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&g --001a113eff8caa64b80527e0d1f9 Content-Type: text/plain; charset=UTF-8 Hi Dave I can't get Bill's article right now but the New England counterpart article in Env Man (1987, vol 11, 659) says.."Calcium appears to be the nutrient most susceptible to depletion with 13% of the total site calcium removed in whole-tree clearcut products" (Abstract but these authors analysed exchangeable and total Ca ). Bill took the same approach I believe. The New England pit samples were to 60cm. So Bill's study finding that whole tree harvest would remove 27% of site Ca shows that northern temperate forests are more susceptible with latitude, something that works against the movement of calcium requiring woodland flora. These plants are often called the rich mesophytic plants or mixed mesophytic or here the Alleghanian flora. Shelly Porter and Tom Herman studied them along the Meander River (Maidenhair Fern there), and we showed that even in these richest of NS deciduous forest sites, the floodplain forest (3 times more Ca in top of A horizon--10 cm- at floodplains versus uplands), there was a strong positive relationship between species richness of a signature guild of spp (those with big seeds which were mostly rare..Lilium, Triosteum, Caulophyllum Allium Sanguisorba but also Impatiens Uvularia Arisaema) and total calcium. This meant that bringing in the Appalachian hardwood plants into our province will be difficult because the plant community richness is linked to calcium but high calcium sites are rare and calcium is the most susceptible not only to forestry but to acidification (John Smol data using Daphnia in freshwater benthos layers as an indicator of the loss of calcium over last 60 years). Nick On Sun, Dec 27, 2015 at 7:11 AM, David & Alison Webster <dwebster@glinx.com> wrote: > Hi Nick & All Dec 27, 2015 > A key question in this discussion is what fraction of soil calcium is > under consideration ? Is this exchangeable Ca and soil was sampled to what > depth ? > > Yt, DW, Kentville > > > > ----- Original Message ----- > > *From:* Nicholas Hill <fernhillns@gmail.com> > *To:* naturens@chebucto.ns.ca > *Sent:* Saturday, December 26, 2015 7:30 PM > *Subject:* RE: [NatureNS] Red Herring & Forestry > > Steve, > Bill Freedman had these data and Garbary and I referred to his paper w > Morash as well as to a paper on a fractional analysis from New England. > .conn..The take home message was that while biomass removal removed 13% of > the soil calcium in new England, a similar harvest removed 27% of soil > calcium in Nova Scotia. > > This story has another Dal connection: Barry Goldsmith, forest ecologist > who worked at Dal before Bill Freedman. Barry (FB Goldsmith, we have lost > touch) figured that on average NS forests had been cut over 3 times. This > figure is about right if we take a harvest once every 80 years rate and we > might increase this estimate (made in 1980) to 3.5 times cut taking into > account we are 36 years past his time and that times between harvests have > diminished. > > So with 27% loss of calcium per harvest and forests being cut over more > that 3 times, we could make a calculation of: > > A. Loss of Ca in NS forests (our cuts do not remove all biomass) > And > B. How much worse shape we are in in comparison w Connecticut > > So what? > > David Garbary and my finding (Botany in 2011) showed that NS has a group > of rare Appalachian herbs that are restricted to our highest calcium > forests; floodplains, even though in Appalachia they grow on upland slopes. > With climate change plant distributions will move north but only if we have > not exhausted our soils. > > We should be able to do something with these data. > > Nick > On Dec 24, 2015 4:52 PM, "Stephen Shaw" <srshaw@dal.ca> wrote: > >> A question regarding Fred & Peter's point about loss of nutrients. >> In a natural deciduous forest of any type that has not been harvested at >> all, for a 100-year old tree (say), what proportion of the total recyclable >> nutrients per tree-area will have come from the accumulated annual leaf >> fall (+ fallen dead branches + feasting caterpillar, squirrel and >> woodpecker turds, etc), and what proportion will be returned only after the >> woody trunk and main branches have finally died, fallen down and decayed at >> age 100? >> If the first is dominant then the argument about loss of nutrients by >> logging and tree removal is not strictly valid, whereas if the second >> dominates, it is. >> >> I'm sure somebody must have looked at this carefully, and for different >> types of forest and different soil types. Are the proportions known? >> Steve >> ________________________________________ >> From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on >> behalf of Fred Schueler [bckcdb@istar.ca] >> Sent: Thursday, December 24, 2015 12:28 PM >> To: naturens@chebucto.ns.ca >> Subject: RE: [NatureNS] Red Herring & Forestry >> >> Quoting John and Nhung <nhungjohn@eastlink.ca>: >> >> > Yeah, I get the impression that the main problem with the Point Tupper >> > monster is its size. A smaller operation might have fit in quite >> nicely. >> > Of course, the NewPage surprise added to the mess, but mess it is, and I >> > hope the government ad the operators can ramp back its biomass >> consumption >> > to a more sensible, sustainable scale. >> >> * I was crafting a more complex reply to this thread, but I'll just >> say that the problem with biomass harvesting from forests is to get >> the nutrients removed in the wood back into the forest so successive >> generation of trees can grow at a decent rate. We tried to deal with >> this in our county forest here but certain foresters reacted so >> negatively to the question of fertilization that the advisory >> committee was illegally terminated as a consequence - but here's our >> discussion of the nutrient question in forests that are having wood >> removed - http://pinicola.ca/limnutr.htm - on sand and limestone we've >> got very low intrinsic levels of nutrients, but the problem exists in >> all woods if they're intensively exploited. >> >> fred. >> ========================================================== >> > >> > Fingers crossed for a mild winter, with minimum demand for firewood! >> All >> > this tells me we still need to take solar heat and other renewable >> sources >> > more seriously. >> > >> > -----Original Me