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reasonsforhope · 4 months

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Ancient redwoods recover from fire by sprouting 1000-year-old buds

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When lightning ignited fires around California’s Big Basin Redwoods State Park north of Santa Cruz in August 2020, the blaze spread quickly. Redwoods naturally resist burning, but this time flames shot through the canopies of 100-meter-tall trees, incinerating the needles. “It was shocking,” says Drew Peltier, a tree ecophysiologist at Northern Arizona University. “It really seemed like most of the trees were going to die.”

Yet many of them lived. In a paper published yesterday in Nature Plants, Peltier and his colleagues help explain why: The charred survivors, despite being defoliated [aka losing all their needles], mobilized long-held energy reserves—sugars that had been made from sunlight decades earlier—and poured them into buds that had been lying dormant under the bark for centuries.

“This is one of those papers that challenges our previous knowledge on tree growth,” says Adrian Rocha, an ecosystem ecologist at the University of Notre Dame. “It is amazing to learn that carbon taken up decades ago can be used to sustain its growth into the future.” The findings suggest redwoods have the tools to cope with catastrophic fires driven by climate change, Rocha says. Still, it’s unclear whether the trees could withstand the regular infernos that might occur under a warmer climate regime.

Mild fires strike coastal redwood forests about every decade. The giant trees resist burning thanks to the bark, up to about 30 centimeters thick at the base, which contains tannic acids that retard flames. Their branches and needles are normally beyond the reach of flames that consume vegetation on the ground. But the fire in 2020 was so intense that even the uppermost branches of many trees burned and their ability to photosynthesize went up in smoke along with their pine needles.

Trees photosynthesize to create sugars and other carbohydrates, which provide the energy they need to grow and repair tissue. Trees do store some of this energy, which they can call on during a drought or after a fire. Still, scientists weren’t sure these reserves would prove enough for the burned trees of Big Basin.

Visiting the forest a few months after the fire, Peltier and his colleagues found fresh growth emerging from blackened trunks. They knew that shorter lived trees can store sugars for several years. Because redwoods can live for more than 2000 years, the researchers wondered whether the trees were drawing on much older energy reserves to grow the sprouts.

Average age is only part of the story. The mix of carbohydrates also contained some carbon that was much older. The way trees store their sugar is like refueling a car, Peltier says. Most of the gasoline was added recently, but the tank never runs completely dry and so a few molecules from the very first fill-up remain. Based on the age and mass of the trees and their normal rate of photosynthesis, Peltier calculated that the redwoods were calling on carbohydrates photosynthesized nearly 6 decades ago—several hundred kilograms’ worth—to help the sprouts grow. “They allow these trees to be really fire-resilient because they have this big pool of old reserves to draw on,” Peltier says.

It's not just the energy reserves that are old. The sprouts were emerging from buds that began forming centuries ago. Redwoods and other tree species create budlike tissue that remains under the bark. Scientists can trace the paths of these buds, like a worm burrowing outward. In samples taken from a large redwood that had fallen after the fire, Peltier and colleagues found that many of the buds, some of which had sprouted, extended back as much as 1000 years. “That was really surprising for me,” Peltier says. “As far as I know, these are the oldest ones that have been documented.”

... “The fact that the reserves used are so old indicates that they took a long time to build up,” says Susan Trumbore, a radiocarbon expert at the Max Planck Institute for Biogeochemistry. “Redwoods are majestic organisms. One cannot help rooting for those resprouts to keep them alive in decades to come.”

-via Science, December 1, 2023

#redwoods #california #wildfire #climate change #extreme heat #natural disasters #botany #plant biology #photosynthesis #santa cruz #hopepunk #sustainability #climate hope #united states #good news #hope

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acklotol · 6 months

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what are you talking about of course theres a shark in the greenhouse

#botany #shark #silly #greenhouse #plants #plant #sharks #biology #plantblr #plant biology #marine biology

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katiajewelbox · 8 months

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“It is not so much for its beauty that the forest makes a claim upon men’s hearts, as for that subtle something, that quality of air that emanation from old trees, that so wonderfully changes and renews a weary spirit.”

