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1.
云南省是我国主要的锡产地,个旧市是云南省乃至全国的锡冶炼基地,其精锡产量占全国50%以上.SO2排放是形成酸雨的主要原因,锡冶炼作为典型的"三高一资"行业,了解其SO2排放情况尤为重要.国家目前对SO2排放总量的核算主要根据国家环境保护总局编制的《主要污染物总量减排核算细则(试行)》(以下简称《细则》)进行,主要耗能产品的排放量按排污系数法核算.《细则》中未对锡冶炼行业排污系数给出明确的规定.国家环境保护总局于1995—1996年编写  相似文献   

2.
近年来随着机动车保有量的快速增长,其排放的污染物已成为区域大气污染的重要来源之一,关系到人类身体健康和社会经济发展。基于COPERT模型构建成渝城市群多年尺度的机动车污染物CO、NMVOC、NO_x、PM_(2.5)、PM_(10)、CO_2、CH_4、N_2O、NH_3和SO_2排放清单,分析其时空排放特征及主要贡献车型,在此基础上设置9种污染物减排情景,评估不同减排措施下各污染物未来年的减排效果。结果表明,成渝城市群不同机动车污染物时间变化趋势存在差异,污染物CO、NMVOC、CH_4和SO_2排放量近几年下降趋势明显,而污染物NO_x、PM_(2.5)、PM_(10)和N_2O排放却呈相反趋势,特别是CO_2和NH_3排放量在整个研究期间增长趋势明显;轻型客车为污染物CO、NMVOC、CO_2、CH_4、N_2O和NH_3的主要贡献车型,而污染物NO_x、PM_(2.5)、PM_(10)和SO_2则主要来源于重型货车与重型客车的排放;污染物空间分布主要集中在成都与重庆市城市中心区域,随着路网逐渐向外延伸,排放量逐渐变小;研究期间污染物(CO、NO_x、CO_2和NH_3)排放量与GDP表现出较好的相关性;与基准情景相比,各减排情景控制下的减排效果差异明显,实施淘汰高排放车情景对污染物NO_x、PM_(2.5)、PM_(10)和CH_4的减排效果较好,实施激进新能源车推广情景对污染物NMVOC、CO_2、N_2O和NH_3的减排效果较好,而综合所有减排措施的激进综合情景的整体减排效果则最为显著。  相似文献   

3.
我国畜禽养殖业产排污系数研究进展   总被引:5,自引:0,他引:5  
畜禽养殖业污染物排放量的核算对于环境形势判断、环境规划和环境决策制定具有重要意义,同时也是畜禽污染治理工程设计的重要基础资料。产排污系数为畜禽养殖业污染物排放量的核算提供了较为客观的方法,是环境领域重要的基础数据。笔者总结了我国近年来畜禽业产排污系数的研究状况,对我国畜禽养殖业产排污系数的发展历程、不同地区采用的测算方法和测算结果进行了系统的梳理和对比,总结了畜禽业产排污系数研究一些典型的应用和改进,并对畜禽养殖业产排污系数的研究进行展望。  相似文献   

4.
排污许可证制度是管控污染物排放的基本环境管理制度,该研究在介绍中美排污许可制度发展以及农药污染特性的基础上,分别从排污许可证管控污染物种类、发放对象、排放限值确定方法和自行监测4个方面对两国农药行业排污许可证的管理内容进行了对比梳理,发现我国现行农药行业排污许可制度可从以下几个方面进一步完善:根据农药行业的污染物排放特征,进一步扩充需要管控的污染物种类;建议区分区域环境质量达标区与未达标区,采用划分控制单元分区管理的模式进行精细化管理;建议排放限值的确定不仅考虑现行生产工艺、排放控制水平等技术要求,还需考虑与区域环境质量相联系;对于污染治理效果好的企业可以采取激励政策,实现成本-效益的双赢。  相似文献   

