Bettina Keller. Janet Kerkulah. Ingvild Råmunddal. Åsta Rønning Omholt. Vest-Telemark vidaregåande skule. Dalen, Norway

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1 Bettina Keller Janet Kerkulah Ingvild Råmunddal Åsta Rønning Omholt Vest-Telemark vidaregåande skule Dalen, Norway Teacher: Åse Kiland, Karl Torstein Hettland, Birgit Johanne Kovajord Olsnes

2 Abstract The following data concerning the threes and the forest have been collected by students. The purpose of this project is to explain the connections between climatic factors like rain and sun and the growth of the trees. We suggested that we could find out how the climate has been by analyzing the three rings and taking a special look at the length of the growing periods. 2

3 Research Questions and Hypothesis We explored small part of the forest near our school, which also happens to be near the river. We took samples of three different pines (the most spread tree type in Norway) and filed them so we could use for our research. A tree ring shows us how much a tree within a year. What kind of information can we get out of our samples? Our hypothesis: We can use the amplitude of the tree rings to tell how the climate in the particular year was. Every tree ring consists of two different parts. There is a bright part that is usually broader than the dark part. The simple reason for this is that the bright part stands for the growing season in spring and summer, and the dark one for winter and autumn. The growth period in summer and spring is much longer than in autumn and winter since conditions are much better. The weather is mostly well and the proportion between warmth and humidity is optimal for the growing, and the winter and autumn on the other hand. It is mostly cold, relatively dry, and the insolation is much lower. Therefore the trees photosynthetic activity is limited and the amount of produced biomass is low. Figure nr. 1, the area The forest vegetation was dominated by much pine and blueberry-bushes, and moss. The soil- profile shows podsol.the soil has a good draining-system. 3

4 Materials and Method Figure nr. 2 Norway, Telemark, Dalen (Huvestadfeltet) Figure nr. 3. Finding the forest and getting instructions To start our project we had to find a fitting forest first. The forest needed to be a forest where many pines grow. After we found a quite young forest near a river we got your instructions from our Naturfag ( that s like general nature science subject) teacher Åse. She told us how to use the borer and which trees we should pick. She also explained us how to measure the height of the trees. On the left side is a picture of the borer we use to collect the samples of the trees. Figure nr. 4 4

5 As you can see on the left side, we found a matching area (10m x10m). We marked the trees with orange tape so we could find them again later. Figure nr.5 Janet is measuring the area that we chose. It had to be a square of 10mx 10m, Figure nr.6 Figure nr.7 Åsta found a matching tree that seemed quite interesting. Figure nr.8 5

6 Figure nr.9, starting the work As you can see we found our trees. We chose three pines that were high, relatively young and healthy. After we had chosen and marked the trees we started measuring them. On the picture above you can see Ingvild and Bettina as they measure the circumference with a cord. We made to measurements from every tree. (One in breast height and one just above the root.) To measure the height of the tree we used the sentence of Pythagoras. Therefore we needed to measure to angles. The angles form the treetop to the ground and the angle of the ground to the root. To use the sentence of Pythagoras we still needed another parable, the distance of the person measuring to the tree. As we figured out this distance had to be around 10m for the measurement to be accurate. Figure nr.10 After measuring them and writing our results down we could compute the results in the classroom. On the left side you can see the device we used to measure the angles. We took the samples to the classroom and abraded them in order to see the tree rings even more clearly. Climate data (mm) and avaragetemperature ( C ) is taken from the Norwegian Meteorological institute for Norway. It shows us data for Tokke Kommune in the period of

7 There were different types of plants in the area we analyzed. There were dominated of pine-trees while blueberry heather and moss where dominated plants at the ground. The location for our site is on moraine and to study the soil horizons we made a soilprofile. We classified this to be a podzol (fig.11). Figure nr. 11, Soil profile and Vegetation analysis 7

8 Data Summary, Analysis and Results Tree nr.1: t Tree nr t Figure nr. 13, Skeleton Plot from our samples Comparison of the two samples : We can see that the samples show big differences in 1932 and generally in the nineteen thirties. While tree nr.1 hasn t really grown tree nr.2 grew quite a lot. This is rare since the 2 trees stood next to each other and are of the same kind. Also in the period between 1995 until 2010 we can see big diversity. The skeleton plot shows us that tree nr.2 had a bad growth but tree nr.1 had an average growth. This is not that strange since there is a piece of tree missing in the sample of tree nr.2. Therefore the sample is not as accurate as it should be. It is not a reliable source for data. What we can see is that the growth of both trees in the period from is not very different. There are only some small periods where they don t concur. 8

