ABSTRACT
Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world's five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems.
Subject(s)
Climate Change , Ecosystem , Forests , Trees/physiology , DroughtsABSTRACT
Sarcoptic mange is considered an emerging disease-causing countless epizootics and significantly affecting wild mammals worldwide. The vicuña (Vicugna vicugna) is a medium-sized South American wild camelid inhabiting Andean ecosystems, where several populations are live-sheared by Andean peasant communities as a way of providing an economic income to the people while promoting vicuña conservation. Institutions and scientists have shown concern for the impact and extent of sarcoptic mange in several vicuña populations across their range, as well as the lack of consistent knowledge about this disease in the species. Here, we perform a review about sarcoptic mange distribution throughout the vicuña's native range, evidence of effects of age and sex, the modes of transmission and the veterinary treatments employed. The review retrieved a few scientific papers, but found several reports and academic studies mostly considered as 'grey literature'. Mange was recorded across the entire native vicuña range (Argentina, Bolivia, Chile and Peru). Mange prevalence varied across vicuña studies (up to 60% prevalence in some populations) and severely affected a number of populations, being an important source of mortality. Mange was reported as more frequent in adults than in offspring. The modes of mange transmission remain unclear, although direct transmission between infected and healthy animals seems to be the most likely, including the transmission between domestic camelids and vicuñas. Regarding the treatments employed, ivermectin was the most frequently used. We further identified several gaps in knowledge and point to future research lines, which seek to promote both species conservation and the maintenance of live-shearing vicuñas under sustainable approaches in low-income Andean peasant communities.
