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1.
How City Dwellers Affect Their Resource Hinterland   总被引:1,自引:0,他引:1  
This article links databases on household consumption, industrial production, economic turnover, employment, water use, and greenhouse gas emissions into a spatially explicit model. The causal sequence starts with households demanding a certain consumer basket. This demand requires production in a complex supply-chain network of interdependent industry sectors. Even though the household may be confined to a particular geographical location, say a dwelling in a city, the industries producing the indirect inputs for the commodities that the household demands will be dispersed all over Australia and probably beyond. Industrial production represents local points of economic activity, employment, water use, and emissions that have local economic, social, and environmental impacts. The consumer basket of a typical household is followed in Australia's two largest cities—Sydney and Melbourne—along its upstream supply chains and to numerous production sites within Australia. The spatial spread is described by means of a detailed regional interindustry model. Through industry-specific emissions profiles, industrial production is then translated into local impacts. We show that annually a typical household is responsible for producing approximately 80 tonnes of greenhouse gas emissions, uses around 3 million liters of water, causes about A$140,000 to circulate in the wider economy, and provides labor worth just under three full-time employment-years. We also introduce maps that visually demonstrate how a very localized household affects the environment across an entire continent. Our model is unprecedented in its spatial and sectoral detail, at least for Australia.  相似文献   

2.
Alien gastropods have caused extensive harm to biodiversity and socioeconomic systems like agriculture and horticulture worldwide. For conservation and management purposes, information on impacts needs to be easily interpretable and comparable, and the factors that determine impacts understood. This study aimed to assess gastropods alien to South Africa to compare impact severity between species and understand how they vary between habitats and mechanisms. Furthermore, we explore the relationship between environmental and socioeconomic impacts, and both impact measures with life‐history traits. We used the Environmental Impact Classification for Alien Taxa (EICAT) and Socio‐Economic Impact Classification for Alien Taxa (SEICAT) to assess impacts of 34 gastropods alien to South Africa including evidence of impact from their entire alien range. We tested for correlations between environmental and socioeconomic impacts per species, and with fecundity and native latitude range using Kendall's tau tests. Kruskal–Wallis tests were used to compare impact magnitude among mechanisms and habitats, respectively. This study presents the first application of EICAT and SEICAT for invertebrates. There was no correlation between environmental impacts and socioeconomic impacts. Habitats did not differ regarding the severity of impacts recorded, but impacts via disease transmission were lower than other mechanisms. Neither fecundity nor native range latitude was correlated with impact magnitude. Despite gastropods being agricultural and horticultural pests globally, resilience of socioeconomic systems makes high impacts uncommon. Environmental systems may be vulnerable to gastropod impacts across habitats, having experienced multiple local extinctions of wetland island snail fauna. South Africa stands out as the only continental country that follows this trend. The knowledge gained on severity and nature of gastropod impacts is useful in risk assessment, which can aid conservation management. To make impact assessments more realistic, we suggest alternative ways of reporting impacts classified under EICAT and SEICAT.  相似文献   

3.
林柳  张立 《兽类学报》2018,38(4):411
现存的象科动物(Elephantidae)分为非洲草原象(Loxodonta africana)、非洲森林象(Loxodonta cyclotis)和亚洲象(Elephas maximus)3 种,作为森林生态系统的关键物种,它们对当地森林生态系统的影响非常复杂,在一定环境条件下,既可能是积极的作用,也可能是消极的作用。积极的作用包括:帮助植物传播种子;促进种子萌发;创造断层,维持群落多样性;为其他动物增加食物资源;为其他动物创造栖息地。消极的作用包括:使一些物种的种群数量减小;使森林变成灌木丛和草原等。而由于活动受限导致的种群密度过高是象科动物对森林生态系统产生消极作用的主要原因。当前象科动物的3 个物种均面临种群数量锐减和生存空间不断缩小的危机,为此迫切需要针对其对生物多样性和生态平衡的影响开展深入和全面的研究,并且应根据实际情况因地制宜地制定管理措施。  相似文献   

