The influence of coniferous afforestation on lowland farmland bird communities in Ireland: different seasons and landscape contexts

Current governmental policy in Ireland is encouraging afforestation, 80% of which is likely to consist of exotic conifer species, in low-lying agricultural areas. Whereas most studies of bird diversity in forest/farmland mosaic landscapes have focused on high quality woodland remnants in a hostile agricultural matrix, this study has considered the influence of man-made plantations in a less intensively farmed context. Bird communities of three lowland agricultural landscapes (each 2000 ha in area) with intermediate or low levels of coniferous forest cover (33% or 8% approximately) were sampled in winter and summer. Though total abundance and species richness of birds of farmland habitats in the partially forested and open sites did not differ, the presence of trees in the surrounding landscape did influence abundance of some common species such as Blue Tit Parus caeruleus, Robin Erithacus rubecula and Blackbird Turdus merula. In winter, species composition of farmland habitats with and without hedgerow trees differed between forested and open landscapes. Also, the abundance of certain species varied between farmland adjacent to and remote from forest edges, in both seasons. In these landscapes, coniferous plantations did not greatly affect the mainly generalist farmland bird community, either positively or negatively. However, if the proportion of land-use occupied by forestry were to increase, reducing the available hedgerow habitat and forest edge/area ratio, diversity and abundance of declining farmland bird species might be negatively affected.     

Distribution of generalist and specialist predators along urban gradients

The distribution of predators in urban areas is overlooked by urban planners. Due to the homogenizing power of urbanization, towns are expected to favour the settlement of generalist predators. We compared the frequency of specialist and generalist predators along an urban gradient (centre, inner periphery, outer periphery, and scarcely built areas) in towns of different size (small, medium, large). We obtained data on specialist (diurnal and nocturnal raptors, Dendrocopos major) and generalist (Larus michahellis, corvids) predators breeding in each square of the grid of 27 urban atlases. The number of species per square of specialist predators decreased in more urbanised sectors, whereas the number of generalist predators either did not change or increased in the same sectors. However, some specialist (nocturnal raptors except Athene noctua) and generalist (Garrulus glandarius, Pica pica) predators did not follow such a pattern of distribution. Town size may affect the distribution of predators. Some species (D. major, G. glandarius, P. pica) were more frequent in the more urbanised sectors in small towns. Data gathered in few towns on a limited number of predator species may not fully represent the complex response by predators to urban gradients. Urban planners should consider the distribution of predators in towns to limit risks for urban wildlife.     

Mixture design of high performance recycled liquid crystal glasses concrete (HPGC)

This study investigated the best mixture design of high performance recycled liquid crystal glasses concrete (HPGC) using waste liquid crystal glass sand to replace part of the fine aggregate. The design of experiment (DOE) method was adopted to design the specimen variables. Fresh properties were examined, including slump, flowing slump and unit weight and hardened properties were examined, including compressive strength, elastic modulus, impact-echo, ultrasonic pulse velocity and surface resistance. Range analysis and analysis of variance (ANOVA) were conducted to determine the relationships between these properties and W/B, replacement ratios and n values. The results demonstrated that the ultrasonic pulse velocity and surface resistance of HPGC was higher than those of the control group. For the three n values, higher than ultrasonic pulse velocity was found at a replacement ratio of 30%. The replacement ratios, W/B, and relationships between n values were analyzed. F statistics indicated significant impact on the replacement ratio of 4.97 and W/B of 3.87, indicating that the main properties of the HPGC are determined by the replacement ratio and W/B. The range analysis results showed that the interaction between various factors with W/B = 0.28:1 and n = 1.4 has the most significant impact on compressive strength.     

