KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 新疆开都河流域水生植物生态化学计量学研究 | |
| Alternative Title | Study on the Ecological Stoichiometry of Aquatic Plants in Kaidu River Basin, Xinjiang |
| 彭庆文 | |
| Subtype | 硕士 |
| Thesis Advisor | 韩文轩 |
| 2020-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学硕士 |
| Keyword | 大型水生植物 干旱区淡水生态系统 生态化学计量 异速生长关系 中亚内流河/内陆河 Aquatic macrophytes Freshwater ecosystem in arid region Ecological stoichiometry Allometric relation Inland river/continental river of Central Asia |
| Abstract | 水生植物是水生态系统的重要组分， 对于维持和保护水生态系统的功能稳定性和生物多样性具有重要意义。 随着新疆地区经济的快速发展， 大量的氮（N） 、磷（P） 等营养元素进入当地的河流和湖泊中， 并进而影响水生植物等生物的生态化学计量特征。 开都河是新疆一条重要的内流河， 沿河分布着不同的土地利用类型、 受到各种人类活动的影响； 开都河生态系统有何化学计量特征？ 其分布格局与不同河段的人类活动方式以及局地气候是否和有何关联？ 至今尚未有系统研究。 为此， 本研究通过实地采样和运用统计分析方法， 对开都河流域水生态系统（水生植物、 水体和沉积物） 的化学计量特征开展研究， 并探讨了其与人类活动（如土地利用方式） 和局地气候的可能关联性。 主要研究结果如下：（1） 开都河水体总氮（TN） 和总磷（TP） 含量分别为 0.75 mg·L-1和 0.036mg·L-1， TN:TP 为 22.8。 沉积物中 N 和 P 含量分别为 2.50 mg·g-1和 0.71 mg·g-1，N:P 的平均值为 3.25。 与十几年前的有关监测结果相比， 开都河水体 TN、 TP 含量明显减少， 这可能与近年来当地政府实施更严格的环保政策以及推动农牧业绿色生产方式密切相关。（2） 开都河流域水生植物叶碳（C） 、 N、 P 含量分别为 406.6、 24.9 和 2.49mg·g-1， C:N 和 C:P 分别为 19.1 和 236.7， N:P 为 12.6。 C 与 N、 N 与 P 之间存在显著正相关关系； 开都河流域水生植物 N~Pα异速生长关系的幂指数α为 0.66， 与全球陆生植物相近， 表明开都河流域水生植物与全球陆生植物具有一致的 N、 P异速分配模式。（3） 沉水植物叶 C 含量（381.3 mg·g-1） 显著低于挺水植物（416.3 mg·g-1）和浮叶植物（424.3 mg·g-1） ， 沉水植物叶 N、 P 含量最高（分别为 26.0 和 2.90mg·g-1） 。 不同生活型水生植物的叶 C:N、 C:P 均不存在显著差异， 但浮叶植物叶 N:P（19.2） 显著高于挺水植物（12.9） 和沉水植物（10.3） ， 表明浮叶植物可能比其他两类植物更易受 P 限制。（4） 水生植物、 沉积物和水体 N 含量的空间分布格局一致， 表现为上游水生植物叶、 沉积物和水体 N 含量均高于下游； 草地区河段水生植物叶、 沉积物和水体 N 含量高于耕地区和未利用荒地区。 上下游以及不同土地利用类型差异对水体和沉积物 P 含量的影响不明显。（5） 开都河水生植物叶 C 含量不随纬度、 海拔、 年均温（MAT） 和年均降水（MAP） 变化。 叶 N 和叶 P 随纬度和海拔的增加而增加， N:P 随纬度的增加而增加； 叶 N 和叶 P 随 MAT 的降低和 MAP 的增加而显著增加。 叶 N:P 与海拔之间不存在显著的线性关系， 随 MAT 的降低和 MAP 的增多而降低。（6） 叶 C 含量与水体和沉积物各指标之间均不存在显著相关性； 叶 N 和叶P 含量与水体 pH 呈显著负相关关系， 叶 P 含量与水体 N 含量之间存在显著正相关关系； 叶 N 和叶 P 含量随沉积物 C、 N 含量的增加而显著增加。（7） 通过运用一般线性模型， 对开都河流域水生植物生态化学计量特征主要驱动力进行研究发现： 叶 C 含量仅受生活型影响， 解释度为 18.11%； 降水是对水生植物叶 N、 P 解释度最高的环境因子， 解释度分别为 8.02%和 6.28%。本研究首次系统地报道了开都河水生态系统（水生植物、 水体和沉积物） 中C、 N、 P 的化学计量特征， 并探讨了其与人类活动的可能关联。 本研究结果有助于促进人们对高山或干旱区河流生态系统的 N、 P 循环特征及其对全球环境变化响应的理解， 也为新疆地区水生生态系统生物地球化学循环的研究提供了基础数据和参考案例。 |
| Other Abstract | Aquatic plants are one of the important components of water ecosystem, which isof great significance for maintaining and protecting the stability and biodiversity ofwater ecosystem. With the rapid development of economy in Xinjiang, the nitrogen(N) and phosphorus (P) input to the local rivers and lakes has increased significantlyin recent decades. However, it is unclear how these changes in nutrient stoichiometryof water ecosystems should affect the ecological stoichiometric characteristics ofaquatic plants in Kaidu River, which is one of the major inland rivers in Xinjiang?Therefore, the stoichiometric characteristics of aquatic ecosystems (aquatic plants,water bodies and sediments) and their possible relations with human activities (suchas land-use patterns) and the local climates along Kaidu River were studied throughfield sampling and statistic analysis. The main results are as follows:(1) The total contents of N (TN) and P (TP) in the water of Kaidu River were0.75 mg·L-1 and 0.036 mg·L-1, respectively, and the TN:TP ratio was 22.8. The TNand TP in the sediments were 2.50 mg·g-1 and 0.71 mg·g-1, respectively, and the N:Pwas 3.25. Compared with the monitoring data over ten years ago, the TN and TPcontents in the water of Kaidu River were significantly reduced, which may reflectthe effects of the stricter enforcement of environmental protection laws andregulations by the local government, as well as the conversion to a green productionmode for the local agriculture and animal husbandry.