Editing Habitat fragmentation (section)

== Forest fragmentation ==
{{Split section|date=November 2022}}
{{Commons category|Forest fragmentation}}
Forest fragmentation is a form of habitat fragmentation where forests are reduced (either naturally or man-made) to relatively small, isolated patches of forest known as forest fragments or forest remnants.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates" /> The intervening matrix that separates the remaining woodland patches can be natural open areas, [[farmland]], or developed areas. Following the principles of [[island biogeography]], remnant woodlands act like islands of forest in a sea of pastures, fields, subdivisions, shopping malls, etc. These fragments will then begin to undergo the process of [[ecosystem decay]].

Forest fragmentation also includes less subtle forms of discontinuities such as utility right-of-ways (ROWs). Utility ROWs are of ecological interest because they have become pervasive in many forest communities, spanning areas as large as 5 million acres in the United States.<ref name="Russell2005">{{Cite journal|last1=Russell|first1=K. N.|last2=Ikerd|first2=H.|last3=Droege|first3=S.|date=2005-07-01|title=The potential conservation value of unmowed powerline strips for native bees|journal=Biological Conservation|volume=124|issue=1|pages=133–148|doi=10.1016/j.biocon.2005.01.022|bibcode=2005BCons.124..133R }}</ref> Utility ROWs include electricity transmission ROWs, gas pipeline and telecommunication ROWs. Electricity transmission ROWs are created to prevent vegetation interference with transmission lines. Some studies have shown that electricity transmission ROWs harbor more plant species than adjoining forest areas,<ref>{{Cite journal|last1=Wagner|first1=David L.|last2=Metzler|first2=Kenneth J.|last3=Leicht-Young|first3=Stacey A.|last4=Motzkin|first4=Glenn|date=2014-09-01|title=Vegetation composition along a New England transmission line corridor and its implications for other trophic levels|journal=Forest Ecology and Management|volume=327|pages=231–239|doi=10.1016/j.foreco.2014.04.026|bibcode=2014ForEM.327..231W }}</ref> due to alterations in the microclimate in and around the corridor. Discontinuities in forest areas associated with utility right-of-ways can serve as biodiversity havens for native bees <ref name="Russell2005" /> and grassland species,<ref>{{cite journal |last1=Lampinen |first1=Jussi |last2=Ruokolainen |first2=Kalle |last3=Huhta |first3=Ari-Pekka |last4=Chapman |first4=Maura (Gee) Geraldine |title=Urban Power Line Corridors as Novel Habitats for Grassland and Alien Plant Species in South-Western Finland |journal=PLOS ONE |date=13 November 2015 |volume=10 |issue=11 |pages=e0142236 |doi=10.1371/journal.pone.0142236 |pmid=26565700 |pmc=4643934 |bibcode=2015PLoSO..1042236L|doi-access=free }}</ref> as the right-of-ways are preserved in an early successional stage.

Forest fragmentation reduces food resources and [[habitat]] sources for animals thus splitting these species apart. Thus, making these animals become much more susceptible to effects of [[predation]] and making them less likely to perform [[Hybrid (biology)|interbreeding]] - lowering genetic diversity.<ref>{{Citation|last1=Bogaert|first1=Jan|title=Forest Fragmentation: Causes, Ecological Impacts and Implications for Landscape Management|date=2011|work=Landscape Ecology in Forest Management and Conservation: Challenges and Solutions for Global Change|pages=273–296|editor-last=Li|editor-first=Chao|publisher=Springer|language=en|doi=10.1007/978-3-642-12754-0_12|isbn=978-3-642-12754-0|last2=Barima|first2=Yao S. S.|last3=Mongo|first3=Léon Iyongo Waya|last4=Bamba|first4=Issouf|last5=Mama|first5=Adi|last6=Toyi|first6=Mireille|last7=Lafortezza|first7=Raffaele|editor2-last=Lafortezza|editor2-first=Raffaele|editor3-last=Chen|editor3-first=Jiquan}}</ref>

Additionally, forest fragmentation affects the native plant species present within the area by dividing large populations into smaller ones. In turn, smaller populations are more inclined to be affected by genetic drift and population performance, as well as experience increases in inbreeding activities.<ref name=":0">{{Cite journal |last1=Leimu |first1=Roosa |last2=Vergeer |first2=Philippine |last3=Angeloni |first3=Francesco |last4=Ouborg |first4=N. Joop |date=May 2010 |title=Habitat fragmentation, climate change, and inbreeding in plants |url=https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.2010.05450.x |journal=Annals of the New York Academy of Sciences |language=en |volume=1195 |issue=1 |pages=84–98 |doi=10.1111/j.1749-6632.2010.05450.x |pmid=20536818 |bibcode=2010NYASA1195...84L |issn=0077-8923|url-access=subscription }}</ref> Moreover, fragmentation can affect the relationship present between animals and plants, such as the relationships regarding seed-dispersal or pollinator-plant relationship.<ref name=":0" /><ref>{{Cite journal |last1=Xiao |first1=Yian |last2=Li |first2=Xiaohong |last3=Cao |first3=Yusong |last4=Dong |first4=Ming |date=2016-07-01 |title=The diverse effects of habitat fragmentation on plant–pollinator interactions |url=https://doi.org/10.1007/s11258-016-0608-7 |journal=Plant Ecology |language=en |volume=217 |issue=7 |pages=857–868 |doi=10.1007/s11258-016-0608-7 |bibcode=2016PlEco.217..857X |issn=1573-5052|url-access=subscription }}</ref>

