6 CO2 + 12 H2O ---LIGHT + chlorophyll ---> C6H12O6 + 6 O2 + 6 H2O

GLOBE Carbon Cycle Plant-A-Plant: Hands-on Photosynthesis Experiments What Do the Plants Need to Grow?Abstract: The Plant-A-Plant Activity is under development as a part of the Carbon Cycle Project. Plants constitute a very important part of the global carbon cycle representing a large carbon pool in their biomass. This activity is designed for exploration and validation of necessity of sources determining plant growth and it demonstrates that CO2 is incorporated into plant biomass. It will help students to understand how the plants grow and what resources they need for their growth and biomass accumulation.Currently, our team is focused on the development of hands-on experiments in which students cultivate their own plants, while manipulating environmental conditions. By changing access to essential resources such as atmospheric carbon dioxide, water, light or mineral nutrition, experimental observations of plant requirements can be made. The first set of verified experiments is available for testing by pilot schools.Plant-a-Plant Objectives

Activity will lead students to:

Formulate their own hypotheses about plant growth and effects of different sources on it Conduct experiments based on given informationRecord observations and measurements Evaluate obtained dataMake conclusions based on obtained data and evaluate the validity of the original hypothesesExperiment 4 MINERAL NUTRIENTSExperiment 3 WATERExperiment 1 - CARBON DIOXIDEExperiment 2 LIGHTAffiliation: 1 - Charles University in Prague, Faculty of Science, Department of Plant Physiology, Prague, albrecht@natur.cuni.cz, CZ; 2 - TEREZA Association, Prague, CZ; 3 - University of New Hampshire, Durham, NH, USA; 4 GLOBE Program, Regional Consortia Coordinator and Carbon Cycle Project Lead, University Corporation for Atmospheric Research (UCAR), Boulder, CO, USAStudents explore, how the amount of CO2 affects maize growth. The amount of CO2 is given by the air volume in the plastic bottle in which the plant is cultivated. To one set of the bottles we add small tube or vial containing absorbent of CO2 (sodium hydroxide), which will reduce the carbon dioxide supply. Students then observe the plant size, color of the leaves, and compare the increase in plant dry weight between two treatments.

Length of the experiment:7 days seed germination14 days cultivation1-2 days harvest, dryingSuggested questions:How much CO2 does the air contain?Where and how is CO2 stored in a plant body?Do the roots need CO2 as well as leaves?Students explore, how the amount of water affects the growth of maize. They plant maize within two water suply treatments: 150 ml and 300 ml. Students observe the plant size and time until the plant has consumed the given water supply. Students harvest plants as soon as they become dry. The increase of plant dry weight is then compared between treatments. The experiment includes one control container without plants to account for simple evaporation.Suggested questions:Are pure water and air sufficient sources for the plant growth?Are the plants able to intake water by the leaves from the air?In this experiment students explore how the absence of light affects maize growth. Students observe the plant size, color of the leaves and and assess the increase of plant dry weight over time. One set of plants is planted in full daylight, the other set of plants is covered to prevent light access. Suggested questions:What does the light supply to a plant?Must plants have sunlight, exclusively?Length of the experiment:7 days seed germination11 days cultivation1-2 days harvest, dryingIn this experiment students consider how the absence or addition of essential nutrients affects the growth of maize. Different dose of the complex commercial fertilizer Cristalon is applied to plants. Students observe the plant size, presence of nutrient-deficiency symptoms such as leaf yellowing, and assess the increase of plant dry weight over time. After the harvest, in addition to dry weight of whole plants, students compare the root : shoot ratio for plants treated with different nutrient supplies.Suggested questions:What is the minimal amount of supplied nitrogen salt sufficient for plant to produce 1 kg of biomass?Are any of the biogenous elements more important than the others?Is the content of nutrients in soil / cultivation solution important for plants?Prospects and Plans:oThe pilot set of the present experiments is going to be tested by 10 pilot schools in the U.S. and 10 in the Czech Republic during 2007/2008.oDevelopment of supporting texts and materials.oNew additional experiments of all 4 types are going to be designed and verified for different levels of difficulties during 2007/2008.Different concentrations of complex fertilizer Acknowledgement: NSF GLOBE award 0627916, Exploring Ecosystems and the Atmosphere in the K-12 Classroom: A Plan to Integrate NASA Carbon Cycle Science with GLOBE Thanks for technical help to Drahomra Bartkov, Elena Kozlov, Jana Hubkov, Kateina ihkov.NitrogenCalciumMagnesiumWATERSUN

