Improving Hill Farming: From Maize Monocropping to Alternative Cropping Systems in the Thai Highlands
Round 1
Reviewer 1 Report
The manuscript's topic aligns with the sensitive and current thematic of environmental sustainability safeguard. This topic has been introduced clearly both in the abstract and introduction. An extensive and fitting bibliography has been studied.
The authors have been promoted the land conversion into the Hill Pond Rice System (HPRS) in four provinces of Northern Thailand. All land conversion factors are analysed to understand better the benefits of this farming system and its sustainable farming practices. Statistical analyses based on the double-hurdle and Tobit techniques has resulted solid and consistent.
Finally, though the article describes a regional case study, it can also be helpful and exciting for other contexts where agricultural intensification has led to the depletion and degradation of soil resources
Author Response
Comment 1-1
The manuscript's topic aligns with the sensitive and current thematic of environmental sustainability safeguard. This topic has been introduced clearly both in the abstract and introduction. An extensive and fitting bibliography has been studied.
Response 1-1
Thank you very much for your time spent reviewing our manuscript.
Comment 1-2
The authors have been promoted the land conversion into the Hill Pond Rice System (HPRS) in four provinces of Northern Thailand. All land conversion factors are analysed to understand better the benefits of this farming system and its sustainable farming practices. Statistical analyses based on the double-hurdle and Tobit techniques has resulted solid and consistent.
Response 1-2
Thank you for highlighting the potential contribution of our manuscript.
Comment 1-3
Finally, though the article describes a regional case study, it can also be helpful and exciting for other contexts where agricultural intensification has led to the depletion and degradation of soil resources.
Response 1-3
We totally agree on the external validity of our findings to other areas facing similar issues of agricultural intensification.
Reviewer 2 Report
Comments by line
Title: there is no real evidence of sustainable farming or true agroecology in the paper; hence a change in the title is proposed: Improving Hill Farming: From Maize Monocropping to improved cropping systems in the Thai Highlands
41: pls. correct: monocropping increases more than anything else problems of pests, diseases and weeds and hence a higher use of pesticides. Problems of soil degradation and erosion, disruption of the natural composition of the soil, and groundwater pollution and eutrophication in the surrounding ecosystems are exclusively due to mechanical soil tillage, which is the underlying cause of ecosystem degradation, which is only worsened with monocultures.
61: the term “SAP” is questionable, since no isolated practice can lead to sustainability. Those practices also may at the most be less unsustainable, but not “more sustainable”. These terms should be changed, for example into improved agricultural practices. The term minimum tillage is not useful as SAP, since it includes tillage, which per se is NOT SUSTAINABLE, while the term itself is not defined, i.e. the degree of tillage is not specified. In line 57 you refer to one of the principles of Conservation Agriculture as minimum soil disturbance, which is the correct term for a sustainable system. Pls. revise the paper for these details.
70: these systems are presumably tillage based, which is the cause for the problems. If it is so, pls. mention this as the core problem.
112: the mentioned system cannot be called sustainable; hence the use of that term should be limited, replacing it with “improved farming practices”.
261: pls. see above comment on the sustainability of the listed SAPs, in particular minimum tillage; pls. adjust the wording.
394/395: The type of shocks listed would typically have different coefficients and should therefore have been better specified: while drought and flood typically encourage to adopt improved practices, particularly climate smart agriculture, other more personal shocks like death and illness might discourage the adoption of any change. Pls. explain.
543/659: chapters discussion and conclusion: it might be worth in the discussion to reflect on the impact of the eventual implementation of the HPRS on the environment. Some of them have less impact than others, not all are necessary to achieve positive impact and none of them guarantees sustainability in farming, as, for example, Conservation Agriculture with only three principles: minimum soil disturbance, mulch cover, crop diversity. These three are essential for sustainability, other improved practices and techniques can be added for additional benefits in productivity and sustainability. By offering the farmers with the HPRS a very complex set of practices without specifying, which ones are essential and which are complementary, the farmers might be overwhelmed, as rightly discussed in the paper. I would suggest to add this aspect and point of view to the discussion and to the conclusion, since it would have significant relevance for policies.
