Comparison of Land Suitability Evaluation Methods for Development Plan of Orange and Tea Trees in Western Nghe An, Vietnam45230

Comparison of Land Suitability Evaluation Methods for Development Plan of Orange and Tea Trees in Western Nghe An, Vietnam Ha Nguyen Manh1*, Tuan Nguyen Thanh2, Ngoc Hoang Thi Huyen1, Dung Bui Quang1, Huong Vu Thi Thu1 (1) VAST Institute of Geography, Hanoi, Vietnam VAST Vietnam National Museum of Nature, Hanoi, Vietnam *Coresspondence: havdl72@gmail.com (2) Abstract: Conflicts of agricultural land use and the problem of stabilizing specialized cropland areas for sustainable development of the mountainous economy can be improved through appropriate land assessment to identify potentials and limitations A number of land assessment methods have been applied in Vietnam, each has its certain advantages and disadvantages when applied to each specific case This study was conducted to compare and verify the results of two ALES and LSE methods in determining the appropriate area for orange trees and tea trees in Western Nghe An, Vietnam 15 ecological criteria were used in assessing soil for orange cultivation and 10 criteria for evaluating land for tea cultivation, divided into parameters: parameters of climate, parameters of topography and parameters of soil The study results show that: if the evaluation process of ALES is robust in terms of the limiting factors, the evaluation process of LSE by GIS-MCA platform proved to be superior in determining define larger areas of relevance Finally, the comprehensive adaptation assessment is a combination of criteria: ecological criteria, environmental criteria and socioeconomic criteria The results indicate that 64,505.9 (4.69%) in Western Nghe An area a suitable for orange cultivation and 69,388.8 (5.05%) are very suitable for tea cultivation Thus, the intentions of planning and expanding the orange-specialized and tea-specialized areas can be fully met on the very appropriate land areas Keywords: Land suitability; LSE software; Western Nghe An; Vietnam Introduction Mountain agriculture has always played an important role in enhancing food security and environmental sustainability in many countries around the world (Roozitalab et al., 2013) The mountainous area is rich in biodiversity, however also a region with a high concentration of poor people with the most unfavored living conditions and livelihoods in the world Therefore, sustainable mountainous development has been receiving more attention than ever Mountainous terrain occupies three quaters of Vietnam's land where a number of large rivers are originated (Quy, 1995) The mountainous region of Vietnam has many advantages to develop agricultural productions such as forestry, perennial crops, fruit trees, medicinal plants and livestock Despite of the great potentials, agricultural development are facing substantial constraints Therefore, the Government of Vietnam has made efforts towards policies, schemes and programs for socio-economic development of mountainous areas (VG, 2016, 2017) One of the most disadvantaged mountainous areas of Vietnam is Western Nghe An The economy in the Western Nghe An predominantly depends on agricultural The land use structure is predominantly agricultural land 177,699 of agricultural production land account for 12.9% of the whole area and 1,073,521 of forestry land accounts for 78.18% While, the total value of agricultural production is only approximately 16,647,682 million VND in 2017 (NASO, 2018) In 2017, the average product value obtained per hectare of the cultivated land of Western Nghe An is low, 53.34 million VND The average number of Nghe An is 71.04 million VND, the average of Vietnam is 85.4 million dong Particularly, the value of products obtained on of very low cultivated land in some districts such as Ky Son (16.26 million VND), Tuong Duong (21.11 million VND), and Que Phong (40.99 million VND) (NASO, 2018) The exploitation and use of agricultural land in the region is significantly not effective Currently, 99/217 communes in the region (about 45.6%) are benefited under Program 135 The large area of hills and mountains of the Western Nghe An region provides development opportunities to local agriculture, especially trees growing such as fruit trees and perennial crops To date, land are barely used for this purpose, most of the agricultural land used for low-value crops, which easily grow in lowland areas Approximately 107,641 (60.6%) of agricultural land is occupied by food crops and annual crops such as rice, maize, cassava, sweet potatoes, peanuts, sesame and sugarcane Perennial crops such as rubber, tea, coffee and fruit trees including orange, mango, pineapple and longan, are grown on approximately 70,058 (39.4% of the area) (NASO, 2018) Orange and Tea are two of the 10 major agricultural products, which have been focused on development in order to establish a large-scale production area, concentrating high-yield orange, specialty tea varieties of the province Nghe An as well as the Western Nghe An (PCNAP, 2016b) Orange trees were first planted