Graf1

0.009116250.00669444440.00075928860.00075928860.00030291790.0003029179

0.00636791670.00537777780.00038108850.00038108850.00009477070.0000947707

0.01548416670.01207222220.00108418040.00108418040.00026994510.0002699451

a

a

a

b

b

b

Control

CO2 deprived

Dry weight (g)

List1

Experiment 16 vliv CO2, uzaven ndoby, kukuice bez obilek II:

Szeno 11.6.2007; odbr 25.6.2007, tj. 14 dn kultivace, kukuice bez obilek, 6 rostlin vndob (sklzeny jako

jedno opakovn), 4 opakovn na variantu, vechny ndoby stejn velk (1 l), 3 varianty:

1. kontrola

2. 2 g NaOH

3. 10 obilek o znm hmotnosti, kter byly ponechny naklit a nsledn umstny do sku zern netkan

textilie - teoreticky by ve tm mly jen dchat a tak bt zdrojem CO2 pro 6 rostlin rostoucch na svtle

nettoprmry

prtkoenyobilkaFW (g)DW (g)R/SFWDWR/S

variantalhevpoet rostlinalobalFW+alDW+alalobalFW+alDW+alalobalFW+alDW+alvariantaprtkoenyobilkaprt+koenyprtkoenyobilkaprt+koenyFWDWprtkoenyobilkaprt+koenyprtkoenyobilkaprt+koenyFWDW

kontrola160.62321.7680.67860.56491.23430.6043kontrola0.19080.11160.00000.30240.00920.00660.00000.01580.58470.7112kontrola0.18710.1058487500.29290.00910.006367916700.01550.56570.7002513136

250.49441.36440.53460.44370.93930.47360.17400.09910.00000.27310.00800.00600.00000.01400.56970.7438NaOH0.14780.093861111100.24170.00669444440.005377777800.01210.63728329780.8046076697

340.55851.27850.5960.51340.90650.53790.18000.09830.00000.27830.00940.00610.00000.01550.54600.6533

460.62831.84910.68720.6221.30860.66280.20350.11440.00000.31790.00980.00680.00000.01660.56240.6927

0.01295599390.008347203300.0209742370.00075928860.000381088500.00108418040.01610151920.0377396909

NaOH160.45611.39670.49830.51081.09190.5429NaOH0.15680.09690.00000.25360.00700.00540.00000.01240.61780.76070.00977643140.005868378900.01036249020.00030291790.000094770700.00026994510.06583675620.0447536989

260.59541.41970.63410.53911.12490.5720.13740.09760.00000.23500.00640.00550.00000.01190.71070.8501

310.37890.52820.38550.34860.43570.35390.14930.08710.00000.23640.00660.00530.00000.01190.58340.8030shootrootwhole plant

4Control0.009116250.00636791670.0154841667

CO2 deprived0.00669444440.00537777780.0120722222Statistika

0.00075928860.00038108850.0010841804

0.00030291790.00009477070.0002699451

Statistika: Tukey-Kramer Multiple-Comparison Test

cel rostlina (FW)Different

GroupCountMeanFrom Groups

NaOH30.2416667kontrola

kontrola40.292925NaOH

cel rostlina (DW)Different

GroupCountMeanFrom Groups

NaOH31.21E-02kontrola

kontrola40.015475NaOH

R/S (FW)DifferentR/S (DW)Different

GroupCountMeanFrom GroupsGroupCountMeanFrom Groups

kontrola40.5657kontrola40.70025NaOH

NaOH30.6373NaOH30.8046kontrola

List1

000.01295599390.01295599390.00977643140.0097764314

000.00834720330.00834720330.00586837890.0058683789

000000

kontrola

NaOH

erstv hmotnost

List2

000.00075928860.00075928860.00030291790.0003029179

000.00038108850.00038108850.00009477070.0000947707

000000

kontrola

NaOH

such hmotnost

List3

000.01610151920.01610151920.06583675620.0658367562

000.03773969090.03773969090.04475369890.0447536989

kontrola

NaOH

R/S pomr

000.0209742370.0209742370.01036249020.0103624902

kontrola

NaOH

cel rostlina (erstv hmotnost)

000.00108418040.00108418040.00026994510.0002699451

kontrola

NaOH

cel rostlina (such hmotnost)

000.00075928860.00075928860.00030291790.0003029179

000.00038108850.00038108850.00009477070.0000947707

000.00108418040.00108418040.00026994510.0002699451

a

a

a

b

b

b

Control

CO2 deprived

Dry weight (g)