New Normal Control of Agricultural Non-point Source Pollution in the Dianchi Lake Basin

Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed.

Pollution Control Programs of Large-Scale Livestock and Poultry Farms in the Dianchi Lake Basin

With the enlarging scale and intensifying production of livestock and poultry breeding, the environment pollution becomes increasingly prominent in the Dianchi Lake Basin since 1990s. According to the survey of ＂The First National Census of Pollution Sources＂, occurrence and discharge of pollutants in large-scale livestock and poultry farms in this region were first understood. The pollution characteristics of large-scale live- stock and poultry breeding were also analyzed deeply. On this basis, the significance of pollution control programs for environment protection was investigated from aspects of pollution control policy, technology management and publicity.

GIS Based Evaluation System for Ecological Constraints of Dianchi Lake Basin

With the advance of urbanization process and rapid growth of urban population,the construction land scale in Dianchi Lake basin increases at a sharp speed.Due to lack of reasonable scale control and space optimization,many areas have the problem of blind growth in construction land.On the one hand,it results in deterioration of regional ecological environment.On the other,it poses hidden danger for sustainable land use in the basin.Therefore,in order to coordination of regional land use and ecological environment construction,this paper on the basis of the existing various zoning method,the natural ecological conditions and resources environment as the constraint conditions of regional ecological balance,puts forward the Dianchi lake watershed ecological constraint type classification method based on GIS,and discusses the evaluation unit division,index selection and handling technical issues.Through evaluating ecological constraints of Dianchi Lake basin,this study divided Dianchi Lake basin into extremely high,higher,high,medium and low ecological constraint zones.Finally,it came up with guiding and regulating measures for land use of each type of ecological constraint,in the hope of providing scientific basis for optimum allocation of land resources in Dianchi Lake basin.

Study on Control Scheme for Nonpoint Source Pollution in Dahe Reservoir Water Source Protection Area of Dianchi Lake Basin

[ Objective] The research aimed to study control scheme for nonpoint source pollution in Dahe Reservoir water source protection area of Dianchi Lake basin.[ Method] On the basis of the SPOT5 satellite remote sensing imagery in 2010 and field investigation of GPS record, ecological design for nonpoint source pollution control in Dahe Reservoir water source protection area of Dianchi Lake basin was conducted. Then, the effects of optimization measures were evaluated by the reductions of N and P outputs on different land-use types. E Resultl Control functions of the water source protection area on soil erosion and the emissions of N, P and other pollutants would be promoted after optimization. The optimization meas- ures had a significant effect for prevention and control of the non-point source pollution in the water source protection area. [ Conclusion] The re- search provided scientific basis for promoting ecological construction of the small green basin in Dahe Reservoir water source protection area of Di- anchi Lake basin.

Dynamic evaluation of water resources carrying capacity of the Dianchi Lake Basin in 2005-2015,based on DSPERM framework model and simulated annealing-projection pursuit model

With the intensi fed impact of human activities,most lakes have been severely disturbed and the lake ecosystem has been seriously damaged,which exerted a great impact on the living envi-ronment of human beings in the lake basins.The health of the lake ecosystem has gradually become one of the hot issues in recent years.In this study,the water resources carrying capacity(WRCC)was used to reveal the chain rel ationship between human activities and water environ-ment in the economic dewelopment of the Dianchi Lake Basin in Kunming City of China during 2005-2015.Specifically,we chose 25 ewaluation indicators related to the water environment and socialeconomic activities,classified them into six subsystems,Le,the driwing force subsystem(D),the water resources si tuation and consumption subsystem(S),the water resources pressure subsystem(P),the water environmental situation subsystem(E),the response subsystem(R),and the management subsystem(M),and built a comprehensive assessment system-DSPERM frame-work model.Si mulated annealing-projection pursuit model which reflects the structure or feature of high-dimensional data was adopted to calculate the WRCC of the Dianchi Lake Basin during 2005-2015 by weighting each evaluation indicator and each subsystem of the DSPERM frame work model.The resuls show that the WRCC of the Dlanchi Lake Basin was in level II(medium carying capacity)from 2005 to 2012.Since 2013,the WRCC has been at level II(strong carying capacity),and from 2005 to 2015,it showed a gradual upward trend.The evaluation indicators of each subsystem varied greatly and exhibited different development trends.The indicators of the water resources pressure subsystem had the greatest impact on the WRCC,followed by the in-dicators of the water environmental si tuation subsystem and the water resources situation and consumption subsystem.We recommend that the DSPERM framework model and the simulated anneal ing-projection pursuit model constructed in this work can be used to analyze the dynamic changes of the WRCC over the years.They have the advantages of practicability and feasibilty,and can provide the basis for the scienti fic decision-making and comprehensive management of regional water environment planning.

