Analysis of Plant Biomass Production Comparing Decoupled Aquaponics Against Equivalent Single-Loop Aquaponic and Hydroponic Systems Growing Lactuca sativa
Metadata
- Cite key: lucasAnalysisPlantBiomass2020
- Item type: Thesis (Master’s — M.S. in Freshwater Sciences and Technology)
- Authors: H.L. Lucas
- Affiliation: School of Freshwater Sciences, The University of Wisconsin-Milwaukee
- Journal: The University of Wisconsin-Milwaukee (thesis; no journal — institution given per template convention for theses)
- Date: 08/2020
- Date added: [not reported]
- DOI: no DOI found
- Funding: [not reported]
- URL: [not reported]
- PDF:
Lucas - ANALYSIS OF PLANT BIOMASS PRODUCTION COMPARING DECOUPLED AQUAPONICS AGAINST EQUIVALENT SINGLE-LOOP A (34).pdf
Opinion
Not evaluated — extraction only.
Abstract
Aquaponics is an emerging method of agriculture in which fish and plants are grown in an enclosed and recirculating environment. The method mimics a relationship found in nature where fish waste provides nutrients for plants and plants cleanse the water for the benefit of the fish. This symbiotic relationship has proven to be a sustainable method of agriculture in which there is less water use, no need for pesticides or herbicides, recycling of nutrient waste and a smaller spatial footprint. However, the production of both plants and fish in a recirculating aquaponics system has produced less yield and profit when compared to its competitive counterparts, hydroponics and RAS (recirculating aquaculture system) methods. To address this issue, the traditional single recirculation aquaponics system (SRAPS) has been reengineered to a decoupled recirculation aquaponics system (DRAPS). The main differences of the DRAPS system is 1) solid waste from fish is mineralized and sent to the hydroponic plant grow system; 2) water from hydroponic system does not return to the fish; and 3) separate aquatic environments for fish and plants allow for the caretaker to create ideal growing conditions based on the specific needs of the culture organism. The objective of this study was to compare the yield of lettuce, Lactuca sativa, against three systems, hydroponics, SRAPS and DRAPS. The results of this study suggest that aquaponic environments provide a more habitable environment for plants to thrive over comparable hydroponic environments. Further research must be done to refine DRAPS and create a sustainable agriculture system to feed a growing world with less resources.
Summary
This Master’s thesis (University of Wisconsin-Milwaukee, School of Freshwater Sciences, 2020) set out to compare lettuce (Lactuca sativa) biomass production across three grow systems: hydroponics, a traditional single-loop recirculating aquaponic system (SRAPS), and a decoupled recirculating aquaponic system (DRAPS) in which solid fish waste is mineralized separately and routed to the plant unit without hydroponic water returning to the fish. The Table of Contents indicates the work included two experimental trials (Trial 1 and Trial 2), a materials/methods chapter describing system engineering and data collection, a statistical analysis, and results on environmental/water conditions, lettuce biomass, and root growth. The author concludes that aquaponic environments (both SRAPS and DRAPS) provided a more habitable growing environment for lettuce than hydroponics, and that DRAPS requires further refinement. Important caveat: the PDF available in this vault is only an 11-page front-matter excerpt (title page, ProQuest notice, abstract, copyright page, table of contents, list of figures/tables, acknowledgements, and the first page of Chapter 1) — it does not contain the Materials and Methods, Results, Discussion, Conclusion, Tables 1–2, or Figures 1–6 that the Table of Contents references (through at least p.44). No numeric result, treatment-level statistic, or methodological detail beyond the abstract’s summary sentences could be extracted.
Experiment
Design: Not reported in available text — abstract and Table of Contents indicate a controlled comparison of hydroponics vs. SRAPS vs. DRAPS growing lettuce, across two experimental trials (Trial 1, Trial 2), with a dedicated statistical analysis section (2.4), but Chapter 2 (Materials and Methods) content itself is not present in this PDF.
Sample size / replicates: [not reported] — not present in available text.
Duration: [not reported] — not present in available text.
Key outcome: Abstract states aquaponic environments (SRAPS and DRAPS) provided a more habitable environment for lettuce than hydroponics; no effect sizes, means, or p-values are given in the accessible text.