4.
The lack of spatial differentiation in current life-cycle impact assessment (LCIA) affects the relevance of the assessed impact. This article first describes a framework for constructing factors relating the region of emission to the acidifying impact on its deposition areas. Next, these factors are established for 44 European regions with the help of the RAINS model, an integrated assessment model that combines information on regional emission levels with information on long-range atmospheric transport to estimate patterns of deposition and concentration for comparison with critical loads and thresholds for acidification, eutrophication via air; and tropospheric ozone formation. The application of the acidification factors in LCIA is very straightforward. The only additional data required, the geographical site of the emission, is generally provided by current life-cycle inventory analysis. The acidification factors add resolving power of a factor of 1,000 difference between the highest and lowest ratings, while the combined uncertainties in the RAINS model are canceled out to a large extent in the acidification factors as a result of the large number of ecosystems they cover The framework presented is also suitable for establishing similar factors for eutrophication and tropospheric ozone formation for regions outside Europe as well.  相似文献   

5.
Heather Draper 《Bioethics》2019,33(8):861-871
This article sketches a taxonomy of the activities in which bioethics academics engage, including activities that may make their own research more impactful, from little or no engagement outside academia to activism or extreme activism. This taxonomy, the first of its kind, may be useful in determining what obligations bioethics academics have in relation to activism and activities that fall short of activism.  相似文献   

6.
A normalization step is widely exercised in life cycle assessment (LCA) studies in order to better understand the relative significance of impact category results. In the normalization stage, normalization references (NRs) are the characterized results of a reference system, typically a national or regional economy. Normalization is widely practiced in LCA‐based decision support and policy analysis (e.g., LCA cases in municipal solid waste treatment technologies, renewable energy technologies, and environmentally preferable purchasing programs, etc.). The compilation of NRs demands significant effort and time as well as an intimate knowledge of data availability and quality. Consequently only one set of published NRs is available for the United States, and has been adopted by various studies. In this study, the completeness of the previous NRs was evaluated and significant data gaps were identified. One of the reasons for the significant data gaps was that the toxic release inventory (TRI) data significantly underestimate the potential impact of toxic releases for some sectors. Also the previous NRs did not consider the soil emissions and nitrogen (N) and phosphorus (P) runoffs to water and chemical emissions to soils. Filling in these data gaps increased the magnitude of NRs for “human health cancer,” “human health noncancer,” “ecotoxicity,” and “eutrophication” significantly. Such significant changes can alter or even reverse the outcome of an LCA study. We applied the previous and updated NRs to conventional gasoline and corn ethanol LCAs. The results demonstrate that NRs play a decisive role in the interpretation of LCA results that use a normalization step.  相似文献   

7.
In the sediments of both of the investigated lakes, the tephra from the Mercato-Ottaviano eruption (Vesuvius, southern Italy) (ca. 7900 B.P.) could be identified. The palynological investigations show that from ca. 9000-7200 B.P. (8000-6000 cal B.C.) deciduous oak forests predominated, with only a few representatives of Mediterranean vegetation. At the transition to the central European Atlantic Period those forests changed to an open vegetation type, dominated byJuniperus andPhillyrea. At about 5500 B.P. (4400 cal B.C.), theJuniperus-Phillyrea vegetation was replaced byQuercus ilex woodland that still occurs on the island of Mljet today and is considered to be the natural vegetation of the Dalmatian coastland. The associated vegetation of theQ. ilex forests changed several times. At the beginning of theQ. ilex period,Juniperus values were still high, but soon they decreased andErica spread. In more recent times theQ. ilex forests were partially replaced by plantations ofPinus halcpensis. Indicators of human impact are sparse throughout the pollen record. Clear evidence for human influence exists only from ca. 3100 B.P. (1300 cal B.C.) whenJuglans andPinus halepensis were introduced to the area. Later,Olea andSecale cultivation can be suggested and further spreading ofJuniperus indicates use of the land as pasture.  相似文献   

