Assessing the Impact of Leather Industry to Water Quality in the Aojing Watershed in Zhejiang Province, China

The development of the leather industry in the Aojiang watershed of Zhejiang province increased the release of waste water. In the waste water, ammonium nitrogen (NH⁺ ₄-N) and germanium (Ge) are the main pollutants. In recent years, literature has documented that the intake of high concentrations of NH⁺ ₄-N and Ge harms human health and biological species. This paper focuses on assessing the trends of NH⁺ ₄-N and Ge concentrations in the released waste water in Aojiang watershed and on understanding their relationships with the released waste water using regression and correlation statistics. The paper also utilizes the integrated pollution index to evaluate the water quality in the watershed. Preliminary results show that, from 1992 to 1998, the concentrations of NH⁺ ₄-N and total Ge increased 13 and 14 times, respectively, and they decreased somewhat after 1998. The concentrations of NH⁺ ₄-N and total Ge are positively correlated to the amount of released waste water. These concentrations of NH⁺ ₄-N and Ge, respectively, exceed 12 and 3 times, of the water standards. The water quality in the watershed degraded from Type III in 1992 to over Type V in 2003 when they were compared with the national water quality standards. It appeared that the pollution had positive correlation with leather industry production. The degraded water has no doubt affected human health and the ecosystem health. These results can provide scientific information for the local government to reasonably adjust the industry structure and reduce the pollution to protect the environment.     

漓江流域红壤侵蚀区植被演替与复合农林试验

漓江季节性的干旱和洪涝并存成为地方政府、有关专家和旅游行业密切关注的环境问题,漓江流域的环境建设尤其是上游森林植被恢复,成为生态治理重点内容。漓江上游红壤区植被类型主要包括针叶林、阔叶林、竹林、灌丛和草丛,植被的水分特征差异较大,植被的生态调节、水源涵养功能各异。在漓江上游红壤区开展4种模式的植被恢复和复合农林试验示范,3年的试验表明,乡土常绿阔叶树适应性强、有效保持水土,果林经济效益显著、但生态功能较差,木本药材林具有较好的生态功能和潜在的经济效益。通过调查和试验示范,提出亚热带红壤退化山地农林经营的植物种类和复合模式,对漓江流域水资源调控和水土流失治理提出建议和对策。     

基于GIS与QuickBird影像的小流域土壤侵蚀定量评价

基于GIS技术和QuickBird遥感影像,采用修正的通用土壤流失方程RUSLE作为评价模型,计算了清水沟小流域土壤侵蚀量,并结合土壤侵蚀强度分级标准,生成流域土壤侵蚀强度等级图;利用GIS的叠置分析功能,定量分析了土壤侵蚀与坡度和土地利用之间的关系,并针对不同水保措施预测了水土保持治理效果.结果表明清水沟小流域土壤侵蚀模数为75.02 t·hm-2·a-1,属强度侵蚀区,年水土流失量2.6×104 t;流域64.5%的泥沙来自于占流域面积仅28%的极强度和剧烈侵蚀区域;经分析,流域土壤侵蚀模数与坡度呈显著正相关,不同土地利用类型的土壤侵蚀模数大小排序依次为难利用地＞建设用地＞坡耕地＞园地＞草地＞林地;退耕还林是降低土壤侵蚀强度与减少水土流失量的主要途径.     

Comparison of a Subjective and a Physical Approach for Identification of Priority Areas for Soil and Water Management in a Watershed – A Case Study of Nagwan Watershed in Hazaribagh District of Jharkhand, India

The present investigation was an attempt to compare the within-watershed prioritization capabilities of a physical model based SDSS with the SYI and RPI model based subjective-SDSS, conventionally devised for between-watershed prioritizations, by All India Soil Survey and Land Use Planning Division of Ministry of Agriculture, Government of India. Application of these two approaches on a test watershed situated in Damodar-Barakar catchment in India, the second most seriously eroded area in the world, demonstrated that the proposed physical model based SDSS was capable of realistically and logically mimicking the sub-watershed-scaled water and soil losses thereby suggesting its immense application potential for priority area identification within the test watershed. In contrast to the proposed physical method, the subjective approaches, which assigned totally reverse priorities to about 67–93% of the test-sub-watersheds, were observed to be incapable of realistically assessing the impact of topography and varied land use and soil types in the test watershed on their sub-watershed scaled run-off and soil loss generating potential. Besides, the physical approach could be used for assessing the annual dynamics of the total water and sediment yields, under prevailing resource management systems in the test watershed with good to moderately good correlation coefficients of 0.83 and 0.65; model efficiency coefficients of 0.54 and 0.70; mean relative errors of –4.28% and –17.97% and root mean square prediction errors of 71.8 mm and 9.63 t/ha, respectively.     

