Quaternary landscape ecology: Relevant scales in space and time

Abstract

Two primary goals of landscape ecologists are to (1) evaluate changes in ecological pattern and process on natural landscapes through time and (2) determine the ecological consequences of transforming natural landscapes to cultural ones. Paleoecological techniques can be used to reconstruct past landscapes and their changes through time; use of paleoecological methods of investigation in combination with geomorphic and paleoethnobiological data, historical records, and shorter-term ecological data sets makes it possible to integrate long-term ecological pattern and process on a nested series of temporal and spatial scales. 'Natural experiments' of the past can be used to test alternative hypotheses about the relative influences of environmental change, biological interactions, and human activities in structuring biotic communities within landscape mosaics.On the absolute time scale of the Quaternary Period, spanning the past 1.8 million years, current distributional ranges of the biota have taken shape and modern biotic communities have assembled. Quaternary environmental changes have influenced the development of natural landscapes over time scales o,f centuries to hundreds of thousands of years; human cultural evolution has resulted in the transformation of much of the biosphere from natural to cultural landscapes over the past 5,000 years. The Quaternary extends to and includes the present and the immediate future. Knowledge of landscape changes on a Quaternary time scale is essential to landscape ecologists who wish to have a context for predicting future trends on local, regional, and global scales.

Fuzzy logika az agrár- és környezetkutatásokban

“…A talajtani kutatásban való lehetséges fuzzy modellek alkalmazásáról RAJKAI (2001) Modellezés és modellhasználat című átfogó tanulmányában tesz említést. DELCOURT & DELCOURT (1988), HOOSBEEK és BRYANT (1992) nyomán a modelleket szerveződési szintjük alapján, hierarchikus rendszerű összefoglalásban mutatja be. A közölt táblázat szerint a fuzzy clustering mérési és becslési eljárás hidrológiai és tömegegyensúly modellek esetében talajrégió léptékben alkalmazható.…”

A Habitat-Based Framework for Communicating Natural Resource Condition

“…Environmental processes typically show a direct relationship between temporal and spatial scales, with fine-scale spatial processes happening rapidly and broad-scale processes happening slowly [16,17]. Many stressors also follow this pattern, with local impacts such as point-source inputs being short term and concentrated in small areas while global impacts such as climate change occur slowly over large spatial scales [18] (Figure 1).…”

“…In some cases, the aggregation of multiple small-scale stressors can also produce larger-scale impacts (Figure 1). Time versus space plots (Stommel diagrams) have been used extensively [17,20] to illustrate these scaling relationships for different organisms and processes in oceanic [21] and terrestrial [16] environments.…”

Modeling forest landscapes in a changing climate: theory and application

“…An equally wide range of models has been developed at each hierarchical level to model these phenomena (Wu et al 2006). At a given level of hierarchy, a modeling system is composed of interacting components (i.e., lower-level entities) and is itself a component of a larger system (i.e., higher level controls) that influences behavior (Delcourt and Delcourt 1988;Wu and Loucks 1995;Wu 1999;Wu and David 2002;Lischke et al 2007). Forest landscape models (FLMs) simulate forest landscape processes (FLPs) at landscape scales and stand dynamics as a function of lower-level entities operating at site-scales, while incorporating regional environments (e.g., climate) as higher level controls (Fig.…”