Temporal and spatial variation and prediction of water yield and water conservation in the Bosten Lake Basin based on the PLUS-InVEST model

To comprehensively evaluate the alterations in water ecosystem service functions within arid watersheds,this study focused on the Bosten Lake Basin,which is situated in the arid region of Northwest China.The research was based on land use/land cover(LULC),natural,socioeconomic,and accessibility data,utilizing the Patch-level Land Use Simulation(PLUS)and Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)models to dynamically assess LULC change and associated variations in water yield and water conservation.The analyses included the evaluation of contribution indices of various land use types and the investigation of driving factors that influence water yield and water conservation.The results showed that the change of LULC in the Bosten Lake Basin from 2000 to 2020 showed a trend of increasing in cultivated land and construction land,and decreasing in grassland,forest,and unused land.The unused land of all the three predicted scenarios of 2030(S1,a natural development scenario;S2,an ecological protection scenario;and S3,a cultivated land protection scenario)showed a decreasing trend.The scenarios S1 and S3 showed a trend of decreasing in grassland and increasing in cultivated land;while the scenario S2 showed a trend of decreasing in cultivated land and increasing in grassland.The water yield of the Bosten Lake Basin exhibited an initial decline followed by a slight increase from 2000 to 2020.The areas with higher water yield values were primarily located in the northern section of the basin,which is characterized by higher altitude.Water conservation demonstrated a pattern of initial decrease followed by stabilization,with the northeastern region demonstrating higher water conservation values.In the projected LULC scenarios of 2030,the estimated water yield under scenarios S1 and S3 was marginally greater than that under scenario S2;while the level of water conservation across all three scenarios remained rather consistent.The results showed that Hejing County is an important water conservation function zone,and the eastern part of the Xiaoyouledusi Basin is particularly important and should be protected.The findings of this study offer a scientific foundation for advancing sustainable development in arid watersheds and facilitating efficient water resource management.

Carbon and Oxygen Isotopic Composition of Surface-Sediment Carbonate in Bosten Lake (Xinjiang,China) and its Controlling Factors

Bosten Lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inlet and the single outlet in the western part of the lake. The analytical results show that the carbon and oxygen isotopic composition of recent lake sediments is related to this specific lacustrine depositional environment and to the resulting carbonate mineralogy. In the southwestern lake region between the Kaidu River inlet and the Kongqi River outlet, carbon isotope composition （δ^13C） values of the carbonate sediment （-1‰ to -2‰） have no relation to the oxygen isotope composition of the carbonate （δ^18O） values （-7‰ to -8‰）, with both isotopes showing a low variability. The carbonate content is low （〈20%）. Carbonate minerals analyzed by X-ray diffraction are mainly composed of calcite, while aragonite was not recorded. The salinity of the lake water is low in the estuary region as a result of the Kaidu River inflow. In comparison, the carbon and oxygen isotope values are higher in the middle and eastern parts of the lake, with δ^13C values between approximately ＋0.5‰ and ＋3‰, and δ^18O values between -1‰ and -5‰. There is a moderate correlation between the stable oxygen and carbon isotopes, with a coefficient of correlation r of approximately 0.63. This implies that the lake water has a relatively short residence time. Carbonate minerals constitute calcite and aragonite in the middle and eastern region of the lake. Aragonite and Mg-calcite are formed at higher lake water salinity and temperatures, and larger evaporation effects. More saline lake water in the middle and eastern region of the lake and the enhanced isotopic equilibrium between water and atmospheric CO2 cause the correlating carbon and oxygen isotope values determined for aragonite and Mg-calcite. Evaporation and biological processes are the main reasons for the salinity and carbonate mineralogy influence of the surface-sediment carbonate in Bosten Lake. The lake water residence time and the CO2 exchange between the atmosphere and the water body control the carbon and oxygen isotope composition of the carbonate sediment. In addition, organic matter pollution and decomposition result in the abnormally low carbon isotope values of the lake surface-sediment carbonate.

