我国不同营养状态湖泊沉积物有机磷形态分级特征研究

研究了我国不同区域的7个不同流域特征、生态结构、污染程度的湖泊表层沉积物中有机磷（P_o）形态的分布特征,分析了P_o各组分与沉积物其他组分的关系和生物有效性. 不同湖泊沉积物中P_o相对含量的差异表明其来源和生物地球化学循环的不同,不同湖泊沉积物中有机质（OM）与P_o表现出显著相关关系（R>²=0.80,p>＜0.01）,除杞麓湖外,其它湖泊的OM与活性P_o、中活性P_o和非活性P_o也表现出显著相关关系（R>²分别为0.85、0.52、0.80,p>＜0.01）. 沉积物中有机磷中以中活性有机磷和非活性有机磷为主,其含量分别占总P_o的15.12%～66.73%和27.99%～77.72 %,活性P_o的平均相对含量为6.1%. 不同P_o组分的相对含量顺序为：residual P_o> HCl-P_o >fulvic acid-P_o>humic acid-P_o> NaHCO₃-P_o,平均的相对比例为8.3∶3.1∶2.2∶1.8∶1.0. 活性P_o和TP、P_i、P_o、NaHCO₃-P_i、NaOH-P_i呈显著正相关,非活性P_o与TP、P_o、NaOH-P_i呈显著相关,说明活性P_o很容易转化为生物可利用磷,同时非活性P_o也可能成为生物可利用磷的潜在源,非活性P_o只是化学溶解上的相对“惰性”,它仍具有潜在的生物活性.     

沉积物中磷形态与湖泊富营养化的关系

应用乙二胺四乙酸法对长江中下游太湖、巢湖和龙感湖等3个湖泊表层沉积物中磷的形态进行连续提取和测定.结果发现,在表层沉积物中,3个湖泊钙磷的百分含量比较接近,占总磷的30%左右,太湖和巢湖铁磷的百分含量显著高于龙感湖,而龙感湖有机磷的相对含量较高,可达40%~50%.这3个湖泊沉积物中有机磷形态差别十分明显,其中太湖沉积物中的有机磷主要以酸可提取有机磷形式存在,巢湖沉积物中酸可提取有机磷约占总有机磷的一半,而龙感湖的有机磷大部分与腐殖酸结合.沉积物中酸可提取有机磷的释放可能又是一个导致湖泊富营养化的重要过程.     

典型城市浅水湖泊沉积物磷形态的分布及与富营养化的关系

应用乙二胺四乙酸法对典型城市浅水湖泊:玄武湖、莫愁湖和大明湖的表层沉积物中磷的形态进行连续提取和测定.研究表明,表层沉积物中铁磷和钙磷是磷的主要存在形态,占总磷的80%左右,玄武湖和莫愁湖的铁磷明显高于大明湖,可达30%～40%.3个湖泊表层沉积物中有机磷形态以碱可提取有机磷为主,酸可提取有机磷含量较低,但其与总磷的比值可以较好地反映湖泊富营养化程度.     

第二阶梯湖泊富营养化自然地理因素及效应

为了明晰影响我国地形地貌第二级阶梯湖泊富营养化的主要自然地理驱动因素,为湖泊富营养化的有效治理提供参考,采用曲线回归方法分析了位于我国第二级阶梯的云南和新疆湖泊中Chl-a以及营养状态综合指数(TLI)与自然地理特征的相关性.结果表明,平均水深、海拔以及年均温与TLI指数具有较好的相关性,拟合模型分别符合三次/对数模型、二次模型和三次模型.Chl-a与年平均日照时数具有较好的相关性,拟合模型符合二次/三次模型.分析富营养化效应,藻类生长对透明度的影响以及营养物质对浮游藻类的生态效应(Chl-a/TP),结果发现,新疆湖泊中Chl-a与透明度呈倒数关系,云南湖泊中Chl-a与透明度呈幂函数关系;Chl-a与总磷的线性方程的斜率分别为177.595(云南)和222.758(新疆).影响我国第二级阶梯湖泊富营养化的主要自然地理驱动因素是湖泊的平均水深、海拔、年均温度及年平均日照时数,透明度与Chl-a含量的相关性以及营养物质TP对浮游藻类的生态效应存在区域差异.     