Effects of loading rate on rock fracture: fracture characteristics and energy partitioning

By means of the Scanning Electron Microscope (SEM), an examination was performed of the fracture surfaces (including their vertical sections) of both Fangshan gabbro and Fangshan marble specimens fractured at the loading rates MPa m^1/2 s⁻¹. The results showed that one or more branching cracks near the fracture surfaces of dynamic rock specimens were clear and the cracks increased with increasing loading rates. However, such branching cracks were rarely seen near the static fracture surfaces. In addition, with the aid of the Split Hopkinson Pressure Bar (SHPB) testing system and a high-speed framing camera, the energy partitioning in the dynamic fracture process of a short rod (SR) rock specimen was analysed quantitatively. The total energy W_L absorbed by an SR specimen in the dynamic fracture process mainly consisted of the fracture and damage energy W_FD and the kinetic energy W_K of flying fragments. The energies W_L and W_K could be quantitatively calculated through stress wave measurement and high-speed photography in the SHPB testing system. Thus, the fracture and damage energy W_FD could be obtained. The results showed that: (1) the energy W_K increased with an increase in the impact speed of the striker bar or the loading rate; (2) the energy W_FD for dynamic rock fracture was markedly greater than that for static rock fracture, and the W_FD increased with an increase in the impact speed of the striker bar or the loading rate; and (3) the value W_L/W_B (W_B is the energy input into the loading system) in the case of dynamic fracture is much lower than that in the case of static fracture. In addition, the ratio decreases with an increase in the loading rate or the impact speed of the striker bar. This means that the energy utilisation decreases when the loading rate or the impact speed of the striker bar rises. Finally, some application problems are discussed in the paper.     

Shear fracture (Mode II) of brittle rock

Mode II fracture initiation and propagation plays an important role under certain loading conditions in rock fracture mechanics. Under pure tensile, pure shear, tension- and compression-shear loading, the maximum Mode I stress intensity factor, K_Imax, is always larger than the maximum Mode II stress intensity factor, K_IImax. For brittle materials, Mode I fracture toughness, K_IC, is usually smaller than Mode II fracture toughness, K_IIC. Therefore, K_Imax reaches K_IC before K_IImax reaches K_IIC, which inevitably leads to Mode I fracture. Due to inexistence of Mode II fracture under pure shear, tension- and compression-shear loading, classical mixed mode fracture criteria can only predict Mode I fracture but not Mode II fracture. A new mixed mode fracture criterion has been established for predicting Mode I or Mode II fracture of brittle materials. It is based on the examination of Mode I and Mode II stress intensity factors on the arbitrary plane θ,K_I(θ) and K_II(θ), varying with θ(−180°θ+180°), no matter what kind of loading condition is applied. Mode I fracture occurs when (K_IImax/K_Imax)<1 or 1<(K_IImax/K_Imax)<(K_IIC/K_IC) and K_Imax=K_IC at θ_IC. Mode II fracture occurs when (K_IImax/K_Imax)>(K_IIC/K_IC) and K_IImax=K_IIC at θ_IIC. The validity of the new criterion is demonstrated by experimental results of shear-box testing.Shear-box test of cubic specimen is a potential method for determining Mode II fracture toughness K_IIC of rock since it can create a favorable condition for Mode II fracture, i.e. K_IImax is always 2–3 times larger than K_Imax and reaches K_IIC before K_Imax reaches K_IC. The size effect on K_IIC for single- and double-notched specimens has been studied for different specimen thickness B, dimensionless notch length a/W (or 2a/W) and notch inclination angle α. The test results show that K_IIC decreases as B increases and becomes a constant when B is equal to or larger than W for both the single- and double-notched specimens. When a/W (or 2a/W) increases, K_IIC decreases and approaches a limit. The α has a minor effect on K_IIC when α is within 65–75°. Specimen dimensions for obtaining a reliable and reproducible value of K_IIC under shear-box testing are presented. Numerical results demonstrate that under the shear-box loading condition, tensile stress around the notch tip can be effectively restrained by the compressive loading. At peak load, the maximum normal stress is smaller than the tensile strength of rock, while the maximum shear stress is larger than the shear strength in the presence of compressive stress, which results in shear failure.     

