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改革开放以来我国粮食生产转型分析及展望 总被引:3,自引:0,他引:3
粮食生产转型是乡村生产体系演变的核心内容,以粮食生产转型研究为突破口能够清晰反映区域乡村人地关系的演化过程,为深化城乡融合发展和乡村转型发展研究提供新的视角。本文聚焦我国改革开放以来粮食生产转型历程,并尝试构建我国粮食生产转型的分析框架。研究发现,改革开放以来我国粮食生产转型呈现出“以粮为纲—农业结构调整—综合转型—城乡互动”四个差异化阶段特征。利用GL-RL模型,构建了我国粮食生产转型的分析框架。研究发现,改革开放以来我国粮食生产由Green Loop阶段演化到Red Loop阶段,粮食生产逐渐由本地生产融入到城乡生产网络,驱动粮食生产转型的扰动因素具有多时空尺度特征和跨尺度效应。城乡融合发展、乡村振兴战略、乡村人地关系协调和全球化等因素将会对未来粮食生产转型产生重要影响。此外,优化粮食生产转型与乡村转型发展的关系,将为保障粮食生产有序转型,完善乡村生产体系创造条件。 相似文献
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“可持续生产”与“清洁生产”内涵辨析 总被引:2,自引:0,他引:2
就可持续生产在可持续发展中的重要性而言,厘清可持续生产的含义并对可持续生产与清洁生产的内涵进行辨析十分必要.阐明可持续发展的确切含义,将其定义为与人、自然、社会相和谐的生产活动或方式.在此基础上,结合清洁生产含义,指出了可持续生产与清洁生产在实施层面、目标指向和内容维度三方面的区别:①清洁生产的实施层面仅局限于企业层面,而可持续生产却涉及到整个社会层面;②在生产活动对人和社会的影响方面,可持续生产的目标指向比清洁生产更为全面;③可持续生产是在“技术”、“制度”2个维度上的双向拓展,而清洁生产仅是在“技术”维度上的单维延伸. 相似文献
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论深入广泛推行清洁生产 总被引:2,自引:0,他引:2
在全面分析了国内推行清洁生产现状的基础上,根据中国的工业和资源特点,阐述了推行清洁生产的必要必,现时,从技术和管理两方面指出了中国推行清洁生产的巨大潜力,最后,有针对性地提出了深入广泛推行清洁生产的4条措施:(1)加快完善清洁生产政策,(2)深入实施清洁生产审计,(3)加强清洁生产技术的理论研究,(4)积极在中小企业中广泛推广清洁生产。 相似文献
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Wilhelm Schramm 《Journal of Cleaner Production》1997,5(4):291-300
New findings on the causes of waste and emissions, which were obtained from analysing numerous material streams in various sectors of industry, are presented in this article. It describes the implications of these findings for the vision of clean production, for formulating environmental policy concerning cleaner production targets, for the opportunities to assess to what extent the cleaner production targets have been met, and for the cleaner production assessment. A modified cleaner production assessment approach is presented, and illustrated using leather production as an example. The consequent implications for the diffusion of cleaner production are discussed. 相似文献
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不同产酸发酵菌群产氢能力的对比与分析 总被引:25,自引:5,他引:20
重点对乙醇型发酵菌群和丙酸型发酵菌群的产气及产氢能力进行了对比研究,并对发酵菌群由丙酸型演替为乙醇型过程中的产氢速率变化进行了分析.在有机负荷相同的条件下,乙醇型发酵菌群表现出较高的产氢速率和比产氢速率,最大产氢速率为14.99L/d,最大比产氢速率为3586.45mmol/(kg·d).而丙酸型发酵菌群产氢速率和比产氢速率都较低,分别为3.62L/d,196.46mmol/(kg·d)生物制氢反应器在运行中维持乙醇型发酵更有利于获得较高的氢气产量,应尽量避免丙酸型发酵的发生. 相似文献
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An assessment was made of the energy efficiency, yield performance, and labor requirements for the production of corn, wheat, potatoes, and apples using organic (without synthetic chemical fertilizers and pesticides) and conventional farming technologies. Organic corn and wheat production was 29–70% more energy efficient than conventional production. However, conventional potato and apple production was 7–93% more energy efficient than organic production. For all four crops, the labor input per unit of yield was higher for organic systems compared with conventional production. 相似文献
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玉米生产环境成本及全要素生产率的时空研究 总被引:2,自引:0,他引:2
论文在把玉米生产省(区)按生产能力划分为三类产区的基础上,纳入环境成本,系统分析了2004—2014年各地区玉米生产的环境成本全要素生产率及其分解的变化,并明确了三类产区在未来玉米产量保障中的地位和作用。研究结果表明:1)玉米生产环境成本全要素生产率呈现下降趋势,生产方式整体仍属于粗放型,同时玉米生产正转向劳动节约型和环境可持续型;2)第一主产区具有产量和环境可持续性优势,未来仍将是我国玉米供给主要产区,第二主产区和其他产区在要素管理和技术水平以及环境可持续性方面仍有待提高,能够为未来玉米需求提供更高保障。 相似文献
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Wei Fang Xuedong Zhang Panyue Zhang Jijun Wan Hongxiao Guo Dara S.M. Ghasimi Xavier Carol Morer Tao Zhang 《环境科学学报(英文版)》2020,32(1):93-111
In recent years, volatile fatty acid (VFA) production through anaerobic fermentation of sewage sludge, instead of methane production, has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery. This review first presents the effects of some essential factors that influence VFA production and composition. In the second part, we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition. Also, the effectiveness of these approaches is summarized in terms of sludge degradation, hydrolysis rate, and VFA production and composition. According to published studies, it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge. The possible reasons for the improvement of VFA production by different methods are also discussed. Finally, this review also highlights several current technical challenges and opportunities in VFA production with spectrum control, and further related research is proposed. 相似文献
