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121.
The need to safely field test genetically modified organisms is a critical step in the sequence of research leading to the commercialization of biotechnology in agriculture. To address this need the United States Department of Agriculture has established the National Biological Impact Assessment Program (NBIAP) to facilitate the safe field testing of genetically modified organisms. NBIAP fosters safe field testing of genetically modified organisms through a computerized network for information exchange, facilitation of biological monitoring techniques and by providing support for research in biosafety to develop new field testing methods and better predictive models. 相似文献
122.
Shamim Aryampa Basant Maheshwari Elly N. Sabiiti Sophia Namuddu Brian Bukenya Najib L Bateganya 《环境质量管理》2023,32(3):325-334
Leachate from waste disposal sites (WDS) can significantly affect the soil physical, chemical and biological qualities, reducing soil health and agricultural productivity. However, there is a paucity of data on soil quality for understanding soil health impact due to WDS in Uganda. This study's aim was to understand, using the Kiteezi landfill site, how WDS impact soil properties. Soil samples were collected over 4 months in and around the landfill from three locations, and the soil quality data of the nearby area were used as baseline data for assessing the impact on soil due to WDS in the area. There were significant increases in the concentration of all studied parameters at the landfill except total N. The concentrations of ammonium (14.84 ± 1.76 mg/kg), nitrate (127.96 ± 18.36 mg/kg), and pH (7.8) were above the optimum levels. The levels of available P (181.4 ± 28.9 mg/kg) and exchangeable bases; K (2.23 ± 0.24 mg/kg), Na (1.17 ± 0.14 mg/kg), Mg (3.35 ± 0.3 mg/kg) and Ca (14 ± 1.1 mg/kg) cmol (+)/kg were optimal for plant growth. The calculated CEC of 20.75 cmol (+)/kg) showed that soils have a good potential to supply plant nutrients. Heavy metal levels were still below the permissible limit. Hence, the study shows that although WDS may contribute to the increase of soil fertility, they can potentially reduce the overall productivity of soil by increasing nutrient levels beyond optimum levels. 相似文献
123.
This paper draws on the example of Tyumen Province, a federal subject of the Russian Federation, to explore the role that policies play in hindering agricultural producers’ adaptation to climate change. Its objective is to contribute to a better understanding of maladaptation at the policy level. The discourse analysis method is used to explain perceptions of climate variability in Tyumen Province and its impact on agriculture. The document analysis method is used to assess agricultural policy in Tyumen Province and its implications for producers’ adaptation to climate change. The results suggest that although agricultural producers and policymakers are acutely aware both of climate variability and the resulting loss of agricultural output, provincial agricultural policy generally fails to encourage better adaptation by agricultural producers or to support their greater economic security. Instead, it primarily focuses on meeting food production targets and thus limits the producers’ own independent moves towards adaptation. The phenomenon of maladaptation at the policy level is discussed in consideration of the general public’s and the authorities’ awareness of climate change and climate variability, and the role of science in shaping this awareness. 相似文献
124.
Marianne Lefebvre Maria Espinosa Sergio Gomez y Paloma Maria Luisa Paracchini Annette Piorr Ingo Zasada 《Journal of Environmental Planning and Management》2015,58(12):2088-2112
During the last 50 years, the Common Agricultural Policy (CAP) has impacted the evolution of European agricultural landscapes by driving changes in land use and farming practices. We propose a typology characterising the scales relevant for agricultural landscapes management and argue that action is required on three scales: (1) a landscape oriented management at the farm level; (2) the coordination of land managers’ actions at the landscape level; and (3) the conservation of the diversity of agricultural landscapes in the EU. We provide evidence that until now the CAP has mainly focused on the first scale. We also illustrate how agricultural policy could encourage coordinated actions at the landscape- and EU-scales. In particular, we propose policy instruments to coordinate actions of individual land owners (e.g. collective bonus in agro-environmental contracts or support to environmental cooperatives (scale 2)). We also analyse how the recognition and transposition of the European Landscape Convention could promote trans-frontier landscape cooperation in order, not only to conserve high-quality rural landscapes, but also to ensure the conservation of the diversity of EU landscapes (scale 3). This paper provides a knowledge base to support an integrated CAP design in the direction of improved landscape management, as an important component of the EU project towards more sustainable agriculture. 相似文献
125.