Author Response
Comment 2-1
Title: there is no real evidence of sustainable farming or true agroecology in the paper; hence a change in the title is proposed: Improving Hill Farming: From Maize Monocropping to Improved Cropping Systems in the Thai Highlands
Response 2-1
Thank you for your valid suggestion. Incorporating your point, the title has been revised as follows:
Improving Hill Farming: From Maize Monocropping to Alternative Cropping Systems in the Thai Highlands
Comment 2-2
41: Pls correct: monocropping increases more than anything else problems of pests, diseases and weeds and hence a higher use of pesticides. Problems of soil degradation and erosion, disruption of the natural composition of the soil, and groundwater pollution and eutrophication in the surrounding ecosystems are exclusively due to mechanical soil tillage, which is the underlying cause of ecosystem degradation, which is only worsened with monocultures.
Response 2-2
We agree and have incorporated your point into the second paragraph of Section 1 as follows:
"However, the changes in cropping patterns and production practices in favor of intensive monocropping systems gave rise to outbreaks of pests, weed, and plant dis-eases, which were treated with increased use of external chemicals. The intensive use of pesticides poses a health threat to both farmers and consumers, as well as disruption to ecosystems [4, 5, 9–12]. Moreover, repeated cultivation of the same crop in the same parcels results in extraction of particular nutrients from soil, leading to in-tensive use of synthetic fertilizer to compensate for the nutrient loss [13–16]. Therefore, intensive monocropping practices create negative externalities when these agrochemicals eventually make their way into groundwater or become airborne pollutants, affecting the surrounding environments [17–19]. Moreover, use of mechanical soil tillage disrupts the natural composition of soil and causes soil erosion, compaction, nutrient runoff, groundwater pollution and eutrophication, and biodiversity loss, which is the underlying cause of ecosystem degradation [20–23]."
(Lines 36-48)
Comment 2-3
61: the term “SAP” is questionable, since no isolated practice can lead to sustainability. Those practices also may at the most be less unsustainable, but not “more sustainable”. These terms should be changed, for example into improved agricultural practices.
The term minimum tillage is not useful as SAP, since it includes tillage, which per se is NOT SUSTAINABLE, while the term itself is not defined, i.e. the degree of tillage is not specified.
In line 57 you refer to one of the principles of Conservation Agriculture as minimum soil disturbance, which is the correct term for a sustainable system. Pls. revise the paper for these details.
Response 2-3
Thanks for your insight. Accordingly, the term SAP has been replaced by “improved farming practices” or “improved agricultural practices” throughout the manuscript. Likewise, farming systems consisting of those improved practices are now referred to as “alternative farming systems” or “improved farming systems”. We have deleted the term “minimum tillage” and stopped attaching the word “sustainable” whenever tillage is involved.
Below are some examples of the replacement of SAP and minimum tillage.
“Other improved farming practices include organic agriculture, minimum use of syn-thetic fertilizer, crop rotation, multiple cropping, crop-livestock integration, and agroforestry, among other things [15, 36–43].”
(Lines 61-63)
“a set of alternative farming systems encompassing organic farming, natural farming, integrated farming, New Theory farming, and agroforestry systems have been introduced to rural farmers in Thailand in various manners [49–51].”
(Lines 77-80)
“The Hill-Pond-Rice-System (HPRS) has been promoted as an alternative to the intensive and unsustainable maize monocropping with mechanical soil disturbance, especially in the upland areas that have strategic head waters of Thailand. The implementation of the HPRS is expected to restore forest, soil, and water resources that have been degraded due to the intensive applications of tillage and synthetic inputs.”
(Lines 689-693)
Similar corrections along those lines have been made throughout the manuscript and are highlighted in color.
Comment 2-4
70: these systems are presumably tillage based, which is the cause for the problems. If it is so, pls. mention this as the core problem.
Response 2-4
Incorporating your point, we have mentioned that the system involves tillage and emphasized the issue, as follows:
“Much of the northern region lies in the mountainous landscape, where intensive monocropping agriculture occupies large part of the forest areas, particularly maize (Zea mays. L.) production for fodder markets [11, 46], which typically entails mechanical soil tillage [47]. As these areas are located in the upstream of major rivers, the degradation of soil and water resources has adversely affected the livelihoods of the downstream population as well, adding to the externalities [48].”
(Lines 69-75)
Comment 2-5
112: the mentioned system cannot be called sustainable; hence the use of that term should be limited, replacing it with “improved farming practices”.