in the late 19th century, then it has been developed to the famous orange areas such as Xa Doai and Bai Phu Oranges have become local specialties with geographical indications "Cam Vinh" established in 2007 The orange growing area in 2017 of the Western Nghe An is 4,872 (accounting for 87.2% of the whole orange growing area of Nghe An) Orange trees are grown mainly in Quy Hop (2,661 ha), Nghia Dan (1,035 ha), Thanh Chuong (388 ha), Con Cuong (361 ha), mainly traditional orange varieties Xa Doai and Van Du The growing area for commerical products is 2,060 with a total output of 32,087 tons (NASO, 2018) The Western Nghe An is also the oldest fresh tea area of Vietnam (Quy, 2003) It is an andvantage to be invested in intensive farming, expanding the area, developing into an commercial products for export Tea plays an important role in poverty reduction and livelihood improvement to mountainous residents in the Western Nghe An The commercial growing area is 7,134 ha, of which the productive area is 6,054 ha, with a total output of 69,062 tons (NASO, 2018) The districts with large tea growing areas are: Thanh Chuong (4,317 ha), Anh Son (1,834 ha), Con Cuong (380 ha) Orange and tea cultivation in Western Nghe An is facing a number of challenges Farming areas are scattered; many of them are not under controlled that results in low production efficiency, outbreak of pests and diseases, and unstable product quality It leads to conflicts between different types of land use in the region Land us is neccessarily planned in accordance with the potential and natural advantages of the region as well as farming practices, the farmers' production demand is a premise for agricultural development and stability It can barely take up references from studies on land evaluation in the Western Nghe An and district level with the assessment objects being grouped into agricultural and forestry crops; for example (Khang, 1999; Hong, 2017) These results not seem sufficient to provide a scientific basis for the potentials or limitations of land or to support land use plans As a result, local people and local government have been confused in allocating land for high-value crops production for many years Land evaluation is always considered a core component of land use planning (FAO, 1993; Baja et al., 2007; Singha and Swain, 2016) Physical land suitability is a prerequisite for the development of land use planning, as it indicates decisions on land use catagory to take the most advantage, and supports to land management better, reduce soil degradation and design effective land use models (Van Ranst et al., 1996; Nahusenay and Kibebew, 2015) On other words, a part of land-use measures is land evaluation to support land use planning and rational use of natural and human resources (Rossiter, 1996) Different techniques and softwares have been built in order to further improve the accuracy of land evaluation These include Land Evaluation Computer System (LECS), Automated Land Evaluation System (ALES), Intelligent System for Land Evaluation (ISLE), and integrated expert system with multimedia (LIMEX), etc The evaluation used to be quite simple, the criteria in land evaluation were equally important Currently, the need for sustainable development makes analysis for appropriate land use increasingly complex due to the consideration of more requirements/criteria The weight value is applied to indicate the importance of each criteria for a specific object or study area Land evaluation conducted by Geographic Information Systems (GIS) and multi-criteria analysis has been widely used in recent years (Malczewski, 2006, Baja et al., 2007; Jafari and Zaredar, 2010; Mendas and Delali, 2012; Nguyen et al., 2015; Ennaji et al., 2018) Analytical Hierarchy Process (AHP) is a tool to assess the relative importance of each criteria, the weights in AHP can be estimated by or geometric averages or Fuzzy logic (Prakarsh, 2003; Kurterer et al., 2008; Akıncı et al., 2013; Kamkar et al., 2014; Zang et al., 2015; Widiatmaka, 2016; Maddahi et al., 2017; Jamil et al., 2018) Each approach of land evaluation has different inputs and quality (Nahusenay and Kibebew, 2015) There are no rules indicating that a certain approach is adequate, or it need a more complex level of analysis In the context of Vietnam as a newly poverty-escaped country, the database of land resources is limited and asynchronous, especially large-scale data; limited funding makes detailed data analysis far to reach FAO’s land evaluation method applies automatic evaluation software such as ALES in combination with GIS to analyze the space and map display The results are widely used such as D’haeze et al.,2005; Dinh, 2007, Ngoc et al, 2013, etc Macro-level land evaluations have contributed in the first step of completing the FAO’s land evaluation process in Vietnam and provided useful results as a basis for national land planning strategies and large ecological areas planning To date, land research and evaluation at the micro level, with the detailed evaluation object and study area is an urgent