― Robert Louis Stevenson

Source: Grow Your Garden Instagram page

#katia plant scientist #botany #plant biology #plant science #plants #trees #plants make people happy #sustainability #ecological #solarpunk #intersectional environmentalism #environmentalism

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intrinsically-disordered-proxein · 1 month

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#i didnt make this credit to my friend ubro for making the funniest shit alive #they gave me permission to post #ophioglossum reticulatum #biology #meme #botany #i think #ferns #plant biology #plant genetics #dude these guys are so fucked up #acamemeia

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cedar-glade · 6 months

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Swamp milkweed, Asclepias incarnata, growing in a marl mound with multiple rushes and sedges reminiscent of ancient river scours in Tennessee and glacial alvar wetlands. Most of the sedges are state listed in Ohio. A balled faced hornet with a few corpuscule (singular corpusculum) attached to the hooks on it's legs is seen getting nectar and pollinating. Its cool to check in on all of you Asclepias incarnata you come to in-situ. It tells you a lot about pollinators present. The other thing that makes this species interesting is further divisions. SSP. incarnata and pulchera respectively as of current are divided into two sections and appear to have a northern/ plains and eastern/ southern dist. The hairy stemmed pulchera(G5) is fairly variable and much more common with conduplicate foliage and dark purple flowers unlike above. The other accepted subsp. is considered G4 and is glaberous with a height reduction in many cases and smaller leaves on average. The real kicker is someone has reported glandular hair in the past and I am curious if a third ssp. even occurs or if it was a missed report.

#ohio #botany #plant biology #plantblr #ecology #asclepias #wildflowers #asclepias incarnata #green

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wildlifetracker · 10 months

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A few of my favorite unique fern species at my job

#ferns #fern #plants #botany #plant biology #biology #plant #mine #conservatory #plant conservatory #nature #nature photography #naturalist #photography #ecology #ecologist

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mosslovr · 2 years

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i love you moss i love you liverworts i love you hornworts i love you nonvascular plants i love you bryophytes

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heavenly-garden · 7 days

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Puya Alpestris aka The Sapphire Tower.

One of the most unique plants in the world.

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just-some-moss-and-bones · 6 months

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translocation is when I (a trans person) locate another trans person by vibes alone

I know bimonolojy

#biology #plant biology #science #trans meme

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i-should-have-studied · 11 days

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Mod 3: Gymnosperms

Pinus Needle T.S.

It is circular in outline in P. monophylla, semicircular in P. sylvestris and triangular in P. longifolia, P. roxburghii, etc.

Outermost layer is epidermis, which consists of thick-walled cells. It is covered by a very strong cuticle.

Many sunken stomata are present on the epidermis.

Each stomata opens internally into a substomatal cavity and externally into a respiratory cavity or vestibule.

Below the epidermis are present a few layers of thick-walled sclerenchymatous hypodermis. It is well developed at ridges

In between the hypodermis and endodermis is present the mesophyll tissue.

Cells of the mesophyll are polygonal and filled with chloroplasts. Many peg-like infoldings of cellulose also arise from the inner side of the wall of mesophyll cells.

Few resin canals are present in the mesophyll, adjoining the hypodermis. Their number is variable but generally they are two in number.

Endodermis is single-layered with barrel-shaped cells and clear casparian strips.

Pericycle is multilayered and consists of mainly parenchymatous cells and some sclerenchymatous cells forming T-shaped girder, which separates two vascular bundles. Transfusion tissue consists of tracheidial cells.

Two conjoint and collateral vascular bundles are present in the center. These are closed but cambium may also be present in the sections passing through the base of the needle.

Xylem lies towards the angular side and the phloem towards the convex side of the needle.

Idk where to find xeric nature info

Williamsoniaceae

Occurrence of Williamsonia

Williamsonia belongs to family Williamsoniaceae of Bennettiales.

It has been reported from Upper Triassic period but was more abundant in Jurassic.

This was earlier discovered under the name Zamia gigas by Willamson in 1870 but has now been named as Williamsonia.

Professor Birbal Sanhi (1932) described W. sewardiana from Rajmahal Hills of Bihar (India).

External Features of Williamsonia

Williamsonia resembled Cycas in appearance, but its best-knows species is W. sewardiana. The plant had an upright, branched, and stout stem covered by persistent leaf bases.