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《Journal of Cleaner Production》2006,14(6-7):601-609
Cleaner production stakeholders have a strong desire for industry to consider cleaner production opportunities in their facilities and once they are assessed, to follow through on their implementation. This paper examines local and international initiatives within the Canadian stakeholder community (including government, NGOs, consultants, industry) that contribute to the initiation and implementation of cleaner production in industry. Specifically, stakeholders have consciously drafted regulatory compliance, education, co-funding incentives, and development-based cleaner production programs. As illustrated by case studies from six industries, the programs work together to create a climate favorable for implementation of cleaner production concepts and approaches. Based on the cleaner production drivers and barriers identified by research, the programs are well designed. However, as with cleaner production itself, there is always room for further improvement. Specifically: (i) regulatory compliance programs and timetables should leave room for cleaner production (versus end-of-pipe) approaches; (ii) cleaner production co-funding programs should target small and medium-sized enterprises (SME) and require them to use a multimedia approach (air, water, waste); (iii) education programs should incorporate demonstration assessments, feasibility assessments of common recommendations, and follow-up communication to foster implementation and continuous improvement; and (iv) mandated cleaner production should include absolute (i.e. waste/tonne production) rather than relative standards (i.e. X% reduction from status quo) in order to avoid penalizing historically proactive corporations. 相似文献
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鸡粪中高温厌氧甲烷发酵产气潜能与动力学特性 总被引:1,自引:0,他引:1
采用富含氮素的鸡粪为原料,包括原料鸡粪、鸡粪固相部分和鸡粪液相部分,选取以鸡粪为原料连续稳定运行超过90d的中高温厌氧反应器新鲜出料为接种污泥,在中温(35℃)和高温(55℃)条件下开展动力学和产甲烷潜能试验.采用Gompertz模型、一级动力学模型和两阶段模型对鸡粪中高温累积产甲烷量进行拟合.结果表明,鸡粪中高温甲烷发酵均呈现明显的快速产气期和慢速产气期两阶段特征,快速产气期的动力学常数K1分别为0.4174和0.2104d-1,快速产气分别在4.5和6.5d结束,快速产气量占到总产气量的69%和58%.原料鸡粪和液相部分的中温发酵动力学常数(K1)分别为0.4177和0.2330d-1,均高于高温的0.1721,0.2214d-1,发酵产气速率较快.鸡粪固相部分中温发酵的动力学常数为0.1960d-1,低于液相中温发酵的0.2330d-1和固相高温的0.2310d-1,中温条件下,水解过程是限制鸡粪甲烷发酵速率的主要因素之一.鸡粪固体和鸡粪液体高温发酵的动力学常数K分别为0.2310,0.22214d-1,鸡粪固体发酵产甲烷的速率快于液相部分,水解过程不是限制鸡粪高温发酵产甲烷速率的最主要因素.产甲烷潜能试验表明鸡粪在中温和高温下产甲烷潜能分别为212,177mL/gTS.因此,仅从发酵效率的角度考虑,鸡粪中温发酵比高温发酵的产甲烷潜能更高,产甲烷速率更快. 相似文献
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清洁生产战略与清洁生产审计 总被引:1,自引:0,他引:1
本文综述了清洁生产战略的产生及其在国内外的发展概况,介绍了如何对实施清洁生产主体的企业进行清洁生产审计,其基本思路、程序及特点,同时介绍了清洁生产在云南开展的情况。 相似文献
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基于化肥削减潜力及碳减排的小麦生产效率 总被引:1,自引:0,他引:1
基于2004~2015年中国小麦主产省份的小麦生产投入产出数据,分析了中国小麦生产的化肥削减及碳减排潜力,并利用SBM模型和ML指数分别测算了小麦生产的环境效率和环境全要素生产率.结果显示:科学施肥条件下,主产省份小麦生产的化肥削减及碳减排潜力分别为51.66%、37.41%;化肥削减及碳减排条件下,小麦生产环境效率未降低,2004~2015年间平均的小麦生产环境效率为0.970,北方地区的小麦生产环境效率要低于南方地区,小麦生产的MLEFFCH指数、MLTECH指数、ML指数超过了1,大于化肥未削减、全碳排放条件下的MLEFFCH指数、MLTECH指数、ML指数,化肥削减及碳减排利于实际生产向最大产出迫近,以达到生产的帕累托最优状态. 相似文献
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全面推进清洁生产,从源头上减少污染物的产生是推进"循环经济"的重要方略.本文回顾了我国以及湖北省开展清洁生产的概况,分析了湖北省开展清洁生产的有利条件,并在此基础上提出了完善政策法规、建立清洁生产基金、积极引导企业开展清洁生产、扶持清洁生产技术服务机构、做好部门协调及省地分工工作等加快湖北省清洁生产工作的思路与建议. 相似文献
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首先,论述了我国清洁生产的认识形成过程;接着,分析了我国清洁生产的实践及取得的成就;最后,总结出了我国清洁生产实践所得出的结论,并提出了在我国进一步推行清洁生产的几点建议。 相似文献