永續農業: Riverbend's aquaponics project in Gladwyne


Riverbend's aquaponics project in Gladwyne

Given its location on a steep, densely wooded hillside at the very edge of Lower Merion Township, Riverbend Environmental Education Center’s 30-acre preserve in Gladwyne is not the most likely place to picture a modern-day farming operation.

But that is exactly what is expected to be up and running there by early next summer.

And given Riverbend’s mission to protect this gem of open space while helping area residents – young and older – to appreciate and better understand their place in the balance of nature, it should not be surprising that the farm it has in mind will be a model of sustainability.

Nearing the end of a major capital campaign, the center expects to go to bid this month for construction of a large greenhouse to contain an aquaponics project. The facility which will be the focus of new educational programs, is expected to be in operation for the start of summer camps in 2014 – and for Riverbend’s 40th anniversary celebration in June.

Aquaponics is the relatively new combination of two more established farming models: aquaculture – the farming of fish – and hydroponics – growing plants with nutrients supplied by water. When put together, they form an integrated system that requires no soil and, in Riverbend’s model, will operate solely on collected rainwater.

The $800,000 project has been the focus of a major fundraising campaign, which is three-quarters of the way to its overall goal, said Riverbend Executive Director Laurie Bachman in a recent interview at the center’s main building, its signature red barn. The campaign, as of late November, was just $30,000 shy of the first phase goal of $600,000 that will enable construction to begin in early spring..

Bachman said the idea for an aquaponics project grew out of the center’s most recent master site development planning in 2010. A number of improvements had been proposed, to be supported by the center’s successful application for a $300,000 grant of Pennsylvania Redevelopment Assistance Capital Project (RACP) funds.

While that process was going on, Bachman said she had met an Exton architect, Brian Hillestad, founder of a new non-profit organization called Veteran Community Farms when he was interested in using the barn for an event.

Hillestad’s idea was to use aquaponics as a means to provide jobs and training for returning military veterans. He was inspired to create the organization when he heard statistics that one in five homeless men in American is a veteran of military service.

More comment in western states, aquaponics is still quite new in the East, Bachman explained. Locally, there is a large, well-established aquaponics operation at Cheyney University, using a 10,000-square-foot greenhouse. Products – fish and typically basil or lettuce – are sold to local restaurants and at farmers’ markets.

When she first heard about Hillestad’s organization, Bachman said Riverbend was not in a position to engage in it. But about a year later, when the center had applied for the RACP grant, “It occurred to me, maybe instead of some of the projects [in the master plan] we could do an aquaponics project.”

While the projects in the master plan are valuable – one involves building a new, larger pond to support Riverbend’s popular pond life programs – they would also add expenses to the center’s operating budget.

“Aquaponics was an opportunity to go into an educational area we don’t currently touch – sustainable farming,” she explained. At the same time, with a partner like Veteran Community Farms handling day-to-day operations, it would also provide a revenue stream to support Riverbend’s programs and perhaps those future master plan improvements.

Plans were developed for a 4,380-square-foot greenhouse to be built on a portion of the property closely overlooking the Schuylkill Expressway that, because of the highway noise, was not as useful for educational purposes. In the master plan, it had been identified as a composting area.

The $800,000 cost of the project includes the greenhouse and rainwater collection system,, rain gardens to also control stormwater runoff, improvements to a trail leading to the greenhouse location, and the installation of composting toilets to serve visitors and employees of the aquaponics operation.

Earlier this year, Riverbend obtained needed zoning and land development approvals from Lower Merion Township for the project.

This is how the farm will work. Fish, typically tilapia, will be grown in a large tank. Water from the tank containing nutrients from fish waste and algae is filtered and pumped to shallow beds in which basil, lettuce or other greens have been planted in a gravel base. The plants filter the water, which is recirculated to the fish tank.

It’s estimated that an operation of this size could produce 40,000 heads of lettuce or 10,000 basil plants and 3,200 pounds of tilapia annually.

At the same time, the environmental benefits of this year-round, non-weather-dependent farming method include that no pesticides are needed, the use of fossil-fuel products is eliminated, rainwater is recycled, and several times more food can be produced with less man-hours than traditional farming. Aquaponics has been called the “most sustainable, naturally grown agriculture for the future.”

