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1.
基于焦作市各类挥发性有机物(VOCs)的活动水平数据,采用排放系数法,编制了焦作市2016年人为源挥发性有机物排放清单.结果表明,2016年焦作市人为源VOCs排放总量为28804.80 t,其中,工艺过程源、溶剂使用源、化石燃料燃烧源、移动源和生物质燃烧源分别占排放总量的36.19%、25.48%、14.38%、13.72%、10.23%.2016年焦作市VOCs的重点排放二级源是非金属矿物制品业、表面涂装业、道路移动源、生物质露天燃烧、工业燃烧,其排放量之和共占排放总量的72.47%.在焦作市各区县中,博爱县、孟州市、武陟县和马村区的排放量较高,4个县区的VOCs排放量均超过3000 t,其排放量之和占排放总量的54.26%.  相似文献   

2.
利用FACTSAGE软件定量计算麦秆、玉米秆和稻草3种生物质燃料在燃烧过程中PM2.5的排放情况,探究反应过程中氧含量、温度等对燃烧尾气中HF、HCl、SOx和NO排放的影响,从而确定适合生物质燃料燃烧的条件。结果表明:由于秸秆F、Cl含量较多,燃烧反应后会产生大量HCl和HF。为了控制生物质燃料中F、Cl化合物的产生,燃烧温度应控制在1 000~1 100℃;氧含量应选择正常空气氧含量,氧含量过低,燃烧尾气中会生成较多的氨及氢氧化物;氧含量过高,则会生成较多的硫氧化物和氮氧化物。  相似文献   

3.
李雁  郭昌胜  侯嵩  高建峰  徐建 《环境化学》2019,38(4):746-759
二噁英作为一类持久性有机污染物,因其具有强毒性和生物累积性而被广泛关注,为减少二噁英对生态环境造成的影响,研究环境中二噁英的来源及生成机理尤为重要.固体废物焚烧是二噁英在环境中的主要来源之一.本文综述了固体废物焚烧过程中产生二噁英的浓度水平,着重分析了不同因素对二噁英生成情况的影响,同时结合近年来量子化学在研究燃烧过程中二噁英生成机理方面的应用,系统阐述了典型二噁英前驱物燃烧生成二噁英的反应路径,并对深入研究固体废物焚烧中产生的二噁英对周边环境的危害提出了建议.  相似文献   

4.
2009年冬季乌鲁木齐大气中黑碳气溶胶观测   总被引:2,自引:0,他引:2  
黑碳气溶胶(BC)是大气气溶胶的重要组成部分,其粒径一般在0.01—1μm之间,来源于任何含碳物质的不完全燃烧.其主要来源可分为自然源和人为源两种,自然源排放如火山爆发、森林大火等具有区域性和偶然性;而人为源排放,如煤、石油等化石燃料燃烧、生物质燃烧、汽车尾气等是长期和持续的,也成为大气中BC的主要来源.有研究证实BC...  相似文献   

5.
采用紫外-可见光吸收光谱法(UV-vis)和激发-发射矩阵荧光光谱法(EEM)分析了典型生物质燃烧排放颗粒物(PM2.5)中水溶性有机物(WSOM)的光学特性.结果表明,WSOM的SUVA254、E250/E365和MAE365值分别为1.79-2.60 m2·g-1、4.56-7.65和0.66-1.17 m2·g-1,说明生物质燃烧排放PM2.5中WSOM具有较低的芳香度和分子量以及较弱的吸光能力.荧光光谱结果显示,WSOM产生荧光峰的主要范围为λExEm≈(230-250)/(335-380) nm和λExEm≈(260—290)/(330—360) nm,说明生物质燃烧排放PM2.5中WSOM主要以类蛋白荧光物质为主;腐殖化指数(HIX)、荧光指...  相似文献   

6.
上虞某铅锌矿区周边土壤植物重金属含量及其污染评价   总被引:13,自引:0,他引:13  
王莹  赵全利  胡莹  杜心  葛伟  刘文菊 《环境化学》2011,30(7):1354-1360
以浙江上虞某废弃铅锌尾矿山为中心点,调查分析了其周边不同采样点(抛荒稻田,污染稻田,林地及普通稻田)土壤和植物中重金属含量及污染状况,结果表明,尾矿山周边各采样点土壤As、Zn、Pb和Cu平均含量为328 m.gkg-1、1760 m.gkg-1、2708 m.gkg-1和287 m.gkg-1,以国家土壤环境质量三级...  相似文献   