requirement It is in order to specify national land planning strategies and develop land use orientations for each locality Therefore, more complex quantitative land evaluation methods have been implemented (Giap et al., 2005; Son and Shrestha, 2008; Khoi and Murayama, 2010; Nguyen et al., 2015) This paper was conducted to evaluate the suitable land areas for orange and tea trees in the Western Nghe An by two evaluation methods Firstly, a traditional and popular method in Vietnam: ALES (Automated Land Evaluation System) software Secondly, a new method which established on the GIS-MCA platform: LSE software (Land Suitability Evaluation) The study selected the same input data of soil, climate and topography for the two methods, thereby comparing two results and comparing with actual farming situation to verify Then, assessing the overall land suitability, taking into account the socio-economic and environmental criteria to determine the most suitable areas for orange and tea development for the the Western Nghe An Methodology 2.1 Case study Nghe An is a province in the central position of the North Central region of Vietnam It belongs to the Northeast of Truong Son Mountain Range, the topography is diverse, complex and divided by mountainous systems with three distinct ecological regions: mountainous, midland, coastal plain This study focused on the Western Nghe An area including 11 mountainous districts and towns of Nghe An province namely Thanh Chuong, Anh Son, Con Cuong, Tuong Duong, Ky Son, Que Phong, Quy Chau, Quy Hop and Tan Ky, Nghia Dan and Thai Hoa Town ( Figure Study area in Vietnam territory ) The region has an area of 1,375,104 ha, about 84% of Nghe An province The Western Nghe An is characterized by two soil groups such as: Acrisols and Ferralsols, about 1,070,650 ha, accounting for 74.3% of the area Especially Rhodic Ferralsols built on basalt with soil structure and nutritions are very favorable for perennial crops and fruit trees The Western Nghe An has a monsoon tropical climate with a cold winter The topography of the Truong Son mountain range substantially influences the monsoon circulation and creates the regional climatic differentiation There are two distinct seasons: hot, humid, heavy rain in summer and less rain in winter The mean annual temperature is about 23-24ºC at an altitude of less than 200m, corresponding to the total heat of 8,700ºC The maximum temperatures can reach extreme values up to 42-43ºC in April and May The temperature decreases with height, reaches 20ºC at an altitude of 700m, and about 15-18ºC at an altitude of 1,100-1,700m The precipitation varies in a quite wide range from 1,000 mm to over 2,100 mm with 120-150 rainy days Rain regime in the area is divided into two distinct seasons: rainy season and less rainy season The rainy season coincides with the summer monsoon season, lasting months, from May to October (Ngoc et al., 2019) Figure Study area in Vietnam territory 2.2 Methods 2.2.1 Land suitability evalution in ALES ALES (Automated Land Evaluation System) was developed in 1986-1996 by Rossiter and Wambeke (1997) ALES is an abundant expert system environment in land evaluation toolkit in the world FAO’s land suitability evaluation has started in Vietnam in the late 80s Based on the FAO land evaluation framework (1976), ALES is a land suitability evaluation software which firsly used in 2000 to support land use planning, especially for agricultural and forestry land To date, there are more evaluation methods but ALES is still very common Because ALES has a number of advantages that are relevant to the actual conditions in Vietnam such as: The order of land evaluation according to FAO guidelines is applied with the integration of geographic information system GIS, ALES software and computer support ALES 4.65 software can be installed and run smoothly on Window 7-32bit With this program, users completely take the initiative in inputting data into the computer as required by the program and it provides prompt results including the following parameters: Natural adaptation, yield estimation, analysis economic parameters Input data for simple natural adaptation evaluation: are Land Use Requirements (LUR), the base unit for evaluation is Land Unit Map (LUM), including a set of Land units (LU) with attribute data After creating a Decision tree, importing LUM attribute data into ALES can promply provide appropriate results This is particularly advantageous when simultaneously evaluating multiple Land Utilization Types (LUT) or initiative attribute data including multiple complex LURs or large number of LUs Land suitability evaluation results not only indicate the suitability of S1, S2, S3, N but also justify for ranking at that level in the form of Physical suitablitity subclass Steps on ALES are simple No complex interpolation or analysis is required However, ALES itself does not have the functions in map display and spatial analysis Users are required to export ALES evaluation results to GIS to perform spatial analysis The classification of ALES seems too strict Only one