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養耕的現狀

How Aquaponics Works
They say one person's trash is another's treasure. The day-old bagels a franchise views as too stale for customers taste perfectly delicious to the hungry when they're distributed at a homeless shelter. The annoying, hyperactive puppy one family abandons at the dog pound because it chews shoes becomes another family's rambunctious little delight. What one group sheds as waste, another takes in as nourishment. It's a lovely circle.
With aquaponics, this same circle is turning -- only it doesn't have anything to do with bagels or puppies. Aquaponics is a method of cultivating both crops and fish in a controlled environment. The fish are kept in tanks, and the plants are grown hydroponically -- meaning without soil. They sit in beds, but their roots hang down into a tub of water. When fish live in tanks, their waste builds up in the water, and it eventually becomes poisonous to them. But what is toxic for fish is nourishing for plants -- they love nothing more than to suck down some fish waste. So with aquaponics, the fish waste-laden water from the fish tanks is funneled to the tubs where the plants dangle their roots. When the plants absorb the nutrients they need from that water, they basically cleanse it of toxins for the fish. Then that same cleansed water can be funneled back into the fish tanks.

This method of farming fish and crops is a good thing on several different levels. First of all, it removes fertilizer and chemicals from the agricultural process. The fish waste acts as a natural fertilizer for the crops, instead. Second of all, it saves water because the water is recycled within the tanks rather than sprayed across a field of crops with abandon. Thirdly, an aquaponics environment can be set up anywhere, so it reduces the need for local communities to import fish and crops from other countries. That saves fuel -- also a positive.
­Aquaponics, with its fancy name, may sound like a trendy new concept developed by environmentalists. But it's actually as old as the hills. The origins of aquaponics can be traced to ancient Egyptian and Aztec cultures. The ancient Aztecs developed chinampas, man-made floating islands, which consisted of rectangular areas of fertile land on lake beds. Aztecs cultivated maize, squas­h and other plants on the chinampas and fish in the canals surrounding them. The fish waste settled on the bottom of the canals, and the Aztecs collected the waste to use as fertilizer [source: Growfish]. Additionally, countries in the Far East like Thailand and China have long used aquaponic techniques in rice paddies.

Let's learn how this ancient farming method is applied today.
Aquaponics Basics
Cultivating plants and fish through aquaponics is both easy on the environment and easy on finances. Aquaponic systems don't use any chemicals, and they require about 10 percent of the water used in regular farming. The systems are closed -- that is, once they've been filled with water, only a small amount is introduced into the system thereafter to replace evaporated water. But how can a water-based system use less water than conventional farming?

The answer is the continual reuse and recycling of water through naturally occurring biological processes. Basically, the waste from fish produces natural bacteria that converts waste like ammonia into nitrate. This nitrate is then absorbed by plants as a source of nutrients. The basic principle of aquaponics is to put waste to use.

Let's take a look at the step-by-step process:

Fish living in aquaponic tanks excrete waste and respirate ammonia into water. Ammonia is toxic to fish in high concentrations, so it has to be removed from the fish tanks for fish to remain healthy.
Ammonia-laden water is processed to harvest helpful types of bacteria such as Nitrosomonas and Nitrobacter. Nitrosomonas turns ammonia into nitrate, while nitrobacter converts into nitrate. Both of these nitrates can be used as plant fertilizer.
Nitrate-rich water is introduced to the hydroponically grown plants (plants grown without soil). These plants are placed in beds that sit on tubs filled with water, and the water is enhanced by the nitrate harvested from the fish waste. The plants' bare roots hang through holes in the beds and dangle in the nutrient-laden water.
The roots of the plants absorb nitrates, which act as nutrient-rich plant food. These nitrates, which come from fish manure, algae and decomposing fish feed, would otherwise build up to toxic levels in the fish tanks and kill the fish. But instead, they serve as fertilizer for the plants.
The hydroponic plants' roots function as a biofilter -- they strip ammonia, nitrates, nitrites and phosphorus from the water. Then, that clean water is circulated back into the fish tanks.
Because fish waste is used as fertilizer, there's no need for chemical fertilizers. The money and energy it would take to put those chemicals to work is saved. In fact, the only conventional farming method that's used to operate an aquaponics system is feeding the fish.

Now you know how aquaponics works on a biochemical level. But which kinds of fish are best for these systems? And which plants thrive in them? Let's find out.

Aquaponics System Requirements
Many warm-water and cold-water fish species have been adapted to aquaponics systems. The most commonly cultivated fish in aquaponics systems are tilapia, cod, trout, perch, Arctic char and bass. But out of all of these, tilapia thrives best. Tilapia are very tolerant of fluctuating water conditions, such as changes in pH, temperature, oxygen and dissolved solids. They also are in high demand -- this white-fleshed fish is frequently sold in markets and restaurants.

Which plants thrive well in aquaponics systems? That depends on the density of the fish tanks and the nutrient content of the fish waste. In general, the best plants to cultivate in an aquaponics system are leafy greens and herbs. The high-nitrogen fertilizer generated through fish waste allows plants to grow lush foliage. So, leafy plants tend to flourish in aquaponics systems. Lettuce, herbs and greens like spinach, chives, bok choy, basil, and watercress have low to medium nutritional requirements and usually do well in aquaponics systems.

Plants yielding fruit have higher nutritional requirements, and although they grow well in aquaponics systems, they need to be placed in systems that are heavily stocked and well established. Vegetables like bell peppers, cucumbers and tomatoes can be cultivated in these types of aquaponics systems. The only plants that don't seem to respond as well are root crops like potatoes and carrots. Without soil, these crops wind up misshapen, and they're hard to harvest properly.




Aside from plants and fish, the other major component of aquaponics is the water itself. That said, carefully monitoring the water's pH, which determines acidity, is of the upmost importance to ensure safe levels for the fish. Water quality testing equipment is very important to ensure that both fish and plants remain healthy. It's also important to keep an eye on dissolved oxygen, carbon dioxide, ammonia, nitrate, nitrite and chlorine. The density of the fish in the tanks, the growth rate of the fish and the amount of feed they're given can produce rapid changes in water quality, so careful monitoring is important. Although the ratio of fish tank water to hydroponic product depends on fish species, fish density, plant species and other factors, a general rule of thumb is a ratio of 1:4 tank contents to bed contents. Basically, for every one part of water and fish, you'll want to have four parts plant and bed material.

Some aquaponics systems are outfitted with biofilters, living materials that naturally filter pollutants out of water and that facilitate the conversion of ammonia and other waste products. Other systems feed fish waste directly into the hydroponic vegetable beds. Gravel in the vegetable bed acts has a bioreactor, a material that helps carry out the chemical processes of living organisms. The gravel does this by both removing dissolved solids and providing a place for the nitrifying bacteria to convert into plant nutrients.

Want to bring food production into your backyard? Read on to learn how to set up your own aquaponics system.

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蔬菜對溫度日照條件的要求

蔬菜對溫度日照條件的要求
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
蔬菜夏秋季生產,玉米、青椒、西瓜、南瓜、西紅柿、茄子、芝麻、向日葵類。
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。

菜豆具有深根性和根瘤菌,對土壤的要求不甚嚴格,但仍以土層深厚肥沃、排水良好的輕砂壤土或粘質壤土為好。土壤過於粘重、低溫、排水和通氣不良則生長不良,炭疽病重。菜豆喜中性至微酸性土壤,適宜的土壤pH為5-7.0,其中以州6.2-6.8最適宜。菜豆最忌連作,生產中應實行2-3年輪作。

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…

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,…