%0 Journal Article %T 中国特有植物沙地云杉的濒危机制 %T Endangered Mechanism of Picea Mongolica: An Endemic and Evergreen Tree only Found in Desert Areas of China %A 刘有军 %A 刘世增 %A 康才周 %A 满多清 %A LIU,Youjun %A LIU,Shizeng %A KANG,Caizhou %A MAN,Duoqing %J 水土保持通报 %J 水土保持通报英文版 %@ 1000-288X %V 38 %N 3 %D 2018 %P 60-65,73 %K 沙地云杉;种子生活力;种子萌发;幼苗生长;土壤种子库;濒危原因 %K Picea mongolica;seed viability;seed germination;seedling growth,soil seed bank,endangered reasons %X [目的]探索中国特有植物沙地云杉濒危的原因,为制定沙地云杉天然林保护措施提供理论依据。[方法]通过栖息地不同储藏时间种子质量测定,研究种子萌发对温度、光照和沙埋的响应以及种子萌发和幼苗生长对盐分胁迫耐受性。[结果]①种子成熟时生活力仅为79%,其中12%的种子遭受了冻害,其余67%种子不同程度遭受了虫害和病害,且种子生活力随着栖息地埋藏每年以9.5%速度下降。②种子在大于10℃温度范围内萌发率均大于40%,且在黑暗/光照交替下萌发速度大于其他光照条件,而沙地云杉出苗最适沙埋深度为0.5 cm,满足种子萌发温度和光照条件,这增加了在栖息地大量种子萌发后死亡的危险。③种子萌发和幼苗生长随着盐分胁迫浓度增加显著降低,当盐分浓度0~100 mmol/L时,种子初始萌发率(RIG)由69%降到49%,恢复萌发率(RGR)由0增加到6%,初始幼苗长度(LIS)由7.12 cm降到1.16 cm,恢复幼苗长度(LRS)仅由0 cm增加到0.03 cm,当盐分浓度大于100 mmol/L时,种子萌发和幼苗生长受到严重抑制(RIG<49%,LIS<1.16 cm)且恢复能力极差(RGR<10%,LRG<1 cm),但土壤含盐量大于100 mmol/L的沙地在沙地云杉的栖息地很容易找到。④出苗率随着沙埋深度增加显著降低。在0.5 cm时出苗率69%,在2 cm时降为8.50%,在沙地云杉栖息地沙埋厚度很容易超过2 cm,因此,出苗率小于8.5%。而小于8.5%幼苗出土后还要反复遭受虫害、病害、冻害、水盐胁迫和种间竞争等影响。[结论]栖息地自然土壤种子库中沙地云杉种子病虫害严重,生活力低和幼苗存活率低以及环境恶劣是导致沙地云杉濒危主要原因。 %X [Objective] To explore the endangered reasons of Picea mongolica at the seed ecology level in order to provide theoretical references for making the conserve measures of P. mongolica natural forest.[Methods] Seed viability was tested with different habitat storage periods. The responses of seed germination to temperatures and lights were investigated. The tolerance of P. mongolica seed to salinity during seed germination and seedling growth and the responses of seedling emergence to sand burying were studies.[Results] ① The viability of matured P. mongolica seeds was 79%, of which, about 12% seeds suffered from freeze injury and the remaining 67% suffered from the pest nibble and disease harm. The buried seed viability was reduced at a speed of 9.5% every year. ② Germination of P. mongolica seeds was very easy and the germination percentage was more than 40% when the temperature was more than 10℃. The seed germination rate at a dark-light alternation condition was higher than other light conditions, and the optimal sand burial depth for P. mongolica seedling emergence was 0.5 cm as it satisfied the light and temperature requirements of seed germination. The germination characteristics increased the morality as a lot of seeds germinated in desert habitat environments. ③ Seed germination and seedling growth were significant decreased with the increase of NaCl concentration. When NaCl concentration was around 0~100 mmol/L, the germination rate (RIG) was decreased from 69% to 49%, recovery germination rate (RGR) was increased from 0 to 6%, and the initial seedling length (LIS) was reduced from 7.12 to 1.16 cm. The recovery seedling length (LRS) was increased from 0 to 0.03 cm when the concentration of NaCl was more than 100 mmol/L, the seed germination and seedling growth were completely inhibited(IGR<49%,ISL<1.16 cm) and the ability to recover was poor (RGR<10%, LRG<1 cm). Unfortunately, soil salinity contents over 100 mmol/L were widely distributed in the natural habitat of P. mongolica. ④ Seedling emergence was significantly decreased with the increase of sand burial depths. The emergence rate reached 69% with the 0.5 cm sand burial depths and reduced to 8.5% with the 2.0 cm sand burial depths. The habitat of P. mongolica with sand burial depths over 2.0 cm was widely distributed, thus the seedling emergence was less than 8.5%. The P. mongolica seedling was continuously suffered from the pest nibble, disease harm, salinity and moisture stress, freeze injury and interspecific competition.[Conclusion] The main endangered causes of P. mongolica were the serious diseases and pests, low seed viability in habitat soil seed banks, the low survival rate of seedlings and badly environments in habitats. %R 10.13961/j.cnki.stbctb.2018.03.010 %U http://stbctb.alljournal.com.cn/stbctb/home %1 JIS Version 3.0.0