High-Resolution Records of the Holocene Paleoenvironmental Variation Reflected by Carbonate and Its Isotopic Compositions in Bosten Lake and Response to Glacial Activities

The Early Holocene paleoclimate in Bosten Lake on the northern margin of the Tarim Basin, southern Xinjiang, is reconstructed through an analysis of a 953 cm long core （BSTC2000） taken from Bosten Lake. Multiple proxies of this core, including the mineral components of carbonate, carbonate content, stable isotopic compositions of carbonate, Ca/Sr, TOC and C/N and C/S of organic matter, are used to reconstruct the climatic change since 8500 a B.P. The chronology model is made by nine AMS 14C ages of leaves, seeds and organic matter contained in two parallel cores. The climate was cold and wet during 8500 to 8100 a B.P. Temperature increased from 8100 to 6400 a B.P., the climate was warm and humid, and the lake expanded. The lake level was highest during this stage. Then from 6400 to 5100 a B.P., the climate became cold and the lake level decreased slightly. During the late mid-Holocene, the climate was hot and dry from 5100 to 3100 a B.P., but there was a short cold period during 4400 to 3800 a B.P. At this temporal interval, a mass of ice and snow melting water supplied the lake at the early time and made the lake level rise. The second highest lake level stage occurred during 5200 to 3800 a B.P. The climate was cool and wet during 3100 to 2200 a B.P., when the lake expanded with decreasing evaporation. The lake had the last short-term high level during 3100 to 2800 a B.P. After this short high lake level period, the lake shrank because of the long-term lower temperature and reduced water supply. From 2200 to 1200 a B.P., the climate was hot and dry, and the lake shrank greatly. Although the temperature decreased somewhat from 1200 a B.P. to the present, the climate was warm and dry. The lake level began to rise a little again, but it did not reach the river bed altitude of the Konqi River, an outflow river of the Bosten Lake.

Organochlorine pesticides and polycyclic aromatic hydrocarbons in water and sediment of the Bosten Lake,Northwest China

We evaluated organic pollution in Bosten Lake, Xinjiang, China, by measuring the concentrations and distributions of organochlorine pesticides （OCPs） and polycyclic aromatic hydrocarbons （PAHs）. Water and sediment samples were collected from 19 sites 031-1319） in the lake for analysis. Our analytical results show that the concentrations of total OCPs in water ranges from 30.3 to 91.6 ng/L and the concentrations of PAHs ranges from undetectable （ND） to 368.7 ng/L. The concentrations of total OCPs in surface （i.e., lake bottom） sediment ranges from 6.9 to 16.7 ng/g and the concentrations of PAHs ranges from 25.2 to 491.0 ng/g. Hexachlorocyclohexanes （HCHs） and dichlorodiphenyltrichloroethanes （DDTs） account for large proportions of the OCPs. Low α- to γ-HCH ratios in both water and sediment samples indicate possible contributions from both industrial products and lindane. DDTs in water are probably from historical input, whereas DDTs in sediments are from both historical and recent inputs. Moreover, DDT products in both water and sediments were from multiple sources in the northwestern part of the lake（B11, B12, B13, and B14）. Fugacity ratios for DDT isomers （p,p＇-DDE and p,p＇-DDT） at these sites were generally higher than equilibrium values. These results suggest that the input from the Kaidu River and diffusion of DDTs from the sediment to the water are responsible for DDT pollution in the water. Lower-molecular-weight PAHs, which originate primarily from wood and coal combustion and petroleum sources, represent the major fraction of the PAHs in both water and sediment samples. Our findings indicate that OCPs and PAHs in Bosten Lake can be attributed primarily to human activities. A risk assessment of OCPs and PAHs in water and sediment from Bosten Lake, however, suggests that concentrations are not yet high enough to cause adverse biological effects on the aquatic ecosystem.

Anomalous propagation conditions of electromagnetic wave observed over Bosten Lake, China in July and August, 2014

Atmospheric duct is a common phenomenon over large bodies of water, and it can significantly affect the performance of many radio systems. In this paper, a two-month（in July and August, 2014） sounding experiment in ducting conditions over Bosten Lake was carried out at a littoral station（41.89°N, 87.22°E） with high resolution GPS radiosondes, and atmospheric ducts were observed for the first time in this area. During the two months, surface and surface-based ducts occurred frequently over the Lake. Strong diurnal variations in ducting characteristics were noticed in clear days. Ducting occurrence was found at its lowest in the early morning and at its highest（nearly 100%） in the afternoon. Duct strength was found increasing from early morning to forenoon, and reaching its maximum in the afternoon. But contrarily, duct altitude experienced a decrease in a clear day. Then the meteorological reasons for the variations were discussed in detail, turbulent bursting was a possible reason for the duct formation in the early morning and the prevailing lake-breeze front was the main reason in the afternoon. The propagation of electromagnetic wave in a ducting environment was also investigated. A raytracing framework based on Runge–Kutta method was proposed to assess the performance of radio systems, and the precise critical angle and grazing angle derived from the ray-tracing equations were provided. Finally, numerical investigations on the radar performance in the observed ducting environments have been carried out with high accuracy, which demonstrated that atmospheric ducts had made great impacts on the performance of radio systems. The range/height errors for radar measurement induced by refraction have also been presented, too, which shows that the height errors were very large for trapped rays when the total range was long enough.

