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Question: Explain how the pollination and seed dispersal methods of angiosperms would differ in the boreal rainforest compared to tundra ecosystems?

Can someone (maybe who has background experience in Biology 11) help me answer this question on plant reproduction? I need to explain the specific examples to back up the answer. Maybe I just need comparison ideas between the pollination and seed dispersal in the boreal rainforest biome, and ideas between the pollination and seed dispersal in the grassland biome. Thank you in advance!

Hi,

I think you are on the right track thinking about pollination because that is the key to reproduction in higher plants.

The boreal forests like the taiga lie south of the tundra but they are still in the colder north regions so there are fewer plant species overall compared the temperate areas. The trees are mostly conifers which are gymnosperms but there are some angiosperms--alders and birches. Birches and alders are wind pollinated so do not require insects. Boreal herbs and shrubs that have flowers would be insect pollinated and you could compare them to insect-pollinated plants in the tundra.

The tundra is colder than the boreal areas and the ground there is almost permanently frozen. While there are plants there, the diversity is less than in the boreal forest. Likewise the insect populations will be more limited in the tundra.

The growing season will be shorter in the tundra so flowering plants have to grow, flower, get pollinated and set seeds more quickly than in a boreal forest. This limits the type of plants that can thrive.

Temperature is not the only factor, however. Some boreal areas and most tundra regions can be very dry. This also limits plant diversity. I think the effects of global warming are often seen more dramatically in the northern biomes. Plants may flower earlier than before but if their insect pollinators are not around then they may not get fertilized.

I don't know if this answered your question. Ask again if you still need help.

Sybee

This answers my Boreal Forest part of the question. Thank you. Although in the question... I did mean to say Grassland, not Tundra. Opps Could you give me some ideas on what pollination and seed dispersal are like in that biome?

Also what might be some advantages and disadvantages to being a plant in the Boreal Forest area, and likewise to a Grassland biome?

And just for clarification... what is the "Taiga"?

Thanks again

Hi,

Actually I thought tundra was a good choice for comparison. Maybe you should do all three--tundra to the north, grasslands to the south and boreal in the middle.

Before humans started messing with the environment, grasslands stayed grassy because of fire. Most tree seedlings that sprouted in the prairie were killed by lightning-started fires. That's why the prairies were almost all grasses. Also, the average rainfall tends to be lower than the temperate forest regions which favors grasses with their deep, extensive root systems. http://www.thewildclassroom.com/biomes/grasslands.html

The temperate type of grasslands, which I am assuming are the ones you mean, have pretty wide temperature fluctuations--hot in summer and very cold in winter--and this affects the flowering time, insect maturation and seed dispersal. The boreal areas are also very cold in winter, but they are cooler overall and never get as warm in summer.

The western prairies in the U.S. are a good example of a temperate grassland but others include the pampas of Argentina, the veldts of Africa and the steppes of Russia.

Grasses are wind-pollinated so no insects are needed for them, but there are a lot of prairie wildflowers--milkweeds, asters, blazing stars, lupines, coneflowers, phlox and spiderwort. https://gustavus.edu/arboretum/prairielist.php
Wildflowers are pollinated mostly by bees, wasps and butterflies, but also by moths, flies and beetles. http://pollinator.org/pollinator_prairie.htm

In order to act as a pollinator the insect has to be available at flowering time and this timing can be affected by temperature, rainfall, and the presence of insect predators and diseases. https://en.wikipedia.org/wiki/Pollinator
Grasslands like the prairies have an abundance of insects--more than boreal forests and way more than tundra, so if a particular insect species is not present in sufficient numbers to do the pollination then some other species can stand in for it. http://prairieecologist.com/category/prairie-insects/ https://www.agriculture.purdue.edu/agco ... jAXmyuYRts

I hope this gives you enough information to get started. If you go to the websites you can find much more complete discussions of the ecosystems. Decide on the major features like rainfall, high and low temps, average temp, snowfall, and plant and insect species, then make your comparisons centered on these characteristics for each ecosystem ( I still think you should do all three).

If you need more help, that's what we're here for.

Good luck!

Sybee.

Thank you so much! This helps a ton!

Do you have any informative sites on the boreal forest biome that I could take a look at? Maybe even some tundra ones?

Thanks again!

You're welcome!

There's a ton of interesting info on the boreal regions. Oh, by the way--'taiga' is Russian for the kind of forest that English-speaking people call boreal. You can google 'taiga' if you want to read about the Russian boreal forest. It's a big one! There's also a lot of tundra in Siberia. I like hiking or skiing in boreal woods, but tundra is way too cold!

Here are some good sites about the boreal biome:

http://www.thewildclassroom.com/biomes/taiga.html
http://www.blueplanetbiomes.org/taiga.htm
https://en.wikipedia.org/wiki/Taiga
http://www.treehugger.com/natural-scien ... orest.html

And these will tell you about tundra:

http://www.blueplanetbiomes.org/tundra.htm
http://earthobservatory.nasa.gov/Experi ... tundra.php
http://environment.nationalgeographic.c ... a-profile/
https://en.wikipedia.org/wiki/Tundra

This should give you enough info, but if you have some specific questions I can try to answer them.

Sybee