Ashwani:
You are doing a great service to an urgent need--cross-fertilization of the
disciplines (or at least they can be) of planning and ecology, as well as
drawing attention to a little-appreciated subject in the context of
ecosystems. And, you are working in urban environments, where ecosystems
are largely broken, dysfunctional, or at best, degraded. Beyond that, you
are actually doing something, not just talking about it. We need more
planners like you.
Most important, we need more ecologists working with planners, even
developers, to achieve the goals like the one you've set out for yourself.
I appreciate the bibliography, too, and hope that others will help you both
build it up in both numbers and quality--by annotating entries, for example,
and providing reviews.
As for me, I'd be happy to help you with any specific issues or the
examination of broad principles. However, your question "What would be the
ecosystem effects of converting substantial portions of urban impervious
surfaces to permeable and porous materials?," while a good question, has so
many facets that any "answer" is bound to be limited. Perhaps there is a
book here that you could write.
As I have emphasized before, I think it is far more important to work from
principles and details than from methods and techniques. That said, I have
worked on the overall issue of watershed restoration and management for some
time, and have worked out some practical applications that can be adapted to
a wide variety of urban contexts, but they are beyond (but are certainly
inclusive of) the issue of permeable pavements, important as it is.
Understanding the fundamental principles of hydrology ("micro-" hydrology
must be included) sufficiently well to apply them to a variety of contexts
is not difficult, but it is vital. The same for soil biology, but the
chemistry can be quite challenging. This is where teamwork is essential.
If you could get the right hydrologist(s), wildland soil specialist(s), soil
chemist(s), soil microbiologists, ecologists, and other specialists
together, you should be able to ramp up your schedule quite a bit.
A first step in answering your question would be to assess the infiltration,
percolation, and other subsurface water-movement potentials. For example,
if a site has had its biologically-active soil graded away in the act of
paving, it may have limited potential for transmitting water unless it is
altered--not always a cost-effective thing to do. Soil organisms can be
introduced, or allowed to colonize, depending upon the circumstances; these
are essential for soil health and can be the cheapest, easiest, most
effective ways to reduce runoff, improve infiltration and percolation, and
restore soil health that can be used--even when it IS technically and
financially feasible to resort to "hard" engineering measures. Perhaps the
most potential lies in new construction or reconstruction, but retrofitting
need not be ignored. As you are aware, sometimes the lack of political will
and fear are the biggest obstacles.
You have a long, hard row to hoe (if you will pardon the irony of the
expression), but it is a worthy, even heroic task.
Keep us posted!
Best,
WT
----- Original Message -----
From: "Ashwani Vasishth" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Saturday, June 21, 2008 7:09 PM
Subject: [ECOLOG-L] Ecological Impacts of impervious surfaces on soil health
I've started a bibliography at
http://www.csun.edu/~vasishth/Soil_Ecology_Biblio.htm, and would
appreciate any suggestions.
Specifically, I want to know what do we do to soils when we pave them
over? What would be the ecosystem effects of converting substantial
portions of urban impervious surfaces to permeable and porous materials?
(I have enough on the ground water recharge and storm water runoff aspects
of such a move, its the soil health component that I want to get at.)
Incidentally, I'd also be interested in any pointers to understanding the
idea of soil diversity, and the argument that we are destroying it at a
planetary level.
Thanks,
-
Ashwani
Vasishth [EMAIL PROTECTED] (818) 677-6137
http://www.csun.edu/~vasishth/