attribute element of the LU does not meet the LUR in that class, then LU is immediately ranked lower This may be true in the case that LURs is limited However, for normal or remedial LURs, this decentralization is too thorough This problem can be solved if ALES has a weighting tool, assigning weight to LURs to provide final result The appropriate land evaluation steps in ALES is shown in Error! Reference source not found and summarized as follows: Develop the LUM by overlaying the selected input data Select LUR of each LUT On ALES, set LUR of LUT with attributes corresponding to the attributes of LU Develop a Decision tree and selecting maximum limitation for the suitability classification Import LU definition from xBase to ALES Perform suitability calculations, ALES allows the selection of LU to evaluate, the evaluation results are displayed in the form of Physical suitabilitiy subclass Export and save evaluation results from ALES into data field in LUM database, then set up suitability evalutaion map and calculations in GIS 2.2.2 Land suitability evalution in LSE LSE is the first software in Vietnam to be developed for land suitability evaluation It is integrated in Visual Basic, it is stand-alone software that follows the land evaluation process based on multi-criteria analysis in GIS environment of Nguyen et al., 2015 LSE is based on open source GIS - DotSpatial It performs all operations in Geotif format Eventually, two converters were built with conversion vectors (.SHP input format) and raster data (Grid, IMG and BGD file formats) in Geotif LSE includes the main parts: (1) Interface with input fields and operation keys; (2) Spatial database including maps; (3) Model of land evaluation to carry out calculation and production of results maps; (4) Supporting tools: Data conversion, Slope data building, Grouping, Standardizing, Verifying results, Viewing maps) The steps for conducting an land suitability evaluation in LSE is shown in Error! Reference source not found and is described as follows: Develop criteria data according to ecological adaptation table and select standardized functions Use algorithm functions in software to standardize data The standardized data was developed by: the S membership, a trapezoidal, the Kandel function Determine and calculate weights The weights are determined by the rank reciprocal equation Evaluate component adaptation according to each criteria group Overall suitability evaluation according to all criteria groups LSE is a compact, scientific-based and flexible software with friendly interface It is very useful in evaluating regional land suitability, it saves time and ensures accuracy and objectivity LSE is a new software, the influence calculation tool has not been fully integrated into the software While running, users need to use an additional supporting software to calculate The selection of the standardized function is difficult for users Automatic selection feature has not developed yet Figure Process of the study 2.2.3 Method of evaluating soil erosion and mapping orange and tea areas Annual soil erosion for orange and tea cultivation is estimated according to the formula Universal Soil Loss Equation (USLE) developed by Wischmeier et al (1978) and shown Figure A= R x K x L x S x C x P (1) Where, R factor is calculated by the fomula: R= 0.082 x P - 21 of Lai (1999), P is annual rainfall Soil erodibility factor K is estimated based on the interaction with soil organic matter (OM) of Stone et al (2012) ( Table 10) LS factor is is calculated by the fomula: LS = (L/22,1)0,7(6,432sin(S0,79)cos(S) Where, L is length of slope (m); S is slope angle (radian) Map of LS coefficient is referenced by Dung et al (2013) Study to apply cover management factor C=0.2 for tea trees according to Kuok et al (2013), C=0.13 for orange trees according to Shi et al (2004) The support practice factor P applied to tea trees is 0.6 Kuok et al (2013) and 0.5 for orange trees according to Prasannakumar et al (2012) (a) (b) Figure Annual soil erosion corresponds to growing orange (a) and tea (b) Table 10: Estimates of K factor based on soil texture and organic matter (OM) content Textural Class K Factor Average OM2% Clay 0.22 0.24 0.21 Clay loam 0.30 0.33 0.28 Loamy sand 0.04 0.05 0.04 Sandy clay loam 0.20 0.20 0.20 Sandy loam 0.13 0.14 0.12 The study has established a map of orange and tea cultivation in Yen Khe commune (Con Cuong) and Minh Hop commune (Quy Hop) to support the verification of land evaluation results This map is built on the basis of Land use map of Yen Khe commune, Minh Hop commune 2016 with a ratio of 1:10,000 (DNRENA, 2017) and SPOT5 image at the time of 2017 2.3 Data The criteria selected to land evaluation of the Western Nghe An for oranges and tea, were divided into three parameters There are parameters of climate (annual precipitation, mean annual temperature, length of dry season, mean temperature of months after harvest, mean temperature of flowering period of orange trees); parameters of topography (slope, flooding, drainage); parameters of soil (soil depth, soil