察汗淖尔湖泊面积变化及其对气候的响应分析

以察汗淖尔流域为研究对象,基于1990—2020年Landsat遥感影像,通过归一化水体指数（MNDWI）结合人工目视解译的方法提取察汗淖尔31年的丰水期湖泊面积并分析其演化规律。选取化德、尚义和商都3个气象站点的月气温、降水、蒸发量和相对湿度数据,采用线性倾向估计法和Mann-Kendall检验法分析了气候要素的变化趋势,并利用主成分分析和相关性分析法综合说明了察汗淖尔湖泊面积对气候因子的响应关系。结果表明:1）31年间,察汗淖尔流域呈气温上升、降水量下降、蒸发量上升的暖干化趋势;2）1990—2020年察汗淖尔湖泊面积经历稳定、减少、增长、再减少,4个变化阶段,湖泊面积于1991年达到最大49.72 km2,于2005年达到最小0.074 km2,整体呈下降趋势;3）湖泊面积对气候的响应迅速,夏季降水量和夏季蒸发量为影响丰水期湖泊面积的主要因素,同时也是造成湖泊季节性变化明显的主要因素。     

我国湖泊系统氮磷时空变化及对富营养化影响研究

本文收集整理了32篇已公开发表的学术论文的湖泊富营养化有效监测数据约140组,对湖泊氮磷时空特征和富营养化的关系进行分析。结果表明,我国湖泊总氮(TN)和总磷(TP)的变化范围分别为0.11~29.2 mg/L和0.006~1.04 mg/L,其中氮的变异性比磷大。TN/TP的变化范围在0.86~84,几何平均值为16.43,这说明磷素是我国湖泊富营养化的一个主要限制因子。TN与纬度存在极显著的相关关系,随着纬度的升高,TN含量极显著地减少,但TN与经度的相关关系较弱(p=0.126),这可能与氮在经度上变异性大有关。TP与纬度和经度的相关关系都达到显著水平,随着经纬度的升高,TP显著地减少。TN/TP与经纬度也都存在显著的相关关系,随经度和纬度的升高,我国湖泊的TN/TP显著升高,表明磷素富集可能是造成南方湖泊的富营养化程度高的重要原因。我国湖泊水体氮素和磷素在化学计量上的变化,可能与我国目前湖泊富营养化频发密切相关。自上个世纪90年代至今,我国湖泊磷素含量上升极为显著,但氮素则变化不大(p=0.275),从而引起TN/TP显著下降,所以,解决我国湖泊富营养化问题的关键在于"磷"素的输入控制。     

我国湖泊营养物基准的制定方法研究

湖泊富营养化的程度日益严重,已经对人类的生产生活、水生动植物的生存造成了危害。西方一些发达国家尤其是美国已经制定了水体水质基准,形成了一系列的基准制定的方法体系,建立了水质的管理体制。文章描述了我国的湖泊富营养化的现状、美国营养物基准的研究进展;列举了几个能够辅助基准制定的数学模型,探讨了我国的湖泊富营养化基准的制定方法步骤;通过几种模型的比较,并结合我国各方面的特点,确定我国基准制定中参照状态向基准的转化方法以及基准模型的应用和成果。     

湖泊底泥中磷形态及分布特征研究

对湖泊底泥磷进行研究分析,结果表明:沉积物PO3-4含量约为350 mg/kg;有机磷Or-P含量约为226.19 mg/kg,无机磷Fe-P、Ca-P分别为112.23~166.14 mg/kg,115.42~130.11 mg/kg,底泥中各形态磷的平均浓度由高到低顺序为:Or-P>Fe-P>Ca-P>De-P>Ex-P>Oc-P>AI-P;对不同形态磷进行相关性分析,结果表明:TP与IP、Fe-P和Ex-P相关性显著;底泥生物有效磷含量为312.65~410.16 mg/kg;上覆水TP与沉积物TP浓度也存在一定相关性。     

我国湖泊富营养化治理历程及策略

我国湖泊富营养化治理经历了从单一的调查诊断、控源治污等向湖泊综合治理和以湖泊生态安全和绿色流域建设为核心的流域综合治理转变,取得了阶段性成效,但我国湖泊富营养化问题依然严峻,治理过程中仍然存在着污染物削减能力不足、流域产业结构和布局不合理及管理体制不完善等诸多困难和问题。现阶段应实现湖泊富营养化治理"三大战略"转变,建立技术、政策、经济、法律等多手段联用的湖泊流域综合管理和治理体系,优先保护水质良好和生态脆弱湖泊,推动湖泊自然资本核算机制,建立湖泊流域经济可持续增长新模式,推进流域经济社会生产生活方式转变,构建湖泊流域生态文明体系。     

基于地理分区及神经网络的湖泊水库富营养化研究

构建了一个基于地理分区及神经网络的湖泊水库富营养化综合评价体系.以美国环境保护署Nutrient Criteria Database数据库为参照对象,有针对性地研究我国湖泊水库的情况,首次提出了基于地理分区的简易评价标准,对不同地理特征的水体富营养化临界值进行了定量研究.同时本研究还建立了基于神经网络的富营养化评价模型...     

