Impact of glyphosate on the Bradyrhizobium japonicum symbiosis with glyphosate-resistant transgenic soybean: a minireview

Glyphosate-resistant (GR) soybean [Glycine max (L.) Merr.] expressing an insensitive 5-enolpyruvylshikimic acid-3-phosphate synthase (EPSPS) gene has revolutionized weed control in soybean production. The soybean nitrogen fixing symbiont, Bradyrhizobium japonicum, possesses a glyphosate-sensitive enzyme and upon exposure to glyphosate accumulates shikimic acid and hydroxybenzoic acids such as protocatechuic acid (PCA), accompanied with B. japonicum growth inhibition and death at high concentrations. In a series of greenhouse and field experiments, glyphosate inhibited nodulation and nodule leghemoglobin content of GR soybean. Glyphosate accumulated in nodules of field-grown GR soybean, but its effect on nitrogenase activity of GR soybean was inconsistent in field studies. In greenhouse studies, nitrogenase activity of GR soybean following glyphosate application was transiently inhibited especially in early growth stages, with the greatest inhibition occurring under moisture stress. Studies using bacteroid preparations showed that the level of glyphosate inhibition of bacteroid nitrogenase activity was related to in vitro glyphosate sensitivity of the B. japonicum strains. These studies indicate the potential for reduced nitrogen fixation in the GR soybean system; however, yield reductions due to this reduced N2 fixation in early stages of growth have not been demonstrated.     

Impact of genetically modified crops and their management on soil microbially mediated plant nutrient transformations

One of the potential environmental effects of the recent rapid increase in the global agricultural area cultivated with transgenic crops is a change in soil microbially mediated processes and functions. Among the many essential functions of soil biota are soil organic matter decomposition, nutrient mineralization and immobilization, oxidation-reduction reactions, biological N fixation, and solubilization. However, relatively little research has examined the direct and indirect effects of transgenic crops and their management on microbially mediated nutrient transformations in soils. The objectives of this paper are to review the available literature related to the environmental effects of transgenic crops and their management on soil microbially mediated nutrient transformations, and to consider soil properties and climatic factors that may affect the impact of transgenic crops on these processes. Targeted genetic traits for improved plant nutrition include greater plant tolerance to low Fe availability in alkaline soils, enhanced acquisition of soil inorganic and organic P, and increased assimilation of soil N. Among the potential direct effects of transgenic crops and their management are changes in soil microbial activity due to differences in the amount and composition of root exudates, changes in microbial functions resulting from gene transfer from the transgenic crop, and alteration in microbial populations because of the effects of management practices for transgenic crops, such as pesticide applications, tillage, and application of inorganic and organic fertilizer sources. Possible indirect effects of transgenic crops, including changes in the fate of transgenic crop residues and alterations in land use and rates of soil erosion, deserve further study. Despite widespread public concern, no conclusive evidence has yet been presented that currently released transgenic crops, including both herbicide and pest resistant crops, are causing significant direct effects on stimulating or suppressing soil nutrient transformations in field environments. Further consideration of the effects of a wide range of soil properties, including the amount of clay and its mineralogy, pH, soil structure, and soil organic matter, and variations in climatic conditions, under which transgenic crops may be grown, is needed in evaluating the impact of transgenic crops on soil nutrient transformations. Future environmental evaluation of the impact of the diverse transgenic crops under development could lead to an improved understanding of soil biological functions and processes.     

燃煤电厂部分环境影响损益价值评估方法初探

文章以石门电厂为例 ,运用环境经济学的价值评估方法 ,就大型燃煤电厂的水和大气污染 ,对当地农业、渔业资源、城市建筑以及人体健康等造成的损失进行价值评估 ,为进一步的费用—效益分析提供了参考     

Impact of using paper mill sludge for surface-mine reclamation on runoff water quality and plant growth

Paper mills generate large amounts of solid waste consisting of fibrous cellulose, clay, and lime. Paper mill sludge (PMS) can improve reclamation of surface-coal mines where low pH and organic-carbon levels in the spoil cover material can inhibit revegetation. When applied at high rates, however, PMS may adversely impact the quality of surface runoff. Therefore, we applied PMS at 0, 224, and 672 dry Mg ha(-)(1) to 22.1 x 4.6-m plots at a recently mined site and monitored runoff for a total of 13 mo. The zero-rate plots served as controls and received standard reclamation consisting of mulching with hay and fertilization at planting. Compared to the control plots, PMS reduced runoff fourfold to sixfold and decreased erosion from 47 Mg ha(-1) to <1 Mg ha(-1). Most of the reduction occurred in the 2.5 mo before the plots were planted. Flow-weighted average dissolved oxygen concentrations in runoff from plots at the 224 and 672 Mg ha(-1) rates, however, were much lower (相似文献   

