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Qionghai Lake is the second largest freshwater lake in Sichuan Province. Invasive plants have damaged the ecological balance of Qionghai Lake. Regular investigation and monitoring of invasive alien plants in Qionghai Lake in autumn and winter. Study structural changes and trend changes. Mapping dynamic monitoring of the distribution of invasive plants. Upon investigation, a wide range of invasive plants with a large rits are Eupatorium Adenophorum, Lantana camara, Bidens alba(L.) DC, Alternanthera philoxeroides, Pharbitis purpurea(L.) Voisgt and Oxalis corniculata L. The introduction of the Tagetes erecta L as Ornamental plants, the proliferation occurred because of mismanagement. The number of Mirabilis jalapa L. is very small. Analysis of the way of invasive alien plants into the Qionghai Sea and the measures of prevention and control.

The small carrier wavelength at millimeter wave (mm-wave) frequencies features a large number of co-located antennas. Wireless networks with directional antennas using beamforming at mm-wave also have potential to provide an enhanced security in the vehicular communication system. Large bandwidth of mm-wave can provide auto drive and safety linked functionalities, However, safety and efficiency of the vehicular transportation system can be jeopardized by many kinds of attacks by eavesdroppers, physical layer security can work as an extra layer of security for wireless communication systems. To secure communication in-between Vehicles, an Analog precoding based physical Layer technique for mm-wave vehicular communication systems is presented in the paper. The proposed technique works by exploiting large Antenna arrays at millimeter waves and provide a secure directional transmission with low power consuming phase shifters and single Radio Frequency Chain. Larger antennas arrays are split into two subsets, one for transmission of data and another for generating noise. The proposed technique offers improved coherent transmission at the legitimate receiver and by introducing artificial noise to the eavesdroppers at random directions. This outcome in low SNR for the eavesdroppers, hence hacking information becomes extremely difficult. Numerical and Simulation results show the superior performance of the proposed technique compared to traditional physical layer security technique and conventional array technique.