Crop Cultivation Underneath Agro-Photovoltaic Systems and Its Effects on Crop Growth, Yield, and Photosynthetic Efficiency
Round 1
Reviewer 1 Report
This study used Agro-photovoltaics (APV) to plant several crops (rice, potato, sesame, and soybean) and showed significant yield loss due to shading effect of APV. The negative impact of APV are well known and causes the limitation of the extension of this technology. What are the new findings of this article and what authors like to share?
1. L25, “The photosynthetic efficacy in rice plants grown underneath the APV systems was lower than in the control plots. These factors may “help” lower the crop yield when cultivation is underneath an APV system. “ please rewrite this sentence.
2. M&M: should elaborate more on the APV facility used in this study. For example, material, size, height…
3. All Tables and Figures should show the standard deviation of each mean & n=?
4. L295, “Figure 5. ETR of rice plants at 10 and 20 days after transplanting (DAT) underneath an agrophoto-voltaic (APV) system,…”. But these Figures showed data of “Effect of various PARs on ETR”?
5. L296, Error bars represent standard deviation. Please add n=?
6. L316, Figure 6. Soar radiation. Change to Solar radiation
7. L319, what’s the difference between Solar radiation (A), PAR (B), in Figure 7.
8. L332, One microclimate factor that is directly influenced by solar radiation is air temperature. How author make this conclusion?
9. L357, “APV systems require modifications …” could authors suggest what are “the appropriate crops” for planting under the APV system? Authors should suggest - How to reduce yield loss for APV applications?
10. This manuscript's English should be edited.
Author Response
- L25, “The photosynthetic efficacy in rice plants grown underneath the APV systems was lower than in the control plots. These factors may “help” lower the crop yield when cultivation is underneath an APV system. “ please rewrite this sentence.
Response: corrected.
- M&M: should elaborate more on the APV facility used in this study. For example, material, size, height…
Response: We added photos on APV facilities and addressed in Materials and Methods section.
- All Tables and Figures should show the standard deviation of each mean & n=?
Response: analyzed the data using a t-test.
- L295, “Figure 5. ETR of rice plants at 10 and 20 days after transplanting (DAT) underneath an agrophoto-voltaic (APV) system,…”. But these Figures showed data of “Effect of various PARs on ETR”?
Response: corrected.
- L296, Error bars represent standard deviation. Please add n=?
Response: corrected.
- L316, Figure 6. Soar radiation. Change to Solar radiation
Response: corrected.
- L319, what’s the difference between Solar radiation (A), PAR (B), in Figure 7.
Response: We mentioned in Materials and Methods section.
- L332, One microclimate factor that is directly influenced by solar radiation is air temperature. How author make this conclusion?
Response: corrected.
- L357, “APV systems require modifications …” could authors suggest what are “the appropriate crops” for planting under the APV system? Authors should suggest - How to reduce yield loss for APV applications?
Response: addressed them.
- This manuscript's English should be edited.
Response: This manuscript was edited by a native speaker (English editing company).
Reviewer 2 Report
Agro-photovoltaic is a system that allows to reconcile energy production with the cultivation of plants and food production. It is a new system and it will probably develop in the coming years. Of course, the response of plants to cultivation under a photovoltaic installation depends on the climatic conditions, type of structure, crop species and even the variety.. Therefore, I find the research presented in the manuscript very up-to-date and interesting.
However, in my opinion manuscript needs significant additions and corrections, especially the chapter 'Material and methods'. The methodology should be described in sufficient detail to allow the experiment to be repeated or its results to be compared with the results of other studies. It is also a pity that the experiments were repeated in 2022 only for potatoes. Weather conditions can significantly influence the achieved results. In field experiments, the results of one-year studies are not very reliable.
Detailed comments:
1. Table 1 shows the characteristics of the APV installation. It is not very detailed. What was the height of the installation. Could the cultivation of plants be carried out with machines normally used in the cultivation of these species? What about the rainfall? Was rainwater collected and spread across the field or did it fall from the photovoltaic panels to one place?
The authors probably have photos of experiments and installations. It is worth presenting them so that the reader can see what the constructions were.
2. Please state what was the growing area (length and width) of plants under APV, for each species and each location. And the area of control plots without APV.
3. Please provide more information about the conditions of cultivation of each species, i.e. the method of sowing and harvesting and the performance of other agrotechnical treatments (fertilization, protection against diseases, weeds and pests). NPK fertilization is given for rice only. For each species, not only the sowing date, but also the harvest date.
4. For each tested feature, the method of its determination must be described, i.e. on how many plants, how selected, and how the determination was performed. How the yield was determined.
5. Line [88] - why 20 x 100. Is this the standard spacing used in Korea for potato cultivation?
6. Line [96] - what does it mean ‘high and low-quality potatoes….’ how were they distinguished, on what basis?
7. Line [121] – is ‘….spaces on June 15, 2021, in Seungju’ - rather in Naju
8. Line [130-139] - At what date (day and month or days after planting) and at what time of the day the SPAD measurements were determined, on how many plants, as selected on which plants under APV. There is an important question of shading.
9. Line [141] - please specify here in which location these measurements are performed
10. Line [145] – In how many points in the field there are sensors for measuring air temperature and soil temperature. How was the place of their foundation chosen. This is essential for the reliability of the APV results.
11. Line [153-155] – ‘All experiments were carried out with three replications’ - what does it mean?. Was the area under the APV construction divided into three parts, and from each plant samples were taken for determination, and the yield was collected and estimated? Because there were probably not three identical structures in every location?
12. Line [159] – ‘The stem number…’ number of stems from what? from 1 plant?. As I wrote earlier, it is necessary to describe in detail how the measurements of the analyzed features were made and for each one it is necessary to specify the unit. The same is true for the number of leaves.
