不同演替阶段生物结皮中藻类与藓类植物优势种群种间关系研究

Desertification is one of important ecological environment problems in the world, and biological soil crusts (BSCs) provide a well biological avenue for controlling desertification. Algae and moss are two important compositive parts of BSCs and they are together concerned with successional processes of BSCs. Algal crust and moss crust are two important successional stages during the development process of biotic crusts. During successional processes of BSCs, we find that distribution pattern between algae and moss takes on distinct variation for moss increase and algae decrease, and infer that it may be a reflection of interspecific relationships between algae and moss. However, research on interspecific relationships of algae and moss within BSCs are lack and not profound till now. How are the interspecific relationships between algae and moss of BSCs on earth? It provides a well scientific issue for us and need be resolved. In this study, we will explore interspecific relationships between algae and moss in BSCs by means of quantity analysis, experimental populations and also by using field survey, laboratory determination and experimental simulation, and interspecific association, interspecific correlation and interspecific co-dynamics as well as interspecific allelopathy will be investigated between dominant populations of algae and moss at different successional stages of BSCs. Research results will clarify reciprocity and affiliation between algae and moss during successional processes of bitotic crusts, and further expose inherent rules from distribution patterns, population evolution and community dynamics between algae and moss in BSCs. Simultaneously, the project will be an valuable reference for basic theory researches of biotic crusts, and will afford some directions for reestablishment and restoration of BSCs.

荒漠化是世界性的生态环境问题，生物结皮为荒漠化治理提供了良好的生物学手段。藻类和藓类植物是生物结皮中两个重要组成部分，它们共同参与生物结皮的发育演替过程。藻类结皮和藓类结皮是生物结皮中不同的演替阶段，在演替过程中藻类与藓类植物分布格局呈现藓增、藻减的变化，这可能是结皮藻类和藓类植物种间关系的反映。但目前有关二者种间关系的研究十分匮乏。在不同演替阶段，结皮藻类与藓类植物之间呈现怎样的种间关系？这为我们提出需要研究的问题。本项目拟采用数量分析法和实验种群研究法，结合野外调查、室内分析与实验模拟，对结皮藻类与藓类植物优势种群种间关系展开深入研究，探讨二者种间联结性与相关性、种间相互动态和种间他感作用，旨在阐明结皮演替进程中藻类与藓类植物之间的相互作用和相互联系，揭示二者之间的分布格局、种群进化和群落动态等内在规律。本项目将为生物结皮的基础理论研究提供参考，并为生物结皮的人工恢复与利用提供指导

藻类和藓类植物是生物结皮中两个重要组成部分，它们共同参与生物结皮的发育演替过程。但目前有关结皮藻类和藓类植物种间关系的研究十分匮乏。.本项目以我国典型荒漠区不同演替阶段的生物结皮为材料，采用数量生态学，结合野外调查、室内分析等方法，对结皮藻类与藓类植物优势种群种间关系展开研究。采集了鄂尔多斯库布齐沙漠和沙坡头腾格里沙漠结皮藻类和苔藓植物，对结皮藻类和藓类植物优势种进行了分离、培养和鉴定，确定了结皮藻类与藓类植物优势种群。结果表明，库布齐沙漠结皮藻类24种，包括蓝藻门15种，绿藻门6种和硅藻门3种。腾格里沙漠生物结皮藻类22种，其中蓝藻12种，占54.55%；绿藻5种，占22.73%；硅藻5种，占22. 73%。沙坡头地区生物结皮中，真藓、土生对齿藓、双齿赤藓和刺叶赤藓等为优势种；鄂尔多斯地区生物结皮真藓、土生对齿藓等为优势种。沙坡头地区和鄂尔多斯地区生物结皮中的藓类植物主要包括丛藓科、真藓科和葫芦藓科等3 科藓类植物，共7属15种。.通过运用数量分析法，对藻类与藓类植物优势种群种间关联性和相关性进行了分析，联结度指数Jaccard指数（JI）、Dice指数(DI)、Ochai指数(OI) 以及Pearson相关系数（r）被测定。同时，制备了结皮藻类胞外代谢物、胞外多糖和苔藓植物浸提液，测定了结皮藻类胞外分泌物对苔藓植物孢子萌发、原丝体发育的影响，以及苔藓植物浸提液对结皮藻类生物量、光合活性的影响。表明结皮藻类胞外代谢物和EPS能够促进结皮藓类孢子萌发和原丝体发育；结皮藓类植物浸提液对结皮藻类的生理活性呈明显的浓度效应，表现为“低促高抑”现象。.本项目研究结果揭示了不同演替阶段生物结皮中藻类与藓类植物优势种群的种间关系变化特征及相互作用关系，初步阐明了藻类与藓类植物的种间竞争与共存机理。为进一步揭示化感作用在生物结皮中藻类与藓类植物的种群消长与群落演替中的生态学机制提供了实验基础和科学依据。本项目也为生物结皮的基础理论研究提供参考，并为生物结皮的人工恢复、重建与利用提供指导。