Introduction-global to local: Ecological Land Classification.

Ecological Land Classification (ELC) is a scientific endeavour which attempts to organize, stratify and evaluate ecosystems (and complexes of ecosystems) for the purposes of land resource management. Since ecosystems themselves are not easily defined in practical terms, ELC is likewise not a trivial concept. Nonetheless, ELC is a prerequisite for ecosystem management and the conservation of biological diversity simply because ecosystems must be described, characterized and spatially-located before they can be managed. Regarding the current status and future direction of ELC, mainly in relation to forest management: 1) approaches to ELC construction and utilization have shifted considerably over the past 2 decades; 2) there appears to be a current consensus regarding basic approaches to ELC; 3) spatial scale is a critical variable that must be addressed by ELCs; 4) ELCs must strive to more directly address management objectives; 5) natural ecosystem functions need to be better integrated within ELC frameworks; and, 6) the need for quality, georeferenced ELC-related data will continue to grow.

Primary databases for forest ecosystem management-examples from Ontario and possibilities for Canada: NatGRID.

This paper identifies some scientific impediments to ecosystem management and describes bio-physical databases required to help systematically and empirically address the ecological sustainability challenge. Examples are drawn from ongoing work in Ontario. This work has implications for efforts in ecological land classification, landscape ecology, more efficient locating of research and monitoring plots, wildlife management and ultimately trade-off analyses. We conclude with the recommendation that the key primary databases, as currently evolving for Ontario, could and should be developed nationally, thereby creating a "NatGRID database", i.e., Nationally Georeferenced Resource Information for Decision-making. NatGRID could be used to help address, in a more quantitative manner, fundamental questions regarding ecological sustainability and trade-offs in forest management.

Tree species in relation to soil moisture regime in northwestern Ontario, Canada.

Selected data on site, vegetation cover, and soil, including soil moisture regime (SMR), were collected from 2 167 field plots in northwestern Ontario, Canada. SMR provides an estimate of an averaged, "annualized" soil moisture supply throughout a complete vegetation cycle. SMR is based upon a relative scale that subjectively ranks sites from θ, 0, and 1 through 9 along a soil moisture continuum which relates to a dry to wet gradient. SMR may be generally correlated to tree growth, stand composition, degree of competition, nutrient availability and overall site quality.This paper reports on relationships between SMR and major tree species. Results highlight relationships between SMR class and the broad ecological ranges of several tree species. In northwestern Ontario, the determination of SMR can help resource managers to better understand the ecology of boreal sites.

Murine tumor induction by cytomegalovirus.

Cytomegalic inclusion disease can be induced in mice with relative ease. In the study reported here, grandular neoplasms were produced in four mice by means of immunosupression together with large doses of cytomegalovirus. The results of this study suggest that cytomegalovirus may well be an etiologic agent in the formation of salivary gland tumors.

Isolation of St. Louis encephalitis virus from bats (Tadarida b. mexicana) in Texas.

A strain of St. Louis encephalitis virus has been isolated from Mexican free-tailed bats (Tadarida b. mexicana) collected at the time of an outbreak of encephalitis in Texas in 1964.