Effects Of Environmental Characteristics Research Articles

Environmental drivers of macrophyte species richness in artificial and natural aquatic water bodies – comparative approach from two central European regions

Species richness of macrophytes of artificial and natural water bodies covering rivers, streams, canals and habitats with standing water was studied in two Central European biogeographical regions, Pannonian and Carpathian, represented by two model areas (the Borská nížina Lowland and the Turčianska Kotlina Basin). We found that: (i) the total number of macrophytes was higher in artificial water bodies compared to natural aquatic habitats in both regions and differences were statistically significant (P<0.05); and (ii) species richness of macrophytes is relatively low in both regions; slightly higher mean number was found in the Pannonian region (3.53) compared with the Carpathian region (3.06). Effects of environmental characteristics on species richness studied by generalized linear model (GLM) showed that explained variances of GLM were similar in both regions. The main drivers of the diversity pattern were those connected with the hydrology of water bodies, such as substrate characteristics and turbidity, less frequent were chemical characteristics, such as water conductivity and N-contents, whereas landscape characteristics manifested the smallest impact.

Design approaches for promoting beneficial indoor environments in healthcare facilities: a review

As a result of growing evidence regarding the effects of environmental characteristics on the health and wellbeing of people in healthcare facilities (HCFs), more emphasis is being placed on, and more attention being paid to, the consequences of design choices in HCFs. Therefore, we have critically reviewed the implications of key indoor physical design parameters, in relation to their potential impact on human health and wellbeing. In addition, we discussed these findings within the context of the relevant guidelines and standards for the design of HCFs. A total of 810 abstracts that met the inclusion criteria were identified through a PubMed search, and these covered journal articles, guidelines, books, reports and monographs in the studied area. Out of these, 230 full publications were selected for this review. According to the literature, the most beneficial design elements were: single-bed patient rooms, safe and easily cleaned surface materials, sound-absorbing ceiling tiles, adequate and sufficient ventilation, thermal comfort, natural daylight, control over temperature and lighting, views, exposure and access to nature, and appropriate equipment, tools and furniture. The effects of some design elements, such as lighting (e.g. artificial lighting levels) and layout (e.g. decentralized versus centralized nurses’ stations), on staff and patients vary, and ‘the best design practice’ for each HCF should always be formulated in co-operation with different user groups and a multi-professional design team. The relevant guidelines and standards should also be considered in future design, construction and renovations, in order to produce more favourable physical indoor environments in HCFs.

Sampling Methods for Assessing Syrphid Biodiversity (Diptera: Syrphidae) in Tropical Forests

When assessing the species richness of a taxonomic group in a specific area, the choice of sampling method is critical. In this study, the effectiveness of three methods for sampling syrphids (Diptera: Syrphidae) in tropical forests is compared: Malaise trapping, collecting adults with an entomological net, and collecting and rearing immatures. Surveys were made from 2008 to 2011 in six tropical forest sites in Costa Rica. The results revealed significant differences in the composition and richness of syrphid faunas obtained by each method. Collecting immatures was the most successful method based on numbers of species and individuals, whereas Malaise trapping was the least effective. This pattern of sampling effectiveness was independent of syrphid trophic or functional group and annual season. An advantage of collecting immatures over collecting adults is the quality and quantity of associated biological data obtained by the former method. However, complementarity between results of collecting adults and collecting immatures, showed that a combined sampling regime obtained the most complete inventory. Differences between these results and similar studies in more open Mediterranean habitats, suggest that for effective inventory, it is important to consider the effects of environmental characteristics on the catchability of syrphids as much as the costs and benefits of different sampling techniques.

Spatial segregation among age classes in cave salamanders: habitat selection or social interactions?

AbstractWithin species, individuals with different sexes, morphs and age classes often show spatial segregation. Both habitat selection and social processes have been proposed to explain intraspecific spatial segregation, but their relative importance is difficult to assess. We investigated spatial segregation between age classes in the cave salamanderHydromantes(Speleomantes)strinatii, and used a hypothetico‐deductive approach to evaluate whether social or ecological processes explain segregation pattern. We recorded the location and age class of salamanders along multiple caves; we measured multiple microhabitat features of different sectors of caves that may determine salamander distribution. We assessed age‐class segregation, and used generalized mixed models and an information‐theoretic framework, to test if segregation is explained by social processes or by differences in habitat selection. We found significant age‐class segregation, juveniles living in more external cave sectors than adults. Multiple environmental features varied along caves. Juveniles and adults showed contrasting habitat selection patterns: juveniles were associated with sectors having high invertebrate abundance, while adults were associated with scarce invertebrates and low temperature. When the effect of environmental features was taken into account, the relationship between juveniles and adults was non negative. This suggests that different habitat preferences, related to distinct risk‐taking strategies of age classes, can explain the spatial segregation. Juveniles require more food and select more external sectors, even if they may be risky. Conversely, adults may trade off food availability in favour of safe areas with stable micro‐climate.

