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戀上養耕共生

戀上養耕共生
Hooked on aquaponics

Brattleboro couple spreads the word about a more sustainable way of raising plants and fish
By Alexandra Ossola/The Commons
BRATTLEBORO—For visitors to the home of Mark and Susie Crowther, the blue plastic barrels can be the elephant in the room.
What are those barrels doing in a room of their own, people wonder, and why do they keep emitting sounds of rushing water?
They’re aquaponics systems — closed, symbiotic systems in which the Crowthers can efficiently raise plants for their consumption and fish, using recycled materials and water.
Aquaponics is gaining traction on a larger scale as an alternative to traditional methods of produce and fish farming. In developing countries with a limited water supply, people like aquaponics guru Travis Hughey are introducing the concept as a way for individuals to grow their own food while making the most of their limited resources.
Thanks to some research, seeds, water, fish, and a bit of creativity, Mark Crowther has become an avid aquaponics hobbyist, and he is working with the Bonnyvale Environmental Education Center (BEEC) in West Brattleboro to host two workshops in May.
Aquaponics has been used for centuries, as far back as the Aztec empire, when engineers from Tenochtitlan created floating islands of reeds on which they planted seeds for fruits and vegetables.
These days, though, the systems can be as large as lakes or portable and small enough to fit on a tabletop indoors.
To Crowther, the key to creating these systems is to tailor them to the space available; each one of his systems is built from several 55-gallon blue plastic barrels, one sitting cylindrically on the floor as a tank for the fish, the other half-barrel placed perpendicular on top of the other, as a larger plant bed.
There’s a large hole in the bottom barrel above the waterline so that he can access the fish (in Crowther’s system these are golden shiner minnows, “because they were available at the local bait shop,” he said).
The top half-barrel is full of expanded shale, which is Crowther’s “grow bed media” into which the seeds were planted.
This grow bed media is essential in any aquaponic system because it houses those bacteria that enable the plants to absorb the nitrogen. He chose the shale because it’s lightweight, porous, and local.
“But the grow bed media can even be free,” Crowther said. “You can just go down to a brook or river and pull out a bunch of pebbles.”
The final key component to this system is a small electric pump that brings the water from the fish’s bottom barrel to water the plants on the top barrel. A simple bell siphon then flushes the water back down to the fish tank once it fills to a certain level.
The nitrogen cycleThe concept behind aquaponics is based in the nitrogen cycle, which many of us learned in middle-school science class.
Nitrogen in the soil that was deposited by precipitation takes the form of nitrates, which plants need to grow. (Fertilizers incorporate nitrates for this reason.) All fish excrete ammonia, a nitrogen compound, which can kill them if it accumulates to too high a concentration in the water.
Plants are able to absorb that ammonia in the water with the help of the bacteria nitrosomona and nitrobacter. Because the water is recycled, a closed aquaponics system uses approximately 90 percent less water than traditional farming methods, and the system allows both the fish and the plants to exchange nitrogen to their mutual benefit.
Crowther’s interest in aquaponics came about as a synthesis of many other lifelong interests, primarily with aquariums, gardening, and science.
“[I saw aquaponics as] a way of getting back into traditional gardening and incorporating my passion for being an aquarium hobbyist in the past,” he said.
“We love to farm, but the drawback of traditional farming in Vermont is that once you harvest your food, you don’t get to start up until the following spring,” he added.
“With aquaponics you can grow a wide variety of crops year round,” Crowther said. “I thought maybe it would be interesting to get the fish into the system and farm in a way where I didn’t have to pull a weed.”
Crowther primarily grows cool-season vegetables — lettuce and a few spice plants (including mustard and cilantro) — in his system.
While his system is too small to raise fish that could be “table-ready” (that is, suitable for human consumption), larger systems could incorporate harvestable fish (trout, tilapia, perch, etc.).
Crowther preferred his first system to incorporate local species, which meant that they had to be cold-water fish.

With issues of overfishing from the world’s oceans and the myriad problems associated with fish farming (including larger environmental impact and escapement), aquaponics can seem like a panacea for those who raise fish.

However, the question rapidly arises if the artificial lights, pumps, and materials used in an aquaponics system are more cost effective than the fish and produce grown by more conventional methods used to raise the food that now appears in grocery stores.

Crowther believes that the best way to make these systems economically viable is to suit the systems to their climate; he intends to move his systems outside during the summer, replacing the artificial (and costly) heat and lighting with sunlight.

