Martin, please reread what I wrote. I never said that EVERY large greenhouse uses CO2 I said NEARLY. The American Heritage dictionary defines the word NEARLYas an adjective meaning " Almost but not quite". So when I stated "As a matter of fact nearly every large greenhouse on the planet uses CO2 supplimentation." This was clearly an oversimplification and I should have stated, nearly every lagre greenhouse in a climate which requires the house to be closed (primary vetilation) for a majority of the year uses CO2 supplimentation. For the purpose of this conversation it would be wise to define what a "large" greenhouse is. I would define a large greenhouse as having no less that 600,000 sq.ft. (a little more than 13 acres) of growing space. As I am not a statician I would love to know what the rest of you think of that number. To me this seems modest since the average total area under glass and plastic across 36 countries, for any one country is just over 9,400 acres thats 411,173,125 sqft!
I would like it if you could clarify yourself a little more when you say; "We have some models to calculate CO2 injection in the greenhouses for different crops but CAM plants or orchids come up with almost nothing." And "Unfortunately I do not have a report that CO2 fertilization will help or not growing orchids". You appear to be contridicting yourself with these two statements. Matt -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Wednesday, November 22, 2006 5:00 AM To: [email protected] Subject: Orchids Digest, Vol 8, Issue 393 Message: 7 Date: Tue, 21 Nov 2006 14:44:47 -0500 From: Martin Boekholt <[EMAIL PROTECTED]> Subject: Re: [OGD] CO2 gas... To: "the OrchidGuide Digest (OGD)" <[email protected]> Message-ID: <[EMAIL PROTECTED]> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Some facts on fertilization with CO2 in Holland. 1. CO2 is a "waste" product from burning natural gas for creating warmth and electricity on-site so with technical application can be used as an addiction element for crop growing in greenhouses. or a "waste" product sold to soft drink companies and growers by for example yara. Something new in Holland is suppling some 170.000 ton from petrochemical industry by pipelines to dutch growers. OCAP http://www.ocap.nl/Factsheet_UK.pdf This to comply with Kyoto standards. Suppling CO2 in dutch greenhouses has been common for many years first with the application of manure and later with more technical research. And NO not every large greenhouse on THE PLANET uses CO2 fertilization only a small percentage. Supply CO2 is done with absorption ratios C02/m2/hour this ratio depends on crop/light (PAR), water availability and ?C so giving an CO2 boost to 1500 ppm, will not work normally. We have some models to calculate CO2 injection in the greenhouses for different crops but CAM plants or orchids come up with almost nothing. And of course output can be calculated to see if it is economic feasible And times changes things maybe in 1986 Beer found > a situation > can occur under northern European conditions of long nights and low solar > radiation. Today that situation doesn't occur any more in Holland we jut put on the light in the greenhouses. Up to 15.000 lux or 922 j/cm2 in tomatos! With some 100 hectare of mostly phalaenopsis in Holland and growing to an estimated turnover for 2010 of 450 million euro a lot of money is being spend in Holland to get a better crops faster. Unfortunately I do not have a report that CO2 fertilization will help or not growing orchids but because a lot of orchids growers already need to buy WK (warmth/light generators) they already looked into the use of the "waste" product CO2. Hope this information is useful. ------------------------------ _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com End of Orchids Digest, Vol 8, Issue 393 *************************************** -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.430 / Virus Database: 268.14.12/544 - Release Date: 11/21/2006 4:59 PM -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.430 / Virus Database: 268.14.14/547 - Release Date: 11/22/2006 5:41 PM _______________________________________________ the OrchidGuide Digest (OGD) [email protected] http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
