An Appraisal of the Constraints, Opportunities, and Farmers’ Needs and Preferences of Oil Palm for Sustainable Production and Improvement in Tanzania

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I have read your work and I find two aspects to be very contrasting. On the positive side, the proposed methodology is well-motivated, the sample for analysis is defined and multiple analyses are proposed, which give solidity to the results obtained. In this respect, I find that the analyses are proposed and discussed in an accurate manner. So, very good. The negative side concerns the following aspects:
1. abstract - indicate the main results of your work
2. introduction - the literature review is weak and not well motivated. Strengthen the concept of sustainability and try to define the novelty of the work
3. discussion - it turns out to be very long, but I believe that you did not go into depth on the comparison with the existing literature. How does this work support the three dimensions of sustainability?
4. general - I find that the work has several typos so try to review all the work
5. conclusions - highlight the limitations of the work and indicate the main implications of your work without being redundant
6. references - I ask you to check recent works 2024-2025 published in top journals that motivate the choices of the African continent that should be supported. 

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.

Comment 1. abstract - indicate the main results of your work.

Response 1: Thank you for your comment. The main results of our work are outlined in the abstract, specifically between lines 25 and 23. We hope this has adequately addressed your concerns.

Comment 2: introduction - the literature review is weak and not well motivated. Strengthen the concept of sustainability and try to define the novelty of the work.

Response 2: Thank you for your valuable comment. We have strengthened the literature review, enhanced the discussion on the concept of sustainability, and clarified the novelty of the study.

Comment 3: discussion - it turns out to be very long, but I believe that you did not go into depth on the comparison with the existing literature. How does this work support the three dimensions of sustainability?

Response 3: Thank you for your insightful comment. We have improved some sections to provide a more comprehensive comparison with the existing literature, addressing key studies and highlighting where our findings align or contrast. Furthermore, we have explicitly articulated how our work contributes to the sustainability frameworks.

Comment 4: general - I find that the work has several typos so try to review all the work.

Response 4: Thank you for pointing this out. We have thoroughly reviewed the manuscript and corrected all identified typos. We appreciate your attention to detail.

Comment 5: conclusions - highlight the limitations of the work and indicate the main implications of your work without being redundant

Response 5: Thank you for your valuable feedback. We have added a discussion of the limitations of the study and have clarified the main implications of our work, ensuring that the content is concise and avoids redundancy. It reads as follow; -

The study primarily focused on diagnosing the constraints, opportunities and farmers' needs and preferences of oil palm for sustainable production and improvement in Tanzania. It emphasized access to improved and quality seedlings, seedlings supply systems  across broader value chains, such as the establishment of seedling nurseries and plantations, marketing and processing, which could also influence the future of oil palm production in Tanzania. The identified limitations suggest areas for further research and development. Also, there is a need for  a quantitative analysis of the diagnosed constraints to guide policies and for impact  in the oil palm industry.

  
Comments 6: references - I ask you to check recent works 2024-2025 published in top journals that motivate the choices of the African continent that should be supported. 

Response 6: Thank you for your observation. We have carefully reviewed the existing literature, but we acknowledge that there is a lack of recent literature from 2024-2025 on certain points. At this point we have ensured that the references used are the most recent and pertinent to the topic. We hope this still provides a solid foundation for supporting the focus of our study on the African continent.

Reviewer 2 Report

Comments and Suggestions for Authors

• Clarify the Study’s Purpose: The abstract should clearly state the study’s goal and why it matters and it should outline briefly the study’s methodology, including data analysis techniques.
• Regarding the Introduction: Avoid repeating background details, the authors should highlight  the specific research gap that  the study aims to address.
• Site Selection Lacks Justification: The manuscript doesn’t provide any data on oil palm production in other districts of Kigoma or compare them. If the authors had included figures showing that the selected districts have the highest production levels in the region, it would have made their choice more clear and well-supported.
• Regarding  Sampling Strategy, it Needs More Explanation: The study uses the probability proportional to size (PPS) method but does not clarify why this method was chosen over alternatives like stratified or cluster sampling. It’s unclear how missing data or non-responses were handled, which could impact the study’s accuracy.
• The calculation of 380 respondents is shown, but the final sample size is 392. The study does not explain this discrepancy.

