Direct Seeding Literature Review

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Introduction:
The world’s total forest area is just over 4 billion hectares, which corresponds to an average of 0.6 ha per capita (Figure 1). The five most forest-rich countries (the Russian Federation, Brazil, Canada, the United States of America and China) account for more than half of the total forest area.

Deforestation – mainly the conversion of tropical forest to agricultural land – shows signs of decreasing in several countries. Around 13 million hectares of forest were converted to other uses or lost through natural causes each year in the last decade. At a regional level, South America suffered the largest net loss of forests between 2000 and 2010 – about 4.0 million hectares per year – followed by Africa, which lost3.4 million hectares annually (Figure 5). Oceania also reported a net loss of forest (about 700 000 ha per year over the period 2000–2010), mainly due to large losses of forests in Australia, where severe drought and forest fires have exacerbated the loss of forest since 2000. Asia, which had a net loss of forest of some 600 000 ha annually in the 1990s.

Need of Forest Restoration: Within the last ten years, tropical rainforests have been destroyed at an annual rate of 0.8% of area (Whitemore, 1997). So this things brings to human being to think about the forest restoration. Forest restoration is defined as “actions to re-instate ecological processes, which accelerate recovery of forest structure, ecological functioning and biodiversity levels towards those typical of climax forest” Various forest restoration methods have been developed, for instance, the accelerated natural regeneration ( ANR) (Jansen and Pfeifer , 1989), The Framework Species method(Goosem & Tucker, 1995) and The Maximum Species Diversity method. The ANR method is Effective where natural regeneration is already underway. Eliminates nursery and tree planting costs. Relatively cheap – Capitalizes on “free” ecological services US$ 1,400/ha. The Framework Species method is suitable where native vegetation is close by. Its only need a single planting and it is self sustaining. In the Maximum Species Diversity method a large percentage of species are from the mature phase and primary promoters are avoided. The major disadvantage of this method slower growth rate and post planting management is required. Now a days there is some evidence that , reforestation plays a key role in the long term of restoration of landscape functioning, as well as social and economic development. Reforestation can catalyses and induce succession of forest ecosystems using native species (Parrotta, 2000). Direct Seeding:

An ancient method of establishing trees is by sowing seeds directly where the future trees are required. In many circumstances, this method is superior to the traditional method of planting nursery-raised plants. In several tropical countries, the demand for reforestation is often not met due to limited resources. Supplementing traditional planting with direct seeding can enable these countries to increase reforestation. Direct seeding is a regeneration method of sowing seeds directly where the future trees are required, whether it is for forest plantations, shelterbelts or in agroforestry. In this way the laborious task of raising nursery plants and transplanting them to the planting site is omitted. Direct seeding offers various interesting possibilities e.g. the ability to rapidly increase the area being forested or the ability to provide rural people with an inexpensive method to obtain benefits from trees. History of Direct Seeding:

Direct seeding has over the last 50 years gained in importance, especially in North America and China where large areas have been direct seeded from helicopters or aero planes. Direct seeding from the air has been widely used in China where more than 15 million ha have been reforested between 1956 and 1985 (Xinhua & Jingchun, 1988). In the developed countries more than 1⁄2 million ha were...
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