基于最大熵模型（MaxEnt）和地理信息系统（GIS）的四川省眉山市东坡区晚熟柑橘适宜性评价

doi:10.3864/j.issn.0578-1752.2025.04.010

Abstract

Abstract:

【Objective】Carrying out the suitability evaluation of late-maturing citrus in Dongpo District, Meishan City, can provide scientific references for the reasonable cultivation and optimization of production space of local late-maturing citrus. 【Method】Based on 14 climatic indicators, 3 topographic indicators and 22 soil physicochemical indicators, as well as data from 372 sampling points of late-maturing citrus planting areas, the article utilizes the Maximum Entropy Model (MaxEnt) and Geographic Information System (GIS) in combination with correlation analysis to screen key environmental factors affecting the distribution of late-maturing citrus in Dongpo District, Meishan City, Sichuan Province, and constructs a model for evaluating the suitability of late-maturing citrus planting. The model was constructed to evaluate the suitability of late-maturing citrus planting.【Result】The MaxEnt model was very effective, and the area under the curve (AUC) in the characteristic working curve (ROC curve) of the subjects reached 0.843, which was highly accurate and reliable. The MaxEnt analysis showed that the average annual air temperature, elevation, total phosphorus, pH, average annual relative humidity, pulverization, annual precipitation, annual sunshine hours, autumn precipitation, soil exchangeable calcium, total potassium and organic matter were the main environmental factors affecting the distribution of late-maturing citrus; the cumulative contribution of climatic variables affecting the distribution of citrus was 43.0%, of which mean annual temperature (22.9%), mean annual relative humidity (7.0%) and annual precipitation (4.6%) were the three most important climatic factors affecting the distribution of late-maturing citrus; the cumulative contribution of soil variables affecting the distribution of late-maturing citrus was 41.3%, of which total phosphorus (13.8%), pH (10.4%) and chalkiness (5.7%) were the three most important soil factors affecting the distribution of late-maturing citrus; elevation was a topographic factor affecting the distribution of citrus, with a contribution rate of 15.7%. By statistically analyzing the parameter values of each dominant environmental factor in different levels of distribution areas, combining the response curves of each ecological factor, the field survey and the review of the literature, a comprehensive analysis was made to conclude that the basic climatic and topographical environmental requirements for the distribution of late-maturing citrus are as follows: the average annual air temperature is about 17 ℃, the average annual relative humidity is 80%, the annual rainfall is about 1 300 mm, the annual sunshine hours are 1 350 h, and the rainfall in autumn is about 390 mm, altitude of about 400-700 m; soil pH of 4.5-7.5, while the soil nutrient status is affected by the combination of standing conditions and cultivation and management measures. Of the 34 673.29 hm² of gardenable land in the region, 23.51%, 61.37% and 15.12% were in the dominant, suitable and unsuitable zones, respectively.【Conclusion】This study objectively reflects the changing characteristics of late-maturing citrus planting suitability, suitable area and distribution in Dongpo District under the influence of climate, topography and soil factors.

Key words: late maturing citrus, maximum entropy model, geographic information system, suitability evaluation

YAO Li, DENG ChunXiu, TANG Biao, WANG Hong, WU YueYing, ZHANG Qi, LI YuanHong, LIU ZhongYou, LU ChangAi, LIN ChaoWen. Suitability Evaluation of Late Maturing Citrus in Dongpo District, Meishan City, Sichuan Province Based on Maximum Entropy Model (MaxEnt) and Geographic Information System (GIS)[J].Scientia Agricultura Sinica, 2025, 58(4): 748-758.

