The vegetation features and biomass of sandy rangeland in semi-arid area of Yanchi County, Ningxia were studied by means of plot investigation methods since 1991.

采用样地调查法，对盐池县1991年以来不同时期的老封育区、新封育区和对照区进行半干旱沙地草场的植被特征及其生物量比较研究。

youdao

Afghan officials said they were held as part of an investigation into an alleged plot to kill the governor of Helmand province.

VOA: standard.2010.04.12

Clive Goodman, the only News of the World reporter jailed for hacking, was arrested in the middle of a hugely successful investigation into a plot to bring down transatlantic airliners.

BBC: Leveson's police grilling only the beginning

Chertoff told ABC's This Week, the flexibility of British law helped the investigation into this alleged plot.

NPR: U.S. Clarifies Security Rules for Air Travel

But CNN has learned that the inmate has failed a number of lie detector tests regarding the details -- described by some sources close to the investigation as vague -- of the plot.

CNN: Police doubt authenticity of Jeb Bush killing plot