Anthony R. Olsen

TL;DR: In this paper, a unified strategy for selecting spatially balanced probability samples of natural resources is presented, which is based on creating a function that maps two-dimensional space into onedimensional space, thereby defining an ordered spatial address.

TL;DR: In this paper, a unified strategy for designing probability samples of discrete, finite resource populations, such as lakes within some geographical region; linear populations such as a stream network in a drainage basin, and continuous, two-dimensional populations, including forests, is presented.

TL;DR: A summary of existing programs' statistical designs and potential alternatives for improvement in national monitoring, leading to comprehensive monitoring in the United States are presented.

Abstract: The Wadeable Streams Assessment (WSA) provided the first statistically sound summary of the ecological condition of streams and small rivers in the US. Information provided in the assessment filled an important gap in meeting the requirements of the US Clean Water Act. The purpose of the WSA was to: 1) report on the ecological condition of all wadeable, perennial streams and rivers within the conterminous US, 2) describe the biological condition of these systems with direct measures of aquatic life, and 3) identify and rank the relative importance of chemical and physical stressors affecting stream and river condition. The assessment included perennial wadeable streams and rivers that accounted for 95% of the length of flowing waters in the US. The US Environmental Protection Agency, states, and tribes collected chemical, physical, and biological data at 1392 randomly selected sites. Nationally, 42% of the length of US streams was in poor condition compared to best available reference sites in the...

TL;DR: In this paper, the authors present a unified approach that addresses the differences of the aquatic resources assuming the availability of frame material, such as Geographic Information System (GIS) coverages of the boundary for coastal waters, stream network, and lake locations from U.S. Environmental Protection Agency's River Reach File 3.