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References 31

[1]	汪君, 杜兴端. 四川柑橘产业发展形势与建议. 四川农业科技, 2022(7): 62-65, 69.
	WANG J, DU X D. Development situation and suggestions of Citrus industry in Sichuan province. Sichuan Agricultural Science and Technology, 2022(7):62-65, 69. (in Chinese)
[2]	耿学燕, 杨锦秀. 四川省柑橘产业发展竞争力简析. 农村经济, 2013(1): 60-64.
	GENG X Y, YANG J X. Analysis on the development competitiveness of Citrus industry in Sichuan province. Rural Economy, 2013(1): 60-64. (in Chinese)
[3]	祁春节, 顾雨檬, 曾彦. 我国柑橘产业经济研究进展. 华中农业大学学报, 2021, 40(1): 58-69.
	QI C J, GU Y M, ZENG Y. Progress of citrus industry economy in China. Journal of Huazhong Agricultural University, 2021, 40(1): 58-69. (in Chinese)
[4]	邓超, 李坤冀, 项朋志. 基于最大熵模型(MaxEnt)和地理信息系统(GIS)的麻竹中国适生分布格局研究. 环境生态学, 2023(10): 69-74.
	DENG C, LI K J, XIANG P Z. Study on the distribution pattern of Dendrocalamus latiflorus in China based on the maximum entropy model (MaxEnt) and geographic information system (GIS). Environmental Ecology, 2023(10): 69-74. (in Chinese)
[5]	赵金鹏, 王明田, 罗伟, 李强, 王庆, 王茹琳. 佛手在川渝地区的生态适宜性及潜在分布. 应用与环境生物学报, 2023, 29(6): 1356-1363.
	ZHAO J P, WANG M T, LUO W, LI Q, WANG Q, WANG R L. Ecological suitability and potential distribution of Citrus medica in the Sichuan-Chongqing region. Chinese Journal of Applied and Environmental Biology, 2023, 29(6): 1356-1363. (in Chinese)
[6]	秦明星, 焦丽娜, 杨忠义, 王佳星, 纪薇. 基于MaxEnt和GIS的山西省连翘潜在分布及适宜性分析. 中国农业资源与区划, 2021, 42(6): 109-117.
	QIN M X, JIAO L N, YANG Z Y, WANG J X, JI W. Potential distribution prediction and suitability evaluation of forsythia based on MaxEnt and GIS in Shanxi province. Chinese Journal of Agricultural Resources and Regional Planning, 2021, 42(6): 109-117. (in Chinese)
[7]	吕彤, 郭倩, 丁永霞, 刘力, 彭守璋. 基于MaxEnt模型预测未来气候变化情景下中国区域水稻潜在适生区的变化. 中国农业气象, 2022, 43(4): 262-275.
	LÜ T, GUO Q, DING Y X, LIU L, PENG S Z. Predicting potential suitable planting area of rice in China under future climate change scenarios using the MaxEnt model. Chinese Journal of Agrometeorology, 2022, 43(4): 262-275. (in Chinese)
[8]	陈程浩, 龙主多杰, 陆徐伟, 宋扎磋, 苗琪, 孙芳慧, 索南吉. 基于优化MaxEnt模型的中国紫堇属植物生境适宜性研究. 生态学报, 2023, 43(24):10345-10362.
	CHEN C H, LONG Z D J, LU X W, SONG Z C, MIAO Q, SUN F H, SUO N J. Habitat suitability of Corydalis based on the optimized MaxEnt model in China. Acta Ecologica Sinica, 2023, 43(24): 10345-10362. (in Chinese)
[9]	习文勇, 傅佩红. 基于模糊数学的柑橘种植土地适宜性评价. 浙江农业学报, 2022, 34(1): 141-152. doi: 10.3969/j.issn.1004-1524.2022.01.17
	XI W Y, FU P H. Land suitability evaluation of citrus cultivation based on fuzzy mathematics. Acta Agriculturae Zhejiangensis, 2022, 34(1): 141-152. (in Chinese) doi: 10.3969/j.issn.1004-1524.2022.01.17
[10]	邓丹丹, 周鹏, 邓龙辉, 李成龙. 奉节县柑橘适宜性评价. 安徽农业科学, 2018, 46(19): 4-8.
	DENG D D, ZHOU P, DENG L H, LI C L. Suitability evaluation for Citrus in Fengjie County. Journal of Anhui Agricultural Sciences, 2018, 46(19): 4-8. (in Chinese)
[11]	林正雨, 陈强, 邓良基, 李晓, 何鹏, 唐莎. 基于MaxEnt和MCR的四川省柑橘生产布局模拟. 中国农业资源与区划, 2019, 40(9): 64-74.
	LIN Z Y, CHEN Q, DENG L J, LI X, HE P, TANG S. Simulation of citrus production layout in Sichuan province based on MaxEnt and MCR. Chinese Journal of Agricultural Resources and Regional Planning, 2019, 40(9): 64-74. (in Chinese)
[12]	苏婷婷, 周鑫斌, 徐墨赤, 吴桃红, 高阿祥, 石孝均. 重庆市柑橘园土壤养分现状研究. 土壤, 2017, 49(5): 897-902.
	SU T T, ZHOU X B, XU M C, WU T H, GAO A X, SHI X J. Study on nutrient status of Citrus orchard soil in Chongqing. Soils, 2017, 49(5): 897-902. (in Chinese)
[13]	李潇, 吴克宁, 刘亚男, 高先虎. 基于土地类型的西峡县农用地适宜性评价. 中国农业资源与区划, 2024, 45(1): 45-56.
	LI X, WU K N, LIU Y N, GAO X H. Suitability evaluation of agricultural land based on land type in the Xixia County. Chinese Journal of Agricultural Resources and Regional Planning, 2024, 45(1): 45-56. (in Chinese)
[14]	AGUIRRE-GUTIÉRREZ J, CARVALHEIRO L G, POLCE C, VAN LOON E E, RAES N, REEMER M, BIESMEIJER J C. Fit-for-purpose: Species distribution model performance depends on evaluation criteria-Dutch Hoverflies as a case study. PLoS ONE, 2013, 8(5): e63708.
[15]	FOURCADE Y, ENGLER J O, RÖDDER D, SECONDI J. Mapping species distributions with MAXENT using a geographically biased sample of presence data: A performance assessment of methods for correcting sampling bias. PLoS ONE, 2014, 9(5): e97122.
[16]	FIELDING A H, BELL J F. A review of methods for the assessment of prediction errors in conservation presence/absence models. Environmental Conservation, 1997, 24(1): 38-49.