APPLICATION OF REMOTE SENSING TECHNIQUE TO THE INVESTIGATION ON REED RESOURCES OF BOSTEN LAKE

It is efficient and reliable to investigate the reed resources of Bosten Lake in Xinjiang, characterized by complicated types of reed land and very different reed growth using colour infrared aerial photos, Landsat images and multi band imagery. At first, on the basis of Landsat images and relevant data, we analyzed the ecological environment of the studied area, the characteristics of reed land types and imaging mechanism to determine the program for abstracting remote sensing information and aerial photographic conditions:On the processed Landsat images and aerial photos, we considered typically geographic features and reed land types, preselected ground sampling sections and sites, then determined indexes classifying reed land types according to sampling data and image characteristics, established various interpretation keys, drew distribution maps of reed land types and measured the area of various types of reed land following geometric correction. On the other hand, based on sampling values and

Holocene lake deposits of Bosten Lake,southern Xinjiang,China

A 9.25-m-long sediment core from Bosten Lake, Xinjiang, provides detailed information about changes in the water budget and biological acticity over the last 8400 calendar years. The chronology is constructed from six AMS radiocarbon dates on the terrestrial plant remains. Based on analyses of TOC, CO3, detrital compounds and biogenic SiO2, lake level fluctuations and periods of remarkably-negative water budget appeared at 8.4—8.2 cal ka, 7.38—7.25 cal ka, 5.7—5.5 cal ka, 3.7—3.4 cal ka and 3.3—2.9 cal ka, respectively. As they are in-phase with low lake levels at Sumxi Co and Bangong Co in western Tibet Plateau and with paleolakes in Inner Mongolia, a climate-induced change to somewhat drier and warmer conditions is inferred. A further drop in lake level after 1320 AD of about 200 yr duration may be attributed to a negative water balance prior to the main phase of the Little Ice Age. Deep and stable lake phases of 1500 yr and 1800 yr duration at 7.2—5.7 cal ka and 5.5—3.7 cal ka coincide with maximum moisture during the Holocene Megathermal in China. The long term trend towards aridity since about 4.3 cal ka can clearly be recognised. The reduced water budget of Bosten Lake from 640—1200 AD may be attributed to local effects.

Humid Little Ice Age in arid central Asia documented by Bosten Lake, Xinjiang, China

Short sediment cores retrieved from Bosten Lake, the largest inland freshwater lake in China, were used to explore humidity and precipitation variations in arid central Asia during the past millennium. The chronology of the cores was established using 137Cs, 210Pb and AMS 14C dating re- sults. Multi-proxy high-resolution analysis, including pollen ratios of Artemisia and Chenopodiaceae (A/C), carbonate content and grain size, indicates that the climate during the past millennium can be divided into three stages: a dry climate between 1000―1500 AD, a humid climate during the Little Ice Age (LIA) (c. 1500―1900 AD), and a warm dry period after 1900 AD. On centennial timescales, the climate change in northwestern China during the past 1000 years is characterized by oscillations between warm-dry and cold-humid climate conditions. All the proxies changed significantly and indi- cate increased precipitation during the LIA, including increased pollen A/C ratios and pollen concen- trations, decreased carbonate content and increased grain size. The humid period during the LIA re- corded by the Bosten Lake sediments is representative of arid central Asia and is supported by nu- merous records from other sites. During the LIA, the water runoff into the Keriya River and Tarim River in the Tarim Basin increased, while the ice accumulation in the Guliya ice core increased. Additionally, the lake levels of the Aral and Caspian Sea also rose, while tree-ring analysis indicates that precipita- tion increased. We hypothesize that both the lower temperature within China and the negative anomalies of North Atlantic Oscillation (NAO) during this period may have contributed to the humid climate within this area during LIA.