Effects of environmental features on flocking behavior

Social animals or insects in nature often exhibit a form of emergent collective behavior known as flocking. Animal flocks are strongly affected by the spatial heterogeneity representing static environmental factors, such as landscape. To investigate how this heterogeneity affects flocking behavior, I constructed a two-dimensional, lattice-based environment, in which the spatial heterogeneity was generated using a neutral landscape model. A value ranging from 0.0 to 1.0 was assigned to each lattice site. High values represent favorable environmental conditions, and thus, individuals tend to be attracted to the area with the highest values. The value H controlled the degree of heterogeneity and the value h represented the amplitude of the heterogeneity. To characterize the effect of the spatial heterogeneity, I introduced the order parameter, ϕ, defined as the absolute value of the average unit velocity. When all individuals move in the same direction, the value of ϕ is 1, while the value of ϕ becomes 0 in the case where all individuals move randomly. In this simulation, the flock size, N, has the values of 20, 40, 60, 80 and 100. I investigated the average value of ϕ and ϕs, for 1500<t<2000. The simulation results showed that the value of ϕs increased with an increase in H, regardless of N, until becoming saturated. When the value of h was higher, the value of ϕs became lower.

Consistency of toddler engagement across two settings

a b s t r a c t This study documented the consistency of child engagement across two settings, toddler child care class- rooms and mother-child dyadic play. One hundred twelve children, aged 14-36 months (M = 25.17, SD = 6.06), randomly selected from 30 toddler child care classrooms from the district of Porto, Portugal, participated. Levels of engagement were coded, and sophisticated engagement, but not nonengage- ment, was consistent across settings. Consistency in children's sophisticated engagement was primarily accounted for by chronological age. Children spent more time in sophisticated behaviors and less time nonengaged during mother-child dyadic play than in center-based child care. For sophisticated engage- ment, effects of child predictors were stronger than effects of environmental features; whereas for nonengagement, effects of environmental features were stronger than effects of child predictors. Find- ings suggest children's sophisticated engagement may be generalizable across settings, as a function of age, whereas their nonengagement is most likely context dependent.

How organizational slack affects new venture performance in China: a contingent perspective

PurposeThe purpose of this paper is to investigate the relationships between organizational slack, environmental characteristics, and new venture performance in China. The paper focuses on how different types of organizational slack, such as absorbed slack and unabsorbed slack, impact Chinese new venture performance. And it also examines the moderating effects of environmental characteristics, such as munificence and dynamism, on the slack‐performance linkage in Chinese transitional context.Design/methodology/approachA literature review on organizational slack and institutional environment characteristics provides the model and hypothesis. Using a sample of 91 Chinese new ventures, the authors conduct the examination on the theoretical model and hypotheses.FindingsThe results show that the relationship between absorbed slack and new venture performance is negative and unabsorbed slack has an inverse U‐shaped effect on new venture performance. Furthermore, the institutional environments, such as munificence and dynamism in transitional economies have different moderating effects on the relationship between organizational slack and new venture performance.Research limitations/implicationsThis study focuses on the new ventures of China, which is context specific. It is necessary to replicate this research in other transitional economies because of some specific differences between China and other transitional economies.Practical implicationsThe results of the study suggest that new ventures should strengthen the management of resources and decrease absorbed slack in order to reduce the managerial cost, and then raise the level of resource utilization. In addition, how the new ventures make better utilization of organizational slack to deal with institutional environment uncertainty would be a core task in future business operations.Originality/valueThe paper is original in its investigation of the effect of organizational slack on new venture performance in contingent transitional environments. The paper explains the relationship between different types of organizational slack and new venture performance from a contingent perspective, thus extending the extant research.

Influences of Built Environment on Walking and Cycling by Latent Segments of Aging Population

Walking and bicycling are relatively easy ways for the growing group of older adults to be physically active. The built environment may facilitate or restrict participation in walking and bicycling trips. A study was done to describe aspects of participation in walking and bicycling activities and to explore their role for various segments of the aging population. Specifically, the effect of environmental characteristics, various types of land use, and degree of urbanization on participation in walking and bicycling, for both leisure and transportation, was examined. Detailed individual travel data were correlated with objectively defined environmental attributes. The results show that people make more walking trips in more highly urbanized areas, whereas they use their bikes more often in less-urbanized areas. A significant effect was found for the impact of total surface of recreation areas on both types of physical activity. Specifically, highly urbanized neighborhoods with a low percentage of recreation and green areas are related to physical inactivity. The study suggests that compact, high-density neighborhoods may not be a good urban design concept if health is considered.