Tilapia has become popular with fish farmers because they “grow so quickly and reproduce like crazy,” Crowther said, but this type of warm-water fish would require too much heat to be viable here in Vermont.

Cold-water fish like perch and rainbow trout are better suited to the climate, and they still grow large and fast enough to be sold commercially.

To Crowther, aquaponics is ripe for taking hold in the region because “we are already invested in education, sustainability, and organic food and are confined to a short outdoor growing season.”

“Unfortunately, aquaponics has never gained ground on a commercial level in our area because of the brief exposure Brattleboro had to Carbon Harvest,” he said, referring to the currently stalled aquaponics endeavor on Brattleboro’s Old Ferry Road.

Carbon Harvest planned to grow tilapia and various types of produce, but has not gotten off the ground due to financial difficulties.




One of Carbon Harvest’s planning errors, Crowther said, might have been attempting to grow a warm-water fish, which meant that the entire building had to be heated to a tropical level that is simply cost-prohibitive.

“That was too bad for Brattleboro, but smaller systems could work for the community from more of a grassroots level, if not on a commercial level,” he said. “The idea is still worth spreading so people can see the value in farming this way.”

Crowther sees those who would be most interested in aquaponics as people who are interested in sustainable agriculture, who are curious about where their food comes from, who respect nature, and who want to bring some of it into their homes.

With some plans pulled from the Internet, some creativity and a do-it-yourself attitude, anyone can construct an aquaponics system.

“One advantage of this is that it’s not an elitist undertaking,” he said. “You don’t need much money to get started.”

Crowther is working with BEEC and Transition Putney to host workshops at the Putney Public Library on Wednesday, May 15, at 7 p.m., and Sunday, May 19, at 1 p.m., on aquaponics. Participants will learn how to construct their own portable aquaponics systems, and all ages are welcome.

“Once kids figure out that you can very easily adapt an aquarium to grow lettuce with a simple 10-gallon tank and a 5-gallon bucket, they’ll realize that it’s fun to watch things grow and will be interactive with this whole process,” he said.

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全日照  8個小時日照 瓜類、茄果類、豆類、山藥、豆薯(地瓜)。番茄、黃瓜、茄子、辣椒等喜溫中、強光性
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其次是根莖類,如:馬鈴薯、甜菜、胡蘿蔔、白蘿蔔、甘藷、山藥等等。至少需半日照,才能生長,芋頭雖喜歡全日照,但比其他蔬菜耐蔭。 
需要中等光照大白菜、甘藍、芥菜、蒜、洋蔥。 

長日性蔬菜白菜、甘藍、芥菜、蘿蔔、胡蘿蔔、芹菜、菠菜、萵苣、蠶豆、豌豆、大蔥、洋蔥。

短日性蔬菜豇豆、扁豆、莧菜、空心菜。         

中光性蔬菜黃瓜、番茄、茄子、辣椒、菜豆

菜豆

菜豆喜溫暖,不耐高溫和霜凍。菜豆種子發芽的適溫為20-30℃;在40℃以上的高溫和10℃以下的低溫,種子不易發芽。幼苗生長適宜氣溫為18-25℃。花芽分化的適宜氣溫為20-25℃,過高或過低溫度易出現發育不完全的花蕾、落花。

菜豆對光照強度的要求較高。在適宜溫度條件下,光照充足則植株生長健壯,莖的節間短而分枝多,開花結莢比較多,而且有利於根部對磷肥的吸收。當光照強度減弱時,植株易徒長,莖的節間長,分枝少,葉質薄,而且開花結莢數少,易落花落莢。

菜豆根系強大,能耐一定程度乾旱,但喜中度濕潤土壤條件,要求水分供應適中,不耐澇。生長期適宜土壤濕度為田間最大持水量的60%-70%,空氣相對濕度以80%為宜。開花結莢期對水分最敏感,此期土壤乾旱對開花結莢有不良影響,開花數、結莢數及莢內種子數減少。土壤水分過大時,下部葉片黃化,早脫落。空氣濕度過大會引起徒長、結莢不良。