Advances in History, Current Situation and Control of Agricultural Non-point Source Pollution in the Dianchi Lake Basin

Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures of agricultural non-point source pollution in the basin were summarized to provide theoretical and technical support for the thorough improvement of present situation of water pollution in the basin.

Nitrogen forms and pollution load of Dianchi Lake inflow river runoff in rainy season

With the control of point source pollution in Dianchi Lake basin, and the expansion of Kunming city, non-point source pollution has become the main source pollution of urban water environment and Dianchi Lake. To reveal the nitrogen pollution characteristics in watershed, this research selected key monitoring points and sections at Baoxiang river basin in rainy season which is the peak transported time of non-point source pollution, the nitrogen and hydrological indicators are monitored systematically. The different forms of nitrogen are analyzed, the pollution load of nitrogen are calculated and studied at cardinal sections; combined with the literature data, we compared the water nitrogen characteristics of Dianchi basin and Taihu basin, the main results are as follows:(1) In summer, water nitrogen form of Baoxiang river in the Caohe area is dominated by nitrate nitrogen, while in other areas it is dominated by ammonia nitrogen which is accounted for 31%-50% of total nitrogen;(2) The water pollution loads of Baoxiang river tended to increase from upstream to downstream, from June to August the total nitrogen pollution mainly comes from urban areas and the pollution load is 166.408 t;(3) In Dianchi Lake watershed and Taihu Lake watershed nitrogen concentration of inflow river is higher than that of the lake, nitrate nitrogen concentration between inflow river and lake shows a little difference, while ammonia nitrogen concentration of inflow river is higher than that of the lake. The results can provide the theoretical basis for nonpoint source pollution control and urban water environment planning and improvement in Dianchi Lake Basin.

滇池流域生态系统完整性变化及其驱动机理实证研究

滇池流域是长江水源的重要涵养地和我国西南的生态安全屏障,其生态系统完整性变化是整个流域生态系统质量和稳定性的重要体现,对生态系统保护和修复具有重要指导意义。通过ArcGIS空间分析、地理探测器模型和皮尔逊相关分析等方法,基于生态系统结构、功能和弹性三方面构建综合指数,评估2000—2020年滇池流域生态系统完整性时空变化,分析生态系统完整性演变的驱动因子及其作用机理。结果表明:(1)滇池流域生态系统完整性先下降后上升,但整体有所降低,其中结构完整性明显降低、生态系统弹性显著减弱。(2)生态系统完整性在空间上呈中部低四周高的分布格局,完整性高的区域分布在城市外围的山体,靠近滇池北部的中心城区则较低;全流域36.24%的区域完整性降低、35.31%的区域升高。(3)生态系统完整性的时空变化受自然条件和人文社会经济等多种因素的共同影响,高程、气温和土地利用变化是主导因子,完整性与高程呈正相关,与气温呈负相关,但土地利用变化的影响具有双重性。研究结果可为流域生态系统完整性评估提供新思路,同时为滇池流域生态系统的管护提供科学依据。

基于风险-质量的高原湖泊流域生态分区构建--以滇池流域为例

随着人类足迹不断延伸,高原湖泊流域人地系统三生空间冲突显著。以滇池流域为例,顾及流域三生空间冲突风险,基于三生空间景观格局和生态环境质量的变化,尝试引入四象限模型,结合热点分析,划分风险-质量综合生态环境分区。结果表明:(1)滇池流域三生空间冲突风险类型以较强为主,冲突曲线指数呈现倒“U”型,较强冲突比重不断下降。三生空间类型转换明显,生活空间共增长了312.23km^(2),主要是由于高原湖泊流域的快速城镇化使得生活空间大量挤占了生产和生态空间。(2)滇池流域生态环境质量总体呈现下降趋势,空间上以滇池为中心呈现高-低-高的分布特征。较高质量和高质量区面积减少了136.66km^(2);低质量区和较低质量区由699.65km^(2)上升到930.51km^(2),约占流域总面积的1/3。(3)基于三生空间冲突风险和生态环境质量两个维度将生态分区分为综合生态环境优质、良好、一般、劣质四类,四类区的空间分布连续性相对较好,尤以劣质区面积连续扩展的态势最为典型。针对不同生态分区提出差异化管理措施,为流域人地协调发展提供实践指导。