A few good women - on top management teams

AbstractOur study extends the upper echelon framework to gender diversity in top management teams (TMTs), a topic that has received littleattention in management. We study the direct impact of representation of women on TMTs on organizational performance. We also study themoderating effects of environmental characteristics on the TMT women–performance linkage. In a sample of 679 firms from the 1998Fortune 1000 list, our results show a positive relationship between the proportion of women on TMTs and organizational performance. Themoderating effects of environmental characteristics, namely, munificence, dynamism, and complexity, are not supported. These results revealthat the role played by top women managers transcends the demands of the environment. Our study has implications for the careerdevelopment of women. In addition, our results have the potential to generalize to managers from other nationalities.D 2004 Elsevier Inc. All rights reserved. Keywords: Women; Top management teams; Performance; Fortune 1000 firms

Effect of environmental characteristics onPythiumandMesocriconemaspp. in golf course greens in Alabama

The role the environment has on populations of Pythium and Mesocriconema spp. was investigated at 5 golf course locations in east central Alabama. Every 4 to 5 weeks soil samples were collected from 3 golf greens on each of the 5 golf courses. Environmental data, including air and soil temperature, pH and relative humidity, were also collected. Dilution plating and a combined sieving and sugar flotation procedure were conducted to determine the populations of Pythium and Mesocriconema spp. for each month. Isolates of Pythium from 4 months were also identified. Pythium spp. populations increased as soil temperature and ambient air temperature prior to sampling decreased (P < 0.05). Pythium spp. populations were highest in the winter and lowest in the spring. At some locations, populations of Mesocriconema spp. increased as soil acidity and populations of Pythium spp. decreased (P < 0.05) and as ambient air temperature prior to sampling increased (P < 0.05). Eight species of Pythium were isolated from 4 months, with Pythium rostratum being the most commonly isolated. Results suggest that Pythium and Mesocriconema spp. prefer different soil environments.

The potential effect of environmental conditions on the growth of irrigated cool season pastures in the Dohne Sourveld

Four temperate grasses (Festuca arundinaceae, Festuca X Lolium hybrid, Lolium boucheanum and Lolium multiflorum) were grown under irrigation at the Dohne Agricultural Centre. The object was to determine the monthly growth and nutritional value of the grasses. The effects of environmental features on the growth rate of the pastures were investigated. Polynomial regression of the environmental features against growth rate was used to create transformed values, which were then subjected to stepwise linear regression. In some cases it was possible to describe the growth rate, expressed as the increase in yield (g ha−1) per minute of day length, in terms of temperatures, minimum humidity and increasing day-length. The growth rate of F. arundinaceaae reached a maximum at a mean average temperature of 18°C, and that of L. boucheanum at 16°C. Festuca arundinaceae's growth rate is depressed less by higher temperatures than that of L. boucheanum. Seasonal growth patterns (t DM ha−1 month−1) and fibre and N content ...

Microscale and finescale variations of small plankton in coastal and pelagic environments

Small-interval water sampling in oceanic subsurface layers in a variety of macroenvironments for microplankton and for characteristics of their environment revealed concentration variations that often exceed errors of sampling and measurement. I report incidence and degree of microscale and finescale organism patchiness and their dependency on the local environment and on certain characteristics of the organisms themselves. Scale analysis indicates that patchiness occurs below as well as above the 20 cm intervals sampled. Incidence and degree of patchiness were about the same in separate eastern boundary regions, off California and Peru. Effects of environmental characteristics on organism patchiness are clearly defined in this data set, which suggests influences by physical processes on local microplankton patches on the scale of a few centimeters (microscale) to a few meters (finescale). In the aggregate, finescale and microscale patchiness of microplankton populations was greater at lower wind speeds, during daylight than at night, and over continental slopes. Patchiness was greater in the more stable layers of the seasonal pycnocline, and under more oligotrophic conditions (lower concentrations of nutrients, particulates, and chlorophylls). Patchiness of organisms also was greater where nutrients and particulates were more patchy, but was unrelated to chlorophyll patchiness. Intrinsic properties of the organisms less clearly affected microplankton patchiness. Population patchiness was greater for autotrophs and heterotrophs than for atrophs, and was slightly greater for larval fish competitors and predators than for their prey, and for more motile organisms. Reproductive capacity is indicated to dominate among intrinsic patch-forming attributes. Smallscale patchiness of small plankton is a recurrent feature of the environment of small predators and may affect their growth and survival. Its incidence and degree appear to be specifiable over large domains from parameters of the mixing environment, e.g. wind stress and vertical stability. This would contribute to management of exploited stocks of marine organisms whose recruitment depends on food supply at early stages of their life-history.

Strategic Planning: Determining the Impact of Environmental Characteristics and Uncertainty

This paper continues a line of research into the effect of environmental characteristics and uncertainty on strategic planning. Results suggest that measures of uncertainty and the environment need to be analyzed independently, and that uncertainty is a strong moderator of environmental characteristics and industry groupings but does not consistently affect strategic planning activities.

The Effects of Environmental Characteristics on the Structure of Hospital Clusters

The population ecology view that variation in sets or clusters of organizations should be isomorphic with variation in cluster environment was used here to explain structural variation among hospital clusters. The structural characteristics studied were range of services offered within the cluster, average size of hospitals in the cluster, and cluster differentiation. In the causal model that was developed and evaluated, variation in the patient environment and variation in the supplier environment were compared. Four lagged panels of data on a national sample of fifteen hospital clusters demonstrated the relative superiority of supplier variables over patient variables. Supplier group preferences were more powerful than patient needs in determining the range of services offered by the cluster. Furthermore, increasing the range of services in the cluster had a positive, significant effect on average hospital size, whereas size apparently exerted no effect on range of cluster facilities. Cluster differentiation seems to be causally affected by range of services, average hospital size, and by the periodic closing of hospitals over time.