A new bird record in China： Moustached Warbler (Acrocephalus melanopogon) and its song characteristics

Moustached Warbler （Acrocephalus melanopogon）, belonging to the genus of Acrocephalus and the family of Acrocephalidae, breeds widely but locally in the warm temperate regions from Northwest Africa and eastern Iberian Peninsula to eastern Kazakhstan. However, this species has never been scientifically recorded in China. On 22 April 2016, a Moustached Warbler was observed in Ulanbuy wetland （43°36′N, 87°43′E; 1114 m a.s.l.）, Urumqi, Xinjiang of China. This was the first photography-confirmed record of Moustached Warbler in China. As Moustached Warbler is a songbird, the songs were then recorded on 18 May 2016 using a Sony PCM D-100 recorder and the song characteristics were analyzed using Avisoft-SASLab software. The result showed that the mean maximum frequency of song strophes was 6.64 （±0.47） kHz and the mean minimum frequency of song strophes was 1.72 （±0.14） kHz. This study could considered as a supplement of the checklist of birds in China.

A study of song characteristics and hearing in the bushcricket Gampsocleis gratiosa

The structure, power spectrum and temporal parameters of the calling song of the bushcricket Gampsocleis gratiosa were studied with acoustic analysis techniques. The bushcricket uses an elytro-elytral mechanism in sound production: the denticulated vein ( file ) on the under-surface of the left elytron is rubbed by the insider edge of the right elytron ( plectrum ). The file-train of pulses is composed of one elytra-opening pulse and 6 - 7 elytra-closing tooth pulses. The power spectrum of the song covers a wide frequency band. The acoustic energy is mainly distributed over the frequency range between 3 and 35 kHz. The predominant peak lies near 7.5 kHz and the next one around 4.0kHz. The song intensity is measured of about 105 dB SPL at a distance of 10 cm from the animal. The temporal parameters of the song are dependent on the ambient temperature. Three-dimensional digital spectrograms of the song show its dynamic changes of the energy peaks. The bushcricket is very sensitive to acoustic stimuli and its thresholds are less than 30 dB SPL in the frequency range from 7 to 18 kHz, which corresponds to dominant energy zone. The auditory neurons of the bushcricket can code the temporal parameters of the calling songs.

Reconstruction of Lu-level cropland areas in the Northern Song Dynasty （AD976-1078）

Based on data on taxed-cropland area and on the number of households in historical documents, a probabilistic model of cropland distribution and a cropland area allocation model were designed and validated. Cropland areas for the years AD976, 997, 1066, and 1078 were estimated at the level of Lu（an administrative region of the Northern Song Dynasty）. The results indicated that（1） the cropland area of the whole study region for AD976, 997, 1066, and 1078 was about 468.27 million mu（a Chinese unit of area, with1 mu=666.7m2）, 495.53 million mu, 697.65 million mu, and 731.94 million mu, respectively. The fractional cropland area（FCA） increased from 10.7% to 16.8%, and the per capita cropland area decreased from 15.7 mu to 8.4 mu.（2） With regard to the cropland spatial pattern, the FCA of the southeast, north, and southwest regions of the Northern Song territory increased by 12.0%, 5.2%, and 1.2%, respectively. The FCA of some regions in the Yangtze River Plain increased to greater than 40%, and the FCA of the North China Plain increased to greater than 20%. However, the FCA of the southwest region（except for the Chengdu Plain） in the Northern Song territory was less than 6%.（3） There were 84.2% Lus whose absolute relative error was smaller than 20% in the mid Northern Song Dynasty. The validation results indicate that our models are reasonable and that the results of reconstruction are credible.