Editing Chaparral (section)

=== Invasive species effects on soil composition post and pre fire ===
Invasive species impact the chaparral ecosystem in many ways; they inhibit the re-establishment of native species, promote shorter term fire frequency, and change chemical composition of soils which ultimately impedes native species success. Annual Invasion on chaparral environments leads to lower levels of readily available Nitrogen (N) for native plants, affects the [[Carbon-to-nitrogen ratio|Carbon-to-Nitrogen]] ratio (C/N), develops shallow fine root systems, creates more litter and aboveground biomass and can increase soil respiration. Native plants rely on nitrogen to grow so when non natives invade they take this away hindering plant growth. High frequency fire due to invasive grasses increase the amount of Nitrogen lost due to volatilization, as nitrogen is lost more consistently native shrubs struggle due to lower then normal nitrogen levels.<ref>{{Cite journal |last=Debano |first=L. F. |last2=Conrad |first2=C. E. |date=May 1978 |title=The Effect of Fire on Nutrients in a Chaparral Ecosystem |url=http://doi.wiley.com/10.2307/1936579 |journal=Ecology |language=en |volume=59 |issue=3 |pages=489–497 |doi=10.2307/1936579}}</ref> Non-Native invasive such as grasses tend to have shallower root systems that outcompete natives such as [[Manzanita|M''anzanita'']]'', [[Adenostoma fasciculatum|Chamise]]'' and ''[[Ceanothus]]''. Since invasive grasses root systems are much shallower they reduce soil moisture at the top level of the soil, this greatly reduces the prosperity of re establishing native seedlings.<ref>{{Cite journal |last=Phillips |first=Michala L. |last2=Allen |first2=Edith B. |date=March 2024 |title=Invasive grass density negatively impacts chaparral seedling establishment |url=https://onlinelibrary.wiley.com/doi/10.1111/rec.14053 |journal=Restoration Ecology |language=en |volume=32 |issue=3 |doi=10.1111/rec.14053 |issn=1061-2971}}</ref> Increased plant litter and biomass aboveground crowd out natives and change desirable soil compositions.<ref>{{Cite journal |last=Zedler |first=Paul H. |last2=Gautier |first2=Clayton R. |last3=McMaster |first3=Gregory S. |date=August 1983 |title=Vegetation Change in Response to Extreme Events: The Effect of a Short Interval between Fires in California Chaparral and Coastal Scrub |url=https://esajournals.onlinelibrary.wiley.com/doi/10.2307/1937204 |journal=Ecology |language=en |volume=64 |issue=4 |pages=809–818 |doi=10.2307/1937204 |issn=0012-9658}}</ref>

[[Plant litter]] when decomposed brings vital nutrients such as Carbon into the below soil. Invasive grasses produce litter with less recalcitrant Carbon in turn resulting in less Carbon intrusion. Recalcitrant carbon is found in higher quantities and quality in native shrubs litter, recalcitrant carbon takes longer to break down and is resistant to decomposing so it can stay in the soil for centuries. Chaparral provides vital [[Carbon sink|carbon sinks]] for our environment, when invasive grasses move in after short frequency fires we see less carbon storage and more carbon set free into the atmosphere.<ref name=":1">{{Cite journal |last=Dickens |first=S. J. M. |last2=Allen |first2=E. B. |date=May 2014 |title=Exotic plant invasion alters chaparral ecosystem resistance and resilience pre- and post-wildfire |url=http://link.springer.com/10.1007/s10530-013-0566-0 |journal=Biological Invasions |language=en |volume=16 |issue=5 |pages=1119–1130 |doi=10.1007/s10530-013-0566-0 |issn=1387-3547}}</ref>

To combat these non-native invasions and potentially balance degraded soils, techniques such as weeding and seeding along with [[Hydroseeding|hydro seeding]] can prove effective. Weeding and re seeding native species takes away competition after disturbances and allows native species to increase density.<ref name=":1" /> Post fire Carbon and Nitrogen levels greatly decrease and hydro seeding can help bring these levels back to what they were pre fire.<ref>{{Cite journal |last=Vourlitis |first=George |last2=Steinecke |first2=Dylan |last3=Martinez |first3=Tanairi |last4=Konda |first4=Karen |last5=Rendon |first5=Roxana |last6=Hall |first6=Victoria |last7=Khor |first7=Sherryca |last8=Sethuraman |first8=Arun |date=March 2022 |title=Fire and post-fire management alters soil microbial abundance and activity: A case study in semi-arid shrubland soils |url=https://linkinghub.elsevier.com/retrieve/pii/S092913932100442X |journal=Applied Soil Ecology |language=en |volume=171 |pages=104319 |doi=10.1016/j.apsoil.2021.104319|doi-access=free }}</ref> Although hydro seeding can help balance these levels it is important to note that hydro seeding does open up the possibility of introducing invasive species and has potential long lasting effects on Carbon and Nitrogen cycles in chaparral ecosystems.