Natural forest

Wind-throw and wind-snap of forest trees is a normal process in natural forests (Spurr Barnes, 1980). Runkle (1982) has estimated that, annually, as much as 1% of the area of a forested ecosystem may be blown (or fall) over and create canopy gaps. Such a figure appears to be appropriate for a range of forested ecosystems from equatorial to boreal. The canopy gaps are critical for the establishment of new species and maintaining species diversity in the forest (Woodward, 1987). 

Whereas gap creation by wind maintains diversity in natural forest... 

SL 1.1 662 NE42.50 30° Coniferous broad-leaved mixed forest (natural forest), consists mainly of Engelhardtia chrysolepis Hance, Bridelia monoica (Lour.) Merr., and Machilus velutina Champ. July 1998... 

Critical Loads of Heavy Metals Depending on ERA Endpoints The ecosystem characteristics of case study plots in various natural forests of the European part of Russia are shown in Table 4. Critical loads in an occasion of human health and ecotoxicological effects on biota (endpoints) have been accounted. Corresponding critical limits of HM concentration in soil drainage waters are presented in Table 1. 

Natural forest Plantation forest (million ha) (million ha)... 

When abscisic acid is applied to balsam fir, the break of buds in the spring is delayed and the emerging spruce budworm, Choristoneura fumiferana, larvae are forced to feed on old needles, which are a less desirable food. Attempts have been made, rather unsuccessfully, under natural forest situations, to manipulate budbreak with growth retardants for the control of the spruce budworm. However, this system seems to operate under controlled greenhouse conditions, and with some adjustments, it may have potential for practical applications in the field (32). 

Boisvenue, C., and Running, S. W. (2006). Impacts of climate change on natural forest productivity—Evidence since the middle of the 20th century. Global Change Biology 12(5), 862-882. 

Bjorkman, L., and Bradshaw, R. H. W. (1996).The immigration of Fagus sylvatica L. and Picea abies (L.) Karst into a natural forest stand in southern Sweden during the last 2000 years. J. Biogeograph. 23, 235-244. 

Of course, an accurate assessment of the fluxes of chemical elements in the atmosphere-vegetation-soil system is only possible with a detailed inventory of land covers. For instance, Fang et al. (2001) have undertaken such an inventory for seven time periods over the territory of China, including both planted and natural forests. It was shown that a maximum rate (0.035 PgCyr-1) of carbon assimilation from the atmosphere was observed between 1989 and 1993. Under this, different types of forest had various time periods for a maximum rate of carbon assimilation. This confirms... 

Lopes de Carvalho, L. M. and Linhares, A. X. (2001). Seasonality of insect succession and pig carcass decomposition in a natural forest area in southeastern Brazil. /. Forensic Sci. 46, 604-608. 

Sharma, R., Sharma, C. and Sharma, E. (2002) Energy efficiency of large cardamom grown under Himalayan alder and natural forest. Agroforestry Systems 56(3), 233-239. 

Timonen, S. Sen, R. (1998). Heterogeneity of fungal and plant enzyme expression in intact Scots ymt-Suillus bovinus and -Paxillus involutus mycorrhizospheres developed in natural forest humus. New Phytologist, 138, 355-66. 

Cerri, C. C., B. Volkoff, and F. Andreux. 1991. "Nature and behavior of organic matter in soils under natural forest, and after deforestation, burning and cultivation, near Manaus." Forest Ecology and Management 38 247-257. 

In the past, reforestation relied on the establishment of monospecific plantations, often with exotics (e.g.. Eucalyptus, Pinus, Acacia spp.) or a limited number of native tree taxa for which seeds are readily available and silvicultural practices have been developed (Knowles and Parrotta 1995). Also at Porto Trombetas, about 160 native forest species in mixed plantings were evaluated for their suitability for forest restoration on bauxite mine land over a 14-year period. Observations over 600 ha of plantings have yielded information on ecological characteristics of the species and cost-effective propagation methods. The plantations of exotics and natives are expected to catalyze natural forest succession in the understory and thus accelerate the rate at which species-rich native forest stands develop on severely degraded lands. 

Element Natural forest aerosol 60 km north of Manaus Typical aerosol from forest burning area, valley of Rio Madeira... 

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