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蝶豆花

蝶豆花 原產拉丁美洲的蝶豆花是一種典型的熱帶蔓藤植物,全年盛開。
butterfly pea,拉丁語叫:Clitoria ternatea,泰語叫Dok Anchan
中文名叫蝶豆花,藍蝶花,藍蝴蝶、蝴蝶藍花,還有蝴羊豆、豆碧等別名。
用蝶豆花當作高品位浪漫的茶品飲用、以及當作天然食品色素制作糕點是拉丁美洲和南洋國家的風情和習俗。
蝶豆花的味道自然甘甜,南洋國家的一些五星級酒店通常把蝶豆花茶當作高貴的迎賓茶來接待貴賓。
營養價值 蝶豆花具有豐富的維他命A,C和E, 而且可以提高免疫力, 幫助和促進皮膚的彈力和骨膠原, 同時還具有補腦,促進腦的活力,防止胃痛,抗憂郁、抗壓力、鎮靜、止驚厥、緩和情緒等天然保健功效。
蝶豆花中的天然藍色素,也是有療效的。如果將其加入檸檬並調制成花茶飲品,就是保健心臟血管的絕佳飲料。
食用價值 蝶豆花的可食部位是葉、花及嫩莢。較幼嫩的葉片及盛開的花朵,亦可拿來煮湯、油炸等。用嫩芽來炒肉絲或煮熟後食用,都十分可口。蝶豆花的葉及花的萃取液,可當作純天然的食品染料。

直達香草(herb4kitchen)
PS.營業用批量報價

錦鯉養殖基本知識

◎飼養與管理的重點 只要不是劇烈的變化,錦鯉很容易適應各水溫水質等環境的變化。並不是沒有大庭園就無法飼養,有人甚至在二樓陽台或頂樓陽台造水池飼養。然而我們是欣賞錦鯉雄壯豪邁之氣,因此水池盡量寬闊為宜,以水深1.2m以上為理想。魚池必須有底水排出,過濾循環等設備。用水不一定要取地下水,自來水也可以飼養。
<因為都市中有景觀安全的需求,及屋頂花園有荷重的需求,錦鯉池水深可以低到30cm左右。>
◎每天排水
A、糞或枯死的藻類全部送至過濾槽的話,耗氧量會增大,pH就下降,更會轉變為亞硝酸,增了過濾槽的負擔。為了盡量減輕過濾槽的負擔,每天至少把魚池的底水排水使固物排出去,把中間水送去沉澱槽及過濾槽。 
B、把固體廢物的魚糞集中排出,最好不要從池底打氣而是從排糞口的上方40~50公分打打氣。如此氣泡往上昇。池水產生對流。污物就集中於排糞口。
<可以設計水流把固體廢物盡量集中或排出到過濾系統中。>
◎過濾槽管理
A、細菌附著於濾材,分解固體廢物會消耗大量的氧。 
B、溶氧不足時,厭氧菌會把硝酸還原亞硝酸,或從碳酸氣發生沼氣,也會從硫酸分解產生硫化氫等有毒氣體。
<如果溶氧不足,可以優先把打氣設備放置到生化過濾槽中。>
◎溶氧要充份
A、水中溶氧不足的話,會影響錦鯉的生育,飼料的消化,,水質的維持等等。
B、硝酸,亞硝酸的濃度增高時,會影響溶氧量。所以優先去除硝酸及亞硝酸。
C、使用沸石可輕易去除硝酸,沸石量約等重於魚體總重量。
<沸石再生法,是將沸石浸泡25℃以上1:10食鹽水數小時,再以清水洗淨即可。>
◎水質的控制
水質硬度高的話,錦鯉肌膚經常會有少許充血的狀態。豔麗性也會慢慢消失,紅緋會上升。pH值低,肌膚變的很不好看,但是雖餵增色飼料,依然不見起色,徒增浪費。pH值7.1~7.5最適宜的。
◎鯉餌的重要性
良好的魚餌不會崩壞鯉的體型。餌的量也是在夏天水溫 高的時候,訂定停餌期間,才是整體來說使鯉變胖最重要的秘訣。如果還是想 要給很多餌的話,要增加循還量。錦鯉在水溫超過28度的時候,應給與相當於 鯉全體重量3%的餌。水溫25度時1.5%,水溫20度時0.3%,16度以下則要停止鯉餌,這就是鯉魚長得強壯的要訣。連續不斷地給鯉餌的話,引起內臟障礙, 而影響到鯉不會長壯,甚至導至體型的變歪。
◎魚病預防
水的管理與定期消毒都是很重要的步驟,…