Mercury in feathers of wild birds from the mercury - polluted area along the shore of the Shiranui Sea, Japan

Total mercury content in the feathers of 95 stuffed, wild birds collected all over the shore of the Shiranui Sea (where Minamata disease occurred in many towns and villages in the 1960's) was measured. They were collected over 25 years, from 1955 to 1980. They showed relatively high mercury levels till the late 1970's, although drainage of waste water containing methylmercury from the Chisso Corporation's Minamata Factory was stopped in 1968. In addition, a strong correlation between feeding habits and mercury content was observed; thus the five groups in order of diminishing mercury content were: fish-eating sea birds (mean ± SD = 7.1 ± 3.7 ppm, N = 14), omnivorous water fowl (5.5 ± 5.6 ppm, N = 17), predatory birds (3.6 ± 2.9 ppm, N = 16), omnivorous terrestrial birds (1.5 ± 1.2 ppm, N = 31), and herbivorous water fowl (0.9 ± 0.4 ppm, N = 17). Mercury content of the feathers of omnivorous terrestrial birds in the Shiranui Sea was exceedingly high compared with those in China and Korea. The findings in the present study suggest that stuffed, wild birds may be a good index of past environmental pollution.     

Multiple indices of body condition reveal no negative effect of urbanization in adult house sparrows

As urbanized areas expand and develop throughout the world, the importance of understanding their effects on wildlife increases. Living in cities may be stressful for animals but may also provide benefits at the same time, and the sum of these effects should manifest in the body condition of individuals. Studies addressing this phenomenon tend to evaluate one or few indices of body condition, each of which may be subject to various confounding effects and seasonal changes. In this study we used multiple approaches to assess the effects of urbanization on adult body condition in house sparrows (Passer domesticus), a passerine undergoing population declines in urban habitats. In line with earlier studies, we found that sparrows in more urbanized habitats have reduced body mass. However, birds had similar scaled mass index (body mass corrected for body size) along the urbanization gradient at all times of the year, contradicting the previous result on type-1 regression residuals. In the non-breeding season, urban and rural birds had similar levels of corticosterone, hematocrit, and heterophil:lymphocyte ratio. In the molting season, hematocrit indicated better condition in rural birds whereas H:L ratio showed the opposite; however, these trends were not consistent between age groups. Two condition-dependent plumage traits, male bib size and wing bar size, showed no systematic variation along the gradient of urbanization. These results suggest that the environmental conditions experienced by adult house sparrows are not more stressful in more urbanized habitats, and they also highlight the importance of considering multiple indices of body condition.     

Habitat associations and survey effort for shrubland birds in an urban pine barrens preserve

Inland pine barrens offer the rarest type of shrubland habitat in the northeastern United States and may contribute disproportionately to the regional diversity and conservation of shrubland birds. Testing local habitat specialization and estimating survey effort is needed to inform management of pine barrens for this rapidly declining avian group. We evaluated shrubland bird habitat associations in a heavily urbanized pine barrens of the northeastern United States, and used occupancy-detection sampling and analysis to estimate the number of sample points and surveys for point-based monitoring of shrubland birds in pine barrens. Although forest area was significantly greater than shrubland area, 8 of 11 reliably modeled species showed evidence of association for shrubland, and are thus potentially useful as indicators of pine barrens shrubland quality and management to avert succession. From the analysis of survey effort, we suggest two design options for point-based monitoring of shrubland birds in pine barrens: (1) include enough points to cover at least ～3% of the study area and survey each point ≥5 times preferably during 05:00–08:00 hr, or (2) reduce the point sample, to no less than about 2% of study area, and increase the survey replication to ≥10 surveys. Three surveys, as suggested by shrubland bird experts for anthropogenic early-successional habitats (e.g., utility corridors) and by others as a general rule, may require too many sample points to feasibly monitor shrubland birds in pine barrens.     

Thaw-induced deformation properties of frozen soils

Materials derived from laboratory study of thaw-induced settlement of soils residing in the central portion of the Bovanenkovsk gas and oil field (GP-2) are presented. The dependence of the thaw-induced settlement of the soils on various parameters (W, ρ, i _i , i _tot , etc.) was investigated. Experimental thaw-induced settlements are compared with those calculated from different relationships.     