7.
生物质燃烧释放N2O的测定及其分布   总被引:7,自引:0,他引:7  
曹美秋  庄亚辉 《环境化学》1994,13(5):395-400
本文报导了实验室规模的生物质封闭燃烧系统及稻草、玉米秸、麦杆燃烧过程中N2O排放因子的测定结果,测定结果表明:稻草、麦杆及玉米秸燃烧排气中N2O的排放因子分析是84.4g/t,27.3g/t,132g/t。用N2O-N占生物全氮的百分含量表示,稻草及玉米秸分别上0.59%,0.87%。用实验得到的N2O的排放因子计算出了生物质燃烧产生N2O在全国各省、直辖市、县的年排放量,并作出了全国年排放的分布  相似文献   

8.
危险废物焚烧设施二噁英类排放特征及周边土壤污染调查   总被引:2,自引:0,他引:2  
调查了13座不同类型的危险废物焚烧设施及二噁英类排放模式及部分设施土壤的污染水平.结果表明,排放浓度同焚烧处理量没有显著的关系.4—6氯代PCDD/Fs和7—8氯代PCDD/Fs呈现出了不同的排放特征.4—6氯代PCDF/PCDD比值为60.58±1.98(95%置信区间),较通用的总PCDF/总PCDD比值更适于描述危险废物焚烧设施二噁英排放的特征.使用PCA及聚类分析方法将设施排放模式归类为3种模式.分布模式同焚烧设施炉型、处理量以及尾气处理方式等因素相关性并不显著.2,3,4,7,8PeCDF对I-TEQ的贡献为35%—45%,并与I-TEQ具有很高的相关性.厂区土壤中二噁英浓度水平约为8—14ngI-TEQ.kg-1,周边土壤浓度为1—4ngI-TEQ.kg-1左右,均处于较低水平,调查设施周边土壤的使用目前尚无明显风险.危险废物设施对周边土壤的环境风险需要进一步评估.  相似文献   

9.
基于焚烧过程中二噁英类(PCDD/Fs)的生成机理,深入探讨生活垃圾焚烧设施二噁英类生成及排放的诸多影响因素,并依据层次分析法(AHP)原理,从焚烧设施的技术水平、运行状况、管理水平3个影响因素着手建立递阶层次结构模型.分别对模型中的各个影响因素进行定性和半定量化处理,最终实现对生活垃圾焚烧设施二噁英类生成及排放影响因...  相似文献   

10.
生物质燃烧排放大量具有光吸收能力的水溶性有机碳(Water-Soluble Organic Carbon,WSOC),对空气质量、气候变化和人体健康均有重要影响。为了研究东北地区生物质燃烧对气溶胶光吸收特性的作用,于2013年5月-2014年1月采集三江平原的PM_(2.5)样品,分析了样品中生物质燃烧指示剂(左旋葡聚糖)、有机碳(OrganicCarbon,OC)和WSOC的质量浓度,以及WSOC的光吸收强度(A_(365a))。根据左旋葡聚糖的质量浓度水平,将采样期间划分为生物质燃烧(BB)期和非生物质燃烧(NBB)期。对BB和NBB期间WSOC的光吸收强度与PM_(2.5)、OC、WSOC和左旋葡聚糖之间的相关性分别进行了分析,并计算了生物质燃烧产生的WSOC对总WSOC的质量浓度和吸光能力的贡献。结果表明,在BB期间,PM_(2.5)、WSOC和左旋葡聚糖的质量浓度是NBB期间的10倍以上,WSOC的光吸收强度也相应增高了13倍。BB与NBB期间,PM_(2.5)与A365a的相关指数(R~2)分别为0.98和0.34。BB期间左旋葡聚糖和A365a的相关指数(0.91)高于NBB期间(0.09),表明BB期间生物质燃烧对PM_(2.5)有显著贡献,且排放了大量的吸光性棕色碳。在BB期间,生物质燃烧对WSOC的贡献高达74.6%,对WSOC的光吸收强度贡献高达46.2%;而在NBB期间,生物质燃烧对WSOC的贡献为26.8%,对WSOC的的光吸收强度贡献为22.6%。因此,BB期间生物质燃烧对三江平原WSOC的质量浓度和光吸收强度都具有重要影响。  相似文献   

11.
Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación  相似文献   

12.
Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.  相似文献   

13.
Summary Two South American polyphagous leaf beetles,Diabrotica speciosa andCerotoma arcuata, selectively accumulated the bitter tasting compound 23,24-dihydrocucurbitacin D in their body after ingesting root tissues of cucurbit plants. Similarly, three Asian Cucurbitaceae-feeding specialists in the genusAulacophora were found to sequester the same compound. Cucurbitacin analogs were shown to deter feeding by a bird predator, indicating an allomonal role for these compounds in cucurbitacin-associated chrysomelid leaf beetles both of New and Old Worlds. The strong affinity to cucurbitacins, selective sequestration of the analogs and consequent protection from predators suggested an ecological adaptation mechanism developed in common among these two geographically isolated subtribes in the Luperini.  相似文献   

