Climate refugia for Pinus spp. in topographic and bioclimatic environments of the Madrean sky islands of México and the United States
Tóm tắt
Climate refugia, or places where habitats are expected to remain relatively buffered from regional climate extremes, provide an important focus for science and conservation planning. Within high-priority, multi-jurisdictional landscapes like the Madrean sky islands of the United States and México, efforts to identify and manage climate refugia are hindered by the lack of high-quality and consistent transboundary datasets. To fill these data gaps, we assembled a bi-national field dataset (n = 1416) for five pine species (Pinus spp.) and used generalized boosted regression to model pine habitats in relation to topographic variability as a basis for identifying potential microrefugia at local scales in the context of current species’ distribution patterns. We developed additional models to quantify climatic refugial attributes using coarse scale bioclimatic variables and finer scale seasonal remote sensing indices. Terrain metrics including ruggedness, slope position, and aspect defined microrefugia for pines within elevation ranges preferred by each species. Response to bioclimatic variables indicated that small shifts in climate were important to some species (e.g., P. chihuahuana, P. strobiformis), but others exhibited a broader tolerance (e.g., P. arizonica). Response to seasonal climate was particularly important in modeling microrefugia for species with open canopy structure and where regular fires occur (e.g., P. engelmannii and P. chihuahuana). Hotspots of microrefugia differed among species and were either limited to northern islands or occurred across central or southern latitudes. Mapping and validation of refugia and their ecological functions are necessary steps in developing regional conservation strategies that cross jurisdictional boundaries. A salient application will be incorporation of climate refugia in management of fire to restore and maintain pine ecology. Una versión en español de este artículo está disponible como descarga.
Tài liệu tham khảo
Aburto-Oropeza O, Johnson AF, Agha M, Allen EB, Allen MF, González JA, Moreno DM, Beas-Luna R, Butterfield S, Caetano G, Caselle JE et al (2018) Harnessing cross-border resources to confront climate change. Environ Sci Policy 87:128–132. https://doi.org/10.1016/J.ENVSCI.2018.01.001
Adams DK, Comrie AC (1997) The North American monsoon. Bull Am Meteorol Soc 78(10):2197–2214
AdaptWest Project (2015) Gridded current and projected climate data for North America at 1 km resolution, interpolated using the ClimateNA v5.10 software. https://adaptwest.databasin.org/pages/adaptwest-climatena. Accessed 28 Mar 2022
Aguirre-Gutiérrez J, Serna-Chavez HM, Villalobos-Arambula AR, Pérez de la Rosa JA, Raes N (2015) Similar but not equivalent: ecological niche comparison across closely-related Mexican white pines. Divers Distrib 21(3):245–257. https://doi.org/10.1111/ddi.12268
Andrews C, Weiskittel A, D’Amato AW, Simons-Legaard E (2018) Variation in the maximum stand density index and its linkage to climate in mixed species forests of the North American Acadian Region. For Ecol Manage 417:90–102
Araújo MB, Guisan A (2006) Five (or so) challenges for species distribution modelling. J Biogeogr 33(10):1677–1688. https://doi.org/10.1111/j.1365-2699.2006.01584.x
Ashcroft MB (2010) Identifying refugia from climate change. J Biogeogr 37(8):1407–1413. https://doi.org/10.1111/j.1365-2699.2010.02300.x
Ashcroft MB, Chisholm LA, French KO (2009) Climate change at the landscape scale: predicting fine-grained spatial heterogeneity in warming and potential refugia for vegetation. Glob Change Biol 15(3):656–667. https://doi.org/10.1111/j.1365-2486.2008.01762.x