13. In table 2 - please enter a unit for each feature
14. Line [172] – ‘…the differences were not significantly different’- this sentence needs to be corrected (style).
15. Line [184 and 188] - I think it should be Cheongju, as shown in table 1
16. The yield of plants is better given in kg per hectare and use the exponential notation of units, i.e. kg ha-1
17. I propose the results that are given in Table 5 and in Figure 1 to present in two tables. In figure 2 it is plant height and in table 5 stem length. how is it different. how each of these features was marked - this must be described in the methodology. In addition ‘branching number’ is in table 5 and in figure 1, and these are different values.
18. I don't understand these terms: Tuber weight per hill, Capsule number per hill, Panicle number per hill. what is this unit (per hill)? Please explain this in the methodology.
19. Line [217] and table 6 – is ‘population number’ better term - plant number
20. Figure 2 - This graph needs to be corrected. Takes up a lot of space and produces few results.
21. In table 6 is ‘grain weight’ and ‘ungrained weight’ - what does it mean, how was it marked? This must be described in the methodology.
22. Table 7 - Panicle length in Seungju is 87,2?
23. Figure 3 is unnecessary, these results can be presented in Table 7. The graph shows 'plant height'. How it was determined, since the table shows the length of the stalk and the length of the panicle. So the sum is like the height of the plant? This also has to be described in the methodology.
24. Line [283-284] – ‘….the electron transport rate (ETR)’ - in the chapter 'Material and methods' it was not mentioned that the measured feature was not described and how it was done.
Author Response
- Table 1 shows the characteristics of the APV installation. It is not very detailed. What was the height of the installation. Could the cultivation of plants be carried out with machines normally used in the cultivation of these species? What about the rainfall? Was rainwater collected and spread across the field or did it fall from the photovoltaic panels to one place?
The authors probably have photos of experiments and installations. It is worth presenting them so that the reader can see what the constructions were.
Response: We addressed the height of APV systems and precipitation during the experimental period. In addition, we added the photos of APV systems.
- Please state what was the growing area (length and width) of plants under APV, for each species and each location. And the area of control plots without APV.
Response: We addressed them.
- Please provide more information about the conditions of cultivation of each species, i.e. the method of sowing and harvesting and the performance of other agrotechnical treatments (fertilization, protection against diseases, weeds and pests). NPK fertilization is given for rice only. For each species, not only the sowing date, but also the harvest date.
Response: We addressed them.
- For each tested feature, the method of its determination must be described, i.e. on how many plants, how selected, and how the determination was performed. How the yield was determined.
Response: We addressed them in Materials and Methods section.
- Line [88] - why 20 x 100. Is this the standard spacing used in Korea for potato cultivation?
Response: addressed.
- Line [96] - what does it mean ‘high and low-quality potatoes….’ how were they distinguished, on what basis?
Response: addressed.
- Line [121] – is ‘….spaces on June 15, 2021, in Seungju’ - rather in Naju
Response: corrected.
- Line [130-139] - At what date (day and month or days after planting) and at what time of the day the SPAD measurements were determined, on how many plants, as selected on which plants under APV. There is an important question of shading.
Response: corrected.
- Line [141] - please specify here in which location these measurements are performed
Response: corrected.
- Line [145] – In how many points in the field there are sensors for measuring air temperature and soil temperature. How was the place of their foundation chosen. This is essential for the reliability of the APV results.
Response: addressed.
- Line [153-155] – ‘All experiments were carried out with three replications’ - what does it mean?. Was the area under the APV construction divided into three parts, and from each plant samples were taken for determination, and the yield was collected and estimated? Because there were probably not three identical structures in every location?
Response: addressed.
- Line [159] – ‘The stem number…’ number of stems from what? from 1 plant?. As I wrote earlier, it is necessary to describe in detail how the measurements of the analyzed features were made and for each one it is necessary to specify the unit. The same is true for the number of leaves.
Response: corrected.
- In table 2 - please enter a unit for each feature
Response: corrected.
- Line [172] – ‘…the differences were not significantly different’- this sentence needs to be corrected (style).
Response: corrected.
- Line [184 and 188] - I think it should be Cheongju, as shown in table 1
Response: corrected.
- The yield of plants is better given in kg per hectare and use the exponential notation of units, i.e. kg ha-1
Response: corrected.
- I propose the results that are given in Table 5 and in Figure 1 to present in two tables. In figure 2 it is plant height and in table 5 stem length. how is it different. how each of these features was marked - this must be described in the methodology. In addition ‘branching number’ is in table 5 and in figure 1, and these are different values.
Response: corrected.
- I don't understand these terms: Tuber weight per hill, Capsule number per hill, Panicle number per hill. what is this unit (per hill)? Please explain this in the methodology.
Response: corrected.
- Line [217] and table 6 – is ‘population number’ better term - plant number
Response: corrected.
- Figure 2 - This graph needs to be corrected. Takes up a lot of space and produces few results.
Response: corrected.
- In table 6 is ‘grain weight’ and ‘ungrained weight’ - what does it mean, how was it marked? This must be described in the methodology.
Response: corrected.
- Table 7 - Panicle length in Seungju is 87,2?
Response: corrected.
- Figure 3 is unnecessary, these results can be presented in Table 7. The graph shows 'plant height'. How it was determined, since the table shows the length of the stalk and the length of the panicle. So the sum is like the height of the plant? This also has to be described in the methodology.
Response: corrected. We measured plant height and tiller number at early stages (39-44 days after transplanting) in figure 3. However, parameters in table 7 were recorded at harvest.
- Line [283-284] – ‘….the electron transport rate (ETR)’ - in the chapter 'Material and methods' it was not mentioned that the measured feature was not described and how it was done.
Response: We added the ETR in Materials and Methods section.