Impact of physical factors on the society and environment

In 1988 I published a paper “Electromagnetic fields—a new ecological factor” (Markov 1988). There was no internet and very few cell phones were available. It was not even fear from the hazard of the power lines. However, I want to cite the beginning of this paper: “The contemporary conditions of life put man in dependence of the complex of physical influences on the environment and in the first place—of the electromagnetic fields. The rapid development of science and technology has resulted in the introduction of many new devices and technologies in industry, agriculture, and everyday life. On the other hand, during their phylogenetic and ontogenic development, the living organisms are continuously exposed to the influence of different biotic and abiotic factors. The physical factors are included in the first group, and the entire evolution of life is connected with an adaptation to the action of these factors.” Could I repeat this statement nearly a quarter of century later? Sure, I will. The only difference would be that I will speak not only for electromagnetic fields, but for green-house effects, global warming, volcano eruption, and radiation disasters. I would also discuss the noise and vibration to which people are exposed from early days to the very end of their life traveling with private vehicles or public transport.     

传统美术面临的冲击及存在价值探索

随着科技的飞速发展,传统美术手工技艺逐渐被计算机和数字影像所取代,其实用价值已经退出了历史的舞台。但是应该看到,传统美术并非消亡,原有的那种探索、启发、冥想、创造依然在新的美术设计和艺术表现形式中发挥作用,从而体现了其存在价值。美术的概念在被一种新的艺术概念所取代,变的是称谓和形式,不变的是灵魂和精神,而这种技术的改变正是美术的未来。     

传统农业对生态环境产生的负面影响及对策

传统农业对生态环境产生负面影响 农业面源污染问题的提出及研究的意义 传统农业在发展过程中存在着很多问题,主要集中在农业生产中的面源污染。近几年,农业面源污染愈演愈烈,成为严重制约生态建设、人居环境水平提高的＂瓶颈＂之一。     

Impact of nigerian agricultural policies on crop production and the environment

Summary Nigerian efforts in agricultural development over the past three decades have failed to improve the country's economy. A review of the sector depicts a gloomy picture. Performance is reflected in environmental degradation, mounting food deficits, and decline in both gross domestic product and export earnings, while retail food prices and import bills have been increasing. These effects have further impoverished the smallholder farmers, locking them into a poverty web. The Government must seek to establish agricultural strategies which promote political stability, self reliance, public participation, sustained production and environmental security.Dr Gbadebo J. Osemeobo is a land use and conservation specialist working for the Nigerian Tropical Forestry Action Programme. He received from the University of Ibadan, Nigeria, a BSc in 1976, an MSc in 1982 and a PhD in 1985. His research interests are in rural land use, habitat/biotic preservation, and environmental conservation. He has worked in various capacities with the Federal Department of Forestry; as Head of the Zugurma Sector of Kainji Lake National Park, 1978–1980; as Head, Regional Offices of the Federal Department of Forestry in Benin and Abeokuta, 1981–1989; and as a specialist in the Tropical Forestry Action Programme from 1990 to the present time.     

Impact indices based on introduced plant species and litter: A study of paths in St. Lawrence Islands National Park,Ontario, Canada

Paths on four islands in St Lawrence Islands National Park, Ontario were investigated to determine indicators of visitor impact Decrease in occurrence of litter and increase in frequency of introduced weeds were found to be significantly related to the number of visitors/hectare/year. Species richness was related to previous use of the islands for farming and recreation, and to access points, but not to numbers of visitors Frequency of rocky outcrops and path width varied from island to island Path width was not related to intensity of use In this park the most useful index of impact is frequency of occurrence of introduced weeds     

用政策作指导以法律为依据提高环境评价质量

本文提出了环境影响评价必须用政策作指导 ,以法律为依据 ,提高环境影响评价质量的几点意见。     

浅谈如何做好建设项目环境影响评价与规划环境影响评价的联动

围绕建设项目环境影响评价和规划环境影响评价的特点,通过在评价思路、评价内容、评价方法等方面的比较,分析其差异,从而找到两者在评价时间、评价内容等方面的联动途径,以提高环境影响评价工作的效果和效率。     

社会影响评价在油气田钻井工程中的应用

本文介绍了国际石油工业环境保护协会（IPIECA）《石油天然气行业社会影响评价导则》中社会影响评价的定义、主要原则、主要内容、评价程序与方法等,并以某油气田钻井工程社会影响评价实践为例,论述了如何有效地开展油气田钻井工程社会影响评价工作。     

