Overview:

This project seeks to develop to a prototype of a substance that has a uniform weight, composition, and shape that can be placed in an environment. After a specified period it will be partially consumed or used by the biota of an area and degraded by other chemical and physical pathways. The changing weight of the substance over time will reflect changes in gross ecological activity. The changes are held to be the sum of the many unspecified processes. The substance is an "integrator," a synthesizer of many of the factors of an environment as well as their associated dynamics. The change in weight of the substance will be taken to be an index to ecological activity of a relatively large community or ecosystem. The more rapid the mass loss, generally, the more biologically rich and/or active the community. Average values from many such placements can reflect the dynamics of a large area and can become a standard for correlating and standardizing observations among areas and periods. Reduction in weight loss over a standardized period for an area may suggest influences of pollutants or other undesirable influences.

There is a need for a low cost, readily-standardized substance, an "ecological agar" that, when cast as standard-weight rods, pellets, or wafers, could be placed in a contaminated area and rates of change in the mass of the item determined. The project proposed has the major advantage (from one perspective) of avoiding the costs, time, and taxonomic difficulties of more conventional methods. Reducing the costs and increasing the number of samples taken for managing very large areas (e.g., wildlife refuges, national parks) is likely to provide managers now-unavailable information, at least warnings or "red flags" for decisions.

The selected substance and objects made from it that can be used specifically to estimate the change in degradation of litter in forests and ponds. It will likely be used in other places and ways but concentration herein is on forest leaf litter and pond waters. Degradation means the sum of the several forces working on the dead-material community of the forest floor and it includes the action of the micro-biota as well as photochemical and mechanical breakdown and leaching. Our working hypothesis is that generally temperature, moisture, and solar radiation are the dominant natural factors influencing biota and other operatives in the complex degradation process. Fertilizers, pollutants, and other human-added chemicals can speed or slow the process. Degradation is complex and the objective is not to describe the details of that system of processes but to develop a general index to the cumulative effects within a large community (e.g., a Landsat pixel, 10m x 10m) at points in time. We develop the devices, place a few of them in the field using a computer-aided sampling strategy, observe degradation rates (the approximate change in mass per unit time), develop models, then produce computer maps of these mean, maximum, and minimum rates. The maps are expressions of the integrated forces of degradation.

Justification and Potential Uses:

A market for a commercially-produced substance may be developed. The major uses are:

1. Comparing rates of change in streams or rivers before and after cleanup, building a factory or dam, observing radiation fallout, or the influence of irrigation or storm drain waters.
2. Observing the effects of a weapons-gas attack on an ecosystem.
3. Comparing rates of change in bogs, marshes, or streams, e.g., in Europe and the U.S.
4. Monitoring sewage processing bed suitability of treatment before releasing sewage to a watercourse.
5. Assisting in optimum waste disposal site locations.
6. Assisting in waste and toxic substance clean-up evaluation (i.e., natural vs. induced or post-treatment actions)
7. Predicting changes in certain ecosystems based on past rates of change.
8. Measuring gross changes (increases or decreases) in wildlife and waterfowl marshes (or any area, for that matter) as a result of fire, military vehicle operation, herbicide application, fertilization, or planting of special seeds.
9. Gaining data to enable optimization of turnover rates by various forms of habitat or environmental manipulation.
10. Instructing students in biological and ecological classes to learn of differences in communities, the physiology or functional strength of natural systems, and motivation for learning the reasons for observed differences.
11. Conducting many forms of ecological research, especially on trends in habitats of threatened or endangered species.
12. Observing effects of heavy wildlife foraging on the health or vigor of areas.
13. Determining the time it takes for certain communities (e.g., a pond) to stabilize or achieve a specified rate of change.
14. Assisting in long-term hazard or risk evaluation of contaminants in the field.
15. Suggesting between-area comparisons for allocating scarce resources.

The substance will be useful as an integrative, indicator-substance and is likely to be useful for making many comparisons on military bases and industrial complexes around the world. The substance will provide a standard, gross, wide-range, broad-spectrum, biological-activity indicator. It is not likely to be useful in high-precision studies, it would not likely be useful (except perhaps for selecting sites for instrumentation or sampling stratification), but that is yet to be evaluated.

Significant changes are taking place in forested, farm, suburban, military, and other environments around the world. Some changes are natural, some the result of planned as well as unplanned personnel actions; some are catastrophic, some subtle. It is essential that people keep attuned to these changes for they affect ability to grow crops and forests, to use water, and even to breathe air. They can express before-and-after changes; express effects of cleanup and natural weathering; relate natural to planned efforts; and provide the basis for research, legal action, and education.

Relative change in an object of standard weight may be studied over time. Change in the ecosystem is assumed to be a function of site-specific precipitation, temperature, and solar radiation and other factors. If pollution cleanup (or waste, toxicant, weapon, etc. contamination) is involved, effectiveness may be judged based on restored biological function.