14.
Abstract: In East Africa fire and grazing by wild and domestic ungulates maintain savannas, and pastoralists historically set fires and herded livestock through the use of temporary corrals called bomas. In recent decades traditional pastoral practices have declined, and this may be affecting biodiversity. We investigated the effects of prescribed fires and bomas on savanna bird communities in East Africa during the first and second dry seasons of the year (respectively before and after the rains that mark the onset of breeding for most birds). We compared abundance, richness, and community composition on 9‐ha burned plots, recently abandoned bomas, and control plots in the undisturbed matrix habitat over a 3‐year period. Generally, recently burned areas and abandoned bomas attracted greater densities of birds and had different community assemblages than the surrounding matrix. The effects of disturbances were influenced by interactions between primary productivity, represented by the normalized difference vegetation index, and time. Bird densities were highest and a greater proportion of species was observed on burned plots in the months following the fires. Drought conditions equalized bird densities across treatments within 1 year, and individuals from a greater proportion of species were more commonly observed on abandoned bomas. Yearly fluctuations in abundance were less pronounced on bomas than on burns, which indicate that although fire may benefit birds in the short term, bomas may have a more‐lasting positive effect and provide resources during droughts. Several Palearctic migrants were attracted to burned plots regardless of rainfall, which indicates continued fire suppression may threaten their already‐declining populations. Most notably, the paucity of birds observed on the controls suggests that the current structure of the matrix developed as a result of fire suppression. Traditional pastoralism appears critical to the maintenance of avian diversity in these savannas.  相似文献   

15.
Abstract: The last century has seen the ascendance of a core economic model, which we will refer to as Walrasian economics. This model is driven by the psychological assumptions that humans act only in a self‐referential and narrowly rational way and that production can be described as a self‐contained circular flow between firms and households. These assumptions have critical implications for the way economics is used to inform conservation biology. Yet the Walrasian model is inconsistent with a large body of empirical evidence about actual human behavior, and it violates a number of basic physical laws. Research in behavioral science and neuroscience shows that humans are uniquely social animals and not self‐centered rational economic beings. Economic production is subject to physical laws including the laws of thermodynamics and mass balance. In addition, some contemporary economic theory, spurred by exciting new research in human behavior and a wealth of data about the negative global impact of the human economy on natural systems, is moving toward a world view that places consumption and production squarely in its behavioral and biophysical context. We argue that abandoning the straightjacket of the Walrasian core is essential to further progress in understanding the complex, coupled interactions between the human economy and the natural world. We call for a new framework for economic theory and policy that is consistent with observed human behavior, recognizes the complex and frequently irreversible interaction between human and natural systems, and directly confronts the cumulative negative effects of the human economy on the Earth's life support systems. Biophysical economics and ecological economics are two emerging economic frameworks in this movement.  相似文献   

16.
Effects of Coffee Management on Deforestation Rates and Forest Integrity   总被引:1,自引:0,他引:1  
Knowledge about how forest margins are utilized can be crucial for a general understanding of changes in forest cover, forest structure, and biodiversity across landscapes. We studied forest‐agriculture transitions in southwestern Ethiopia and hypothesized that the presence of coffee (Coffea arabica)decreases deforestation rates because of coffee's importance to local economies and its widespread occurrence in forests and forest margins. Using satellite images and elevation data, we compared changes in forest cover over 37 years (1973–2010) across elevations in 2 forest‐agriculture mosaic landscapes (1100 km2 around Bonga and 3000 km2 in Goma‐Gera). In the field in the Bonga area, we determined coffee cover and forest structure in 40 forest margins that differed in time since deforestation. Both the absolute and relative deforestation rates were lower at coffee‐growing elevations compared with at higher elevations (?10/20% vs. ?40/50% comparing relative rates at 1800 m asl and 2300–2500 m asl, respectively). Within the coffee‐growing elevation, the proportion of sites with high coffee cover (>20%) was significantly higher in stable margins (42% of sites that had been in the same location for the entire period) than in recently changed margins (0% of sites where expansion of annual crops had changed the margin). Disturbance level and forest structure did not differ between sites with 30% or 3% coffee. However, a growing body of literature on gradients of coffee management in Ethiopia reports coffee's negative effects on abundances of forest‐specialist species. Even if the presence of coffee slows down the conversion of forest to annual‐crop agriculture, there is a risk that an intensification of coffee management will still threaten forest biodiversity, including the genetic diversity of wild coffee. Conservation policy for Ethiopian forests thus needs to develop strategies that acknowledge that forests without coffee production may have higher deforestation risks than forests with coffee production and that forests with coffee production often have lower biodiversity value. Efectos de la Administración Cafetalera sobre las Tasas de Deforestación y la Integridad de los Bosques  相似文献   