5.
化学需氧量是中国主要污染物总量控制指标之一。分析化学需氧量排放变化及减排形势对今后化学需氧量及其他污染物减排具有借鉴意义。在分析"十一五"期间中国化学需氧量减排趋势和水环境质量变化趋势的基础上,定量和定性地考察两者之间的关系。结果表明:"十一五"期间化学需氧量排放量呈下降趋势,但生活化学需氧量排放量比重有所上升,中西部地区排放量下降趋势比东部地区要小;化学需氧量减排目标顺利实现,其中,工业源是减排主体,东部地区对减排贡献最大;中国地表水环境质量逐步改善,高锰酸盐指数质量浓度累计下降31.9%,Ⅰ~Ⅲ类水质断面比例累计提高14.4个百分点。无论是全国尺度还是流域尺度,随着化学需氧量排放量的减少,地表水水质均出现不同程度的改善,两者表现出一定程度的正相关关系,但是部分流域存在污染物排放总量与环境质量变化不完全协同的现象。  相似文献   

6.
基于全国第一次污染普查数据,结合各类污染物的产排污系数计算了农业污染物(COD、TN和TP)的产生量、排放量和入河量,对比分析了种植业、畜禽养殖业和水产养殖业的污染物排放现状。结果表明,COD、TN和TP排放量分别在种植业、畜禽养殖业及水产养殖业污染物排放总量中所占比例存在明显的差异性,COD和TN排放量占种植业污染物排放总量的比例分别为52%和45%,COD排放量占畜禽养殖业污染物排放总量的比例达91%,COD排放量占水产养殖业污染物排放总量的比例达80%;而不同产业对COD、TN和TP排放量的贡献率也明显不同,水产养殖业和畜禽养殖业对农业COD排放量的贡献率达到80%以上,种植业对农业TN排放量的贡献率接近60%,水产养殖业对农业TP排放量的贡献率接近60%。因此,若要削减有机物,应主要从水产养殖业和畜禽养殖业着手;若要削减氮类污染物,应主要从种植业着手;若要削减磷类污染物,应主要从水产养殖业着手。通过分析研究区农业污染物排放状况,可为农业污染物的削减和控制措施的制定提供一定的参考价值。  相似文献   

7.
为了使排污收费制度更有效地促进乡镇企工业健康发展,本文根据多因子迭加收费原则、等量排污等量收费原则、最小最大原则对乡镇工业排污收费最适值进行了估算,并从对乡镇企业、社会、财政收入和农村环境保护的影响以及征收等方面探讨了该值的可行性。  相似文献   

8.
论述了英国实现污染物减排环境治理方面的成功经验和做法,其主要有健全完善的法规政策体系,强化运用环境经济手段,建立节能减排的长效机制,建立科学、成熟的战略环评体系(SEA),用最佳可行技术(BAT)防止和减少污染排放,注重公众参与促进全民减排。依据英国实现污染物减排环境治理方面的成功经验和做法,结合目前我国污染物减排工作的实际,对我国污染物减排工作提出了相应的对策与建议。  相似文献   

9.
根拐我国工业污染源排污的实际情况及工作中的经验,利用数理统计的方法,给出了不同排污状况下确定排放水污染物排放量、浓度及污水流量的平均值、最大值的方法.  相似文献   

10.
控制和削减农业污染物排放总量是国家环境保护"十二五"规划的重点工作之一,但现行的环境管理及产排污量削减与控制技术中还没有完整的农业污染减排的指标体系。该文阐述了构建农业污染减排指标体系的基本原则和方法,综合考虑不同农业生产类型污染物产排过程的特点,从种植业、畜禽养殖业和水产养殖业3个方面初步构建农业污染减排指标体系,以期为研究农业主要污染物减排核算体系的关键参数和制定减排核算技术方法提供基础性技术支持。基于当前农业污染减排实施中可能存在的问题,对指标体系的进一步完善提出了相关建议。  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.
A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.  相似文献   

14.
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   

15.
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   

16.
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.  相似文献   

17.
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.  相似文献   

18.
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   

19.
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   

20.
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   

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