• Data Collection Process Lacks Detail: The study mentions using semi-structured questionnaires but does not specify:

• What themes were covered.
• Whether the questionnaire was validated.

• Missing Ethical Considerations: Has the study involved direct interaction with farmers such as survey? or has used publicly available data? in the first case ethical approval is recommended to ensure informed consent and protect participants' rights
• Data Analysis Needs More Depth: The description of descriptive statistics is vague—there is no mention of inferential analysis or control for confounding variables.
• education impact: Does lower education impact farming techniques, technology adoption, or productivity?
• Limited Analysis of Farming Experience and Age: the authors said that the average age of farmers (56 years) but the study does not discuss how these factors affect innovation, sustainability, or technology adoption, because at this age the farmers are may be less likely to adopt new techniques.
•  

• It is unclear whether younger generations are interested in oil palm farming, which could impact the sector’s future.
• Farm Size and Tree Density Issues:  The study does not examine the effects of this on yield, soil health, or disease susceptibility, but it does report an average landholding of 1.45 hectares and a tree density of 153 trees per hectare, which is higher than advised planting patterns.
• Weak Economic Justifications: The reported income from oil palm (2.8 million TZS) is presented without context. How does this compare to income from other crops or national poverty thresholds?
• Constraints Are Listed Without Critical Analysis: The study has detected several challenges, such as lack of improved seedlings and poor market access, but it does not assess which issues have the most significant impact

Author Response

Thank you very much for taking the time to review our manuscript. Please find the detailed point- by- point responses below and the corresponding revisions in track changes in the revised manuscript.

Comment 1: Clarify the Study’s Purpose: The abstract should clearly state the study’s goal and why it matters and it should outline briefly the study’s methodology, including data analysis techniques.

Response 1: Thank you for your valuable comment. The goals of the study, the methodology, and the data analysis techniques have been clearly added to the abstract to provide a more comprehensive overview of the study and its significance.

Comment 2: Regarding the Introduction: Avoid repeating background details, the authors should highlight the specific research gap that the study aims to address.

Response 2: Thank you for your comment. We have addressed the repetition of background information in the introduction and have revised it accordingly. Additionally, we have clearly highlighted the specific research gap that this study aims to address.

Comment 3: Site Selection Lacks Justification: The manuscript doesn’t provide any data on oil palm production in other districts of Kigoma or compare them. If the authors had included figures showing that the selected districts have the highest production levels in the region, it would have made their choice more clear and well-supported.

Response 3: Thank you so much for the valuable comment: A Table showing production of oil palm in the region for 2023/24 season has been added for justification of the study area.

Comment 4: Regarding Sampling Strategy, it Needs More Explanation: The study uses the probability proportional to size (PPS) method but does not clarify why this method was chosen over alternatives like stratified or cluster sampling.

Response 4: Thank you for your comment. In this study, we used Probability Proportional to Size (PPS) sampling method over alternatives like cluster sampling and stratified sampling due to the significant variability in sample sizes within clusters. Specifically, in the three districts (Kigoma Rural, Kigoma Urban, and Uvinza), there is considerable variation in the number of farmers, which makes the PPS method more appropriate. PPS ensures that larger production area (Kigoma Rural) are adequately represented while still accounting for the variability in the cluster sizes.

Comment 5: It’s unclear how missing data or non-responses were handled, which could impact the study’s accuracy.

Response 5: Thank you: A total of 399 participants were invited to the study, and 392 ultimately participated, resulting in a 1.75% missing data rate, which was random. Given the low percentage of non-response, no significant bias was anticipated in the results. Therefore, the list-wise deletion method was employed to handle the non-response data, where cases with missing values were excluded from the analysis.

Comment 6: The calculation of 380 respondents is shown, but the final sample size is 392. The study does not explain this discrepancy.