Weiwei Chen Daniel Tong Shichun Zhang Mo Dan Xuelei Zhang Hongmei Zhao 《环境科学学报(英文版)》2015,38(12):133-141
This study presents the observations of PM_(10) and PM_(2.5) concentrations at an agricultural site from April to October 2012 in Dehui city,China.Ambient air was sampled by filter-based samplers and online PM monitors.The filter samples were analyzed to determine the abundance of ionic/inorganic elements,organic carbon(OC) and elemental carbon(EC).The daily PM_(10) concentrations varied significantly over the monitoring period,with an average of168 ± 63(in the range of 52-277) μg/m~3 during the land preparation/planting period(26 April-15 June),85 ± 65(36-228) μg/m~3 during the growing season(16 June-25 September),and 207 ±88(103-310) μg/m~3 during the harvest period(26 September-31 October).PM_(2.5) accounted for44%,56%and 66%of atmospheric PM_(10) during these periods,respectively.The PM_(10) diurnal variation showed a distinct peak from 16:00 to 21:00(LST) during the growing and harvesting seasons,while a gradual increase throughout the daytime until 17:00 was observed during tilling season.Mineral dust elements(Al,Ca,Fe,and Mg) dominated the PM_(10) chemical composition during the tilling season;OC,NO_3~-,SO_4~(2-) and NH_4~+ during the growing season;and carbonaceous species(i.e.,OC and EC) during the harvesting season.Our results indicate that the soil particles emitted by farm tillage and organic matter released from straw burning are the two most significant sources of PM_(10) emissions contributing to the recurring high pollution events in this region.Therefore,development of agricultural PM inventories from soil tillage and straw burning is prioritized to support air quality modeling. 相似文献
126.
<正>Introduction Cadmium is considered a human carcinogen by the International Agency for Research on Cancer(IARC,1993)and the US National Toxicology Program(NTP,1997).Cadmium contamination of food crops is a persistent issue for both the agricultural industry as well as consumers.This is an issue for agriculture because cadmium can be present in soils naturally or as a result of industrial processes and can contaminate foods that are consumed by humans.Industrial 相似文献
127.
不同预氧化剂对长江原水氯(胺)化DBPs生成潜能的影响 总被引:1,自引:1,他引:0
以取自上海市杨树浦水厂的长江原水为研究对象,对比分析了3种常见预氧化剂二氧化氯(ClO2)、高锰酸钾(KMnO4)及氯(Cl2)预氧化对削减氯化和氯胺化消毒副产物(DBPs)生成潜能的效果情况.氯化培养实验结果表明,3种预氧化剂的处理对DBPs总量的去除效果均不显著,经ClO2、Cl2及KMnO4作用后可分别削减8.4%、5.7%及3.9%,效果为ClO2>Cl2>KMnO4.对于长江原水使用氯化消毒时,采用ClO2作为预氧化剂可取得对消毒副产物较好的去除效果.氯胺化培养实验结果表明,3种预氧化剂处理对长江原水氯胺化DBPs的生成潜能影响有较大差异,经ClO2和KMnO4作用后可分别削减18.1%及4.1%,而预氯化后则增高12.3%,对于长江原水使用氯胺化消毒时,采用ClO2作为预氧化剂可取得对消毒副产物较为明显的去除效果.同时,应尽量避免使用预氯化后加氯胺化的组合,以防止在水处理过程中生成更多的DBPs而影响出水水质. 相似文献
128.