Arsenic association and stability in long-term disposed arsenic residues

Long-term stability of arsenic residues is investigated by determining arsenic phases remaining in gold mining residues after two decades of impoundment. The residues, generated by arsenic coprecipitation with iron and lime, were disposed of in-lined sites for 9-16 years (pit C) and 16-23 years (pits A and B). Arsenic is present in the residues as As(V) species, predominantly in the form of amorphous iron arsenate (55-75% As_total, pits A and B; 55-70% As_total, pit C) and sorbed onto amorphous iron-oxyhydroxides (20-33% As_total, pits A and B; 22-37% As_total, pit C). The presence of minor Ca-arsenate phases (undefined composition) and Al-arsenate coprecipitates is also indicated. The passive enrichment of iron in pits A and B, and the relative low concentration of calcium, sulfur and arsenic if compared to those of pit C, suggest that a soluble Ca-arsenate phase (e.g. CaHAsO₄.H₂O), a fraction of gypsum and As(III) were dissolved along 16-23 years of residue disposal. The presence of As(V) only and excess iron demonstrates the importance of the oxidation state and high Fe/As ratio on long-term stability of arsenic residues.     

Wind conditions and ventilation in high-rise long street models

We regarded high-rise cities as obstacles and channels to wind. We first studied wind conditions and ventilations in idealized high-rise long street models experimentally and numerically with a constant street width (W = 30 mm), variable street heights (H = 2 W, 2.5W, 3W, 4W), variable street lengths (L = 47.4W, 79W, 333W, 667W) and a parallel approaching wind. The flow rates penetrating into windward entries are a little larger than the reference flow rate in the far upstream free flow through the same area with windward entries in all models. The stream-wise velocity decreases along the street as some air leaves upwardly across street roofs. Near the leeward entry, there is a downward flow which brings some air into the street and results in an accelerating process. In the neighborhood scale long streets (L = 47.4W and 79W), wind in taller streets is stronger and the ventilation is better than a lower one. For the city scale long streets (L = 333W and 667W), a constant flow region exists where the vertical velocity is zero and the stream-wise velocity remains constant. In such regions, turbulent fluctuations across the street roof are more important to air exchange than vertical mean flows. In a taller street, the process to establish the constant flow conditions is longer and the normalized balanced horizontal flow rate is smaller than those in a lower street. In the city scale long streets, the turbulence exchange rate can be 5–10 times greater than the mean flow rate.     

Modification of -equation in the SSRC Guide for buckling of monosymmetric I-beams under transverse loads

Finite element buckling analyses of monosymmetric I-beams subjected to transverse loading applied at different heights with respect to the mid-height of the cross-section were conducted. Transverse loads consisting of a mid-span point load and a uniformly distributed load were considered in the investigation. Four types of end restraint also were considered. The method suggested in SSRC Guide was compared with the finite element method (FEM) results. In order for C-equation in the SSRC Guide to be applicable for monosymmetric I-beams, it must be modified to contain three variables; A_m, B_m, and D_m. The first two variables A_m and B_m are modified variables A and B in the SSRC Guide whereas the third variable, D_m, developed herein, is the new modification factor for monosymmetric I-beams. The applicability of this new design rule is limited to monosymmetric I-beams in which the degree of monosymmetry, ρ, is within the range from 0.1 to 0.9.     

Shotgun metagenomics of dust microbiome from flight deck and cabin in civil aviation aircraft

Microbial exposure is related to the health of passengers on commercial aircraft, but no studies characterized the microbial composition at the species level and identified their ecological determinants. We collected vacuum dust from floor and seat surfaces in flight decks and cabins of 18 aircraft, and amplification-free shotgun metagenomics was conducted to characterize the microbial composition. In total, 7437 microbial taxa were identified. The relative abundance for bacteria, eukaryote, viruses, and archaea was 96.9%, 1.8%, 0.3%, and 0.03%, respectively. The top bacterial species mainly derived from outdoor air and human skin included Sphingomonas, Corynebacterium, Micrococcus luteus, Variovorax paradoxus, Paracoccus dentrificans, and Propionibacterium acnes. The abundance of NIAID-defined pathogens was low, accounted for only 0.23% of total microbes. The microbial species and functional composition were structured by the indoor surface type (R² = 0.38, Adonis), followed by the manufacturer of the aircraft (R² = 0.12) and flight duration (R² = 0.07). Indoor surfaces affected species derived from different habitats; the abundance of dry skin and desiccated species was higher on textile surfaces, whereas the abundance of moist and oily skin species was higher on leather surfaces. The growth rates for most microbes were stopped and almost stopped.     