texture, pH, OM, CEC, available phosphorus, available potassium) Soil physical data including soil depth and soil texture were taken from soil map of Nghe An province at scale 1:100,000 (NIAPP, 2004) (Figure 10) Soil nutrient criteria: pHH2O, OM, P2O5, K2O, CEC are calculated from the results of chemical analysis of 79 soil profiles in the study area and surrounding areas (a) (b) (d) (c) (e) Figure 10 Spatial distribution of: (a) Slope, (b) Soil depth, (c) Soil texture, (d) Drainage, (e) Flooding Value of pHH2O, OM and available potassium, available phosphorus is the result of calculating the average of soil layer 0-25 cm (Sys et al., 1991) These nutritional criteria of the study area are shown in Figure (a) (b) (c) (d) (e) Figure 11 Nutritional criteria of the study area: (a) Soil pH, (b) Soil Organic Matter, (c) Soil CEC, (d) Available potassium, (e) Available phosphorus Climate data include annual precipitation, mean annual temperature, length of dry season, mean temperature of months after harvest, mean temperature of flowering stage (Figure 12) These maps were established on a series of monitoring data including: precipitation data of 22 regional hydrological stations; especially temperature and precipitation data at 04 meteorological stations in Con Cuong, Tuong Duong, Quy Hop and Quy Chau for a period of 35 years from 1980 to 2014 (DCG, 2016) The mean temperature of flowering of orange trees in the Western Nghe An is calculated as the mean temperature in January and February The mean temperature of months after harvest of orange trees is calculated as the mean temperature of months (December, January, February) Topography data: Slope angle were extracted from the 30m resolution DEM (Figure 10) Flood data is referenced from flooding map of the North Central region at scale 1:250,000 from Thuy, (2015) and presented in Figure 10e On the basis of soil map, drainage is determined based on the occurrence of the glei layer in soil profile, shown in Figure 10d (Sys et al., 1991) In addition, to make an overall suitability evaluation in the LSE, there is also data on the distance to the market, the distance to the road Market data and traffic axes are taken from the topographic map of 1: 50,000 scale and supplemented from the land use map at 1: 10,000 scale in 2016 Then, the distance to the market and distance to the road are calculated by Euclidean Distance in Arcgis 10.1 Nghia Đan - 30,101 19,649 10,732 1,294 61,776 Tan Ky - 31,638 14,890 17,542 8,847 72,918 Quy Chau - 38,880 47,038 18,156 1,692 105,766 Quy Hop - 35,703 34,629 10,809 13,125 94,266 Que Phong - 29,446 88,941 67,262 3,437 189,087 Con Cuong - 22,909 91,704 51,234 8,035 173,881 Tuong Duong - 6,101 122,62 148,48 3,920 281,130 101,59 101,46 1,423 209,434 Ky Son - 4,954 Thai Hoa - 2,153 9,042 1,911 379 13,484 Total (ha) - 228,43 568,53 527,79 50,332 1,375,10 16.6 41.3 38.4 Ratio (%) - (a) 3.7 100.0 (b) Figure 13 Maps of ecological suitability for orange cultivation: (a) Results by ALES; (b) Results by LSE Suitability evaluation results for tea in the Western Nghe An may find that in fact the tea growing area is considerably large, however, the results by ALES provide that the Very suitable (S1) and the Moderately suitable (S2) areas are very small (Table 14, Error! Reference source not found.) Occupying about 0.3% and 7.2% respectively, mainly in Thanh Chuong, Anh Son and Con Cuong districts The unsuitable areas for tea cultivation is mainly in the western part of the region (in Ca river valley) due to the limitations of climate (low rainfall, long dry season), slope angle, soil depth, pH The annual precipitation 30o, poor drainage, soil texture including clay and sand, soil depth 100 cm, well drainage, soil texture from clay to loamy sand The optimal distance to the road is less than km, and to the market is less than km Annual soil erosion does not exceed the soil loss limit The eastern part of the study area is moderately suitable, which accounts for 20.68% (Table 24) Meanwhile, the western mountains are unsuitable marginally suitable to orange cultivation The very suitable for tea cultivation is relatively similar to the very suitable for orange cultivation It covers 69,388.8 ha, accounting for about 5.05% of the total area The spatial distribution of suitability class is shown in Figure 12 and total area is shown in Table 24 The soil erosion have a significant influence on the results of the overall evaluation, which makes the area unsuitable for highland tea cultivation, approximately 61.54% (846,180.6 ha) Table 24 The overall suitabily evaluation for orange and tea cultivation in the Western Nghe An Crop LSE suitability class Orange Tea Total area (ha) S1 S2 S3 N Area (ha) 64,505.9 284,386.8 310,244.3 715,967.0 1,375,104.0 % of total area 4.69 20.68 22.56 52.07 100.0 Area (ha) 69,388.8 247,150.1 212,384.5 846,180.6 1,375,104.0 % of total area 5.05 17.97 15.44 61.54 100.0 (a) (b) Figure 18 Overall land suitability for orange cultivation (a) and tea cultivation (b) Thus, comparing with the orientation of orange development planning and commercial