我国农用地土壤环境基准与标准制定研究

在分析我国现行土壤环境质量标准不足的基础上,综述了国外制定农用地土壤环境筛选值的现状,在此基础上提出我国农用地土壤环境基准制定方法学的建议以及我国农用地土壤环境标准体系的框架建议,服务于我国农用地土壤的污染预防、风险筛选和污染农用地的安全利用、修复和风险管控。     

Economics of Grassland Conversion to Cropland in the Prairie Pothole Region

Abstract: Much of the remaining grassland, particularly in North America, is privately owned, and its conversion to cultivated cropland is largely driven by economics. An understanding of why landowners convert grassland to cropland could facilitate more effective design of grassland‐conservation programs. We built an empirical model of land‐use change in the Prairie Pothole Region (north‐central United States) to estimate the probability of grassland conversion to alternative agricultural land uses, including cultivated crops. Conversion was largely driven by landscape characteristics and the economic returns of alternative uses. Our estimate of the probability of grassland conversion to cultivated crops (1.33% on average from 1979 to 1997) was higher than past estimates (0.4%). Our model also predicted that grassland‐conversion probabilities will increase if agricultural commodity prices continue to follow the trends observed from 2001 to 2006 (0.93% probability of grassland conversion to cultivated crops in 2006 to 1.5% in 2011). Thus, nearly 121 million ha (30 million acres) of grassland could be converted by 2011. Conversion probabilities, however, are spatially heterogeneous (range 0.2% to 3%), depending on characteristics of a parcel (e.g., soil quality and economic returns). Grassland parcels with relatively high‐quality land for agricultural production are more likely to be converted to cultivated crops than lower‐quality parcels and are more responsive to changes in the economic returns on alternative agricultural land uses (i.e., conversion probability increases by a larger magnitude for high‐quality parcels when economics returns to alternative uses increase). Our results suggest that grassland conservation programs could be proactively targeted toward high‐risk parcels by anticipating changes in economic returns, such as could occur if a new biofuel processing plant were to be built in an area.     

Ammonia abatement and its impact on emissions of nitrous oxide and methane—Part 2: application for Europe

Agriculture is an important source of NH₃, which contributes to acidification and eutrophication, as well as emissions of the greenhouse gases CH₄ and N₂O. Because of their common sources, emission reduction measures for one of these gases may affect emissions of others. These interrelations are often ignored in policy making. This study presents an analysis of the effects of measures to reduce NH₃ emissions on emissions of N₂O and CH₄ from agriculture in Europe. The analysis combines information from the NH₃ module of the Regional Air pollution INformation and Simulation (RAINS) model for Europe with the IPCC method for national greenhouse gas inventories. The IPCC method for estimating agricultural emissions of N₂O and CH₄ is adjusted in order to use it in combination with the RAINS database for the European agricultural sector. As an example, we applied the adjusted method to the agricultural sector in the Netherlands and found that application of several NH₃ abatement options may result in a substantial increase in N₂O emissions while the effect on CH₄ emissions is relatively small. In Part 2 of this paper we focus on the resulting emissions for all European countries for 1990 and 2010.     

Real-world emission characteristics of carbonyl compounds from agricultural machines based on a portable emission measurement system

Emissions of carbonyl compounds from agricultural machines cannot be ignored. Carbonyl compounds can cause the formation of ozone (O₃) and secondary organic aerosols, which can cause photochemical smog to form. In this study, 20 agricultural machines were tested using portable emission measurement system (PEMS) under real-world tillage processes. The exhaust gases were sampled using 2,4-dinitrophenylhydrazine cartridges, and 15 carbonyl compounds were analyzed by high-performance liquid chromatography. Carbonyl compound emission factors for agricultural machines were 51.14–3315.62 mg/(kg-fuel), and were 2.58 ± 2.05, 0.86 ± 1.07 and 0.29 ± 0.20 g/(kg-fuel) for China 0, China II and China III emission standards, respectively. Carbonyl compound emission factor for sowing seeds of China 0 agricultural machines was 3.32 ± 1.73 g/(kg-fuel). Formaldehyde, acetaldehyde and acrolein were the dominant carbonyl compounds emitted. Differences in emission standards and tillage processes impact ozone formation potential (OFP). The mean OFP was 20.15 ± 16.15 g O₃/(kg-fuel) for the China 0 emission standard. The OFP values decreased by 66.9% from China 0 to China II, and 67.4% from China II to China III. The mean OFP for sowing seeds of China 0 agricultural machines was 25.92 ± 13.84 g O₃/(kg-fuel). Between 1.75 and 24.22 times more ozone was found to be formed during sowing seeds than during other processes for China 0 and China II agricultural machines. Total carbonyl compound emissions from agricultural machines in China was 19.23 Gg in 2019. The results improve our understanding of carbonyl compound emissions from agricultural machines in China.     

