Deciduous forests

Carbon. Most of the Earth s supply of carbon is stored in carbonate rocks in the Hthosphere. Normally the circulation rate for Hthospheric carbon is slow compared with that of carbon between the atmosphere and biosphere. The carbon cycle has received much attention in recent years as a result of research into the possible relation between increased atmospheric carbon dioxide concentration, most of which is produced by combustion of fossil fuel, and the "greenhouse effect," or global warming. Extensive research has been done on the rate at which carbon dioxide might be converted to cellulose and other photosyntheticaHy produced organic compounds by various forms of natural and cultivated plants. Estimates also have been made of the rate at which carbon dioxide is released to soil under optimum conditions by various kinds of plant cover, such as temperature-zone deciduous forests, cultivated farm crops, prairie grassland, and desert vegetation. 

Several studies, based on models, examined the effects of land-use change on the global carbon cycle and conclude that there is a net release of carbon due to land clearing. However, the results and conclusions of these studies are based on assumed sizes of vegetation carbon pools which are inputs to the models. For example, Melillo et al. 24) concluded that boreal and temperate deciduous forests of the northern hemisphere are net sources of atmospheric carbon. Their analysis used values for carbon density derived by Whittaker and Likens 19) from work by Rodin and Bazilevich (27). Rodin and Bazilevich extrapolated results of small, unrelated studies in Europe and the USSR to estimate total biomass of Eurasian boreal and temperate deciduous forests. Their estimates have since been extrapolated to forests worldwide and are used often today. 

Temperate Deciduous Forest Global Average Primary 174 89... 

Much of the surface soil erosion and hence nutrient loss occurs when deforestation and biomass burning removes and/or consumes the organic materials that protect the soil surface. Significant losses may occur by dry ravel or overland water erosion associated with precipitation events. Under a shifting cultivation system in a tropical deciduous forest ecosystem in Mexico, Maass et al. 61) reported first year losses of N, P, K, and Ca were 187, 27, 31, and 378 kg ha" respectively. In contrast, losses in adjacent undisturbed forests were less than 0.1 kg ha for all nutrients except Ca (losses were 0.1-0.5 kg ha for Ca). 

Alfisols Bt horizon with moderate base saturation Temperate deciduous forests... 

Aggradation or degradation of biomass or soil reservoirs may also produce effects that appear to be fractionation. This is because the elemental ratios in vegetation or soil reservoirs can be very different from those of bedrock. Sufficiently large and rapid changes in these reservoirs are sometimes evident in river chemistry. For example, the uptake and release of potassium in association with the seasonal growth and loss of leaves can affect the composition of streams that drain temperate deciduous forests (Likens et al, 1977 Vitousek, 1977). 

Goulden, M. L., Munger, J. W., Pan, S.-M., Daube, B. C. and Wofsy, S. C. (1996). Exchange of carbon dioxide by a deciduous forest Response to inter-armual climate variability. Science 271,1576-1578. 

Fig. 10. The effects of chestnut blight (Endothia parasitica) on a deciduous forest ecosystem (after Day Monk, 1974).

The fate of areas of south-eastern American deciduous forests which were dominated, before the arrival of the pathogen, by chestnut and species of oak has been traced (Fig. 10) over nearly 40 years (Day Monk, 1974). The demise of chestnut from its standing as a canopy dominant was rapid, taking about 20 years, with a complete failure to return. During this period eeosystem productivity was reduced (as shown by a reduction in tree basal area. Fig. 10). However, the place of chestnut in the forest has been taken by a number of species, in particular oak and tulip tree, which have steadily increased in dominance. The community has clearly changed markedly but the ecosystem as a whole has shown complete recovery, in terms of re-establishing tree basal area. The place of chestnut in the oak-chestnut forests has been taken by other native species. So in the context of conservation, although the loss of chestnut is unfortunate, it has not been at the eost of an invasion of alien species of tree. 

