Ecosystem in a Bottle: Week 11

Week Eleven

November 18, 2013

 

Water: The water in our ecosystem is still clear. Even though we poked a hole in our ecosystem last week, the water level does not seem to have gone down any. We still have condensation in the top and bottom of the bottle.

Elodea: The elodea is still floating in the water and looks very healthy. In fact, it is really the only part of this ecosystem that seems to have survived in the environment.

Snails: The snails are both sitting on the gravel at the bottom. They are not stuck to the side of the bottle, which makes us think they may be deceased.

Daphnia: The daphnia are still not visible. The exoskeletons are not even apparent anymore. We believe they are long gone.

Seeds/Leaves: All of our leaves are completely dead. Our plant stalks have shriveled and are turning yellow/brown. The hole we poked in the bottle does not seem to have improved the health of our ecosystem.

Soil: There are still some roots that are visible, but we do not think there are any new roots. It seems our ecosystem has run its course.


Final note: Our ecosystem experiment was quite interesting. We can definitely see how these closed ecosystems could be beneficial in our classrooms. In a class of younger students, we would consider using one class ecosystem for observation rather than individual ecosystems; however, older students would likely benefit from making and observing their own/group ecosystems. We believe that if we had added more soil to the system and/or added fewer seeds, our plants would have fared much better because there would be a sufficient amount of nutrients to keep the bean plants healthy. The bottom of our ecosystem looks healthy, leading us to believe that the top half of the system was malnourished once the soil was depleted of nutrients. Next time around, we would add more soil, observe for a longer period of time post poking a hole in the ecosystem/poke the hole as soon as the plants started to take a turn for the worst, and added more daphnia. If we were working with a class of older students, they could further investigate their own questions pertaining to the completion of the ecosystem project (i.e., How does the amount of soil affect the growth of the plants, why does the elodea seem to be thriving, why did the daphnia disappear so quickly, what could be added to the ecosystem instead of the dapnia, etc.)

Ecosystem in a Bottle: Week 10

Week Ten
November 11, 2013

WATER: the water is still clear. There is still condensation present in the top and the bottom of the system. We drew a new line to mark the water level (since we poked a hole in our system and we want to see if it gets lower). Our water is currently 9.8 cm from the bottom of our system

ELODEA: The elodea is very large and seems to be the only thing in our ecosystem that is really thriving. In the fourth picture, the new line we marked (labeled 'hole') will help us see how much the water goes down.

SNAILS: both snails are in the gravel. we are not sure if they are still alive.

DAPHNIA: We believe the daphnia are long gone as we have not seen them since the first couple of weeks. The exoskeletons of the daphnia are no longer present, even when we swirl the water in the bottle around. This is interesting as usually we could at least see the REMNANTS.  

SEEDS/LEAVES: All of our leaves are highly see-through. They are stuck to the side of the bottle and they are very brown. The stalks themselves are still standing, but they are breaking and wilting. The top limbs of the stalk are browning, and very spindly. It is clear that our ecosystem is not very healthy anymore.

SOIL: THE ROOTS OF THE BEAN PLANTS ARE STILL VISIBLE IN THE SOIL. THERE ARE still ROOTS THAT ARE POKING OUT OF THE TOP OF THE SOIL. No real change is visible. 

UPDATE: We are opening our closed system by heating up a large nail to poke a hole into the top of our system. We are curious to see if this improves the health of our plants, as well as what other changes might occur.

Ecosystem in a Bottle: Week 9

Week Nine

November 4, 2013

Water: The water in our ecosystem is still clear, and there is lots of condensation in the bottle.

Elodea: The elodea is still floating in the water. The oldest section of the elodea is now yellowing.

Snails: One of our snails is floating in the elodea. We think that this snail is probably deceased. The other snail is still stuck to the bottle near the bottom and looks alive.

Daphnia: The daphnia are still not visible, although any time the ecosystem bottle is moved, you can see tons of daphnia exoskeletons swirling around. That said, we haven't seen live daphnia since the second week.

Seeds/Leaves: All of our plants are brown or on their way to being brown. One of our bean plants is covered in a white, caterpillar-esque mold. 

Soil: The soil level is really low. There are two roots protruding from a bean plant. Our soil seems to be thoroughly depleted. Overall, our ecosystem seems to have run its course.