North American vegetation model for land‐use planning in a changing climate: a solution to large classification problems

Abstract

Data points intensively sampling 46 North American biomes were used to predict the geographic distribution of biomes from climate variables using the Random Forests classification tree. Techniques were incorporated to accommodate a large number of classes and to predict the future occurrence of climates beyond the contemporary climatic range of the biomes. Errors of prediction from the statistical model averaged 3.7%, but for individual biomes, ranged from 0% to 21.5%. In validating the ability of the model to identify climates without analogs, 78% of 1528 locations outside North America and 81% of land area of the Caribbean Islands were predicted to have no analogs among the 46 biomes. Biome climates were projected into the future according to low and high greenhouse gas emission scenarios of three General Circulation Models for three periods, the decades surrounding 2030, 2060, and 2090. Prominent in the projections were (1) expansion of climates suitable for the tropical dry deciduous forests of Mexico, (2) expansion of climates typifying desertscrub biomes of western USA and northern Mexico, (3) stability of climates typifying the evergreen-deciduous forests of eastern USA, and (4) northward expansion of climates suited to temperate forests, Great Plains grasslands, and montane forests to the detriment of taiga and tundra climates. Maps indicating either poor agreement among projections or climates without contemporary analogs identify geographic areas where land management programs would be most equivocal. Concentrating efforts and resources where projections are more certain can assure land managers a greater likelihood of success.

Pinus leiophylla suitable habitat for 1961-1990 and future climate

“…14,000 plots with species other than conifers. To assure that our sample of absence observations was representative of the vegetation of Mexico, we also used a systematic sampling of point locations within the digitized map of the Biotic Communities of North America (Brown et al, 1998;Rehfeldt et al, 2012). Technical procedures, described in detail in Rehfeldt et al (2006) and used also by Ledig et al (2010) involved the use of ARCMAP software to procure a systematic sample of point locations from each polygon on the map and assign an elevation to each point from the digitized elevation model of GLOBE Task Team (1999).…”

“…Technical procedures, described in detail in Rehfeldt et al (2006) and used also by Ledig et al (2010) involved the use of ARCMAP software to procure a systematic sample of point locations from each polygon on the map and assign an elevation to each point from the digitized elevation model of GLOBE Task Team (1999). Data points from all communities within which P. leiophylla can occur (Madrean Montane Conifer Forest, TransvolcanicGuatemalan Conifer Forests, and Madrean-Transvolcanic Pine-Oak Woodland, biomes as defi ned by Rehfeldt et al (2012), based on classifi cation by Brown et al (1998) were discarded in this step, and some biomes where there are no conifer tree species were explicitly included (Tamaulipan Thornscrub, Gulf Coastal Grassland, Savanna Grasslands, Western Alpine Tundra, California Valley Grassland, California Coastalscrub, Mohave Desertscrub, Pacifi c Coast Thornscrub, Sonoran Desertscrub, Great Basin Desertscrub, Chihuahuan Desertscrub, Semidesert Grassland, and Great Basin Shrub-Grassland). With this last step we aimed to include absence locations with clearly unfavorable conditions, similar of what suggested Chefaoui and Lobo (2008) or Jiménez-Valverde et al (2008) for obtaining most constrained predictive distribution maps; with the difference that our climatically distant absence sites are not pseudoabsences, because those absence sites were actually visited on the ground by personnel of the Forest Inventory and absences can be inferred without doubt.…”

La restauración ecológica clásica y los retos de la actualidad: La migración asistida como estrategia de adaptación al cambio climático

“…Esto puede ser un escenario plausible para las poblaciones de muchas especies arbóreas que se están desacoplando del clima al cual estaban adaptadas a causa del cambio climático (Sáenz-Romero, LindigCisneros, Joyce, Beaulieu, Bradley & Jaquish, 2016). En algunos años las condiciones climáticas donde habitan podrían darse en un lugar diferente o desaparecer (Rehfeldt, Crookston, Sáenz-Romero & Campbell, 2012). Pero en la actualidad deben tolerar la variabilidad climática en sus hábitats, lo cual puede causar un incremento de estrés fisiológico en las especies, volviéndolas …”

Migración asistida de las poblaciones forestales para la adaptación de árboles ante el cambio climático

“…As a consequence of climate change, models predict that suitable climatic habitats for most of the current North American biomes will either shift to more northerly latitudes, climb to higher elevations, expand (xeric biomes, such as dry deciduous forest), shrink (several temperate and high altitude biomes, such as alpine forest) or disappear (rare and humid biomes, such as cloud forest) (Aitken, Yeaman, Holliday, Wang, & Curtis-McLane, 2008;Rehfeldt, Crookston, Sáenz-Romero, & Campbell, 2012;Rehfeldt et al, 2014).…”

“…Como consecuencia del cambio climático, los modelos predicen que los hábitats climáticos apropiados para la mayoría de los biomas actuales de América del Norte se desplazarán a latitudes más al Norte, ascenderán a altitudes mayores, se expandirán (biomas xerófilos, como el bosque seco caducifolio), se contraerán (varios biomas templados y de gran altitud, como el bosque alpino) o desaparecerán (biomas raros y húmedos, como el bosque de niebla) (Aitken, Yeaman, Holliday, Wang, & Curtis-McLane, 2008;Rehfeldt, Crookston, Sáenz-Romero, & Campbell, 2012;Rehfeldt et al, 2014).…”