全国多环芳烃年排放量估算   总被引：17，自引：3，他引：14  

许姗姗  刘文新  陶澍 《农业环境科学学报》2005,24(3):476-479

根据排放因子和相关排放活动的统计资料,估算了USEPA优先污染物清单中16种PAHs的全国年排放量。结果表明,1999年16种PAHs排放总量约为9799t,其中7种致癌性PAHs排放总量约2000t。主要排放源为家庭燃煤和炼焦,两者分别占总排放量的66.6%和30.6%。在75%置信区间上,估算结果的不确定性大致为正负一个数量级。PAHs排放谱中荧蒽、蒽、芘以及高环化合物比例显著高于北美大湖地区。  相似文献   

饲粮中性洗涤纤维/淀粉比值对荷斯坦公牛瘤胃古菌和甲烷排放量的影响     

侯路钊  王增林  孙雪丽  刘桃桃  李秋凤  曹玉凤  李建国  高艳霞  陈攀亮 《动物营养学报》2022,34(1):358-371

本试验旨在通过Illumina HiSeq测序技术和实时定量PCR研究饲粮中性洗涤纤维(NDF)/淀粉比值对荷斯坦公牛瘤胃古菌和甲烷排放量的影响.选取36头体重[(282±37)kg]相近、健康的荷斯坦奶公牛,随机分为3组,每组12头.各组分别饲喂NDF/淀粉比值为1.13(Ⅰ组)、1.38(Ⅱ组)、1.63(Ⅲ组)的...  相似文献   

Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China     

YongQing LUO  XueYong ZHAO  Olof ANDRéN  YangChun ZHU  WenDa HUANG 《干旱区科学》2014,(4):423-431

Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon（C） contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid（0.6 g C/kg dry soil） were added to soils from three biotopes（grassland, fixed dune and mobile dune） located in Naiman, Horqin Sandy Land, Inner Mongolia, China） and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration（including that from the added substrates） was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical conductivity decreased in grassland  相似文献   

淹水条件下FACE处理的水稻以及小麦秸秆的分解及产物   总被引：2，自引：0，他引：2  

LIU Juan  HAN Yong  CAI Zu-Cong 《土壤圈》2009,19(3):389-397

Winter wheat and rice straw produced under ambient and elevated CO2 in a China rice-wheat rotation free-air CO2 enrichment (FACE) experiment was mixed with a paddy soil at a rate of 10 g kg-1 (air-dried), and the mixture was incubated under flooded conditions at 25 ℃ to examine the differences in decomposition as well as the products of crop residues produced under elevated CO2. Results showed that the C/N ratio and the amount of soluble fraction in the amended rice straw grown under elevated CO2 (FR) were 9.8% and 73.1% greater, and the cellulose and lignin were 16.0% and 9.9% lesser than those of the amended rice straw grown under ambient CO2 (AR), respectively. Compared with those of the AR treatment, the CO2-C and CH4-C emissions in the FR treatment for 25 d were increased by 7.9% and 25.0%, respectively; a higher ratio of CH4 to CO2 emissions induced by straw in the FR treatment was also observed. In contrast, in the treatments with winter wheat straw, the CO2-C and CH4-C productions, the ratio of straw-induced CH4 to CO2 emissions, and the straw composition were not significantly affected by elevated CO2, except for an 8.0% decrease in total N and a 9.7% increase in C/N ratio in the wheat straw grown under elevated CO2. Correlation analysis showed that the net CO2-C and CH4-C emissions from straw and the ratio of straw-induced CH4 to CO2 emissions were all exponentially related to the amount of soluble fraction in the amended straw (P < 0.05). These indicated that under flooded conditions, the turnover and CH4 emission from crop straw incorporated into soil were dependent on the effect of elevated CO2 on straw composition, and varied with crop species. Incorporation of rice straw grown under elevated CO2 would stimulate CH4 emission from flooded rice fields, whereas winter wheat straw grown under elevated CO2 had no effect on CH4 emission.  相似文献   

