Qilu Lake Research Articles

Land-use change in plateau lake basin and its impact on urban ecological security

Land-use change is a hot issue in global change research. Ecological security caused by land-use change at different spatial time scales is also one of the hot issues of research. This paper selects the plateau lakes in China as the study area, explores the land-use change in the basin from 1989 to 2015, and uses the pressure-state-response (PSR) model to analyze the ecological security of the Central Yunnan Basin qualitatively. According to the research, from 1989 to 2015, the annual change rate of integrated land-use dynamics in the basin was 0.66%; the 1989 and 2015 ecological safety indexes of Qilu Lake were 0.5912 and 0.5845, respectively, all in a “poor” safety state. From the perspective of the system as a whole, the pressure of natural and humanities has the most significant impact on the ecological security assessment of the basin. According to the research, it provides a theoretical basis for the ecological security construction of the plateau lakes in China.

Demarcation and administration of watershed ecological protection red line considering the ecological security pattern-A case of the Qilu Lake watershed, Yunnan Province

Demarcation and administration of watershed ecological protection red line considering the ecological security pattern-A case of the Qilu Lake watershed, Yunnan Province

A Holocene history of the Indian monsoon from Qilu Lake, southwestern China

Understanding the magnitude, nature, and forcing mechanisms of past abrupt changes in Indian Summer Monsoon (ISM) strength is central to characterizing future manifestations in the face of global climate change, particularly at centennial time scales. Here we summarize a 6200 year record of oxygen isotopes from Lake Qilu in Yunnan Province, China. The lake is sensitive to changes in precipitation-evaporation balance and precipitates calcite, potentially providing insight into past hydroclimate through oxygen isotope analysis. Beginning at 5200 cal years BP, oxygen isotopes shift to higher values, indicative of a period of aridity and lower lake levels which persist until 3600 cal years BP. Thereafter, lake levels are extraordinarily stable until 1500 cal years BP. At 1500 cal years BP, measurable anthropogenic impacts occur, resulting in the delivery of red, iron-rich catchment soil to the lake and higher oxygen isotope values. These changes are likely the result of land clearance for the expansion of agricultural activities. The Qilu record is remarkably consistent with the record from Xingyun Lake, 10 km to the north, strongly suggesting that regional climate drivers are responsible for the changes after 5200 cal years BP and then the stability from 3600 to 1500 cal years BP. Comparison of both these records with Dongge Cave illustrate the importance of evaporative enrichment in driving higher oxygen isotope values from 5200 to 3600 cal years BP.

Identification and remediation countermeasures of the Agriculture water problem in Qilu lake basin

In this paper, based on the characteristic of natural geography, hydrometeor, ecological environment and the development of economic and society on the Qilu Lake Basin, making full use of a lot previous data, including field measured data, investigation data, planning reports and historical materials, to study and analyze the evolution population, arable land, irrigation area, agricultural planting, the water surface of lake of Qilu Lake since 1280 A.D. The test was carried out in the variation trend of Qilu Lake’s precipitation, average temperature, relative humidity, reference crop evapotranspiration, water resources, and other factors during 1950∼2016. The results show that water resources shortage phenomenon of Qilu Lake Basin can be traced back to 400 years ago. Social progress and increasing population have promoted the continuous improvement of the agricultural replanted pattern, the large consumption of water resources and the pollution of agricultural non-point sources have caused the deterioration of the water environment of the Qilu Lake. Additionally, lake water appears three times greatly atrophy was caused by the reclaiming land from lakes and climate warming, and the fragility of water ecology is intensifying. The integration of resources should be combined with the system of lake-leader, then taking some measures like that saving water and reducing wastewater, reducing agricultural replanting index, delineation of ecological red line and management and protection of water coastline, water trans-valley project form other river basin, allocation of water resources and monitoring and control of water resources and so on. The adoption of these measures will gradually repair the water ecology, improve the water environment, improve the carrying capacity of water resources, and realize the green and beautiful countryside.

