@article {753,
	title = {Human impacts, plant invasion, and imperiled plant species in California},
	journal = {Ecological Applications},
	volume = {16},
	year = {2006},
	month = {2006},
	pages = {1338-1350},
	abstract = {Invasive species are one of the fastest growing conservation problems. These species homogenize the world{\textquoteright}s flora and fauna, threaten rare and endemic species, and impose large economic costs. Here, we examine the distribution of 834 of the more than 1000 exotic plant taxa that have become established in California, USA. Total species richness increases with productivity; however, the exotic flora is richest in low-lying coastal sites that harbor large numbers of imperiled species, while native diversity is highest in areas with high mean elevation. Weedy and invasive exotics are more tightly linked to the distribution of imperiled species than the overall pool of exotic species. Structural equation modeling suggests that while human activities, such as urbanization and agriculture, facilitate the initial invasion by exotic plants, exotics spread ahead of the front of human development into areas with high numbers of threatened native plants. The range sizes of exotic taxa are an order of magnitude smaller than for comparable native taxa. The current small range size of exotic species implies that California has a significant {\textquoteleft}{\textquoteleft}invasion debt{\textquoteright}{\textquoteright} that will be paid as exotic plants expand their range and spread throughout the state.},
	keywords = {California, dispersal, exotic plants, extinction, global biodiversity hotspot, habitat loss, invasive species, rare species, species richness, structural equation models},
	url = {http://www.esajournals.org/esaonline/?request=get-abstract\&issn=1051-0761\&volume=016\&issue=04\&page=1338},
	author = {Seabloom, E. W. and Williams, J. W. and Slayback, D. and Stoms, D. M. and Viers, J. H. and Dobson, A. P.}
}
@article {832,
	title = {Anthropogenic impacts upon plant species richness and NPP in California},
	journal = {Ecology Letters},
	volume = {8},
	year = {2005},
	month = {2005},
	pages = {127-137},
	abstract = {We assess the importance of anthropogenic land-use, altered productivity, and species invasions for observed productivity-richness relationships in California. To this end, we model net primary productivity (NPP) c. 1750 AD and at present (1982-1999) and map native and exotic vascular plant richness for 230 subecoregions. NPP has increased up to 105\% in semi-arid areas and decreased up to 48\% in coastal urbanized areas. Exotic invasions have increased local species diversity up to 15\%. Human activities have reinforced historical gradients in species richness but reduced the spatial heterogeneity of NPP. Structural equation modelling suggests that, prior to European settlement, NPP and richness were primarily controlled by precipitation and other abiotic variables, with NPP mediating richness. Abiotic variables remain the strongest predictors of present NPP and richness, but intermodel comparisons indicate a significant anthropogenic impact upon statewide distributions of NPP and richness. Exotic and native species each positively correlate to NPP after controlling for other variables, which may help explain recent reports of positively associated native and exotic richness.},
	keywords = {California, human impacts, Land cover change, net primary productivity, species richness, structural equation models},
	url = {<Go to ISI>://000226491200001},
	author = {Williams, J. W. and Seabloom, E. W. and Slayback, D. and Stoms, D. M. and Viers, J. H.}
}
@article {790,
	title = {Potential NDVI as a baseline for monitoring ecosystem functioning},
	journal = {International Journal of Remote Sensing},
	volume = {21},
	year = {2000},
	month = {2000},
	pages = {401-407},
	abstract = {Baseline data are needed to determine the overall magnitude and direction of change in ecosystem functioning. This letter presents an approach to estimate potential NDVI from environmental variables and training data of actual NDVI in nature reserves. Patterns of deviations of actual NDVI from the baseline generally correspond with land-use types in the western United States.},
	keywords = {AVHRR, California, GAP, managed areas, NDVI, net primary production, NPP, Oregon, regression tree analysis, time integrated NDVI, Washington},
	url = {<Go to ISI>://000084681200014},
	author = {Stoms, D. M. and Hargrove, W. W.}
}
@inbook {395,
	title = {Selecting biodiversity management areas},
	booktitle = {Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options},
	year = {1996},
	pages = {1503-1528},
	publisher = {University of California, Centers for Water and Wildlands Resources},
	organization = {University of California, Centers for Water and Wildlands Resources},
	address = {Davis, California},
	abstract = {Here we present and evaluate a conservation strategy whose objective is to represent all native plant communities in areas where the primary management goal is to sustain native biodiversity. We refer to these areas as Biodiversity Management Areas (BMAs), which we define as specially designated public or private lands with an active ecosystem management plan in operation whose purpose is to contribute to regional maintenance of native genetic, species and community levels of biodiversity, and the processes that maintain that biodiversity. Our purpose in this chapter is to explore opportunities for siting BMAs in the Sierra Nevada region. The strategic goal is to design a BMA system that represents all major Sierran plant community types, which we use as a coarse surrogate for ecosystems and their component species. We consider a community type to be represented if some pre-defined fraction of its mapped distribution occurs in one or more BMAs. We use a multi-objective computer model to allocate a minimum of new land to BMA status subject to the constraints that all community types must be represented, and that the new BMA areas should be located in areas of highest suitability for BMA status. Our purpose in this exercise is not to identify the optimal sites for a Sierran BMA system; instead it is to measure some of the likely dimensions of plausible, alternative BMA systems for the Sierra Nevada and to develop a rationale that would guide others in formulating such a system. Thus we examine a wide range of possible BMA systems based on different assumptions, constraints, target