摘要
为高效开发利用喀斯特水资源,解决石漠化农村地区干旱缺水问题。根据水资源供需平衡理论,以毕节撒拉溪示范区朝营小流域为例,通过野外勘察与定点监测,分析小流域水资源赋存状况以及干旱情景下的响应特征,结果显示:研究区水资源总体丰富,年平均降雨量892.5mm,折合降雨量7 699.5万m3。多年平均地表径流深为498.2mm,全年地表径流量约4 298.1万m3。流域内大小泉点共118处,全年流量达81.57万m3;时空分布不均,时间上5—9月降水总量占年降水总量57.6~87.3%,10—4月降水偏少,仅占12.7%~42.7%,降水季节性差异明显。泉水雨季总流量为45.64L/s,枯季仅12.35L/s,两者相差3.7倍。空间上以流域北部地区(茅坪村)泉点出露数量较多且流量最大,占整个流域水资源总量35%左右,中部地区(朝营村等地)出露泉点数量较少;极度干旱情景下,流域内67%泉点断流,水池(水窖)干涸,水利工程失效,部分地区人均日可用量仅为2L,与有关部门规定的人均日用水量35L的最低标准相差达94.3%。极度干旱环境下作物需水缺口为28.37万m3。因此,采取屋面集雨、屋檐集雨、收集坡面径流以及表层岩溶水综合开发利用等方式,实现水资源的开发利用与优化调度,建立基于时间以及空间尺度的极度干旱水资源应急调控机制,是保障地区用水安全的重要方式。
Taking Caoying catchment of Salaxi demonstration area in Bijie as an example,water resources occur- rence state of the small catchment and the response characteristics in drought conditions were analyzed through field investigation and fixed point monitoring to efficiently develop and utilize karst water resources and solve the problem of drought and water shortage in karst rocky desertification rural areas. The results show that：Water resources in the research area are overall rich. The mean value of annual rainfall is 892.5 mm, converting into 76. 995 million m3 in the catchment. The multi-year average runoff depth is 498.2 mm. The annual surface runoff is about 42. 981 million m3. The total number of springs in the catchment is ll8,and the annual flow of which is 0. 815,7 million m3. The space-time location of the precipitation is not well balanced. In time, the percentage of rainfall from May to Septem-ber varies from 57.6 to 87.3 %, while the rainfall of the seven months from October to April is less, and the per- centage of which varies is just from 12. 7 % to 42. 7 %, showing a significant seasonal difference. The total flow rate of the spring water is 45.64 L / s,while the dry season is only 12.35 L / s,and the difference is 3.7 times. In space, the springs number and flow in the north area （ Maoping village） of the catchment is more than other areas, and the water resource of this re^ion is about 35 % of the whole of the catchment,while the springs in the middle ar- ea（ Caoying village, etc. ）is less. In case of extreme drought ,67 % springs of the catchment cut off, pools（cisterns） dry ,water conservancy projects lose efficacy, and per capita water availability per day is only 2 L/ d, which is 94. 3 % less than the 50 L / d minimum standards of provisions of the relevant departments. Under the extremely dry conditions ,the crop water demand gap is 0. 283,7 million m3. Therefore, to realize the development and utiliza- tion as well as optimal operation of water resources, we build the emerg
出处
《贵州科学》
2016年第3期39-45,共7页
Guizhou Science
基金
贵州省科技计划重大专项"国家喀斯特石漠化防治工程中心关键技术研发与示范"(黔科合重大专项字[2014]6007号)
关键词
喀斯特石漠化
农村水资源
开发利用
应急调控
karst rocky desertification
rural water resources
development and utilization
emergency control