Materials and Methods (as available)
Not extractable. The Table of Contents lists Chapter 2 sections “2.1 Experimental Design,” “2.2 Engineering the Grow Systems,” “2.3 Data Collection,” and “2.4 Statistical Analysis” (pp.8–13), but none of that chapter’s body text is present in this PDF — the file ends one page into Chapter 1 (Introduction).
Results (as available)
Not extractable. The Table of Contents lists Chapter 3 “3.1 Environmental and Water Conditions” (p.15), “3.2 Lettuce Biomass Production” (p.16), and “3.3 Root Growth Response” (p.18), plus Table 1 (environmental growth conditions, Trial 1 and Trial 2) and Table 2 (lettuce fresh mass, dry mass, and root length, Trial 1 and Trial 2, as Mean ± SD), and Figures 1–6 (system schematics, photos, root-length box plot, a linear regression of fresh mass vs. root length, and root-condition photos). None of this content is present in the PDF.
Linked claims
- Decoupled aquaponics separates fish and plant water loops
- Aquaponic environments can outperform hydroponics for plant growth
Citations to chase
- todo Godfray et al. 2010 — cited (p.1) on food security/sustainable production drivers; check if already in vault.
- todo Pimentel et al. 2004 — cited (p.1) for the “agriculture uses 70% of global freshwater” figure [secondary, cites Pimentel et al. 2004].
- todo Maucieri et al. 2018 — cited (p.1) on aquaponics reducing fertilizer/water use.
- todo Rakocy 2012; Tyson, Treadwell et al. 2011; Goddek et al. 2015 — cited (p.1) on the dual-use-of-resources rationale for aquaponics.
- todo Blidariu & Grozea 2011 — cited (p.1) framing aquaponics as a sustainable RAS development.
- todo Engle 2015; Monsees et al. 2017; Quagrainie et al. 2018 — cited (p.1) on aquaponics’ lower productivity vs. separate RAS/hydroponic systems.
Extraction notes
Source PDF is incomplete. The file Lucas - ANALYSIS OF PLANT BIOMASS PRODUCTION COMPARING DECOUPLED AQUAPONICS AGAINST EQUIVALENT SINGLE-LOOP A (34).pdf is 11 pages: title page, ProQuest reproduction notice (ProQuest Number 28091244), abstract (pp.ii–iii), copyright page (p.iv), table of contents (pp.v–vi), list of figures (p.vii), list of tables (p.viii), acknowledgements (p.ix), and the first page of Chapter 1: Introduction (p.1, ending mid-sentence with a ProQuest “reproduced with permission… further reproduction prohibited” footer). The Table of Contents itself references content through at least p.44 (Chapter 2 Methods, Chapter 3 Results with Tables 1–2, Chapter 4 Discussion, Chapter 5 Conclusion, References, and an Appendix photo). None of that content is in this file. This looks like a ProQuest preview/sample download rather than the complete dissertation. Recommend sourcing the full text from ProQuest Dissertations & Theses Global (ProQuest Number 28091244) or the UWM institutional repository before this paper can be usefully cited for any numeric result.
⚠️ Advisor name contradiction (metadata, not a trials.csv field — does not affect quality score). Abstract (p.ii): “Under the Supervision of Professor Osvaldo J Sepulveda Villet.” Acknowledgements (p.ix): “I would like to thank my advisor Dr. Jhonatan Sepulveda Villet for taking me on as research assistant…” Same surname, different given names (“Osvaldo J” vs. “Jhonatan”), both stated as this thesis’s single advisor. Not reconcilable from the text provided — both quoted here verbatim; unresolved, verify before citing (e.g. against the UWM thesis committee page or ProQuest record). Not scored as ⚠️BLOCK/MATERIAL since it is thesis front-matter, not an extracted trial value.
WARN-MINOR System naming: Abstract and running text call the decoupled treatment the “decoupled recirculation aquaponics system (DRAPS)”; the List of Figures/Tables captions (pp.vii–viii) instead call the same system the “double recirculating aquaponic system.” Both terms clearly refer to the same treatment (contrasted with “single recirculating aquaponic system” throughout). No cell is affected — recorded using the abstract’s own defining language in System type, with both phrasings noted.
