<i>Response</i>
            : Factors in Summer Ozone Production in the San Francisco Air Basin

Sandberg, James S.; Basso, M. J.; Okin, B. A.

doi:10.1126/science.203.4375.82

Cited by 6 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Starting in 1975 north coast "oxidant" values refer to ozone only. Sandberg et al (1979) found that this resulted in a 2% change in readings on the average. Synergistic indices were developed based on the enhanced plant damage noted in the literature, mostly for crop species, when ozone and S02 , or N02 and S02 occur together.…”

Section: Methods Of Data Collectionmentioning

confidence: 98%

Diversity Relations and Succession in Californian Coastal Sage Scrub

Westman¹

1981

Ecology

149

View full text Add to dashboard Cite

The facultatively drought—deciduous shrublands of coastal California and Baja California are lowest in species richness of the four Mediterranean—climate regions where this physiognomic type occurs. Alpha richness in the North American coastal sage scrub varies primarily with the abundance of herbaceous annual species. Herb levels in turn vary with differences in levels of precipitation, favorableness of temperature during the winter and spring growing season, shading by shrubs, soil nitrogen, and air pollution. Levels of herbaceous annuals are highest in the growing season following fire, and show a second pulse of abundance in stands 15—25 yr old. Mature stands of coastal sage scrub are typically low in species equitability, due at least in part to the shade—intolerance of the herbaceous understory and to reduced levels of soil nitrogen. Symbiotic nitrogen—fixing organisms are virtually absent from stands which have not burned in 20 yr or more. The pattern of postfire succession varies markedly with fire intensity; dominant shrubs sprout abundantly from root crowns only following less intense fires. While there are °50 widespread sage scrub species, more than half of the 375 species encountered in the present study of the sage scrub flora are rare in occurrence within the habitat range. In view of the reduction of the area of coastal sage scrub in California to 10—15% of its former extent and the limited extent of preserves, measures to conserve the diversity of the flora are needed.

show abstract

Section: Methods Of Data Collectionmentioning

confidence: 98%

Diversity Relations and Succession in Californian Coastal Sage Scrub

Westman¹

1981

Ecology

149

View full text Add to dashboard Cite

show abstract

Air pollution injury to coastal sage scrub in the Santa Monica Mountains, Southern California

Westman

1985

Water Air Soil Pollut

View full text Add to dashboard Cite

Radiocarbon Measurements of Particulates in Smog

1983

View full text Add to dashboard Cite

In recent years in California, smog aerosols have been observed in metropolitan and rural areas. We wondered what the relative contribution is from sources such as fossil fuel combustion (eg, cars, factories) and emissions from trees and other plants. Pollution produced by fossil fuel combustion can be distinguished from biological sources using radioactive carbon. Carbon in fossil organic materials is radioactively dead whereas carbon in living plants contains 14C. Smog particles were collected on clean glass or quartz fiber paper and analyzed in a small volume CO2 proportional counter for 14C content. Results are given for sampling locations at UCLA, El Monte, Riverside, and Lake Tahoe showing the relative contributions of fossil and modern carbon sources ranging from 0 to 74% and 26 to 100% respectively.

show abstract

Response : Factors in Summer Ozone Production in the San Francisco Air Basin

Cited by 6 publications

References 2 publications

Diversity Relations and Succession in Californian Coastal Sage Scrub

Diversity Relations and Succession in Californian Coastal Sage Scrub

Air pollution injury to coastal sage scrub in the Santa Monica Mountains, Southern California

Radiocarbon Measurements of Particulates in Smog

Contact Info

Product

Resources

About