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111.
112.
为探明化肥配施有机肥对田面水氮、磷流失及水稻系统养分吸收的影响,采用田间小区试验,设置常规施肥处理(FN)、常规施肥减氮磷量20%处理(F0)、减氮磷20%+有机肥处理(F1~F4处理有机肥施用量分别为1 500、3 000、4 500和6 000 kg/hm2)共6个处理,探索化肥减量20%配施有机肥的最优组合.结果表明:不同施肥处理下,田面水中ρ(TN)、ρ(NH4+-N)均于施肥后第1天达到峰值,随后迅速下降,于第7天后逐渐趋于稳定,ρ(TN)和ρ(NH4+-N)分别维持在各自峰值的5.1%~10.9%与4.8%~9.6%,田面水中ρ(TP)的变化趋势与ρ(TN)相似;F0与F1处理均能有效降低田面水中ρ(TN)和ρ(TP).与FN处理相比,F1处理下ρ(TN)、ρ(NH4+-N)与ρ(TP)平均值分别降低了6.5%、9.1%和3.1%,该处理能够有效地降低氮、磷养分流失风险,且增施有机肥可使水稻增产0.2%~19.8%,地上部分氮、磷累积量随有机肥施用量的增加而显著增加(P < 0.05).综合水稻产量、养分吸收和田面水养分动态等指标发现,F1处理不仅能提高区域双季稻产量,还能有效控制田面水氮、磷养分浓度,降低氮、磷地表径流产生的农田面源污染风险,是针对南方双季稻田的一项"控源节流"优化施肥模式. 相似文献
113.
Kangwei Li Chao Lin Chunmei Geng Stephen White Linghong Chen Zhier Bao Xin Zhang Yanyun Zhao Lixia Han Wen Yang Merched Azzi 《环境科学学报(英文版)》2020,32(9):14-22
A new state-of-the-art indoor smog chamber facility (CAPS-ZJU) has been constructed and characterized at Zhejiang University, which is designed for chemical mechanism evaluation under well-controlled conditions. A series of characterization experiments were performed to validate the well-established experimental protocols, including temperature variation pattern, light spectrum and equivalent intensity (JNO2), injection and mixing performance, as well as gases and particle wall loss. In addition, based on some characterization experiments, the auxiliary wall mechanism has been setup and examined. Fifty chamber experiments were performed across a broad range of experimental scenarios, and we demonstrated the ability to utilize these chamber data for evaluating SAPRC chemical mechanism. It was found that the SAPRC-11 can well predict the O3 formation and NO oxidation for almost all propene runs, with 6 hr Δ(O3 – NO) model error of –3% ± 7%, while the final O3 was underestimated by ~20% for isoprene experiments. As for toluene and p-xylene experiments, it was confirmed that SAPRC-11 has significant improvement on aromatic chemistry than earlier version of SAPRC-07, although the aromatic decay rate was still underestimated to some extent. The model sensitivity test has been carried out, and the most sensitive parameters identified are the initial concentrations of reactants and the light intensity as well as HONO offgasing rate and O3 wall loss rate. All of which demonstrated that CAPS-ZJU smog chamber could derive high quality experimental data, and could provide insights on chamber studies and chemical mechanism development. 相似文献
114.
115.
Xiaoyang Yang Chunmei Geng Xuesong Sun Wen Yang Xinhua Wang Jianhua Chen 《环境科学学报(英文版)》2016,28(2):28-34
Polycyclic aromatic hydrocarbons(PAHs) are carcinogenic or mutagenic and are important toxic pollutants in the flue gas of boilers. Two industrial grade biomass boilers were selected to investigate the characteristics of particulate-bound PAHs: one biomass boiler retro-fitted from an oil boiler(BB1) and one specially designed(BB2) biomass boiler. One coal-fired boiler was also selected for comparison. By using a dilution tunnel system, particulate samples from boilers were collected and 10 PAH species were analyzed by gas chromatography–mass spectrometry(GC–MS). The total emission factors(EFs) of PAHs ranged from 0.0064 to0.0380 mg/kg, with an average of 0.0225 mg/kg, for the biomass boiler emission samples. The total PAH EFs for the tested coal-fired boiler were 1.8 times lower than the average value of the biomass boilers. The PAH diagnostic ratios for wood pellets and straw pellets were similar.The ratio of indeno(1,2,3-cd)pyrene/[indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene] for the two biomass boilers was lower than those of the reference data for other burning devices, which can probably be used as an indicator to distinguish the emission of biomass boilers from that of industrial coal-fired boilers and residential stoves. The toxic potential of the emission from wood pellet burning was higher than that from straw pellet burning, however both of them were much lower than residential stove exhausts. 相似文献
116.
在经典的DEA模型的基础上进行了修正,采用四阶段DEA模型,旨在剔除环境控制变量对效率测度结果的影响.同时,在DEA模型的基础上引入Malmquist指数分析法,以弥补DEA模型无法测度面板数据的缺陷.选取了2012年-2014年A股节能环保上市公司的面板数据,测度了样本的融资效率及三年的融资效率变化情况,结果表明:资源循环利用行业的融资效率最高,其次是环保行业,融资效率最低的是节能行业.样本企业总体的融资效率每年都在增长,但增长速度开始放缓. 相似文献
117.
着眼于辽宁省经济发展与环境问题凸显的现状,基于压力-状态-响应(P-S-R)生态安全评价模型,选取辽宁省14个城市2003年-2012年的经济、社会与环境等25个指标数据进行生态安全综合评价,对生态安全演变趋势进行分析.结果表明:十年来辽宁省城市生态安全指数呈现整体上升趋势,生态安全综合评价指数基本与生态安全指数变化趋势相似,说明辽宁省生态安全状况正逐步改善,并且总体呈现发展趋势,辽宁省的生态安全建设取得一定进展. 相似文献
118.
Yong Geng Zuoxi Liu Bing Xue Huijuan Dong Tsuyoshi Fujita Anthony Chiu 《Environmental science and pollution research international》2014,21(23):13572-13587
Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies. 相似文献
119.
摘要:当代社会,生态问题已成为全球性的问题。但早在马克思生存的时代就已经初露端倪,马克思对此进行了详细的阐述并且提出了解决途径。 相似文献
120.
Municipal solid waste management (MSWM) in China warrants particular attention as China has become the largest MSW generator in the world and the total amount of MSW it produces continues to increase. In recent years, central and local governments have made great efforts to improve MSWM in China. New regulations and policies have been issued, urban infrastructure has been improved, and commercialization and international cooperation have been encouraged. Considering these developments, an overview is necessary to analyze the current state as well as new opportunities and challenges regarding MSWM in China. This paper shows that since the late 1990s, the amount of MSW collected has been largely decoupled from economic growth and incineration has become an increasingly widespread treatment method for MSW. We identify and discuss four major challenges and barriers related to China’s MSWM, and propose an integrated management framework to improve the overall eco-efficiency of MSWM. 相似文献