Editing Habitat fragmentation (section)

=== Implications ===
Forest fragmentation is one of the greatest threats to [[biodiversity]] in forests, especially in the tropics.<ref>{{cite book | last = Bierregaard | first = Richard | editor = Claude Gascon | editor2 = Thomas E. Lovejoy | editor3 = Rita Mesquita | year = 2001 | title = Lessons from Amazonia: The Ecology and Conservation of a Fragmented Forest | publisher = Yale University Press | isbn = 978-0-300-08483-2 | url-access = registration | url = https://archive.org/details/lessonsfromamazo0000unse}}</ref> The problem of [[habitat destruction]] that caused the fragmentation in the first place is compounded by:
* the inability of individual forest fragments to support viable populations, especially of large vertebrates
* the local [[extinction]] of species that do not have at least one fragment capable of supporting a viable population
* [[edge effect]]s that alter the conditions of the outer areas of the fragment, greatly reducing the amount of true forest interior habitat.<ref>{{cite book | last = Harris | first = Larry D. | year = 1984 | title = The Fragmented Forest: Island Biogeography Theory and the Preservation of Biotic Diversity | publisher = The University of Chicago Press | isbn = 978-0-226-31763-2 | url-access = registration | url = https://archive.org/details/fragmentedforest0000harr}}</ref>

The effect of fragmentation on the [[flora]] and [[fauna]] of a forest patch depends on a) the size of the patch, and b) its degree of isolation.<ref>{{Citation|last=Didham|first=Raphael K|chapter=Ecological Consequences of Habitat Fragmentation|date=2010-11-15|encyclopedia=Encyclopedia of Life Sciences|pages=a0021904|publisher=John Wiley & Sons|language=en|doi=10.1002/9780470015902.a0021904|isbn=978-0-470-01617-6}}</ref>  Isolation depends on the distance to the nearest similar patch, and the contrast with the surrounding areas. For example, if a cleared area is [[reforestation|reforested]] or allowed to [[natural regeneration|regenerate]], the increasing [[structural diversity]] of the [[vegetation]] will lessen the isolation of the forest fragments.  However, when formerly forested lands are converted permanently to pastures, agricultural fields, or human-inhabited developed areas, the remaining forest fragments, and the [[Biota (biology)|biota]] within them, are often highly isolated.

Forest patches that are smaller or more isolated will lose species faster than those that are larger or less isolated. A large number of small forest "islands" typically cannot support the same biodiversity that a single contiguous forest would hold, even if their combined area is much greater than the single forest. However, forest islands in rural landscapes greatly increase their biodiversity.<ref>{{Cite book |url=https://www.pemberleybooks.com/product/ecology-of-forest-islands/2679/ |title=Ecology of Forest Islands by , J. (ed.) |publisher=Bydgoszcz University Press |editor-last=Banaszak |editor-first=J.}}</ref> In the [[Maulino forest]] of Chile fragmentation appear to not affect overall plant diversity much, and tree diversity is indeed higher in fragments than in large continuous forests.<ref>{{cite book|last=Bustamante|first=Ramiro O.|author-last2=Simonetti|author-first2=Javier A.|author-last3=Grez|author-first3=Audrey A.|author-last4=San Martín|author-first4=José|date=2005|title=Historia, biodiversidad y ecología de los bosques costeros de Chile|chapter=Fragmentación y dinámica de regeneración del bosque Maulino: diagnóstico actual y perspectivas futuras|editor-last=Smith|editor-first=C.|editor-last2=Armesto|editor-first2=J.|editor-last3=Valdovinos|editor-first3=C.|chapter-url=http://bdrnap.mma.gob.cl/recursos/SINIA/Biblio_AP/070316BIBLIORNAP_164.pdf|pages=529–539|trans-chapter=Fragmentation and regeneration dynamics of the Maulino forest: present status and future prospects|language=es|access-date=2021-03-08|archive-date=2022-06-22|archive-url=https://web.archive.org/web/20220622150414/http://bdrnap.mma.gob.cl/recursos/SINIA/Biblio_AP/070316BIBLIORNAP_164.pdf|url-status=dead}}</ref><ref name=Bosque2020-3>{{Cite journal|title=Native and exotic plant species diversity in forest fragments and forestry plantations of a coastal landscape of central Chile|journal=[[Bosque (journal)|Bosque]]|url=https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0717-92002020000200125&lng=es&nrm=iso&tlng=en|last1=Becerra|first1=Pablo I.|volume=41|last2=Simonetti|first2=Javier A.|publisher=[[Austral University of Chile]]|issue=2|doi=10.4067/S0717-92002020000200125 |year=2020|pages=125–136|doi-access=free}}</ref>

[[McGill University]] in [[Montreal]], [[Quebec]], [[Canada]] released a university based newspaper statement stating that 70% of the world's remaining forest stands within one kilometre of a forest edge putting biodiversity at an immense risk based on research conducted by international scientists.<ref>{{Cite web|url=https://www.mcgill.ca/newsroom/channels/news/forest-fragmentation-threatens-biodiversity-243709|title=Forest fragmentation threatens biodiversity|website=Newsroom|language=en|access-date=2020-03-06}}</ref>

Reduced fragment area, increased isolation, and increased edge initiate changes that percolate through all ecosystems. Habitat fragmentation is able to formulate persistent outcomes which can also become unexpected such as an abundance of some species and the pattern that long temporal scales are required to discern many strong system responses.<ref name="Haddad2015" />