See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/309858554 Macroinvertebrate assemblages in relation to environments in the Dongting Lake, with implications for ecological management of river- connected lakes Article in Environmental Progress & Sustainable Energy · October 2016 DOI: 10.1002/ep.12510 CITATIONS READS 0 70 6 authors, including: Baozhu Pan Haijun Wang Changjiang River Scientific Research Institute Chinese Academy of Sciences 45 PUBLICATIONS 359 CITATIONS 35 PUBLICATIONS 380 CITATIONS SEE PROFILE SEE PROFILE Zhiwei Li Changsha University of Science & Technology 29 PUBLICATIONS 101 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: wind induced flow velocities and their role in destratification, nutrients resuspension and hypoxia reduction View project All content following this page was uploaded by Zhiwei Li on 12 October 2017. The user has requested enhancement of the downloaded file. Macroinvertebrate Assemblages in Relation to Environments in the Dongting Lake, With Implications for Ecological Management of River- Connected Lakes Affected by Dam Construction Baozhu Pan,a Haijun Wang,b Zhiwei Li,c Xuan Ban,d Xiaomin Liang,b and Hongzhu Wangb* aState Key Laboratory Base of Eco-hydraulic Engineering in Arid Area, Xi’an University of Technology, Xi’an 710048, China bState Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology Chinese Academy of Sciences, Wuhan 430072, China; [email protected] (for correspondence) cChangsha University of Science & Technology, Changsha 410004, China dKey Laboratory for Environment and Disaster Monitoring and Evaluation, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China Published online 00 Month 2016 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ep.12510 The Dongting Lake, a river-connected lake, plays a vital storage and water sources in the midstream of the Yangtze role in people’s living, agricultural production, and ecologi- River; (2) the lake can provide water for drinking and irriga- cal security of the Yangtze River basin. A systematic investi- tion; (3) the lake is critical for maintaining the unique and gation of macroinvertebrates was conducted in the Dongting diverse biota of the entire Yangtze ecosystem; (4) wetland Lake during May 2004 - January 2005. Altogether 65 taxa ecosystem of the Dongting Lake has become an important belonging to 27 families and 53 genera were identified. The tourism resource due to its natural landscape, unique biota, annual average density and biomass of total macroinverte- delightful climate, and beautiful scenery. Therefore, the brates were 265 ind/m2 and 2.40 g dry mass/m2, respective- Dongting Lake plays a key role in people’s living and agri- ly. It is demonstrated that seasonal variation existed in cultural production. environmental factors structuring macroinvertebrate assemb- In recent years, for the requirements of flood control and lages of the Dongting Lake. Hydrological parameters (i.e., power generation, a series of cascade hydropower stations flow velocity, water depth) were the driving factors for mac- have been constructed in the mainstream and tributaries of roinvertebrate assemblages in spring and summer, whereas the Yangtze River, among which the Three Gorges hydro- the concentrations of water nutrients (i.e., phytoplankton power station is the largest one in the world. The operation chlorophyll a, total dissolved phosphorus) played the leading of hydropower stations has changed the original processes role in governing macroinvertebrate assemblages in autumn of taking in - sending out water, as well as the original input and winter. After operation of the Three Gorges Dam in and output mode of sediment and nutrient in the river- 2009, the Dongting Lake may be confronted with the threat connected lakes [1,2]. After the operation of the Three of species diversity declining and assemblage structure Gorges Dam (TGD), replenishment ability of the Dongting changing. Thus, ecological restoration measures shall be put Lake to the Yangtze River has been strengthened [3]. In the forward. VC 2016 American Institute of Chemical Engineers Environ Dongting Lake, sediment deposition becomes slower due to Prog, 00: 000–000, 2016 reservoir intercepting sediment [4,5], and annual distribution Keywords: macroinvertebrates, environmental analyses, of the runoff becomes more uniform, especially, low water the Three Gorges Dam, the Dongting Lake period occurs ahead of time and prolongs [6,7]. The chang- ing hydrological and sediment regimes break dynamic equi- librium of the relation between river and lake, and change INTRODUCTION the microhabitat conditions in local area, which leads to corre- The Dongting Lake is the second largest freshwater lake sponding assemblages succession in the Dongting Lake. in China, and its inundation area shows great inter-annual Therefore, it is necessary to select aquatic indicators