Response 2-5
We agree and the said sentence has been revised as follows:
“Better understanding of the farm-level determinants of conversion of current farming systems into the HPRS would contribute to improving the policy design for dissemination of the alternative farming practices.”
(Lines 112-114)
Comment 2-6
261: pls. see above comment on the sustainability of the listed SAPs, in particular minimum tillage; pls. adjust the wording.
Response 2-6
We agree and have corrected the terms SAP and minimum tillage along the lines of your comment, as follows:
“Conversely, male plot managers were more likely to adopt improved farming practices than female managers (e.g., minimum soil disturbance, improved forage technologies) [75, 88, 89].”
(Lines 262-264)
Comment 2-7
394/395: The type of shocks listed would typically have different coefficients and should therefore have been better specified: while drought and flood typically encourage to adopt improved practices, particularly climate smart agriculture, other more personal shocks like death and illness might discourage the adoption of any change. Pls. explain.
Response 2-7
Thank you for your suggestion. We totally agree. Climate-related shocks (variability of rainfall, extreme climate hazards, drought or flood) could encourage the adopt of improved technologies, while personal shocks would hinder the adoption.
The revised explanation of the expected sign of the coefficient has been provided as follows:
“Experience with negative shocks is regarded as a key determinant of input use, in-vestment, and adoption of improved farming practices [74,123–126]. However, the effects can go both ways. On one hand, extreme climatic hazards (e.g., drought, flood) typically encourage the adoption of improved practices, such as climate smart agriculture [127,128]. On the other hand, idiosyncratic shocks such as illnesses discourage investment in technology [125]. Therefore, this variable is hypothesized to have either a positive or negative coefficient.”
(Lines 398-404)
Table 2 has been revised as well.
Comment 2-8
543/659: chapters discussion and conclusion: it might be worth in the discussion to reflect on the impact of the eventual implementation of the HPRS on the environment. Some of them have less impact than others, not all are necessary to achieve positive impact and none of them guarantees sustainability in farming, as, for example, Conservation Agriculture with only three principles: minimum soil disturbance, mulch cover, crop diversity. These three are essential for sustainability, other improved practices and techniques can be added for additional benefits in productivity and sustainability.
By offering the farmers with the HPRS a very complex set of practices without specifying, which ones are essential and which are complementary, the farmers might be overwhelmed, as rightly discussed in the paper.
I would suggest to add this aspect and point of view to the discussion and to the conclusion, since it would have significant relevance for policies.
Response 2-8
Thanks for the constructive suggestion. We agree that there are both positive and negative potential impacts of HPRS implementation, which is worth discussing. As per your suggestion, the essential practices and complementary practices are explicitly discussed in the discussion and the conclusion section.
The revised text is as follows:
“The set of 25 designated practices under the HPRS are intended for conservation of water and soil resources as well as for household consumption of organic rice. Yet, not all the practices should be given equal weights, and there should be some prioritization and distinction. First, excavation of a water reservoir is one of the core practices, to which construction of crooked canals, check dams, and small swamps along the canals is complementary practices to support water transportation to agricultural plots. Earth hill building can be optional since soil from the excavated reservoirs is left over into cropland. Second, soil surface cover such as mulching and ground cover plantation (e.g., vetiver grass, leguminous crops) is another core practice [150], to which application of nutrients into soil is complementary whilst zero burning and zero agrochemicals are optional. Third, organic cultivation of rice and other staple crops is another core practice, which supports food and nutrition security for households. Fruit and long-life trees can be optional for increased food security. Fourth, crop rotation and diversity are another set of core practices, which contributes to soil nutrient management and suppression of pests [151]. Other practices such as seed conservation, labor sharing, and knowledge sharing are complementary to the core practices. On the other hand, construction of water management systems and land preparation involving tillage may disturb soil properties and affect the ecosystems in the long run [150].”
(Lines 670-687)
and
“Second, not all the 25 designated HPRS practices are guaranteed to result in favorable or intended changes in the production environments and natural resources. As this article focused on the identification of factors associated with HPRS adoption, ex-post assessment of the environmental, social, and economic impacts of the HPRS is beyond the scope of the study, which would be left to another article.”
(Lines 721-725)