Governmentality,environmental subjectivity,and urban intensification

This article delineates concepts of eco-modernisation and urban sustainability (including its associated discourses), elucidating Foucault's notion of governmentality and examining select moments of contested urban governance in the neighbourhood of Old Ottawa South, in Ottawa, Ontario, Canada. It shows how intensification – a “compact city approach” to urban sustainability – as both policy and practice, serves to both discipline and regulate by “conducting the conduct” of environmental and entrepreneurial subjects. It reveals that zoning has more explicitly become a political technology (albeit a flexible one) for achieving “highest and best use” of private property, privileging intensification projects proposed by developers, through a hierarchical exercise of state power that privileges market processes, while undermining community values and priorities.     

Agricultural recycling of treatment-plant sludge: a case study for a vegetable-processing factory

The present study evaluated the possibility of using the sludge produced by a vegetable-processing factory in agriculture. The sludge was amended with a soil mixture (i.e., a mixture of sand, soil, and manure) and was applied at 0, 165, 330, 495 and 660 t/ha to promote the growth of cucumbers. The effects of various sludge loadings on plant growth were assessed by counting plants and leaves, measuring stem lengths, and weighing the green parts and roots of the plants. We also compared heavy metal uptake by the plants for sludge loadings of 330, 495, and 660 t/ha with various recommended standards for vegetables. Our results showed that plant growth patterns were influenced to some extent by the sludge loadings. In general, the number of leaves, stem length, and dry weight of green parts exhibited a pronounced positive growth response compared with an unfertilized control, and root growth showed a lesser but still significant response at sludge loadings of 165 and 330 t/ha. The sludge application caused no significant increase in heavy metal concentrations in the leaves, though zinc (Zn) and iron (Fe) were found at elevated concentrations. However, despite the Zn and Fe accumulation, we observed no toxicity symptoms in the plants. This may be a result of cucumber's tolerance of high metal levels.     

新型农村集约化养殖业发展中环境问题及管理对策

随着人们生活水平的提高,肉、蛋、奶等畜禽食品的消费量日趋上升,极大的刺激了畜禽养殖业的发展。这一发展使畜禽养殖特点发生了如下的变化,即由过去的分散经营,饲养头数少,主要分布在农区转变成现在的集中经营,饲养头数多,分布在城市郊区或新城区。本文分析了新型农村集约化养殖业发展中的环境问题,并针对这些问题提出了新型农村集约化养殖业的管理对策。     

Inexact credibility constrained programming for environmental system management

This study proposed an inexact credibility constrained programming (ICCP) to deal with multi-formats of uncertainties in parameters and variables for an agricultural water planning system. The study system includes three subareas with different crop distributions. The redundant water in the wet season can be stored in the reservoir and utilized in the dry season. The ICCP method can reflect not only inexact uncertainties in the objective function, variables and parameters, but also fuzzy uncertainties in the right-hand side. Interval credibility levels which represent satisfaction degrees of the constraints can be analyzed. Scenario analysis is conducted to analyze possible events in wet and dry years. The resulting solutions can provide stable intervals for the objective function and decision variables with different levels of risk when violating the constraints.     

荷兰生态（有机）农业对上海农业发展的借鉴

安全高效、资源节约、环境友好型的生态农业生产技术,已成为国际农业领域研究和关注的热点;发展高效生态（有机）农业,以新的强度和效能为长三角和我国现代化农业发展作贡献,是上海社会主义新农村建设的重大战略,是上海现代农业发展的必由之路。荷兰生态（有机）农业发展提供了以下成功经验：以生态学原理指导农业生产,实现生产生态共荣;在农产品生产中应用HACCP理论,加强农业生产的过程控制和质量管理;通过制定良好农业技术规范（Eurep-GAP）,保障农业的可持续发展,保护生态环境。上海发展高效生态（有机）农业的对策建议：加强政策扶持,深化有机农业理论和技术研究,建立和规范与国际接轨的认证体系,以生态学的原理和原则指导农业生产和技术的发展。     

浙江省人地关系变化阶段特征及调整策略

经济快速发展地区工业化和城市化的加速发展对耕地的占用使这些地区的人地关系日趋紧张。从发展的角度看。若缺乏科学的人口再生产与土地调控机制。人地关系矛盾将直接制约这些区域经济的可持续发展。本文在翔实的历史资料基础上。通过对浙江省人地关系阶段变化特征的分析。认为浙江省人地关系紧张的状况有着历史延续性。接着分析了浙江省现代人地关系矛盾的焦点在于不断减少的耕地问题。探讨了经济发展与耕地变动的内在联系。认为只有遏制耕地减少的态势才能缓解浙江省人地关系日趋紧张的局面。同时对浙江省未来人地关系发展的态势进行了预测，佐证了如果不采取积极的应对措施。未来人地关系将日益恶化。最后。提出了浙江省人地关系的调整策略。试图为经济快速发展且人地关系紧张地区的土地利用管理提供一种新的路径选择。