[17]	BABAR S, AMARNATH G, REDDY C S, JENTSCH A, SUDHAKAR S. Species distribution models: Ecological explanation and prediction of an endemic and endangered plant species (Pterocarpus santalinus L. f.). Current Science, 2012, 102(8): 1157-1165.
[18]	吴齐, 董树斌, 杨蕾, 亓秀金, 张毓, 杨明琪, 任志河, 刘青昊, 程瑾. 气候变化情景下大花杓兰在中国的适生区预测. 生态学报, 2024, 44(1): 209-223.
	WU Q, DONG S B, YANG L, QI X J, ZAHNG Y, YANG M Q, REN Z H, LIU Q H, CHENG J. Prediction of potential distribution of Cypripedium macranthos under climate change scenarios in China. Acta Ecologica Sinica, 2024, 44(1): 209-223. (in Chinese)
[19]	孙颖, 秦大河, 刘洪滨. IPCC第五次评估报告不确定性处理方法的介绍. 气候变化研究进展, 2012, 8(2): 150-153.
	SUN Y, QIN D H, LIU H B. Introduction to treatment of uncertainties for IPCC fifth assessment report. Climate Change Research, 2012, 8(2): 150-153. (in Chinese)
[20]	LI M Y, HE J, ZHAO Z, LYU R D, YAO M, CHENG J, XIE L. Predictive modelling of the distribution of Clematis sect. Fruticella s. str. under climate change reveals a range expansion during the Last Glacial Maximum. PeerJ, 2020, 8: e8729.
[21]	ZHANG K L, ZHANG Y, TAO J. Predicting the potential distribution of Paeoniaveitchii (Paeoniaceae) in China by incorporating climate change into a MaxEnt model. Forests, 2019, 10(2): 190.
[22]	YAN H Y, FENG L, ZHAO Y F, FENG L, WU D, ZHU C P. Prediction of the spatial distribution of Alternantheraphiloxeroides in China based on ArcGIS and MaxEnt. Global Ecology and Conservation, 2020, 21: e00856.
[23]	陈紫葳, 杜燕, 郭静霞, 杨美青. 基于MaxEnt与ArcGIS的中国角茴香生态适宜性区划研究. 智慧农业导刊, 2024(1): 14-18.
	CHEN Z W, DU Y, GUO J X, YANG M Q. Ecological suitability regionalization of carnelian anise in China Hypecoum erectum based on MaxEnt and ArcGIS. Journal of Smart Agriculture, 2024(1): 14-18. (in Chinese)
[24]	戴凌全, 吴倩, 常曼琪, 任玉峰, 汤正阳, 姜伟, 李翀, 戴会超. 基于最大熵模型的东洞庭湖典型沉水植物生境评价. 生态学杂志, 2024, 43(2): 542-549.
	DAI L Q, WU Q, CHANG M Q, REN Y F, TANG Z Y, JIANG W, LI C, DAI H C. MaxEnt model-based evaluation of habitat of typical submerged plants in East Dongting Lake. Chinese Journal of Ecology, 2024, 43(2): 542-549. (in Chinese) doi: 10.13292/j.1000-4890.202402.002
[25]	HAO Y L, DONG P B, WANG L Y, KE X, HAO X F, HE G, CHEN Y, GUO F X. Predicting the potential distribution of Hypericum perforatum under climate change scenarios using a maximum entropy model. Biology, 2024, 13(6): 452.
[26]	林正雨, 陈强, 邓良基, 李晓, 何鹏, 熊鹰. 四川柑橘适宜分布及其对气候变化的响应研究. 中国生态农业学报, 2019, 27(6): 845-859.
	LIN Z Y, CHEN Q, DENG L J, LI X, HE P, XIONG Y. Response of suitable distribution of Citrus in Sichuan province to climate change. Chinese Journal of Eco-Agriculture, 2019, 27(6): 845-859. (in Chinese)
[27]	林正雨, 陈春燕, 刘远利, 高文波, 曹杰, 刘光辉, 廖桂堂, 何鹏. 基于适宜概率模型的柑橘生产空间模拟变化. 农业现代化研究, 2022, 43(4): 726-737.
	LIN Z Y, CHEN C Y, LIU Y L, GAO W B, CAO J, LIU G H, LIAO G T, HE P. Simulation of citrus production area change based onsuitable probability model. Research of Agricultural Modernization, 2022, 43(4): 726-737. (in Chinese)
[28]	李玲, 肖润林, 陈正法, 莫继荣. 湘赣柑橘园气候环境障碍因子及其防改措施. 农业环境保护, 2000, 19(1): 25-28.
	LI L, XIAO R L, CHEN Z F, MO J R. Climate limiting factors and their control measures on cirtus planting Hunan and Jiangxi province. Journal of Agro-Environment Science, 2000, 19(1):25-28. (in Chinese)
[29]	郑铭洁, 余红伟, 陈志良, 章明奎. 浙西丘陵区柑橘园土壤健康状况及管理对策. 浙江农业科学, 2022, 63(2): 324-329, 362. doi: 10.16178/j.issn.0528-9017.20213154
	ZHENG M J, YU H W, CHEN Z L, ZAHNG M K. Soil health status and management countermeasures of citrus orchards in hilly areas of the Western Zhejiang. Zhejiang Agricultural Sciences, 2022, 63(2): 324-329, 362. (in Chinese)
[30]	陈志敏, 陈晓林, 谭振华, 陈兆星, 谌丹丹, 马岩岩, 郑永强, 易时来, 吕强, 谢让金. 不同产区纽荷尔脐橙橘园果实综合品质评价与适宜区域筛选. 中国农业科学, 2023, 56(10): 1949-1965. doi: 10.3864/j.issn.0578-1752.2023.10.011.
	CHEN Z M, CHEN X L, TAN Z H, CHEN Z X, CHEN D D, MA Y Y, ZHENG Y Q, YI S L, LÜ Q, XIE R J. Comprehensive fruit quality evaluation and suitable areas selection of newhall navel orange in China. Scientia Agricultura Sinica, 2023, 56(10): 1949-1965. doi: 10.3864/j.issn.0578-1752.2023.10.011. (in Chinese)
[31]	周立, 陈品文, 蒲成伟, 何发, 张绩, 周上玲, 杨贵川. 柑橘裂果的主要原因及预防措施研究进展. 现代农业科技, 2022(13): 35-38.
	ZHOU L, CHEN P W, PU C W, HE F, ZHANG J, ZHOU S L, YANG G C. Research progress on main causes and preventive measures of Citrus fruit cracking. Modern Agricultural Sciences and Technology, 2022(13): 35-38. (in Chinese)