Ashcroft MB, Gollan JR, Warton DI, Ramp D (2012) A novel approach to quantify and locate potential microrefugia using topoclimate, climate stability, and isolation from the matrix. Glob Change Biol 18(6):1866–1879. https://doi.org/10.1111/j.1365-2486.2012.02661.x
Ávila-Flores IJ, Hernández-Díaz JC, González- MS, Prieto-Ruíz JÁ, Wehenkel C (2016) Pinus engelmannii Carr. in Northwestern Mexico: a review. Pak J Bot 48(5):2159–2166
Azzalini A, Torelli N (2007) Clustering via nonparametric density estimation. Stat Comput 17:71–80. https://doi.org/10.1007/s11222-006-9010-y
Balantic C, Adams A, Gross S, Mazur R, Sawyer S, Tucker J, Vernon M et al (2021) Toward climate change refugia conservation at an ecoregion scale. Conserv Sci Pract 3(9):e497. https://doi.org/10.1111/csp2.497
Barrows CW, Ramirez AR, Sweet LC, Morelli TL, Millar CI, Frakes N, Rodgers J, Mahalovich MF (2020) Validating climate-change refugia: empirical bottom-up approaches to support management actions. Front Ecol Environ 18(5):298–306. https://doi.org/10.1002/fee.2205
Barton AM (1993) Factors controlling plant distributions: drought, competition, and fire in montane pines in Arizona. Ecol Monogr 63(4):367–397. https://doi.org/10.2307/2937151
Barton AM, Poulos HM (2018) Pine vs. oaks revisited: conversion of Madrean pine-oak forest to oak shrubland after high-severity wildfire in the sky islands of Arizona. For Ecol Manage 414:28–40. https://doi.org/10.1016/j.foreco.2018.02.011
Barton AM, Swetnam TW, Baisan CH (2001) Arizona pine (Pinus arizonica) stand dynamics: local and regional factors in a fire-prone madrean gallery forest of Southeast Arizona, USA. Landsc Ecol 16(4):351–369. https://doi.org/10.1023/A:1011189408651
Boyko H (1947) On the role of plants as quantitative climate indicators and the geo-ecological law of distribution. J Ecol 35(1/2):138–157. https://doi.org/10.2307/2256504
Bucholz ER, Waring KM, Kolb TE, Swenson JK, Whipple AV (2020) Water relations and drought response of Pinus strobiformis. Can J for Res 50(9):905–916. https://doi.org/10.1139/cjfr-2019-0423
Buermann W, Saatchi S, Smith TB, Zutta BR, Chaves JA, Milá B, Graham CH (2008) Predicting species distributions across the Amazonian and Andean regions using remote sensing data. J Biogeogr 35(7):1160–1176. https://doi.org/10.1111/j.1365-2699.2007.01858.x
Coblentz DD, Riitters KH (2004) Topographic controls on the regional-scale biodiversity of the south-western United States. J Biogeogr 31(7):1125–1138. https://doi.org/10.1111/j.1365-2699.2004.00981.x
Conrad O, Bechtel B, Bock M, Dietrich H, Fischer E, Gerlitz L, Wehberg J, Wichmann V, Böhner J (2015) System for automated geoscientific analyses (SAGA) v. 2.1.4. Geosci Model Dev 8:1991–2007. https://doi.org/10.5194/gmd-8-1991-2015
Conservation International (2020) Biodiversity hotspots: Madrean pine-oak woodlands. https://www.cepf.net/our-work/biodiversity-hotspots/madrean-pine-oak-woodlands. Accessed 28 Mar 2022
Copenhaver-Parry PE, Shuman BN, Tinker DB (2017) Toward an improved conceptual understanding of North American tree species distributions. Ecosphere 8(6):e01853. https://doi.org/10.1002/ecs2.1853
Cord AF, Klein D, Gernandt DS, de la Rosa JAP, Dech S (2014) Remote sensing data can improve predictions of species richness by stacked species distribution models: a case study for Mexican pines. J Biogeogr 41(4):736–748. https://doi.org/10.1111/jbi.12225
Crimmins SM, Dobrowski SZ, Greenberg JA, Abatzoglou JT, Mynsberge AR (2011) Changes in climatic water balance drive downhill shifts in plant species optimum elevations. Science 331(6015):324–327. https://doi.org/10.1126/science.1199040
Deyo NS, Van Devender TR, Smith A, Gilbert E (2013) Documenting the biodiversity of the Madrean Archipelago: an analysis of a virtual flora and fauna. In: Gottfried GJ, Ffolliott PF, Gebow, Brooke S, Eskew LG, Collins LC (eds) Proeedings. RMRS-P-67. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, CO, pp 292–299
