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Biomedical subjects

J P Grime

Publications and source records attributed to J P Grime.

4 recordsLinked to original sources
PubMed2001

Biodiversity and ecosystem functioning: current knowledge and future challenges.

The ecological consequences of biodiversity loss have aroused considerable interest and controversy during the past decade. Major advances have been made in describing the relationship between species diversity and ecosystem processes, in identifying functionally important species, and in revealing underlying mechanisms. There is, however, uncertainty as to how results obtained in recent experiments scale up to landscape and regional levels and generalize across ecosystem types and processes. Larger numbers of species are probably needed to reduce temporal variability in ecosystem processes in changing environments. A major future challenge is to determine how biodiversity dynamics, ecosystem processes, and abiotic factors interact.

Animals↗
PubMed2000

The response of two contrasting limestone grasslands to simulated climate change.

Two different UK limestone grasslands were exposed to simulated climate change with the use of nonintrusive techniques to manipulate local climate over 5 years. Resistance to climate change, defined as the ability of a community to maintain its composition and biomass in response to environmental stress, could be explained by reference to the functional composition and successional status of the grasslands. The more fertile, early-successional grassland was much more responsive to climate change. Resistance could not be explained by the particular climates experienced by the two grasslands. Productive, disturbed landscapes created by modern human activity may prove more vulnerable to climate change than older, traditional landscapes.

Biomass↗
PubMed1986

The ecological significance of plasticity.

Plastic responses of plants to environmental factors may be placed in an ecological context by regarding them as components of sets of traits which are predictably related to habitat stability and productivity. In ephemeral plants of temporary habitats plasticity is a major component of the mechanisms which tend to sustain reproduction when these plants are exposed to stress. When perennials of more stable habitats are subjected to stress the most frequently observed effect of plastic changes in allocation is to defer reproduction, a mechanism which appears to safeguard survival of the parent plant. It is suggested that plasticity is of vital importance in resource acquisition by plants. This hypothesis is supported by the results of experiments in which the roots and shoots of plants of contrasted ecology have been subjected to controlled patchiness in resource supply. We conclude that in plants of productive habitats high morphological plasticity is part of the foraging mechanisms which project new leaves and roots into the resource-rich zones of the constantly changing environmental mosaic created by the activity of competing plants. In long-lived plants of chronically unproductive habitats plasticity is expressed primarily through reversible physiological changes. These appear to maintain the viability and functional efficiency of leaves and roots over their long life spans and facilitate exploitation of the pulses of temporary and unpredictable resource supply which are characteristic of unproductive habitats.

Ecology↗