水生植被恢复对东莞生态工业园区水质改善的影响研究

为促进工业园区水生态环境建设,以东莞生态产业园区水生态系统恢复为研究对象,研究了其建园初期水生植被恢复对重污染水体水质修复的影响,并应用因子分析法对水质与主要生态因子之间的相互关系进行了研究,探讨了水体修复效果与水生植被覆盖率的关系.结果表明：水生植被恢复可使园区生态岛群与月湖主要水质指标（总氮、总磷、氨氮和高锰酸盐指数）从建设初期（2011 年5 月）的劣V 类改善为II-III 类（2012 年）,透明度提高约1 倍,而下沙与大圳埔湿地也从劣V类（2011 年5 月）改善为IV-V 类（2012 年）,透明度提高约50%.10 项水质指标的因子分析表明,园区水质成因可归为综合营养因子（氨氮、高锰酸盐指数、叶绿素、透明度、总磷和总氮）、温度因子（温度、电导率、硝态氮）和光合作用因子（溶解氧和pH）,其中主导指标为氨氮、高锰酸盐指数、叶绿素a、透明度和总磷等.三类因子分别客观反映了修复水体的水质变化特点：氮磷及有机物的含量越低则水体透明度越高,水质越优;温度升高有利于水质改善;藻类光合作用减弱,则水质变优.生态岛群、月湖、下沙、大圳埔湿地的水生植被覆盖率分别为43.8%、22%、4.3%、9.1%,此差异与水质修复效果相关.回归分析显示水质指标与水生植被覆盖率呈极显著的二项式关系（p〈0.01）,根据拟合方程计算得出污染物浓度最低、透明度最高、综合水质最优时的水生植被覆盖率变动范围为30%~35%.因此,生态岛群与月湖的水质改善效果优于大圳埔湿地,大圳埔湿地则又优于下沙湿地;下沙与大圳埔湿地可通过适当增加浮、挺水植物的面积比例,提高水体修复能力.文中所得最适水生植被覆盖率范围可为华南地区工业园区水生态初期修复提供一定的参考价值.     

Implementation of riverside parks in the city of São Paulo – progress and constraints

The environmental degradation of urban rivers and streams in large cities has led to the development of a variety of public policies. In the city of São Paulo, Brazil, a policy for recovering watercourses and valley floors has been developed with the implementation of riverside parks. This represents a new paradigm for the city in terms of its relationship with rivers and streams. This paper presents the results of an exploratory study, which aimed to analyse riverside parks in the city of São Paulo during the last decade. The study analysed the main management difficulties in relation to these types of urban park during their post-implementation stage, assessing their performance in relation to their social and environmental functions. It addressed issues such as the state of the site before and after the implementation of the riverside park, levels of user satisfaction in relation to the state of the watercourse, sports and leisure facilities, green space, security and the way the park is used. The study showed that riverside parks are recognised as elements that improve the quality of public spaces, socially legitimised as public policies.     

山地风电工程建设中水土保持及植被恢复的设计方案探究

分析了云南风电建设的现状,提出了生态环保示范性山地风电工程的概念和原则,并以华能南华云台山风电工程为例,从建设前、中的水土保持措施及后期植被恢复方案对道路、弃渣场、风机平台等区域进行探究,并对工程建设的生态、经济效益进行了预测.研究指出,生态环保示范性山地风电工程的建设既不同于荒山造林或更新造林,也不同于园林绿化.既要考虑生态恢复和水土保持功能,又要考虑植被恢复效果、环境美化和降低成本.因而在前期、建设过程中要做好勘测,因地制宜多方评审,优化方案.能够让生态系统不经过人为的干预,还原、融入到被破坏前的环境当中去,将生态恢复和一定的经济效益、环境美化结合起来,实现改善生态、生活环境,促进人与自然和谐发展的最终目标.     

