Patchy environments

Wiens, J.A. 1976. Population responses to patchy environments. Anna. Rev. Ecol. Syst. 7, 81-120. 

Campos, D., Mendez, V, Ortega-Cejas, V Lattice models for invasions through patchy environments. Bull. Math. Biol. 70(7), 1937-1956 (2008). http //dx.doi.org/10.1007/ S11538-008-9333-2... 

Burkey, T. V. Stenseth, N.C. 1994. Population dynamics of territorial species in seasonal and patchy environments. Oikos 69 47—53. 

Stanton, M. L. (1982a) Searching in a patchy environment Food plant selection by Colias p. eriphyle butterflies. Ecology, 63, 839-53. 

R. B. Jackson and M. M. Caldwell, Integrating resource heterogeneity and plant plasticity modelling nitrate and phosphate uptake in a patchy soil environment. J. Ecol. 84 891 (1996). 

Fig. 6.1 Different plant strategies for dealing with patchy distribution of P in soil (a) initial situation random distribution of roots, (b) increased root production, (c) production of cluster roots in high-P environments, (d) production of cluster roots at random. For discussion, see text...

The products cannot be compared with regard to the environment and health-related risks, so great the level of uncertainty and the fear of making a wrong decision are. This situation encourages a conservative stance in investment and procurement decisions of chemicals users. Patchy information for new products are thus frequently overstressed (in mai r instances also for tactical reasons). This conservative stance is favoured even more by the fact that most users know of cases where the substitutes proved to be just as problematic or even more problematic after a few years. 

Strickland JDH, Parsons TR (1972) A practical handbook of seawater analysis. Bull Fish Res Bd Canada 167 1-311 Suzuki R, Ishimaru T (1990) An improved method for the determination of phytoplankton chlorophyll using N, N-Dimethylformamide. J Oceanogr Soc Japan 46 190-194 Tiselius P (1992) Behavior of Acartia tonsa in patchy food environments. Limnol Oceanogr 8 1640-1651 Thingstad TF, Billen G (1994) Microbial degradation of Phaeocystis material in the water column. J Mar Syst 5 55-65... 

Intertidal areas are difficult to study from a practical point of view and offer conceptual challenges to developing the quantitative budgets required to address questions about nutrient transport between land and sea. The methods employed must take account of the key attributes of the intertidal environment which include variability, patchiness scales and... 

The nature of the soil environment can also affect metal speciation and microbial distribution and therefore both individual and community responses. Recent research has demonstrated that bacterial conmiunities are not distributed randomly in soil, and spatial patterns have been identified in the distribution of bacteria and bacterial function at scales from several millimeters to several meters (Foster, 1988 Robertson et al., 1997 Nunan et al., 2002, 2003). Evidence for bacterial patchiness at scales below 1 mm is now available (Grundmann et al., 2001 Nunan et al., 2002, 2003). It has been suggested that microscale spatial patterns may have a regulatory effect on bacterial activity as a result of the diffusional limitations imposed on nutrient uptake and on metabolite excretion and dispersion. These may have rate-limiting or stimulatory effects on several microbially mediated processes (Darrah et al., 1987 Grundmaiui et al., 2001). 

Downing, J.A. and L.C. Rath. 1988. Spatial patchiness in the lacustrine environment. Limnol. Oceanogr. 33 447-458. 

Although there was no detectable patchiness of the radiocesium distribution in soil within the area, the geostatistical evaluation of the plant data clearly revealed a spatial dependency with a range of about 20 m, which was nearly the same as for the potassium concentration (25 m). This supported the general conclusions that in undisturbed environments with a spatial and vertical irregular distribution of radiocesium in soil, the physiological and ecological properties of special plant communities or individual plants are responsible for the uptake of radiocesium in plants and, if such... 

Now we analyze the trends in Fig. 5 in two steps (1) the silanization procedure in toluene solution and (2) contact angle measurement in an aqueous environment and their surface energies. In the n = I case, silane molecules can bind to reactive sites on the surfaces in a densely packed state but probably patchy style, due to the three bulky methyl groups per silane molecule. 

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