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41.
Lara A. Roman Tenley M. Conway Theodore S. Eisenman Andrew K. Koeser Camilo Ordez Barona Dexter H. Locke G. Darrel Jenerette Johan
stberg Jess Vogt 《Ambio》2021,50(3):615
The provision of ecosystem services is a prominent rationale for urban greening, and there is a prevailing mantra that ‘trees are good’. However, understanding how urban trees contribute to sustainability must also consider disservices. In this perspective article, we discuss recent research on ecosystem disservices of urban trees, including infrastructure conflicts, health and safety impacts, aesthetic issues, and environmentally detrimental consequences, as well as management costs related to ecological disturbances and risk management. We also discuss tradeoffs regarding species selection and local conservation concerns, as well as the central role of human perception in the interpretation of ecosystem services and disservices, particularly the uncritical assertion that ‘everybody loves trees’. Urban forestry decision-making that fails to account for disservices can have unintended negative consequences for communities. Further research is needed regarding life cycle assessments, stakeholder decision-making, return-on-investment, and framings of services and disservices in urban forestry. 相似文献
42.
Bekun Festus Victor Alola Andrew Adewale Gyamfi Bright Akwasi Ampomah Asiedu Benjamin 《Environmental science and pollution research international》2021,28(47):66695-66708
Environmental Science and Pollution Research - In the energy-environment literature, a handful of the advanced economies, mostly the European Union countries, have met some of the national... 相似文献
43.
Cane rats (Thryonomyidae) are represented today by two species inhabiting sub-Saharan Africa. Their fossil record is predominately African, but includes several Miocene species from Arabia and continental Asia that represent dispersal events from Africa. For example, Paraulacodus indicus, known from the Miocene of Pakistan, is closely related to living Thryonomys. Here we describe a new thryonomyid, Protohummus dango, gen. et sp. nov., from the late Miocene Baynunah Formation of the United Arab Emirates. The new thryonomyid is less derived than “Thryonomys” asakomae from the latest Miocene of Ethiopia and clarifies the origin of crown Thryonomys and the evolutionary transition from Paraulacodus. A phylogenetic analysis shows Protohummus dango to be morphologically intermediate between Paraulacodus spp. and extinct and living Thryonomys spp. The morphological grade and phylogenetic position of Protohummus dango further supports previous biochronological estimates of the age of the Baynunah Formation (ca. 6–8 Ma). 相似文献
44.
We selected the Guanting Reservoir in Beijing, China as a case where an industrial area locates on the upwind corner to study the influence of human activities and natural processes on the distribution of polycyclic aromatic hydrocarbons (PAHs) in soils. Soil PAH concentrations in the study area follow a log-normal probability distribution function, suggesting that distribution of PAH in soils was affected by human activities. Distribution of PAHs in soils was significantly affected by the point source that high PAH concentrations were observed in near industrial area with an obvious declining trend from the northwest to the southeast which was the prevailing wind direction in this area. Away from the influence of point source, distribution of PAHs in soils was found to significantly correlate with total organic carbon content, while the influences of agricultural land uses and type of soil texture on the total soil PAHs contents and ring compositions were quite limited. The results can provide some evidences and data on the pollutant accumulation in drink water protection area influenced by natural processes and human activities. 相似文献
45.
Numair Ahmed Andrew Carlson John A. Rogers Placid M. Ferreira 《Journal of Manufacturing Processes》2012,14(2):90-97
This paper demonstrates the use of a flexible instrumented stamp to enable automated micro transfer printing as a route to large-area, deterministic assembly of microstructured device components or ‘inks’. The ability to instrument the stamp, a critical component for retrieval and placement of a micro device, to detect contact and monitor localized forces during critical events in the printing process not only allows for the development of a robust manufacturing process, but also for a unique vantage point from which to study fundamental issues and phenomena associated with adhesion and delamination of thin films from a variety of substrate materials. This paper presents basic design analysis on the requirements of the cantilevers for compatibility with a typical transfer printing environment. Off-the-shelf thin film strain gages are integrated with a thin elastomeric post as a preliminary prototype and the feasibility of transfer printing with it is demonstrated. Further, the set-up is calibrated to produce force signals for event detection and in situ diagnosis of the process. 相似文献
46.
