Human Impacts on Deciduous Forest

Autumn Blaze Maple Tree

The autumn blaze maple tree is a unique combination of good traits from the red maple and silver maple. The qualities mixed by the autumn blaze maple tree are brilliant orange-red color in the fall, dense and healthy branching, and enhanced growth that protects from insects and disease. They are known for their unexcelled speed of growth. The autumn blaze maple tree can also live in a variety of climates, ranging from the frigid cold of zone three, to the humid south of zone eight.

The autumn blaze maple tree will grow to fifty or sixty feet tall and have a mature spread of thirty to forty feet. They are not a susceptible to storm damage as the silver maple, as they received stronger wood from their red maple parent. The autumn blaze maple tree also has the ability to grow in most soil conditions.

The leaves of the autumn blaze maple tree resemble the leaves of a silver maple tree, being opposite, simple, and five-lobed with toothy margins. The deep red veins of the leaves are derived from the red maple. The summer color of the autumn blaze maple tree is a rich medium green, which turns into orange and crimson in the fall. The leaves of the autumn blaze maple tree will last longer on the branch than those of other maple trees.

The Birch

Birch species are generally small to medium-sized trees or shrubs, mostly of temperate climates. The simple leaves are alternate, singly or doubly serrate, feather-veined, petiolate and stipulate. They often appear in pairs, but these pairs are really borne on spur-like, two-leaved, lateral branchlets. The fruit is a small samara, although the wings may be obscure in some species. They differ from the alders (Alnus, other genus in the family) in that the female catkins are not woody and disintegrate at maturity, falling apart to release the seeds, unlike the woody, cone-like female alder catkins.

The bark of all birches is characteristically marked with long, horizontal lenticels, and often separates into thin, papery plates, especially upon the paper birch. It is resistant to decay, due to the resinous oil it contains. Its decided color gives the common names gray, white, black, silver and yellow birch to different species.

European larch

Larix decidua, common name European larch, is a species of larch native to the mountains of central Europe, in the Alps and Carpathian Mountains, with also low populations in southern Poland and southern Lithuania.

Larix decidua is a medium-size to large deciduous coniferous tree reaching 25-45 m tall, with a trunk up to 1 m diameter (exceptionally, to 55 m tall and 2 m diameter). The crown is conic when young, becoming broad with age; the main branches are level to upswept, with the side branches often pendulous. The shoots are dimorphic, with growth divided into long shoots (typically 10-50 cm long) and bearing several buds, and short shoots only 1-2 mm long with only a single bud. The leaves are needle-like, light green, 2-4 cm long which turn bright yellow before they fall in the autumn, leaving the pale yellow-buff shoots bare until the next spring.

The cones are erect, ovoid-conic, 2-6 cm long, with 30-70 erect or slightly incurved (not reflexed) seed scales; they are green variably flushed red when immature, turning brown and opening to release the seeds when mature, 4-6 months after pollination. The old cones commonly remain on the tree for many years, turning dull grey-black.It is very cold tolerant, able to survive winter temperatures down to at least -50°C, and is among the tree line trees in the Alps, reaching 2400 m altitude, though most abundant from 1000-2000 m. It only grows on well-drained soils, avoiding waterlogged ground.

Deciduous forest animals

A wide variety of mammals, birds, insects, and reptiles can be found in a deciduous forest biome. Mammals that are commonly found in a deciduous forest include bears, raccoons, squirrels, skunks, wood mice, and in the U.S., deer can be found in these forests. While bobcats, mountain lions, timber wolves, and coyotes are natural residents of these forests, they have nearly been eliminated by humans because of their threat to human life. Other animals that were native to this biome, such as elk and bison, have been hunted to near extinction.

Migration and hibernation are two adaptations used by the animals in this biome. While a wide variety of birds migrate, many of the mammals hibernate during the cold winter months when food is in short supply. Another behavioral adaptation some animals have adopted is food storage. The nuts and seeds that are plentiful during the summer are gathered by squirrels, chipmunks, and some jays, and are stored in the hollows of trees for use during the winter months. Cold temperatures help prevent the decomposition of the nuts and seeds.

