Landscape scales

Stanley EH, Eisher SG, Jones JB (2004) Effects of water loss on primary production a landscape-scale model. Aquat Sci 66 130-138... 

Nelson E, Mendoza G, Regetz J, Polasky S, Tallis H, Cameron D, Chan KM, et al. Modeling multiple ecosystem services, biodiversity conservation, commodity production and tradeoffs at landscape scales. Frontiers in Ecology and Environment, 2009. 7 pp. 4-11. doi 10.1890/080023... 

Holland, J. and Fahrig, L. 2000. Effect of woody borders on insect density and diversity in crop fields a landscape-scale analysis. Agriculture, Ecosystems, and Environment 78 115. 

Kuck L.R. Balsley B.B. Helmig D. Conway T.J. Tans P.P. Davis K. Jensen M.L. Bognar J.A. Arrieta R.V. Rodriquez R. and Birks J.W. (2000). Measurements of landscape-scale fluxes of carbon dioxide in the Peruvian Amazon by vertical profiling through the atmospheric boundary layer. Journal of Geophysical Research, 105(D17), 22137-22146. 

In a chemically disturbed landscape unit, exposure concentrations, as well as population and community responses, may show clear spatial patterns. Assessing risks at a landscape scale (e.g., watershed), however, requires the development of a... 

Can data from small-scale studies be used to predict effects at the landscape scale ... 

Fahrig L, Freemark K. 1995. Landscape-scale effects of toxic events for ecological risk assessment. In Cairns J, Jr, Niederlehner BR, editors. Ecological toxicity testing scale, complexity, and relevance. Boca Raton (FL) Lewis Publishers, p 193-208. 

Topping CJ. 1997. Predicting the effect of landscape heterogeneity on the distribution of spiders in agroecosystems using a population dynamics driven landscape-scale simulation model. Biol Agric Hort 15 325-336. 

Spatial variations in exposure This could, for instance, be relevant if some species failed to recover in a mesocosms study, whereas in the real world migration would enable recovery. In such situations ecological modeling may be used to extrapolate from mesocosm scale to landscape scale (e.g.,... 

Carlsen TM, Cody JD, and Kercher JR, The spatial extent of contaminants and the landscape scale An analysis of the wildlife, conservation biology, and population modeling literature, Environ. Toxicol. Chem., 23, 798, 2004. 

The transect approach was just one of many solutions to cope with the problem of spatial variability of processes and their integration to larger scales. Figure 1 summarizes a whole suit of approaches that were used to understand and to integrate highly variable processes at the landscape scale (Schulze et al., 1999). 

FIGURE 1 A summary of approaches to integrate highly variable processes of ecosystems at the plot and at the landscape scale in the context of global change (Schulze et nl, 1998). 

Some ecosy.stem processes are carbon neutral on a landscape scale because of disturbance-related variability but show distinct trends (positive and negative) at plot within landscapes. Relatively few types of direct measurements are possible at the landscape. scale and so the differences in plot and landscape behavior will be a major problem in predicting the effects of the implementation of the Kyoto protocol with respect to mitigation of the increase in atmospheric CO,. 

To estimate landscape-scale changes in soil CO, flux, w e multiplied patch/soil-specific estimates of annual soil respiration (McCulley, 1998) by patch area. We then computed changes in patch area with a succession model (Scanlan and Archer, 1991). Landscape-scale soil respiration (kg C ha year ) is projected to have increased from 6687 (200 YBP) to 7377 (1990s) to 7602 (200 years in future)(Table 5). This represents a 10.3% increase with the transition from historic grassland savanna to the present-day savanna parkland-thorn woodland complex, with an additional 3% increase occurring if the present savanna parkland progre.s.ses... 

TABLE 5 Projected Landscape-Scale Changes in Annual Soil Respiration (SR kg C ha year ) Accompanying Succession from an Open Savanna/Grassland to Woodland and Potential Changes in Mean Annual Temperature... 

Vourlitis, G. L., and Oechel, W. C. (1997). Landscape-scale CO , H 0 and energy flux of moist-wet coastal tundra ecosystems over two growing seasons./. Ecol. 85, 575-590. 

Devito, K.J., Hill, A.R. and Dillon, P.J. (1999). Episodic sulphate export from wetlands in acidified headwater catchments Prediction at the landscape scale. Bio-geochem., 44, 187-203. 

Timothy H. Tear is the Director of Conservation Science for The Nature Conservancy s Eastern New York Chapter. He is responsible for chapter-wide conservation science and planning leadership and providing support to landscape-scale conservation projects. He received his B.S. from the University of New Hampshire and his M.S. and Ph.D. from the University of Idaho. 

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