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【Objective】The study aimed to analyze the situation of safe utilization of farmland based on CiteSpace, so as to provide reference basis for sustainable use of cultivated land resource in China.【Method】CiteSpace VI was used to analyze the information of 1419 literatures in the field of farmland safe utilization from 2000 to 2022 from China National Knowledge Infrastructure（CNKI）. Price theory was used to calculate the core author group, and the conservation and utilization situation of cultivated land resources in China was evaluated.【Result】From 2000 to 2022, the problem of heavy metal pollution in farmland in China had become more and more serious. The number of annual publications in the field of safe utilization research had been rising rapidly in a wavy fashion. Since 2003, experts and scholars had paid more and more attention to this research field. Analysis of the main research strength results showed that the University of Chinese Academy of Sciences, Institute of Soil Sciences of Chinese Academy of Sciences, Agro-environmental Protection Institute of Ministry of Agriculture and Social Affairs, Institute of Geographic Sciences and Natural Resources Research of Chinese Academy of Sciences and College of Resources and Environment of Yunnan Agricultural University were the top 5 institutions of publishing articles, with 70, 63, 36, 35 and 19 articles published respectively. However, other research institutions had low connectivity density and weak cooperation basis. Chen Tongbin, Song Bo, Luo Yongming, Zhan Fangdong and Wu Longhua were the top 5 authors with 24, 20, 17, 15 and 15 articles published respectively, but the centrality of the top 10 authors was low, ranging from 0 to 0.06. Results of keyword co-occurrence and cluster analysis showed that source resolution, passivation remediation, passivation agent, biochar, cadmium pollution, wheat and health risk emerged keywords in recent years, and the intensity of the emergence was 5.30, 5.19, 4.57, 4.75, 4.64, 3.34 and 3.81, respectively. The above keywords related topics were the main research directions of current and future research fields of farmland safety use; Phytoremediation, safe production of crop and heavy metal pollution and risk assessment of farmland soil were the trending research point of many experts and scholars.【Conclusion】From 2000 to 2022, the problem of heavy metal pollution in farmland in China has become increasingly serious. The number of annual articles published in the field of farmland safety utilization has risen rapidly in a wavy way on the whole. However, the centrality of the top 10 authors in the number of articles published is low, and the connection density between most research institutions is low, and the basis for cooperation is weak. Therefore, it is suggested to further strengthen the collaborative innovation research among core authors and promote the cooperation and exchange between research institutions, so as to promote the rapid development of farmland safe use research, promoting the protection and utilization of cultivated land resources in China. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to study the occurrence form of cadmium (Cd) accumulation in soil aggregates of Cd-contaminated brown calcareous soil matrices of paddy fields in the Karst area of northwestern Guangxi, and to provide data reference for safe rice production in this type of Cd-contaminated paddy fields in the region. 【Method】The sampled soil aggregates were separated into five aggregates as ＞ 2.000 mm, 1.000-2.000 mm, 0.050-1.000 mm, 0.074-0.250 mm and ＜0.074 mm, the composition of soil aggregates particle size, Cd content of different particle size aggregates and their main occurrence patterns from 0-20, 20-30, 30-50 and 50-80 cm depth profiles in the Karst area of northwest Guangxi were studied.【Result】The proportion of 0.250-1.000 mm size aggregates in each profile was stable, above 30.00%, with no significant difference between profiles (P＞0.05), the proportion of ＞2.000 mm size aggregates in the 0-20 cm soil profile (tillage layer) was the largest (40.20%), and as the depth of the profile increased, the proportion of ＞2.000 mm size aggregates decreased rapidly, and the proportion of ＜0.250 mm size aggregates showed a gradual increasing trend. Analysis of the Cd content of agglomerates of different particle sizes showed that, in 0-20, 20-30 and 30-50 cm soil profiles, Cd was mainly enriched in ＞2.000 mm particle size aggregates, with contents as high as 2.22, 1.66 and 0.95 mg/kg, respectively, and in the 50-80 cm soil profile, Cd was mainly enriched in 1.000-2.000 mm particle size aggregates. ＞2.000 mm particle size aggregates contributed most to the whole soil Cd content in the 0-30 cm soil layer. The occurrence form of Cd in the aggregates at different profile depths showed obvious differences, the proportion of Cd in aggregates of all particle sizes in the 0-20 cm profile was mainly in the organic matter binding state, with the smallest proportion of Cd in the exchangeable state (except for ＜0.074 mm particle size aggregates), and the proportion of Cd in the exchangeable state in the aggregates increased greatly with the increase of the depth of the profile, when the profile depth was increased to under 30 cm, the Cd in the aggregates mainly existed in carbonate bound state, and with minimal content in the residue lattice state.【Conclusion】In the typical Cd-contaminated brown calcareous soil matrices of paddy fields in the Karst area of northwestern Guangxi, the Cd is mainly enriched in aggregates of ＞2.000 mm and 1.000-2.000 mm particle size, the Cd in the aggregates of each particle size in the 0-20 cm tillage soil is mainly in the form of organic matter bound state, and with the smallest proportion in the form of exchangeable state. With the increase of the profile depth, the proportion of exchangeable Cd increases greatly, while the proportion of Cd in the stable form decreases significantly. Therefore, in the actual production process, it should focus on improving the content of large particle size soil aggregates and avoiding excessive intensive ploughing and deep tilling, reducing the exchangeable state Cd content in the ploughed soil, and ultimately reducing the risk of excessive Cd in rice during rice production. [ABSTRACT FROM AUTHOR]