tea production up to 2030 of Nghe An province, the very suitable (S1) is fully satisfied Specifically, the orange cultivation area will be stable to 7,000 by 2030, the concentrated tea cultivation area will cover 12,000 (PCNAP, 2016a, 2016b) However, the priority to expand to the surrounding area, where people have rich tradition and experience, is necessary Then, a concentrated production area will be established for intensive farming and application of science and technology It is recommend to establish orange production areas in Quy Hop and Con Cuong, and tea production areas in Thanh Chuong, Anh Son and Con Cuong The overall suitability evaluation reveals that it is necessary to review the current situation of cultivation, to retain high-quality farms, to convert the less productive farms, to replace the orange and tea farms where are out of production cycle, then establish new planting areas Conclusions and discussion In conclusion, if the GIS-integrated ALES software demonstrates acuracy of the limiting criteria in land evaluation, the land evaluation process of the LSE on the GIS-MCA platform has proven to be advantageous in identification of larger suitable areas than ALES This partly reflects the current sitation of orange and tea cultivation in the Western Nghe An, when limited criteria will be addressed and improved by advanced science and technology This study shows that LSE software has a number of advantages, especially weighting criteria to emphasize the impact of dominant criteria or reduce the impact of normal ones in overall land evaliation, LSE also has certain limitations The weight estimator and accuracy assessment have not been fully integrated, and selection of standardized function needs to be improved Results of ecological suitability evalution of orange cultivation by LSE shows that the area of very suitable (S1) and moderately suitable (S2) are 188,668 (13.7%) and 421,353 (30.6%) respectively The calculation results by LSE also shows that the Western Nghe An is suitable for tea cultivation, very suitable (S1) accounting for 19.2% (264,210 ha), the moderately suitable (S2) has 40.2% Meanwhile, according to ALES, there is no area suitable for orange, the highest level is S2 with 228,439 (16.6%) Suitable land for tea with limited area is S1: 4,131ha (0.3%) and S2: 98,812 (7.2%) In addition to the specifically selected agro-ecological criterai, the study also evaluates the environmental and socio-economic sustainability of the proposed land use This is reflected in the overall evaluation The evaluation results have found that the Western Nghe An has 64,505.9 (4.69%), which is very suitable for orange cultivation, 69,388.8 (5.05%), very suitable for tea cultivation, fully meeting the regional cultivation planning up to 2030 Therefore, the evaluation results can be used to prioritize the development of specialty crops such as orange and tea in the study area or to establish an appropriate land use planning schemes Acknowledgements This article was supported by VAST Project, code: VAST05.01/16-17 References Akıncı, H., Özalp, A Y., & Turgut, B (2013) Agricultural land use suitability analysis using GIS and AHP technique Computers and electronics in agriculture, 97: 71-82 Baja, S., Chapman, D M.,Dragovich, D (2007) Spatial based compromise programming for multiple criteria decision making in land use planning Environmental Modeling and Assessment, 12(3) Department of Climatological Geography (DCG), 2016 The precipitation and temperature data at meteorological measuring stations in the West of Nghe An Province between 1984 and 2014 Data stored at Department of Climatological Geography, Institute of Geography, Ha Noi, 46p Department of Natural Resources and Environment in Nghe An (DNRENA) (2017) Land use map in Yen Khe commune, Minh Hop commune in 2016 D’haeze, D., Deckers, J., Raes, D., Phong, T A., Loi, H V., (2005) Environmental and socio-economic impacts of institutional reforms on the agricultural sector of Vietnam: Land suitability assessment for Robusta coffee in the Dak Gan region Agriculture, ecosystems & environment, 105(1-2): 59-76 Dinh, L C (2007) Integrated ALES and GIS for land evaluation in Cam My district, Dong Nai province Journal of Agricultural and Forestry Sciences, 1&2: 206-213 Dung, N V., Ky, N D (2012) Quantitive assessment soil erosion by USLE and GIS in mountains and hills, Thanh-Nghe-Tinh region Vietnam journal of Earth sciences, 34 (1): 3137 Ennaji, W., Barakat, A., El Baghdadi, M., Oumenskou, H., Aadraoui, M., Karroum, L A., & Hilali, A (2018) GIS-based multi-criteria land suitability analysis for sustainable agriculture in the northeast area of Tadla plain (Morocco) Journal of Earth System Science, 127(6) FAO, 1993 Guidenlines for land-use planning FAO Development series 1, 135 Fruit and vegetable research institute (FAVRI), 2011 Quy trình quản lý trồng tổng hợp cam xã Đoài http://www.favri.org.vn/index.php/vi/20-sa-n-pha-m-khoaha-c-ca-ng-ngha/ca-y-n-qua/quy-tra-nh-va-tia-n-ba-ka-thua-t/100-quy-trinh-qu-n-ly-cay-trng-t-ng-h-p-tren-cay-cam-xa-doai (accessed