《真菌学》课件真菌过滤污水

1、? ?真菌学真菌学? ?课件真菌过滤污水课件真菌过滤污水 Habitats, like people, have immune systems, which become weakened due to stress, disease, or exhaustion. Mycorestoration is the use of fungi to repair or restore the weakened immune systems ofenvironments. Whether habitats have been damaged by human activity or natural d

2、isaster, saprophytic, endophytic, mycorrhizal, and in some cases parasitic fungi can aid recovery. Mycorestoration is an infant science to humans, but a highly refined method used by nature for millions of years. As we open our eyes to the fungal opportunities, we soon see many mushrooms in their ro

3、les as environmental healers.Mycofiltration Mycofiltration is the use of mycelium as a membrane for filtering out microorganisms, pollutants, and silt. Habitats infused with mycelium reduce downstream particulate flow, mitigate erosion, filter out bacteria and protozoa, and modulate water flow throu

4、gh the soil. These fine filaments function as a cellular net that catches particles and, in some cases, digests them. More than a mile of threadlike mycelial cells can infuse a gram of soil. Mycofiltration membranes can filter the following: pathogens including protozoa, bacteria, and viruses silt c

5、hemical toxins They can be installed around the following types of sites: farms and suburban and urban areas Watersheds Factories Roads stressed, harmed, or malnourished habitats Installation of mycofiltration membranes can utilize debris from the following sources, which isthen inoculated with toxi

6、n-specific mushrooms : forests (brush, tree trimmings, wood chips) paper mills (cellulose, fiber, cardboard, or paper waste) city and rural recycling centers (yard waste) farms (straw, corncobs, cotton, coffee wastes, and so on) Breweries and other industriesMycofiltration: Germination of the Idea I

7、n 1970s, while studying at the Evergreen State College near Olympia, Washington, I peered at fungi through a scanning electron microscope and found the patterns of mycelia fascinating. I imagined that this fabric of fine cells could act as a biological filter. At that time, mycologists typically des

8、cribed mycelium as growing on habitats. I saw them as growing through the environment, filtering water after rains. I made filters by peeling mycelia from petri dishes and comparing their filtrationproperties to that of cotton. Mycelias absorbency of tobacco smoke, ink, and water was astonishing. So

9、 was the tenacity that held the mat tightly together. But my idea of mycelium as a filtration systemfell dormant until I bought a small waterfront farm on Kamilche Point in Skookum Inlet, Washington. On my land, 2 swales gradually narrowed over the course of about 800 feet, dropping 120 feet from my

10、 uplands to the saltwater bay downstream. A ravine led to a small waterfall directly above a bay where my neighbor grows clams and oysters for commercial purposes. My property came with a small herd of 6 Black Angus cows; chickens and pigs soon followed. Fecal coliform pollution directly threatenedt

11、he shellfish industry on the inlet. The livestock on my property was just one source of bacteria jeopardizing these family businesses. A few months after I moved in, the sheriff visited me and all the upland property owners along Skookum Inlet, serving us with court orders to install new septic syst

12、ems within 2 years or vacate the land. I installed outdoor wood chip beds of garden giants (Stropharia rugoso annulata) and other mushrooms at the top of one of these parallel sloping basins. To reduce coliform bacteria from an upland farm, two rows of woodchip-filled burlap sacks, inoculated with o

13、yster mushroom mycelium, catch surface water before entering a sensitive salt-water estuary in Mason County, Washington, USA. First, I dumped several truckloads of wood chips into the depression. The utility company trimming tree branches away from the power lines along my county road had provided t

14、he wood chips. On top of each dump load, I spread severalbags of Stropharia rugoso annulata spawn and then raked out the pile into a foot-deep layer. Springwater saturated the wood chipsa perfect environment for running mycelium. Several months later, I had a garden giant mycelial bed about 50 feet

15、wide and 200 feet long. The next summer, enormous mushrooms grew, providing delicious fare for many warm-weather barbecues. Just 1 year after I had installed my beds of mycelium, before I had even repaired my septic system, analysis of my outflowing water showed dramatic improvement: a hundredfold d

16、rop in coliform levels despite the fact I had more than doubled mypopulation of farm animals. The anomalous decline in fecal coliforms surprised the water quality inspectors monitoring the inlet. I explained to the inspectors that the contaminated water seeped from our livestock pasture, entered thi

