Experimental studies were conducted at the yucheng comprehensive experimental station of the chinese academy of sciences during the period from march to june in 2003 . respiration of a pulverous sandstone soil was studied under cultivation of winter wheat over a growth season . soil ch4 was measured by the static - chamber method combined with gas chromatography ( gc ) technique . the results indicated that the soil of winter wheat field in rapid growth season is a weak sink of ch4 本文利用静态箱气相色谱( gc )分析的方法，在中国科学院禹城综合试验站，对华北平原冬小麦生长旺季期间麦田土壤中ch _ 4气体通量进行了测定，试验起止时间为2003年3 6月，得出华北平原典型冬麦田土壤是大气ch _ 4的弱吸收汇。
Hebei o genoa bicycle parts limited , located in north china plain , south east of jingguang railway 54 km west of beijing - kowloon railway , 60 km , bicycle parts city west km transport facilities , the environment and elegant , is the bicycle accessories industry manufacturing company , which produces the australian yafeng licensing saddles , car crash , pedal , axial and other accessories , a total of five series of over 60 varieties 河北澳亚达自行车零件有限公司，位于华北平原南部，西距京广铁路54公里，东距京九铁路60公里，中国自行车零件城西侧4公里处，交通便利，环境优雅，是国内自行车配件行业的专业制造公司，主要生产澳亚峰牌鞍座、车筐、脚蹬、中轴及其它配件共五大系列六十多个品种。
Six sound mountainous region area is located within the boundaries of the hebei province qinhuangdao lulong shimen town , is located northeast our country huabei pingyuan the beijing and tianjin tang qin economy to move in a circle the area , east is near bohai sea , west depends on luanhe river , north the pillow mt . yanshan - odd arteries , south depend on 205 federal highways and the jingshan railroad parallel transportation skeleton line ; by a series of lianshan , the rivers , the village are composed , about area approximately 8 square kilometers 六音山地区位于河北省秦皇岛市卢龙县石门镇境内，位于我国华北平原东北部京津唐秦经济环行地区，东临渤海，西依滦河，北枕燕山余脉，南靠205国道与京山铁路并行交通干线；由一系列连山、河流、村落组成，面积约8平方公里左右！
Monthly rainfall data from 1951 to 1995 for june , july and august in 13 meteorological stations of the north china were used for accounting z index and discussing serious flood and drought featureas in these months . serious flood mainly happened in july and august , and sevious drought mainly happened in august . there were more flood in 1950 ' s to 1960 ' s and more drought since 1970 ' s in the north china . meanwhile , the deeper trough which covered the regions from the ural mts . to the balkhash lake play an important role in serious rainstom in rainy season in the north china . there often happened serious flood ( drought ) when the northwester pacific subtropical high was by west and north ( east and south ) , and the sea surface temperature in the equatorial central and eastern pacific was mainly in dropping ( raising ) stage 利用华北平原地区的13个站点, 45年（ 1951 1995 )的降水资料,对夏季4个时段（ 6月、 7月、 8月、 6 8月）进行了z指数计算,确定了该地区各个时段的严重涝年和严重旱年.发现华北地区雨季的严重洪涝主要集中在7 , 8月,严重干旱则主要发生在8月,并可明显看出由50 60年代的多水期向70年代中期以后的少水期的转变,另外,乌拉尔山到巴尔喀什湖附近的低压槽加深和西北太平洋副热带高压的北抬,对华北地区雨季持续性暴雨的产生起着决定性的作用.严重洪涝年的夏季（ 6 8月） ,西北太平洋副热带高压偏西、偏北,赤道东太平洋海温多处于下降阶段;严重干旱年西北太平洋副高偏东、偏南,赤道东太平洋海温则处于上升阶段
