Logging and soil nutrients independently explain plant trait expression in tropical forests

We acknowledge financial support by the UK Natural Environment Research Council (NE/K016253/1), with additional support through an ERC Advanced Investigator Award to YM (GEM-TRAIT; 321131). We are indebted to the Sabah Biodiversity Council, Yayasan Sabah, the Maliau Basin and Danum Valley Management Committees, the Institute for Tropical Biology and Conservation at the University of Malaysia, Sabah, and the Sabah Forest Research Centre at Sepilok. We thank Glen Reynolds and the South East Asia Rainforest Research Partnership (SEARRP). This study was supported by funding from the Sime Darby Foundation to the Stability of Altered Forest Ecosystems (SAFE) Project. This project would not have been possible without the indispensable support from dozens of research assistants in Sabah. The support from Laura Kruitbos, Unding Jami, Lisa P. Bentley, Benjamin Blonder, Puikiat Hoo, Palasiah Jotan, Alexander Shenkin and Chun Xing Wong is gratefully acknowledged. We thank Bernadus Bala Ola, Bill McDonald, Alexander Karolus and MinSheng Khoo for species identification. This publication is a contribution from the UK NERC-funded Biodiversity And Land-use Impacts on Tropical Ecosystem Function (BALI) consortium (http://bali.hmtf.info) through its Human Modified Tropical Forests thematic programme.Peer reviewedPostprin

Covariance of sun and shade leaf traits along a tropical forest elevation gradient

Foliar trait adaptation to sun and shade has been extensively studied in the context of photosynthetic performance of plants, focusing on nitrogen allocation, light capture and use via chlorophyll pigments and leaf morphology; however, less is known about the potential sun-shade dichotomy of other functionally important foliar traits. In this study, we measured 19 traits in paired sun and shade leaves along a 3,500-m elevation gradient in southern Peru to test whether the traits differ with canopy position, and to assess if relative differences vary with species composition and/or environmental filters. We found significant sun-shade differences in leaf mass per area (LMA), photosynthetic pigments (Chl ab and Car), and δ13C. Sun-shade offsets among these traits remained constant with elevation, soil substrates, and species compositional changes. However, other foliar traits related to structure and chemical defense, and those defining general metabolic processes, did not differ with canopy position. Our results suggest that whole-canopy function is captured in many traits of sun leaves; however, photosynthesis-related traits must be scaled based on canopy light extinction. These findings show that top-of-canopy measurements of foliar chemistry from spectral remote sensing approaches map directly to whole-canopy foliar traits including shaded leaves that cannot be directly observed from above.Fil: Martin, Roberta E.. Arizona State University; Estados UnidosFil: Asner, Gregory P.. Arizona State University; Estados UnidosFil: Bentley, Lisa Patrick. Sonoma State University; Estados UnidosFil: Shenkin, Alexander. University of Oxford; Reino UnidoFil: Salinas, Norma. Oxford Social Sciences Division; Reino Unido. Pontificia Universidad Católica de Perú; PerúFil: Huaypar, Katherine Quispe. Universidad Nacional San Antonio Abad del Cusco; PerúFil: Pillco, Milenka Montoya. Universidad Nacional San Antonio Abad del Cusco; PerúFil: Ccori Álvarez, Flor Delis. Universidad Nacional San Antonio Abad del Cusco; PerúFil: Enquist, Brian J.. University of Arizona; Estados UnidosFil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Malhi, Yadvinder. University of Oxford; Reino Unid

Scale dependence of canopy trait distributions along a tropical forest elevation gradient

Average responses of forest foliar traits to elevation are well understood, but far less is known about trait distributional responses to elevation at multiple ecological scales. This limits our understanding of the ecological scales at which trait variation occurs in response to environmental drivers and change. We analyzed and compared multiple canopy foliar trait distributions using field sampling and airborne imaging spectroscopy along an Andes-to-Amazon elevation gradient. Field-estimated traits were generated from three community-weighting methods, and remotely sensed estimates of traits were made at three scales defined by sampling grain size and ecological extent. Field and remote sensing approaches revealed increases in average leaf mass per unit area (LMA), water, nonstructural carbohydrates (NSCs) and polyphenols with increasing elevation. Foliar nutrients and photosynthetic pigments displayed little to no elevation trend. Sample weighting approaches had little impact on field-estimated trait responses to elevation. Plot representativeness of trait distributions at landscape scales decreased with increasing elevation. Remote sensing indicated elevation-dependent increases in trait variance and distributional skew. Multiscale invariance of LMA, leaf water and NSC mark these traits as candidates for tracking forest responses to changing climate. Trait-based ecological studies can be greatly enhanced with multiscale studies made possible by imaging spectroscopy.Fil: Asner, Gregory P.. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Martin, Roberta E.. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Anderson, Christopher Brian. Carnegie Institution for Science. Department of Global Ecology; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kryston, Katherine. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Vaughn, Nicholas. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Knapp, David E.. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Bentley, Lisa Patrick. University of Oxford; Reino UnidoFil: Shenkin, Alexander. University of Oxford; Reino UnidoFil: Salinas, Norma. University of Oxford; Reino Unido. Pontificia Universidad Católica de Perú; PerúFil: Sinca, Felipe. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Tupayachi, Raul. Carnegie Institution for Science. Department of Global Ecology; Estados UnidosFil: Quispe Huaypar, Katherine. Universidad Nacional de San Antonio Abad del Cusco; PerúFil: Montoya Pillco, Milenka. Universidad Nacional de San Antonio Abad del Cusco; PerúFil: Ccori Álvarez, Flor Delis. Universidad Nacional de San Antonio Abad del Cusco; PerúFil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Enquist, Brian J.. Arizona State University; Estados UnidosFil: Malhi, Yadvinder. University of Oxford; Reino Unid