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Climate change and ecosystems JOANNA WIBIG. Changes of timing of phenophases Changes in ranges of species and biomes Biodiversity Ecosystems productivity. Phenology has been in the focus of scientists since the studies of Karl Linn é and Robert Markham.
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Climate change and ecosystems JOANNA WIBIG
Changes of timing of phenophases Changes in ranges of species and biomes Biodiversity Ecosystems productivity
Phenology has been in the focus of scientists since the studies of Karl Linné and Robert Markham Phenology: the study of the timing of recurring biological phases, the causes of their timing with regard to biotic and abiotic forces, and the interrelation among phases of the same or different species.
Phenology can be divided into: • Phytophenology • Agrophenology • Zoophenology
Early spring phases (pollination of hazel and coltsfoot) occur now 10-20 days earlier than 50 years ago Spring phases (birch leaf unfolding, lilac and apple trees in full bloom) now occurs 5-15 days earlier than 50 years ago
The rate of phenophases changes (in days per year) birch leaf unfolding
Phytophenological records in the Baltic Sea Basin have the tendency to earlier appearance of sprong and early spring phases. These trends seems to be stronger in the baltic region than in the whole Europe.
Ar the same time there is tendency to later appearance of fall phases. The lenght of vegetation period defined as a time of appearance and loss of leaves by different tree species has been lenghten significantly. An average trend of spring phases is -2 days per decade The fall phases are later +1.6 days per decade. The vegetation period becames longer 3.6 days per decade.
Birds: • changes in ranges (breedingplaces, winteringplaces, migrationroutes), • changes in migration timing, • chasnges in breeding timing, • changes in live length, • changes in productivity.
Birds try to winter as close to the breeding place as possible, so their migration routes became shorter, and the birds use less energy for migration. Greylag goose (gęś gęgawa) from Sweden wintered in Spain, now most of them winter in the Netherlands. In the transition period those who choose the Netherlands use less energy so their chance to survive is higher.
Cranes (żurawie) wandered to Spain, now nore and more of them winter in Meklemburgia, or even in Poland in Western Pomerania.
ROBIN (RUDZIK) LEPWING (CZAJKA) Many Polish birds, which wintered in Western Europe (France Spain) now try to winter in western Poland . At the moment it concerns single specimen or small groups, but the tendency is evident.
It does not mean that warming favours nigrating birds. Inceasing of Sahel region has tremendous and negative effect for enormous amounts of birds wintering on the south of Sahara, because enlarging desert takes away suitable wintering areas. The amount of storchs in Poland in 30 per cent is related to amount of rain in Sahel. In dry years a lot of birds falls on the Sahel, where they stay in their return way to Europe. Similary, it is suspected that climateic changes will have an adverse impact on shore birds (ptaki siewkowe), which breed in Arctic (Syberia) and winter in Africa and have only 1 or 2 breaks in their journey (a few thousands of km!) . Climate changes cause that capturing of food and energy will be more difficult and takes more time.
Changes in timing of migration Timing of migration (measured as a day of arrival to Europeanbreedingplaces and dates of departure) change with climatechanges. The majority of speciescome to breedingplaces in the Central Europe earlierduringlast 20-25 years. The rate of thesechangesisstronglydifferentiatedamongspecies.
The greatest changes concern birds wintering in Europe, the smallest those wintering in equatorial and southern Africa. (the changes are smaller in case of birds migrating on larger distances). The degree of change of arrival date is different for those coming as first than the last examples of the same species.
Stork (bocian) 10 days earlier Nightingale (słowik rdzawy) 7 days earlier Lepwing (czajka) 20 days earlier Barn swallow (jaskółka dymówka) A week earlier Arrivals Skylark (skowronek) 11 days earlier Cuckoo (kukułka) 7 days earlier House martin (jaskółka oknówka ) 12 days earlier
Changes in breeding terms Breeding terms for many species are well correlated with temperature in thee time preceding breeding, the warmer spring the earlieer breeding. Climate warming causes accelerating of laying eggs for many species, but this acceleration is different for different species.
Earlier nesting– more eggs– better viability of nestlings – higher reproduction level Climate changes cause a diminishing of differences in quality of birds in specific species. Those examplares, who laid their eggs later and have smaller hatches (because they were not able to collect food and produce eggs earlier) are now in better position. The differences in the reproduction level among birds of the same species diminish.
Changes in productivity The amount of food for nestlings change in the breeding season. The amount of insects especially caterpillars has its peak. The date of laying eggs was evolutionary adjusted to the peak of food for nestlings.
Temperature in early spring is a crucialkfactordetermining the moment of peak of catterpillars. Whenitiswarmerthispeakcomesearlier. Birds try to forecast this moment. They evolutionary have got mechyanisms of forecasting on the basis of spring temperature. Thatiswhyterms of layingeggsarecorrelated with spring temperature. Theytry to bringforthyopungexactly in time of peak of caterpillars.
Climate changes disturb this proces , because the thermometers of birds and their food are not identical Because of warming a peak of caterpillars comes earlier. Birds are not able to manage with evolutionary adjustment to new situation. They accelarate a laing eggs time but not enough.
Decision rules of insectivorous birds (green line) and insects (red line) according to timing of laying eggs. Together with temperature rise the insects accelerate their peak in caterpillars amount faster than the birds accelaerate their time of laying eggs. That is why the young birds appear after the peak of caterpillars.
