Crop pollination in Norwegian Fjords and climate change Stein J. Hegland 1. Research Manager at the Norwegian Red deer Centre 2. Guest researcher at the.

Crop pollination in Norwegian Fjords and climate change

Stein J. Hegland1. Research Manager at the Norwegian Red deer Centre

2. Guest researcher at the University College of Sogn and Fjordane

My role

• Involved as national partner– contribute to design and methodology etc– administrate field work(ers) and collect data– writing process

• Research interest: plant-animal interaction– pollination ecology– herbivory (mainly large herbivores)

• Authored conceptual review on plant-pollinator mismatches in relation to climate warming: Hegland, S.J., Nielsen, A., Lázaro, A., Bjerknes, A.L. & Totland, Ø. (2009) How does climate warming affect plant-pollinator interactions? Ecology Letters, 12, 184-195.

The Norwegian Fjords

• positive effects on regional climate

• makes fruit production possible «close to arctic»– ca 0-100 m.a.s.l

• climate gradients are strong within the fjords

An example from ecological

research that uses the climate

gradient: SeedClim

http://www.uib.no/en/rg/EECRG/55395/seedclim

• Most important Norwegian crops (in tons):1. apple (11440)2. strawberry (9122)3. raspberry (2262)4. plums (1102)5. sweet cherry (537)6. blackcurrant (592)7. pears (360)

Crop pollination

• Pollinators are decisive or increase production in 35% (#87) of world crops

• In 2005: value of insect pollination put to 153 million Euros annually (ca 10% of the total value of the worlds agriculture)

• I Norway we know little, but we reckon that most of the important crops need pollination and in practise honey bees are often used as additive to natural pollinators

Source: Christmann & Aw-Hassan (2012). Agriculture Ecosystems & Environment

Fruit ImportanceBumblebees Solitary bees Honeybee Syrphids Other flies

Apple x x x x LargeBlackcurrant x x x ModeratePears x x x ModeratePlums x x x x LargeRaspberry x x x x LargeStrawberry x x x x ModerateSweet cherry x x x x LargeSource: Klein et al. 2007. Proceedings of the Royal Society: Biological series

Pollination of fruit and berriesPollinators

• Norway: apple, rasberry and sweet cherries as likely study candidates due to economics and dependence on pollinators

Crop production and climate change issues in Norway

• Today: Climatic sensibility to fruit production and pollination– cold and wet weather in pollination season

• Climate change now and future: Increased and/or heavy precipitation:– less pollinators active + decrease in bees?– harm flowers?– increased parasite problems, especially fungi?

• tunnel production is partly an arrangement to meet these challenges

• Increased temperature: probably positive– better pollination and growth– more bee species in the long run?– drought issues for some crops?

The Norwegian Fjords: a climate change laboratorium?

• Gradients in temperature, precipitation and sun exposure (local climate) within the fruit growing area

• For example the Sognefjord fruit districtFruit growing area

Part of gradient July mean temperature (°C)

Precipitation (mm)

Exposure

Lærdal Inner 14-17 ca 500 flat (valley)Luster Inner 14-17? ca 900 south-southeastLeikanger Middle 14-17 994 southVangsnes (Vik) Outer 14-17 1138 northBalestrand Outer 14-17? 1700 southeast

Earlier flowering across time

Climate research challenges• Previous table highlight the importance of assessing the «real»

climate gradient– not necessarily linearly related to altitude or continentality!– thus: establish the climate gradient may be important work

• How link changes in pollination success to climate changes?– changes along climatic gradient is not enough!– thus: observational gradients (within + among countries) + experiments on

important mechanisms?• bagging?• pollen supplementation?• warming treatment?• precipitation teatment?• etc!?

• An important task for this workshop?

A holistic view: crop pollination as part of the landscape is the main strenght of this project

How is the surrounding landscape benefitting crop production?

• Many examples on how landscape configuration, distance to and amount of (semi-)natural elements etc – affect pollinator diversity and abundance and

therefore crop pollination and production• How about competition vs facilitation for pollinators

among native flowering resources and crops?– Scale and distance matters, but little investigated– Applied knowledge: remove or enhance natural

flower resources and on which scale?

Crop pollination and changing landscapes

• Semi-natural elements rich on nesting and flower resources are getting scarcer throughout Europe– a bit slower in Norway, but cultivated landscapes

are turning into forest or intensified

Practise I

• Honey bees are used, but in varying degree depending on beekeeper abundance

• Wild pollinators are relatively abundant– andplantations are relatively small– tunnels (raspberry) is a potential

challenge for some pollinator species?

Practise II

• Apple producers often remove dandelion and other (flowering) vegetation to avoid competiton for bees (and resources)– Free, J.B. (1968) Dandelion as a competitor

to fruit trees for bee visits. Journal of Applied Ecology, 5, 169-177.

• Also common to remove flowering resources within plantings of other fruits and berries

Scale-dependent effects of floral neighbourhood

Hegland, S.J. (2014) Floral neighbourhood effects on pollination success in red clover are scale-dependent. Functional Ecology, in press

Scale-dependent effects of floral neighbourhood

• Facilitation of visitation to red clover at small scale changing to competition at intermediate scale and facilitation again at larger scale

• Methodologically challenge: measure flower abundance at different spatial scales

• Also: one need precise hypothesis.– In this study only facilitation/

competition by density of similar couloured flowers

Hegland, S.J. (2014) Floral neighbourhood effects on pollination success in red clover are scale-dependent. Functional Ecology, in press

Summing up

• Norwegian Fjords: a potentially interesting natural climate laboratorium– in itself and in relation to other areas with distinct climate

gradients– requires high quality study-design and thought-through

experiments along climate gradient(s)• Both climate and landscapes are changing in these areas

– both potentially positive and negative effects of climate– knowledge on climate change effects are scarce– knowledge on effects of management of surroundings and

landscape change are scarce