Vegetation stress

Crawford, M.F., 1986. Preliminary evaluation of remote-sensing data for detection of vegetation stress related to hydrocarbon microseepage Mist gas field, Oregon. Proc. Fifth Thematic Conference on Remote Sensing for Exploration Geology, Reno, pp. 161-177. 

All the formulas described above are for unstressed vegetation, which is the default vegetation status. Optionally, for vegetation stress due to lack of water, the stomatal resistance is increased by a factor of 10 and for inactive vegetation (winter deciduous), a stomatal resistance of 10,000sm 1 should be used, indicating a complete shutdown of this pathway. 

Leshem, Y.Y. and Haramaty, E. (1996) The characterization and contrasting effects of the nitric oxide free radical in vegetative stress and senescence of Pisum sativum Linn, foliage, J. Plant Physiol. 148, 258-263. 

Dohring, T, Kofferlein, M., Thiel, S., and SeidUtz, H.K., Spectral shaping of artificial UV-B irradiation for vegetation stress research, J. Plant Physiol 148, 115, 1996. 

Consider presence of organic material on site, the depth to water table, soil hydraulic conductivity, vegetative stress, odors, etc. 

Evidence of stress on aquatic species or vegetative stress on trees, crops, or plant life located on properties neighboring the site... 

Review records for evidence of vegetative stress or impairment of any nearby sensitive environments. A sensitive environment is defined as a sensitive aquatic environment, nature preserve, habitat for endangered species, sensitive forest reserves, national parks or forests, etc. An adverse effect is considered to be any one or more of the following (i) impairment of the quality of the natural environment for any use that can be made of it, (ii) injury or damage to property or to plant or animal life, (iii) harm or material disconofort to any person, (iv) impairment of the safety of any person, fv) rendering any property or plant or animal life unfit for use by humans, (vi) loss of enjoyment of normal use of property, and (vii) interference with the normal conduct of business (from Ontario Environmental Protection Act, 1980). 

Gutting Mills. The machines applying stress by cutting are described in Figure 3e. They are usually employed for size reduction of ductile materials such as plastics, vegetables, and animal products. 

Visual evidence of stained soils, stained pavement or stressed vegetation... 

Previously no stress or applied stress lasting 16 hours with sample coated with vegetable oil prior to testing for the short-term stress-strain behavior shown. 

A positive feedback between vegetation and atmospheric CO2 will occur if biomass declines. This will happen to the extent that climatic warming causes increased water stress, either through decreased precipitation or increased evap-otransporation, particularly on soils of low water-holding capacity. Decreases in soil nutrient availability, either directly caused by drought or indirectly caused by replacement with taxa with more recalcitrant litter, may further decrease the net release of carbon from the biosphere to the atmosphere. Positive feedback will also arise if the current standing biomass of trees is replaced by small trees, shrubs, and herbs that store less carbon. 

Fig. 1. (a) Model describing the various equilibria between competition, stress and disturbance in vegetation and the location of primary and secondary strategies. C, competitor S, stress tolerator R, ruderal C-R, competitive-ruderal S-R, stress-tolerant ruderal C-S, stress-tolerant... 

In addition to the mechanisms of stress response so far considered, there are several others which have attracted the attention of plant ecologists. These include innate or environmentally determined forms of dormancy in seeds, spores, and vegetative buds, many of which represent adaptive responses restricting plant growth and development to favourable seasons or sites. Dormancy has been the subject of numerous publications and will not be considered here. Instead, opportunity will be taken to refer to two forms of plant response to stress which until recently have received only scarce attention. The first is the phenomenon of stored growth whilst the second involves the response of the developing shoot to mechanical impedance. 

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