for variability. The Dongting Lake has several ecological service assessing the changing ecological status of the Dongting Lake. functions: (1) it is connected with the Yangtze River main- In freshwater waterbodies, there are several assemblages stream in the north of the lake, and connected with four such as phytoplankton, zooplankton, macroinvertebrates, tributaries (i.e., Xiang, Zi, Yuan, Li Rivers) in the south of the fish, and macrophytes. Among these biota, macroinverte- lake. The Dongting Lake is of great importance for flood brates are good indicators of long-term changes in environ- ments because of their confinement to the bottom, long life VC 2016 American Institute of Chemical Engineers cycles, and limited abilities to move [8–11]. So far, few Environmental Progress & Sustainable Energy (Vol.00, No.00) DOI 10.1002/ep Month 2016 1 Figure 1. Locations of the study lake in the Yangtze basin (A) and sampling sites in the Dongting Lake (B). studies on the benthic animals in Dongting Lake have been of the TGD to the aquatic ecological status, some specific reported. Previous studies have been mostly restricted to ecological restoration measures may be proposed for local water quality assessment using macroinvertebrates as indica- governments, e.g., increasing incoming discharge in non- tors in special year [12], assemblage structure of macroinver- flood season, strictly control pollution sources, and connect- tebrates in special lake region [13,14], and some biological ing river network within the Dongting Lake basin. groups of macroinvertebrates such as mollusks [15,16]. Thus, our article reports the results of a systematic investi- The construction of the TGD has three stages since 1990s. gation of macroinvertebrates in the Dongting Lake completed During the first construction stage, the damming of the Yang- in 2004–2005. The aim of our study was threefold: (1) to tze River happened in 1997. During the second construction describe the overall characteristics of macroinvertebrate stage, the TGD began to impound water and sediment dis- assemblages in the Dongting Lake; (2) to analyze the poten- charge in 2003, when water level in the reservoir rose to tial environmental factors influencing macroinvertebrate 135 m. During the third construction stage, the whole dam assemblages; (3) to put forward strategies of aquatic conser- was completed in 2009, when water level in the reservoir vation and management for the river-connected lakes. was raised to 175 m [17]. The Dongting Lake, as the first larg- est lake regulating runoff and sediment from the Yangtze STUDY AREA AND METHODS River, is invariably bearing the brunt from the TGD’s opera- The Dongting Lake is situated in mid-to-lower Yangtze tion (Chang et al., 2010; Hu et al., 2013). When the TGD was basin in the monsoon region of the East Asia subtropical under construction, ecological succession in the Dongting zone. Limnological variables of the Dongting Lake are as fol- Lake was a gradual process. As far as we know, there was lows: Area, 2432 km2 (33.0 m asl); annual mean water-stage no scientific research on ecological assessment in the Dongt- fluctuation, 5.9 m; annual mean precipitation, 1200– ing Lake during the period of the TGD construction, which 1450 mm; annual mean evaporation, 1174–1420 mm; impedes our understanding of the ecological succession pro- retention time, 18.2 days; annual mean water sediment con- cess of the river-connected lake. Once we know the impacts centration, 127 g/m3 [18], [19]. Locations and sampling sites 2 Month 2016 Environmental Progress & Sustainable Energy (Vol.00, No.00) DOI 10.1002/ep Table 1. Environmental variables (mean 6 SE) of study sites in the Dongting Lake. Spring Summer Autumn Winter Average T(C) 23.4 6 0.4 26.8 6 0.3 16.1 6 0.2 8.1 6 0.2 18.6 6 4.8 SS (kg/m3) 0.0213 6 0.0031 0.0277 6 0.0024 0.0155 6 0.0024 0.0142 6 0.0025 0.0197 6 0.0036 pH 7.6 6 0.1 8.1 6 0.1 7.7 6 0.1 8.0 6 0.1 7.9 6 0.2 Z (m) 3.5 6 0.4 4.9 6 0.7 2.5 6 0.2 2.3 6 0.4 3.3 6 0.7 ZSD (m) 0.56 6 0.03 0.55 6 0.03 0.62 6 0.11 0.75 6 0.10 0.62 6 0.05 U (m/s) 0.26 6 0.03 0.31 6 0.03 0.22 6 0.04 0.17 6 0.03 0.24 6 0.03 TN (mg/m3) 1564 6 264 1656 6 120 1147 6 123 1588 6 460 1489 6 133 TDN (mg/m3) 815 6 47 1445 6 122 895 6 115 765 6 225 780 6 182 TP (mg/m3) 213 6 17 88 6 10 96 6 16 155 6 18 138 6 34 TDP (mg/m3) 118 6 11 45 6 8136 4776 14 63 6 26 Chl a (mg/m3) 2.77 6 0.48 2.73 6 0.39 2.01 6 0.27 1.66 6 0.36 2.29 6 0.32 2 BMac (g/m )966 68 155 6 113 458 6 330 0 6 0 177 6 114 Note: T, water temperature; SS, suspended solids; Z, water depth; ZSD, water transparency; U, flow velocity; TN, total nitrogen concentration of water; TDN, total dissolved nitrogen concentration of water; TP, total phosphorus concentration of water; TDP, total dissolved phosphorus concentration of water; Chl a, phytoplankton chlorophyll a concentration; BMac, wet biomass of macrophytes.