Water efficient horticulture in Mexico

Transcription

1 Water efficient horticulture in Mexico Using the water streams model of Wageningen Greenhouse Horticulture October 5 th, Bram Vanthoor, Ilias Tsafaras, Gert-Jan Swinkels, Erik van Os

2 Content Financing and project partners Mexico and water use in greenhouse horticulture Aim of the project Water saving technologies 5 Mexican companies Suggestions for each company Water and fertilizer use from low-tech to high-tech Summary and discussion 2

3 Financing and project partners Project is financed by Dutch government Seed Money Project Top sector Horticulture and Starting material Project partners: 3

4 Mexico and greenhouse horticulture Water becomes scarce, low quality High sodium concentrations Limited use of rain water and drain water recirculation 5

5 Mexico: potential of rain water Rain could cover 50% of irrigation water 6

6 Aim of the project To reduce water and fertilizer use in the Mexican greenhouse industry by integrating water technical know-how and solutions Reduce environmental impact Suggestions for the participating Mexican companies 8

7 Water saving solutions Using a water and nutrient flow model of Wageningen Research, the impact of the following technologies will be analysed: The shift from shadehouse to greenhouse The use of substrate cultivation The use of rainwater Different technologies to improve irrigation water quality Recirculating drain water 9

8 Water saving technologies transpiration Water flows rainwater EC ph filter nutrients nutrient solution disinfection reuse Water treatment Rain water basin Ground water/river water drainwater disinfected water

9 Water saving technologies Greenhouse Shift from shadehouse to greenhouse Advantages Indoor climate can be controlled and more light inside Relative humidity can be controlled which might reduce evaporation losses More crop per drop by increased crop yield Disadvantages Depending on local climate, a shadehouse might be more profitable than a greenhouse 11

10 Water saving technologies Hydroponics Shift from soil to hydroponics Advantages No soil related diseases No leaching off to soil More precise irrigation control Continuous feedback from drain measurements Disadvantages Good quality water required More precise control needed Less water buffer at plant roots more vulnerable 12

11 Water saving technologies Recirculation of drain Advantages Reuse of water and nutrients, up to 45% of water savings Disadvantages: Possible accumulation of sodium or other elements in substrate slab Drain water must be leached off Irrigation recipe must be adopted to drain sample Drain water must be disinfected before re-use In this study disinfection using UV light is used 13

12 Water saving technologies Rainwater basin Advantages High quality water - low sodium concentration: 10 times less than ground water Rain water covers a large part of water demand Low cost water technology Disadvantages Space needed for the rain water basin 14

13 Water saving technologies Treatment ground water Advantages Lower the EC and sodium concentration of ground water More nutrients can be reused Better crop quality due to lower sodium concentration Disadvantages Brine is produced (water is lost) 15

14 Water saving technologies Treatment ground water Principle Reverse Osmosis Semipermeable membrane Voltea Water flow between electrodes Aqua4D Electromagetic waves EC reduction < 0.1 EC 20-90% No reduction Brine 25-45% 10-25% 0% Advantages Proven technology. Tuneable EC reduction. Disadvantages Brine Brine New technology. No brine. Irrigation with higher EC possible. New technology, Elements stay in the water *Data comes from suppliers

15 Water stream model transpiration Water flows rainwater EC ph filter nutrients nutrient solution disinfection reuse Water treatment Rain water basin Ground water/river water drainwater disinfected water

16 Water stream model The model calculates for different scenarios: The supply to the crop based on water sources, water quality and fertigation recipe Water and nutrient uptake by the crop Water and nutrients in the drain Overall water and fertilizer use No impact of quality of irrigation water on production is modelled

17 Water stream model - assumptions Water leakage from soil to subsoil is 10% Enough rain water storage Drain will recycled till the maximum sodium in substrate: Sweet pepper: 4 mmol/litre Tomato: 8 mmol/litre Cucumbers: 8 mmol/litre Drain percentage: 25-45% Reverse Osmosis: brine 35%, EC reduction to 0.1 ms/cm* Voltea: brine 22.5%, EC reduced with 85%* Aqua4D: Maximum sodium in drain increased by 50%* *Data comes from suppliers

18 5 Mexican companies Greenhouse structure Crop Growing media Drain recircul ation Incoming water treatment to lower EC Using rain water as water source Location Shadehouse Cucumber Soil No No No Sinaloa Greenhouse Sweet Soil No No No Guadalajara pepper Greenhouse Tomato Hydroponics No No Yes Guanajuato Greenhouse Tomato Hydroponics Yes No No Querétaro Greenhouse Sweet pepper Hydroponics Yes Yes, reverse osmosis No Querétaro 23

19 5 Mexican companies local conditions Quality of fresh water source and rain water Location Main water source EC ph Sodium (mmol/litre) Sinaloa River Jalisco Ground water Guanajuato Ground water * Guanajuato Rain water Querétaro Ground water Querétaro Ground water Rainwater (mm) High sodium concentrations Quality of rain water is very good compared to other sources *Data comes from grower 24