8.
Measures of socio-economic impacts of conservation interventions have largely been restricted to externally defined indicators focused on income, which do not reflect people''s priorities. Using a holistic, locally grounded conceptualization of human well-being instead provides a way to understand the multi-faceted impacts of conservation on aspects of people''s lives that they value. Conservationists are engaging with well-being for both pragmatic and ethical reasons, yet current guidance on how to operationalize the concept is limited. We present nine guiding principles based around a well-being framework incorporating material, relational and subjective components, and focused on gaining knowledge needed for decision-making. The principles relate to four key components of an impact evaluation: (i) defining well-being indicators, giving primacy to the perceptions of those most impacted by interventions through qualitative research, and considering subjective well-being, which can affect engagement with conservation; (ii) attributing impacts to interventions through quasi-experimental designs, or alternative methods such as theory-based, case study and participatory approaches, depending on the setting and evidence required; (iii) understanding the processes of change including evidence of causal linkages, and consideration of trajectories of change and institutional processes; and (iv) data collection with methods selected and applied with sensitivity to research context, consideration of heterogeneity of impacts along relevant societal divisions, and conducted by evaluators with local expertise and independence from the intervention.  相似文献   

9.
Climate impact on suicide rates in Finland from 1971 to 2003   总被引:1,自引:0,他引:1  
Seasonal patterns of death from suicide are well-documented and have been attributed to climatic factors such as solar radiation and ambient temperature. However, studies on the impact of weather and climate on suicide are not consistent, and conflicting data have been reported. In this study, we performed a correlation analysis between nationwide suicide rates and weather variables in Finland during the period 1971–2003. The weather parameters studied were global solar radiation, temperature and precipitation, and a range of time spans from 1 month to 1 year were used in order to elucidate the dose-response relationship, if any, between weather variables and suicide. Single and multiple linear regression models show weak associations using 1-month and 3-month time spans, but robust associations using a 12-month time span. Cumulative global solar radiation had the best explanatory power, while average temperature and cumulative precipitation had only a minor impact on suicide rates. Our results demonstrate that winters with low global radiation may increase the risk of suicide. The best correlation found was for the 5-month period from November to March; the inter-annual variability in the cumulative global radiation for that period explained 40 % of the variation in the male suicide rate and 14 % of the variation in the female suicide rate, both at a statistically significant level. Long-term variations in global radiation may also explain, in part, the observed increasing trend in the suicide rate until 1990 and the decreasing trend since then in Finland.  相似文献   

10.
Climate change risks for net primary production of ecosystems in China   总被引:1,自引:0,他引:1  
Few studies have investigated ecosystem risk under climate change from the perspective of critical thresholds. We presented a framework to assess the climate change risk on ecosystems based on the definition of critical thresholds. Combined with climate scenario, vegetation, and soil data, the Atmosphere Vegetation Interaction Model version 2 was used to simulate net primary productivity in the period of 1961–2080. The thresholds of dangerous and unacceptable impacts were then defined, and climate change risks on ecosystems in China were assessed. Results showed that risk areas will be closely associated with future climate change and will mainly occur in the southwest and northwest areas, Inner Mongolia, the southern part of the northeast areas, and South China. The risk regions will expand to 343.66 Mha in the long term (2051–2080), accounting for 35.80% of China. The risk levels on all ecosystems (eco-regions) are likely to increase continually. The ecosystems of wooded savanna, temperate grassland, and desert grassland, which typically exhibit strong water stress, will have the maximum risk indices in the future. The Northwest Region is likely to be the most vulnerable because of precipitation restrictions and obvious warming. By contrast, Qinghai–Tibet Region will not be so vulnerable to future climate change.  相似文献   

11.
Habitat degradation through anthropogenic development is a key driver of biodiversity loss. One way to compensate losses is “biodiversity offsetting” (wherein biodiversity impacted is “replaced” through restoration elsewhere). A challenge in implementing offsets, which has received scant attention in the literature, is the accurate determination of residual biodiversity losses. We explore this challenge for offsetting gas extraction in the Ustyurt Plateau, Uzbekistan. Our goal was to determine the landscape extent of habitat impacts, particularly how the footprint of “linear” infrastructure (i.e. roads, pipelines), often disregarded in compensation calculations, compares with “hub” infrastructure (i.e. extraction facilities). We measured vegetation cover and plant species richness using the line‐intercept method, along transects running from infrastructure/control sites outward for 500 m, accounting for wind direction to identify dust deposition impacts. Findings from 24 transects were extrapolated to the broader plateau by mapping total landscape infrastructure network using GPS data and satellite imagery. Vegetation cover and species richness were significantly lower at development sites than controls. These differences disappeared within 25 m of the edge of the area physically occupied by infrastructure. The current habitat footprint of gas infrastructure is 220 ± 19 km2 across the Ustyurt (total ~ 100,000 km2), 37 ± 6% of which is linear infrastructure. Vegetation impacts diminish rapidly with increasing distance from infrastructure, and localized dust deposition does not conspicuously extend the disturbance footprint. Habitat losses from gas extraction infrastructure cover 0.2% of the study area, but this reflects directly eliminated vegetation only. Impacts upon fauna pose a more difficult determination, as these require accounting for behavioral and demographic responses to disturbance by elusive mammals, including threatened species. This study demonstrates that impacts of linear infrastructure in regions such as the Ustyurt should be accounted for not just with respect to development sites but also associated transportation and delivery routes.  相似文献   