9 Comparison with another group We compered our samples with a group who took samples beside the river (group 3). Here are their samples: Tree nr t Tree nr t Tree nr t Figure nr. 14, Skeleton Plot from the site by the river It some differences between the samples. For example: While our trees had bad growth in 1984, their trees had good growth. It can be that our area had a lack of nutrient, and less sun. The other group was beside the river, and they had maybe better access of weather and nutrient. If we take a look at the year 2008 we can see that both our tree nr.1 and there tree nr.1 show a positive growth. It may seem that our tree 1. Had a much better growth than theirs but you have to consider that the rating (-5,+5) stands always in the proportion of a trees worst year and a trees best year. As you may see their tree never had a year with the rating -5. So they have smaller differences between the thickness of the tree ring, while we have big differences. A tree ring that was rated with a 2 on their skeleton mustn t be thicker than a tree ring that we rated with a 5. Therefor we can say that the growth of the trees might concur. 9

10 Analysis and Results According to our samples is tree number one 104 years old; tree number two 92 years old and tree number three 75 years old. Comparison of the Skeleton plot and the climate data Tree nr.1 I tried to choose years where I could see a very clear tendency for an either good or bad growth. I put the results in the table below. Year Precipitation (Sum/Year) Temperature (average) Growth of the tree mm 6.0 C Really bad growth ( -5) mm 6.3 C Quite good growth (+2) Result According to the data the tree should have shown a good growth. This is not the case. Reasons for that could be: a lack of nutrient in the soil, not enough sunlight or that the tree was not having enough space to grow. The data shows us a year with ideal conditions for the tree to grow. Nevertheless the tree shows not as good growing as we might expect when looking at the data. However we can say that the inconsistence between the data and the facts are not as big as in

11 mm 5. 0 C Really bad growth (-4) We have again an inconsistence of the data and the samples. The relatively warm year and the high amount of precipitation indicate a good growth. But as you can see the tree had a bad growing season. Reasons for that may be the same as in Tree nr.2 As with tree nr.1 I tried to analyze years that show either really good or really bad years. You can see the results in the table below. Year Precipitation (Sum /Year) Temperature (average) Growth of the tree mm 5.9 C Very good growth (+5) Results We can see in the clima data that there was not really much precipitation but that it was a quite warm year. Even though the amount of precipitation wasn t that big the tree grew a lot. This might indicate that this kind of tree (pine) does neither need nor prefer a wet clima. That would be weird since the clima in Norway is generally not that dry. Therefor I 11

12 mm 5.0 C Quite bad growth (-3) mm 4.1 C Very bad growth (-4) Figure nr. 15 would say that our results don t accord with the data. If you just take a look at the clima data you can see that this year was neither especially warm nor moist. Therefor the trees growth should have been bad or even really bad. If you now see how it actually was you can see that the tree really didn t grow much. You can therefore say that the clima data and the data from the samples agree with each other. According to the clima data the growth of the tree should have been bad. The tree sample shows in analogy a bad growth. The cold rather dry climate prevented the tree from growing as much as usual. 12

13 Conclusions It was difficult to contest as well as to approve hypothesis because of the bad quality of our samples. But we can still say that there were periods with bad conditions for the tree to grow. But we cannot say in which years. We had also false year rings in our samples and thin periods with bad growth. The tree rings were really close so it was difficult to decide weather they showed the growth of a whole year or if they were false year rings. We had also problems because small pieces of the samples were missing. 13

14 References Skelton Plotting by Andreas Kirchhefer 14

15 Appendix Vegetasjonsanalyse-skjema Naturtype: Sted: Huvestad Dato: (Dominerende: xxx Vanlig: xx Sjelden: x) Naturtype: Artsliste Furu XXX Gran Einer Tyttebær Blåbær Krekling Røsslyng Linnea Skrubbær Skogstjerne Hvitveis Maiblom Tepperot Gaukesyre Gullris Småmarimjelle Nikkevintergrønn Smyle Engkvein Bjønnkam Hengeving Fugletelg Torvmose Fjærmose Sigdmose Bjørnemose Etasjehusmose Furumose Stiv kråkefot Andre arter: Rogn Grass Etasjemose Liljekonval Treskikt: over 2 meter Busksjikt opp til 2 meter Feltskikt: urter, gras, lyng X XXX X X X XX XXX XX Botnskikt: mose, lav XX XX XXX XXX X 15

16 Tre Nr. Lengd egrad (Ø) Bredd egrad (N) Omk rins ved rota O (cm) 1.0 7m 1.3 3m 1.0 2m Omk rins i bryst høgd e O (cm) 85c m 1.0 5m Diam eter O/3, cm cm 1m cm Horis ontal avsta nd til tre A (m) Vin kel 1 v1 2m 73 gr ad er 2m 62 gr ad er 2m 70 gr ad er Høgd e 1 h1 A*tan v m 3.76 m 5.49 m Vinkel 2 v2 22 grader 26 grader 18 grader Høgde 2 h2 A*tan v2 o.80 m 0.97 m 0.64 m Total høgde h1+h2 7.34m 4.73 m 6.30 m 16