Contaminants of all types tend to be judged harmful because many are lethal. There is genuine long-term concern for the life in the soil and water for many reasons. The reasons vary from those practical and production-oriented (whether it will ever produce crops or trees) (Thomas et al. 1973) to those that are metaphysical. Monitoring of changes in environments is difficult and thus expensive. However, monitoring of such change has become essential. A low-cost and effective means for monitoring changes over wide areas is needed so that comparisons can be made, hazards can be seen, causes detected, trends predicted, and controls initiated to assure an environment of suitable quality for modern people.

A forest, a field, a complex area of military operation, an area to which a pesticide has been applied, even a waste dump, are subject to many factors that influence the changes that take place in the items or substances present. Forest-floor litter has been studied for many years under the concept of decomposition.

The change in the mass of a decomposing, degrading substance is likely to be described well as a linear equation such as

log M = a log (Time + 1).

We may be able to replace T or time in this simplistic empirical relationship of change in mass (M) with cumulative solar radiation (several spectra and shading, S*), and to include the factors of temperature (K) and precipitation (P). These factors are now in a statewide data base and mappable for each land pixel (as mentioned above). Thus, at a site, the differences in the mass of a contaminant after a stated time can be describable as

M = f (K, P, S*).

And we may be able to elaborate this theory fully and relate it to various spatial concepts such as Holdridge's life zones. There are many possible factors involved but we stress that we do not wish to open a research program in the substance, only to use it as an indicator of community activity. Other specific studies may then be conducted if needed, to describe, explain, and predict the causes of the observed changes.

Computer Maps

As a result of past work on computer mapping systems (GIS) and applications such as in powerline location (e.g., Smart 1976) or planned general aviation airports (e.g., Koeln 1980) we have students and new software available in the Conservation Management Institute on campus. McCombs has studied landform. Anderson did regression studies and Gruen (1993) and Klopfer has developed temperature and solar estimates for sites based on the available records for every pixel, given the information at the 5 nearest weather stations to each land pixel.

We have access to data for elevation, slope, aspect and other factors, site-specific, within the region. New analyses of degree-day phenomena (cumulative temperature over various sets of days) may be developed. Duration-of-freezing; time above x-degree centigrade; time since frost; time until frost; time for photosynthesis (for reclamation prescriptions) may be studied and developed later for mapping. We have done extensive studies of the literature. We have information on relations of temperature to ecological, topographic, and physical factors (e.g., simple relations such as cooler temperatures on north-facing slopes). Because of data sources (e.g., often collected at airports or urban weather stations), We cannot afford new, massive, area-wide, long-term data collection. There are regression equations relating soil temperatures to ambient temperatures. With the above ambient temperatures used in these equations, we shall develop probable soil temperature maps.

When the rate of change in a select set of map locations (cells) is known, and these are used as "training cells" so that others with the same environmental characteristics can be deduced to have the same rate, then a full-scale map can be created. We propose to do this in a select area where we already have a database in operation. This will be a demonstration unit, but its relevance may be in selecting waste disposal sites where degradation will occur most rapidly.

As above, stream temperature equations have been reported in the literature relating stream temperature to ambient temperature. We will create and "drape" such stream temperature maps over three-dimensional maps of these areas (as well as make more conventional map displays).

Gruen (1993) found no evidence of global or regional warming in the 30-year record of the Virginia region that she studied. (The rate of change is not significantly different from zero.) The project may be useful in assessing the effects of potential warming.

We have done analyses of about 40 expressions of geomorphology (Martin 1988), e.g., rugosity, circularity. We propose to test whether any of these expressions of landform can improve cell-level temperature estimates or whether they can be used to advantage in an expert system. In summary, we propose to use a comprehensive, mappable knowledge base of the temperatures and other factors of the environment to map expected degradation rates.

Many pesticides and other substances degrade under the influence of ultra-violet and other radiation. The amount of such radiation that each point on the earth receives can be computed. We have completed one Master of Science thesis demonstrating capabilities for mapping solar radiation on irregular surfaces (Lawrence 1976). We propose to repeat and verify this study. A major new development will be to develop an algorithm for estimating the shade resulting from nearby mountains and producing new maps. These maps will include day length, total flux, estimated spectral radiation, and cumulative spectral radiation.

Cloud cover is poorly monitored over the US, and it obviously influences solar radiation. The above work is to develop new, improved estimates of site-specific potential radiation. We know of no way to get cost-effective, long-term cloud cover (as it may affect radiation) over an extended period over a large region. We propose to use a 30-year precipitation record in the same manner as described above for temperature estimates to arrive at a probability-of-cloud cover on a day. Used with the potential estimate, the result will be an expected radiation. Spectral differences (UV and others) potentially relevant in contamination cleanup or breakdown analyses will be analyzes separately.