近30a杞麓湖面积变化遥感监测分析

近30a杞麓湖面积变化遥感监测分析

MNDWI和NDWI指数提取富营养化湖泊水体边界的对比研究

本研究基于Landsat 8 OLI卫星影像，采用云南省中部地区的5个湖泊，即滇池、抚仙湖、阳宗海、星云湖和杞麓湖作为研究对象，其中滇池、星云湖、杞麓湖是富营养化湖泊，比较了两种水体指数，NDWI和MNDWI提取湖泊水体边界的精确度。结果表明：由于近红外波段能够较好的区分植被和水体，但也带来了藻类覆盖的水域容易被误识别为植被的情况。因此，采用NDWI提取的富营养化湖泊水体面积比实际值偏小，中红外波段对水分含量较为敏感，在富营养化湖泊中采用该指数可以有效的区分陆地和水体，排除藻类的干扰。因此，MNDWI更适合用于富营养化湖泊的水体边界提取。 This study is based on the Landsat 8 OLI satellite images, and uses 5 lakes as sample, which are Dianchi Lake, Fuxian Lake, Yangzonghai Lake, Xingyun Lake and Qilu Lake, there are all located in the central region of Yunnan province, and Dianchi Lake, Xingyun Lake, Qilu Lake are eutrophic lakes. The accuracy of NDWI and MNDWI index for lake water boundary extraction was compared. The results show that the near infrared band can distinguish vegetation and water body better. But it has also brought the algae covered waters that can be mistakenly identified as vegetation. Therefore, the water area of eutrophic lake extracted by NDWI is smaller than the actual value. The infrared band is more sensitive to moisture content. Using this index in eutrophic lakes can effectively distinguish between land and water, eliminate algal interference. Therefore, the MNDWI index is more suitable for water boundary extraction in eutrophic lakes.

Production of biomass and lipids by the oleaginous microalgae Monoraphidium sp. QLY-1 through heterotrophic cultivation and photo-chemical modulator induction

A two-step strategy comprising heterotrophic cultivation and photo-chemical modulator induction was developed to enhance biomass and lipid accumulation in the oleaginous Monoraphidium sp. QLY-1, which was isolated from Qilu Lake in Yunnan Plateau. The algae were first cultivated heterotrophically to achieve high biomass concentration (5.54gL−1) with a lipid content of 22.47%. The cultivated algae were diluted, transferred to light environment, and treated with different chemical elicitors. Results showed that the lipid content increased to 36.68% after 3-day of photoinduction. The lipid content was further enhanced by 1.21, 1.32, and 1.29 folds in algal cells treated with nitrogen deficiency, 20gL−1 NaCl, and 5mM glycine betaine, respectively. The maximum lipid content (48.54%) and lipid productivity (121.27mgL−1d−1) were obtained in treatments with 20gL−1 NaCl and 5mM GB, respectively. This study proposes a strategy to efficiently produce lipids by using microalgae.

Concentrations of toxic metals and ecological risk assessment for sediments of major freshwater lakes in China

A systematic geochemical lake sediment survey has been carried out in major freshwater lakes in China. Surface lake sediment (0–20cm) at a density of 1sample/4km2 and deep lake sediment (150–180cm) at a density of 1sample/16km2 were collected and analyzed with standard procedures. This overview provides a current ecological risk assessment for toxic metal contamination (As, Cd, Cr, Cu. Hg, Ni, Pb, and Zn) in the surface sediments of major freshwater lakes in China. Lake sediment in China poses a moderate ecological risk on a nationwide basis using a potential ecological risk index (PERI). Mercury ranked as presenting the greatest ecological risk, followed by Cd, As, Pb, Cu, Ni, Cr, and Zn. Liangzi Lake was classified as having high ecological risk; Dalonghu Lake, Dianchi Lake, Dongting Lake, Fuxian Lake, and Qilu Lake as having moderate ecological risk; while the other surveyed lakes were classified as having low ecological risk. Uncertainties of risk assessment are also discussed by considering geochemical background, the eco-toxicity of metals and the sensitivities of local benthic communities. These comprehensive findings have provided valuable information for improvement of lake management and pollution prevention and control in China.

Dactylella qiluensis, a New Species of Aquatic Hyphomycete from China

Abstract A new Dactylella species lacking nematode-trapping devices was isolated from submerged wood during a survey of aquatic fungi in Qilu Lake, Yuxi, Yunnan province, China. Conidiophores are long and repetitive branched, forming 1–3 short conidia in sympodial arrangement at the apex. Conidia are commonly elongated fusoid, rostrate, slightly inflated at the middle, straight or curved, 5–9 septate, tapering evenly towards base, end cell elongate, tapering to a point at the distal, 88.9–143.1(120.8) × 8.2–11.2(9.9) µm, end cell long 22.4–40.2 µm. The new species is introduced, characterized and illustrated in this paper.

