Academic literature on the topic 'Rain forests, juvenile literature'

Abstract Forest fires can be one of the greatest causes of loss in forests since, at their most severe, they can wipe out entire stands by spreading through the forest canopy. Certain years come to be recognized as ‘forest fire years ‘ when persistently hot, dry weather brings an exceptionally high risk of damage. Information on fire risk factors and on prevention and control can be found in the specialist literature. Storm damage can take the form of ‘windthrow, ‘ when the whole tree is uprooted or of ‘wind snap, ‘ when the root anchorage is relatively firm, but the stem breaks under wind pressure which exceeds its bending strength. Windthrow, which progresses through a stand due to restricted rooting, is said to be ‘endemic, ‘ while extensive windthrow due to severe storms, regardless of site conditions is described as ‘catastrophic ‘. Storm damage destabilizes the forest ecosystem, sometimes favoring the build up of pests, especially bark beetles that can harm surviving trees or logs awaiting extraction in coniferous stands (227). Breakage due to ice or snow can occur when excessive accumulations build up in extreme winter weather. In the case of ice, accumulation occurs when supercooled rain freezes on contact with the tree. The weight of ice or snow can break leading shoots as well as branches. Pines, spruces, Silver fir, Cedar of Lebanon, and beech are particularly at risk.

Mycorrhizae and plants have a well-established symbiotic relationship, and play an important role in better plant growth, disease protection, and improving soil quality. Arbuscular and ectomycorrhizae are the most common of the seven species of mycorrhizae described in the scientific literature (arbuscular, ecto-, ectendo-, arbutoid-, monotropoid-, ericoid-, and orchidaceous mycorrhizae). This chapter presents a summary of current knowledge of mycorrhizal interactions, processes, and potential benefits to society. The molecular basis for genetic exchange between arbuscular mycorrhizal (AM) fungi and host crops, the role of AM fungi in disease protection, in promoting plant growth, in reducing heavy metal load, and in increasing grain production, and their impact on sustainable agriculture are presented in this chapter. The impact of AM-fungal incorporation and beneficial saprophytic mycoflora on the promotion of plant growth and root colonization, the role of AM fungus in restoring indigenous ecosystems, and the impact of the mycorrhizosphere on multitrophic interactions have been summarized. The ways in which the mycorrhizae transform the disturbed ecosystem into productive land are discussed. The importance of restoring mycorrhizal systems in the rhizosphere is emphasized, and their impact on land reclamation and environmental remediation of polluted soils is also discussed. The importance of ectomycorrhiza in forest ecosystems, ectomycorrhizal association in tropical rain forests and their role in maintaining thermal monodominance, are briefly explained.

Although the global social benefits of establishing protected areas in tropical rain forests may outweigh the total costs, the local private costs of restricting access to an important resource may be relatively substantial for residents and communities. The imbalance between costs accruing at the local level and benefits accruing at the national and international levels has raised questions about whether people living in or near protected areas ought to be compensated for their losses, and if so, how compensation should be made. The issue of compensating residents for lost resources has been discussed, implicitly or explicitly, in many treatments of the relationship between protected areas and local people, as well as in treatments of externalities. (Economists define externalities as actions of consumers or producers that affect the well-being of others in a way that is not reflected through prices or economic transactions.) In the literature on compensation, there is a large difference of opinion on whether compensation should be paid to victims of negative externalities, which include such things as the pollution of air or water and the siting of hazardous waste dumps. A number of studies have argued for compensation of those people subject to negative externalities, at least in particular situations or through particular mechanisms Oohnson, 1977; O'Hare, 1977; Western, 1982; Knetsch, 1983; Ward, 1986; Tietenberg, 1988; Hodge, 1989; Sullivan, 1990, 1992; Barnett, 1991; Burrows, 1991; McNeely, 1991; Miceli, 1991; Farber, 1992; Pollot, 1993). Other authors, mainly economists, have argued equally persuasively against compensation in many or all situations (Knetsch, 1983; Blume et al., 1984; Baumol and Gates, 1988). Most of the differences of opinion derive from differences in the context of the case examined, the assumptions made, the criteria used for judging the desirability of outcomes, interpretations of relevant laws, and the proposed mechanism for compensation. In the context of protected areas, most authors have argued in favor of compensating residents (e.g., Western, 1982; Barnett, 1991; McNeely, 1991). A unique best choice regarding compensation is not indicated in economic and political theory. Few protected area projects have attempted large-scale compensation initiatives; thus, there are few field examples to guide the discussion.

Environmental flows of extreme importance, such as turbulent atmospheric boundary layer over thick rain forests, may benefit from more realistic mathematical models. Accordingly, flow over layers of dense vegetation can be characterized by some sort of porous structure through which a fluid permeates. For hybrid media, involving both a porous structure and a clear flow region, difficulties arise due to the proper mathematical treatment given at the interface. The literature proposes a jump condition in which shear stresses on both sides of the interface are not of the same value. This paper pr