In this paper, Web of Science (a database) is used to retrieve related literature in the field of heavy metal pollution in desert. CiteSpace is used to make a quantitative and qualitative evaluation on the literature in the field on the basis of a brief analysis on the research status, research focus, and evolution process in the field. Through CiteSpace visual analysis, a comparative analysis is given on related literature in terms of annual number of published papers, author groups, and their countries and regions, journals, publishing institutions, highly cited papers, research focuses, and burst terms, so as to explore the research status and future development trend of the field on a global scale. The results are shown as follows: (1) The literature in the field was originally published in 2000; the number of published papers increased steadily. The literature was mostly published on high-quality journals, the USA topped in terms of the number of published papers, and the research results achieved by developed countries had a greater influence. Chinese Acad Sci topped with the highest centrality and most published papers, which have made outstanding contributions to the field and occupy a leading position in the field. However, the fact is that there lacks communication and cooperation among research institutions. The most influential journal is Science of the Total Environment. (2) The hot research words in the field are as follows: heavy metal, soil, pollution, lead, desert, cadmium, and microelement. (3) In the field, burst terms have transformed from atmospheric deposition, biomonitoring, and phytoremediation to trace element, stream sediment, street dust, and water quality, and finally transformed to river and sediment. New words keep emerging in the research, and more and more attention is paid to the issue of heavy metal pollution in river sediment, which will be a future research hotspot in the field.
Agricultural drought differs from meteorological, hydrological, and socioeconomic drought, being closely related to soil water availability in the root zone, specifically for crop and crop growth stage. In previous studies, several soil moisture indices (e.g., the soil moisture index, soil water deficit index) based on soil water availability have been developed for agricultural drought monitoring. However, when developing these indices, it was generally assumed that soil water availability to crops was equal throughout the root zone, and the effects of root distribution and crop growth stage on soil water uptake were ignored. This article aims to incorporate root distribution into a soil moisture‐based index and to evaluate the performance of the improved soil moisture index for agricultural drought monitoring. The Huang‐Huai‐Hai Plain of China was used as the study area. Overall, soil moisture indices were significantly correlated with the crop moisture index (CMI), and the improved root‐weighted soil moisture index (RSMI) was more closely related to the CMI than averaged soil moisture indices. The RSMI correctly identified most of the observed drought events and performed well in the detection of drought levels. Furthermore, the RSMI had a better performance than averaged soil moisture indices when compared to crop yield. In conclusion, soil moisture indices could improve agricultural drought monitoring by incorporating root distribution. 相似文献