Valuation of Lake and Marsh Wetlands Ecosystem Services in China

Wetlands are highly productive natural ecosystems, providing valuable goods and services. There is growing interest in transferring ecosystem service value from the existing wetlands studied to other wetlands ecosystems at a large geographic scale. The benefit transfer method uses the known values from wetlands to predict the value of other wetland sites. This methodology requires only limited time and resources. The present study calculated the value of the ecological services provided by lake and marsh wetlands in China in terms of biodiversity indices, water quality indices and economic indices. Basic data on wetlands were obtained through remote sensing images. The results show that: 1) The total ecosystem service value of the lake and marsh wetlands in 2008 was calculated to be 8.1841 × 1010 United States Dollars(USD), with the marsh and lake wetlands contributing 5.6329 × 1010 and 2.5512 × 1010 USD, respectively. Values of marsh ecosystem service were concentrated in Heilongjiang Province(2.5516 × 1010 USD), Qinghai Province(1.2014 × 1010 USD), and Inner Mongolia Autonomous Region(1.1884 × 1010 USD). The value of the lakes were concentrated in Tibet Autonomous Region(6.223 × 109 USD), Heilongjiang(5.810 × 109 USD), and Qinghai(5.500 × 109 USD). 2) Waste treatment and climate regulation services contributed to 26.29% and 24.74% respectively, of the total ecosystem service value of the marsh wetlands. Hydrological regulation and waste treatment contributed to 41.39% and 32.75%, respectively, of the total ecosystem service value of the lake wetlands. 3) The total ecological service value of the lake and marsh wetlands was 54.64% of the total service value of natural grassland ecosystems and 30.34% of the total service value of forests ecosystems in China.

Hydrochemical characteristics of salt marsh wetlands in western Songnen Plain

In western Songnen Plain of China, the saline-alkaline degree of water bodies is high in salt marsh wetlands. Generally, pH is above 8.0, and the hydrochemical types belong to HCO3 2?-Na+. Through analysis on the basic saline variables such as CO3 2?, HCO3 2?, Cl?, Ca2+, Mg2+, SO4 2?, Na+, and the derivative variables such as SAR, SDR, RSC, SSP, the relationships between different variables are found, and the discriminant equations are established to identify different saline-alkaline water bodies by using principal component analysis.

Analyses on Temporal and Spatial Variation Characteristics of Erosion and Deposition in the Front Edge of Salt Marsh Wetland

Taking Yancheng Nature Reserve Salt Marsh as the research object,the remote sensing images from 2005 to 2020 were interpreted by using remote sensing and geographic information system technology.In this paper,the temporal and spatial variation characteristics of erosion and deposition in the front edge of salt marsh wetland were analyzed.The influence of sea level rise on the annual change of salt marsh area was analyzed.The characteristics of flow and sediment movement in salt marsh and the causes of erosion and deposition in front of salt marsh were analyzed.The results showed that:(1)During 2005-2007,the sea level was relatively low,and Spartina alterniflora in salt marsh expanded to the sea.Since 2007,the front edge of salt marsh wetland has coexisted with erosion and deposition.From 2008 to 2010,the front edge of salt marsh wetland once again showed a trend of comprehensive deposition to the sea side.From 2010 to 2012,the erosion of salt marsh wetland was serious.From 2012 to 2020,the front edge of salt marsh wetland in the range of 9 km south of Xinyang estuary was eroded.(2)The correlation analysis was carried out between the area of salt marsh wetland and sea level rise.Spartina alterniflora is easily affected by sea level change,owing to it having a low ecological niche.With the rise of sea level,the area of salt marsh has been decreasing since 2013.(3)In the front sea area of salt marsh wetland,the maximum velocity of the ebb and flood can reach the threshold velocity during the spring tide.The sediment starts to move at water depth of 10 m under wave actions.Owing to wave stirs up sediment and current transports the sediment,resuspended sediment causes the erosion of marsh-edge scarps.

Response of Regeneration Diversity of Carex Lasiocarpa Community to Different Water Levels in Sanjiang Plain,China

The species diversity at the regeneration stage, inflenced by different water levels, is important for community composition in the later growing season.Regeneration diversity of Carex lasiocarpa community under different water levels was studied at two stages, recruitment and adult, in the Sanjiang Plain, Heilongjiang Province, China.The results showed that, at the two growing stages, important value of C.lasiocarpa population and species richness of the community decreased with the increasing water level, while the Simpson and Shannon-Wiener diversity indexes and Pielou evenness index increased.Under different water levels, community diversities were higher at the recruitment stage, while population important values of C.lasiocarpa were higher at the adult stage.Indexes in vegetation evaluation must be chosen prudentially for successful restoration and effective management of wetlands, and especially for wetland restoration, the optimal time should be selected according to the restoration objectives and costs.

Responses of Carex lasiocarpa Morphorlogical Characters to Water Regimes at Different Growth Stages

[Objective] The morphological characters of C.lasiocarpa were studied to find its morphological responses to different water regimes and growth stretagies through different water experiences.[Method] A seeding transplanting experiment with controlled water levels was set up,and the water level was changed at the middle of the season to compare water influence at the seeding stage and later growing period.C.lasiocarpa height,leaf length,leaf number,rhizome and adventitious roots length were measured at certain time througth the growing season.[Result] Results at the thriving season indicated that C.lasiocarpa height and leaf length in the experiment were similar to that in the field,but leaf number was higher under-5 cm water level and dry-wet alternate conditions than that in the field.At later growth period,height and leaf length under constant flooding(15cm) was significantly higher than that under other culture conditions,and also that of the field investigation;while the leaf number had a trend as-5 cm water level treatment>constant flooding>dry-wet alternate>field investigation.The height and leaf length were sensitive to seeding stage water effects,and leaf number sensitive to later influences.[Conclusion] Changes of water regimes in the growing season disturbed the growth of C.lasiocarpa,could accelerate or suspend its wilt,and modified the length of life history.

Remote Sensing Classification of Marsh Wetland with Different Resolution Images

Successful biological monitoring depends on judicious classification. An attempt has been made to provide an overview of important characteristics of marsh wetland. Classification was used to describe ecosystems and land cover patterns. Different spatial resolution images show different landscape characteristics. Several classification images were used to map and monitor wetland ecosystems of Honghe National Nature Reserve （HNNR） at a plant community scale. HNNR is a typical inland wetland and fresh water ecosystem in the North Temperate Zone. SPOT-5 10 m ×10 m, 20 m × 20 m, and 30 m×30 m images and Landsat -5 Thematic Mapper （TM） images were used to classify based on maximum likelihood classification （MLC） algorithms. In order to validate the precision of the classifications, this study used aerial photography classification maps as training samples because of their high accuracy. The accuracy of the derived classes was assessed with the discrete multivariate technique called KAPPA accuracy. The results indicate： （1） training samples are important to classification results. （2） Image classification accuracy is always affected by areal fraction and aggregation degree as well as by diversities and patch shape. （3） The core zone area is protected better than buffer zone and experimental zone wetland. The experimental zone degrades fast because of irrational development by humans.