17.
As drivers of terrestrial ecosystems, humans have replaced large carnivores in most areas, and human influence not only exerts striking ecological pressures on biodiversity at local scales but also has indirect effects in distant corners of the world. We suggest that the multibillion dollar cashmere industry creates economic motivations that link western fashion preferences for cashmere to land use in Central Asia. This penchant for stylish clothing, in turn, encourages herders to increase livestock production which affects persistence of over 6 endangered large mammals in these remote, arid ecosystems. We hypothesized that global trade in cashmere has strong negative effects on native large mammals of deserts and grassland where cashmere‐producing goats are raised. We used time series data, ecological snapshots of the biomass of native and domestic ungulates, and ecologically and behaviorally based fieldwork to test our hypothesis. In Mongolia increases in domestic goat production were associated with a 3‐fold increase in local profits for herders coexisting with endangered saiga (Saiga tatarica).That increasing domestic grazing pressure carries fitness consequences was inferred on the basis of an approximately 4‐fold difference in juvenile recruitment among blue sheep (Pseudois nayaur)in trans‐Himalayan India. Across 7 study areas in Mongolia, India, and China's Tibetan Plateau, native ungulate biomass is now <5% that of domestic species. Such trends suggest ecosystem degradation and decreased capacity for the persistence of native species, including at least 8 Asian endemic species: saiga, chiru (Pantholops hodgsoni), Bactrian camel (Camelus bactrianus), snow leopard(Panthera uncia), khulan(Equus hemionus), kiang (E. kiang), takhi (E. przewalski), and wild yak (Bos mutus). Our results suggest striking yet indirect and unintended actions that link trophic‐level effects to markets induced by the trade for cashmere. Globalización del Mercado de Cachemira y la Declinación de Mamíferos Mayores en Asia Central  相似文献   

18.
The high conservational value of the lichen-rich vegetation and landscape of the marine foreland Ørkenen on the isle of Anholt is treated from a Danish as well as a European perspective. The sensitivity of the lichen-rich vegetation to physical disturbance is emphasized. The impact of invasive species such asPinus mugo as well as the effect of atmospheric deposition of nutrients on the heaths at Anholt is described. Considerations related to the development of a management plan for Ørkenen are presented.  相似文献   

19.
Summary The attraction of Old World leaf beetles in the genusAulacophora to kairomones and parakairomones which are effective lures for New WorldDiabrotica andAcalymma were investigated. Beetles captured on sticky traps baited with single and multicomponent lures were no different from the control traps for two species ofAulacophora. Yellow colored traps and squash blossoms are attractive toAulacophora beetles which detect sub-microgram quantities of cucurbitacins on silica gel. Leaf feeding behavior and flight activity data are correlated with varietal preference of threeAulacophora species. The common response byDiabrotica andAulacophora to cucurbitacins reinforces the two groups' coevolutionary association with the Cucurbitaceae. The apparent lack of a common response toCucurbita blossom volatiles suggests recent evolutionary pathways are substantially different for these two groups of beetles.  相似文献   

20.
Assessing causes of population decline is critically important to management of threatened species. Stochastic patch occupancy models (SPOMs) are popular tools for examining spatial and temporal dynamics of populations when presence–absence data in multiple habitat patches are available. We developed a Bayesian Markov chain method that extends existing SPOMs by focusing on past environmental changes that may have altered occupancy patterns prior to the beginning of data collection. Using occupancy data from 3 creeks, we applied the method to assess 2 hypothesized causes of population decline—in situ die-off and residual impact of past source population loss—in the California red-legged frog. Despite having no data for the 20–30 years between the hypothetical event leading to population decline and the first data collected, we were able to discriminate among hypotheses, finding evidence that in situ die-off increased in 2 of the creeks. Although the creeks had comparable numbers of occupied segments, owing to different extinction–colonization dynamics, our model predicted an 8-fold difference in persistence probabilities of their populations to 2030. Adding a source population led to a greater predicted persistence probability than did decreasing the in situ die-off, emphasizing that reversing the deleterious impacts of a disturbance may not be the most efficient management strategy. We expect our method will be useful for studying dynamics and evaluating management strategies of many species.  相似文献   

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