臭氧-混凝交互作用对混凝效果的影响 总被引:1,自引:1,他引:0
采用臭氧-混凝联用(臭氧与混凝剂同时投加)和预臭氧混凝(预臭氧后待水中臭氧浓度为0后再投加混凝剂)两种方式处理水样,分析其氧化、混凝效果和消毒副产物生成势(DBPFP)等的差异,研究臭氧-混凝交互作用对处理效果的影响.结果表明,联用和预臭氧混凝效果之间存在明显差异.联用工艺中臭氧与混凝剂间发生交互作用,导致混凝剂水解形态分布发生改变是影响混凝效果的重要原因.联用处理后水样的浊度高于预臭氧混凝,主要原因之一在于臭氧降低了混凝剂水解形态分布中Alb的含量;Cl-DBPFP低于预臭氧混凝出水,是混凝剂Al Cl3及其某些水解形态对臭氧具有催化氧化的作用,促进了消毒副产物前驱物的氧化降解所致.联用对MCAA和CF生成势的去除效果显著强于预臭氧混凝,其中MCAAFP分别为5.6μg·L-1和16.9μg·L-1,CFFP分别为12.5μg·L-1和24.1μg·L-1.臭氧与混凝剂交互作用显著影响混凝效果及消毒副产物的生成,是臭氧和混凝配合使用安全性研究中需要重点关注的内容.因而,相关科研和实际水处理工艺中必须明确预臭氧及混凝剂投加位点和相对次序. 相似文献
129.
The performance of different policy design strategies is a key issue in evaluating programmes for water quality improvement
under the Water Framework Directive (60/2000). This issue is emphasised by information asymmetries between regulator and agents.
Using an economic model under asymmetric information, the aim of this paper is to compare the cost-effectiveness of selected
methods of designing payments to farmers in order to reduce nitrogen pollution in agriculture. A principal-agent model is
used, based on profit functions generated through farm-level linear programming. This allows a comparison of flat rate payments
and a menu of contracts developed through mechanism design. The model is tested in an area of Emilia Romagna (Italy) in two
policy contexts: Agenda 2000 and the 2003 Common Agricultural Policy (CAP) reform. The results show that different policy
design options lead to differences in policy costs as great as 200–400%, with clear advantages for the menu of contracts.
However, different policy scenarios may strongly affect such differences. Hence, the paper calls for greater attention to
the interplay between CAP scenarios and water quality measures. 相似文献
130.
Seidel B Alm M Peters R Kördel W Schäffer A 《Environmental science and pollution research international》2006,13(2):125-130
Background Due to the bovine spongiform encephalopathy (BSE), specified risk material (SRM) as well as animal meat and bone meal (MBM)
are banned from the food and feed chain because of a possible infection with pathogenic prions (PrPSc). Nowadays, prions are
widely accepted to be responsible for TSE(transmissible spongiform encephalopathies)-caused illnesses like BSE and scrapie,
and especially for the occurrence of the new variant of CJD in humans. Presently, SRM and MBM are burnt under high temperatures
to avoid any hazards for humans, animals or the environment. The aim of this study was to evaluate a method using animal fat
separated from Category I material which includes SRM and the carcasses of TSE-infected animals, or animals suspected of being
infected with TSE, as a source for producing biodiesel by transesterification, analogous to the biodiesel process using vegetable
oil.
Methods For this purpose, animal fat was spiked with scrapie-infected hamster brain equivalents – as representative for a TSE-infected
animal – and the biodiesel manufacturing process was downscaled and performed under lab-scale conditions.
Results and Discussion The results analysed by Western blotting showed clearly that almost each single step of the process leads to a significant
reduction of the concentration of the pathogenic prion protein (PrPSc) in the main and side-products.
Conclusion The data revealed that the biodiesel production, even from material with a high concentration of pathogenic prions, can be
considered as safe.
Recommendations and Outlook The obtained results indicated that biodiesel produced from prion-contaminated fat was safe under the tested process conditions.
However, it has to be pointed out that the results cannot be generalized because a different process control using other conditions
may lead to different results and then has to be analysed independently. It is clear that the production of biodiesel from
high risk material represents a more economic usage than the combustion of such material. 相似文献