Zhang B Cox SB McMurry ST Jackson WA Cobb GP Anderson TA 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):658-667
Soil and topical tests were employed to investigate the effect of two N-nitroso metabolites of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) on earthworm reproduction. The lowest observed effect concentration (LOEC) for cocoon production and hatching was 50mg/kg for both hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX) in soil. MNX and TNX also significantly affected cocoon hatching in soil (p<0.001) and in topical tests (p=0.001). The LOECs for cocoon hatching were 1 and 10mg/kg for MNX and TNX in soil, respectively, and 10mg/L in the topical test. Greater than 100mg/kg MNX and TNX completely inhibited cocoon hatching. In soil, the EC20 values for MNX were 8.7 and 8.8mg/kg for cocoon and juvenile production, respectively, compared to 9.2 and 9.1mg/kg for TNX, respectively. The EC20 values for the total number of cocoon hatchlings were 3.1 and 4.7mg/kg for MNX and TNX, respectively, in soil and 4.5 and 3.1mg/L in the topical test. Both MNX and TNX inhibited cocoon production and hatching, suggesting that they may have a negative affect on soil ecosystems at contaminated sites. 相似文献
47.
Assessment of sediment contamination in Casco Bay, Maine, USA 总被引:1,自引:0,他引:1
The current status of contaminant concentrations in Casco Bay, decadal trends of these contaminants and changes in their geographical distribution are assessed using sediment samples collected approximately 10 years apart. In general, regulated contaminants appeared to be decreasing in concentration. Total PAH and dioxins/furans concentrations did not significantly change over this period. Total organochlorine pesticides, 4,4-DDE, 4,4-DDD, total DDT, PCB, tributyltin and total butyltin decreased in concentration. Trace element concentrations in sediments decreased at the majority of the sampling sites for chromium, nickel, and selenium while arsenic, cadmium, copper, lead, mercury, silver, and zinc remained relatively constant. None of the contaminants measured has increased by more than a factor of 2. Selected sites located in the Inner Bay, where concentrations are higher and new inputs were more likely, showed increased concentrations of contaminants. Most contaminants were not found at concentrations expected to adversely affect sediment biota based on ERL/ERM guidelines. 相似文献
48.
We collected and analyzed 955 individual fish (six species) for sexual differences in PCB bioaccumulations from a southeastern, USA reservoir. Using 2-way ANCOVAs, we found significant differences in fillet PCB concentrations between sexes for channel catfish (Ictalurus punctatus), largemouth bass (Micropterus salmoides) and spotted bass (Micropterus punctulatus). Striped bass (Morone saxatilus), black crappie (Pomoxis nigromaculatus) and freshwater drum (Aplodinotus grunniens) did not display differences between sexes in PCB concentrations. We suspect that sexual differences may be due to biological differences in reproduction, relative motility and lipid deposition. For one species (striped bass), sexual differences in PCB concentrations were inconsistent with a study in the Hudson River suggesting that sexual differences in bioaccumulations can change across ecosystems. Two species which did show sexual differences, largemouth bass and channel catfish, are often chosen as representative species (e.g., "piscivore" and "benthivore") in contaminant monitoring in many USA states indicating human consumption and risk management decisions would be improved if an equal number of male and female fish were included in composite PCBs analysis. This could reduce variability in fish PCBs data from which consumption advisories are based. 相似文献
49.
There is currently uncertainty on the persistence of active pharmaceutical ingredients (APIs) and on their depletion mechanisms in natural surface waters such as rivers, and hence predictions of their fate are often poor. In this study, a beta-adrenergic receptor, propranolol hydrochloride, was selected as a model API to explore the relative significance of direct phototransformation as a potential removal process of hydrophilic APIs in rivers. Phototransformation kinetics of propranolol was measured under simulated solar irradiation in the laboratory, which were then converted to the kinetics applicable in UK and US rivers. The effects of light intensity, light penetration, river size and flow were examined. The extrapolated phototransformation half-lives were applied in the river catchment models of GREAT-ER and PhATE. Results demonstrated that direct phototransformation significantly reduced the predicted environmental concentrations of propranolol in the water phase. Predicted reductions of mean concentrations in the River Aire (UK) were 27% in summer and 3% in winter; and for the US rivers simulated, reductions were 28-68% in summer and 11-41% in winter. The highest reductions were predicted for long rivers with low turbidity and low flow conditions. 相似文献
50.
Life history costs of olfactory status signalling in mice 总被引:4,自引:0,他引:4
L. M. Gosling S. C. Roberts E. A. Thornton M. J. Andrew 《Behavioral ecology and sociobiology》2000,48(4):328-332
Large body size confers a competitive advantage in animal contests but does not always determine the outcome. Here we explore
the trade-off between short-term achievement of high social status and longer-term life history costs in animals which vary
in competitive ability. Using laboratory mice, Mus musculus, as a model system, we show that small competitors can initially maintain dominance over larger males by increasing investment
in olfactory status signalling (scent-marking), but only at the cost of reduced growth rate and body size. As a result they
become more vulnerable to dominance reversals later in life. Our results also provide the first empirical information about
life history costs of olfactory status signals.
Received: 15 December 1999 / Revised: 6 June 2000 / Accepted: 24 June 2000 相似文献