En La Senda De La Extinción: El Caso Del Algarrobo Prosopis Chilensis (Fabaceae) Y El Bosque Espinoso en La Región Metropolitana De Chile Central

Abstract

Además, la contracción poblacional de P. chilensis no se correlaciona con una expansión poblacional de A. caven, por lo cual las dos especies que definen y caracterizan el bosque espinoso de la Región Metropolitana de Chile se encuentran prontas a extinguirse y con ellas el piso vegetacional. Surge, por lo tanto, como necesidad urgente el establecer las medidas de conservación y restauración necesarias para asegurar la persistencia del bosque espinoso en la Región Metropolitana de Chile. PALABRAS CLAVE:Algarrobos, espinos, degradación ambiental, extirpaciones futuras. ABSTRACTAt central Chile grows the spiny forest of Acacia caven and Prosopis chilensis of which less than 40% of its original surface currently persists, but with no representation into the wilderness protected areas. Owing to the action of cattle, has it been previously suggested a population reduction of P. chilensis coupled to a population increase of A. caven which, nonetheless,has not yet verified empirically. At four sites belonging to two micro-basins in the Metropolitan Region at central Chile (Batuco and Huechún), we assessed the incidence of environmental disturbances (cattle, rabbits, weeds, garbage), the phytosanitary stage, and population structure of P. chilensis, as well as the regeneration dynamics of this tree and A. caven by using Markovian transition matrices. Populations of P. chilensis suffer similar degrees of threats, exhibit a similar but depauperate phytosanitary stage and, consequently, they face a senescent stage prone to disappear when the current adult individuals go death. Furthermore, the population decrease of P. chilensis does not correlate with the previously suggested population increase of A. caven; hence, the tree species characterizing and defining the spiny forest of central Chile are prone to be extinct and with them the vegetation belt. It appears, therefore, as an urgent necessity the establishment of conservation and restoration programs in order to assure the persistence of the spiny forest at the Metropolitan Region in central Chile.

Germination rates of four Chilean forest trees seeds: Quillaja saponaria, Prosopis chilensis, Vachellia caven, and Caesalpinia spinosa

“…Quillaja saponaria and Vachellia caven are two of the most representative trees in the Chilean Mediterranean forest ( Perez-Quezada & Bown, 2015 ), so information about these species will be useful for ecological investigation and restoration. Prosopis chilensis is vulnerable in the wild and is a key species of its community ( Valdivia & Romero, 2013 ); data about its propagation is important for conservation biologists.…”

Soil Microbiome Influences on Seedling Establishment and Growth of Prosopis chilensis and Prosopis tamarugo from Northern Chile

“…Soil properties and the soil microbiome have major effects on plant establishment, growth, and distribution [ 73 , 74 ]. In the Chilean deserts, Prosopis species stand out due to their high tolerance to harsh conditions, but their distributions are narrowing due to a lack of regeneration, with some species close to extinction [ 36 ]. Here, we studied the impact of soil properties and the soil microbiome on seedling establishment and growth of two Prosopis species, P. chilensis with a wide distribution and P. tamarugo , with a narrow distribution ( Figure S1 ), to understand the potential factors limiting the establishment of new seedlings in their natural environment.…”

“…Heavy usage of these species has reduced their historical distribution, leading to six of the species to be listed as vulnerable, endangered, or critically endangered ( Figure S1 ). The combination of climate change-induced increased desertification [ 6 ] and the current lack of recruitment of new seedlings [ 36 ] has increased the risk of local extinction of some Prosopis spp. [ 34 , 36 , 37 ].…”

“…The combination of climate change-induced increased desertification [ 6 ] and the current lack of recruitment of new seedlings [ 36 ] has increased the risk of local extinction of some Prosopis spp. [ 34 , 36 , 37 ].…”

Protocolo para la evaluación del riesgo de colapso de los ecosistemas: Caso de estudio del bosque espinoso (espinal) en la zona central de Chile

“…Por otra parte, el sobrepastoreo y la consecuente depredación de semillas y plántulas por animales como conejos y ganado, también han contribuido a la degradación y reestructuración del bosque espinoso (Fuentes et al 1989;Gutiérrez et al 2007). La presencia de escombros y basura en algunas áreas de su distribución, indican que las especies dominantes podrían enfrentar severas limitaciones en su reclutamiento, debido al daño mecánico que podrían experimentar las plántulas simplemente al verse aplastadas por este tipo de materiales (Valdivia & Romero 2013). Al mismo tiempo, los depósitos de basura han contaminado las aguas de las napas subterráneas, lo que dificulta aún más el posible reclutamiento y establecimiento de este tipo de árboles, ya que como habita en climas semiáridos, el agua es un recurso limitante (Gutiérrez et al 2007).…”