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Global warming and seed orchards in Sweden. Dag Lindgren Department of Forest Genetics and Plant Physiology Swedish University of Agricultural Sciences Umeå Seed orchard meeting IUFRO WP 02-09-01 Korea, Sept 11, 2009. http://www-genfys.slu.se/staff/dagl/korea09/. The big picture….
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Global warming and seed orchards in Sweden Dag Lindgren Department of Forest Genetics and Plant Physiology Swedish University of Agricultural Sciences Umeå Seed orchard meeting IUFRO WP 02-09-01 Korea, Sept 11, 2009 http://www-genfys.slu.se/staff/dagl/korea09/
The big picture… • Life is important for climate! • Human has an accelerating impact on environment and climate. • I read a book this summer, Ward: ”The Medea hypothesis”. It teaches that Life is destabilising climate and self-destructive. • ”Back to Nature” will not save Civilisation with its too large and growing population. • Humans must manipulate the climate in a wise way. • Seed orchards are an important brick in that puzzle.
How has Sweden prepared for an uncertain future? • Structuring of long term breeding and testing • Increased use of seed orchards with robust and flexible seeds
Map of Sweden with heat sum instead of longitude.The breeding population is structured in many subpopulations with different targets. This contributes to gene conservation and diversity and preparedness for changing environments Seed orchards are recruited from several populations BP Target of a breeding population
To prepare for an uncertain future, efforts are spread towards sea level and timber limit more than optimal for a constant environment! Timber limit Sea Level BP Target of a breeding population
The recruitment population is tested over a range of environments around the target environment! Selection will create more plastic and stable genotypes than Evolution can do!Evolution knows only now and here!!!!Tree breeders can do better than that!
Seed orchards is one response to an uncertain future • Seed orchards are predictable and reproducible. • Orchard clones are selected from a wide range of stands and tested on several different sites and recruits from different set of materials. This gives seeds suitable for variable conditions. • A sufficient number of clones (17-25?) guarantees genetic diversity and flexibility.
Predicted environmental changes make seed orchards more motivated • Warmer climate reduces problems to produce seeds for the harshest sites • Renewable resources instead of fossil! • More energy from forest! • More sequestring of carbon dioxid • More oxygen supporting life • Against deforestation • Symbol for sustainability and trust in future • Seed orchards can be immediate modified to new requirments (by roguing, selective harvest). • Seed orchard seeds can be used on other places than initially planned if environment change. • The argument that autotoctoneous provenance reflects local adaption looses much of its weight with global warming and environmental change.
Strategy to changing conditions is not mainly a question about objective prognosis, it is more about : • philosophy • politics • polical correctness • trustworthyness • safety • uncertainty of prognosis
A general strategy to meet uncertainty is diversification. The future has become more uncertain, so more diversification is motivated.
Response to more uncertainty!Breeding materials are tested over a slightly wider range of environments!
Species use may change • Environmental change, diversification and species conservation motivates seed orchards of many species. • Room for low input seed orchards of species with low current demand!
Global warming – come to stay • Global warming has been uncertain – now we have to deal with it as a matter of fact –if we believe it or not – It will become warmer the next 100 years! • How will and should this affect reforestation, forest tree breeding and in particular establishment of seed orchards? • Immediate action seems needed, but how?
Suggestion for within species decisions for forestry • Act now as if temperature will rise two degrees between 1991-2090. • Accept consequences for tempsum, spring phenology, etc. (Direct temp related). • Do not consider other predicted future changes for choice of genetic material within species (no change for e.g. precipitation, wind, continentality, parasites).
Reason for two degrees/century • Few scenarios predict less than two degrees rise in a century neither for Sweden, nor the world. • Big enough to have effects – in particular if the change will be larger, the negative effects will be smaller than if no change today. • Small enough to be safe – if temp remains constant, the harm will be limited. A global warming over all Sweden is not 100% sure! • A bit conservative, but psychologically better to start with actions, which later will be regarded as the right direction, than to act so it will be judged too radical in a decade. • Good enough to use immediatly while waiting for better guidelines! • Simple and transparent!
All do not agree on global warming • The models do not predict everything correct and are thus not perfect. • There are many quantitative large factors affecting e.g. carbon dioxid. • There are complex interactions.
The environmental change is very uncertain!Weather forecasts of temperature one and two days ahead in my hometown. Temp at Umeå, actual and predicted one and two days ahead Question: Why trust in forecasted temperature rise in a century knowing that predictions two days ahead have a standard error of 2 degrees? Accurate temperature prognosis is impossible!!
