论洞庭湖区泥沙淤积灾害与泥沙灾害链

On Silt Deposit and Disastrous Chains Originated from Silt Deposit inDongting Lake Area

洞庭湖多年平均泥沙淤积量达13×107t,长期的泥沙淤积,塑造了特殊的湖泊生态环境.在这一特定环境条件和人类活动扰动下,其结果是:助长泥沙淤积,逐渐扰乱湖泊生态系统的平衡状况,形成了次生和衍生灾害的孕灾环境.孕灾环境的异变,则放大了泥沙淤积的致灾能量,进而触发了多条泥沙灾害链的形成与群发,诸条泥沙灾害链的成链和发展过程均起源于长期的泥沙淤积,都属于渐近累积式灾害,且在时空上,成因上具有明显的关联性.

The overyear average amount of silt deposit in Dongting Lake is as high as 13 × 107 t, Long-term silt deposit contribute to special ecological environment. The special circumstance and destructive activities of people accelerated the speed of silt deposit broke the balance of ecological system, and formed secondary disastrous environment. Subsquently, the abnormal change of environment amplified the impact of silt deposit, result in the format and cocurrence of disasfrous chains in the final analysis, the gradual formation process of disastrous chains all originated from the long-term silt deposit.