Design of Experimental Streams for Simulating Headwater Stream Restoration1

Huang, Jung-Chen, William J. Mitsch, and Andrew D. Ward, 2010. Design of Experimental Streams for Simulating Headwater Stream Restoration. Journal of the American Water Resources Association (JAWRA) 1-15. DOI: 10.1111/j.1752-1688.2010.00467.x Abstract: Headwater streams flowing through agricultural fields in the midwestern United States have been extensively modified to accommodate subsurface drainage systems, resulting in deepened, straightened, and widened streams. To restore these headwater streams, partial or total reconstruction of channels is frequently attempted. There are different approaches to reconstructing the channel, yet there is little evidence that indicates which promises more success and there has been no experimental work to evaluate these approaches. This study designs three experimental channels – two-stage, self-design, and straightened channels – on a human-created swale at the Olentangy River Wetland Research Park, Columbus, Ohio, for long-term evaluation of headwater stream evolution after restoration. The swale receives a continuous flow of pumped river water from upstream wetlands. Using streamflow and stage data for the past 12 years, a channel-forming discharge of 0.18 m³/s was estimated from bankfull discharge, effective discharge, and recurrence interval. These stream channels, after construction, will be monitored to evaluate physical, chemical, and biological responses to different channels over a decade-long experiment. We hypothesize that the three stream restoration designs will eventually evolve to a similar channel form but with different time periods for convergence. Monitoring the frequency and magnitude of changes over at least 10 years is needed to document the most stable restored channel form.     

原位生态修复技术在城市河道中的应用

以昆山市凌家浜河道作为原位生态修复的试验对象,综合运用水生植物修复技术、生物膜技术等,改善水质。结合水生动物,平衡水体内浮游生物种类结构和数量,促进降解和转移水体中有机物质,达到河道生态系统原位修复的目的。研究表明:在有部分外源污染的情况下,采用该技术修复河道,水质改善显著,水体透明度、COD、TP、TN、NHN、叶绿素a等主要水质指标达到或优于地表水质标准。     

哈尔滨市松江湿地保护现状及生态修复策略研究

松江湿地是中国面积最大的河流型城市湿地.然而,随着城市化进程加快,生态功能正在逐步退化.目前,从实地调研情况看,松花江哈尔滨段下游湿地保护较好;而上游湿地保护工作不到位,大量湿地丧失,生态系统退化严重;整体看来,松江湿地生态系统受人为干扰严重,湿地片段化、斑块化现象严重.针对这一现状,列出了湿地目前存在的问题并分析退化和受损的原因,同时,筛选出了适合松江湿地的修复技术及生态恢复方案.     

喀斯特地区植被恢复下土壤活性有机碳与碳库管理指数的演变特征

植被恢复通过改变碳输入和转化速率,影响陆地生态系统的碳循环.为探明喀斯特地区植被恢复过程中土壤活性有机碳组分与碳库管理指数的演变特征,以喀斯特地区草地序列（5、10、15和20 a）、灌木序列（5、10、15和20 a）和园地序列（5、10和15 a）土壤为研究对象,以相邻农田为对照（CK）,分析了不同植被恢复年限对土壤有机碳（SOC）、易氧化有机碳（ROC₃₃₃、ROC₁₆₇和ROC₃₃,即能被333、167和33 mmol·L^-1 KMnO₄氧化的土壤活性有机碳）、微生物量碳（MBC）、溶解性有机碳（DOC）及碳库管理指数（CPMI）演变的影响.结果表明,与CK相比,0~40 cm土层草地、灌木和园地序列平均SOC含量分别增加了70.77%、114.40%和50.17%.在0~20 cm土层,随恢复年限增加,草地序列和园地序列的SOC含量呈先升后降势态,灌木序列呈先升后降再升势态,ROC₃₃₃、ROC₁₆₇和ROC₃₃与对应序列的SOC变化势态一致;在20~40 cm土层,各序列的ROC₃₃₃、ROC₁₆₇和ROC₃₃与对应序列的SOC的变化势态不一致.在0~40 cm土层,草地序列MBC含量呈先降后升再降势态,各土层MBC最大值均在G15;灌木序列在0~10 cm土层为先升后降再升势态,在10~40 cm土层为先升后降势态;园地序列在0~30 cm土层为先升后降势态,在30~40 cm土层为逐渐升高势态.3个序列K_os大致呈先降后升再降势态,L和LI与K_os相反;CPI呈先升后降势态;草地和园地序列的碳库管理指数（CPMI）呈先升后降势态,而灌木序列CPMI的则呈先升后降再升势态.SOC、ROC₃₃₃、ROC₁₆₇、ROC₃₃和MBC含量及K_os的年增长量大小为：灌木>草地>园地,DOC和CPMI的年增长量大小为：园地>草地>灌木.3个序列SOC及其组分含量均总体随土层增加而降低,具有明显的表聚性.冗余分析结果显示碱解氮（AN）是影响喀斯特地区植被恢复下土壤活性有机碳组分和土壤有机碳库的主要环境因子.综上,土壤活性有机碳组分和CPMI随植被恢复时间发生演变,不同植被恢复均能一定程度地提高喀斯特地区SOC及其组分含量,灌木恢复促进SOC的积累.     