我国东部与云贵湖区富营养化控制标准对比研究

以我国东部湖区及云贵湖区主要湖泊2005~2008年的监测数据和国际公认的湖泊富营养化叶绿素a 含量分级为基础,通过频率统计方法,对叶绿素a、总氮(TN)、总磷(TP)、透明度(SD)和高锰酸盐指数(CODMn)进行了统计分析,并根据反退化原则,计算了两湖区湖泊富营养化控制指标的建议值.结果表明,东部湖区湖泊富营养化控制标准的建议值为TN:1.65mg/L,TP:0.100mg/L,SD:0.45m,CODMn:4.50mg/L;云贵湖区为TN:1.00 mg/L,TP:0.045 mg/L,SD:1.10m,CODMn:4.00mg/L.云贵高原湖区氮磷营养盐控制指标值绝对值低,相应控制标准比东部平原湖区严,主要原因是东部平原湖区受人类活动影响强烈,目前的水环境总体质量劣于云贵湖区.     

Irrigation system and land use effect on surface water quality in river, at lake Dianchi, Yunnan, China

The surface water samples were collected in river Dahe and its tributaries, which flow into severely eutrophic lake Dianchi, Yunnan Province, China, in order to elucidate factors controlling water quality fluctuations. The temporal and spatial distribution of water quality tendency was observed. The water quality of each river is dependent on the hydrology effect such water gate and circulating irrigation system. We must consider the hydrology effect to accurately understand water quality variations of river in this study field. In river without highly circulating irrigation system or water gate effect, the downstream nitrate nitrogen (NO₃-N) concentration increase occurred in area dominated by open field cultivation, whereas the NO₃-N concentration was constant or decreased in area dominated by greenhouse land use. This result suggests that greenhouse covers the soil from precipitation, and nitrate load of greenhouse could be less than that of open field cultivation while the rainfall event. In the upper reaches of river, where is dominated by open field cultivation, there were no sharp increase dissolved molybdate reactive phosphorus and total phosphorus concentration, but P load was accumulated in the lower reaches of river, whose predominant land use is greenhouse. Although the P sources is unclear in this study, greenhouse area may have potential of P loads due to its high P content in greenhouse soil. Considering hydrology effect is necessary to determine what the major factor is influencing the water quality variation, especially in area with highly complicated irrigation system in this studying site.     

滇池、洱海、泸沽湖浮游植物研究综述

综述了近年来研究者们对云南滇池、洱海、泸沽湖三大高原湖泊的浮游植物调查研究成果,揭示了湖泊水质类型、富营养化程度与浮游植物的种类、优势种、数量之间的关系。     

我国湖泊富营养化防治与控制策略研究进展

随着全球人口的不断增加,工业化、城市化以及农业现代化的快速推进,湖泊富营养化问题已日益成为全球性的水环境污染问题。近年来,我国经济发展提速,资源利用强度加大,导致湖泊氮、磷营养盐严重富集,某些湖泊生态系统结构遭受破坏,功能紊乱,一些区域的湖泊蓝藻水华频繁爆发,湖泊富营养化呈现迅猛发展的趋势,并对区域经济发展与生产、生活用水保障带来挑战。尽管为了防控湖泊富营养化,我国各级政府投入了大量人力与物力,但在一些湖泊富营养化频繁区,一些防治与控制措施还没有收到理想而满意的效果。文章在综述国内外湖泊富营养化防治与控制策略研究的基础上,阐述了我国在富营养化研究方面存在的主要问题,提出了我国湖泊富营养化分区、分类控制的新思路。     

Evaluation of dust activity and climate effects in North China

TOMS/Al data with nearly 20 years are utilized in the paper to evaluate dust activities in North China. Combined with simultaneous NCEP reanalysis climate data, climate effects on dust activities are assessed. The results showed that the whole North China suffers impact by dust aerosols, with three centers standing out in TOMS/Al spring average map that are western three basins, which are characterized by lower annual precipitation and elevation. Gobi deserts in Mongolia Plateau do not attain higher TOMS/AI value due to cloud contamination and relative higher elevation. Spring is the season with the highest TOMS dust aerosol index; within the western three basins, high dust aerosol index appears in both spring and summer, especially in Tarim Basin. Wind speed in spring and precipitation in previous rainy season play important roles in controlling dust activities, higher wind speed and less precipitation than the normal are in favor of dust activities in spring. Temperature in spring and previous winter also affect dust activity to a certain extent, but with contrary spatial distribution. Temperature in winter exert effect principally in west part, contrarily, temperature effect in spring is mainly shown in east part. Both of them have negative correlation with dust activity.     