on 11/10/2017) Giap, D H., Yi, Y., Yakupitiyage, A (2005) GIS for land evaluation for shrimp farming in Haiphong of Vietnam Ocean & Coastal Management, 48(1): 51-63 Hong, N.V (2017) Analysis and evaluation of landscapes to support agricultural and forestry development and biodiversity conservation in southwestern districts of Nghe An province PhD in Geography, VNU, 183p Jafari, S., Zaredar, N (2010) Land suitability analysis using multi attribute decision making approach Int J of Environ Sci and Develop 1: 2010-2064 Jamil, M., Ahmed, R., & Sajjad, H (2018) Land suitability assessment for sugarcane cultivation in Bijnor district, India using geographic information system and fuzzy analytical hierarchy process GeoJournal, 83(3): 595-611 Kamkar, B., Dorri, M A and Silva, J A T D (2014) Assessment of land suitability and the possibility and performance of a canola (Brassica napus L.) - soybean (Glycine max L.) rotation in four basins of Golestan province, Iran The Egyptian J of Remo Sens and Space Sci 17: 95 -104 Khang, D (1999) Assessment of Nghe An hills and mountains and proposal models of land use for forestry and agriculture (10 mountainous districts) PhD in Geography, Hanoi University of Education, 155p Khoi, D D and Murayama, Y (2010) Delineation of suitable cropland areas using a GIS based multi-criteria evaluation approach in the Tam Dao National Park Region, Vietnam Sustainability 2: 2024-2043 Kuok, K.K., Mah, D.Y., Chiu, P.C (2013) Evaluation of C and P factors in Universal Soil loss equation on trapping sediment: Case study of Santubong river Journal of water resource and protection 2013 (5): 1149-1154 Kurtener, D., Tobert, H A and Krueger, E (2008) Evaluation of agricultural land suitability: application of fuzzy criteria, ICCSA Springer-Verlag Berlin Heidelberg 5072: 475490 Lai, V.C (1999) Soil erosion in north-western region of Vietnam Ph.D thesis Warsaw University, Warsaw Maddahi, Z., Jalalian, A., Zarkesh, M K., Honarjo, N (2017) Land suitability analysis for rice cultivation using a GIS-based fuzzy multi-criteria decision making approach: central part of Amol district, Iran Soil and Water Research, 12(1): 29-38 Makczewski, J., (2004) GIS-based land-use suitability analysis: A critical overview Progress in Planning 62: 3-65 Mendas, A., Delali, A (2012) Integration of MultiCriteria Decision Analysis in GIS to develop land suitability for agriculture: Application to durum wheat cultivation in the region of Mleta in Algeria Computers and Electronics in Agriculture, 83: 117-126 Ministry of Science and Technology of Vietnam (MOST), (2010) TCVN 8409: 2010 Land evaluation process for agricultural production in service of district land use planning, Hanoi Nahusenay, A., Kibebew, K., 2015 Land suitability evaluation in Wadla Delanta Massif of north central highlands of Ethiopia for rainfed crop production African Journal of Agricultural Research, 10(13) National Institute of Agricultural Planning and Projection (NIAPP), 2004 Report of the soil map of Nghe An (attached map at scale 1: 100,000), 80p Nghe An statistics office (NASO), 2018 Nghe An statistical yearbook 2017 Nghe An Publishing House, Vietnam, 571p Ngoc, H T H, Ky, N D., Anh, L T (2013) Application of an integrated ALES-GIS model in land suitability evaluation for tea cultivation in Bao Loc - Di Linh area Vietnam Journal of Earth Sciences 35(3): Ngoc, H.T.H, Van, T.T.T., Ha, N.M., Binh, N.Q., Tan, M.T (2019) Bioclimatic assessments for tea cultivation in Western Nghe An Vietnam Journal of Earth Sciences, 41(1): 81-94 Nguyen, T T., Ann, V., Tran, V Y., Nele, D., Tran, T C., Eric, V R (2015) Design of a GIS and multi-criteria based land evaluation procedure for sustainable land use planning at regional level Journal of Agriculture, Ecosystems and Environment, (200) Olusegum A J, Julius A (2015) Land evaluation and management of an utilisol for fruit crops production in South Southern Nigeria Journal of Global Biosciences, 4(4): 1982-1989 Pimhidzai, O (2018) Climbing the ladder: poverty reduction and shared prosperity in Vietnam Vietnam poverty and shared prosperity update report Washington, DC: World Bank Group Prakash, N T., (2003) Land suitability analysis for agricultural crops: A fuzzy multicriteria decision making approach International Institute for Geo Information Science and Earth Observation Enschede, The Netherlands, 1-57 Prasannakumar, V., Vijith, H., Abinod, S., Geetha, N (2012) Estimation of soil erosion risk within a small mountainous sub-watershed in Kerala, India, using RUSLE and geoinformation technology Geoscience Frontiers 3(2): 209-215 Quy, C H (1995) Overview of highland development in Vietnam: General characteristics, socio-economic situation, and development challenges The Challenges of Highland Development in Vietnam, 244 pg Quy, D.N., (2003) Tea in Vietnam, Production - Processing - consumption Nghe An Publisher 2003 Roozitalab, M H., Serghini, H., Keshavarz, A., Eser, V.,de-Pauw, E (2013) Sustainable agricultural development of highlands in central, West Asia and North Africa International Center for Agricultural Research