This will be Veteran Community Farms’ first large operation in the area, Bachman said. “They wanted to work with us because of the opportunity for educational programs” and because of Riverbend’s location with easy access to Philadelphia
Before embarking on the project, “We did preliminary surveys. There seemed to be a lot of interest,” Bachman said. “People have started to hear about it,” she added. Teachers are interested because tours and lessons at the farm will engage students; colleges are interested in internship opportunities. Also important, Riverbend saw an opportunity to increase educational interest for adult visitors. “There are so many opportunities, and we’re not even talking about [the] food [produced] yet.”

“It’s such a privilege for us to present cutting-edge, sustainable agriculture,” Bachman said. She hopes Riverbend’s project can be a model for other farms in the area or even homeowners, who might want to try aquaponics “on a small scale” in their backyards.

Bachman said the project has seen generous support from corporate donors and others to meeting the fundraising goals. Contributions are still needed to close the remaining gap. Information about how to support the project can be found at www.riverbendeec.org.

If all goes as planned, the project will be launched with a ribbon-cutting next June 7 as a part of a celebration of 40 years of stewardship and environmental education on the land, initially set aside by members of the Wood family from their much larger Gladwyne estates.

In those 40 years, environmental education programs for local and Philadelphia area schoolchildren have grown tremendously, Bachman said, serving 17,000 children in 2013, double the number of just six years ago.

At the same time, progress has been made to preserve and restore the land. Since 2008, volunteers have planted some 2,000 trees. Where forest “was becoming quite degraded by invasive plants and deer over-browse,” Bachman said, “we’ve started restoring it to a natural, native landscape.”

“The Wood family wanted to preserve this open space for the community,” she said. “It has not been an easy road, but people have really cared, and the aquaponics project will help ensure that.”




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









菜豆生育過程中,主要吸收鉀和氮較多,還要吸收一定量的磷和鈣,才能良好發育。結莢期吸收磷鉀量較大。磷鉀肥對菜豆植株的生長發育、根瘤菌的發育、花芽分化、開花結莢和種子的發育等均有影響。缺乏磷肥,菜豆嫩莢和種子的品質和產量就會降低。缺鈣,幼葉葉片捲曲,葉緣失綠和生長點死亡。缺硼,則根係不發達,影響根瘤菌固氮,使花和豆莢發育不良。 耐陰半陰(大概3-4小時日照) 應選擇耐陰的蔬菜種植,如萵…


◎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。
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。


英文版, English version
中文版, Chinese version
西班牙文版, Espanol version 

連通管基本原理 1.連通管原理指的是,在一般開放的空間中,幾個液體容器的底部都相通的裝置,而若任一容器內注入液體,則當液體靜止時,各容器的液面必在同一水平面。

2.兩 端的大氣壓力一樣,但管內兩端的水受重力作用而各自下墜,下墜瞬間,在圓弧頂部拉出一個真空,因真空而有壓力差,此時兩端的大氣壓 力再次從兩端將兩管的水壓回,但壓回的力量是大氣壓力減去管內的水壓(F=(Patm-PH2O)*A),而長管內的水比短管內的水還要重,所以壓回的力 量是短管的壓力大於長管的壓力,所 以,虹吸管內的水就會不斷的由短管端流入而由長管端流出。


4.如果用兩根連通管,但是其中一個連接抽水馬達,此時一根連通管是抽水,所以另一根把水送回,大氣壓力將兩管的水平衡,所 以,一個馬達可以有兩倍的動力,水就會不斷的循環。


簡易潮汐開關 (外部連通管) 1.由於水持續進入水箱,水在水箱和潮汐開關內以同樣的速度上升。(潮汐開關內的底部是連通的)。虹吸管是通到外部的。水會持續上升到外部的開口端。 2.一旦水上升到內部的開口端,它變成一個密封空間。由於水繼續上升,在水箱內水位繼續上升,但速度變慢。同時,水箱內水壓漸大。
(同時會將管道上端部份空氣帶出,因為空氣在管內流動,也是噪音最大的時候) 4.由於水在水箱到達高水位線後,體積空氣被迫壓縮管道,並透過虹吸作用,排出的空氣壓力後,進而開始大量排水。

1.由於水持續進入水箱,水在水箱和潮汐開關內以同樣的速度上升。(潮汐開關內的底部是連通的)。虹吸管是通到外部的。水會持續上升到內部的開口端。 2.一旦水位上升到內部的開口端,直接…