长江上游生态退化及其恢复与重建

长江上游生态建设取得了显著成绩,20世纪90年代森林覆盖率和地表植被覆盖度较60～70年代有了显著的提高,如四川盆地浅丘区森林覆盖率,60年代只有5％左右,到90年代后期达22.7％。虽然地表植被覆盖有了显著改善,但是生态退化问题仍比较严重,突出地表现在如下几方面:①森林生态系统的空间结构不合理,群落层片结构简单,人工林生态系统的林种、树种组成单一,低山丘陵区针叶化倾向日趋明显,其林下枯枝落叶层缺失,森林土壤层很薄,一般只有30～40cm,土壤最大持水能力一般为300～500m~3/hm~2,而该地区原始森林土壤可达2000～2500m~3/hm~2。②草地生态系统退化面积在扩大,如长江上游源头地区草地破坏引起的土地荒漠化面积达195万hm~2。③农田生态系统退化主要分布于生产与生态功能均不高的坡耕地,多数坡耕地水土流失比较严重,土壤侵蚀模数一般达2500～5000t/km~2·a,坡耕地耕作层浅薄,蓄水保水功能很弱。根据本区主要生态系统类型的退化现状与特点,在生态学理论的指导下,提出退化生态系统的恢复、重建与改建的对策和途径,为长江上游生态屏障的构建提供新的思路。     

Bankfull Regional Curves for the Inner and Outer Bluegrass Regions of Kentucky1

Brockman, Ruth R., Carmen T. Agouridis, Stephen R. Workman, Lindell E. Ormsbee, and Alex W. Fogle, 2012. Bankfull Regional Curves for the Inner and Outer Bluegrass Regions of Kentucky. Journal of the American Water Resources Association (JAWRA) 48(2): 391‐406. DOI: 10.1111/j.1752‐1688.2011.00621.x Abstract: Bankfull regional curves that relate channel dimensions and discharge to watershed drainage area are useful tools for assisting in the correct identification of bankfull elevation and in stream restoration and reconstruction. This study assessed 28 stable streams located in two physiographic regions of Kentucky: the Inner Bluegrass and the Outer Bluegrass. Bankfull channel dimensions, discharge, and return period as well as average channel slope, median bed material size, sinuosity, Rosgen stream classification, and percent impervious area were determined. Significant relationships were found between drainage area and the bankfull characteristics of cross‐sectional area, width, mean depth, and discharge for both the Inner Bluegrass and Outer Bluegrass regions (α = 0.05). It was also found that the percent impervious area in a watershed had minimal effect on bankfull dimensions, which is attributed to the well‐vegetated nature of the streambanks, cohesive streambank materials, and bedrock control. No significant differences between any of the Inner Bluegrass and Outer Bluegrass regional curves were found (α = 0.05). Comparisons were made between the Inner Bluegrass and Outer Bluegrass curves and others developed in karst‐influenced areas in the Eastern United States. Although few significant differences were found between the regional curves for bankfull discharge and width, a number of the curves differed with regards to bankfull cross‐sectional area and mean depth.     

矿山恢复过程及前期恢复时限分析

目前矿山生态环境防治原则“谁开发谁保护,谁污染谁治理,谁破坏谁恢复”对矿山恢复到特定程度还没有明确的时间要求。矿山恢复可分为前期和后期两个阶段,前期恢复以水土保持为目的,后期恢复以建立稳定的生态系统为目的。草本植被在前期恢复中具有显著的水土保持功效。不同区域的草本植被恢复到特定盖度有明显的时间分异,所需时间与区域NPP(植被净第一性生产力)值呈负相关。据估计,草本植被恢复到70%的盖度,热带林区大致需要5~9个月,亚热带常绿阔叶林带需要9~15个月,温带林区需要15~24个月,寒带针叶林带和温带草原则需要超过两年的时间。建立的盖度-T(时间)-NPP曲线,结合区域植被有效盖度,为矿山前期恢复的时限制定提供依据。