滇池流域农业绿色发展水平综合评价及影响因素研究

推动滇池流域农业绿色高质量发展,对促进滇池治理和生态环境保护具有重要的现实意义。本文以滇池流域的7个县区为研究对象,从资源节约、环境友好和高效发展三个层面,结合滇池流域农业绿色发展的区域性特征,构建了15个适合滇池流域农业绿色发展的评价指标体系,运用熵值法对滇池流域农业绿色发展水平进行综合评价,运用灰色关联分析法对滇池流域农业绿色发展影响因素进行排序。结果表明:(1)2015—2020年,滇池流域农业绿色发展水平得到提升,但发展并不稳定和不平衡;(2)环境友好发展水平相对较高,但是资源节约和高效发展依旧是短板,同时高效发展增速最慢;(3)影响滇池流域农业绿色发展水平最大的因素是环境友好,高效发展影响适中,资源节约影响最小;(4)具体指标中,影响最大的因素是农业服务业贡献率、农村人均可支配收入、农药施用强度、湖泊营养状态指数和森林覆盖率。

滇池环湖截污体系优选截留率及其影响因素研究

农村农业非点源污染是滇池污染负荷的主要来源之一,环湖截污治污体系对农村农业污水的截留具有重要意义。为实现对该体系的自动化控制,有效支撑智能化控制平台的高效运行,本研究在前期通过对比分析,确定截污治污体系截流井采用基于总磷(TP)浓度阈值控制模式对农村农业非点源污染物负荷截留效果最好的基础上,针对环湖截污治污体系现状条件下,采用TP浓度阈值控制模式对应的优选截留率进行研究,探讨了重现期和雨峰系数的影响,并就选择性截留后枯、平和丰水年农业农村非点源污染负荷的入湖系数进行计算。结果表明,(1)当干渠发生溢流时,存在优选TP浓度阈值,当截留TP浓度大于等于该阈值的径流时,可以使溢流进入滇池的污染物负荷最小,此时截留径流量与总径流量的比值即为优选截留率。(2)随重现期的增大,TP浓度阈值的设定值整体呈减小趋势,所截留的污染物平均浓度减小,优选截留率减小。(3)随雨峰系数增大,TP浓度阈值的设定值增大,优选截留率变化不大。(4)考虑基于TP浓度阈值控制模式的环湖截污系统截留作用后,滇池农业农村非点源污染负荷的入湖系数:枯、平、丰水年COD分别为0.09、0.14、0.23;总氮分别为0.10、0.22、0.31;TP分别为0.07、0.12、0.19,均较不考虑环湖截污系统截留作用时显著降低。(5)采用TP浓度阈值控制模式,在枯、平及丰水年均可有效提升截污干渠末端水质净化厂的进水浓度,增强处理工艺的运行稳定性。

基于PCA-APCS-MLR模型的滇池流域地下水质量影响因素定量识别

近年来,随着人类活动的加剧,滇池流域地下水质量不断恶化.本研究在评价流域地下水质量及主要影响指标的基础上,利用主成分分析法(PCA)归纳主要影响水质的驱动因子,并结合绝对主成分得分-多元线性回归受体模型(APCS-MLR模型)进一步量化了人为和天然因素对流域内地下水质量的影响程度.结果表明:①滇池流域约78%的地下水超过GB/T 14848-2017《地下水质量标准》Ⅲ类水标准,其中主要超标指标为铝(Al)、锰(Mn)和总铁(TFe).②通过主成分分析(PCA)提取了5类影响水质的主成分因子,分别为水岩相互作用因子(24.27%)、生活污水漏排因子(17.09%)、农业活动污染因子(12.24%)、地质环境背景因子(10.26%)和工业活动污染因子(9.14%),方差累积贡献率为73.00%.③利用APCS-MLR模型进一步量化了各类人为和天然因素对流域内地下水质量影响的贡献,5项因子对特征指标的平均贡献率分别为45.15%、70.76%、45.54%、54.1%和44.59%.研究显示,人类活动对地下水的过度开采及工农业活动是导致区域地下水质量下降的主要因素.