伊犁低山丘陵区小流域水土保持措施优化配置研究

在调查分析伊犁低山丘陵区水土流失特点的基础上,研究了该区小流域水土保持措施的空间配置。结果表明：伊犁低山丘陵区水土流失主要表现为以水力侵蚀为主的多种土壤侵蚀类型作用下的坡面侵蚀和沟道侵蚀。针对其水土流失特点,伊犁低山丘陵区小流域水土保持措施优化配置为：以生态修复为主,上游地区封禁保护;中游地区种植水保林和经济林带,建立生态缓冲带;下游水平沟种草。通过综合治理开展水土保持生态环境建设,至2012年底,伊犁低山丘陵区治理程度达到77．33％,林草覆盖率48％,改善了当地生态环境。     

草皮缓冲带对洱海流域面源污染的削减效果

在前期植物调查和资料调研的基础上,构建了以百慕大、结缕草、混播草草皮为陆生植物的缓冲带,以洱海流域面源污染水样为这些植被缓冲带的进水,进行削减效果的现场中试实验。结果表明,裸露地表对径流SS几乎没有削减效果,而草皮缓冲带能有效截留径流SS,去除率大小顺序为混播草缓冲带> 结缕草缓冲带> 百慕大缓冲带;草皮缓冲带渗流水中的TN、TP的去除率均在60%以上,而径流水中TN、TP的去除率在40%以上;总体而言,草皮缓冲带对面源污染的削减效果沿程增强,且前段去除效果较强,后段去除效果减弱,其中混播草缓冲带的削减效果最好,百慕大缓冲带的削减效果相对较差;通过计算,当SS去除率为70%时,混播草缓冲带的最佳宽度仅为13.4 m,比百慕大缓冲带缩短了5.2 m。     

Watershed-based riverine discharge loads and emission factor of perfluorinated surfactants in Korean peninsula

Long-range transport of and exposure to perfluorinated substances (PFSs) strongly depend on their emission mode. In the present study, watershed-based riverine discharge loads and emission factors are estimated for perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorohexylsulfonate (PFHxS), and perfluorooctylsulfonate (PFOS) by using spatially distributed data of chemical concentrations together with water flows and a geographic information system (GIS). Average per capita emissions (emission factor, μg capita⁻¹ d⁻¹) are 75 for PFOA, 36 for PFNA, 17 for PFHxS, and 43 for PFOS, which are several times lower than the estimates for Japan and the European continent. A relatively uniform distribution is observed for PFHxS and PFOS emission factors, while elevated values of PFOA and PFNA predominate in one of eight river basins. This may indicate the leading contribution of diffusive sources (e.g. nonpoint source) for PFHxS and PFOS versus the presence of localized point sources for PFOA and PFNA. The lower-upper bound of total riverine loads discharged annually from the Korean peninsula are in the range of 0.53-1.3 tons for PFOA, 0.09-0.60 tons for PFNA, 0.07-0.29 tons for PFHxS, and 0.19-0.73 tons for PFOS, accounting for <1% of global annual emissions. Furthermore, these riverine discharge loads are significantly greater than the discharge loads from a wastewater treatment plant, indicating the necessity of further study of nonpoint sources.     

基于流域管理的土地利用研究与应用

研究流域中的土地利用,目的是通过分析不同的土地利用方式对流域生态环境的影响,探讨流域中合理的土地利用方式,从而有效地指导流域管理的实施。本文从研究的主要内容、方法与技术手段以及土地利用在流域管理中的具体应用等方面分别加以阐述,探讨了土地利用研究在流域管理中的积极意义。在总结国内外流域内土地利用管理经验的基础上,提出了土地利用规划必须做到经济效益、生态效益与社会效益三者统一,流域土地利用规划可以在遵循基本步骤的原则下,大胆借鉴外国成功经验,结合我国流域的特点,切实地做到流域资源的可持续发展。     

洱海常见沉水植物磷含量的种间差异及季节性变化特征

P是湖泊生态系统中很重要的生命元素,水生植物对于湖泊中P的生物化学循环至关重要. 通过分析不同季节下洱海7种常见的沉水植物地上部分w(P),研究了洱海常见沉水植物地上部分w(P)的种间差异及季节性变化特征. 结果表明:洱海沉水植物地上部分w(P)总体呈正态分布,平均值为2.64 mg/g,范围为0.90~6.79 mg/g. 沉水植物地上部分w(P)的种间差异和季节差异显著,其中7种沉水植物地上部分w(P)平均值为苦草(3.32 mg/g)>轮叶黑藻(2.88 mg/g)>金鱼藻(2.72 mg/g)>微齿眼子菜(2.53 mg/g)>穗花狐尾藻(2.39 mg/g)>篦齿眼子菜(2.34 mg/g)>马来眼子菜(2.27 mg/g);季节间表现为春季(3.46 mg/g)>夏季(3.05 mg/g)>冬季(2.20 mg/g)>秋季(1.98 mg/g). 环境中w(P)、叶与茎生物量比值和生活史特征可能是决定植物地上部分w(P)的重要因素. 此外,由于环境中有效P含量较低,洱海沉水植物地上部分w(P)低于长江中下游湖泊.      

高原湖泊典型农业小流域氮、磷排放特征研究——以凤羽河小流域为例

通过对凤羽河小流域出水口断面进行定位连续监测,计算流域出水量和氮磷排放量,解析了流域氮磷排放量的时间变化特征,以期为小流域氮磷排放量计算、农业管理措施调控、削减流域氮磷排放量提供科学依据.结果表明,凤羽河小流域年度水流量为0.99亿m3,7—9月雨季水流量占全年的43.70%.小流域总氮(TN)的年排放量为139.8 t,可溶性总氮(DTN)是氮的主要排放形式,占TN的71.16%,颗粒态氮(PN)占TN的28.84%.小流域总磷(TP)的年排放量为27.7 t,颗粒态磷(PP)是磷的主要排放形式,占TP的76.47%,可溶性总磷(DTP)占TP的23.53%.7—9月雨季氮磷排放量占全年总量的比例分别为55.33%和77.81%.降雨是影响流域径流过程的重要因素,同时,流域内农业管理措施对径流量和氮磷排放具有较大影响.