ISOTOPIC EVIDENCE FOR HOLOCENE CLIMATIC CHANGES IN BOSTEN LAKE,SOUTHERN XINJIANG,CHINA

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基于演化博弈的新疆博斯腾湖流域生态补偿机制研究

流域生态补偿能有效解决资源开发利用过程中产生的外部性问题,对促进流域经济-社会-生态协同发展具有重要意义。基于演化博弈理论分析上级政府与上、下游地方政府的三方动态演化情景,以新疆博斯腾湖流域为研究对象,设定流域生态补偿机制。结果表明:上级政府对违约方征收的罚金高于流域上游生态保护成本和下游生态补偿金时,上、下游才能达到“保护”和“补偿”策略的稳定均衡状态。基于演化结果测算的博斯腾湖生态补偿金、生态保护成本分别为2.64×10^(7)、2.20×10^(7)元/a。采用“关键污染因子超标赔偿法”确定以COD_(Mn)、NH_(3)-N、TP三类污染物超标为评价依据的处罚标准分别为1312.51、9181.56、13115.08元/t。

基于模糊隶属度分布函数的博斯腾湖景观适宜水位确定

采用层次分析法识别博斯腾湖景观关键点,基于湖泊特征水位分析,构建了景观关键点水位和景观适宜度的模糊隶属度分布函数,计算了不同季节博斯腾湖景观适宜水位范围。结果表明:湖泊水质、年旅游业收益是识别博斯腾湖景观关键点的主要因素;博斯腾湖最佳景观水位为1046.70 m,低警戒水位为1045.00 m,高警戒水位为1047.90 m,低、高破坏边缘水位分别为1045.40 m和1047.40 m;不同季节博斯腾湖景观适宜水位存在差异,春季和秋季景观适宜水位范围为1045.90~1047.16 m,夏季为1046.00~1047.00 m,冬季为1045.85~1047.25 m。

Characteristics of Stable Isotopes in an Inland Lake and Their Implications for Water Management in Northwestern China

Bosten Lake is the largest inland freshwater lake in China, functioning as a critical control and allocation facility for agricultural, industrial, ecological and social development in southern Xinjiang in northwestern China. The distribution of stable isotopes, spatial and temporal variations of δ18O, and hydrograph separation of Bosten Lake and its principal recharge rivers—the Kaidu River and the Huangshuigou River—were analyzed using isotope composition. Hydrograph separation indicated that Bosten lake water comprised four components as follows: river runoff, groundwater, agricultural and industrial drainage, and local precipitation. Their contributions were 31%, 35%, 25%, and 9%, respectively. Irrigation drainage and industrial wastewater, enriched high TDS, were the main factors affecting the water quality of Bosten Lake. The δ18O of lake water, which was significantly reduced compared with river water, remained below the local meteoric water line (LMWL), indicating strong evaporation in the lake, especially during summer. The spatial and temporal distribution of δ18O exhibited slow water circulation in the lake. Both the Kaidu River and the Huangshuigou River depend on alpine precipitation and glacier snow, especially the Kaidu River, where ice-snow-melt water accounts for 43% of the river runoff. These rivers are sensitive to climate change. The Bosten Lake inflows would be reduced by the decrease in river runoff and groundwater under future climate change. To improve water quality and reduce evaporative loss, the amount of wastewater should be strictly restricted by local government, and water diversions from Bosten Lake should be concentrated between May and September.

基于卫星测高和实测数据的博斯腾湖水位变化分析

湖泊水位是湖泊水文观测必不可缺的要素,直接关系到湖泊物质交换和能量平衡,对研究湖泊运动和区域气候环境变化至关重要。为了掌握内陆湖泊水位的变化过程和空间特征,以新疆博斯腾湖为例,综合Jason-1&2、ENVISat&ERS、ICESat-1、ICESat-2等卫星测高资料,提取博斯腾湖湖泊水域瞬时水位和日均水位,并根据Hydroweb水位记录和1975-2020年博斯腾湖湖泊水位观测及水域面积数据,检验Jason-1&2、ENVISat&ERS、ICESat-1、ICESat-2测高数据的估计精度。借助趋势面分析方法,分析博斯腾湖水域水位变化的空间差异和特征。结果表明:Hydroweb水位记录、Jason-1&2、ENVISat&ERS、ICESat-1、ICESat-2卫星资料估计湖泊日均水位的绝对误差分别为0.24、0.34、0.28、0.18、0.08 m;2020年博斯腾湖年均水位为1048.10±0.12 m,与1975年年均水位相比增加了0.70±0.15 m;湖泊瞬时水位在空间尺度上存在一定水位差,ICESat-2测高数据能准确地描述博斯腾湖水域表面高程和水位变化速率的空间异质性。

