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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Plant litter | 3/3 | https://en.wikipedia.org/wiki/Plant_litter | reference | science, encyclopedia | 2026-05-05T07:18:56.129896+00:00 | kb-cron |
== Non-terrestrial litterfall == Non-terrestrial litterfall follows a very different path. Litter is produced both inland by terrestrial plants and moved to the coast by fluvial processes, and by mangrove ecosystems. From the coast Robertson & Daniel 1989 found it is then removed by the tide, crabs and microbes. They also noticed that which of those three is most significant depends on the tidal regime. Nordhaus et al. 2011 find crabs forage for leaves at low tide and if their detritivory is the predominant disposal route, they can take 80% of leaf material. Bakkar et al 2017 studied the chemical contribution of the resulting crab defecation. They find crabs pass a noticeable amount of undegraded lignins to both the sediments and water composition. They also find that the exact carbonaceous contribution of each plant species can be traced from the plant, through the crab, to its sediment or water disposition in this way. Crabs are usually the only significant macrofauna in this process, however Raw et al 2017 find Terebralia palustris competes with crabs unusually vigorously in southeast Asia.
== Collection and analysis == The main objectives of litterfall sampling and analysis are to quantify litterfall production and chemical composition over time in order to assess the variation in litterfall quantities, and hence its role in nutrient cycling across an environmental gradient of climate (moisture and temperature) and soil conditions. Ecologists employ a simple approach to the collection of litterfall, most of which centers around one piece of equipment, known as a litterbag. A litterbag is simply any type of container that can be set out in any given area for a specified amount of time to collect the plant litter that falls from the canopy above.
Litterbags are generally set in random locations within a given area and marked with GPS or local coordinates, and then monitored on a specific time interval. Once the samples have been collected, they are usually classified on type, size and species (if possible) and recorded on a spreadsheet. When measuring bulk litterfall for an area, ecologists will weigh the dry contents of the litterbag. By this method litterfall flux can be defined as:
litterfall (kg m−2 yr−1) = total litter mass (kg) / litterbag area (m2) The litterbag may also be used to study decomposition of the litter layer. By confining fresh litter in the mesh bags and placing them on the ground, an ecologist can monitor and collect the decay measurements of that litter. An exponential decay pattern has been produced by this type of experiment:
X
X
o
=
e
−
k
{\displaystyle {\frac {X}{X_{o}}}=e^{-k}}
, where
X
o
{\displaystyle X_{o}}
is the initial leaf litter and
k
{\displaystyle k}
is a constant fraction of detrital mass. The mass-balance approach is also utilized in these experiments and suggests that the decomposition for a given amount of time should equal the input of litterfall for that same amount of time.
litterfall = k(detrital mass) For study various groups from edaphic fauna you need a different mesh sizes in the litterbags
== Issues ==
=== Change due to invasive earthworms ===
In some regions of glaciated North America, earthworms have been introduced where they are not native. Non-native earthworms have led to environmental changes by accelerating the rate of decomposition of litter. These changes are being studied, but may have negative impacts on some inhabitants such as salamanders.
=== Forest litter raking === Leaf litter accumulation depends on factors like wind, decomposition rate and species composition of the forest. The quantity, depth and humidity of leaf litter varies in different habitats. The leaf litter found in primary forests is more abundant, deeper and holds more humidity than in secondary forests. This condition also allows for a more stable leaf litter quantity throughout the year. This thin, delicate layer of organic material can be easily affected by humans. For instance, forest litter raking as a replacement for straw in husbandry is an old non-timber practice in forest management that has been widespread in Europe since the seventeenth century. In 1853, an estimated 50 Tg of dry litter per year was raked in European forests, when the practice reached its peak. This human disturbance, if not combined with other degradation factors, could promote podzolisation; if managed properly (for example, by burying litter removed after its use in animal husbandry), even the repeated removal of forest biomass may not have negative effects on pedogenesis.
== See also == Coarse woody debris Detritus Forest floor Leaf litter sieve Leaf mold (a type of compost) Soil horizon
== References ==
== External links ==
forestresearch.gov.uk