Long-term joint e ect of nutrients and temperature increase on algal growth in Lake Taihu, China

To study how global warming and eutrophication a ect water ecosystems, a multiplicative growth Monod model, modified by incorporating the Arrhenius equation, was applied to Lake Taihu to quantitatively study the relationships between algal biomass and both nutrients and temperature using long-term data. To qualitatively assess which factor was a limitation of the improved model, temperature variables were calculated using annual mean air temperature (AT), water temperature (WT), and their average temperature (ST), while substrate variables were calculated using annual mean total nitrogen (TN), total phosphorus (TP), and their weighted aggregate (R), respectively. The nine fitted curves showed that TN and AT were two important factors influencing algal growth; AT limited growth as algal photosynthesis is mainly carried out near the water surface; N leakage of phytoplankton and internal phosphorus load from sediment explains why TN was the best predictor of peak biomass using the Monod model. The fitted results suggest that annual mean algal biomass increased by 0.145 times when annual mean AT increased by 1.0°C. Results also showed that the more eutrophic the lake, the greater the e ect AT had on algal growth. Subsequently, the long-term joint e ect of annual temperature increase and eutrophication to water ecosystems can be quantitatively assessed and predicted.     

Long-term joint effect of nutrients and temperature increase on algal growth in Lake Taihu, China

To study how global warming and eutrophication affect water ecosystems, a multiplicative growth Monod model, modified by incorporating the Arrhenius equation, was applied to Lake Taihu to quantitatively study the relationships between algal biomass and both nutrients and temperature using long-term data. To qualitatively assess which factor was a limitation of the improved model, temperature variables were calculated using annual mean air temperature (AT), water temperature (WT), and their average temperature (ST), while substrate variables were calculated using annual mean total nitrogen (TN), total phosphorus (TP), and their weighted aggregate (R), respectively. The nine fitted curves showed that TN and AT were two important factors influencing algal growth; AT limited growth as algal photosynthesis is mainly carried out near the water surface; N leakage of phytoplankton and internal phosphorus load from sediment explains why TN was the best predictor of peak biomass using the Monod model. The fitted results suggest that annual mean algal biomass increased by 0.145 times when annual mean AT increased by 1.0℃. Results also showed that the more eutrophic the lake, the greater the effect AT had on algal growth. Subsequently, the long-term joint effect of annual temperature increase and eutrophication to water ecosystems can be quantitatively assessed and predicted.     

Response of community composition and biomass of submerged macrophytes to variation in underwater light, wind and trophic status in a large eutrophic shallow lake

Light climate is of key importance for the growth, community composition of submerged macrophytes in lakes and, they, in turn, are affected by lake depth and the degree of eutrophication. To test the relationships between submerged macrophyte presence and the ratio of Secchi disk depth (SDD) to water depth, i.e. SDD/depth, nutrients and wind, we conducted an extensive sampling campaign in a macrophyte-dominated area of the eastern region (n = 36) in 2016 in Lake Taihu, China, and combined the data gathered with results from extensive physico-chemical monitoring data from the entire lake. We confirmed that SDD/Depth is the primary factor controlling the community composition of macrophytes and showed that plant abundance increased with increasing SDD/Depth ratio (p < 0.01), but that only SDD/Depth > 0.4 ensured growth of submerged macrophytes. Total phosphorus and total nitrogen also influenced the growth and community composition of macrophytes (p < 0.01), while Chla was an indirectly affecting factor by reducing underwater light penetration. Wave height significantly influenced plant abundance (p < 0.01), whereas it had little effect on the biomass (p > 0.05). The key to restore the macrophyte beds in the lake is to reduce the nutrient loading. A decrease of the water level may contribute as well in the shallow bays but will not bring plants back in the main part of the lake. As the tolerance of shade and nutrients varied among the species studied, this should be taken into account in the restoration of lakes by addition of plants.     

西藏中部巴木错湖泊面积变化及其原因分析

受气候变化影响,西藏中部内陆湖泊在最近10 a来出现了水位上涨、湖面扩大等情况。采用遥感技术及统计学方法分析了西藏中部巴木错湖泊面积年内、年际变化及其原因。结果表明:①湖泊周边班戈站的年降水量、年平均气温、年平均地温以及年平均相对湿度等呈现增加趋势,年平均风速显现下降趋势;②2009年的面积在2月、5月和8月出现了三个"峰值",主要与湖面封冻、气温升高及降水增加等有关,年际变化呈逐步增加趋势;③经线性相关、多元回归等分析发现,年内变化受各月面降水量AP、蒸发量E和气温T的影响,合计贡献率为90.0%,排序为AP>E>T;年际变化受年平均风速SWS、7月降水量P7、平均地温ST和气温T的影响,合计贡献率为65.2%,排序为SWS>P7>ST>T。