A terminal crown of pinnately compound leaves was present. For the stem genus Bucklandia, Sharma (1991) opined that features of leaf bases such as their shape, size and arrangement pattern are of taxonomic significance.

He observed that leaves in Williamsoniaceae show syndetocheilic stomata with rachis possessing collateral endarch vascular bundles.

Reproduction in Williamsonia

The fructifications of Williamsonia were large and attained a diameter of about 12 cm.

They were borne on a peduncle.

Many spirally arranged bracts were present around the base of the floral axis.

In W. gigas the cones were present among the crown of leaf bases while in W. sewardinia they were present on the short lateral branches.

Williamsonia plants were unisexual.

Female Flower

The female 'cones' of W. gigas and W. sewardiana have been investigated in detail. Instead of 'strobili' or 'cones', Sporne (1965) proposed to use the term 'flower'.

The conical receptacle was surrounded by many perianth-like bracts. The ovules were stalked.

The apex of the receptacle was naked and sterile. The nucellus was surrounded by a single vascularize integument, which was fused with the nucellus. The nucellus had a well-marked beak and a pollen chamber. In young ovules the micropylar canal was long and narrow.

In mature ovules, the canal widened because of the formation of nucellar plug and disappearance of interlocking cells. In the apical part of the endosperm, Sharma (1979) observed 2 or more archegonia.

Male Flower

Male flowers consisted of a whorl of microsporophyll's which were united to form a more or less cuplike structure. In majority of the investigates species the sporophylls were un-branched but in some species they were also pinnately branched.

Sitholey and Bose discovered W. santalensis from Upper Gondwana, and observed that microsporophyll's in the species were bifid.

One of the branches of microsporophyll was fertile while the other was sterile. The fertile part has finger-like structures called synangia. Each synangium had two rows of chambers enclosing microsporangia.

The fertile branch of the bifid sporophyll possessed many purse-like capsules, in each of which there were present many monocolpate pollen grains.

Cycadeoideaceae

Classification:

Division - Cycadeoidophyta

Order - Cycadeoideales

Family - Cycadeoideaceae

Genus - Cycadeoidea

Introduction:

Cycadeoidea is the only genus of family Cycadeoidaceae, represented by thirty species. They are entirely extinct and resemble cycads in the outward stumpy appearance of trunk and an apical crown of pinnate compound leaves. This fossil group of plants flourished during the Triassic to Cretaceous periods of the Mesozoic era. They are reported from various places in the world, in India the Cycadeoidales are found in Rajmahal Hills in Bihar. The petrified trunks of C. entrusca are the oldest fossil ever collected by man.

External Features:

The genus Cycadeoidea had a short, branched, or unbranched spherical, conical, or irregular trunk. The diameter of the trunk is 50cm and the highest rarely reached a meter except in C. jenneyana, it attended the height of several meters. These trunks are covered by rhomboidal leaf bases having multicellular hairs in between. Crown of 10ft long pinnate compound leaves are present at the top.

Anatomy of Stem:

The transverse section of the stem shows roughly a circular outline. The epidermis is not very distinct due to the presence of heavy armor of leaf bases. The cortex is parenchymatous and traversed by mucilage canals and numerous leaf traces. The primary vascular structure consists of a ring of endarch, collateral, conjoint, and open vascular bundles encircling the pith. Pith is wide and parenchymatous. A ray-like extension passes between the vascular bundles that make their appearance discrete.

There is a cambium ring with a thin zone of secondary wood. The secondary wood encircles the primary xylem and consists of tracheids with scalariform and bordered pits. The secondary medullary rays traverse the secondary xylem and secondary phloem.

The C-shaped leaf traces arise singly from the primary vascular strand and entering the cortex divided into several masarch strands and enters straight into the leaf.

Anatomy of Leaf:

The pinnules show xerophilous structure. The upper and lower epidermis is heavily cutinized and thick walled. The mesophyll cells are distinguished into palisade and spongy parenchyma. The vascular bundles are mesarch and surrounded by bundle sheath.

Reproduction:

The reproductive structure is represented by flowers. In most of the species, the flowers are bisexual and arise in the axil of each leaf.

