Forest Structure and Composition

Courses : Forest Ecology Lecturer : Bella Ariana Semester : 4th Semester, 2022/2023 Sesion Forest Structure and Composition Forest structure is a term that refers to the physical arrangement and organization of plants in the forest. The forest structure consists of canopy, middle and lower layers. The middle layer consists of the shorter trees and shrubs, while the canopy layer consists of the trees that form the roof of the forest. Low plants, shrubs and grasses are located on the lower layer. In each layer, the forest structure creates a different microenvironment. This impacts lighting, temperature, humidity, and available resources. Forest composition refers to the types of trees and other creatures that live in the forest. The diversity of tree species, population density, spatial distribution, and communities of organisms such as mosses, ferns, epiphytes, fungi, insects, mammals, birds, and reptiles are the components that make up the forest structure. Forest composition varies geographically and is influenced by climate, soil type and natural history. Forest structure and composition influence each other and affect the sustainability of the ecosystem. High biodiversity, balanced nutrient cycles and ecosystem balance can be achieved through good structures rich in species. To ensure the preservation of biodiversity and the sustainable management of forests, it is very important to understand how forests are constructed and what they consist of. Trees that grow tightly and interrelated define a forest as an ecosystem. Forest structure and composition vary depending on forest type and environmental conditions. However, forests usually consist of several main layers, such as the underlayer, middle layer, and canopy. 1. Canopy layer: The layer of trees that forms the roof of a forest is called the canopy. Trees in the canopy layer are often tall with lots of leaves, so they catch most of the sunlight and hold moisture. Since sunlight is limited to reach the lower layer, the canopy layer creates a different microenvironment below. The following are examples of canopy layers in a forest: • The canopy layer of tropical rain forests usually consists of tall trees such as teak (Tectona grandis), merbau (Intsia spp.), lime (Shorea spp.), and meranti (Shorea spp.). These trees form a covered forest roof with dense crowns and dense fronds. • The canopy layer in a coniferous forest, such as a boreal forest or montane forest, is made up of conifer trees such as fir, pine, and spruce. These trees have dense branches and branches and a thick canopy of needle-shaped leaves. • The canopy layer of mixed forests, such as forests in temperate regions, is composed of a combination of broadleaf and conifer trees. Mixed oak, maple, birch, and fir are examples. 2. Middle layer: The middle layer consists of the shorter trees and shrubs below the canopy layer. Trees in the middle layer receive more sunlight than those in the lower layers, but less than those in the canopy. In the middle layers of the forest, several plant species such as shrubs, palms and shade-tolerant trees are often found. The following are examples of the middle layers of the forest: • The middle layer of forest in tropical rainforests may consist of shorter trees such as fig trees (Ficus spp.), oil palm trees (Elaeis guineensis), and cypress trees (Casuarina spp.). The middle layer also often contains vines such as wild orchids (Orchidaceae) and shrubs such as pandanus (Pandanus spp.). • Shallow trees such as alder bushes (Alnus spp.), horsetail trees (Ephedra spp.), and berry bushes (Vaccinium spp.) can be found in the middle layers of coniferous forests. In the middle layers, some shade-tolerant shrub species, such as huckleberries (Gaylussacia spp.), can also be found. • In mixed forests, the middle layer may consist of trees such as maples (Acer spp.), oaks (Quercus spp.), ash trees (Fraxinus spp.), and birch trees (Betula spp.). The middle layer may also consist of shrubs such as azaleas (Rhododendron spp.), salal (Gaulttheria shallon), and viburnum (Viburnum spp.). 3. Understorey: The lowest layer in the forest is the understorey, which consists of low growth plants, shrubs, grasses, and pioneer plants that grow in an open environment. Because the canopy and mid layers block it, the under layers receive little sunlight. Plants in the lower layers of the forest often compete for limited resources. The following are examples of the middle layers of the forest: • The middle layer of forest in tropical rainforests may consist of shorter trees such as fig trees (Ficus spp.), oil palm trees (Elaeis guineensis), and cypress trees (Casuarina spp.). The middle layer also often contains vines such as wild orchids (Orchidaceae) and shrubs such as pandanus (Pandanus spp.). • Shallow trees such as alder bushes (Alnus spp.), horsetail trees (Ephedra spp.), and berry bushes (Vaccinium spp.) can be found in the middle layers of coniferous forests. In the middle layers, some shade-tolerant shrub species, such as huckleberries (Gaylussacia spp.), can also be found. • In mixed forests, the middle layer may consist of trees such as maples (Acer spp.), oaks (Quercus spp.), ash trees (Fraxinus spp.), and birch trees (Betula spp.). The middle layer can also consist of shrubs such as azaleas (Rhododendron spp.), salal (Gaulttheria shallon), and viburnum (Viburnum spp.). In mangrove forests, the middle layer can be filled with trees such as the fire mangrove (Rhizophora mucronata). ), red mangrove trees (Bruguiera gymnorrhiza), and black mangrove trees (Avicennia germinans). Ferns and small shrubs can also be found in the middle layer of the mangrove forest. The composition of the forest, in addition to its structure, refers to the types of trees and animals present in it. Forest composition varies greatly depending on geographic location and other environmental factors. One tree species may dominate some forests, while many forests contain many different tree species. Non-tree organisms, such as mosses, ferns, epiphytes, fungi, insects, mammals, birds and reptiles, may also be included in the forest composition. These organisms assist in various ecosystem functions, including plant pollination, seed dispersal, organic matter decomposition, and the food chain, apart from playing an important role in maintaining the balance of the forest ecosystem. Therefore, the structure and composition of forests are interrelated and create a diversity of ecosystems, which is very important for the sustainability and health of forests. .