scholarly journals Costs and Benefits of Green Tramway Tracks

2020 ◽  
Vol 51 (4) ◽  
pp. 99-106
Author(s):  
E. Jakubcová ◽  
E. Horváthová

AbstractIn recent decades, green tramway tracks have still more often been installed in many cities as an alternative to standard rails placed on concrete sleepers or grooved rails since the vegetated tracks are beneficial to urban dwellers. In this article, we summarize and compare the benefits of grass and low-maintenance tramway tracks and link them with their investment and maintenance costs in two Czech cities. We conclude that grass surfaces offer a slightly higher rainwater retention capacity, while the rest of the benefits are similar for grass and low-maintenance surfaces. The investment costs are also similar, however, the maintenance costs are 30× higher for grass surfaces than for the low-maintenance ones.

2009 ◽  
Vol 87 (5) ◽  
pp. 415-421 ◽  
Author(s):  
R. A. Ronconi ◽  
J. M. Hipfner

We tested predictions concerning the significance of egg neglect for the burrow-nesting seabird Cassin’s auklet (Ptychoramphus aleuticus (Pallas, 1811)) at a colony where endemic Keen’s mice (Peromyscus keeni Merriam, 1897) depredate unattended eggs. A video-camera probe was used to monitor neglect and predation in 32 burrows, and mass loss of incubating adults was measured in 12 separate burrows. Incubating birds lost 8.1% of their body mass over obligate 24 h incubation shifts, suggesting that incubation is costly. In response, most pairs (79%) neglected their egg at least once. As predicted, rates of neglect decreased as incubation progressed, and the costs of neglect increased. Rates of neglect increased during periods of strong winds, which create poor foraging conditions at sea. Contrary to predictions, rates of neglect did not increase when burrows were colder and self-maintenance costs were higher. Neglect was risky in that rates of egg loss by predation increased with frequency of neglect. Increased neglect early in incubation and during periods of poor foraging conditions, despite high rates of predation on neglected eggs, is consistent with the existence of a fitness trade-off between costs and benefits of neglect.


2019 ◽  
Vol 42 ◽  
Author(s):  
Amanda R. Ridley ◽  
Melanie O. Mirville

Abstract There is a large body of research on conflict in nonhuman animal groups that measures the costs and benefits of intergroup conflict, and we suggest that much of this evidence is missing from De Dreu and Gross's interesting article. It is a shame this work has been missed, because it provides evidence for interesting ideas put forward in the article.


1998 ◽  
Author(s):  
Pinka Chatterji ◽  
◽  
Lisa Werthamer ◽  
Marsha Lillie-Blanton ◽  
Christine Caffray

Author(s):  
Samuel Taxy ◽  
Akiva M. Liberman ◽  
John K. Roman ◽  
P. Mitchell Downey

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