<正>利用支付卡式的条件价值评估（CVM）技术，通过发放调查问卷及访谈的形式，对公众改善长江水质的支付意愿进行了深入的研究。结果表明：（1）南京市居民对长江水质恢复的户均年支付意愿为100.66元，76.5%的受访者支付意愿大干0，8.4%的受访问者虽有支付意愿但限于低经济收入原因其支付意愿为0，15.1%的受访者拒绝支付；（2）影响居民支付意愿的主要因素包括家庭收入、环境意识及文化程度；（3）南京市居民偏爱的支付方式依次为捐款、交税、存取基金方式及提高水价。根据调查结果，增加收入、提高环境意识、引入“谁受益、谁支付”观点、提高政府资金管理与使用的合理性是提高居民支付意愿的有效途径。

Fingerprints of 53 Taxodium mucronatum Ten. clones were constructed with RAPD (Random amplified polymorphic DNA) markers, al primers screened could result in 241 loci, of which 118 (48.96o/oo) loci were polymorphic. The genetic distance among clones ranged from 0. 271 to 0. 537. These results indicated that the genetic diversity among clones was relatively high. Cluster analysis based on the genetic distance showed that RAPD fingerprints could reveal the genetic relationship of the clones. 53 clones studied were successfully discriminated using the constructed RAPD fingerprints which could be of great importance for identification of clones.