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筛选后的环境因子 Screened environment variables	贡献率 Contribution rate (%)	变量意义 Variable significance
年平均气温AAT	22.9	反映年总的热量资源情况 Reflecting the total annual heat
海拔Elevation	15.7	通过温度间接影响柑橘生长 Indirectly affecting citrus growth by affecting the temperature
全磷TP	13.8	磷肥能降低果实酸度，提高固酸比 Phosphate fertilizer can reduce fruit acidity and improve solid-acid ratio
pH	10.4	偏酸（pH<4.5）和偏碱（pH>8.5）不适于柑橘生长 Neither pH<4.5 nor pH>8.5 is suitable for citrus growth
年平均相对湿度AARH	7.0	空气水分含量影响柑橘生长发育和病虫害发生 Air moisture content can affect citrus growth and developmentand the occurrence of diseases and pests
粉粒量Silt content	5.7	影响土壤的肥力保肥供肥、通气排水能力，间接影响柑橘生长 Affecting fertilizer supply, ventilation and drainage, and indirectly affecting citrus growth
年降水量ANP	4.6	年总的水分条件 Total annual moisture conditions
年日照时数ASD	4.3	日照时间的长短影响柑橘的光合作用 Affecting the photosynthesis of citrus
秋季降水量AUP	4.2	作物生长时的水分供应情况，关系果实成熟和品质 Precipitation from July to September affects fruit maturity and quality
交换性钙ECA	4.1	提高果实糖分和维生素含量，减少裂果 Increasing fruit sugar and vitamin content, reducing fruit cracking
全钾TK	3.7	钾肥可以提高单果重，增加果皮厚度，提高可溶性固形物含量 Potassium fertilizer can increase single fruit weight, peel thickness and soluble solid content
有机质OM	3.6	影响柑橘树基础产量、果实品质 Affecting the base yield and fruit quality of citrus

