Long-term ecological monitoring

The intent of long-term ecological monitoring is to document changes in important properties of biological communities. At the least, a long-term monitoring system should be designed to detect long-term trends in three key attributes: soil and site stability, hydrologic function, and the biotic integrity of the system. There are four basic guidelines for developing integrated soil-vegetation monitoring systems for rangelands. These are: (1) identifying a suite of indicators which are consistently correlated with the functional status of one or more critical ecosystem processes and/or properties; (2) selecting base indicators on site specific objectives and resource concerns, and inherent soil and site characteristics; (3) using spatial variability in developing and interpreting indicators to make them more representative of ecological processes; and (4) interpreting indicators in the context of an understanding of dynamic, nonlinear ecological processes. To the extent possible, indicators should reflect early changes in ecological processes and indicate that a more significant change is likely to occur. In addition to these guidelines, measurements included in long-term monitoring systems should be rapidly applied, simple to understand, inexpensive to use, and quantitatively repeatable.