Structure of Flower:

The flowers are bisporangiate, stalked, and partially sunken in the leaf base armor. Rach such mature flower is 5-10cm in diameter and 10cm long. From the base of such flowers about 100 to 150 hairy bracts arise in close spiral little below the apex. These bracts formed a perianth like structure and protect the megasporangiate and microsporangiate parts of a flower. The microsporophyll or androecium forms a whorl united at the base into a sheath. The megasporophyll or gynaecium consists of numerous stalked ovules born around a central receptacle. Between the ovules, interseminal scales with expanded tips are present. These expanded tips fused to form a continuous surface with pores, through which the micropyle of ovules extended. The vascular supply of flowers consists of many branches from leaf traces.

Microsporophyll or Androecium:

The microsporophyll is 10-12cm long, consists of a central rachis bearing numerous pinnae. The pinnae bear two rows of bean-shaped shortly stalked pollen capsules or synangia. These pollen capsules are born on the trabeculae within the fertile region of microsporophyll. A line of dehiscence is also visible at the base of each microsporophyll. This suggest that the entire microsporophyll might have been shed as a unit. The pollen capsule or synangia measures about 3.5x2.5mm and its wall is several layers thick, the outer layer made up of palisade like cells, and the inner layer is made up of thin-walled cells followed by a tapetum. The tapetum was not demarcated. A ring of microsporangia arranged around the periphery of each synangium. The microsporangia dehisce longitudinally and release the microspores into the synangial cavity. At maturity, the synangia liberate these microspores outside by an apical opening that splits into two valves. The liberated microspores or pollens are oval, measures up to 68µ that represents the male gametophytes. Pollen grains of Cycadeoidea are multicellular.

Megasporophyll or Gynoecium

The gynoecium consists of a spherical or conical receptacle that bears numerous stalked orthotropous ovules and interseminal scales. Each ovule is about 1mm long and consists of the single integument that fused with the nucellus except at its apex.

According to Lignier, in C. morieri, nucellus is free from the integument. Each ovule has a pollen chamber and a nucellar beak. This nucellar beak is the extension of the integument. The ovules also have long micropyle, extended from the flat surface of interseminal scales. The fused tips of interseminal scales form an external protective covering or pericarp surrounding the seeds.

Crepet and Delevoryas discovered many of bisporangiate cones from the Cretaceous of black hills. They studied the structure of these ovules in detail. These ovules are urn-shaped and resemble with the ovules of C. wellsii. According to them the micropyle of these ovules are funnel-shaped due to the constriction below the flaring. The inner wall of the micropyle is lined with large cells, considered to be epidermal cells. The integument has three distinct layers. The outer fleshy layer of radially elongated cells, the middle stony layer made up of thick-walled cells, and the inner layer is fleshy.

The young nucellus is made up of thin-walled cells. The cells at the micropylar end are much elongated (80µ long) in comparison to the cells of the chalazal end. The cell at the nucellar tip is pointed up tp whereas cells on either side are bend outward to give the nucellus a distinct shape.

Crepet and Delevoryas reported a linear tetrad or row of three cells in the center of the nucellus.

The seeds are somewhat elongated or oval and possessed two cotyledons.

#exam season #send help #biology #notes #science #botany #gymnosperms #pines #pine trees #pine needles #plants #plant science #plant biology #nature #long post

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tentacion3099 · 4 months

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🌿

#afghanistan #military #botany #phytology #plant biology

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reasonsforhope · 3 months

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"In response to last year’s record-breaking heat due to El Niño and impacts from climate change, Indigenous Zenù farmers in Colombia are trying to revive the cultivation of traditional climate-resilient seeds and agroecology systems.

One traditional farming system combines farming with fishing: locals fish during the rainy season when water levels are high, and farm during the dry season on the fertile soils left by the receding water.

Locals and ecologists say conflicts over land with surrounding plantation owners, cattle ranchers and mines are also worsening the impacts of the climate crisis.

To protect their land, the Zenù reserve, which is today surrounded by monoculture plantations, was in 2005 declared the first Colombian territory free from GMOs.

...