Deciduous forest plants

A deciduous forest typically has three to four, and sometimes five, layers of plant growth. Tall deciduous trees make up the top layer of plant growth, and they create a moderately dense forest canopy. Although the canopy is moderately dense, it does allow sunlight to reach the forest floor. This sunlight allows plants in the other layers to grow. The second layer of plant growth includes saplings and species of trees that are naturally shorter in stature. A third layer (or understory) would include shrubs. Forest herbs, such as wildflowers and berries, make up a fourth layer. During the spring, before the deciduous trees leaf out, these herbs bloom and grow quickly in order to take advantage of the sunlight. A fifth layer would include mosses and lichens that grow on tree trunks.

Plant adaptations

In the spring, deciduous trees begin producing thin, broad, light-weight leaves. This type of leaf structure easily captures the sunlight needed for food production (photosynthesis). The broad leaves are great when temperatures are warm and there is plenty of sunlight. However, when temperatures are cold, the broad leaves expose too much surface area to water loss and tissue damage. To help prevent this damage from occurring, deciduous trees make internal and physical adaptations that are triggered by changes in the climate. Image of deciduous forest trees with leaves of red and orange.

Cooler temperatures and limited sunlight are two climatic conditions that tell the tree to begin adapting. In the Fall, when these conditions occur, the tree cuts off the supply of water to the leaves and seals off the area between the leaf stem and the tree trunk. With limited sunlight and water, the leaf is unable to continue producing chlorophyll, the “green” stuff in the leaves, and as the chlorophyll decreases the leaves change color. The beautiful display of brilliant red, yellow, and gold leaves, associated with deciduous forests in the fall, is a result of this process. Most deciduous trees shed their leaves, once the leaves are brown and dry.

Humans in the ecosystem

The original broad lived deciduous forest that covered most of the lowlands of temperate Europe have almost disappeared to give way to an intensively farmed landscape. (Peterken, G. F., 1996). European natural nemoral woodland is considered to be among the most degraded ecosystems in the world (Jędrzejewska et al., 1994). Although there is the perception that the greatest concern should be held for tropical rain forests, temperate deciduous forests have a smaller fraction of original vegetation remaining than boreal or tropical forests, and also have been more severely impacted by land use change and air pollution.

Remaining deciduous forests in the Fennoscandian boreal landscape have high ecological value, and are considered as key components of the forest landscape.

In Europe and North America, less than 1% of all temperate deciduous forests remain inundisturbed state, free of logging, grazing, and deforestation or other intensive use.

In south and central Sweden, during the 20th century much of the deciduous forests were transferred to coniferous forest plantations, while the remaining deciduous forests are to a large extent also characterized by commercial forestry. Estimates by SEPA indicates that less than 2% of the original distribution of deciduous forests are still intact, in terms of natural forest dynamics.

In Norway more than 20% of the broad-leaved forests are logged and replaced with non-native tree species. The forest sector continues this destructive management, manipulating living forests into boring monoculture of non-native species. This is the biggest threat to this unique and biodiversity rich forest ecosystem, for which Norway has an international responsabiliity.

The history of deciduous forest in Scandinavia: The example of picea albes

Although climate changes are considered as the driving force of forest modification, (Webb 1987), the actual vegetation landscape of Europe is the result of thousands years of interferences between human activity and forests. (Behre, 1988; Huntley & Webb, 1989).

This can be illustrated by the immigration of Picea abies into Fennoscandia. Both human disturbance and climatic change are responsible factors (Tallantire, 1977; Nunez & Vuorela, 1979; Huntley, 1988; Dahl, 1990).

To retrace forest landscape history we can use pollen analysis (Bradshaw, 1988; Bradshaw & Zackrisson, 1990).

The major deciduous tree species in the Fennoscandian boreal forest, Betula pendula, B. pubescens and Populus tremula, all depend on disturbance for their perpetuation (Zackrisson, 1985; Nikolov & Helmisaari, 1992)

Pollen records and charcoal remains provide evidence of intense deforestation for agricultural uses 4000 years ago in Southern Scandinavia.

This clearing facilitated a dramatic change in the forest composition, although at the beginning in southern Sweden forest where dominated by deciduous trees and Spruce were found only in the northern and central part of Sweden,(Bjorse & Bradshaw 1998, Lindbladh & Bradshaw, 1998) During the following two millennia, the spruce spread southwards rapidly and is now the dominant forest species in most of southern Sweden.