Dobrowski SZ (2011) A climatic basis for microrefugia: the influence of terrain on climate. Glob Change Biol 17(2):1022–1035. https://doi.org/10.1111/j.1365-2486.2010.02263.x
Elith J, Leathwick JR, Hastie T (2008) A working guide to boosted regression trees. J Anim Ecol 77(4):802–813
Farr TG, Rosen PA, Caro E, Crippen R, Duren R, Hensley S, Kobrick M, Paller M, Rodriguez E, Roth L, Seal D et al (2007) The shuttle radar topography mission. Rev Geophys. https://doi.org/10.1029/2005RG000183
Felger RS, Johnson MB, Wilson MF (2001) The trees of Sonora. Oxford University Press, New York
Ferguson GM, Flesch AD, Van Devender TR (2013) Biogeography and diversity of pines in the Madrean Archipelago. In: Gottfried GJ, Ffolliott PF, Gebow, Brooke S, Eskew LG, Collins LC (eds) Proceedings. RMRS-P-67. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, CO, pp 197–203
Findley JS (1996) Mammalian biogeography in the American Southwest. In: Genoways HH, Baker RJ (eds) Festschrift for J. Knox Jones, Jr., Texas Tech University Press, Lubbock, Texas, pp 297–308
Flesch AD (2019) Patterns and drivers of long‐term changes in breeding bird communities in a global biodiversity hotspot in Mexico. Divers Distrib 25(4):499–513. https://doi.org/10.1111/ddi.12862
Flesch AD, Gonzalez Sanchez C, Valenzuela Amarillas J (2016) Abundance and habitat relationships of breeding birds in the sky islands and adjacent Sierra Madre Occidental of northwest Mexico. J Field Ornithol 87:176–195. https://doi.org/10.1111/jofo.1215
Gamon JA, Field CB, Goulden ML, Griffin KL, Hartley AE, Joel G, Penuelas J, Valentini R (1995) Relationships between NDVI, canopy structure, and photosynthesis in three Californian vegetation types. Ecol Appl 5:28–41. https://doi.org/10.2307/1942049
Ganey JL, Block WM, Boucher PF (1996) Effects of fire on birds in Madrean forests and woodlands. In: Ffolliott PF, DeBano LF, Baker MB (tech coords). Gen. Tech. Rep. RM-GTR-289. U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. Fort Collins, CO, pp 146–154
Gao BC (1996) NDWI—a normalized difference water index for remote sensing of vegetation liquid water from space. Remote Sens Environ 58(3):257–266
Gómez-Mendoza L, Arriaga L (2007) Modeling the effect of climate change on the distribution of oak and pine species of Mexico. Conserv Biol 21(6):1545–1555. https://doi.org/10.1111/j.1523-1739.2007.00814
González-Cásares M, Pompa-García M, Camarero JJ (2017) Differences in climate–growth relationship indicate diverse drought tolerances among five pine species coexisting in Northwestern Mexico. Trees—Struct Funct 31(2):531–544. https://doi.org/10.1007/s00468-016-1488-0
González-Elizondo MS, González-Elizondo M, Tena-Flores JA, Ruacho-Gonzalez L, Lopez-Enriquez IL (2012) Vegetation of the Sierra Madre Occidental, Mexico: a synthesis. Acta Bot Mex 100:351–404
Gorelick N, Hancher M, Dixon M, Ilyushchenko S, Thau D, Moore R (2017) Google earth engine: planetary-scale geospatial analysis for everyone. Remote Sens Environ 202:18–27. https://doi.org/10.1016/j.rse.2017.06.031
Guillera-Arroita G, Lahoz-Monfort JJ, Elith J, Gordon A, Kujala H, Lentini PE, McCarthy MA, Tingley R, Wintle BA (2015) Is my species distribution model fit for purpose? Matching data and models to applications. Glob Ecol Biogeogr 24(3):276–292. https://doi.org/10.1111/geb.12268
Guisan A, Thuiller W (2005) Predicting species distribution: offering more than simple habitat models. Ecol Lett 8(9):993–1009. https://doi.org/10.1111/j.1461-0248.2005.00792.x
Haire SL, Villarreal ML (2022) Pine species distribution maps of the Madrean Sky Islands, U.S. Geological Survey data release, United States and México, https://doi.org/10.5066/P9CLBAF7
