Quantitative Analysis of Three Ecosystems for Leaving Certificate Biology

Transcription

1 Quantitative Analysis of Three Ecosystems for Leaving Certificate Biology Co.Wexford Education Centre Teacher Design Team Catherine Doyle Louise Murphy Pat O Leary Margaret O Neill

2 Contents Introduction Page 3 The Rocky Seashore Page 6 The Woodland Page 15 The Grassland Page 21 Acknowledgements We would like to acknowledge the support of the Biology Support Service. We would also like to extend our appreciation to Co. Wexford Education Centre for the provision of their facilities. Finally our thanks go to the principals of the following schools for their understanding and support. Gorey Community School. Bunclody Vocational College. Loreto Secondary School, Wexford. F.C.J. Secondary School, Bunclody. 2

3 Introduction This booklet has been designed with a view to providing help for teachers with the practical part of the Ecology section of the Leaving Certificate Biology syllabus. Three ecosystems, woodland, grassland and the rocky seashore were selected as representative of the many available for study. Five plants and five animals were chosen for each ecosystem and both Latin and common names as well as photos are included for all organisms. Tables with sample figures are provided to allow for calculation of percentage frequency, percentage cover and population density. A sample calculation for each is also included, accompanied by a graphical representation of results. Animals Many animals in the woodland and grassland ecosystems can easily be missed because they hide or move away when approached. In order to identify these animals and to carry out a quantitative study it is necessary to capture them by: Mammal trap Pitfall trap Insect net Pooter 3

4 Capture Recapture Method Once captured the animals should be counted and then marked in such a way as not to endanger them or inhibit their activity. The captured animals are released near to where they were captured. A second visit is necessary. On the second visit the captured animals are counted as before and the number of marked animals that were recaptured is noted. The following formula gives an approximation of the total population of that animal in that ecosystem. Total Population = No. of animals caught on 1 st visit x No. of animals caught on 2 nd visit No. of marked animals recaptured on the 2 nd visit Sample Calculation Total Population Field mouse Number of animals caught and marked on 1 st visit = 20 Number of animals caught on 2 nd visit =15 Number of marked animals caught on 2 nd visit = 5 Total population = 20 x 15 =

5 Plants In carrying out the percentage cover or population density study of certain plants it must be decided before the field trip how the plants are to be counted. Example Ivy/Bramble If several branches of the same plant are inside the quadrat is each one counted as one plant? Do you source the root of the plant and count that as one plant? What if the root is outside the quadrat? A decision on these types of questions should be agreed upon and understood by all students involved in the study so as to ensure the collection consistent data and keep human error to a minimum. 5

6 The Rocky Seashore 6

7 Seashore Introduction For the study of the rocky seashore ecosystem we chose an area of study 50m from upper to lower shore, 60m wide. This gave a total area of 3000m 2. A belt transect was laid out and 10 quadrats were placed at 5m intervals along its length. We have included a percentage cover study for the seashore animals since many of them remain in situ. Quadrats of side 0.5m were used to collect data for frequency and population density tables. 0.5m Quadrat Grid quadrats were used for percentage cover tables. 0.5m Grid Quadrat The five plants (flora) and five animals (fauna) chosen are shown below. 7

8 Flora and fauna of the seashore Bladder Wrack Fucus vesiculosis Limpet Patella vulgata Sea Lettuce Ulva lactuca Sea Anemone Urticina felina Gutweed Enteromorpha intestinalis Barnacles Chthamalus stellatus Serrated Wrack Fucus serratus Dog Whelk Nucella lapillus Eggwrack Ascophyllum nodosum Edible Periwinkle Littorina littorea 8

9 Percentage Frequency Seashore Plants The presence or absence of each plant is recorded for each quadrat as shown in the table below. Plant Quadrat Number Total % Frequency Bladder wrack Fucus vesiculosus x x x 7 70 Sea lettuce Ulva lactuca x x x x x x x 3 30 Gut weed Enteromorpha intestinalis x x x x x x x 3 30 Egg wrack Ascophyllum nodosum x x x x x 5 50 Serrated wrack Fucus serratus x x x x x x 4 40 Sample Calculation: Percentage Frequency of Bladder wrack 1. Count the number of quadrats in which the plant is present = Divide by number of quadrats to get frequency 7/10 = Multiply by 100 to get % frequency 0.7 x 100 = 70% % Frequency Seashore Plants Plants Bladder wrack Sea lettuce Gut weed Egg wrack Serrated wrack 9