20 Cucumber in soil in shadehouse (AgriCo) SH GH SL HP RW DR RO VOL A4D Abbreviations Shadehouse GreenHouse Soil Cultivation Hydroponics Rain Water Drain Reciclulation Reverse Osmosis Desalination with Voltea Aqua - 4D Shift to hydroponics: 29% more river water use, 48% more fertilizer use (USD 0.31/m 2 /year) Hydroponics and drain recirculation: no impact on water and fertilizer use due to good quality river water With rain water basin and drain recirculation 67% water saving and no impact on fertilizer use No need for RO since quality river water and rain water is good (low sodium < 1.1 mmol/l) 25

21 Pepper in soil in greenhouse soil (Sol de Sayula) SH GH SL HP RW DR RO VOL A4D Abbreviations Shadehouse GreenHouse Soil Cultivation Hydroponics Rain Water Drain Reciclulation Reverse Osmosis Desalination with Voltea Aqua - 4D Shift to hydroponics: 29% more ground water use, 56% more fertilizer use (USD 0.45/m 2 /year) Hydroponics and drain recirculation: 5% more ground water use, 12% more fertilizer use Rain water basin and drain recirculation: 84% of ground water will be saved. Sodium problem solved. 26

22 Sodium accumulation soil and hydroponics Much less sodium accumulation in substrate than in soil due to higher drain percentage 27

23 Substrate Guanajuato (Oliveros) SH GH SL HP RW DR RO VOL A4D Abbreviations Shadehouse GreenHouse Soil Cultivation Hydroponics Rain Water Drain Reciclulation Reverse Osmosis Desalination with Voltea Aqua - 4D Rain water basin and drain recirculation: 42% ground water saving and 34% fertilizer saving (USD /Ha) More fertilizers can be saved (up to 57%) by using RO, Voltea or Aqua4D 28

24 Drain recirculation Queretaro (FINKA) SH GH SL HP RW DR RO VOL A4D Abbreviations Shadehouse GreenHouse Soil Cultivation Hydroponics Rain Water Drain Reciclulation Reverse Osmosis Desalination with Voltea Aqua - 4D Rain water basin: 63% ground water saving and 28% fertilizer saving No much water savings at only Reverse Osmosis or Voltea (up to 13%) Up to 40% fertilizer saving (USD /year/Ha) possible by using RO, Voltea, Aqua4D 30

25 Drain recirculation Queretaro (Freshmex) SH GH SL HP RW DR RO VOL A4D Abbreviations Shadehouse GreenHouse Soil Cultivation Hydroponics Rain Water Drain Reciclulation Reverse Osmosis Desalination with Voltea Aqua - 4D Rain water basin: 62% ground water saving and no fertilizer saving Voltea instead of RO: 14% groundwater saving, 11% more fertilizer use. Aqua4D: much more drain water is leached off (accumulation sodium) thus more fertilizer consumption 31

26 Summary companies Scenario Current situation Total water use Fertilizer costs With water saving technology Groundwater Fertilizer Added technology savings savings Fertilizer savings m 3 /m 2 /cycle USD/m 2 /year % % USD/Ha/year SH_SL 0.4 $0.60 GH_HP_RW_DR GH_SL 1.0 $0.80 GH_HP_RW_DR GH_HP_RW 1.2 $4.00 DR_RO/VOL/A4D ,000 GH_HP_DR 2.1 $5.00 RW_RO/VOL/A4D ,250 GH_HP_DR_RO 1.8 $2.50 RW No fertilizer savings by shifting from soil to hydroponics Huge fertilizer savings possible by using drain recirculation and water basin Huge ground water savings possible for all scenarios 32

27 Summary for the companies For all scenarios: Rain water basin is a good solution to save ground water/river water Good quality irrigation water Much less sodium related problems More drain can be recycled In hydroponic greenhouses, huge amount of fertilizers can be saved by: Rain water basin and drain recirculation Technologies that lower the sodium concentration

28 The costs and value of water Ground water costs are extremely low: USD/m 3 Maximum costs 800 USD/Ha/year Investing in only water saving solutions is economically not profitable Investments must be paid back by: Fertilizer savings: up to USD/Ha/year Extra production and/or quality 34

29 Production Impact on production levels not taken into account in this study Technology improves quality of irrigation water and growing conditions Impact EC (sodium) in irrigation water on production 35

30 Production and water saving technology Production increase by: Better quality irrigation water (rain water, RO, Voltea, Aqua4D) Reduced sodium levels (hydroponics, rain water, RO, Voltea) Better controlled environment (greenhouse) No soil related diseases (hydroponics) Better control of fertilizers in system (hydroponics) Investments in water saving technology might be earned back by extra production 36

31 Summary Enormous savings for ground water and fertilizers The best water saving technologies depend on local conditions: Amount of rain water Availability and quality of ground water/river water Type of crop Fertilizer costs Reuse of rain water is the first step to save ground water, fertilizers and increases crop production With a water stream model the water and fertilizers savings can be calculated for each location and situation 39

32 The change has already started Source: Hortidaily 13/09/2017, New greenhouse Divemex 40

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34 Questions and discussion 42