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The Study on the Grey Scale Control in Chinese Font Design with Algorithm
The Study of Quality of Life and Quality Adjusted Survival in Patients with Advanced Cancer
A study with sensory evaluation and GC-MS/HPLC analysis on changes of flavor compounds in mutton during storage
In: CyTA: journal of food, Band 22, Heft 1
ISSN: 1947-6345
Effects of environmental regulation on the upgrading of Chinese manufacturing industry
In: Environmental science and pollution research: ESPR, Band 26, Heft 26, S. 27087-27099
ISSN: 1614-7499
Machine vision based plant height estimation for protected crop facilities
In: Computers and electronics in agriculture: COMPAG online ; an international journal, Band 218, S. 108669
Inter- and intra-city networks: how networks are shaping China's film industry
In: Regional studies: official journal of the Regional Studies Association, Band 55, Heft 3, S. 533-545
ISSN: 1360-0591
Simulation study on crucial parameters of long-compressive and short-suction ventilation in large section roadway excavation of LongWangGou coal mine
In: Environmental science and pollution research: ESPR, Band 30, Heft 3, S. 6435-6453
ISSN: 1614-7499
Effects of Exercise Intervention on Preventing Letrozole-Exposed Rats From Polycystic Ovary Syndrome
In: Reproductive sciences: RS : the official journal of the Society for Reproductive Investigation, Band 24, Heft 3, S. 456-462
ISSN: 1933-7205
The impact of technological innovation and financial development on environmental pollution in gulf cooperation council – A linear and nonlinear ARDL approach
In: Environmental science and pollution research: ESPR, Band 30, Heft 53, S. 114294-114309
ISSN: 1614-7499
Effects of aquaculture on the shallow lake aquatic ecological environment of Lake Datong, China
In: Environmental sciences Europe: ESEU, Band 34, Heft 1
ISSN: 2190-4715
Abstract
Background
The restoration of lake ecosystems requires a good knowledge of the lake's history and the driving mechanism of environmental changes. In this study, we used Lake Datong, the largest inland lake in Hunan Province China, as an example to study the effects of aquaculture, based on historical data of aquatic creature, diatom inferred-total phosphorous (DI-TP) data, and an Ecopath model. Lake Datong has undergone several stages of aquaculture from 1980, with a rapid increase in fish production and fish feed supplementation at each stage. Its water quality has deteriorated since the introduction of aquaculture and the lake has become moderate eutrophic status.
Results
According to the DI-TP data, before 1930, Lake Datong was in a mesotrophic status (50–60 μg/L DI-TP). Between 1930 and 1980, the number of nutrient-tolerant species increased slightly, which indicates a nutrient increase in the lake (66–83 μg/L DI-TP). From the 1980s to 2010 and especially since 2000, eutrophication increased rapidly, with eutrophic species dominating the diatom assemblage, such as Stephanodiscus hantzschii, S. minutulus, and a sudden decrease in Aulacoseira granulata (< 10%). The annual average DI-TP concentration was 202 μg/L. After 2010, DI-TP decreased to 127–152 μg/L. In 2019, consumer biomass in Lake Datong was very low because the large-scale aquaculture was restricted by local government. The biomass of submerged macrophytes was relatively high, indicating that excessive primary producers had not been used by consumers and therefore, had not entered the food web. This led to a reduction in the energy transfer efficiency (TE) of the ecosystem.
Conclusions
The succession of the water ecosystem of Lake Datong is reappeared by DI-TP analysis and historical reference data. Lake Datong has experienced four stages of eutrophication succession following the introduction of aquaculture activities, with dramatic changes in the composition and biomass of its aquatic creatures. After comprehensive management in 2017, the consumer biomass of Lake Datong was at a relatively lower level, and the biomass of submerged macrophytes was higher, meaning a large quantity of primary producers had not been used by consumers, thus had not entered the food web, which consequently reduces the energy TE of the ecosystem. Future management needs to pay attention to making a suitable macrophyte harvest plan, stocking herbivorous and omnivorous fish, and establishing rational fishing, which can not only enhance the energy flows and nutrient cycling of the ecosystem, but also improve the food web structure. Our results provide important reference values and theoretical support for decision-makers and stakeholders in the subsequent management of similar shallow lake-water ecosystems.
The impact of multiple metals exposure on the risk of developing proliferative diabetic retinopathy in Anhui, China: a case–control study
In: Environmental science and pollution research: ESPR, Band 30, Heft 52, S. 112132-112143
ISSN: 1614-7499