三江平原沼泽湿地的蓄水与调洪功能

Water Storage and Flood Regulation Functions of Marsh Wetland in the Sanjiang Plain

以三江平原挠力河1956—2000年宝清站与菜咀子站实测的洪峰流量为例，分析沼泽湿地的蓄水与调洪功能。在该河45a的实测洪峰流量中，有26a是下游菜咀子站的洪峰流量小于上游宝清站，表明有大量洪水在其间的河漫滩沼泽（面积28．82×10^4hm^2）之中漫散与蓄存。沼泽的巨大蓄水能力，与其土壤容重小、孔隙度大、持水能力强有关。三江平原沼泽土壤草根层与泥炭层的容重为0．10-0．28Mg／m^3，总孔隙度大于70％，饱和持水量可达4000—9700g／kg，估算全区沼泽土壤的蓄水总量可达46．97×10^8m^3。由于沼泽均分布在地势低洼的负地貌部位，地表平均积水30cm，则全区沼泽地表积水的储水量还可达17．15×10^8m^3。根据沼泽湿地的蓄水、调洪功能与生物多样性价值，提出严禁开垦与破坏现有的河漫滩沼泽，实施湿地保护的生态工程。

The water storage and flood control functions of marsh wetland were analyzed, based on the data of flood peak discharge monitored at Baoqing station and Caizuizi station in the Naoli river basin of the Sanjiang Plain from 1956 to 2000. The flood peak discharges monitored at Caizuizi station were less than those monitored at Baoqing station for 26 years during 45 years. It showed that there was a large amount of flood water spread and reserved in the marshes（ their area is 28.82 × 10^4 hm^2 ）. The tremendous water storage capability of marshes was related to the bulk density, porosity and water holding capacity. The marsh soil bulk densities were 0.10 Mg/m^3 to 0.28 Mg/m^3, the total porosity was bigger than 75%, the water - holding capacities were 4 000 g/kg to 9 700 g/kg of grass root layer and peat layer in the Sanjiang Plain. It was estimated that water storage amount of marsh soils was 46.97 ×10^8 m^3. Since marshes distribute at low land, average water level is 30 cm, then the water storage amount is 17.15 ×10s m^3. According to water storage amount, flood regulation functions and biodiversity value of marshes in the Sanjiang Plain, the suggestions of forbidding reclamation en. Ecological engineering for wetlands protection should be carried on. and flood plain destroy were giv en. Ecological engineering for wetlands protection should be carried on.