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• 1. [Article] Projected land-use change impacts on ecosystem services in the U.S.

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by [publisher] and can be found at: http://www.pnas.org/.

  Citation × Citation Citation Abstract Copy Title: Projected land-use change impacts on ecosystem services in the U.S. Author: Lawler, Joshua J., et al., Lewis, David J., Nelson, Erik This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by [publisher] and can be found at: http://www.pnas.org/. Title: Projected land-use change impacts on ecosystem services in the U.S. Author: Lawler, Joshua J., et al., Lewis, David J., Nelson, Erik This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by [publisher] and can be found at: http://www.pnas.org/. Close

• 2. [Article] Conserving avian diversity in agricultural systems : the role of isolated Oregon white oak legacy trees

  Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks ...

  Citation × Citation Citation Abstract Copy Title: Conserving avian diversity in agricultural systems : the role of isolated Oregon white oak legacy trees Author: DeMars, Craig A. Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks are likely insufficient for long-term conservation of native biodiversity, has necessitated that agricultural systems contribute to conservation of native biota. Current research paradigms have taken a landscape-level view of conservation in agricultural systems, assessing the relative contribution that various habitat elements make in conserving biodiversity in the agricultural matrix. Within this context, I investigated the potential role that individual Oregon white oak (Quercus garryana) trees play in conserving avian diversity in the agricultural systems of the Willamette Valley, Oregon, U.S.A. Retained by landowners primarily for cultural reasons, many of these trees pre-date Euro-American settlement of the Willamette Valley and thus are biological legacies from historic white oak habitats. I compared avian use of isolated white oak trees in three different site contexts - croplands, pastures, and oak savanna reserves - and used an information-theoretic model selection approach to determine the relative importance of site-specific and landscape-level factors thought to influence avian use of these individual trees. Specifically, I tested whether avian species presence on Oregon white oak legacy trees could best be explained by: (i) tree architecture; (ii) the distance of the tree to the nearest tree or patch; (iii) the density of trees in the surrounding landscape; or (iv) the matrix in which the tree was embedded. I evaluated species-specific responses as well as four community-level responses: (i) total bird species richness; (ii) species richness of native birds associated with oak savanna; (iii) species richness of tree foraging birds; and (iv) the combined species richness of aerial- and ground-foraging birds. I sampled 35 individual white oak trees and recorded 47 avian species using these individual trees, including a high number of oak savanna-associated species such White-breasted Nuthatch (Sitta carolinensis) and Chipping Sparrow (Spizella passerina). For the majority of these species, the frequency of use of individual oak trees was similar among crop, pasture and reserve sites. The most important factors for predicting avian use were tree size and tree density in the surrounding landscape. In general, avian use increased with increasing tree size and decreasing tree density. My findings suggest that individual white oak legacy trees have the potential to positively contribute to landscape-level conservation of a wide range of avian species within the Willamette Valley. Due to the declining abundance of white oak legacy trees on the landscape, the conservation of existing legacy trees and the recruitment of younger replacement trees should be a management priority. Title: Conserving avian diversity in agricultural systems : the role of isolated Oregon white oak legacy trees Author: DeMars, Craig A. Over one third of the earth’s land surface has been modified to some extent for agricultural purposes. The large global footprint of agriculture, combined with the knowledge that existing reserve networks are likely insufficient for long-term conservation of native biodiversity, has necessitated that agricultural systems contribute to conservation of native biota. Current research paradigms have taken a landscape-level view of conservation in agricultural systems, assessing the relative contribution that various habitat elements make in conserving biodiversity in the agricultural matrix. Within this context, I investigated the potential role that individual Oregon white oak (Quercus garryana) trees play in conserving avian diversity in the agricultural systems of the Willamette Valley, Oregon, U.S.A. Retained by landowners primarily for cultural reasons, many of these trees pre-date Euro-American settlement of the Willamette Valley and thus are biological legacies from historic white oak habitats. I compared avian use of isolated white oak trees in three different site contexts - croplands, pastures, and oak savanna reserves - and used an information-theoretic model selection approach to determine the relative importance of site-specific and landscape-level factors thought to influence avian use of these individual trees. Specifically, I tested whether avian species presence on Oregon white oak legacy trees could best be explained by: (i) tree architecture; (ii) the distance of the tree to the nearest tree or patch; (iii) the density of trees in the surrounding landscape; or (iv) the matrix in which the tree was embedded. I evaluated species-specific responses as well as four community-level responses: (i) total bird species richness; (ii) species richness of native birds associated with oak savanna; (iii) species richness of tree foraging birds; and (iv) the combined species richness of aerial- and ground-foraging birds. I sampled 35 individual white oak trees and recorded 47 avian species using these individual trees, including a high number of oak savanna-associated species such White-breasted Nuthatch (Sitta carolinensis) and Chipping Sparrow (Spizella passerina). For the majority of these species, the frequency of use of individual oak trees was similar among crop, pasture and reserve sites. The most important factors for predicting avian use were tree size and tree density in the surrounding landscape. In general, avian use increased with increasing tree size and decreasing tree density. My findings suggest that individual white oak legacy trees have the potential to positively contribute to landscape-level conservation of a wide range of avian species within the Willamette Valley. Due to the declining abundance of white oak legacy trees on the landscape, the conservation of existing legacy trees and the recruitment of younger replacement trees should be a management priority. Close

• 3. [Article] Building on Two Decades of Ecosystem Management and Biodiversity Conservation under the Northwest Forest Plan, USA

  Correction: We discovered two typos and a change in a sentence needed in our published manuscript. Regarding the typos: timber estimates in Section 2 of the NWFP’s Long-Term Objectives should have been ...

  Citation × Citation Citation Abstract Copy Title: Building on Two Decades of Ecosystem Management and Biodiversity Conservation under the Northwest Forest Plan, USA Author: DellaSala, Dominick A., Baker, Rowan, Heiken, Doug, Nelson, S. Kim, et al. Correction: We discovered two typos and a change in a sentence needed in our published manuscript. Regarding the typos: timber estimates in Section 2 of the NWFP’s Long-Term Objectives should have been 2.34 million cubic meters annually instead of 234 million cubic meters annually and ~1.78 million cubic meters instead of 178 million cubic meters annually. The statement regarding murrelet populations—“Trends were downward (but not significant) in other NWFP states” should be deleted in this paper [1]. The authors would like to apologize for any inconvenience caused to the readers by these changes. Title: Building on Two Decades of Ecosystem Management and Biodiversity Conservation under the Northwest Forest Plan, USA Author: DellaSala, Dominick A., Baker, Rowan, Heiken, Doug, Nelson, S. Kim, et al. Correction: We discovered two typos and a change in a sentence needed in our published manuscript. Regarding the typos: timber estimates in Section 2 of the NWFP’s Long-Term Objectives should have been 2.34 million cubic meters annually instead of 234 million cubic meters annually and ~1.78 million cubic meters instead of 178 million cubic meters annually. The statement regarding murrelet populations—“Trends were downward (but not significant) in other NWFP states” should be deleted in this paper [1]. The authors would like to apologize for any inconvenience caused to the readers by these changes. Close