Haire SL, Coop JD, Miller C (2017) Characterizing spatial neighborhoods of refugia following large fires in northern New Mexico USA. Land. https://doi.org/10.3390/land6010019
Hampe A, Jump A (2011) Climate relicts: past, present, future. Annu Rev Ecol Evol Syst 42:313–333. https://doi.org/10.1146/annurev-ecolsys-102710-145015
Hampe A, Petit RJ (2005) Conserving biodiversity under climate change: the rear edge matters. Ecol Lett 8(5):461–467. https://doi.org/10.1111/j.1461-0248.2005.00739.x
Harrison S, Noss R (2017) Endemism hotspots are linked to stable climatic refugia. Ann Bot 119(2):207–214. https://doi.org/10.1093/aob/mcw248
He K, Jiang X (2014) Sky Islands of Southwest China. I: An overview of phylogeographic patterns. Chin Sci Bull 59(7):585–597. https://doi.org/10.1007/s11434-013-0089-1
Hess VA, Fulé PZ (2020) Is a Mexican pine species better adapted to the warming climate of the Southwestern USA? Front for Glob Change 3:60
Hoylman ZH, Jencso KG, Hu J, Holden ZA, Allred B, Dobrowski S, Robinson N, Martin JT, Affleck D, Seielstad C (2019) The topographic signature of ecosystem climate sensitivity in the western United States. Geophys Res Lett 46(24):14508–14520. https://doi.org/10.1029/2019GL085546
Iniguez JM, Swetnam TW, Yool S (2008) Topography affected landscape fire history patterns in southern Arizona, USA. For Ecol Manage 256:295–303
Iniguez JM, Swetnam TW, Baisan CH (2016) Fire history and moisture influences on historical forest age structure in the sky islands of southern Arizona, USA. J Biogeogr 43(1):85–95. https://doi.org/10.1111/jbi.12626
Jiménez-Valverde A (2012) Insights into the area under the receiver operating characteristic curve (AUC) as a discrimination measure in species distribution modelling. Glob Ecol Biogeogr 21(4):498–507. https://doi.org/10.1111/j.1466-8238.2011.00683.x
Keppel G, Wardell-Johnson GW (2015) Refugial capacity defines holdouts, microrefugia and stepping-stones: a response to Hannah et al. Trends Ecol Evol 30(5):233–234. https://doi.org/10.1016/j.tree.2015.01.008
Keppel G, Van Niel KP, Wardell-Johnson GW, Yates CJ, Byrne M, Mucina L, Schut AG, Hopper SD, Franklin SE (2012) Refugia: identifying and understanding safe havens for biodiversity under climate change. Glob Ecol Biogeogr 21(4):393–404. https://doi.org/10.1111/j.1466-8238.2011.00686.x
Keppel G, Ottaviani G, Harrison S, Wardell-Johnson GW, Marcantonio M, Mucina L (2018) Towards an eco-evolutionary understanding of endemism hotspots and refugia. Ann Bot. https://doi.org/10.1093/aob/mcy173
Krawchuk MA, Haire SL, Coop J, Parisien M-A, Whitman E, Chong G, Miller C (2016) Topographic and fire weather controls of fire refugia in forested ecosystems of northwestern North America. Ecosphere. https://doi.org/10.1002/ecs2.1632
Krawchuk MA, Meigs GW, Cartwright JM, Coop JD, Davis R, Holz A, Kolden C, Meddens AJH (2020) Disturbance refugia within mosaics of forest fire, drought, and insect outbreaks. Front Ecol Environ 18(5):235–244
Landsberg JJ, Waring RH (1997) A generalized model of forest productivity using simplified concepts of radiation-use efficiency, carbon balance and partitioning. For Ecol Manage 95:209–228
Looney CE, Waring KM (2013) Pinus strobiformis (southwestern white pine) stand dynamics, regeneration, and disturbance ecology: a review. For Ecol Manage 287:90–102. https://doi.org/10.1016/j.foreco.2012.09.020
Mackey B, Berry S, Hugh S, Ferrier S, Harwood TD, Williams KJ (2012) Ecosystem greenspots: identifying potential drought, fire, and climate-change micro-refuges. Ecol Appl 22(6):1852–1864
Mastretta-Yanes A, Xue AT, Moreno-Letelier A, Jorgensen TH, Alvarez N, Piñero D, Emerson BC (2018) Long-term in situ persistence of biodiversity in tropical Sky Islands revealed by landscape genomics. Mol Ecol 27(2):432–448. https://doi.org/10.1111/mec.14461