Response 6: Thank you for your observation, we have improved in our manuscript as follow; -

From the determined sample size (380), 5% were added to cater for the non-responses, as proposed by Krejcie and Morgan (1970), making a sample size of 399. During data collection, the sample size covered was 392 smallholder oil palm farmers, resulting in a 1.75% missing data rate. Given the low percentage of non-response, no significant bias was expected in the results.

Comment 7: Data Collection Process Lacks Detail: The study mentions using semi-structured questionnaires but does not specify:

1. What themes were covered.
2. Whether the questionnaire was validated.

Response 7:

(i) Themes Covered in the Semi-Structured Questionnaires: We apologize for the lack of details in the original manuscript. The semi-structured questionnaires were designed to cover the following key themes: [socio-economic status of the households, demographic information, production constraints, crop management practices, access to resources and farmers’ perceptions and preferences (stated in lines 230 to 232).

(ii) Validation of the Questionnaire: Regarding the validation of the questionnaire, we acknowledge that we did not initially include information on this. To ensure the reliability and validity of the instrument, the questionnaire was validated through questionnaire pre-testing with a small sample in Mwandiga and Kiganza villages. A more detailed description of this validation process is added in the revised manuscript (lines 228 to 230).

Comment 8: Missing Ethical Considerations: Has the study involved direct interaction with farmers, such as surveys? or has used publicly available data? in the first case ethical approval is recommended to ensure informed consent and protect participants' rights

Response 8: Thank you for your valuable feedback. We would like to clarify that ethical approval was not applicable in the study area, as the study did not involve sensitive or personal data that would typically require formal ethical review. Specifically, the study involved collection of data based on general agricultural practices, which does not fall under the categories that require ethical approval in this context. However, we fully understand the importance of ethical considerations, especially when human participants are involved. We took all necessary steps to ensure that participants' rights were respected and that the data collection was conducted in a responsible manner. We also ensured that any interactions with participants were voluntary and transparent, with appropriate consent obtained. Moving forward, we will ensure that we review and adhere to ethical guidelines for any future research involving human participants, and seek ethical approval where required.

Comment 9: Data Analysis Needs More Depth: The description of descriptive statistics is vague—there is no mention of inferential analysis or control for confounding variables.

Response 9: Thank you for the valuable comment: In our study, data analysis involved descriptive statistics, including frequencies and percentages, and chi-square tests to examine associations between categorical variables. Due to the nature of the study and the research design, no explicit methods were employed to control for potential confounding variables. However, the variables of interest were carefully selected based on their relevance to the research question, and the chi-square analysis was considered appropriate for the study's objectives. For future studies, we will consider more advanced methods, such as multivariable regression, to better account for potential confounders.

Comment 10: education impact: Does lower education impact farming techniques, technology adoption, or productivity?

Response 10: Thank you for your question. Education impact was not analyzed directly in our study however our findings revealed that a significant portion of participants (80%) had only attained primary education, indicating a low level of education. Existing literature suggests that lower education levels are often linked to a reduced likelihood of adopting advanced farming techniques and technologies, which can lead to lower productivity. We have incorporated additional explanations in the revised manuscript to support this point further.

Comment 11: Limited Analysis of Farming Experience and Age: the authors said that the average age of farmers (56 years) but the study does not discuss how these factors affect innovation, sustainability, or technology adoption, because at this age the farmers are may be less likely to adopt new techniques.

Response 11: Thank you for your comment. In our study, we found that 95.6% of participants were adults above 35 years old, indicating they had experience with oil palm cultivation. While we did not directly analyze age and experience's impact on technology adoption, existing literature suggests that older and more experienced farmers may be less inclined to adopt new technologies. We have now included a discussion to reflect this insight.

Comment 12: It is unclear whether younger generations are interested in oil palm farming, which could impact the sector’s future.

Response 12: Thank you for your comment. While this study did not directly explore the interest of younger generations in oil palm farming, the age-related factors regarding technology adoption suggest that younger farmers tend to be more open to taking risks and are generally more willing to adopt new technologies compared to older farmers. We have clarified this point in the revised manuscript (lines 479 to 484).