Impact assessment of the European biofuel directive on land use and biodiversity

This paper presents an assessment of the potential impact of the EUs biofuel directive on European land use and biodiversity. In a spatially explicit analysis, it is determined which ecologically valuable land use types are likely to be directly replaced by biofuel crops. In addition, it is determined which land use types may be indirectly replaced by biofuel crops through competition over land between biofuel and food crops. Four scenarios of land use change are analyzed for the period 2000–2030 while for each scenario two policy variants are analyzed respectively with and without implementation of the biofuel directive. The results indicate that the area of semi natural vegetation, forest and High Nature Value farmland directly replaced by biofuel crops is small in all scenarios and differs little between policy variants. The direct effects of the directive on European land use and biodiversity therefore are relatively minor. The indirect effects of the directive on European land use and biodiversity are much larger than its direct effects. The area semi natural vegetation is found to be 3–8% smaller in policy variants with the directive as compared to policy variants without the directive. In contrast, little difference is found between the policy variants with respect to the forest area. The results of this study show that the expected indirect effects of the directive on biodiversity are much greater than its direct effects. This suggests that indirect effects need to be taken explicitly into account in assessing the environmental effects of biofuel crop cultivation and designing sustainable pathways for implementing biofuel policies.     

“气候变暖”对雅砻江水资源的影响

本文引入几种统计模型探讨“气候变暖”对水资源的影响。这些模型经实测资料验证，模拟和预测效果了。在一定环境条件下，利用它们预估“气候变暖”对雅砻江未来水资源的影响，获得令人满意的成果。     

低碳试点政策对大气环境的影响及空间效应研究

考虑以低碳转型推动区域资源节约与环境友好的高质量发展,对建设人与自然和谐共生的中国式现代化具有充分现实意义。本文以三批低碳城市试点为准自然实验,基于2004—2019年中国272个城市的平衡面板数据,运用合成控制法、双重差分法和空间杜宾模型,探究低碳试点政策影响城市大气环境的作用机制及空间效应。研究发现：(1)低碳试点城市的大气环境质量较非试点城市得到提升,经稳健性检验后这一结论依然成立。(2)通过异质性分析发现,低碳试点政策对地级市和非资源城市大气环境的改善效应更为显著;相较于特大城市和小城市,大中城市更有利于放大低碳试点的政策效应。(3)机制分析发现,低碳试点政策通过减排溢出效应、绿色创新效应和外资限流效应促进试点城市大气环境质量的提升。(4)低碳试点城市的大气环境改善效应存在正向空间溢出,试点邻近城市的大气环境因此得到治理。     

日本cIDF的实施及对我国数字内容标识符的影响研究

日本cIDF是基于内容数字唯一标识符构建而成的,它能够更有效地解决版权保护和信息资源的长期利用等问题。但是我国想要构建自己的数字唯一标识符体系也需要从实际情况和需求出发,cIDF则在很大程度上为我国构建自己的数字内容唯一标识符体系提供了参考。     

锦州油田开发建设中的污染影响及控制措施浅析

油田开发建设中潜在危险因素主要有自然灾害、环境腐蚀、误操作、设备缺陷、施工及人为破坏等问题,结合锦州油田开发建设及所处周边环境的实际情况,通过对来自于钻井、修井作业及油气集输系统的油气水渗漏等相关的工艺环节进行风险评价与分析,分析了油田开发建设对大气、生态、土壤、水环境的影响,从工艺、管理等方面提出了具体污染预防控制措施,并分析了建立应急预案的重要性。     

石油化工建设项目变更环境影响评价管理

文章分析了石油化工建设项目环境影响评价文件批准后,项目发生部分变更的主要类型,探讨了项目变更环境影响评价重点工作内容。结合实例分析,提出了项目变更环境影响评价的管理要求,对此项工作有一定的指导作用。     

宅基地征收对农户就业及福利的影响——基于CHIP数据的实证分析

宅基地征收对盘活农村土地资产、缓解城乡矛盾具有重要意义。在宅基地征收过程中,宅基地征收直接影响着农户就业及福利。以CHIP数据为基础,通过Logistic、OLS、分位数等模型探究了宅基地征收对农户就业及福利的影响。结果表明:①宅基地征收促进了农户非农就业,在就业选择、就业时间、劳动力配置3个方面解放了农村劳动力。②宅基地征收提升了农户福利,失地农户家庭可支配收入、消费支出、幸福感和健康水平显著提高,尤其以高等收入/消费农户群体提升的最为显著。基于研究结果,提出政策建议:完善被宅基地征收农户再就业保障与中低等收入/消费农户群体福利保障机制;扩大宅基地征收政策宣传,提升农户自主权。