Woodland Ecology

Woodland Ecology

Tai Po Kau Nature Trail

IntroductionThe Tai Po Kau Nature Trail leads through a woodland and introduces some aspects of woodland ecology. Numbered marker-posts are placed at intervals along the trail to draw your attention to special features.

Q.1 What is a woodland or forest?

Stop no.1: Woodland light (light intensity) Q.2 Looking up and down, state

the changes in light intensity from tree top (canopy) to the ground.

Q.3 How is the vertical light gradient set up in forest? Will light gradient influence forest structure?

Stop no.2: Rainfall and stem flow Q.4 If it rains

while you are in a forest, will you experience the full force of the rain. Explain.

Q.5 State the importance of stem flow.

Stop no.3: Buttrees Roots Buttress roots are

spur-like swellings at the base of tree-trunk. They are common in forest trees.

Q.6 State the importance of buttress roots to trees.

Stop no.4: Liverworts, mosses and lichens

Q.7 Liverworts, mosses and lichens are very small “plants”. What taxonomic groups do they belong to?

Q.8 How can liverworts, mosses and lichens maintain water balance?

Stop no.5 Structure of the forest Q.9 State the plant groups according to their height in the vertical profile?Q.10 The phenomenon of vertical distribution of plants into layers is known as layering or stratification. What is the main physical factor that governs stratification? State ONE adaptive feature of under-storey plants.

(photo taken from display board of stop no.5)

Stop no.6: Colonizing a dead tree Q.11 What kinds

of organisms are found on or inside the dead tree?

Q.12 What is the importance of dead tree to the ecology of forest?

Stop no.7: Epiphytes

Epiphytes are plants that grow on trees without having roots in the soil. They are commonly found in forest.

Stop no.7: Epiphytes Q.13Are epiphytes parasitic? Q.14 State TWO advantage

s for plants to be epiphytic. Q.15 The water supply of e

piphytes is erratic (occasional rainfall + water held by bark is small). State THREE xerophytic features of epiphytes.

Q.16 Rough bark often have more epiphytes than smooth bark. Explain.

Stop no.8: Rocks and trees Q.17 Find a

large rock with plants growing on it. Why do most plants grow in cracks on the rock surface?

Stop no.9: Tree competition Q.18 In an

established forest, seedlings on the ground can seldom survive or grow to full size. Explain.

Q.19 When a tree falls (say, as a result of lightning), seedlings will develop quickly. Explain.

Stop no.10: Succession Succession refers to the changes of plant co

mmunity in an ecosystem over time. Q.20 Succession may start from bare rock

(primary succession) to form a forest. State the sequence of dominant plants developed.

Q.21 What are the events that may interrupt/retard primary succession?

Q.22 After a hillfire, what kind of plants will colonize the area first?

Stop no.11 Forest litter Forest litter is dead

remains of plants (tree trunk, twigs, leaves, flowers, seeds, etc.).

Q.23 Forest litter is a rich source of humus. State THREE functions of humus in forest.

Stop no.13: Plantation forest Q.24 How can you

determine whether the forest you are observing is an artificial plantation?

Q.25 What are the advantages of artificial plantation?

Review Questions 1. State TWO most important physical

factors that govern the abundance of plant species in forest.

2. State THREE common resources that plants are competing.

3. State various forms of adaptive features for forest plant species.

4. Apart from the plant species we have examined, forest includes a complex community of both plants and animals. Construct a food web with at least six organisms to show the trophic relationship within a forest.

Our field trip is only a qualitative study of forest. Suppose that we are going to have a quantitative study, suggest a suitable method for sampling. How?