Monitoring of Water Quality Using Remote Sensing Techniques

Remote sensing techniques play increasingly important role over recent decades in both problems of global climate change and frequent deterioration of the status of aquatic ecology. In this paper, Landsat ETM+ imagery was used to monitors water quality in Kunming city, southwest China. Five over 30 square kilometers lakes which are Dianchi, Fuxian, Yangzong, Qilu and Xingyun Lake were extracted and investigated. Comparing spectra of different water quality, it can be conclude the reflectance of band 2 and band 3 change dramaticlly corresponding to different water quality, which are relate to the water pollutant. Therefore, the sum of band 2 and band 3 reflectance used as a water quality index was selected to detect water quality. Firstly, the remote sensing data was atmospheric corrected and the reflectance of band 2 and band 3 was added using band math. Secondly, density slice was applied to the processed sum image using suitable data ranges and colors, and six water quality level was outputed. Finally, the result image was projected and outputed. As shown from result, the water quality of Fuxian and Yangzong lake were the best, and Dianchi and Xingyun lake were the worst, Qilu lake was in the middle. Suitable water pollution controls and provention for Kunming lakes would be needed.

Threatened fishes of the world: Cyprinus pellegrini (Tchang, 1933) (Cypriniformes: Cyprinidae)

Common name: Datouli (in Chinese), “Big-head carp” or “Barbless carp” (in English). Conservation status: Endangered-China red data book of endangered animals (Wang et al. 1998). Identification: Deepest point of fish in lateral view in line with bony posterior margin to operculum; D:iv,15–18; A:iii,5; lateral line scales 34–37, upper transverse scale row between dorsal mid-line and lateral line 6–7, lower transverse scale row between lateral line and ventral mid-line 5 (Yang et al. 1966; Huang 1997). Illustration from Wu Xian-Wen (1977). Distribution: Endemic species in China and distributed only in Xingyun Lake and Qilu Lake of Yunnan Province (Wang et al. 1998; Li et al. 2008). Abundance: During the 1950s, it was an economically important fish of Xingyun and Qilu lakes; accounting for 70% of total fish production. Stocks have declined rapidly since the 1960s. Production in Xingyun Lake was 10% in 1966, 0.5% in 1986 and 0.1% in 1990 (Huang 1997; Wang et al. 1998). Habitat and ecology: Occurs in upper and mid-water habitats of high transparency. Feeds on plankton and, to a lesser extent, algae (Huang 1997). Reproduction: Spawning from April to September, mainly in May and June, in batches on aquatic plants; spawn sticky (Huang 1997). Threats: Introduced species that compete for food and habitat resources (Wang et al. 1998), overexploitation, habitat degradation and hybridization with other carp. Conservation action: No specific legal protection or conservation activity. Conservation recommendations: Scientific project to conduct a Population and Habitat Viability Assessment and produce a detailed Conservation Action Plan covering control of water pollution, improved management of the fishery, opportunities for assisted reproduction ex situ and reintroductions, as and when appropriate.

Threatened fishes of the world: Cyprinus pellegrini pellegrini Tchang, 1933 (Cyprinidae)

Common name: Boshi carp (or Barbless carp). Conservation status: Listed as a Grade II State Protected Species in China; listed as vulnerable species in China Red Data Book of Endangered Animal— Pieces (Yue and Chen 1998). Identification: Body elongate; head large and broad; mouth large and terminal; eyes on upper half of head; barbels absent or with a pair of papilla at corners of mouth; scales rather large. Lateral line scales 34–37. Dorsal fin grayish dark, paired and caudal fins light yellow; lower lobe of caudal fin red (Yue and Chen 1998). Illustration: Xianwen (1982). Distribution: Endemic to China, in plateau lakes, Xingyun Lake and Qilu Lake of the Nanpanjiang River system, Yunnan province (Li et al. 1995). Habit and ecology: Lives in upper and middle layers of the deep parts of lakes in calm water (Yue and Chen 1998). Filter-feeder, feeding mainly on zooplankton, but its feeding apparatus is less developed and less powerful (filters less water) than those of bighead and silver carp (Cao 1992). It is highly sensitive to low temperatures (Sun and Liang 2004). Reproduction: Spawning period from April to September, peak in May and June. Batch spawning, eggs adhere to hydrophytes (Yue and Chen 1998) in shallow water where their larvae grow (Jia et al. 2008). Its major population is located in Jiangchuan Hatchery now (Jia et al. 2008). Fecundity can reach up to 130,000 in 3 to 4 year old females (Yue and Chen 1998). Threats: Wild populations have declined dramatically in recent decades from environmental fluctuations; slow growth rate; habitat destruction and loss of spawning grounds by decreasing of hydrophytes because of declining water levels; overfishing; and especially the invasion of exotic species (Jia et al. 2008). The proportion of barbless carp in the total fish yield declined to 20% in the 1960s, to 10% in the early 1970s, and now to less than 1% since the 1980s (Huang 1997). Conservation action: Transplanting, domestication and artificial reproduction have been carried out in Jiangchuan County and Yuanjiang County of Yunnan province (Yue and Chen 1998). Conservation activities were conducted in Heilongjiang Fishery Institute of CAFS Environ Biol Fish (2009) 86:485–486 DOI 10.1007/s10641-009-9558-4