levels for representation, and priorities. If one ignores current land ownership and management designations and sets out to represent plant communities in a BMA system based on Calwater planning watersheds (which average roughly 10,000 acres in size), an efficient BMA system requires land in direct proportion to the target level, at least over the range of target levels examined in this study. In other words, it takes roughly 10\% of the region to meet a 10\% goal, and 25\% of the region to meet a 25\% goal. The pattern of selected watersheds is very different from the current distribution of parks and wilderness areas, which are concentrated at middle and high elevations in the central and southern portion of the range. Public lands alone are insufficient to create a BMA system that adequately represents all plant community types of the Sierra Nevada. Many of the foothill community types occur almost exclusively on private lands. Terrestrial vertebrates are reasonably well represented in a BMA system selected for plant communities. A BMA system selected for vertebrates alone, however, has little overlap with the one for plant communities. Areas selected by the BMAS model show only a modest amount of overlap with areas selected by other SNEP working groups as focal areas for conserving aquatic biodiversity or late successional/old growth forests. However, the BMAS model can be formulated to favor these areas with little loss of efficiency, especially in the northern Sierra.},
	keywords = {biodiversity management area, BMAS model, California, representation, reserve selection, Sierra Nevada},
	author = {Davis, F. W. and Stoms, D. M. and Church, R. L. and Okin, W. J. and Johnson, K. N.}
}
@inbook {392,
	title = {Sierran vegetation: A gap analysis},
	booktitle = {Sierra Nevada Ecosystem Project: Final Report to Congress, vol. II, Assessments and scientific basis for management options},
	year = {1996},
	pages = {671-689},
	publisher = {University of California, Centers for Water and Wildlands Resources},
	organization = {University of California, Centers for Water and Wildlands Resources},
	address = {Davis, California},
	abstract = {Gap analysis assesses the distribution of plant community types and vertebrate species distributions among land classes defined by ownership and levels of protection of biodiversity. Gap analysis helps to identify which plant communities and species might be especially vulnerable to different human activities that can lead to habitat conversion or degradation. This chapter presents a gap analysis of plant community types the Sierra Nevada region, an area of 63,111 km2 (24,368 mi2). Ownership of the region is 37\% private, 47\% national forests, 10\% national parks, 5\% Bureau of Land Management, and less than 2\% in other public lands. Land ownership and land management patterns contrast sharply between the northern Sierra Nevada versus the central and southern subregions. Parks and reserve lands contribute less than 2\% of the northern region versus 27\% of the central/southern. We mapped eighty-eight natural plant community types within the region. Sixty-seven types were mapped over areas greater than 25 km2 (9.65 mi2). The ownership profiles of Sierran plant communities systematically reflect the concentration of private lands at lower elevations and of national parks in the central and southern portion of the range. Less than 1\% of the foothill woodland zone of the Sierra Nevada is in designated reserves or other areas managed primarily for native biodiversity, and over 95\% of the distribution of most foothill community types is available for grazing. Low to middle elevation Sierran forests are not well represented in designated reserves, especially in the northern Sierra Nevada. However, large areas of most of these forest types on U.S. Forest Service lands have been administratively withdrawn from intensive timber management based on current forest plans. Many high-elevation forest and shrubland community types are well represented in parks and ungrazed wilderness areas. Our analysis identifies thirty-two widespread community types whose conservation status warrants concern and twelve types that appear well protected based on their present distributions.},
	keywords = {California, gap analysis, land management, Sierra Nevada, vegetation},
	author = {Davis, F. W. and Stoms, D. M.}
}
@article {389,
	title = {Gap analysis of the actual vegetation of California: 1. The Southwestern Region},
	journal = {Madrono},
	volume = {42},
	number = {1},
	year = {1995},
	pages = {40-78},
	abstract = {Gap Analysis is a method of conservation risk assessment that evaluates the protection status of plant communities, animal species and vertebrate species richness by overlay of biological distribution data on a map of existing biological reserves. The National Biological Survey has undertaken a national Gap Analysis that is being conducted by individual states but that will eventually produce regional and national assessments. Given California{\textquoteright}s size and complexity, we are conducting separate Gap Analyses for each of the state{\textquoteright}s 10 ecological regions, as delineated in The Jepson Manual. Here we summarize our findings on the distribution of plant communities and dominant plant species in the Southwestern Region of California, exclusive of the Channel Islands. We tabulate and discuss regional distribution patterns, management status and patterns of land ownership for 76 dominant woody species and 62 natural communities. Nineteen of 62 mapped communities appear to be at risk, as determined by their poor representation in existing reserves, parks or wilderness areas. Communities restricted largely to the lower elevations, such as non-native grasslands and coastal sage scrub types, are clearly at considerable risk. A majority of the lands at these elevations have already been converted to agricultural or urban uses and most of the remaining lands are threatened with future urbanization. Areas that appear to be of highest priority for conservation action based on agreement between our analysis and a recent assessment by The Nature Conservancy include the Santa Margarita River, San Mateo Creek, Miramar Mesa, Santa Clara floodplain near Fillmore, Sespe and Piru Canyons, and Tejon Pass.},
	keywords = {California, gap analysis, vegetation},
	author = {Davis, F. W. and Stine, P. A. and Stoms, D. M. and Borchert, M. I. and Hollander, A. D.}
}