This process has been explained as being based on a combination of climatic changes and of anthropogenic influences such as grazing by domestic animals, selective cuttings, pollarding, and burning, which has been unfavorable for deciduous tree species (Nilsson, 1997a, Lindbladh et al., 2000).

Since the mid-19th century the Swedish boreal land- scape has been transformed by forestry operations, which have produced intensively managed forests, mainly even-aged conifer monocultures, in which production of tim- ber and pulpwood are the main goals (Ostlund et al. 1997; Linder & Ostlund, 1998; Axelsson & Ostlund, 2001)

The landscape perspective has come to play an important role in efforts to achieve sustainable forestry, especially regarding the protection of biodiversity

However, many temperate zone economies have shifted from rural, agricultural to urban manufacturing and technologically driven economies. This has led to large-scale agricultural abandonment and the reversion of agricultural lands back to forests. Recent studies indicate an increase in forest area and volumes in both North America and Europe (Kauppi et al., 1992; Houghton, 1995).

Restoration and management of deciduous forests

Temperate deciduous forests are important to regional economies as a source of wood, they provide many ecological services, and they play a major role in the global carbon cycle

The need to repair habitat and restore forest structure and function is recognized throughout the boreal and temperate zone as a component of sustainable forest management. Forest restoration is a complex task, complicated by diverse ecological and social conditions, that challenges our understanding of forest ecosystems.

Forest are human dominated ecosystems. Reconstructing forests where they are now absent, as well as altering existing forests to more natural conditions, are important aspects of sustainable forest management.

Rare herbaceous species, lichens, mosses, insects and birds that are dependent on old, dying and dead deciduous trees occur in these forests

(Sturesson, 1983; Lundqvist, 1986; Wikars & As, 1991)

In Söderåsen National Park Sweden

CONCLUSION:

WHAT FUTURE FOR TEMPERATE FORESTS?

Long, long ago forests of oak, elm, beech, chestnut, maple, ash, poplar, linden, birch, and many other species blanketedmost of the lowlands of Europe. Similar forests covered much of the northeastern United States. Many of those forests have gone, cleared by long-dead settlers to make way for farms.

Farms were needed, of course. People must be fed-and so must the draft animals that helped the farmers till the land. But forests have always been needed. Most furniture, house frames, floors, and everyday tools are made wholly or partly from wood. This book is made from paper manufactured from what were once trees growing in a forest. Wood was once the only fuel that heated every home, from the king’s palace and the baron’s castle to the villager’s cottage. It cooked everyone’s meals, and the only way to obtain hotwater for washing was to place a cauldron over a wood fire.

Many people burn wood to keep warm even today. We mayboast of living in the “Information Age,” but the truth is that we live in the Wooden Age, and we always have.

Nowadays a new use has been found for our forests, basedon a deeper understanding and appreciation of the way they function. Forests are seen not simply as sources of raw materials and fuel, but as living communities of plants, animals, fungi, and organisms so small they can be seen only with the aid of a microscope. The forest reveals itself as a wonderland of diversity, a community of living organisms so vast and complex as to be barely comprehensible.

Most North Americans and Europeans now live in cities. The countryside and its forests are remote from the sidewalks, subways, city blocks, and suburban sprawl, and city parks are pale imitations of genuine countryside. This makes the forests still more special-and valuable. The forest is a place to visit. It is where families can walk, children can play, and naturalists can observe what is around them. It is where scientists can study the planet we all share, and where students can learn.

Throughout much of the Tropics, forests are being cleared, although strenuous efforts are being made to halt the clearances.

In temperate regions, on the other hand, the forests are expanding. Forests that have stood for centuries, known as old-growth forests in most of the world and as ancient woodland in Britain, are protected. The protection is not always effective and valued forests are sometimes lost, often through illegal logging, but conservation bodies are increasingly vigilant and the chainsaws can no longer enter the forest unchallenged.

It seems certain, therefore, that the temperate forests will survive long into the future. Changes in the climate may alter their composition, but forests are not static; their composition is changing all the time. Trees come and go, but the forest will remain. Of that we may be certain.