in the Dry Areas (ICADAR), 52 Rossiter, D G., (1996) A theoretical framework for land evaluation Geoderma, 72 (1996), 37 Rossiter, D.G., Wambeke, A.V., (1997) Automate land evaluation system ALES version 4.65 user's manual Cornell university Shi, Z H., Cai, C F., Ding, S W., Wang, T.W., Chow, T L., (2004) Soil conservation planning at the small watershed level using RUSLE with GIS: a case study in the Three Gorge area of China Cantena, 55 (2004): 33-48 Singha, C.,Swain, K C., 2016 Land suitability evaluation criteria for agricultural crop selection: A review Agricultural Reviews, 37(2) Son, N T., Shrestha, R P., (2008) GIS-assisted land evaluation for agricultural development in Mekong delta, southern Vietnam Journal of Sustainable Development in Africa, 10(2): 875-895 Stone, R.P., Hilborn, D., (2012) Universal Soil Loss Equation (USLE) factsheet Ministry of Agriculture, Food and Rural Affairs, Ontariontim Sys, C., Van Ranst, E., Debaveye, J., (1991) Land evaluatio - Part I - Principles in land evaluation and crop production calculations Agricultural Publications - No General Administration for Development Cooperation, Brussels, Belgium Sys, C., Van Ranst, E., Debaveye, J., Beernaert, F., (1993) Land evaluation - Part III Crop requirements Agricultural Publications - No General Administration for Development Cooperation, Brussels, Belgium The People’s Committee of Nghe An Province (PCNAP), (2016a) Decision No 3773/QD-UBND dated August 5, 2016 on approving the planning of citrus development in Nghe An province to 2020, vision to 2030 The People’s Committee of Nghe An Province (PCNAP), (2016b) Decision No 3396/QĐ-UBND dated August 6, 2016 on approving the agricultural production development planning of Nghe An province in 2020, with a vision to 2030 Thuy, T H L, (2015) Assessment of the vulnerability of the socio-economic system in context of climate change in the North Central region Program KHCN-BDKH 11/15 Main report of the national project, typing version, Institute of Geography, Hanoi Van Ranst, E., Tang, H., Groenemam, R.,Sinthurahat, S., (1996) Application of fuzzy logic to land suitability for rubber production in peninsular Thailand Geoderma, 70(1) Vietnamese Government (VG), (2015) Decision No 59/2015/QD-TTg of PM dated November 19, 2015 v promulgating multidimensional poverty levels applicable during 2016-2020 Vietnam Vietnamese Government (VG), (2016) Decision No 2085/QD-TTg of PM dated October 31, 2016 accrediting specific policy support socio-economic development in mountainous and ethnic minority area from 2017 to 2020 Vietnamese Government (VG), (2017) Decision No 900/QD-TTg of PM dated June 20, 2017 approving the list of communes in special difficulty, communes near border and in the safe zone which are invested by Program 135 term 2017 - 2020 Vietnamese Government (VG), (2018) Evaluate the results of years of implementing policies to support socio-economic development in ethnic minority and mountainous areas (2016-2018) Committee for Ethinic Minority Affairs Widiatmaka, W., (2016) Integrated use of GIS, AHP and remote sensing in land use planning for tropical high altitude vegetable crops Journal of Applied Horticulture , 18(2): 8799 Wischmeier, W H., Smith, D D., (1978) Predicting rainfall erosion losses: A guide to conservation planning Agricultural Handbook, vol 537, Washington, D.C, 85 pp Zhang, J., Su, Y., Wu, J., Liang, H., (2015) GIS based land suitability assessment for tobacco production using AHP and fuzzy set in Shandong province of China Computers and Electronics in Agriculture, 114: 202-211 Vogel, R., (2008) A software framework for GIS-based multiple criteria evaluation of land suitability 11th AGILE International Conference on Geographic Information Science, University of Girona, Spain, p.1 Belal, A A., Mohamed, E S., Abu-hashim, M S D., (2015) Land evaluation based on GIS- Spatial multi-criteria evaluation (SMCE) for Agricultural development in Dry Wadi, Eastern Desert, Egypt International Journal of Soil Science, 10: 100-116 Das, P T., Sudhakar, S., (2014) Land suitability analysis for orange & pineapple: A multi criteria decision making approach using geo spatial technology J Geogr Info Sys 6: 40-44 Joshua, J., Kunda, J., Anyawu, A., Neoma, C., Ahmed, A and Jajere, A., (2013) Land suitability analysis for agricultural planning using GIS and multi criteria decision analysis approach in Greater Karu Urban Area, Nasarawa StateNigeria Int J of Applied Research and Studies 2: 1-10 ... the accuracy of land evaluation These include Land Evaluation Computer System (LECS), Automated Land Evaluation System (ALES), Intelligent System for Land Evaluation (ISLE), and integrated expert... 2007; Singha and Swain, 2016) Physical land suitability is a prerequisite for the development of land use planning, as it indicates decisions on land use catagory to take the most advantage, and. .. environment in land evaluation toolkit in the world FAO’s land suitability evaluation has started in Vietnam in the late 80s Based on the FAO land evaluation framework (1976), ALES is a land suitability