Tunnel roof deflection in blocky rock masses as a function of joint spacing and friction – A parametric study using discontinuous deformation analysis (DDA)

The stability of underground openings excavated in a blocky rock mass was studied using the discontinuous deformation analysis (DDA) method. The focus of the research was a kinematical analysis of the rock deformation as a function of joint spacing and friction. Two different opening geometries were studied: (1) span B = h_t; (2) B = 1.5h_t; where the opening height was h_t = 10 m for both configurations. Fifty individual simulations were performed for different values of joint spacing and friction angle. It was found that the extent of loosening above the excavation was predominantly controlled by the spacing of the joints, and only secondarily by the shear strength. The height of the loosening zone h_r was found to be dependent upon the ratio between joint spacing and excavation span S_j/B: (1) h_r < 0.56B for S_j/B  2/10; (2) stable arching within the rock mass for S_j/B  3/10. The results of this study provide explicit correlation between geometrical features of the rock mass, routinely collected during site investigation and excavation, and the expected extent of the loosening zone at the roof, which determines the required support.     

Birds of Siberian-pine (Pinus sibirica) forests of the south-east part of Western Siberia (Tomsk Region)

Abstract

The article examines the fauna and bird population of Siberian-pine forests in Tomsk Region (the south-east part of Western Siberia) in the summer period. The article is based on data collected by the authors over many years in 12 areas of Siberian-pine forests in various forest subzones. The taxonomical structure of avifauna, the landscape and ecological structure, and species distribution are examined. A comparison has been made of species diversity and population density for birds of sub-taiga Siberian-pine forests in the southern and middle taiga. The authors have identified the leading species of birds in terms of population density in various forest subzones. A tendency towards latitudinal changes in species diversity and population density in Siberian-pine forests has been discovered. The authors have identified the species of birds whose diet includes the nuts of Siberian pines. Data on the bird species of Siberian-pine forests listed in the Red Data Book of Tomsk Region have been included.     

Breakage and re-growth of flocs: effect of additional doses of coagulant species

Several polyaluminum chloride (PACl) coagulants were prepared, with different OH/Al ratios (B values), and characterized by Ferron assay. These were used in studies of floc formation, breakage and re-growth with kaolin suspensions under controlled shear conditions, using a continuous optical monitoring method. Particular attention was paid to the effect of small additional coagulant dosages, added during the floc breakage period, on the re-growth of broken flocs. The results showed that the re-growth ability was greatly dependent on the nature of the PACl species added as second coagulant. The re-growth ability of broken flocs was greatest when the second coagulant was PACl₀ (i.e. AlCl₃, with B = 0) and least with PACl₂₅ (B = 2.5). In the latter case there was no effect on floc re-growth, irrespective of the initial coagulant used. PACls with intermediate B values gave some improvement in floc re-growth, but less than that with PACl₀. Additional dosage of PACl₀ gave re-grown flocs about the same size or even larger than those before breakage. The re-growth of broken flocs is significantly correlated with the species Al_a (monomeric) and Al_b (polymeric), as determined by Ferron assay. The amorphous hydroxide precipitate formed from PACl₀, (mainly Al_a) can greatly improve the adhesion between broken flocs and give complete re-growth. However, for PACl₂₅, mostly composed of Al_b, the nature of the precipitate is different and there is no effect on floc re-growth.     

A simple but exact method for vibration analysis of composite laminated plates with all edges simply supported and under lateral and in-plane loading

A simple but exact method of calculating the natural frequencies of vibration for some structural members with all edges simply supported and under lateral and in-plane loading, is presented herein. This method uses the deflection influence surfaces which can be obtained by any method for vibration analysis and consists of determining the deflected mode shape of the member due to the inertia force under resonance condition. Beginning with initially guessed mode shape, exact mode shape is obtained by the process similar to iteration. In this paper, equations are given for the case of special orthotropic laminates. However, the same equations can be used for any laminate as long as B₁₆, B₂₆, D₁₆, and D₂₆ are negligible as the number of plies increases and some laminates having such properties are presented.     