北方泥炭地甲烷排放研究: 综述   总被引：7，自引：0，他引：7  

D. Y. F. LAI 《土壤圈》2009,19(4):409-421

Northern peatlands store a large amount of carbon and play a significant role in the global carbon cycle. Owing to the presence of waterlogged and anaerobic conditions, peatlands are typically a source of methane (CH₄), a very potent greenhouse gas. This paper reviews the key mechanisms of peatland CH₄ production, consumption and transport and the major environmental and biotic controls on peatland CH₄ emissions. The advantages and disadvantages of micrometeorological and chamber methods in measuring CH₄ fluxes from northern peatlands are also discussed. The magnitude of CH₄ flux varies considerably among peatland types (bogs and fens) and microtopographic locations (hummocks and hollows). Some anthropogenic activities including forestry, peat harvesting and industrial emission of sulphur dioxide can cause a reduction in CH₄ release from northern peatlands. Further research should be conducted to investigate the in fluence of plant growth forms on CH₄ flux from northern peatlands, determine the water table threshold at which plant production in peatlands enhances CH₄ release, and quantify peatland CH₄ exchange at plant community level with a higher temporal resolution using automatic chambers.  相似文献   

畜禽养殖业污染及防治对策     

李庆永  盖玉岩 《水禽世界》2009,(6)

随着改革开放和国民经济的不断发展,"菜蓝子"工程带来了人民生活水平的不断提高.遍布城郊的畜禽养殖业呈现出稳定的增长态势,成为我国新的经济增长点.  相似文献   

规模化猪场粪污处理的综合配套技术     

王朝晖 《浙江畜牧兽医》2009,34(6)

我国规模化猪场的发展已有20多年的历史.过去由于人们环保意识不强,经济能力有限,所以大部分规模化猪场都缺少完善的粪污处理系统,以致大量未处理或未完全处理的粪污等随意排放,污染周围环境,危害人体健康,影响养殖业的快速发展.  相似文献   

规模养猪的环保出路探索     

钱君  张占武 《湖南畜牧兽医》2009,(6):31-33

近年来,随着养猪业的发展和猪群规格的不断增大。猪粪、尿的排放量也在急骤增加,甚至在很多地方已经引起人们的广泛关注,因此常有相关报道见诸报端。那么如何处理养猪业中日益突显的猪粪尿处理问题,尤其是规模化养猪场内排泄的大量粪尿对环境生态造成的污染问题,便成了迫切需要解决的问题。  相似文献   

现代经济学的生态缺失     

蒋伏利 《绿色中国(综合版)》2009,(7):54-59

2009年3月5日,温家宝总理在第十一届全国人民代表大会第二次会议政府工作报告中指出,中国政府将在2008年单位国内生产总值能耗比上年下降4．59％、化学需氧量二氧化硫排放量分别减少4．42％和5．95％的基础上,坚持不懈地推动节能减排和生态环境保护工作,坚定不移走循环经济发展之路。对此,有分析人士指出,在可持续发展问题上,天降大任于中国。其显著标志是,面对日益严峻的环境污染问题中国政府不但发布了《中国应对气候变化的政策与行动》白皮书,而且,还于2009年1月正式颁布实施《循环经济促进法》。这说明,中国正在与传统经济发展模式挥手告别。  相似文献   

亚麻荠——一种低排放的生物燃料原料     

《种业导刊》2009,(9):45-45

最近,美国密歇根理工大学的研究人员对以亚麻荠为原料生产的航空燃油整个生命周期的温室气体排放进行了测定。生命周期指从种植亚麻荠到燃料燃烧排放尾气的全过程。研究结果表明,亚麻荠航空燃油是所有以农作物为生产原料的生物燃料中温室气体排放量最少的,比化石燃料的温室气体排放量减少84％。  相似文献