10 Percentage Frequency Seashore Animals The presence or absence of each animal is recorded for each quadrat as shown in the table below. Animal Quadrat Number Total % Frequency Limpets Patella vulgata x x x x x 5 50 Sea Anemone Urticina felina x x x x x x x x 2 20 Barnacles Chthamalus stellatus x x x x x 5 50 Dog whelk Nucella lapillus x x x x x x 4 40 Edible periwinkle Littorina littorea x x x x 6 60 Sample Calculation: Percentage Frequency of Limpets 1. Count the number of quadrats in which the animal is present. = Divide by total number of quadrats to get frequency. 5/10 = Multiply by 100 to get % frequency. 0.5 x 100 = 50% % Frequency Seashore Animals Animals Limpets Sea Anemone Barnacles Dog Whelks Edible Periwinkle 10

11 Percentage Cover Seashore Plants A hit point is chosen in each square of the grid quadrat e.g. the point of intersection of the vertical and horizontal lines. A pen is placed at this point and if it touches an organism it is recorded as a hit for that organism. In a 5x5 quadrat the maximum number of hit points is 25. This procedure is repeated for each of the 10 quadrats and figures recorded as shown in the table below. Plant Quadrat Number Total Hits % Cover Bladder wrack Fucus vesiculosus Sea lettuce Ulva lactuca Gut weed Enteromorpha intestinalis Egg wrack Ascophyllum nodosum Serrated wrack Fucus serratus Sample Calculation: Percentage Cover of Sea Lettuce 1. Count total number of hits Divide by total number of possible hits. 9/250 = Multiply by 100 to get percentage cover x 100 = 3.6% % Cover Seashore Plants Bladder wrack Sea lettuce Gut weed Egg wrack Serrated wrack 11

12 Percentage Cover Seashore Animals A hit point is chosen in each square of the grid quadrat e.g. the point of intersection of the vertical and horizontal lines. A pen is placed at this point and if it touches an organism it is recorded as a hit for that organism. In a 5x5 quadrat the maximum number of hit points is 25. This procedure is repeated for each of the 10 quadrats and figures recorded as shown in the table below. Animal Quadrat Number Total Hits % Cover Limpets Patella vulgata Sea Anemone Urticina felina Barnacles Chthamalus stellatus Dog whelk Nucella lapillus Edible periwinkle Littorina littorea Sample Calculation: Percentage Cover of Barnacles 1. Count total number of hits Divide by total number of possible hits. 32/250 = Multiply by 100 to get percentage cover x 100 = 12.8% % Cover Seashore Animals Limpet Sea Anemone Barnacles Dog Whelk Edible Periwinkle 12

13 Population Density Seashore Plants The number of each plant in each quadrat is counted and recorded as in the table below. Plant Quadrat Number Total Average Density (no./m 2 ) Bladder wrack Fucus vesiculosus Sea lettuce Ulva lactuca Gut weed Enteromorpha intestinalis Egg wrack Ascophyllum nodosum Serrated wrack Fucus serratus Sample Calculation of Population Density for Gutweed: 1. Count the total number and divide by 10 to get the average. 26/10 = Calculate the area of the quadrat 0.5m x 0.5m = 0.25m 2 (i.e.4 quadrats per m 2 ) 3. To calculate the density, multiply the average by x 4 = 10.4 animals per m 2 4. To calculate the total population, multiply the density by the area of the ecosystem: 10.4 plants/m 2 x 3000 m 2 = plants Number of Plants Population Distribution Seashore Plants Quadrat Number Bladder wrack Fucus vesiculosus Sea lettuce Ulva lactuca Gut weed Enteromorpha intestinalis Egg wrack Ascophyllum nodosum Serrated wrack Fucus serratus 13

14 Population Density Seashore Animals The number of each animal in each quadrat is counted and recorded as in the table below. Animal Quadrat Number Total Average Density (no./m 2 ) Limpets Patella vulgata Sea Anemone Urticina felina Barnacles Chthamalus stellatus Dog whelk Nucella lapillus Edible periwinkle Littorina littorea Sample Calculation Population Density Dog Whelk 1. Count the total number and divide by 10 to get the average. 25/10 = Calculate the area of the quadrat 0.5m x 0.5m = 0.25m 2 (i.e.4 quadrats per m 2 ) 3. To calculate the density multiply the average by x 4 = To calculate the total population, multiply the density by the area of the ecosystem: 10 animals/m 2 x 3000 m 2 = animals Population Distribution Seashore Animals Number of Animals Quadrat Number Limpets Patella vulgata Sea Anemone Urticina felina Barnacles Chthamalus stellatus Dog whelk Nucella lapillus Edible periwinkle Littorina littorea 14