Mittermeier RA, Robles Gil P, Hoffman M, Pilgrim J, Brooks T, Mittermeier CG et al (2004) Hotspots revisited: earth’s biologically richest and most endangered ecoregions. CEMEX, Mexico City
Morelli TL, Daly C, Dobrowski SZ, Dulen DM, Ebersole JL, Jackson ST, Lundquist JD, Millar CI, Maher SP, Monahan WB, Nydick KR, Redmond KT, Sawyer SC, Stock S, Beissinger SR (2016) Managing climate change refugia for climate adaptation. PLoS ONE 11(8):1–17. https://doi.org/10.1371/journal.pone.0159909
Morelli TL, Barrows CW, Ramirez AR, Cartwright JM, Ackerly DD, Eaves TD, Ebersole JL, Krawchuk MA, Letcher BH, Mahalovich MF, Meigs GW et al (2020) Climate-change refugia: biodiversity in the slow lane. Front Ecol Environ 18(5):228–234. https://doi.org/10.1002/fee.2189
Myers N, Mittermeler RA, Mittermeler CG, Da Fonseca GAB, Kent J (2000) Biodiversity hotspots for conservation priorities. Nature 403(6772):853–858. https://doi.org/10.1038/35002501
Nelson TA, Boots B (2008) Detecting spatial hot spots in landscape ecology. Ecography 31(5):556–566. https://doi.org/10.1111/j.0906-7590.2008.05548.x
Nogué S, Rull V, Vegas-Vilarrúbia T (2013) Elevational gradients in the neotropical table mountains: patterns of endemism and implications for conservation. Divers Distrib 19(7):676–687. https://doi.org/10.1111/ddi.12017
Norman LM (2020) Ecosystem services of riparian restoration: a review of rock detention structures in the Madrean Archipelago Ecoregion. Air Soil Water Res. https://doi.org/10.1177/1178622120946337
Omernik JM (1987) Ecoregions of the conterminous United States. Ann Assoc Am Geogr 77(1):118–125. https://doi.org/10.1111/j.1467-8306.1987.tb00149.x
Pecl GT, Araújo MB, Bell JD, Blanchard J, Bonebrake TC, Chen IC, Clark TD, Colwell RK, Danielsen F, Evengård B, Falconi L et al (2017) Biodiversity redistribution under climate change: Impacts on ecosystems and human well-being. Science 355(6332):eaai9214. https://doi.org/10.1126/science.aai9214
Pezzoli K, Kozo J, Ferran K, Wooten W, Gomez GR, Al-Delaimy WK (2014) One bioregion/one health: an integrative narrative for transboundary planning along the United States-Mexico border. Glob Soc 28(4):419–440. https://doi.org/10.1080/13600826.2014.951316
Poulos HM, Barton AM, Berlyn GP, Schwilk DW, Faires CE, McCurdy WC (2020) Differences in leaf physiology among juvenile pines and oaks following high-severity wildfire in an Arizona Sky Island Mountain range. For Ecol Manage 457:117704. https://doi.org/10.1016/j.foreco.2019.117704
R Core Team (2021) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. https://www.R-project.org/Accessed 28 Mar 2022
Rehfeldt GE, Crookston NL, Sáenz-Romero C, Campbell EM (2012) North American vegetation model for land-use planning in a changing climate: a solution to large classification problems. Ecol Appl 22(1):119–141. https://doi.org/10.1890/11-0495.1
Rodríguez- DA, Fulé PZ (2003) Fire ecology of Mexican pines and a fire management proposal. Int J Wildland Fire 12(1):23–37. https://doi.org/10.1071/WF02040
Romme WH, Everham EH, Frelich LE, Moritz MA, Sparks RE (1998) Are large, infrequent disturbances qualitatively different from small, frequent disturbances? Ecosystems 1(6):524–534. https://doi.org/10.1007/s100219900048
Safont E, Vegas-Vilarrubia T, Rull V, Holst BK, Huber O, Nozawa S, Vivas Y, Font X, Silva A (2016) Plant communities and environmental factors in the Guayana Highlands: monitoring for conservation under future climate change. Syst Biodivers 14(4):327–344. https://doi.org/10.1080/14772000.2015.1134700
Sanderlin JS, Block WM, Ganey JL, Iniguez JM (2013) Preliminary assessment of species richness and avian community dynamics in the Madrean sky islands, Arizona. Merging science and management in a rapidly changing world: biodiversity and management of the Madrean Archipelago III. Proceedings. RMRS-P-67, pp 180–190.