湖泊生态服务生产函数构建研究--以博斯腾湖为例

湖泊生态系统服务(LES)在维持区域乃至全球生态安全格局中发挥重要作用,是目前生态系统服务研究的热点之一。由于湖泊面广量大、类型丰富、区域差异大及基础数据较为缺乏等原因,适用于LES定量评估且较为便捷、可行的模型方法较少。本文以博斯腾湖为例,基于生态系统最终服务与关键特征指标构建湖泊生态服务生产函数(LEPF),用于定量评估湖泊生态系统服务价值(LESV)并甄别关键特征指标的贡献度。结果表明:(1)博斯腾湖19902019年生态系统最终服务年均价值量为2226.84亿元,总体呈“上升下降上升”的变化趋势,气候调节、防洪蓄水为主导生态系统服务;(2)LEPF拟合结果较好地反映了5类关键特征指标对LESV的贡献度,从高到低依次为:湖泊水位>蒸发量>面积>水生植被面积>综合营养状态指数;(3)5类关键特征指标中水位的产出弹性较高,表明水位波动与生态系统最终服务价值变化密切相关。

河流输入对博斯腾湖溶解性有机物组成的时空影响

博斯腾湖是我国西北干旱区最大的内陆吞吐型淡水湖,近年来随着流域人类活动与污废水排放的增加,湖泊生态系统和周围居民的饮用水安全已经受到了严重影响,需重点关注河流输入对湖泊水质的影响。对夏秋两季的实测有色溶解有机物(CDOM)三维荧光光谱进行平行因子分析,解析出博斯腾湖CDOM三种组分:陆源类腐殖质组分C1、类酪氨酸组分C2和类色氨酸组分C3;同时,基于Pearson相关性分析了夏秋两季河流输入对博斯腾湖DOM的影响。结果表明,不同季节河流输入对博斯腾湖DOM的影响不同且与河流水质季节性变化直接相关。夏季开都河入湖水主要来自冬季积雪融水,携带大量陆源类腐殖质入湖,而秋季主要为冰川融水,随着入湖流量增加,携带陆源类腐殖质含量降低,整体表现为河口附近DOM浓度夏季高、秋季低。解析出的三种组分C1、 C2与C3在湖西部开都河和黄水沟入湖处含量较高,且三种组分受季节性的影响较为相似。同时对开都河河口附近采样点和其他区域采样点的DOM与电导率进行相关性分析,发现外部河流输入对博斯腾湖DOM的影响主要集中在河口附近,且河口附近区域DOC与CDOM关系显著,可以先遥感反演CDOM再估算DOM含量。研究不同季节河流输入对博斯腾湖溶解性有机物组成的影响对保护湖泊生态环境和提升湖泊水质具有十分重要的意义。

博斯腾湖鱼类密度季节变化及其环境影响因素

为了解博斯腾湖鱼类资源现状及其与环境因素的关系,于2019年5月(春季)、7-8月(夏季)、10月(秋季),采用分裂波束回声探测仪(Simrad EY60,120 kHz)开展全湖水声学探测,并对水环境指标进行现场测量。结果显示,博斯腾湖鱼类密度在夏季最高,平均值为(8783±2611)ind./hm^(2);春季和秋季间无显著性差异,平均值分别为(709±141)、(743±499)ind./hm^(2)。根据目标强度与体长关系经验公式推算,春季、夏季和秋季鱼类的平均体长分别为8.8、4.0和5.1 cm。相关分析结果显示,博斯腾湖鱼类密度与水温和电导率呈极显著正相关(P<0.01),而与透明度呈显著负相关(P<0.05)。随机森林模型的特征重要性排序结果显示,电导率是鱼类密度最重要的预测因子,其次为溶解氧、盐度和水温等。推测鱼类密度的季节变化与环境变化、食物来源、繁殖习性等因素密切相关,环境因子可能通过直接或间接的方式影响鱼类的生态环境需求。

