【作者】 郑志华；

【导师】 张志翔；

【作者基本信息】 北京林业大学 ， 野生动植物保护与利用， 2008， 硕士

【摘要】 由于各种原因,白鹤食源植物的生境却在逐年退化。通过实地考察和对白鹤排泄物等的分析,发现白鹤主要以扁杆藨草等植物的地下球茎及少量鱼虾类为食,而作为其主要食源植物的扁杆藨草(Scirpus planiculmis)的生境在近年也随之遭到了严重破坏,并使得白鹤在该地区的停歇地和食物有逐年递减的趋势,威胁到白鹤在此地的生存。水资源的枯竭是莫莫格湿地退化最关键的因素。扁杆藨草是典型的湿生植物,其生长与水,尤其是土壤水分含量密切相关。湿地土壤含水量与扁杆藨草生长的定量分析是扁杆藨草在莫莫格湿地恢复过程中的关键所在,也是合理利用和保护湿地生物多样性,保证湿地结构与功能完整性,实现区域可持续发展的重要手段。在分析其与土壤生境关系的同时,结合扁杆藨草自身繁殖特性,建立扁杆藨草在莫莫格湿地的恢复技术。由于扁杆藨草是典型的湿生植物,对水分要求比较严格,沿着土壤水分梯度,并根据扁杆藨草生长的高度和盖度,将扁杆藨草的生长等级分成四个等级,并对四个等级上的土壤水分含量和土壤盐分含量进行研究,找到适宜扁杆生长的土壤含水量和土壤含盐量的最佳值及临界值,为扁杆藨草在莫莫格湿地的恢复提供理论依据。同时,对扁杆藨草的繁殖机理进行试验研究,发现扁杆藨草主要通过地下球茎的根蘖能力进行营养繁殖。通过以上研究,得出以下主要结论:扁杆藨草主要通过地下球茎进行营养繁殖,越冬球茎于每年4月中旬开始萌动形成地上植株,随着地上茎叶的不断生长,越冬球茎开始形成新的根状茎,新根状茎生长不久顶端膨大形成新的球茎,到5月下旬新根状茎、新球茎及再生根状茎、再生球茎的数量达到高峰。从球茎分布规律看,主要集中在0~10cm的土层范围内,因此在做土壤水分和盐分等研究时,主要集中在0~10cm土层左右即可。莫莫格湿地近年来遭受干旱侵袭,水资源有限,利用有限的水资源最大面积的恢复扁杆藨草的生长,是莫莫格湿地恢复的关键技术。在扁杆藨草与土壤生境关系中,随着土壤水分含量的逐渐降低,土壤中的盐分含量逐渐增加,扁杆藨草生长呈衰弱趋势,逐步被碱蓬等旱生盐碱植物所代替,直至扁杆藨草消失完全被碱蓬等代替,土壤水分和盐分含量也达到扁杆藨草生长的极限值。扁杆藨草生长与土壤水分含量和土壤盐分含量的关系:当扁杆藨草处于最佳生长状态,其临界土壤水分含量和土壤盐分含量分别为25%~27%,0.125%~0.375%;当土壤水分含量为21%~25%,土壤含盐量为0.375%~1%时,碱蓬等耐盐碱植物出现,但扁杆藨草仍能正常生长;当土壤水分含量降至20%~21%,土壤含盐量提高到1%~2.75%时,碱蓬等耐盐碱植物大量出现,取代扁杆藨草而成为群落的主导,扁杆藨草呈零星分布状态,丧失自我恢复的功能;而当土壤水分含量降至14%~17%,土壤含盐量增至1.75%~3.125%时,扁杆藨草在植物群落中被碱蓬等耐盐碱植物代替而完全消失。更多还原

【Abstract】 For identify possible causes,the habitat of the plant which Grus leucogeranus depended on has been destroyed yearly.It was found out that the Grus leucogeranus live by the underground corm of the Scirpus planiculmis and some fingerling.As one of the important food of the Grus leucogeranus,the habitat of Scirpus planiculmis has been destroyed seriously . The food and the habitat decreased yearly. The living environment of the Grus leucogeranus are being destroyed.The most key factor of the degradation in Momoge wetland is the dry up of the water resource. Scirpus planiculmi is emblematical hygrophytes,the growth of it closely related to the water resource especially the soil water content. Quantitative analysis between the soil water content of the wetland and the growth of Scirpus planiculmi is the key point during the rejuvenation in Momoge wetland and also is the important methed to protect and exploit wetland biodiversity reasonably, to guarantee the completeness of The structure and functions of wetland and to to realize the region sustainable development.In order to set up the restoration system of the Scirpus planiculmi in Momoge wetland,the relation between the growth of Scirpus planiculmi and soil habit and the propagation characteristic of Scirpus planiculmi has been studied.As the emblematical hygrophytes,the growth of Scirpus planiculmi needs water strictly.The growth of the Scirpus planiculmi is divided into four levels by the height and coverage of Scirpus planiculmi along the soil gradation of moisture. In order to provide the theoretical base on the Scirpus planiculmi restoration technique in Momoge wetland and find out the best value and critical value on soil water conent and soil salinity content which suitable for Scirpus planiculmi,the soil water conent and soil salinity content has been studied .At the same time,the propagation mechanism of Scirpus planiculmi has been studied and shows that Scirpus planiculmi propagated by the underground corm.The main results are described as follows:1.Scirpus planiculmi propagated by the underground corm,and the overwintering corm begin to bourgeon in middle third in April and form the overground part.With the uninterrupted growing of the overground Stem and leaf, the overwintering corm become to form new rhizome and the topmost of the new rhizome form new corm.When is comes to the last third of the month in May,the number of the new rhizome、new corm and reborn rhizome、new reborn corm reach to the peak.2.From the distribution rule of the corm,it distribute in the soil in 0~10cm.When the soil water content and soil salinity content are studied ,the depth of the soil focus on the 0~10cm. 3.For the past few years, for the drought in Momoge wetland,the water resource is limited.How to restore the growth of the Scirpus planiculmi maximality with limited water resource is the key technology in Momoge wetland.4.In the relation between the Scirpus planiculmi and soil habit ,for the soil water content bring down gradually,the soil salinity content increase gradually and the growth of Scirpus planiculmi comes to weak up until disappeared completely and instead by Suaeda glauca and other salt tolerant plants.The soil water content and soil salinity content also reach to the ultimate value at last.5.The relation between the growthof Scirpus planiculmi and the soil water content and soil salinity content:when growth of the Scirpus planiculmi is in its best status,the critical soil water content and soil salinity content are 25%~27% and 0.125%~0.375%;when the soil water content break down to 21%~25% and the soil salinity content reached 0.375%~1%,the Suaeda glauca and othe salt tolerant plants appeared,but Scirpus planiculmi is still in its normal growth ;when the soil water content break down to 20%~21% and the soil salinity content reanched 1%~2.75%, Suaeda glauca appeared abundant and become the most important plant in the plant community instead of the Scirpus planiculml,and the Scirpus planiculml distributed Sporadically and forfeited the function for self-healing.When the soil water content reduced to 14%~17% and the soil sali nity went up to 1.75%~3.125%,the Scirpus planiculml disappeared completely.更多还原