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Plants 



Overview 



This section describes 

 trends in two of the major 

 kingdoms of hfe on earth: the green plants of 

 the Kingdom Plantae and the molds, hchens. 

 and mushrooms of the Kingdom Fungi. 

 Members of the plant and fungal kingdoms have 

 both economic and ecological importance. Plants 

 transform solar energy into usable economic 

 products essential in our modem society and 

 provide the basis for most life on earth by gen- 

 erating oxygen as a product of photosynthesis. 

 Fungi not only mediate critical biological and 

 ecological processes including the breakdown 

 of organic matter and recycling of nutrients, but 

 they also play important roles in mutualistic 

 associations with plants and animals. Members 

 of the Kingdom Fungi also produce commer- 

 cially valuable substances including antibiotics 

 and ethanol, while other fungi are pathogenic 

 and cause damage to crops and forest trees. 

 Because fungi and plants play such fundamen- 

 tal roles in our lives, it is important to have a 

 comprehensive knowledge of the taxa com- 

 prising these groups. However, at a time 

 when we are increasingly recognizing the 

 importance of these groups, we are impoverish- 

 ing our biological heritage. Rates of species loss 

 are reaching alarming levels as ecosystems are 

 degraded and habitat is lost. This erosion of bio- 



logical diversity threatens the maintenance of 

 long-term sustainable development and protec- 

 tion of the earth's biosphere. 



Questions involving biological diversity are 

 now of major concern to scientists, the general 

 public, and government agencies with mandates 

 for natural resource protection. Much of this 

 concern has been directed toward tropical forest 

 systems because of their high levels of biodi- 

 versity, although other regions, including the 

 United States, deserve our immediate attention. 

 Certainly, a first step toward conserving biolog- 

 ical diversity must be based on a firm knowl- 

 edge of the numbers and distribution of existing 

 species. Developing good estimates of species 

 diversity is also important in describing histori- 

 cal and cunent trends of species dynamics. 

 Unfortunately, despite the existence of various 

 state and regional surveys, the efforts of taxon- 

 omists and natural historians, and the publica- 

 tion of various floras, we still do not have pre- 

 cise estimates of the status of plant and fungal 

 taxa in the United States. Estimates for vascular 

 plant taxa in the United States range upward 

 from 17,000 species (Morin, Morse et al., this 

 section). In contrast to this well-studied group, 

 only 5%-10% of an estimated 1 .5 million fungal 

 species have been described worldwide 

 (Rossman, this section). 



by 

 Science Editor 



Glenn R. 



Guntenspergen 



National Biological 



Service 



Southern Science Center 



700 Cajundome Boulevard 



Lafayette, LA 70506 