15 The Woodland 15

16 Woodland Introduction An area of study measuring 25m x 50m was marked off. This gave a total area of 1250 m 2. Ten quadrats were chosen at random and data recorded for percentage cover, percentage frequency and population density as outlined in the tables below. Quadrats of side 0.5m were used to collect data for frequency and population density tables. 0.5m Quadrat Grid quadrats were used for percentage cover tables. 0.5m Grid Quadrat The five plants (flora) and five animals (fauna) chosen are shown below. 16

17 Flora and fauna of the woodland Wild Garlic Allium ursinum Earthworm Lumbricus terrestris Bluebell Hyacinthoides non-scripta Woodlouse Armadillidium vulgare Wood Sorrel Oxalis acetosella Devils Coach-horse Staphylinus olens Primrose Primula vulgaris Harvestman Phalangium opilio Lesser Celandine Ranunculus ficaria Ladybird Coccinella septempunctata 17

18 Percentage Frequency Woodland Plants The presence or absence of each plant is recorded for each quadrat as shown in the table below. Plant Quadrat Number Total % Frequency Bluebell Hyacinthoides non-scripta X X X X X 5 50 Wood sorrel Oxalis acetosella X X X X X 5 50 Wild garlic Allium ursinum X X X X X 5 50 Primrose Primula vulgaris X X X X X 5 50 Lesser celendine Ranunculus ficaria X X X 7 70 Sample Calculation: Percentage Frequency of Primrose 1. Count the number of quadrats in which the plant is present = Divide by total number of quadrats to get frequency. 5/10 = Multiply by 100 to get % frequency. 0.5 x 100 = 50% % Frequency Woodland Plants Plant Bluebell Wood Sorrel Wild Garlic Primrose Lesser Celendine 18

19 Percentage Cover Woodland Plants A hit point is chosen in each square of the grid quadrat e.g. the point of intersection of the vertical and horizontal lines. A pen is placed at this point and if it touches an organism it is recorded as a hit for that organism. In a 5x5 quadrat the maximum number of hit points is 25. This procedure is repeated for each of the 10 quadrats and figures recorded as shown in the table below. Plant Quadrat Number Total Hits % Cover Bluebell Hyacinthoides non-scripta Wood Sorrel Oxalis acetosella Wild Garlic Allium ursinum Primrose Primula vulgaris Lesser celendine Ranunculus ficaria Sample Calculation: Percentage Cover Bluebell 1. Count total number of hits. = Divide by total number of possible hits. 56/250 = Multiply by 100 to get percentage cover x 100 = 22.4% Percentage cover Woodland Bluebell Wood Sorrel Wild Garlic Primrose Lesser Celendine 19

20 Population Density Woodland Plants The number of each plant in each quadrat is counted and recorded as in the table below. Plant Quadrat Number Total Average Density (no./m 2 ) Bluebell Hyacinthoides non-scripta Wood Sorrel Oxalis acetosella Wild Garlic Allium ursinum Primrose Primula vulgaris Lesser celendine Ranunculus ficaria Sample Calculation of Population Density for Wild Garlic 1. Count the total number and divide by 10 to get the average. 10/10 = 1 2. Calculate the area of the quadrat 0.5m x 0.5m = 0.25m 2 3. To calculate the Density: multiply the average by 4. 1 x 4 = 4 4. To calculate the total population, multiply the density by the area of the ecosystem: 4 plants/m 2 x 1250 m 2 = 5000 plants Population Distribution Woodland Plants Number of Plants Quadrat Number Bluebell Hyacinthoides nonscripta Wood Sorrel Oxalis acetosella Wild Garlic Allium ursinum Primrose Primula vulgaris Lesser celendine Ranunculus ficaria 20

21 The Grassland 21

22 Grassland Introduction An area of study measuring 25m x 50m was marked off. This gave a total area of 1250 m 2. Ten quadrats were chosen at random and data recorded for percentage cover, percentage frequency and population density as outlined in the tables below. Quadrats of side 0.5m were used to collect data for frequency and population density tables. 0.5m Quadrat Grid quadrats were used for percentage cover tables. 0.5m Grid Quadrat The five plants (flora) and five animals (fauna) chosen are shown below. 22