[not reported] fields, grouped: every quantitative field in trials.csv (fish identity/husbandry, all water-quality parameters, all plant growth measurements, replicate counts, statistical test details, system engineering specifics, environmental controls) is [not reported]/NR in this note and in out/lucasAnalysisPlantBiomass2020.trials.csv, because Chapters 2–5, Tables 1–2, and Figures 1–6 are absent from the available PDF. This is a single root cause (incomplete source file), not a pattern of paper-level under-reporting, so it is not evidence the extraction template needs adjusting.
Region/Country basis: Region (North America) and Country (USA) are recorded in trials.csv solely on the basis of the stated institution “The University of Wisconsin-Milwaukee” (title page, p.i) — a directly-stated fact in the PDF, not an inference from outside knowledge about the study site itself. Lat/Long are left NR: the PDF does not state coordinates for the actual grow-system location, and estimating them would require inferring a specific facility location from institution name alone, which the prime directive rules out.
Plant Category, Fish, Fish Category, System type details, Measured Unit, Statistic Details, Statistically analysed: all NR/UNCLEAR because the paper’s own categorisation and methodological language for these appear only in Chapters 2–3, not present here. Statistically analysed is recorded UNCLEAR rather than NR because the Table of Contents confirms a “2.4 Statistical Analysis” section exists (so analysis was plausibly performed) but its content, and whether it covered this specific outcome, cannot be confirmed from the available text.
Tags: Meta/Type/Experiment and Meta/Region/North-America reused from existing vault facets (per TAGS.md/CLAUDE.md conventions observed in other notes; TAGS.md was not found in the vault at extraction time, consistent with other recent batch notes). Meta/Plant/Lettuce follows the existing Meta/Plant/ facet pattern seen elsewhere in the vault (e.g. Meta/Plant/Chicory). No Meta/Fish/ tag applied — the fish species/category is never named in the accessible text, so tagging any specific fish would be a guess.
Item type judgement: classified experiment under SCHEMA.md’s decision rule (“did the authors collect data themselves?”) — the abstract, Table of Contents (Materials and Methods, Results, Statistical Analysis chapters), and stated objective (“to compare the yield of lettuce… against three systems”) are all consistent with original controlled data collection, not a synthesis of others’ work. This is a judgement based on structure/framing alone, since the chapters that would confirm replication and statistical testing are not present in the file — flagged here rather than silently assumed.
Source: Lucas - ANALYSIS OF PLANT BIOMASS PRODUCTION COMPARING DECOUPLED AQUAPONICS AGAINST EQUIVALENT SINGLE-LOOP A (34).pdf
Data Tables
Structured data extracted from this paper into the vault's
trials.csv/plant_measurements.csvdatasets. Fields the paper didn't report are omitted. Download the full datasets (measurements).