环境因子 Environmental variables	优势区Advantageous area		适宜区Suitable area		不适宜区Non-suitable area
环境因子 Environmental variables	范围 Range	平均值±标准差 Mean±Standard deviation	范围 Range	平均值±标准差 Mean±Standard deviation	范围 Range	平均值±标准差 Mean±Standard deviation
年平均气温AAT (℃)	15.5-18.3	17.6±0.3	15.5-18.3	17.7±0.4	15.5-18.3	17.8±0.4
海拔Elevation (m)	368-833	439±45	356-833	436±50	352-825	416±68
全磷TP (g·kg^-1)	0.1-1.4	0.5±0.2	0.1-1.4	0.5±0.2	0.1-1.4	0.6±0.2
pH	3.6-8.7	5.4±1.4	3.6-8.7	5.5±1.3	3.6-8.7	5.7±1.3
年平均相对湿度AARH (%)	77.5-81.5	79.1±0.6	77.4-81.5	78.9±0.7	77.4-81.5	78.4±0.8
粉粒量Silt content (%)	8.5-59.5	41.8±5.7	8.5-59.5	41.0±6.3	3.5-59.5	40.3±7.4
年降水量ANP (mm)	1141-1585	1440±87	1134-1599	1404±101	1134-1610	1354±103
年日照时数ASD (h)	1270-1394	1348±25	1268-1395	1350±29	1268-1395	1338±34
秋季降水量AUP (mm)	388-400	393±3	388-399	394±49	388-399	395±75
交换性钙ECA (mg·kg^-1)	0.1-25.1	6.2±4.9	0.1-26.8	6.3±4.5	0.1-29.3	7.1±4.4
全钾TK (g·kg^-1)	4.0-33.5	13.6±4.3	4.0-33.5	14.1±4.2	4.0-33.5	14.6±4.2
有机质OM (g·kg^-1)	5.3-50.1	18.8±5.9	2.6-56.1	18.9±6.3	5.3-56.1	21.2±7.8