Bird and small mammal abundance at four types of waste-management facilities in northeast Ohio

Location of waste-management facilities in urban and suburban areas is increasingly controversial for a variety of reasons. Because traditional putrescible-waste landfills often attract large numbers of gulls (Larus spp.) and other birds, they can present a significant risk to air-traffic safety when located near airports. The Federal Aviation Administration (FAA) provides recommendations for the location of putrescible-waste landfills and other waste-management facilities near airports because of the potential for bird—aircraft collisions.To extend the life of traditional putrescible-waste landfills, many communities are turning to non-traditional waste-management facilities such as yard-waste compost facilities, construction and demolition landfills, and trash-transfer stations. These types of facilities may present potential bird-strike risks, and may attract nuisance birds such as starlings (Sturnus vulgaris) and rock doves (Columba livia), and nuisance mammals such as Norway rats (Rattus norvegicus). Objective data are needed on bird and mammal use of these facilities for wildlife biologists to advise regulatory agencies and local governments on the siting and management of these facilities.From May 1993 to April 1994, we compared bird species and numbers at five non-traditional waste-management facilities of three types in northeastern Ohio with species and numbers at a vacant lot (control site) and at a major putrescible-waste landfill. We also surveyed small mammal species and numbers at two compost facilities, a vacant lot, and a small wooded lot. Bird abundance at the five facilities was no different than, or less than, at the vacant lot. About 350 times more birds were seen per observation at the putrescible-waste landfill than at the other five waste-management facilities. Bird use of these non-traditional waste-management facilities appears to be influenced much more by the type of habitat or land-use surrounding the facility than by the waste itself. Fewer small mammals were caught at the compost facilities than at the vacant lot and wooded area. Thus, these non-traditional waste-management facilities do not appear to attract birds or small mammals at higher than background levels and would not pose a significant nuisance problem to the community or be a hazard to aircraft if located near airports.     

Toxicite des eaux de ruissellement de la fonte de neige en milieu urbain

There is a current paucity of information on the characteristics of water originating from melting snow in urbanized areas. In fact no data exist on the potential chronic toxicity of waters originating from melting snow combined with sewage waters of industrial and domestic activities. Bioassays were conducted on the green alga Selenastrum capricornutum to evaluate the composite effect of all pollutants occurring in waters originated from melting snow in urbanized areas and also to determine the long-term bioavailability of selected toxicants in these waters.The publication resumes a sampling study of two outfalls (Curotte-Papineau and Meilleur-Atlantique) from collector systems on the island of Montréal, Québec, Canada (see Fig. 1). Both sewer systems are of the combined surface runoff-wastewater type, are self contained and drain watersheds of 11.7 and 22.2 km² area respectively (see Table 1). The sampling program carried out in spring (March–May) 1978, was oriented towards the analysis of flow-quality relationships during two dry and three snowmelt periods. The flow from the intrusion of snowmelt into the sewage networks were due not only to high air temperature and solar radiation conditions but also to a heavy rainfall (9.67 mm; maximum intensity of 4.6 mm h⁻¹. The principal water quality parameters studied were BOD₅, COD, Cl⁻, N_in, P_i, Pb, Cr, Zn, Cn⁻ and SS (see Table 2).In addition a bioassay based on the fertility potential [the Selenastrum capricornutum Printz algal assay bottle test; U.S.E.P.A. (1978)] on filtered samples (1.2 μm GF/C) of waste water was used to detect any toxological qualities of the outfalls during both dry and snowmelt periods. An analysis of the relationship between chemical quality and the toxological properties of the samples from both sewage networks showed that water collected during a period of snowmelt without rain had a greater potential chronic toxicity and greater mean ratios of B_EDTA/B than combined water collected during a dry climatic period (see Table 3). This toxicity is due mainly to inorganic compounds. However, the increase in water discharge rate during periods of snowmelt accompanied by rain results in an apparent dilution of the aquatic toxicants. The potential chronic toxicity of water during the latter periods is consequently reduced compared with combined waters during dry periods.Knowledge of relationships between water flow and the chronic toxicity characteristics of waste water from urban snowmelt is necessary in the planning of any future combined water treatment system.