=== 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" />

=== Sustainable forest management ===

The presence of forest fragments influences the supply of various [[ecosystem]]s in adjacent [[Agriculture|agricultural]] fields (Mitchell et al. 2014). Mitchell et al. (2014), researched on six varying ecosystem factors such as crop production, [[decomposition]], [[pesticide regulation]], carbon storage, [[soil fertility]], and water quality regulation in soybean fields through separate distances by nearby forest fragments which all varied in isolation and size across an agricultural landscape in [[Quebec|Quebec, Canada]]. Sustainable forest management can be achieved in several ways including by managing forests for [[ecosystem service]]s (beyond simple provisioning), through government compensation schemes, and through effective regulation and legal frameworks.<ref>{{Citation|title=Chapter 23 - Sustainable Forest Management|date=2019-01-01|url=https://repozitorij.uni-lj.si/IzpisGradiva.php?id=36180|journal=Sustainable Food and Agriculture|pages=233–236|editor-last=Campanhola|editor-first=Clayton|publisher=Academic Press|doi=10.1016/B978-0-12-812134-4.00023-6|language=en|isbn=978-0-12-812134-4|s2cid=128938268|editor2-last=Pandey|editor2-first=Shivaji|url-access=subscription}}</ref> The only realistic method of conserving forests is to apply and practice sustainable [[forest management]] to risk further loss.

There is a high industrial demand for [[wood]], [[Pulp (paper)|pulp]], [[paper]], and other resources which the [[forest]] can provide with, thus businesses which will want more access to the cutting of forests to gain those resources. The [[Rainforest Alliance|rainforest alliance]] has efficiently been able to put into place an approach to sustainable forest management, and they established this in the late 1980s. Their [[Conservation biology|conservation]] was deemed successful as it has saved over nearly half a billion acres of land around the world.<ref name="What is Sustainable Forestry">{{Cite web|url=https://www.rainforest-alliance.org/articles/what-is-sustainable-forestry|title=What is Sustainable Forestry?|website=Rainforest Alliance|date=28 July 2016|language=en|access-date=2020-03-06}}</ref>

A few approaches and measures which can be taken in order to conserve forests are methods by which erosion can be minimized, waste is properly disposed, conserve native [[tree]] species to maintain [[genetic diversity]], and setting aside forestland (provides habitat for critical [[Species|wildlife species]]).<ref name="What is Sustainable Forestry" /> Additionally, [[Wildfire|forest fires]] can also occur frequently and measures can also be taken to further prevent forest fires from occurring. For example, in [[Guatemala]]’s culturally and ecologically significant [[Petén Department|Petén]] region, researchers were able to find over a 20-year period, actively managed [[Forest Stewardship Council|FSC]]-certified forests experienced substantially lower rates of [[deforestation]] than nearby protected areas, and forest fires only affected 0.1 percent of certified land area, compared to 10.4 percent of protected areas.<ref name="What is Sustainable Forestry" /> However, it must be duly noted that short term decisions regarding forest sector employment and harvest practices can have long-term effects on biodiversity.<ref>{{Cite web|url=https://www.fs.fed.us/nrs/pubs/gtr/gtr_nrs90/gtr-nrs-90-chapter-4.pdf|title=Strategies for Sustainable Forest Management|website=fed.us}}</ref> Planted forests become increasingly important as they supply approximately a quarter of global industrial roundwood production and are predicted to account for 50% of global output within two decades (Brown, 1998; Jaakko Poyry, 1999).<ref>{{Cite journal|last1=Siry|first1=Jacek P.|last2=Cubbage|first2=Frederick W.|last3=Ahmed|first3=Miyan Rukunuddin|date=2005-05-01|title=Sustainable forest management: global trends and opportunities|journal=Forest Policy and Economics|language=en|volume=7|issue=4|pages=551–561|doi=10.1016/j.forpol.2003.09.003|bibcode=2005ForPE...7..551S |issn=1389-9341}}</ref> Although there have been many difficulties, the implementation of forest certification has been quite prominent in being able to raise effective awareness and disseminating knowledge on a holistic concept, embracing economic, environmental and social issues, worldwide. While also providing a tool for a range of other applications than assessment of [[sustainability]], such as e.g. verifying [[Carbon sink|carbon sinks.]]<ref>{{Cite journal|last1=Rametsteiner|first1=Ewald|last2=Simula|first2=Markku|date=2003-01-01|title=Forest certification—an instrument to promote sustainable forest management?|journal=Journal of Environmental Management|series=Maintaining Forest Biodiversity|language=en|volume=67|issue=1|pages=87–98|doi=10.1016/S0301-4797(02)00191-3|pmid=12659807|bibcode=2003JEnvM..67...87R |issn=0301-4797}}</ref>