12.
A handy impact corer for sampling of surface sediment (< 50 cm) in lakes is described. The coring apparatus consists of a sample tube, tube holder, stopper, stopper holder, shaft with wing, shaft holder, hammer, and pushing rod. The total weights are 3.8 kg (Type I: 2.3 cm inside diameter of the tube) and 6.7 kg (Type II: 5.5 cm inside diameter of the tube). The system enables confirmation of the vertical landing of the corer onto the lake bottom and effective entering of sediment into the sample tube using hammer, and prevention of falling out of the core using stopper and pushing rod.  相似文献   

13.
Traci     
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14.
We have carried out an experimental study of liquid drop impact on superhydrophobic substrates covered by a carpet ofchemically coated nano-wires.The micro-structure of the surface is similar to some biological ones(Lotus leaf for example).Inthis situation the contact angle can then be considered as equal to 180 degrees,with no hysteresis.Due to its initial inertia,thedrop experiences a flattening phase after it hits the surface,taking the shape of a pancake.Once it reaches its maximal lateralextension,the drop begins to retract and bounces back.We have extracted the lateral extension of the drop,and we propose amodel that explains the trend.We find a limit initial velocity beyond which the drop protrudes into the nano-wire carpet.Wediscuss the relevance of practical issues in terms of self-cleaning surfaces or spray-cooling.  相似文献   

15.
In field populations of the European corn borer, Ostrinia nubilalis, there is a significant inverse correlation between the prevalence of corn borer infection with the microsporidian Nosema pyrausta and the prevalence of parasitism by the introduced braconid Macrocentrus grandii where infections with N. pyrausta exceed 45%. This relationship occurs geographically and from year to year. Corn borer infection with N. pyrausta, the source of infection for M. grandii, is significantly related to corn borer density in the cornfield. These findings strongly suggest that N. pyrausta has a significant adverse affect on field populations of M. grandii and may help explain the diminishing role of this and other introduced parasites as natural controls of the corn borer in the United States.  相似文献   

16.
桃蚜被寄生龄期与受寄生蜂影响大小的关系   总被引:3,自引:0,他引:3  
刘树生 《昆虫学报》1990,33(4):430-436
在两个温度下将桃蚜Myzus perstcae无翅型不同龄期个体供菜蚜茧蜂Diaeretiella rapae产卵寄生,然后观察寄主蚜虫的发育、存活和生殖情况.结果表明,寄主蚜虫的发育速率不受影响,而从接受寄生蜂产卵到生殖率明显下降、产幼蚜终止、死亡三种症状出现的时间间隔分别为寄生蜂完成整个幼期发育所需时间的30%、40%、60%左右,这一规律不依寄主接受产卵的龄期和温度条件而变化,从而导致寄主所受影响随着接受产卵时龄期的增大而迅速下降.当蚜虫在1—2龄接受产卵时,一般不能产幼蚜,从二龄后期起,随着接受产卵龄期的推迟,所表现的内禀增长能力迅速增加,至羽化为成蚜时接受产卵,内禀增长能力已与未被寄生蚜虫的接近.由此可见,寄主不同龄期被产卵寄生的相对机率是影响蚜虫-蚜茧蜂混合种群动态关系的决定性因子之一,蚜茧蜂必须产卵于大量的1—3龄若蚜,才有可能对蚜虫种群的增长有明显的抑制作用.  相似文献   