The variation between adjacent years is often two degrees and decade averages vary more than a degree
Reasons to wait with reacting on other predicted effects of clima change • The temperature is the most evident effect and even the size of that change is highly uncertain. • If other effects are considered, less emphasise will be made on temperature. • The debate would be complex; speculative; depending on specialised experts; ”black box dependent”; not transparent; mistakes easier done or hidden behind propaganda of intressents or idea monglers. • Other effects are often better considered by species change than within species change.
Why start 1990? • The period 1961-1990 is a meteorological standard period, it is most logic and simple to start from 1990! • Our experience on transfers is mainly based on before 1990 events. Provenance trials have been established and measured mainly 1955-1990. • Most Swedish plus trees have been selected before1990. • Till 1990 the ”warming” was insignificant, slow and well within natural fluctuations. • Suggested model: A continuous change from 1990 to 2040, one degree in half a century, two in a century.
Swedish temp to 2001 “Dag’s extrapolation” seemed an overestimate 2001. Red arrow = ”Dag’s extrapolation” for Swedish global warming
But, “Dag’s extrapolation” looks an underestimate 2007 Red arrow = ”Dag’s extrapolation” for ”Swedish” global warming
Two time perspectives • Forest plantations (recommendations). The regeneration is most sensitive the first years, the established stand is more plastic. It is suggested to assume half a degree temperature rise (thus conditions 2018) in planting recommendations. • Seed orchard establishment. It takes decades till seed production starts. It is suggested to assume one degree temperature rise (conditions 2046) for seed orchards planned today.
How to mimic temperature change? • Pretend to change the elevation first, thus move forest genetic material downward rather than southward. • Logic. Physics says that air cools when lifted! And observations say that it is colder at high altitudes! • Temperature in Swedish vegetation period rises around 0.6 degree when elevation is reduced 100 m! • Thus, reduce elevation from 1990 to the actual year • Thus 3.5 meter/annually • Or change heat sum correspondingly, but this is less transparent. • Equivalent to keeping the heatsum constant at a geographic location! • Effects of temperature change in Sweden can be evaluated from elevational differences in existing trials!
Response to warming:Move the map of Sweden!To keep the heat sum and latitude, the altitude of the breeding population targets increases “Map” of Sweden “Map” of Sweden
If the average temp changes a degree in Sweden... • Phenology changes • The average temperature rises around 5 days faster in the spring. • The average temperature falls around 5 days later in autumn.
A proper respons to warming is to change species. • Room for ”optional” low input seed orchards of ”emerging” species. • The seed need should be covered in a scenario with no warming ”business as useful”, but in that scenario the extra seeds could be somewhat less intensive.
The seed need in ”seed orchard zones” will change compared to the plans when seed orchard were established. That affects the target area for new seed orchards and make revisions of seed orchard supply area more radical...
In Sweden sites with a difference of 200 meter elevation or two latitudes, the annual temperature change slightly less than a degree.
I have calculated how optimal use of some seed orchard crops would be expected to change by a warmer climate • I used a program ”Planters guide” by Skogforsk available at the web for predicting ”production” of a forest regeration material as a function of the latitude and elevation of the planting site. • Four seed orchards were compared. Elevation was kept constant and latitude varied. The value where the seed orchard was most superior to the best transferred natural population was set to 100 percent and the production of the seed orchards on other latitudes but the same elevation was related to that value. • The program is based on ”current” temperature (1990). I used 200 m elevation. When I used lower elevations corresponding to the expected higher temperature sum 2018 and 2046.
Scots pine seed orchards, predicted “production” in percent of the highest performance compared to the best provenance at different plantation latitudes
The effects of temperature in this analysis seem surprisingly small, but this is probably specific for Scots pine in northern Sweden, where climate dependent survival is critical.
Area of seed orchard use • The recommendations of using seeds from existing seed orchards are suggested to be adjusted for half a degree warmer climate immediatly. • This seems usually to have rather small effect, in the magnitude avoiding 1-2 percent production loss. • The loss if no climate change occur is small.
Suggestion for recruitment of clones in Sweden for a warmer climate • It seems safer to recruit clones tested at, and with origin from, a lower elevation than from more southern latitudes. With elevation only heat sum changes. With latitude also the ”light climate” changes. The southern may be adapted to another light climate, with the lower it is only the heat.
End • Thanks for attention