The Prosopis koelziana genus, a member of the Fabaceae family, is crucial to the ecology and economy of arid areas. It is commonly used to restore deserts, forests, and degraded soil with low fertility and high salt concentration. However, recent studies found that the seedlings of P. koelziana are highly susceptible to salinity stress despite having a high tolerance to it. To address this issue, an experiment was conducted to determine if plant growth-promoting rhizobacteria (PGPR) pretreatment and biochar application could enhance the seedlings' tolerance to saline conditions. The research showed that salinity stress decreased seedling growth but increased proline content, soluble sugar content, and antioxidant enzyme activity. Na+ ions increased in plants under salt stress, while K+ ions decreased. The results indicated that the pretreatment of plants with biochar and bacteria increased the fresh weight of seedlings by about 23%, 58%, and 50% in 200, 400, and 600 mM NaCl, respectively, compared with non-pretreated plants. Biochar and bacteria application also increased the proline content by about 62%, 46%, 32%, and 45% in 0, 200, 400, and 600 mM NaCl. This experiment showed that bacteria and biochar pretreatment of plants reduced oxidative stress and sodium uptake (20%, 28%, and 10% decrement of root Na uptake in 200, 400, and 600 mM NaCl). Therefore, these two bio stimulators should be used together for more significant effects on the salinity mitigation of P. Koelziana seedlings and the production of resistant seedlings that have a high ability to transfer to the field.
季冻区路基在冻融作用下常常发生冻胀、融沉等病害,其中路基土的温、湿度水平是致灾的重要因素。针对现有监测手段单一,路基温、湿度全时空监测困难等问题,利用远程无线传输技术,设计了一种基于GPRS(通用分组无线服务)通信技术的季冻土路基温、湿度双参数监测系统,可以实时监测路基温、湿度变化。系统采用土壤专用的温、湿度传感器作为采集终端;以STC89C52单片机作为主控制器,通过编辑AT指令控制GPRS连通网络和数据收发,实现温、湿度数据远程传输和存储。经实际验证该系统采集精度高、稳定可靠、操作方便,可实现对季冻土路基内部温、湿度的实时无损监测。
设计了一种新型的高原冻土监测系统。采用ARM7内核的MCU进行控制,并基于IPv6协议利用IPv6技术和GPRS技术相结合的方式,建立了可自组网的无线传感器网络,实现了对指定区域环境参数的实时监测。系统使用了多个土壤水分传感器、温度传感器、二氧化碳传感器、氮气传感器对高原冻土环境进行全方位实时观测。各监测点将数据通过基于IPv6的无线网络传送给汇聚节点,汇聚节点再通过GPRS网络将数据传送给监控中心。监控中心可以对数据进行记录和分析,更好地指导环境保护和建设工作。
针对冻土地温远程自动监测的实际需求和实施条件,提出基于GPRS的冻土地温远程监控系统的体系结构和组成模块,进行硬件原理设计、GPRS传输模块数据接口及相关传输协议设计,并分析采集数据。经应用证明,系统可满足冻土地温长期自动观测的需要。