17、s mycofilter, and fed the myceliated wood matrix with nutrients and bacteria. As the fungus grew, the wood chips became infused with white, silky mycelium. The water that exited our wood chip bed was largely cleansed of bacteria, which had been consumed by the mycelium of the garden giant. That my b

18、ackyard mycofiltration experiment reduced populations of coliforms drew the attention of researchers at the Battelle Marine Science Laboratories in Sequim, Washington. More-formal studies ensued, demonstrating that other mushroomsoysters and wood conk mushroomsalso functioned as microbiological filt

19、ers.Mycofiltration of Microbial Pathogens Mushroom mycelium has an unquenchable appetite for organic debris. Taking advantage of this appetite, the mycological landscaper can select mushroom species that target and consume the bacteria and protozoa in a habitat. Lovy and others (1999) found that my

20、strain of zhu ling (Polyporus umbellatus) was 100 percent effective in vitro in inhibiting the malarial parasite Plasmodium falciparum. Mycomulchinginfusing a layer of wood chips with myceliumwith this species around a malaria-infected swamp could reduce the background population of malaria, since t

21、he fungus likely consumes the parasite and secretes antibiotics into the habitat. Mycofilters can also prevent infection fromcoliform or staph bacteria and protozoa. The mycofilters can even trap disease-carrying insects, and protecting our health. Pathogens passing through the cellular nets of myce

22、lia are digested by the fungi. If enzymes and antibiotics secreted by the mycelium dont kill all the pathogens, the bacteria, such as Bacillus subtilis, are blocked from reproducing and are suspended in a state of dormancy. These types of bacteria may later revive when the mycelial mat dies and a ho

23、spitable habitat reemerges. Mycologists call this dieback, a process that is analogous to the decay of a fishing net that loses its cohesiveness and unthreads. In another field trial, I built a pond to catch the surface water flowing from the high part of our property. Measuring about 150 feet by 50

24、 feet and around 10 feet deep, our pond contained mostly rainwater, supplemented with groundwater pumped from a well. Testing the water that flowed from it, I found that the predominant bacterium was Pseudomonas fluorescens, the probable cause of the rash I got after taking a brisk swim there on a h

25、ot summer day. When we placed straw bales inoculated with oyster mushroom mycelia into the slough, channeling the runoff water through the straw, lab analysis found that the benign and omnipresent Bacillus subtilis reigned supreme while the upstream dominant Pseudomonas fluorescens failed to registe

26、r in the top 5 bacteria downstream. In just this way, matching the mushroom species to the problematic bacteria, ecological engineers can customize mycofilters to prevent upstream pathogens from passing into downstream environments. Several factors affect the efficiency of mycofiltration: slope, flo

27、w rate, turbidity, straw shaft diameter, mushroom species, degree of mycelial colonization, and microbial populations.Mycofiltration around Farms Manure pondscommonly amassing around cattle, hog, and chicken factory farmsare bursting with fecal-rich effluent leaching into the watersheds. River ecosy

28、stems are imperiled. Pfiesteria, Listeria, Streptococcus, Escherichia coli, amoebic parasites, and viruses are posing increasing human health risks as corporate farming policies aim for profit at the expense of environmental health. Factory farms, which crowd livestock into tight quarters for effici

29、ent feeding and slaughtering, are causing an overly focused and growing outflow of waste products that threaten the health of all. This outflow may have exceeded the amount that our habitats can absorb. Hog farms are particularly worrisome to environmental scientists. When hurricane Floyd hit North

30、Carolina in 1999, the rains caused dikes to burst and manure ponds to overflow, flooding thousands of acres with animal feces and causing incalculable health problems both on and off the farms. Residents in Charlotte were rudely awakened to the enormity of the problem by the fouling on their doorste

31、ps. Filth filled the streets and flooded basements. The collateral damage included contaminated wells, fisheries, and crops. Many diseases spread, including ones pathologists are still at a loss to identify. This ecological mess eroded the public trust in farmers as good neighbors. Corporate giants

32、responsible for this dangerous situation play political football by demonizing opponents, especially supporters of government regulations, and by pitting farmers against environmentalists. Practical proposals for fixing these problems, let alone proven remedies, have been few and far between. A vari

33、ety of forms of mycelial mats can prevent downstream pollution. I am keen on using mycelium in burlap sacksto build mycelial buffers to capture microbes and nutrients.Installing a Mycofilter A gently sloped area below a feeding lot or manure pond, where effluent from the lot or pond continually seeps through, is an ideal site to install a mycofilter, essentially a myceliated organic drain fie