Sanderlin JS, Block WM, Ganey JL, Iniguez JM, Cushman S (2014) Assessing large-scale effects of wildfire and climate change on avian communities and habitats in the sky islands, Arizona. Final report for U.S. Fish & Wildlife’s Desert Landscape Conservation Cooperative. https://www.sciencebase.gov/catalog/item/59b17f6fe4b020cdf7d9577b. Accessed 28 Mar 2022
Scherrer D, Körner C (2011) Topographically controlled thermal-habitat differentiation buffers alpine plant diversity against climate warming. J Biogeogr 38:406–416
Serra-Diaz JM, Scheller RM, Syphard AD, Franklin J (2015) Disturbance and climate microrefugia mediate tree range shifts during climate change. Landsc Ecol 30(6):1039–1053. https://doi.org/10.1007/s10980-015-0173-9
Sheppard PR, Comrie AC, Packin GD, Angersbach K, Hughes MK (2002) The climate of the US southwest. Clim Res 21:219–238. https://doi.org/10.3354/cr021219
Shirk AJ, Cushman SA, Waring KM, Wehenkel CA, Leal-Sáenz A, Toney C, Lopez-Sanchez CA (2018) Southwestern white pine (Pinus strobiformis) species distribution models project a large range shift and contraction due to regional climatic changes. For Ecol Manage 411:176–186. https://doi.org/10.1016/j.foreco.2018.01.025
Simons-Legaard E, D’Amato AW, Legaard K, Sturtevant B, Weiskittel A (2013) Future distribution and productivity of spruce-fir forests under climate change: a comparison of the Northeast and the Lake States. Northeastern States Research Cooperative final report. https://nsrcforest.org/project/future-distribution-and-productivity-spruce-fir-under-climate-change. Accessed 28 Mar 2022
Slaton M (2015) The roles of disturbance, topography and climate in determining the leading and rear edges of population range limits. J Biogeogr 42(2):255–266. https://doi.org/10.1111/jbi.12406
Spector S (2002) Biogeographic crossroads: priority areas for conservation. Conserv Biol 16(6):1480–1487
Travers-Smith HZ, Lantz TC (2020) Leading‐edge disequilibrium in alder and spruce populations across the forest–tundra ecotone. Ecosphere 11(7). https://doi.org/10.1002/ecs2.3118
Vegas-Vilarrúbia T, Nogué S, Rull V (2012) Global warming, habitat shifts and potential refugia for biodiversity conservation in the neotropical Guayana Highlands. Biol Conserv 152:159–168. https://doi.org/10.1016/j.biocon.2012.03.036
Villarreal ML, van Riper III C, Petrakis RE (2014) Conflation and aggregation of spatial data improve predictive models for species with limited habitats: a case of the threatened yellow-billed cuckoo in Arizona, USA. Appl Geogr 47:57–69. https://doi.org/10.1016/j.apgeog.2013.12.003
Villarreal ML, Haire SL, Bravo JC, Norman LM (2019) A mosaic of land tenure and ownership creates challenges and opportunities for transboundary conservation in the United States-Mexico borderlands. Case Stud Environ 3(1):1–10. https://doi.org/10.1525/cse.2019.002113
Villarreal ML, Iniguez JM, Flesch AD, Sanderlin JS, Montaño CC, Conrad CR, Haire SL (2020) Contemporary fire regimes provide a critical perspective on restoration needs in the Mexico-U.S. borderlands. Air Soil Water Res 13:1–18. https://doi.org/10.1177/1178622120969191
Wang T, Hamann A, Spittlehouse D, Carroll C (2016) Locally downscaled and spatially customizable climate data for historical and future periods for North America. PLoS ONE 11(6):1–17. https://doi.org/10.1371/journal.pone.0156720
Warshall P (1995) The Madrean Sky Island Archipelago: a planetary overview. In: Biodiversity and management of the Madrean Archipelago: The sky islands of Southwestern United States and Northwestern Mexico. General technical report RM-GTR-264. Tucson, Arizona: U.S. Forest Service
Whittaker RH, Niering WA (1965) Vegetation of the Santa Catalina Mountains, Arizona: a gradient analysis of the south slope. Ecology 46(4):429–452
Yanahan AD, Moore W (2019) Impacts of 21st-century climate change on montane habitat in the Madrean Sky Island Archipelago. Divers Distrib 25:1625–1638. https://doi.org/10.1111/ddi.12965