Garden pond

Garden pond

Agarden pondis awater featureconstructed in awater gardenor designedlandscape,normally foraestheticpurposes, to providewildlifehabitat,or for swimming.

Habitat

Garden ponds can be excellent wildlife habitats and may contribute to the protection of freshwater wildlife.Invertebrateanimals (such asdragonfliesandwater beetles) andinsectivorousvertebratessuch asamphibians(frogsandtoads),turtlesandwaterbirdscan colonize new ponds quickly.Ornamental fishesare also frequentlystockedin larger ponds to provide aesthetics andalgaecontrol, as well aspest controlagainstmosquito larvaeinfestation.

Garden pond owners have the potential to make many original and valuable observations about the ecology of small waterbodies, which garden ponds replicate.

Problems

There are several problems that can result from garden ponds. In particular, they can be pathways for the spread ofinvasiveplants. In the UK, the invasive speciesCrassula helmsiiandMyriophyllum aquaticumhave both escaped from garden ponds. These plants cause considerable practical problems in protecting freshwater.

Amphibiousspecies such asfrogs,toads,andnewtsare common in garden ponds, especially in overgrown areas withalgaeandreeds.Without proper precautions being taken by pond owners, such areas can harbour excessivefrogspawnand may pose a challenge.

Cases of high rodent activity are also common in garden ponds, withfield mice,rats,andvolestaking refuge in freshwater areas such as garden ponds. Consuming pondwater contaminated with raturinecan cause infections such asWeil's diseaseorleptospirosis.

In tropical climates, garden ponds may become breeding sites formosquitoesand increase the spread of diseases carried by these insects.

Conditions

This garden pond has two ponds separated by a waterfall with a one-foot drop; generally, the fish in the upper pond are smaller, and ones in the lower pond are larger.

Ponds may be created by natural processes or by people; however, the origin of the hole in the ground makes little difference to the kind of wildlife that will be found in the pond. Much more important is whether the pond ispollutedor clean, how close it is to other wetlands and itsdepth,particularly whether it dries out from time to time and how many fish (if any) there are.

Naturally, ponds vary more in their physical and chemical conditions from day to day than other freshwater, like rivers. People often install pumps in garden ponds to counter these natural tendencies, particularly to maintain higherlevels of dissolved oxygen.Although this is generally unnecessary for wildlife, it may be essential to keep fish in a garden pond. For ponds with polluted nutrient-richtapwateradded to them, filters can be used to reduce the abundance ofalgae.

Water supply and loss

Ponds outside of gardens are fed by four main water sources:rain,inflows(springs and streams),surface runoff,andgroundwater.The wildlife value of ponds is greatly affected by the extent to which these water sources are unpolluted. Garden ponds are generally not fed by inflows or groundwater, except in the larger and rural gardens. Usually, the pond will be filled by a combination of tap water, rainwater, and surface runoff – and lost toevaporation.

In soils that lack naturalclay,additional water loss todrainageandpermeationis prevented by a liner.Pond linersarePVCorEPDMfoils that are placed between the soil of the pond bed and the water. Liners can also be made from puddled clay, and ponds on free-draining soils can even be self-sealing with fine sediments washed into the pond.

Seasonal ponds

Ponds tend to dry out if excessive water is lost to evaporation. Evaporation is more common in the summer season, when increases in temperature and lack of rainfall contribute to dry conditions, creating seasonal ponds (orvernal pools) that usually dry out once a year. These seasonal ponds provide specialized habitat for many plant and animal species, particularly amphibians and invertebrates. Oftentimes, seasonal ponds are utilized as a breeding ground, allowing amphibian (such asfrogsandtoads) and invertebrate (such asfairy shrimp)larvaespace to develop without aquatic predators like fish.

Natural ponds, natural pools, and swimming ponds

This German swimming pond highlights how natural swimming pools can be designed to resemble a part of the surrounding environment.

The traditional coping on this natural swimming pool demonstrates that natural swimming pools can be designed in many ways and do not always have to resemble natural bodies of water.

Ponds orswimming pondscan be constructed by an isolating membrane or membranes or (on anorganicmodel sometimes callednatural pools) contained by a layer ofloam.For all variants no chemicals or devices disinfect or maintain water, the water is instead cleared through the use ofbiological filters,aquatic plants,or otherorganisms used in water purification(zooplankton).

The first such pools were built in the early 1980s inAustria,where they are known as"Schwimmteiche".The first was built by Werner Gamerith and Richard Weixlerin Gamerith's private garden in the 1980s.The market slowly grew, and by 2016 there were around 20,000 such swimming ponds in Europe.

The first public swimming pool in North America built and maintained in this way, was finished at Webber Park inMinneapolisin 2015.

An organization called the International Organization for Natural Bathing Waters (IOB) sets the guidelines for such pools.

See also

• Biotope
• Koi pond
• Water garden

Further reading

• Shilton, Andrew, ed. (2006).Pond treatment technology.IWA Pub.ISBN9781843390206.