The document discusses several issues related to water usage and conservation in agriculture. Climate change is reducing water availability through lower rainfall and higher evaporation rates. To reduce evaporation losses from reservoirs and irrigation, the document recommends covering water surfaces, using floating barriers, and planting trees and aquatic plants around bodies of water. Effective treatment and storage of rainwater and surface water runoff is also emphasized to maximize available water resources for agriculture.

1. By : Jervis E Rowe(Abbey Garden Farm, Central Greenhouse Supplies & Services)

3.  Rainfall is declining
 Evaporation rates are increasing
 Climate is warming up

4.  Quantity of water reaching reservoirs, rivers
and streams is decreasing
 Evaporation losses from the above sources is
increasing
 Irrigated plants are demanding more water
as temperature rises

5.  To purchase and transport water for
Agriculture is too expensive
 To implement measures to reduce
evaporation will increase your cost of
production
 To do Agriculture with out water is impossible

6.  Evaporation of water occurs when the
exposed surface looses molecules to the
atmosphere in the for of water vapor
 Water vapor rises to form clouds

7.  Humidity
 Speed of air passing over the water
 Temperature , ( 1degree C reduction in temp.
can mean 2,900 gallons water saved
/acre/day.)

9.  Keep water cool
 Keep water depth above 3 ft
 Cover water

10.  Floating covers
 WER (Water Evaporation Retardants)
 Aquatic Plants
 Trees, shrubs and bushes
 Trellising system with a vine crop
 Less disturbance to water surface

11.  Acts as a barrier between water surface and
the air
 Reduces speed of air passing over the water
 Reduces contamination of water, falling
debris , algae and other water plants
 Reduces break down of pond liners

13.  Creates a film over the water surface
 Example : AcilolTA 618 , emulsion made from
a fatty alcohol

14.  Shades the water below
 Absorbs some of the solar radiation
 Examples: water lilies, floating hearts
 Far less expensive when compared to floating
covers

16.  Planted outside and around the pond
 Use plants that do not shed a lot of leaves or
pods eg. Evergreens

17.  Provides shade and wind break
 Example: beans, passion fruit

18.  Reduce splashing at water surface
 Allow inlet pipes to touch water
 Avoid the use or water wheels where possible

19.  Chlorophyll containing plant existing very low
on the evolutionary chain
 3 main groups , filamentous , branched ,
planktonic
 May occur single, colonies or mat
 Reproduces asexually AND asexually

21.  Pond size and depth
 Water stagnation
 High nutrients and light

22.  Small & shallow=high light & temp=algae
 Stagnant water, limited wave action
promotes growth
 High P & N is food for Algae

23.  Creates blockages ( pumps, filters, emitters,
meters, wheels and gates
 Reduces water quality( reduces oxygen,
causes contamination)
 When algae die they sink to the bottom of
the pond and contributes to the build up of
sludge

24.  Physical/ Mechanical control
 ChemicalControl
 Biological Control

25.  Rake out mat form algae
 Result is immediate
 No chemical cost or risk
 Algae removed can be used as mulch

26.  Organic
 Oxidizing agent
 Breaks down to water and oxygen( relatively
expensive)

27.  In use for several years
 Used as recommended has no adverse effects

28.  Blocks part of the light spectrum that algae
need to photosynthesize
 Example : Aquashade ( product name)

29.  Use of organism that feed on or rob algae of
their food or oxygen
 Triploid grass carp eat algae when other food
is limited

30. These may include but not limited to :
 Bacteria eg. Salmonella E Coli
 Protozoa eg. Crytosporidium , Giardia
 Viruses eg. Noroviruses

31.  Ph 4.5-6.5
 Temperature above 45degrees F
 0.2- 1.0 ppm iron in water
 0.1 or more ppm of Hydrogen Sulfide in water
 Bacteria produces slime which affects water
quality

32.  Best done locally with chlorine
 Ultra violet ray flow cells ( expensive)
 Osmosis (expensive)

33.  Chlorine disrupts cell membrane
 Cell looses contents
 Cell looses function
 Micro-organism dies

34.  Light penetrates cell
 Disrupts DNA , prevents reproduction
 Kills up to 99.99% bacteria and viruses
 Does not alter water ( taste and odor)
 Does not add chemical
 Use very little energy
 Low maintenance ( change bulb annually)

35.  Oxygen is electrically charged to produce ozone
( O2--- O3)
 Ozone is very unstable and will react with
material in an oxidizing reaction
 Ozone is one of the strongest sterilizing agents
 Apply ozone using a venturi or centrifugal pump
 After oxidation of ozone oxygen is left in solution

36.  Rain water which sometime gets to the Island
from other region must be harvested and
effectively stored
 Water already here must be screened for quality,
corrected accordingly and properly stored
 Surface water from roads, parking lots or other
paved areas can be harvested and treated for
certain agricultural uses
 Irrigation techniques must be efficient and
reflect best practices