17.
The Orangi river is an important all-year source of water for wildlife in the northern part of the Serengeti National Park. At two points along the river in the Banagi area, tributaries draining the adit and tailings of the Kilimafeza mine impact the Orangi. The former Au-Cu mine is subject to occasional wet season flooding leading to the release of iron ochres from the adit and physical as well as chemical mobilization of tailings material. The unpolluted river chemistry is essentially Na-Ca-HCO 3 and well-buffered. Drainage water; from the tailings are characterized by low pH (2.3) and high concentration of sulphate (up to 3280 mg/l), aluminium (275 mg/l), arsenic (324 mg/l), copper (125 mg/l), iron (622 mg/l), lead (21 mg/l), manganese (65 mg/l), and zinc (126 mg/l). Adit-drainage waters are typically of a lower pH (4.6) and have a lower concentration of sulphate (up to 1840 mg/l) and metals (up to 25 mg/l Al, 92 mg/l As, 42 mg/l Cu, 258 mg/l Fe, 9.6 mg/l Pb, 53 mg/l Mn, and 102 mg/l Zn). Mixing of these acidic waters with the alkaline river leads to rapid metal precipitation as Fe-ochre coatings on clastic sediment. This effect is more noticeable in the dry season. Consequently, although the tributaries draining the two sources are heavily contaminated, the effective buffering of the mine drainage waters restricts any potential pollution to within 1 km of the mine workings. Faecal coliforms show an antipathetic relationship to low pH and high metal conditions. The only mobile metals in the water outside this area are Mn and Zn and their contamination can be biologically monitored using a protozoan-based bioassay.  相似文献   

18.
中国外来海洋生物及其影响   总被引:38,自引:1,他引:38  
梁玉波  王斌 《生物多样性》2001,9(4):458-465
到目前为止,我国已从国外引进了鱼类10种、虾类2种、贝类9种、棘皮动物1种、藻类4种进行海水养殖;引进了抗盐植物2种进行盐碱地栽培;海洋水族馆业的发展,引进了数百种观赏性海洋生物;航运业中的船体附着及压舱水排放,无意中带入了几百种外来海洋生物。首先,外来海洋入侵生物与土著海洋生物争夺生存空间与食物,危害我国土著海洋生物的生存。其次,海洋外来生物通过与亲缘关系接近的物种进行杂交,降低我国海洋土著生物的遗传质量,造成遗传污染。再次,外来海洋生物可能带来病原生物,对海洋生态环境造成巨大的危害。此外,近些年来,我国沿海赤潮越来越严重,其重要原因之一是外来生存能力较强的赤潮生物的危害。  相似文献   

19.
Complete maxillary dentures are one of the most economic and easy ways of treatment for edentulous patients and are still widely used. However, their survival rate is slightly above three years. It is presumed that the failure reasons are not only due to normal fatigue but also emerge from damage based on unavoidable improper usage. Failure types other than long-term fatigue, such as over-deforming, also influence the effective life span of dentures. A hypothesis is presumed, stating that the premature/unexpected failures may be initiated by impact on dentures, which can be related to dropping them on the ground or other effects such as biting crispy food. Thus, the behavior of a complete maxillary denture under impact loading due to drop on a rigid surface was investigated using the finite element method utilizing explicit time integration and a rate-sensitive elastoplastic material model of polymethylmethacrylate (PMMA). Local permanent deformations have been observed along with an emphasis on frenulum region of the denture, regardless of the point of impact. Contact stresses at the tooth–denture base were also investigated. The spread of energy within the structure via wave propagation is seen to play a critical role in this fact. Stress-wave propagation is also seen to be an important factor that decreases the denture's fatigue life.  相似文献   

20.
This paper describes the results of a histological study of the internal organs of the plaicePleuronectes obscurus from a polluted part of Amurskii Bay, Sea of Japan. A variety of histomorphological alterations were found in the gills and liver, while the kidney and spleen were affected to a lesser degree. The most frequent lesions in gills were edemas of gill lamellae, epithelial detachments, fusions of the secondary lamellae, hypertrophies and hyperplasias of respiratory cells, pigment accumulations, the presence of parasites, increased quantities of mucous cells, lymphocyte infiltrations, and disturbances of blood circulation. Characteristic morphological changes in the liver were lipid and hydropic dystrophy, pigment accumulation, and the presence of regenerative and necrotic foci. Telangiectasia, globate filaments, and xenomas were found in the gills ofP. obscurus for the first time. These morphological alterations appear to be a result of the chronic effect of pollution in Amurskii Bay.  相似文献   

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