ALBERT

Description: In order to understand the research hotspots and the development directions in the field of vulnerable karst environment, we undertook bibliometrics citation analysis on 5425 contributions to the literature written in the range from 1991 to 2017 based on the “Web of Science” core collection citation index database. Hopefully, this work will help to set up a scientific foundation for further studies. This research considered the following factors: keywords frequency, influence of author, research hotspot, reference citation network, research institution and the evolution of research topic. It was revealed that the research interests were focused on water, cave, and soil environments and implicated trends switching from a water environment to cave and eco-environment and from ecological restoration and rehabilitation to karst rocky desertification. A European-American-Chinese centered cooperation network has shown its initial form. This research will offer researchers a bird’s eye view of the global vulnerable karst environment and point out the directions of further study.

Description: A homemade portable no-blind zone laser detection and ranging (lidar) system was designed to map the three-dimensional (3D) distribution of aerosols based on a dual-field-of-view (FOV) receiver system. This innovative lidar prototype has a space resolution of 7.5 m and a time resolution of 30 s. A blind zone of zero meters, and a transition zone of approximately 60 m were realized with careful optical alignments, and were rather meaningful to the lower atmosphere observation. With a scanning platform, the lidar system was used to locate the industrial pollution sources at ground level. The primary parameters of the transmitter, receivers, and detectors are described in this paper. Acquiring a whole return signal of this lidar system represents the key step to the retrieval of aerosol distribution with applying a linear joining method to the two FOV signals. The vertical profiles of aerosols were retrieved by the traditional Fernald method and verified by real-time observations. To effectively and reliably retrieve the horizontal distributions of aerosols, a composition of the Fernald method and the slope method were applied. In this way, a priori assumptions of even atmospheric conditions and the already-known reference point in the lidar equation were avoided. No-blind-zone vertical in-situ observation of aerosol illustrated a detailed evolution from almost 0 m to higher altitudes. No-blind-zone detection provided tiny structures of pollution distribution in lower atmosphere, which is closely related to human health. Horizontal field scanning experiments were also conducted in the Shandong Province. The results showed a high accuracy of aerosol mass movement by this lidar system. An effective quantitative way to locate pollution sources distribution was paved with the portable lidar system after validation by the mass concentration of suspended particulate matter from a ground air quality station.