The functions and services of wetland ecosystems to human society have been generally recognized. Currently, most evaluations of wetlands are a comprehensive evaluation of their ultimate value. It is rare to discuss for energy and matter lost and transferred. In this study, emergy theory was used to assess the ultimate and intermediate service values of the Liaohe estuarine wetland ecosystem. Results show that its ultimate service value was $28.2 million, and its intermediate service value was $35,614.03 million. The 1263 time difference between intermediate and ultimate value shows that much server value was dissipated in the form of energy. In the ultimate service value, the value of adjusting the atmosphere was $8.02 million, accounting for 28.45% of the total value, and flood diversion and storage value was $6.98 million, accounting for 24.75%. These results illustrate that the most important service value of the Liaohe estuarine wetland ecosystem is to adjust the atmosphere and divert and store floods. In intermediate service value, maintaining-biodiversity value was $34,182 million, accounting for 95.98% of total value, showing that the Liaohe estuarine wetland plays an important role in species resources and regional seed banks.

(1) Background: To reveal the intrinsic relationship between the tidal flat sediments in an estuary wetland and the runoff from the upstream river. This research was conducted in the tidal flats of the Liaohe estuary wetland. (2) Methods: The ¹³⁷Cs and ²¹⁰Pb dating technique was used to reconstruct the time correspondence between tidal flat sediments and runoff, and the periodic response was explored between the changes in the tidal flat sediments and runoff based on the spectrum analysis method. (3) Results: The average sedimentation rate in the tidal flat was 2.24 cm·year⁻¹ during the past 50 years. The amount of fine sediment particles deposited on the estuary tidal flat was directly related to the amount of sediments transported by the river and inversely proportional to the ability of rivers to transport fine matter. The high frequency reproduction cycle of 14–15 years in the flood season flow and 5–6 years in the annual sediment discharge of the Liaohe River correspond to the high and low frequency reproduction cycles of the median size of sediments in Liaohe estuarine wetland tidal flats. (4) Conclusions: The research clarified the hydrological constraints of the action law between Liaohe River runoff and the estuarine sediments. The periodic response between Liaohe River runoff and the sediment was established.

Phosphorus is an essential macronutrient that plays a crucial role in the regulation of the biological productivity and biogeochemical cycling of other biogenic elements. As a large tidal wetland dominated by reeds in Liaoning province, China, the Shuangtai estuary wetland is a unique ecosystem class. To better understand the spatial and temporal distributions of total phosphorus (TP) in the sediments of the Shuangtai estuary wetland during the period of reed growth, eight sampling sites were established within the wetland, approximately 11 to 24 km from Liaohe River. These sites were sampled once a month at multiple sediment depth intervals between April and October in 2018 and 2019, periods of time that corresponded with the reed growth period. An alkali fusion method was used to determine TP in the sediment samples. The results show that sediment TP content of wetland sediments ranged from 0.001 to 0.781 mg/kg, and decreases from southwest to northeast with the increase in sediment depth. The TP content reaches the maximum corresponding to the fastest growth stage of the reeds (June and July), while the minimum occurs in October (i.e., the maturity stage of reeds). The variation law of TP in cross-sectional sediment in the wetland is that the deeper the sediments are, the lower the content; its maximum content occurs in surface soil. The TP content of each site tends to be stable with increasing depth and has a regularly dynamic seasonal variation with the growth of reeds.