水保所知识产出(1956---)知识库

东北黑土区是世界仅存的三大黑土区之一，位于该区北部的松花江流域在东北乃至全国国民经济中占有重要地位。近年来，由于受人类对土地过度垦殖及不合理耕作的影响，水土流失正在成为制约该区粮食生产和耕地可持续利用的主要因素。本文以松花江流域为研究对象，利用降水、径流、输沙资料、土地利用变化等历史资料，采用现代数理统计及小波分析等方法，分析了松花江流域降水量以及主要水文站实测径流和输沙量的历史变化过程、演变趋势、空间分布特征及水沙对人类活动的响应，主要研究进展如下：
1．松花江流域降水量的空间分布特征
松花江流域的年均降水量一般在400～700mm之间，降水呈现自东南向西北递减的趋势，降水量最少的地区位于嫩江下游。流域大部分地区年降水量的变异系数在0.20～0.26之间，降水资源量较稳定。扎兰屯站-江桥站-通榆站一线以西，变异系数大于0.26，降水量年际变化相对较大。
2. 松花江流域径流量的时间变化特征
松花江流域所选取水文站的径流深多年平均值在49.4～221.6mm之间，极值比在4.6～55.1之间，变异系数在0.34～0.88之间，其中洮南站的年际变化最大。采用Mann-Kendall方法对流域内所研究的水文站的年径流深进行趋势检验，结果表明：各水文站的年径流深从不同年份开始均有下降趋势，其中大赉、哈尔滨、佳木斯站径流深的下降趋势显著，兰西站的下降趋势达到了极显著水平。大赉、哈尔滨、兰西和佳木斯站有两个突变点，且均发生在1960’s和1990’s。流域内所研究的水文站的径流深阶段性特征较为明显，且阶段性特征中拐点出现位置大体表现为支流早于干流，上游早于下游。除兰西站外，其余各站径流序列的主周期基本一致。
松花江流域所选取的水文站的径流在日历年内具有双峰型特征，径流深在8月左右最大，2月最小。采用Mann-Kendall方法检验，流域各站点月径流量及年径流量整体有减少趋势。年内分配的不均匀度表现为支流>干流，嫩江流域>松花江干流>第二松花江。库漠屯、阿彦浅、扶余、长江屯站的早春季节径流量偏枯，江桥、洮
南、大赉、哈尔滨、兰西、佳木斯站晚春季节径流量偏枯。
3. 松花江流域输沙量的年际变化特征
江桥和哈尔滨站输沙量的最大值发生在1998年（分别为1240万吨、1170万吨），佳木斯站发生在1994年（3970.4万吨），三个站的最小值均发生在1979年（依次为27.0万吨、152.0万吨、211.3万吨）。哈尔滨站输沙量的变异系数最小，其次是佳木斯站，江桥站最大。江桥和佳木斯站的输沙量有增加趋势，但增加趋势不显著；哈尔滨站输沙量呈显著的下降趋势，且在1978年和1994年发生了两次突变。江桥和佳木斯站输沙量距平累积变化有较好的一致性。
4. 松花江流域水沙演变及其对人类活动的响应
以哈尔滨站为代表，分析了哈尔滨站1955～2005年水沙序列演变及其对人类活动的响应。哈尔滨站1955～2005年的面雨量、径流深和输沙量序列主周期基本一致且均存在28a、17a、7a左右的多时间尺度特征。在7a时间尺度上，20世纪50～60年代，降水、径流和输沙量序列的曲线变化基本同步。20世纪70年代，由于大规模人口迁入，以及对土地的不合理开发等导致了三条曲线发生紊乱，80年代后黑土地综合治理措施的实施使得三条曲线重新趋于一致。水沙丰枯变化及奇异点判断与时间尺度有密切关系，离开时间尺度的变化趋势是毫无意义的。

The Songhua River is located in the north of black soil zone in Northeast China, which is the world's only remaining one of the three major black soil zones, and the Songhua River plays an important role in the national economy. In recent years, by human excessive reclamation of land and unreasonable farming, soil erosion is becoming a constraint factor in sustainable use of arable land and food production in Northeast China. In this paper, the Songhua River as the research object, based on the precipitation, streamflow, sediment transport series data, using modern mathematical statistical test methods and wavelet method, analysis of precipitation, streamflow and sediment transport variatation and its response to human activities. The main conclusions are as follows:
