providing detailed exposure information. This methodology is flexible and transferable to any agricultural setting, therefore enabling superior statistical comparisons between locations and regions and thus enhancing monitoring data quality.  相似文献   

12.
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   

13.
Ohio is typical among the Midwestern and Eastern United States with high levels of water pollutants, the main sources being from agriculture. In this study, we used a digital elevation model in conjunction with hydrological indices to determine the role of landscape complexity affecting the spatial and temporal variation in pollutant levels, in one of the most impaired headwater streams in Ohio. More than eighty five percent of the study area is dominated by agriculture. Spatial distribution of slope (S), altitude and wetness index along with other watershed parameters such as flow direction, flow accumulation, stream networks, flow stream orders and erosion index were used within a Geographic Information Systems framework to quantify variation in nitrate and phosphate loads to headwater streams. Stream monitoring data for nutrient loads were used to correlate the observed spatial and temporal patterns with hydrological parameters using multiple linear regressions. Results from the wetness index calculated from a digital elevation model suggested a range of 0.10–16.39, with more than 35% having values less than 4.0. A Revised Universal Soil Loss Equation (RUSLE) predicted soil loss in the range of 0.01–4.0 t/ha/yr. Nitrate nitrogen levels in the study area paralleled precipitation patterns over time, with higher nitrate levels corresponding to high precipitation. Atmospheric deposition through precipitation could explain approximately 35% of total nitrate levels observed in streams. Among the different topographic variables and hydrological indices, results from the step-wise multiple regression suggested the following best predictors, (1) elevation range and upstream flow length for nitrate, (2) flow direction and upstream flow length for ammonia-nitrogen and slope, and (3) elevation range for phosphate levels. Differences in the landscape models observed for nitrate, phosphate and ammonia-nitrogen in the surface waters were attributed partly to differences in the chemical activity and source strengths of the different forms of these nutrients through agricultural management practices. The results identify geomorphologic and landscape characteristics that influence pollutant levels in the study area.  相似文献   

14.
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   

15.
洋河下游农灌区农作物受灾与水质污染的关系   总被引:4,自引:0,他引:4  
根据情况调查设计严密而合乎逻辑的监测方案:在农灌水质标准缺乏的情况下,根据监测数据和有关资料找出致害污染物;对本次监测数据和历年常规监测数据进行分析,确定污染源;最后提出防治污染的对策。结论是致死污染物为阿特拉津和乙草胺.而高锰酸盐指数、pH和悬浮物的超标是致害的重要有关因素;致害污染物主要来源了宣化区废水;严格监控农药厂废水、兴建污水处理厂和改善农灌措施是防治污染的途径。后来的事实完全证实了本结论和对策的正确性。  相似文献   

16.
研究了用流动注射分析技术测定水体中高锰酸盐指数。使用新发明的耐腐蚀恒流泵、低记忆高效混合器、不存留气泡流通池等部件,通过高温高压,缩短消解时间,从而建立了一种可用于无人值守的自动在线快速监测水体中高锰酸盐指数的分析方法。  相似文献   

17.
Biomarkers in fish can be a useful tool for environmental monitoring of aquatic ecosystems when diffuse pollution is becoming more important and new chemicals are being created continuously. There are, however, a number of drawbacks with this method. Because of environmental variability, health status of wild fish populations may differ between years, leading to unrepresentative results in long term studies. Furthermore, genetic or adaptive differences between populations complicate the interpretation of studies on different sites. The use of farmed fish, placed in cages, can reduce these problems. However, experimental conditions are likely to differ between sites. For practical reasons it may, e.g., be neccesary to use different types of caging. Here, the use of net cages and flow through tanks has been compared for a number of biomarkers. Rainbow trout (Oncorhynchus mykiss) were placed in net cages and flow through tanks in the river G?ta Alv, in western Sweden, during three different periods in 2004 and 2005. No differences between types of caging were found for any biomarker. Therefore, the results suggest that net cages and flow through tanks can be used and compared in environmental monitoring using biomarkers in caged rainbow trout. However, efforts should be taken to reduce differences in experimental conditions, e.g., light intensity and feeding levels.  相似文献   

18.
A new HPLC method was developed for the simultaneous determination of aminophenol isomers by means of a mixed-mode stationary phase containing both SCX and C18 moieties. All factors influencing the separation were discussed and optimized. The chromatographic conditions for the separation of aminophenols are the stationary phase duet SCX/C18, the mobile phase of aqueous phosphate buffer (pH 4.85):methanol?=?85:15 (v/v) delivered with a flow rate of 1 mL/min and a detection at 285 nm. The method proposed was validated in terms of linearity, limits of detection and quantification, accuracy and precision. The HPLC method elaborated here was applied with good results on river water samples. In order to survey the quality of surface rivers entered in treatment plants which deliver water for Bucharest, two major rivers were included in a monitoring program which last more than 1 year.  相似文献   

19.
阐述了微波车辆检测器的基本工作原理及主要特点,选取城市主干道和一级公路对交通噪声监测中所需要的车流量数据进行仪器与人工的比对监测,结果显示,昼夜总车流量误差率在5%左右,表明该仪器适用于道路交通的车流量连续监测。  相似文献   

20.
中国土壤环境调查、评价与监测   总被引:10,自引:4,他引:6  
介绍了近半个多世纪以来中国土壤环境调查情况,对20世纪50年代、80年代全国土壤调查情况进行了描述,阐述了2006年以来全国土壤污染状况调查情况。结合土壤环境现状、土壤监测与评价存在的问题,对未来中国土壤监测规划进行了展望。提出了确定土壤环境监测国控点,构建国家土壤环境监测网,落实土壤环境例行监测的监测思路,以进一步推进土壤环境监测和保护。  相似文献   

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