Sinopec building new cracking catalyst plant

A two-step strategy comprising heterotrophic cultivation and photo-chemical modulator induction was developed to enhance biomass and lipid accumulation in the oleaginous Monoraphidium sp. QLY-1, which was isolated from Qilu Lake in Yunnan Plateau. The algae were first cultivated heterotrophically to achieve high biomass concentration (5.54 g L−1) with a lipid content of 22.47%. The cultivated algae were diluted, transferred to light environment, and treated with different chemical elicitors. Results showed that the lipid content increased to 36.68% after 3-day of photoinduction. The lipid content was further enhanced by 1.21, 1.32, and 1.29 folds in algal cells treated with nitrogen deficiency, 20 g L−1 NaCl, and 5 mM glycine betaine, respectively. The maximum lipid content (48.54%) and lipid productivity (121.27 mg L−1 d−1) were obtained in treatments with 20 g L−1 NaCl and 5 mM GB, respectively. This study proposes a strategy to efficiently produce lipids by using microalgae.

Effects of land use on water quality of two high-altitude lakes and catchments in Yunnan Province, China

SUMMARY Reclaiming farmland from lakes in China in the 1950s damaged the water quality of many lakes. Tremendous efforts have been made since the late 1990s to restore vegetation around the damaged lakes. This paper examines water quality of Fuxian and Qilu Lakes and land-use characteristics within the two catchments in the high-altitude area of Yunnan Province, China. Landsat TM data acquired in 1989, 1994, 1999 and 2005 were used to extract land use and land cover (LULC) information. Measurements of five water quality indices (WQIs), BOD, COD, pH, TN and TP, for the same period of time were examined. The results showed that the area of residential and forest/shrub increased, whereas that of cropland and barren land decreased from 1989 to 2005 in both catchments. Qilu Lake was much more polluted than Fuxian Lake, and pollution worsened over time for both lakes. The differences in water quality between the two lakes were caused by differences in LULC composition and continued degradation in water quality was caused by intensive farming and urban sprawl. Unless the landscape is converted back to its pre-1950 composition and structure, water quality in both lakes cannot be significantly improved and will continue to threaten sustainable development in the region.

Threatened fishes of the world: Cyprinus ilishaestomus (Chen & Hwang, 1977) (cyprinidae)

Common name: Top-mouth carp (English), Longyan carp (Chinese). Conservation status: Critically endangered, Class II protected animal of Yunnan Province (Yue and Chen 1998). Identification: D.IV, 16–17; A. III, 5; P.I, 16–17; V.I, 8–9. Gill rakers: upper 20–22, lower 28–29 (Chu and Chen 1989). Body typically carp-like, mouth is superior, no barbels, body covered with large scales, eyes are large. Yellowish green dorsum, the abdominal region is silvery white (Yue and Chen 1998). Drawing by Wu XW (Wu 1982). Distribution: C. ilishaestomus is restricted to the Qilu Lake of Yunnan Province, China (Wang 1979). Abundance: Formerly an economically important fish, but its numbers dropped sharply since the 1970s and now it is almost extinct. Habitat and ecology: Dwells mainly in deep water. It is an omnivore, feeds on shrimps, small fishes and some aquatic plants. Threats: Habitat degradation is the critical threat, including water pollution and reduction of the lake area. Introduced grass carp, Ctenopharyngodon idella, grazed macrophytes heavily and reduced habitat and food of C. ilishaestomus. Overfishing also remains a threat to the species. Conservation action: No specific action has been adopted. Conservation recommendation: First, protect the ecological environment for the Top-mouth carp in Qilu Lake. In addition, biological research on population ecology, habitat requirements and reproduction are required.