基于三生空间的博斯腾湖流域生境质量时空演变及预估

生境质量是衡量区域生态环境优劣的重要指标,对干旱半干旱流域地区的生境质量进行研究具有重要的理论和现实意义。基于自然地理、遥感影像等多源数据,运用重心迁移、InVEST模型等研究方法,揭示1980—2020年博斯腾湖流域生境质量的时空演变规律,采用FLUS模型对2025年和2030年的土地利用时空演变进行模拟,阐明不同土地利用变化情景下生境质量时空演变格局。结果表明:(1)1980—2020年,博斯腾湖流域生境质量平均值由0.546降至0.521。高质量区域面积大幅缩减,区域重心向北迁移;生境低质量区域面积增加且重心向东北方向迁移。流域总体生境退化强度有所减弱。(2)自然发展情景下,流域工业生产用地和其他生态用地面积大幅增加;生态优先发展情景下,流域水域生态用地发展趋势由减转增,并向草地生态用地和其他生态用地迁移;经济优先发展情景下,焉耆盆地与绿洲平原的城镇生活用地和工业生产用地边界得到扩张。研究结果可以为干旱半干旱流域地区土地利用规划及生境质量改善提供科学依据。

基于多端元解混模型的博斯腾湖区域植被和水域时空变化特征及趋势分析

湿地高精度动态变化遥感监测,对于湿地保护和恢复具有重要的实践意义。以新疆博斯腾湖湿地为研究对象,运用多端元混合像元分解(Multiple endmember spectral mixture analysis,MES⁃MA)模型提取Landsat影像中植被、水体和裸地面积,通过无人机影像验证精度后,结合趋势分析法探明2000—2022年博斯腾湖湿地时空变化特征及趋势。结果表明:(1)通过无人机影像重采样精度验证的MESMA分类结果中植被像元拟合优度(R2)为0.75,水体像元R2为0.84,表明分类结果符合实际地物情况。(2)2000—2022年博斯腾湖湿地植被面积共增加536.65 km^(2),增加了183.14%;水域面积则减少595.76 km^(2),减少了37.07%;裸地面积共增加99.12 km^(2),增加了25.42%。(3)博斯腾湖湿地植被面积呈增加趋势的区域占总面积的30.6%,位于大湖区西北部和小湖区北部;反之水域面积呈减少趋势的区域占总面积的34.6%,位于大湖北岸、东岸及小湖湿地。准确掌握博斯腾湖湿地时空变化情况及其趋势,可对干旱区内陆湿地监测与保护提供参考依据。

不同时空尺度下土地利用对博斯腾湖水质的影响

水资源是区域社会经济发展的重要战略资源,尤其在地表水资源稀缺的干旱区,湖泊的水文循环调节、水资源调蓄、水质净化等作用在干旱区显得尤为重要。为研究干旱地区不同空间尺度土地利用对内陆干旱湖泊水质的影响,以博斯腾湖为研究对象,分析湖泊水质时空变化特征,并通过与周边六期土地利用进行统计相关分析,阐明土地利用变化对不同水质指标的影响。结果表明:2005—2019年博斯腾湖水质有较大改善。根据标准,氨氮的浓度在地表水环境I~II类水水质标准之间,高锰酸盐指数和总磷处于地表水环境Ⅱ~Ⅲ类水水质标准之间,但湖水总矿化度仍大于1000 mg/L的淡水标准,属于微咸水。相关性分析表明:耕地、城市、未利用地等面积占比与水质指标之间具有强相关性;多元线性回归和冗余分析结果表明:有效改善水质主要需要从城市用地、耕地和草地三种土地类型规划和布局着手。

基于遥感影像的博斯腾湖水位反演

基于1972年~2021年间博斯腾湖140景Landsat卫星影像,提取出水域面积和湖岸线,并结合1955年~2009年水位数据,分别建立面积、岸线形状系数与水位的相关曲线,实现基于实时遥感数据对博斯腾湖水位的动态监测;文章主要反演博斯腾湖1972年~1975年、1990年~2001年、2010年~2021年缺测日期的历史水位,总体上,博斯腾湖水位在1979年~2021年间呈“下降-上升-下降-上升”的趋势,水位上下波动较大。