1. Analyzed the precipitation spatial variability.
In Songhua River, the average annual precipitation from 1959~2008 varied generally 400~700mm, and it declined from southeast to northwest, in which there was the least precipitation of downstream of Nen jiang. Annual precipitation coefficient of variation was small in Songhua basin, and it changes between 0.20 and 0.26 in most areas, so precipitation was stable in this basin. The west of the line Zhalantun-Jiangqiao-Tongyu weather station coefficient of variation was greater than 0.26, so the west of line of annual precipitation change was more larger than other areas.
2.Analyzed the temporal variation of the streamflow.
The average streamflow depth of hydrological stations selected in Songhua River was between 49.4 mm and 221.6mm, and the extreme ratio was between 4.6 and 55.1, and the coefficient of variation between 0.34 and 0.88, in which the annual variation of Taonan station was the largest. Analyzed streamflow trends of hydrological stations selected with Mann-Kendall in Songhua Basin, and the results showed that the streamflow decreased from different years, in which the streamflow of Dalai, Harbin, Jiamusi hydrological station decreased significantly, and the downward trend of Lanxi station reached a significant level. There were two abrupt change points in Dalai, Harbin, Lanxi, Jiamusi, and all occurred in the 1960's and 1990's. Streamflow stage characteristics of the
basin was obvious, and the inflection point’s positions in stage characteristics were tributaries earlier than main stream, and upstream earlier than downstream. Except Lanxi, the primary cycles of streamflow of other hydrological stations consistent.
There was bimodal variation of streamflow of hydrological stations selected in a calendar year in Songhua Basin. The streamflow in August was about the most, while the streamflow in February was the least. By Mann-Kendall, monthly and yearly streamflow showed decreasing trend in Songhua Basin. The streamflow in a calendar year was uneven, the uneveness of tributaries > main stream, and the Nenjiang Basin > Songhua Basin > Second Songhua Basin. The streamflow of Kumotun, Ayanqian, Fuyu, Changjiangtun were prone to drought in the early spring, while The streamflow of Jiangqiao, Taonan, Dalai, Harbin, Lanxi, Jiamusi were prone to drought in the late spring.
3. Analyzed the temporal variation of the sediment transport.
The maximum of sediment transport of Jiangqiao and Harbin was in 1998(respective 1.24×107t, 1.17×107t), and the maximum of sediment of Jiamusi was in 1994(3.97×107t), while the minimum of three hydrological stations was in 1979 (respective 0.27×106t、1.52×106t、2.11×106t). The smallest variation of sediment transport was Harbin, followed by Jiamusi, and the largest variation was Jiangqiao. Jiangqiao and Jiamusi showed an increasing trend in the sediment transport, but the increasing trend was not significant. The sediment transport of Harbin were significantly decreased, and there were two abrupt change points in 1978 and 1994. The anomaly cumulative curves of Harbin and Jiamusi in sediment transport had good consistency.
4. Precipitation, streamflow and sediment transport change and its response to human activities in Songhua Basin.
Taken harbin station for example, Precipitation, streamflow and sediment transport change and its response to human activities form 1955 to 2005 in Songhua Basin were analyzed. precipitation, streamflow and sediment transport had significant approximate periodicity and multi-time scale features. At the 7a scale, changes of precipitation, streamflow and sediment transport had the synchronization from 1950’s to 1960’s; in 1970’s, due to massive population move, as well as to address the irrational development of food problems led to three curve disorder; after 1980’s, the implementation of comprehensive measures made three curves re-converge. At 17a and 26a scales, because of water diversion project, the construction of reservoirs and other human activities, there was not always synchronization between the three curves. Wet and dry years and singular points were closely to the time scale.