23 Flora and fauna of the grassland Dandelion Taraxacum officinale Woodlouse Armadillidium vulgare Plantain Plantago major Ladybird Coccinella septempunctata Daisy Bellis perennis Aphid Sitobian avenae Rye Grass Lolium perenne Earthworm Lumbricus terrestris Clover Trifolium repens Slug Deroceras reticulatum 23

24 Percentage Frequency Grassland Plants The presence or absence of each plant is recorded for each quadrat as shown in the table below. Plant Quadrat Number Total % Frequency Daisy Bellis perrenis x x x x 6 60 Dandelion Taraxacum officinale x x x x 6 60 Plantain Plantago major x x x 7 70 Clover Triflolium repens Grass Lolium perenne Sample Calculation: Percentage Frequency of Plantain 1. Count the number of quadrats in which the plant is present. = 7 2. Divide by total number of quadrats to get frequency. 7/10 = Multiply by 100 to get % frequency. 0.7 x 100 = 70% % Frequency Grassland Plants Daisy Dandelion Plantain Clover Grass 0 Plant 24

25 Percentage Frequency Grassland Animals The presence or absence of each animal is recorded for each quadrat as shown in the table below Animal Quadrat Number Total % Frequency Earthworm Lumbricus terrestris x x x x 6 60 Woodlouse Oniscus asellus x x x x x 5 50 Slug Deroceras reticulatum x x x 7 70 Sample Calculation: Percentage Frequency of Woodlouse 4. Count the number of quadrats in which the animal is present. = Divide by total number of quadrats to get frequency. 7/10 = Multiply by 100 to get % frequency. 0.7 x 100 = 70% % Frequency Grassland Animals Earthworm Woodlouse Slug Animal 25

26 Percentage Cover Grassland Plants A hit point is chosen in each square of the grid quadrat e.g. the point of intersection of the vertical and horizontal lines. A pen is placed at this point and if it touches an organism it is recorded as a hit for that organism. In a 5x5 quadrat the maximum number of hit points is 25. This procedure is repeated for each of the 10 quadrats and figures recorded as shown in the table below. Plant Quadrat Number Total Hits % Cover Daisy Bellis perrenis Dandelion Taraxacum officinale Plantain Plantago major Clover Triflolium repens Grass Lolium perenne Sample Calculation: Percentage Cover of Plantain 1. Count total number of hits. = Divide by total number of possible hits. 116/250 = Multiply by 100 to get percentage cover x 100 = 46.4% % Cover Grassland Plants Daisy Dandelion Plantain Clover Grass 26

27 Population Density Grassland Plants The number of each plant in each quadrat is counted and recorded as in the table below. Plant Quadrat Number Total Average Density (no./m 2 ) Daisy Bellis perrenis Dandelion Taraxacum officinale Plantain Plantago major Clover Triflolium repens Grass Lolium perenne Sample Calculation Population Density Dandelion 1. Count the total number and divide by 10 to get the average. 26/10 = Calculate the area of the quadrat 0.5m x 0.5m = 0.25m 2 3. To calculate the density multiply the average by x 4 = To calculate the total population, multiply the density by the area of the ecosystem: 10.4 plants/m 2 x 1250 m 2 = plants Population Distribution Grassland Plants 20 Number of Plants Quadrat Number Daisy Bellis perrenis Dandelion Taraxacum officinale Plantain Plantago major Clover Triflolian repens Grass Lolium perenne 27

28 Population Density Grassland Animals The number of each animal in each quadrat is counted and recorded as in the table below. Animal Quadrat Number Total Average Density (no./m 2 ) Earthworm Lumbricus terrestris Woodlouse Oniscus asellus Slug Deroceras reticulatum Sample Calculation Population Density Earthworm 1. Count the total number and divide by 10 to get the average. 18/10 = Calculate the area of the quadrat 0.5m x 0.5m = 0.25m 2 3. To calculate the density, multiply the average by x 4 = To calculate the total population, multiply the density by the area of the ecosystem: 7.2 animals/m 2 x 1250 m 2 = 9000 animals Population Distribution Grassland Animals Number of Animals Quadrat Number Earthworm Lumbricus terrestris Woodlouse Oniscus asellus Slug Deroceras reticulatum 28