(2) The leaf C, N and P contents of aquatic plants in the Kaidu River wererespectively 406.6, 24.9 and 2.49 mg·g-1, and the C:N and C:P were 19.1 and 236.7,respectively. The N:P was 12.6. There was a significant positive correlation betweenC and N and between N and P. The allometric relation between N and P of the aquaticplants in Kaidu River was N ~ P0.66, which is similar to that of global terrestrial plants,suggesting that both these aquatic plants and the general terrestrial plants shared asimilar allometric pattern between N and P.(3) The leaf C content of submerged plants (381.3 mg·g-1) was significantlylower than that of emergent plants (416.3 mg·g-1) and floating-leaved plants (424.3mg·g-1), and both leaf N (26.0 mg·g-1) and P content (2.90 mg·g-1) of submergedplants were the highest among all the life forms. There was no significant differencein leaf C:N and leaf C:P among different life-forms, but the leaf N:P (19.2) offloating-leaved plants was significantly higher than that of emergent plants (12.9) andsubmerged plants (10.3).(4) The nitrogen (N) contents of macrophytes, sediments and waters showed thesimilar spatial distribution pattern. Specifically, the N contents of macrophytes,sediments and waters were higher in the upstream relative to downstream, and in theriver reaches of grassland regions relative to those of farming areas and abandonedwastelands. In contrast, water and sediment P contents did not show significantdifferences between upstream and downstream, and among different land use types.(5) Leaf C content of the macrophytes in Kaidu River insignificantly changedwith latitude, altitude, MAT and MAP. Leaf N and P contents increased with theincreasing latitude, altitude and MAP, while decreased with the increasing MAT. LeafN:P increased with the increasing latitude and MAT, decreased with the increasingMAP, but exhibited insignificant relationship with altitude.(6) Leaf C content had insignificant correlations with all the variables of waterand sediment. Leaf N and P contents decreased with the increasing water pH, andincreased with the increasing sediment C and N contents. In addition, leaf P contentdisplayed a significantly positive relationship with water N content.(7) Based on the general linear model analysis, we explored the main drivingforces of the variability in the ecological stoichiometric characteristics ofmacrophytes in the Kaidu River basin. Our results showed that leaf C content wasmainly explained by life form, which contributed 18.11% of the total variance in leafC. In contrast, leaf N and P content were mainly explained by precipitation, whichaccount for 8.02% and 6.28% of the total variances in leaf N and P, respectively.In conclusion, this study documented for the first time the stoichiometric characteristics of the aquatic ecosystem (macrophytes, water, and sediments) of KaiduRiver, and explored their possible links with land-use types and anthropogenicimpacts. These findings can help advance our understanding about the characteristicsof N and P cycles and their responses to global changes in the river ecosystems in thealpine or arid regions, and also provide the fundamental data and reference case forthe studies of biogeochemical cycles in the aquatic ecosystems in the Xinjiang region. |
| Subject Area | 生态学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15442 |
| Collection | 中国科学院新疆生态与地理研究所 研究系统 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 彭庆文. 新疆开都河流域水生植物生态化学计量学研究[D]. 北京. 中国科学院大学,2020. |
| Files in This Item: | There are no files associated with this item. | |||||
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Edit Comment