三江平原沼泽湿地开垦后的热量平衡变化

三江平原沼泽湿地分布广泛且集中，沼泽湿地局地冷湿效应显著，但随着沼泽湿地开垦面积的增加，导致区域热平衡发生一系列的变化，最终会影响整个区域的生态环境。1997－1999年间、以三江平原沼泽湿地生态试验站为研究基地，从热平衡的角度出发，采用小气候自动观测仪器采集数据，研究区域沼泽湿地的热平衡状况。主要观测要素有：总辐射、净辐射、反射率等，并与开垦后的农田进行对比，探讨沼泽湿地生态系统演化的热平衡结构的变化规律。研究结果表明：沼泽湿地开垦后，地表反射率减少了16％左右，地表接受的太阳辐射增加了8％－10％，地表显热交换活跃，虽然这大大改善了土壤的热状况，有利于农田作物的生长，但明显改变了沼泽湿地原有的冷湿效应，减弱沼泽湿地特有的环境效应，随着湿地开垦面积的增加，必然导致区域生态平衡的变化。

Heat Balance Change of the Reclaimed Mire-wetlands Ecosystem in the Sanjiang Plain,NE China

In the Sanjiang Plain, ME China, mires and wetlands distribute widely and have an obvious effect on the surrounding air by reducing temperature and raising humidity. With the increasing mire cultivation area, the regional heat balance has changed. From 1997 to 1999, the authors collected data by microclimate automatic observational instruments to study the heat balance state in this area. The major factors of heat balance are as follows: global radiation, net radiation, albedo ratio etc. By comparing it with farmland on heat balance, the authors obtained the change law of heat balance of controlling the evolution of wetland ecosystem. The result shows that after reclamation, the albedo ratio of mire reduces by 16%. It receives 8% - 10% more solarradiation and heat change becomes more active. It can improve heat condition of the earth, and it contributes to crop production. But it can weaken the original effect on the surrounding air of mire-wetland. With the increasing cultivation area, it has resulted in the change in the regional ecological balance.