乡镇 Town (Street)	优势区 Advantageous area		适宜区 Suitable area		不适宜区 Non-suitable area
乡镇 Town (Street)	面积 Area (hm²)	比例 Proportion (%)	面积 Area (hm²)	比例 Proportion (%)	面积 Area (hm²)	比例 Proportion (%)
崇礼镇Chongli Town	8.8	0.6	813.9	56.1	628.6	43.3
大石桥街道Dashiqiao Street	0	0	0	0	17.4	100.0
多悦镇Duoyue Town	830.0	21.4	2739.8	70.7	303.4	7.8
复兴镇Fuxing Town	1.7	0.2	345.4	39.7	522.3	60.1
富牛镇Funiu Town	432.4	13.5	2188.4	68.4	576.5	18.0
秦家镇Qinjia Town	1294.9	29.2	2871.9	64.8	265.3	6.0
三苏镇Sansu Town	2764.2	43.0	3399.5	52.9	264.2	4.1
尚义镇Shangyi Town	231.1	9.9	1653.6	71.0	443.8	19.1
思蒙镇Simeng Town	280.0	8.2	2018.8	59.5	1094.8	32.3
松江镇Songjiang Town	3.5	0.6	299.9	47.5	328.1	52.0
苏祠街道Suci Street	0	0	0	0	2.9	100.0
太和镇Taihe Town	182.9	14.0	917.1	70.4	202.2	15.5
通惠街道Tonghui Street	0.1	0.2	0	0	55.5	99.8
万胜镇Wansheng Town	1112.2	33.2	2013.6	60.2	220.8	6.6
修文镇Xiuwen Town	1011.3	31.2	2009.8	62.0	219.2	6.8
永寿镇Yongshou Town	0	0	7.1	6.8	96.4	93.2
合计Total	8153.1	23.5	21278.8	61.4	5241.4	15.1

Suitability Evaluation of Late Maturing Citrus in Dongpo District, Meishan City, Sichuan Province Based on Maximum Entropy Model (MaxEnt) and Geographic Information System (GIS)

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[5]	WANG Qin, TU Chang-Chun, HUANG Bao-Xu, XU Lu, GAI Hua-Wu, FAN Xue-Zheng, GUO Huan-Cheng, XU He-Min, LI Jin-Hua, ZHAO Qi-Zu, NING Yi-Bao, ZHENG Ran, SHEN Qing-Chun. 猪瘟 \|猪瘟病毒 \|流行病学 \|地理信息系统 \|数据库 [J]. Scientia Agricultura Sinica, 2013, 46(11): 2363-2369.
[6]	DUAN Ju-Qi, ZHOU Guang-Sheng. Climatic Suitability of Double Rice Planting Regions in China [J]. Scientia Agricultura Sinica, 2012, 45(2): 218-227.
[7]	,,. Potential Distribution of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) in China by Using Combined CLIMEX and GIS Tools [J]. Scientia Agricultura Sinica, 2006, 39(03): 525-529 .