In the Zenù reserve, issues with the weather, climate or soil are spread by word of mouth between farmers, or on La Positiva 103.0, a community agroecology radio station. And what’s been on every farmer’s mind is last year’s record-breaking heat and droughts. Both of these were charged by the twin impacts of climate change and a newly developing El Niño, a naturally occurring warmer period that last occurred here in 2016, say climate scientists.

Experts from Colombia’s Institute of Hydrology, Meteorology and Environmental Studies say the impacts of El Niño will be felt in Colombia until April 2024, adding to farmers’ concerns. Other scientists forecast June to August may be even hotter than 2023, and the next five years could be the hottest on record. On Jan. 24, President Gustavo Petro said he will declare wildfires a natural disaster, following an increase in forest fires that scientists attribute to the effects of El Niño.

In the face of these changes, Zenù farmers are trying to revive traditional agricultural practices like ancestral seed conservation and a unique agroecology system.

Pictured: Remberto Gil’s house is surrounded by an agroforestry system where turkeys and other animals graze under fruit trees such as maracuyá (Passiflora edulis), papaya (Carica papaya) and banana (Musa acuminata colla). Medicinal herbs like toronjil (Melissa officinalis) and tres bolas (Leonotis nepetifolia), and bushes like ají (Capsicum baccatum), yam and frijol diablito (beans) are part of the undergrowth. Image by Monica Pelliccia for Mongabay.

“Climate change is scary due to the possibility of food scarcity,” says Rodrigo Hernandez, a local authority with the Santa Isabel community. “Our ancestral seeds offer a solution as more resistant to climate change.”

Based on their experience, farmers say their ancestral seed varieties are more resistant to high temperatures compared to the imported varieties and cultivars they currently use. These ancestral varieties have adapted to the region’s ecosystem and require less water, they tell Mongabay. According to a report by local organization Grupo Semillas and development foundation SWISSAID, indigenous corn varieties like blaquito are more resistant to the heat, cariaco tolerates drought easily, and negrito is very resistant to high temperatures.

The Zenù diet still incorporates the traditional diversity of seeds, plant varieties and animals they consume, though they too are threatened by climate change: from fish recipes made from bocachico (Prochilodus magdalenae), and reptiles like the babilla or spectacled caiman (Caiman crocodilus), to different corn varieties to prepare arepas (cornmeal cakes), liquor, cheeses and soups.

“The most important challenge we have now is to save ancient species and involve new generations in ancestral practice,” says Sonia Rocha Marquez, a professor of social sciences at Sinù University in the city of Montería.

...[Despite] land scarcity, Negrete says communities are developing important projects to protect their traditional food systems. Farmers and seed custodians, like Gil, are working with the Association of Organic Agriculture and Livestock Producers (ASPROAL) and their Communitarian Seed House (Casa Comunitaria de Semillas Criollas y Nativas)...

Pictured: Remberto Gil is a seed guardian and farmer who works at the Communitarian Seed House, where the ASPROL association stores 32 seeds of rare or almost extinct species. Image by Monica Pelliccia for Mongabay.

Located near Gil’s house, the seed bank hosts a rainbow of 12 corn varieties, from glistening black to blue to light pink to purple and even white. There are also jars of seeds for local varieties of beans, eggplants, pumpkins and aromatic herbs, some stored in refrigerators. All are ancient varieties shared between local families.

Outside the seed bank is a terrace where chickens and turkeys graze under an agroforestry system for farmers to emulate: local varieties of passion fruit, papaya and banana trees grow above bushes of ají peppers and beans. Traditional medicinal herbs like toronjil or lemon balm (Melissa officinalis) form part of the undergrowth.

Today, 25 families are involved in sharing, storing and commercializing the seeds of 32 rare or almost-extinct varieties.

“When I was a kid, my father brought me to the farm to participate in recovering the land,” says Nilvadys Arrieta, 56, a farmer member of ASPROAL. “Now, I still act with the same collective thinking that moves what we are doing.”

“Working together helps us to save, share more seeds, and sell at fair price [while] avoiding intermediaries and increasing families’ incomes,” Gil says. “Last year, we sold 8 million seeds to organic restaurants in Bogotà and Medellín.”

So far, the 80% of the farmers families living in the Zenù reserve participate in both the agroecology and seed revival projects, he adds."

-via Mongabay, February 6, 2024

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