Among non-climatological factors are: • atmospheric CO2 concentration • natural disturbances (floods, wildfires) • land use • habitat fragmentation • absence of suitable habitats due to human activities Distributional shifts are the result of two different mechanisms operating at local scale: • expansion into new areas due to climate amelioration • local extinction, which reduces the distribution
Thermal factors Disadvantages of warm winters • lack of hardening • lack of winter cooling • better conditions for pests • lack of snow cover Advantages of warm winters • milder winters • longer vegetation period
Humidity factors • higher evapotranspiration • more precipitation in winter • lack of water from snow melting at the beginning of vegetation period • lack of snow cover Light factor
Beech buk In the Baltic region there is a few tree species which ranges moved to the north and/or higher altitudes. Lime lipa In Scandinavia ranges of beech, lime, oak and spruce have changed paralelly to the cumulative sum of temperature of winter season in the last 8000 year. The contemporary rate of climate change is faster from analogous changes in the past. Oak dąb Spruce świerk
Currently the naturally-regenerating holly, a good climate indicator, has expanded east and northward of the previously reported natural limit, coinciding with the advance of 0°C January isoline. Birch brzoza Pine sosna Holly ostrokrzew Rowan jarzębina In the Swedish part of Scandes mountain range upslope shifts of 100-150 m of birch, pine, rowan, spruce and willow is reported, coinciding with 0.8°C increase in mean temperature since the late 19th century Willow wierzba
Animals generaly copy the changes in structure of the environment; that is why changes in ranges of animal species are parallel to changes in ranges of their food Changes in ranges of some species can result in extinction of them, because of habitat losses, fragmentation, delays of transformation and so on…
Climate-related invasions The clearest evidence for a climatic trigger for large-scale changes in ecosystem structure occurs where a suite of species with different histories of introduction spread en-masse during periods of climatic amelioration Wasplike spider, previously restricted to southeastern Europe, in recent decade has expanded its geographical range to the northern parts of Europe, colonizing Germany, Poland, Denmark and Sweden Tygrzyk paskowany Among factors causing rapid geographical expansion of wasplike spider are: • increase of numbers of sunny and dry days in summer • floods of large rivers in Europe • establishment of large open habitats due to deforestration and drainage
Weather-regime changes are among important factors controlling invasion of parts of Europe (including the Baltic region) by the leaf miner moth – an important pest of horse-chestnut trees. leaf miner moth horse- chestnut tree devastated by leaf miner moth
Caterpillar nymphs winter on leaves of horse-chestnut lyind on the ground. They can survive enen -25 °C. First grown up individuals appear at the end of April. The eggs are laying singly along main nervation of the leaves. Larvas grow inside leaf blade. Metamorphosis of grown up caterpillars take place inside. It can be even 700 caterpillars. The leaves with caterpillars fall. Trees captured by leaf miner moth have second flowers in the autumn, but there is no chance for fruits. Additionally second flowering weaken trees. They are sick in witer and easy to frozen. In Poland leaf miner moth has usually 3-4 generations during one year.
Changes in biome boundaries Altitudinal shifts of vegetation are well documented for many parts of the Earth. Higher temperatures and longer growing seasons, associated with climate change, have released new areas for colonization by certain plant species For the Baltic region one robust conclusion can be drawn: endemic mountain plant species are threatened by the upward migration of more competitive sub-alpine shrubs and tree species
Higher winter temperatures and frost episodes Due to winter hardening, changes in mean and minimum temperatures of the coldest month and number of frost days do not increase the risk for frost damage. Damage occurs during frost episodes when the plants are not adequately hardened, it can happen at any time of the year, but is common after a longer period of warmer temperatures in spring when dehardening has been initiated. Higher winter temperatures can induce change in plant phenology, as thermal requirements for dehardening and budburst will be fullfiled earlier. Species that are strongly regulated by light will be less affected than those strongly regulated by temperature.
Heat spells and reduced summer precipitation Water shortage lowers the transpiration, photosynthesis and uptake of mineral nutrients. The response is non-linear affected by duration and frequency of drought stress. The severity of heat spells and drought will increase the risk for forest fires Both an increased frequency of heat spells and reduced summer precipitation increase the risk for drought stress. Soil water potential, ambient light intensity, temperature and wind influence the severity.
Changes in autumn and winter precipitation Due to climate change, a reduction in snow cover is expected. In regions with a thin snow cover and low winter temperatures, the soil will be deeply frozen. Soil frost increases the risk of winter desiccation, occurring when the trees are exposed to higher temperatures in spring increasing transpiration, but the frozen water can not be taken up. In areas with an increased precipitation during autumn and winter, the risk of waterlogging will increase. This can cause anaerobic root conditions and kill parts of the root system. The plant will become more susceptible to drought stress and attacks by patogens.
There is evidence of recent productivity increases for ecosystems within or near the Baltic catchment region. Overall growth trends for European forest ecosystems have been positive during the last 50 years. • increased temperatures • the fertilisation effect of anthropogenic nitrogen deposition • management avtivities • increased CO2 level In some cases, recent climate change may be associated with growth reductions. Dittmar et al. (2003) showed a declining growth trend for European beech (Fagus sylvatica) at higher altitudes during the last 50 years. Correlations with climate parameters suggest that an increased preponderance of wet, cloudy summers coupled with late frosts reduced vigour and growth for this species. The negative growth trend was most pronounced for the period 1975-1995, even though increasing CO2 levels, N deposition and an extended growing season would all be expected to have positive impacts on production.
Senstivity of growth in Scots pine (left) and Norway spruce (right) in different parts of the Baltic Sea basin compiled from the findings of SilviStrat project (Lindner et al. 2005). Rovaniemi - the northern boreal forest Kuopio- southern boreal forests Chorin and Grillenburg temperate forests in northern Germany.