Taylor, R.J. Pearcy, R.W. (1976). Seasonal patterns in the CO2 exchange characteristics of understorey plants from a deciduous forest. Canadian Journal of Botany, 54, 1094-1103. 

Meyers TP, Huebert BJ, Hicks BB. 1989. HNO, deposition to a deciduous forest. Boundary-Layer Meteorol 49 395 10. 

Rea AW, Lindberg SE, Keeler GJ. 2001. Dry deposition and foliar leaching of mercury and selected trace elements in deciduous forest throughfall. Atmos Environ 35 1352-2310. 

The area is 7,808 hectares and the altitude ranges from 250 to 762 m. The soil is categorized as an Orthic Acrisol according to the FAO/UNESCO scheme (FAO/UNESCO 1979). The vegetation includes dry evergreen forest (DEF), dry deciduous forest (DDF) and plantation plots as the major vegetative types (Fig. 1). The climate is classified as Aw (Koppen 1931). The annual precipitation is 1,260 mm and the average temperature is 26°C. 

Fig. 1. The vegetative types of the Sakaerat Environmental Research Station (SERS) and the sampling points. DDF and DEF indicate dry deciduous forest and dry evergreen forest, respectively.

Fig. 2. Antibiotic resistance MPN profiles of the soils. The solid, open and gray bars indicate BG, DDF and DEF, respectively. The upper figure (a) shows the row MPNs and the lower figure (b) shows the ratio-transformed values. The error bar indicates the standard deviation (n=6, bare ground n=7, dry deciduous forest or dry evergreen forest). For each antibiotic, the bars indexed with the same letter do not differ significantly at p=0.05, according to the Dunnett T3 t-test.

Sakurai K, Tanaka S, Ishizuka S, Kanzaki M (1998) Differences in soil properties of dry evergreen and dry deciduous forests in the Sakaerat Environmental Research Station. Tropics 8 61-80... 

Among the natural areas in the Ebro River basin, a broad spectrum of landscapes is scattered, ranging from boreal-alpine coniferous forests, mixed deciduous forests, Mediterranean evergreen and mixed forest and shrubs, and semi-arid treeless formations. 

Kristensen HL, Gundersen P, Callesen I, Reinds GJ (2004) Throughfall nitrogen deposition has different impacts on soil solution nitrate concentration in European coniferous and deciduous forests. Ecosystems 7 180-192... 

The receptors of interest are soils of agricultural (arable lands, grasslands) and non-agricultural (forests, steppes, heath lands, savanna, etc.) ecosystems. In non-agricultural ecosystems, the atmospheric deposition is the only input of heavy metals. Regarding the Forest ecosystems, a distinction should at least be made between Coniferous and Deciduous Forest ecosystems. When detailed information on the areal distribution of various tree species (e.g., pine, fir, spruce, oak, beech and birch) is available, this should be used since tree species influence the deposition and uptake of heavy metals and the precipitation excess. On a world scale, soil types can be best distinguished on the basis of the FAO-UNESCO Soil Map of the World, climate and ecosystem data from NASA database (1989). 

Hawkins, C. E. (1998) Behaviour and ecology of the fossa, Crytoprocta ferox (Carnivora Viver-ridae) in a dry deciduous forest, western Madagascar. Unpublished PhD thesis, University of Aberdeen, Schottland. 

Elkinton, J. S., Card6, R. T., and Mason, C. J. (1984). Evaluation of time-average dispersion models for estimating pheromone concentrations in a deciduous forest. Journal of Chemical Ecology 10,1081-1108. 

It was concluded in Chapter 5.2 that the contrasting needs of detail and conciseness in describing the local-geographic distribution of natinal products can be best met by subdividing land into biomes. Traditionally, these comprise the tropical rain forest, grassland and savanna, scrub and deciduous forest, tenq)erate grassland, deciduous forest, chaparral, and taiga and tundra (Fig. 6.1). 

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