应用VSD动态酸化模型确定区域酸沉降控制目标研究

为了控制区域酸沉降污染,需要制定科学的区域大气酸沉降控制目标.本研究建立了应用VSD动态模型的多点位模拟和累积频率分布曲线统计方法,通过模拟各酸沉降情景下某一目标年区域内土壤理化特性的变化确定其酸沉降控制目标.将此方法应用于广州-东莞-惠州地区,在现场测量区域内25点位土壤特征的基础上,应用VSD模型模拟各点位土壤特征对酸沉降的响应,再将模拟结果绘制成累积频率分布曲线,据此确定该区域酸沉降控制目标.结果表明,单独控制S沉降时,若使得该区域生态保护率达到80%,则短期和长期S沉降的控制目标分别为7.68~12g/(m2×a)和10.24~16g/(m2×a);若生态保护率为95%,短期和长期S沉降控制目标分别为5.12~8g/(m2×a)和7.68~12g/(m2×a).同时控制S和BC沉降时,若生态保护率为80%,当BC沉降为6.4~12.8g/(m2×a)时,短期和长期S的控制目标分别为2.56~4g/(m2×a)和5.12~8g/(m2×a);当BC沉降为4.8~9.6g/(m2×a)时,S的控制目标为2.56~4g/(m2×a).若生态保护率为95%,当BC沉降为6.4~12.8g/(m2×a)时,短期和长期S的控制目标分别为0.64~1g/(m2×a)和5.12~8g/(m2×a);当BC沉降为4.8~9.6g/(m2×a)时,短期和长期S的控制目标分别为0.64~1g/(m2×a)和2.56~4g/(m2×a);当BC沉降量降至2~4g/(m2×a),则80%和95%生态保护率下的S控制目标均为0.64~1g/(m2×a).

Determining regional control targets of acid deposition using VSD model

Setting scientific acid deposition control targets was necessary to control regional acid deposition pollution. A method to set such control targets by analyzing soil acidity at selected sites under different acid deposition scenarios in the target years, combining the VSD model and cumulative frequency distribution analysis, was proposed in this study. This method was applied to the Guangzhou-Dongguan-Huizhou region. The soil acidity in 25 sites was measured and simulated by using VSD model under different acid deposition scenario, and the results were described by using cumulative frequency distribution curve. The S deposition target under different scenarios was given in the results. If S deposition was controlled solely, the short-term and long-term S deposition control targets should be 7.68~12g/(m2×a) and 10.24~16g/(m2×a), respectively, to guarantee that 80% of the ecosystem was protected, and the short-term and long-term S deposition control targets should be 5.12~8g/(m2×a) and 7.68~12g/(m2×a) respectively, to guarantee that 95% of the ecosystem was protected. If S and BC deposition were controlled simultaneously, when BC deposition was 6.4~12.8g/(m2×a), the short-term and long-term S deposition control targets should be 2.56~4g/(m2×a) and 5.12~8g/(m2×a), respectively, when BC deposition was 4.8~9.6g/(m2×a), the S deposition control target should be 2.56~4g/(m2×a), to guarantee that 80% of the ecosystem was protected; when BC deposition was 6.4~12.8g/(m2×a), the short-term and long-term S deposition control targets should be 0.64~1g/(m2×a) and 5.12~8g/(m2×a), when BC deposition was 4.8~9.6g/(m2×a), the short-term and long-term S deposition control targets should be 0.64~1g/(m2×a) and 2.56~4g/(m2×a), to guarantee that 95% of the ecosystem was protected. When BC deposition was reduced to 2~4g/(m2×a), S deposition should be controlled to 0.64~1g/(m2×a) to make sure that 80% and 95% of ecosystem was protected. Restoration measures should be taken at the same time.