高原湖泊流域建设用地坡谱演变研究--以滇池流域为例

高原湖泊流域因受自然地理条件限制较大,建设用地不可避免地出现“向湖”“爬坡”扩张现象,通过构建建设用地坡谱可有效揭示其时空演变规律。以滇池流域为例,基于2000—2020年土地利用数据和基于DEM转化的海拔数据,借助陡峭度、均匀度、上限坡度等方法分析了坡谱演化特征,提出了加权爬坡指数(WBCI)以定量表征建设用地爬坡程度,并结合海拔区间的视角探究了建设用地扩张的空间分异及演变规律。结果表明:①滇池流域建设用地扩张显著,呈现以滇池北岸主城区为主核心,东岸呈贡区、南岸晋宁区为次核心的建设用地分布格局;②建设用地垂直空间扩张呈现两阶段特征,即先平地扩张后爬坡扩张。2000—2015年为向湖、降海拔扩张阶段(WBCI<0);2015—2020为爬坡、升海拔扩张阶段(WBCI>0)。③建设用地坡谱演变与海拔变化在流域尺度具有一致性,即爬坡指数变化趋势与建设用地分布的平均海拔变化趋势高度一致。但在区县尺度,建设用地爬坡扩张与海拔爬升存在明显的空间差异性。研究为城镇空间二维扩展向三维扩展提供新的思考和视角,也可为城镇空间用地规划及其生态环境效应评估提供支撑借鉴。

对滇池流域山水林田湖草一体化保护和系统治理的思考

滇池是“九五”时期以来我国重点治理的“三河三湖”之一,经过30年治理,水质明显改善,水生态系统演变趋势向好。然而目前,滇池流域“山水林田湖草”系统治理格局还未完全形成,流域生态系统韧性不足,水环境质量正处于进一步改善的瓶颈期。为探索滇池治理的未来发展路径,本文系统总结了前期滇池治理历程与成效,诊断了存在的主要问题,分析了滇池流域自然—社会复合生态系统特征,提出了滇池流域山水林田湖草一体化保护和系统治理的思路、目标、空间布局和重点任务,以期为新时期滇池流域水生态环境保护提供指导,也为其他城市型重污染湖泊流域从水污染防治向水生态保护的转变提供借鉴。

滇池湖底塌陷漏水隐患研究的问题与建议

持滇池漏水隐患点急变临灾推论和漏水隐患不成立否定意见的双方都做了大量的分析论证工作,并发表和提交了研究成果。但以地球系统科学、水工环地质学和地球探测技术科学的理论、原理和地质勘查认识问题的程序和规范来衡量,均不同程度地存在着概念性、系统性、规范性的错误或不足,主要表现在地质学概念及术语不清、水文地质调查研究不足、湖盆形成及演化历史研究薄弱、水文地质勘探验证欠缺等,从而导致各方推断依据皆不够充分。对这些问题,文章逐一进行了深入的分析,并根据区域自然地理、地质、水工环地质等调查(勘查)研究程度及资料,结合实际工作经验,对今后的研究提出了规范地质学基本概念、开展湖底洼地钻探试验及监测、系统开展综合研究和野外查证的具体改进建议。明确指出滇池漏水隐患成立与否,关键在于湖底洼地发生岩溶塌陷的风险,必须实施钻探验证才能得出科学的定论。

滇池流域大气氮、磷干湿沉降通量及入湖贡献

为了探究滇池流域氮、磷干湿沉降对滇池水体外源输入营养盐的贡献率,于2021年收集了滇池流域六大功能区的雨水及降尘,测定大气沉降中不同形态氮、磷质量浓度,分析滇池流域氮、磷大气沉降分布特征,并估算氮、磷干湿沉降全年沉降通量及对滇池入湖负荷的贡献。结果表明:流域内全年大气总氮(TN)、总磷(TP)湿沉降通量分别为20.244~220.938、1.155~65.826 kg/km^(2),干沉降通量分别为44.275~481.120、4.255~111.840 kg/km^(2);工业生产和矿产开发功能区分别为流域氮、磷干湿沉降通量最高的区域。溶解性无机氮(DIN)和溶解性无机磷(DIP)是大气沉降中氮、磷的主要形态;流域内氮、磷大气沉降入湖负荷分别为1018.92、88.88 t,其中滇池湖面大气直接沉降负荷占流域入湖污染负荷总量的3.70%和2.35%,流域其他区域入湖系数换算下大气沉降入湖负荷在流域河流入湖负荷中的占比分别为8.69%和6.26%。流域氮、磷大气沉降已逐渐成为滇池外源污染物的重要来源之一,深入掌握其时空分布特征及入湖贡献率是进一步加强流域管理和减轻湖体外源污染物输入的重要前提。

