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Hi All, Aug 4, 2008
The mention of pavement leads into another but avoidable negative
effect of most paved surfaces; the almost immediate movement of
rain/snow water to storm drains and and thence to waterways. An excerpt
from my e-mail of June 26, 2001 on this topic is pasted below.
START OF PASTE\\\\\\\\\\\\\\\\\\\\\\\
URBAN WATERSHEDS: Much urban precipitation never has the opportunity
to nourish plants or feed springs. It goes straight from pavement to storm
drains and then to outflow channels. Some farsighted individuals in the
EPA attempted to do something about this and porous pavement was developed
and tested (Thelen, Grover, Hoiberg and Haigh 1972, Conclusions section
from the investigations of porous pavements for urban runoff control).
"Use Porous Pavement" doesn't have the crowd appeal of "Save the
Rainforest" and so far as I know, porous pavement has not been widely
used. According to an abstract of Swedish tests, it withstands frost
better than normal pavement.
///////////END OF PASTE
On a related note, I walked past the pond that is in the Halifax
Public Gardens recently and noticed that it was green and almost opaque
with microscopic algal growth. I didn't notice any agricultural
activities nearby.
Yt, Dave Webster, Kentville
P.L. Chalmers wrote:
> HI there,
>
> This thread about human disturbances to small animal movements
> strikes a chord with me. I often visit the Frog Pond at Fleming Park
> in Jollimore, which has a variety of habitats in a small area and
> hosts an wide range of species for an urban park. This spring the
> gravel shoulders of the Purcell's Cove Road in this area were paved
> and designated bicycle lanes, which I thought at first was a
> progressive move. Earlier this week I was surprised to find that the
> large gravel parking lot adjacent to the pond was also being paved.
> In other years I have watched Painted Turtles scraping out their nests
> in the gravel of that parking lot. I now realize that a significant
> portion of the local nesting habitat of the pond's large Painted
> Turtle population has been paved over. I wonder where they will go now?
>
> Cheers,
>
> Patricia L. Chalmers
> Halifax
>
>
>
> At 05:59 PM 31/07/2008, Dave Webster wrote:
>
>> Hi Lisa & All, July 31, 2008
>> I dare say you are already moving in this direction, but a small
>> animal underpass, suitably located (e.g. where you were escorting
>> toadlets in this instance) would be less labour-intensive and
>> consequently more practicable in the long run.
>>
>> Why Conservation organizations have not lobbied for and made
>> public noises about small animal crossings beats me. Perhaps I have
>> not been paying attention but I have noticed that some have been
>> installed in the UK. Even modest highways with light traffic can be
>> effective barriers to movement of Reptiles and Amphibians, either by
>> preventing access to the roadway or by killing some that do make it.
>>
>> Based on road kills observed while walking, I think snakes must
>> sun on gravel roads where they blend in nicely before and after being
>> flattened. And a 20-cm high ridge of gravel, thrown up by a road
>> grader, can stop a 30-cm snake from crossing. And a highway sand cut,
>> at angle of repose after about 25 years, acts as a solid wall to a
>> toad (in dry weather; wet might be different).
>>
>> Yours truly, Dave Webster, Kentville
>
>
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