Solar infrared radiation is a conspicuous relevant component of ambient temperatures. We plan to move past the empirical work on temperature maps to try to develop the local, daily basis for ambient temperature, then add to the model other regional (oceanic) and continental air mass phenomena. We have demonstrated the improved estimators provided by using the gross parameters such as the role of a coastal weather station or data from an interior station that reflects continental air masses. We believe that topographically refined expected solar radiation estimates may significantly improve our estimates (e.g., judged by R2 and PRESS statistics) of temperature at contamination and cleanup sites, those that exist and those for the future, those that are at points or over extensive areas.

Decomposition

Many scientists have studied organic decomposition rates in forests and fields (Van Cleve 1967). Years ago, workers of the AEC (Shanks and Olsen 1961), studying the effects of radioactive fallout on plant and animal communities in the Smoky Mountains, put leaves inside 15 x 15 cm nylon net bags and watched changes in the leaves as caused by the soil micro-arthropods and other ecological factors. The leaves were variable in size, weight, and composition, and thus the variability of their results was high. The technique of the bags may still have usefulness, however; the bag contents must be more uniform to provide suitable comparisons. Giles (1964) used the same bags to evaluate the effects of an aerial application of a pesticide to the total life activity of a forest floor. He had experienced the high costs, technical difficulties, and great variability in carbon-dioxide emission study (Giles 1964, see below). Though of low cost, the nylon-net-bag approach to assessing area change was interesting but resulted in unacceptably high variances from the unstable material, mechanical breakage, material lost from the bag, etc. It was a case of the measurement instrument radically affecting the conditions being measured.

Many techniques have been used to assess forest soil dynamics such as using the rate of carbon dioxide emission as an indicator. I used this with evaluation of Malathion insecticide effects on a forest in 1963 (Giles 1964).

Nylon net bags have been used with rice to measure change in rates of water discharge, and filaments have also been used as an index (Glime and Clemons 1972) often only as an artificial substrate from which organisms are counted. (See also Tatum 1965, Kormondy 1968, and Dickson et al. 1971.) Egglishaw (1969) reported that he had put 10 grams of rice in nylon bags, tossed them into a stream, and used the changed weight as an index of differential stream fertility and health. Other workers have placed forage in nylon bags within the rumen of fistulated ruminants. All of these suggest interest in (and acceptability of the concept of) a means to evaluate the relative rate of change in a major part of an ecosystem.

The literature of modern ecology is replete with discussions and studies of nutrient cycling and energy flow. These studies have suffered from grossness of methods, compartmentalization of research, and difficulties in extrapolating between studies. Known original amounts of nutrients or energy are often lacking. The situation is one needing attention.

These works were the source of the idea which is to develop an artificial "leaf" or "rice," some standard substance that will be very uniform and that will allow improved research into the environment, especially as it is influenced by contaminants and their cleanup or breakdown.

Preliminary Design Criteria

The plastic items are now being designed by Polymer Solutions, Inc., Blacksburg, Virginia, with advice from senior students in Business Management - James Walrod , "John Pope", "Jonathan Shedlosky", "Dustin Rich", and "Adam Marr", supervised by Professors Hatfield and Politis. The items are to be a broad-spectrum, outdoor culture "agar" for decomposers. The selected material may not fit all of the following criteria. If important criteria are impossible to be met by one substance, there may be a need for several items (e.g., one for terrestrial and one for aquatic environments). The substance, tentatively called "ecorods," (or in disk form) and tentatively conceived as a cigarette-size rod or 2 cm x 9-cm wafer (5-10 grams) should, where possible, have the following characteristics (approximate and "desirable":

• Be easily analyzed chemically, i.e., without major equipment or special skills or techniques. (Allen et al. 1975)
• Be of a uniform weight (5-10 grams + <0.01 deviation); have no requirement to weigh the unit before use.
• Have a constant surface area.
• Have constant nutrient contents (± 0.1%).
• Be relatively non-soluble in a stream environment.
• Be non-attractive to rodents or carnivores but attractive to ants, collembola, etc.
• Be consumed by microorganisms and micro-arthropods, aerobes and anaerobes (Weiner et al. 1980).
• Have a non-attractive color; i.e., brown, olive, or gray.
• Cost less than $.50 each. (e.g., 30 samples for $15.00).
• Not float.
• Be useful in deserts, fields and forests (perhaps in aquatic systems).
• Have rates of consumption that will not change or, if so, have an easily operated interpretive PC program to accompany it. Environmental "decay" needs to be readily expressed before an "end point" is reached.
• Be possible to order with a special mix of nutrients (to meet "custom" project needs).
• Be useful worldwide with minimal explanation or training.
• Have an attachment to prevent rapid loss by wind or water.

Notes on Procedures: