Review Reports - Difference in Energy Input and Output in Agricultural Production under Surface Irrigation and Water-Saving Irrigation: A Case Study of Kiwi Fruit in Shaanxi

Round 1

Reviewer 1 Report

The article ''Surface irrigation and water-saving irrigation resulted in the difference of energy input-output during kiwifruit production in China'' is presented for review. There are many minor and major recommendations before the article is considered for acceptance in Energies Journal. Following are the guided points for the authors to improve the article:

1. Title of the article should be re-write with respect to the research notations instead of long statement.

2. The abstract should include the problem statement specifically and there should be addition of the need of the study.

3. Some abbreviations are used without first explained. The authors should proof read it properly in the revision stage.

4. There should be some numeric figures/ statistical results / numbers in the abstract, which reflect some easy assesment of the results / outcome of the study.

5. Authors should follow the template and authors guidelines of formatting and structure of the paper with respect to the journal.

6. There should be some reference of Fig. 1 as this relates to data from somewhere.

7. Some very old literature has been used in the introduction section. Authors are advised to use no more than 3-5 years literature in general.

8. Figure 2 should be removed as this add no significance value in the article and it is very simple and can be explained in the text directly.

9. Figure 3 should be removed as well as it also add no value in the article quality and/or novality.

Author Response

Reviewer #1:

The reviewed version has improved the quality of the manuscript. Just a few points to review:

Title of the article should be re-write with respect to the research notations instead of long statement.

Response: Thank you for pointing out our mistakes. We have changed the original title to“Difference of energy input and output in agricultural production under surface irrigation and water-saving irrigation: a case study of kiwi fruit in Shaanxi”

The abstract should include the problem statement specifically and there should be addition of the need of the study.

Response：Thank you for pointing out our mistakes. we have corrected this mistake in the revised version.

Some abbreviations are used without first explained. The authors should proof read it properly in the revision stage.

Response: Thank you for pointing out this mistake，and We have corrected our mistakes in the revised edition. FAO is the abbreviation of Food and Agriculture Organization.

4.There should be some numeric figures/ statistical results / numbers in the abstract, which reflect some easy assesment of the results / outcome of the study.

Response：Thank you, we accept your comments, and we have added some numerical results to the abstract to reflect the evaluation of the study conclusions.

Authors should follow the template and authors guidelines of formatting and structure of the paper with respect to the journal.

Response: Thank you for pointing out our mistake. We have revised the format and structure of the paper according to the corresponding tips in the author's guide

There should be some reference of Fig. 1 as this relates to data from somewhere.

Response: We agree with you, and we have provided some references for Figure 1.

Some very old literature has been used in the introduction section. Authors are advised to use no more than 3-5 years literature in general.

Response: Thank you for your valuable suggestions. We have replaced those old literature in the introduction section.

Figure 2 should be removed as this add no significance value in the article and it is very simple and can be explained in the text directly.

Response: Thank you for your valuable comments. We have corrected our mistakes in the revised version.

Figure 3 should be removed as well as it also add no value in the article quality and/or novality.

Response: It’s a good suggestion and we accept it in the revised version.

Reviewer 2 Report

I carefully examined the article before recommending against publishing it in its current format. The document is titled "Surface irrigation and water-saving irrigation resulted in the difference of energy input-output during kiwifruit cultivation in China." the authors rely on survey data for their research with numerous factors that reducing the accuracy of the findings.

Author Response

Reviewer #2:

Comments and Suggestions for Authors

Response:

Thank you very much for your suggestions, and now we reply to your concerns as follows:

The reason why we carried out this research is that the input of agricultural production resources is redundant and the utilization efficiency is low, which has become an important problem limiting the healthy and sustainable development of Shaanxi kiwi industry. The key to solving this problem is to be able to understand the current situation of resource utilization efficiency. Therefore, we choose the energy input and output as the breakthrough to evaluate the energy utilization efficiency. This is a common practice for sustainable agricultural production internationally, for example, Literature 1(Ashkan Nabavi-Pelesaraei, Shahin Rafiee, et al. Modeling energy consumption and greenhouse gas emissions for kiwifruit production using artificial neural networks[J]. Journal of Cleaner Production,2016(133):924-931.) made a predictive analysis of energy input and greenhouse gas emissions of three kiwi orchards of different sizes in Iran's Guilan Province using artificial neural networks, and calculated some energy indicators, which is in great agreement with our research. The results show that the highest share of energy input in the production of kiwi fruit is the use of nitrogen fertilizer. The results of model sensitivity analysis showed that diesel fuel and nitrogen fertilizer were the most sensitive inputs for kiwifruit production and greenhouse gas emissions, reflecting the important role of nitrogen fertilizer in excessive energy consumption and greenhouse gas emissions of kiwifruit orchards; Literature 2（Pellegrini P, Roberto J. Fernández. Crop intensification, land use, and on-farm energy-use efficiency during the worldwide spread of the green revolution[J]. Proceedings of the National Academy of Sciences, 2018, 115(10):201717072.）analyzes crop yields, physical inputs and land use at the national level to assess the technological changes behind the tripling of global crop yields from 1961 to 2014. Through the transformation of machinery, fuel and fertilizer into embedded energy units, agricultural intensification measures (human subsidies per hectare) have been provided for crops in 58 countries, which account for 95% of global production. The results show that the energy input per hectare of land has greatly increased, especially in the 12 countries mainly engaged in irrigation production, no matter which continent, the growth is more prominent. Energy efficiency (crop yield/input) follows a U-shaped trajectory, starting from about 3 to nearly 4.

In order to carry out the above work, we have adopted the methods of field survey, statistical yearbook, official website data retrieval, and publicly published paper citation to obtain the required data, so as to ensure the accuracy of the data as much as possible. The above methods are relatively mature and accepted by various journals. For example, Literature 1(Mehdi, Torki-Harchegani, Rahim, et al. Almond production in Iran: An analysis of energy use efficiency (2008–2011) [J]. Renewable and Sustainable Energy Reviews, 2015.) used the method of direct questionnaire survey to analyze the input and output energy of almond production in Iran's Charmahalwalbahtiari Province from the production data of mobile almonds from farmers. The results show that electricity accounts for a large part of the input energy (50%), followed by chemical fertilizer, which is roughly consistent with our research results; Literature 2(Singh P, Singh G, Sodhi G P S. Energy auditing and optimization approach for improving energy efficiency of rice cultivation in south-western Punjab, India[J]. Energy, 2019a, 174(MAY 1):269-279.) collected production data from 40 farmers in India through face-to-face conversation, audited and analyzed them for the purpose of energy input and output, and investigated and studied India's important energy intensive grain rice to optimize the energy use in rice planting. Data envelopment analysis was used to optimize the energy of rice, and it was clarified that 20 decision making units (DMUs) were effective, while 50% were invalid. The average technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) of rice fields were 0.94, 0.97 and 0.97, respectively. The results show that if the inefficient DMU adopts the management practice of efficient DMU, the energy can be saved in 9.4 and 2170 (accounting for 0.2% and 46.9% of the total savings).

In terms of questionnaire, we designed a detailed and accurate questionnaire, and used face-to-face interviews to fill in the questionnaire to obtain data. The process was standardized and the results were clear. The energy conversion coefficients involved in this paper are quoted from similar published papers.

In addition, we compared the research results with similar international studies, such as the energy efficiency of kiwi production in Guilan and Mazandaran, Iran. The research results not only reflect the general law of energy input and output in kiwifruit production, but also show the impact of regional input differences in kiwifruit planting in Shaanxi on energy utilization efficiency, which can provide an effective reference for the establishment of regional kiwifruit sustainable development planting mode.

Reviewer 3 Report

This MS takes kiwifruit production as the research object, analyzes the energy input and output under surface irrigation and water-saving irrigation from the perspective of energy, clarifies the difference in energy utilization between surface irrigation and water-saving irrigation, and finds that in the process of agricultural production, mineral fertilizer The energy input accounted for the highest, and it was concluded that the application of water-saving irrigation technology increased the unit energy productivity by 21.6%.

This MS provides theoretical and data support for the optimization of kiwifruit high-efficiency water-saving irrigation technology mode, and optimizes a set of green and efficient production technical solutions for kiwifruit high-efficiency water-saving irrigation in Guanzhong area of Shaanxi Province. This research direction is less researched in China, and it is expected to be extended to the production practice of various crops.

Line 451: Change DNU to DMU

Line 445: Can you try to explain why the energy input of mineral fertilizers is drastically reduced, thereby reducing the energy input of water-saving irrigation?

552 stud changed to study

Section 637 Language Error. It is recommended to rearrange the expression of this sentence and use punctuation correctly.

Shaanxi Province, China is adopted as the case study. What are other feasible alternatives? What are the advantages of adopting this case study over others in this case? How will this affect the results? The authors should provide more details on this.

Kiwifruit is adopted as the focus of this study. What are other feasible alternatives? What are the advantages of adopting this species over others in this case? How will this affect the results? The authors should provide more details on this.

Water-saving irrigation is the focus of this study. What are other feasible alternatives? What are the advantages of adopting this species over others in this case? How will this affect the results? The authors should provide more details on this.

Author Response

Reviewer #3:

Line 451: Change DNU to DMU

Response: Thank you for pointing out our mistake, we have revised it.

Line 445: Can you try to explain why the energy input of mineral fertilizers is drastically reduced, thereby reducing the energy input of water-saving irrigation?

Response: Thank you for your valuable comments. This is mainly because when farmers use the water-saving irrigation system, they add small fertilizing devices in the field, realizing the precise control of fertilization in the production process and reducing the energy input of inorganic fertilizer, thus reducing the use of inorganic fertilizers may be an important way to improve the energy efficiency of kiwifruit production.

552 stud changed to study

Response: Thank you for pointing out our mistake, we have revised it.

Section 637 Language Error. It is recommended to rearrange the expression of this sentence and use punctuation correctly.

Response：We accepted your suggestion, and we have revised it. We have corrected the wrong sentence in the original as:

Large input of inorganic fertilizer and low management level of water-saving irrigation system are the main limiting factors for the sustainable production of Chinese kiwifruit at present, it is urgent to popularize the fertilization technology of scientific system, formulate the appropriate fertilizer amount and proportion, and promote the scale, unification and standardization of kiwifruit production.

Response: Allow me to say that the main reason why we choose kiwi is that the north foot of Qinling Mountains in Shaanxi Province is the eugenic area and main planting area of kiwi. As of the end of 2017, the scale and output of kiwi planting in Shaanxi Province, whether in China or the world, account for a large proportion, and it is the largest kiwi production base in the world. However, since 2016, the development of the kiwi industry in Shaanxi Province has encountered a bottleneck: affected by the cognitive limitations and use defects of farmers on the input of agricultural production factors, the kiwi production cost has increased year by year, and the production income has decreased year by year. The imbalance between input and output has seriously affected the sustainability of the development of the kiwi industry in Shaanxi, and even the destruction of gardens and abandonment of seeds have occurred. On the other hand, under the strong guidance and support of the government, kiwifruit irrigation has largely changed from traditional surface irrigation to efficient water-saving irrigation, with a significant increase in irrigation water utilization coefficient and significant benefits in fertilizer saving, yield increase and labor saving. However, the application of high efficiency water-saving irrigation technology has increased the initial investment of the irrigation system, and the increase in energy consumption and greenhouse gas emissions due to the increase in the working pressure of the system. Moreover, in the application and promotion of high-efficiency water-saving irrigation system, there are also some phenomena such as low system management and operation level and poor application effect caused by low education level of users and lack of supporting facilities. At present, the impact of the application and management level of efficient water-saving irrigation technology on the input-output efficiency of kiwifruit and the sustainability of kiwifruit production still lacks quantitative evaluation.

Response: Shaanxi is rich in crops that can be used for water-saving irrigation, such as grapes, oranges, apples, etc., which can be used as alternatives for research. However, the main reason why we adopt kiwi is that Shaanxi Province is the prepotent and main planting area of kiwi in China, and large-scale planting has been formed. With the promotion and application of water-saving irrigation technology, most planting areas have completed the upgrading of irrigation methods, from traditional flood irrigation to water-saving irrigation, but some planting areas still use traditional flood irrigation. Choosing kiwi as the research object can make our research contrast more distinct and the research results more accurate.

Response: Allow me to answer this question. At present, due to the limitation of water shortage and the promotion of agricultural modernization, water-saving irrigation has become the development direction of China's agriculture. However, the implementation of this technology is bound to change the input and output of agriculture, but there is no complete energy evaluation system to quantify and evaluate this change in China, so this is also the necessity of this study.

Round 2

Reviewer 1 Report

Author Response

Is the content succinctly described and contextualized with respect to previous and present theoretical background and empirical research (if applicable) on the topic?

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Are all the cited references relevant to the research?

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Are the research design, questions, hypotheses and methods clearly stated?

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Are the arguments and discussion of findings coherent, balanced and compelling?

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For empirical research, are the results clearly presented?

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Is the article adequately referenced?

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Are the conclusions thoroughly supported by the results presented in the article or referenced in secondary literature?

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Response：

Thank you for reviewing our manuscript in your busy schedule, and for your valuable suggestions on our manuscript. We have revised our manuscript again according to your suggestions, and the specific revised content is marked in red in the revised version.

Thank you again for your patient guidance, and wish you success in your work.