滇池流域城镇区河流底栖动物群落结构及受干扰状况研究

研究城镇区域底栖动物群落结构特征及受干扰状况,对修复城市河流生态系统具有指示意义。以滇池流域为研究对象,基于2021年8月的底栖动物数据,采用优势度指数、生物多样性指数及丰度/生物量比较(ABC)曲线探究了底栖动物群落结构及受干扰状况。研究结果表明:①共鉴定出底栖动物39种,属于3门5纲,以节肢动物门为主,占物种总数的48.7%,水丝蚓属(Limnodrilus sp.)、摇蚊属(Chironomus sp.)等污染指示种为主要优势种。②多样性指数分析表明,流域生物多样性整体较低,Shannon-Weaver多样性指数、Margalef丰富度指数在各样点的差异较大,而Pielou均匀度指数各点差异较小。③ABC曲线分析表明,城镇区群落结构干扰程度总体为中度干扰并呈现出一定的空间差异,各河流按干扰程度可以划分为三类,一类为无干扰河流,占比25.0%;一类为轻度干扰河流,占比66.7%;一类为中度干扰,占比8.3%。④本研究结果可为滇池流域城镇区域河流的生态保护提供科学依据,下一步应结合相关环境数据,深入了解各环境类型与底栖动物群落结构的相关关系。

灰色系统理论在旱涝灾害预测中的应用

根据灰色系统理论和建模原理,选取滇池流域1955—2020年降水资料为原始数据,建立旱灾灰色预测GM(1,1)模型;采用牛栏江流域1954—2020年最大流量资料,建立洪灾预测模型;将两个模型的预测值分别与实际旱灾和洪灾发生时间进行对比分析,探讨在水文长期预报中灰色灾变理论的应用。利用模型对流域未来旱涝灾害出现时间进行预测,未来10年内,滇池流域在2026—2027年、2031—2032年存在旱灾风险;牛栏江流域则在2025—2026年、2031—2032年发生洪灾的可能性较大。

滇池流域水文生态系统服务权衡与协同时空异质性及其归因分析

城市化扩张影响流域水文生态系统服务供给,导致水文生态环境压力增加。明晰滇池流域水文生态系统服务权衡与协同关系及归因,对于滇池流域社会经济发展与生态可持续管理的双赢具有重要意义。基于InVEST模型估算了滇池流域2000、2010、2018年碳存储、氮输出、土壤保持和产水量4种水文生态系统服务,分析了水文生态系统服务时空格局变化,利用双变量Moran′s I指数分析了滇池流域水文生态系统服务间时空异质性,通过冗余分析和条件效应分析等方法识别水文生态系统服务归因。结果表明:(1)水文生态系统服务的高值分布与土地利用覆盖有密切关系。(2)水文生态系统服务空间变化主要体现在滇池周边人类活动干扰强烈的区域,表现为氮输出、土壤保持和产水量增加,碳存储减小。(3)水文生态系统服务权衡与协同关系变化明显。碳存储和土壤保持为协同;氮输出和产水量先呈协同后呈权衡;产水量、氮输出均与碳存储和土壤保持为权衡,前者空间变化不明显,后者协同范围扩大,权衡范围缩小。(4)水文生态系统服务主要受多个因素共同影响,主要包括:高程、耕地比例、林地比例、建设用地比例。研究结果可为研究区水文生态系统环境治理和土地利用优化配置提供科学依据和决策支持。

滇池流域土地利用变化对地下水水质的影响

土地利用变化影响着浅层地下水水质,以滇池流域为研究对象,综合运用遥感影像解译、马尔科夫转移矩阵和冗余分析,对近20年(2002~2020)滇池流域土地利用和浅层地下水质变化进行分析,揭示长时间尺度下土地利用变化对浅层地下水水质的影响.结果表明:2002和2020年滇池流域土地利用类型以草地、林地和耕地为主,分别占总面积20.91%和17.43%、43.21%和37.99%、22.11%和17.08%,2002~2020年间耕地向建筑用地和林地、林地向草地和耕地、草地向林地和建筑用地转移概率分别为22.59%和20.72%、13.16%和10.49%、26.30%和15.65%,耕地面积减少146km^(2),建筑用地面积增加279km^(2).2002~2020年滇池流域浅层地下水化学类型由HCO_(3)^(-)·SO_(4)^(2-)-Mg^(2+)型转变为HCO_(3)^(-)·SO_(4)^(2-)-Ca^(2+)型,浅层地下水水质从I、II类下降至IV、V类,整体水质恶化.草地和林地与TN、NO_(3)^(-)-N呈负相关,表现为“汇”效应;建筑用地与TN、NO_(3)^(-)-N呈显著正相关(P<0.05),表现为“源”效应.可见,滇池流域土地利用空间格局变化显著影响着流域浅层地下水水质,建筑用地和耕地是导致滇池流域浅层地下水水质恶化的主要影响因素,合理规划、利用滇池流域土地资源对改善地下水水质具有重要意义.