Filters: Contacts: V. Thomas Parker (X)
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Arctostaphylos is richly diverse and taxonomically challenging. Unequivocal fossils appear as far back as the middle Miocene. Many pulses of diversification and decimation may have taken place in the genus since then; evidence suggests that there has been a rapid radiation in the last 1.5 million years. Some morphological features are not clearly differentiated among taxa and appear to be mosaically distributed.Multiple lines of evidence suggest that Arctostaphylos is a terminal branch within Arbutoideae. Arctous is treated here as a separate genus, as it is likely sister to Arctostaphylos. Only one species of Arctostaphylos, A. uva-ursi, is found outside of western North America, Mexico, and Guatemala. Taxa are...
Categories: Publication;
Types: Citation
Ecological factors favoring either postfire resprouting or postfire obligate seeding in plants have received considerable attention recently. Three ecological models have been proposed to explain patterns of these two life history types. In this study, we test these three models using data from California chaparral. We take an innovative approach to testing these models by not testing community or landscape patterns, but instead, investigating vegetation structure characteristic of four pairs of resprouting and (non-resprouting) obligate seeding subspecies of Arctostaphylos (Ericaceae), a dominant and diverse shrub genus in California chaparral. Data were analyzed for percentage bare ground, elevation, annual precipitation,...
There is value in understanding the past and how it has affected the present. Science focuses on empirical findings, and we know that our prior experiences and those of our predecessors play important roles in determining how we interpret the present. We learn from accomplishments and foibles of predecessors and appreciate the real life experiences we have gone through. In our studies of the genus Arctostaphylos Adans. we have been struck by the fascinating stories surrounding taxonomists who have played roles in the development of our current understanding of the group. In addition to providing insights, they sometimes provide humor and lessons on the value of competition versus collaboration. We offer this history...
One of the most dynamic California ecosystems is chaparral. Dominated by evergreen, sclerophyllous shrubs and small trees, chaparral is the most extensive vegetation type in the state (Figure 1). The nearly impenetrable tangle of stiff branches of this unusual vegetation inhibits exploration, and as a consequence the public know little about its natural history and unique characteristics. This under-valued ecosystem is recognized instead by the threat of its extensive, high-intensity canopy-burning wildfires that characterize the dry summer and fall seasons of the state. Because urban areas frequently share borders or intermix with chaparral, societal interests often conflict with conservation of this ecosystem,...
Categories: Publication;
Types: Citation
Remote sensing based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in conducting greenhouse gas inventories and implementing climate mitigation policies. Our objective was to generate a single remote sensing model of tidal marsh aboveground biomass and carbon that represents nationally diverse tidal marshes within the conterminous United States (CONUS). To meet this objective we developed the first national-scale dataset of aboveground tidal marsh biomass, species composition, and aboveground plant carbon content (%C) from six CONUS regions: Cape Cod, MA, Chesapeake Bay, MD, Everglades, FL, Mississippi Delta, LA, San Francisco Bay, CA, and Puget Sound, WA....
Categories: Data;
Tags: C-band synthetic aperture radar,
Cape Cod,
Chesapeake Bay,
National greenhouse gas inventory,
Puget Sound,
Changes are made in the nomenclature of species and subspecies in the genus Arctostaphylos(Ericaceae). In this study, the focus is on species found in the coast ranges of California. Changes are made in A. nortensis from the area around the Oregon border with California, in the A. nevadensiscomplex in the North Coast Ranges, in the A. nummularia complex of the north to central coast, in the A. tomentosa complex of the central coast to the Channel Islands, and in the A. hookeri and A. pilosula complex of the central coast. Also discussed are other changes presented elsewhere that will affect the Arctostaphylos treatment in the next edition of the Jepson Manual.
Remote sensing based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in conducting greenhouse gas inventories and implementing climate mitigation policies. Our objective was to generate a single remote sensing model of tidal marsh aboveground biomass and carbon that represents nationally diverse tidal marshes within the conterminous United States (CONUS). To meet this objective we developed the first national-scale dataset of aboveground tidal marsh biomass, species composition, and aboveground plant carbon content (%C) from six CONUS regions: Cape Cod, MA, Chesapeake Bay, MD, Everglades, FL, Mississippi Delta, LA, San Francisco Bay, CA, and Puget Sound, WA....
Categories: Data;
Tags: C-band synthetic aperture radar,
Cape Cod,
Carbon sequestration,
Chesapeake Bay,
Everglades National Park,
The genus Arctostaphylos consists mostly of chaparral shrubs known by the common name manzanita, and one of the widest ranging of these is A. glandulosa Eastw., distributed from Baja California to Oregon. Particularly in the southern half of its range it exhibits complex patterns of morphological variation that have long presented taxonomic challenges. Phenetic analysis of morphological traits from over 1400 individuals from throughout the range were used to examine intra- and inter-population patterns of variation. Multivariate ordination and hierarchical cluster analysis were used to determine phenetic patterns linked with ecological and geographical distributions. These analyses suggest the hypothesis that this...
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