Trial Parameters
lucasAnalysisPlantBiomass2020-T1
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa) |
System & Setup
| Field | Value |
|---|---|
| System type | Single recirculating aquaponic system (SRAPS) — abstract’s own term; List of Figures/Tables captions consistently call this the ‘single recirculating aquaponic system’ (no naming conflict for this treatment) |
| Combination | Lettuce (Lactuca sativa); SRAPS vs. hydroponic control |
Site
| Field | Value |
|---|---|
| Region | North America |
| Country | USA |
Experimental Remarks: TRIAL DEFINITION: T1 = single recirculation aquaponics system (SRAPS), the traditional single-loop aquaponic treatment described in the abstract (fish and plant water share one loop). Paired control = hydroponics, recorded in the HYD columns. Compared against T2 (DRAPS) as the paper’s other aquaponic treatment. | SOURCE INCOMPLETE: this PDF is an 11-page front-matter-only excerpt (title page through p.1 of Chapter 1); Chapter 2 (Materials and Methods), Chapter 3 (Results, incl. Table 1 environmental conditions and Table 2 lettuce fresh/dry mass and root length for Trial 1 and Trial 2), Chapter 4 (Discussion), Chapter 5 (Conclusion), References, and Figures 1-6 are all absent from the file, despite being listed in the Table of Contents (through at least p.44). Every quantitative cell in this row is NR for that reason, not because the paper under-reports. | NOTE: the paper’s own Trial 1/Trial 2 (Table 1-2 captions) appear to be two sequential experimental runs in which all three systems (HYD, SRAPS, DRAPS) were each measured, distinct from this schema’s per-treatment Trial ID convention; whether Trial 1 and Trial 2 differed in design (vs. being straight replicates) cannot be determined without Chapter 2, so no attempt was made to split rows by the paper’s internal trial numbering. | Statistically analysed recorded UNCLEAR: Table of Contents confirms a 2.4 Statistical Analysis section exists, so some analysis was plausibly performed, but its content and applicability to this outcome cannot be confirmed from the available text. | Region/Country (North America/USA) recorded solely from the stated institution The University of Wisconsin-Milwaukee (title page); Lat/Long left NR as the PDF gives no coordinates and the facility’s precise location is not derivable from the institution name alone. | Remineralization recorded NR rather than N: the abstract defines DRAPS by contrast with SRAPS on this point (solid waste from fish is mineralized and sent to the hydroponic plant grow system — implying SRAPS lacks this specific step), but does not directly state SRAPS’s own solids-handling process, so NR avoids over-reading a contrastive definition as a direct statement about this treatment. | WARN-MINOR System naming: abstract/running text call the OTHER treatment decoupled recirculation aquaponics system (DRAPS); List of Figures/Tables captions instead call it double recirculating aquaponic system — see T2 remarks; no cell affected for this row.
lucasAnalysisPlantBiomass2020-T2
Plant
| Field | Value |
|---|---|
| Plant | Lettuce (Lactuca sativa) |
System & Setup
| Field | Value |
|---|---|
| System type | Decoupled recirculation aquaponics system (DRAPS), also captioned ‘double recirculating aquaponic system’ in the List of Figures/Tables (p.vii-viii) — see WARN-MINOR in remarks. Defining features per abstract: (1) solid fish waste is mineralized and sent to the hydroponic plant unit; (2) water from the hydroponic unit does not return to the fish; (3) separate aquatic environments allow independently-optimised conditions for fish and plants. |
| Remineralization | Y (Solid waste from fish is mineralized separately and routed to the hydroponic plant grow system (abstract, p.ii) — this is the treatment’s defining feature) |
| Combination | Lettuce (Lactuca sativa); DRAPS vs. hydroponic control |
Site
| Field | Value |
|---|---|
| Region | North America |
| Country | USA |
Experimental Remarks: TRIAL DEFINITION: T2 = decoupled recirculation aquaponics system (DRAPS), reengineered from SRAPS per the abstract so that (1) fish solid waste is mineralized separately before reaching the plant unit, (2) hydroponic water does not return to the fish, and (3) fish and plant environments can be independently optimised. Paired control = hydroponics, recorded in the HYD columns. Compared against T1 (SRAPS) as the paper’s other aquaponic treatment. | SOURCE INCOMPLETE: identical caveat as T1 — this PDF is an 11-page front-matter-only excerpt; Chapters 2-5, Tables 1-2, References, and Figures 1-6 are absent though listed in the Table of Contents. Every quantitative cell in this row is NR for that reason. | NOTE: same caveat as T1 regarding the paper’s internal Trial 1/Trial 2 numbering vs. this schema’s per-treatment Trial ID — not split further without Chapter 2 content. | Statistically analysed recorded UNCLEAR: see T1 remarks. | Region/Country basis: see T1 remarks (institution-derived, Lat/Long NR). | WARN-MINOR System naming: abstract and running text (p.ii-iii) consistently call this treatment the decoupled recirculation aquaponics system (DRAPS); the List of Figures caption (Figure 1, p.vii) and List of Tables captions (p.viii) instead call the same treatment the double recirculating aquaponic system. Both clearly denote the same treatment (always contrasted with the single recirculating aquaponic system); no extracted cell is affected, System type records the abstract’s defining term with both phrasings noted.