Comment 13: Farm Size and Tree Density Issues:  The study does not examine the effects of this on yield, soil health, or disease susceptibility, but it does report an average landholding of 1.45 hectares and a tree density of 153 trees per hectare, which is higher than advised planting patterns.

Response 13: Thank you for your valuable feedback. The effects of farm size and tree density on yield, soil health, and disease susceptibility were not directly measured in this study, but we have added a discussion in the revised manuscript highlighting these potential impacts. We acknowledge the importance of these factors and suggest that future research could explore them more thoroughly to better understand their influence on oil palm production.

Comment 14: Weak Economic Justifications: The reported income from oil palm (2.8 million TZS) is presented without context. How does this compare to income from other crops or national poverty thresholds?

Response 14: Thank you for your valuable feedback. We have revised the manuscript to include additional context regarding the reported income from oil palm (2.8 million TZS). Specifically, we compared income from other crops/activities in the region and positioned it against national poverty thresholds to offer a more explicit economic justification.

Comment 15: Constraints Are Listed Without Critical Analysis: The study has detected several challenges, such as lack of improved seedlings and poor market access, but it does not assess which issues have the most significant impact.

Response 15: Thank you for your feedback. In the revised manuscript, the constraints have been further elaborated to provide a critical analysis, highlighting which issues have the most significant impact on oil palm production. This will help to better understand the relative importance of each challenge.

Reviewer 3 Report

Comments and Suggestions for Authors

1. In the introduction, the research significance of Oil palm production systems (distribution, yield, profit, existing issues, etc.) and the current status should be emphasized. The current content is somewhat scattered.
2. Please add one or more scientific questions to this paper.
3. The typicality of the selected study area can be further elaborated, including its yield, ecosystem issues, and contributions to the overall system, as the current introduction is relatively brief.
4. In Figure 1, it is recommended to use more contrasting colors to differentiate between the Kigoma Region and the study area.
5. What are the main contents of the questionnaire? It is recommended to introduce them in the paper.
6. It is suggested to separate the results and discussion, such as in Section 3.5 starting from line 316.
7. Can the conclusions be written more shorter?

Author Response

Thank you very much for taking the time to review our manuscript. Please find the detailed responses below and the corresponding revisions in track changes in the revised manuscript.

Comment 1: In the introduction, the research significance of Oil palm production systems (distribution, yield, profit, existing issues, etc.) and the current status should be emphasized. The current content is somewhat scattered.

Response 1: Thank you for your feedback. In response, we have revised the introduction to better emphasize the research significance of oil palm production systems, including aspects such as distribution, yield, profitability, and existing issues. The content has been reorganized to provide a clearer and more focused overview of our study.

Comment 2: Please add one or more scientific questions to this paper.

Response 2: Thank you for the suggestion. The research question has been added in the revised version of our manuscript.

Comment 3: The typicality of the selected study area can be further elaborated, including its yield, ecosystem issues, and contributions to the overall system, as the current introduction is relatively brief.

Response 3: Thank you for the suggestion. A Table with production statistics has been added to provide further elaboration on the typicality of the selected study area, including its yield and contributions to the overall system.

Comment 4: In Figure 1, it is recommended to use more contrasting colors to differentiate between the Kigoma Region and the study area.

Response 4; Thank you for the recommendation. The map has been updated with more contrasting colours to better differentiate between the Kigoma Region and the study area.

Comment 5: What are the main contents of the questionnaire? It is recommended to introduce them in the paper.

Response 5: Thank you for the suggestion. The contents of the questionnaire have been added in the revised version of the paper.

Comment 6: It is suggested to separate the results and discussion, such as in Section 3.5 starting from line 316.

Response 6: Thank you for the suggestion. The results have been separated from the discussion as recommended.

Comment 7: Can the conclusions be written shorter?

Response 7: Thank you for your valuable feedback. The conclusion has been revised and summarized accordingly.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

All comments are well addressed.

Reviewer 2 Report

Comments and Suggestions for Authors

All the raised issues were addressed properly.