用Markov模型预测长江水质

由于长江水质的污染程度日益严重，为了说明治理长江对长江水质进行了简单的评价,保护长江迫在眉睫，首先，根据长江流域的17个观测站近两年多的水质检测数据统计，说明了近两年多来长江的防污治理工作有一定的效果。然后，根据1995~2004年长江流域水质的数据报告，考虑各类水之间的相互转化，构造了马尔柯夫(Markov)转移矩阵，建立了马尔柯夫预测模型，通过已有的观测数据验证了该模型的正确性及有效性。运用该马尔柯夫模型预测未来10年水质的变化趋势，即Ⅰ、Ⅱ、Ⅲ、Ⅳ类水逐年减少,而Ⅴ、劣Ⅴ类水逐年增加。到2014年，长江的第Ⅰ类水只有0.4 059%，劣Ⅴ类水达到26.2 714%，不可饮用水（即第Ⅳ,Ⅴ,劣Ⅴ类水）将达到47.468%，为此应采取更加有效的治理措施，控制长江水质的恶化。最后，通过计算，得到了每年需要处理污水的最小百分比，才能杜绝劣Ⅴ类水，将第Ⅳ、Ⅴ类水控制在20%内，从而才能保证我们有足够的饮用水     

杭州地区大中型水库富营养化状况及影响因子分析

在2008年和2009年对杭州地区17个大中型水库进行了调查。结果表明：杭州地区大中型水库水质不容乐观，按照单因子指标评价法，只有3个水库符合Ⅱ类水体标准，2个水库符合Ⅲ类水体标准，2个水库为Ⅳ类水体，3个水库为Ⅴ类水体，其余7个水库均为劣Ⅴ类水体，定类指标均是总氮。根据综合营养状态指数结果：丰水期2个水库处于贫营养状态，13个水库处于中营养状态，2个水库处于轻度富营养状态；枯水期16个水库处于中营养状态，1个水库处于中度富营养状态。总氮和总磷作为营养物质是这些水库富营养化的主要影响因素。位于山区源头地区的水库水质最好，位于平原城乡附近的水库其次，位于城市下游及城区附近的水库水质最差     

湖北省主要大中型水库富营养状况及特征分析

水库在城市供水、工业用水、水产养殖、农业灌溉、水利防汛以及景观旅游等方面发挥着重要的作用，但随着社会经济的发展，部分水库的富营养化状况日益严重，成为影响社会经济发展的重大环境问题。通过在2010年的3、6、7、10月对湖北省30座主要大中型水库进行布点采样，对水体的水质状况分别进行了调查、监测，采用《地表水环境质量标准》湖库标准进行水质类别分析，采用湖库营养状态指数法对湖泊富营养化评价, 并运用因子聚类分析方法对这些水库进行了类型划分。结果表明：30座大、中型水库有14座水库水质类别为Ⅱ类~Ⅲ类, 占467%; 有8座水库水质类别为IV类，占267%；有8座水库水质类别为Ⅴ类或劣Ⅴ类，占267%；除白云湖水库为轻富营养化外，其余29座水库均属中营养状态；氨氮、磷作为营养物质是这些水库富营养化的主要影响因素，溶解氧对水体富营养化有重要影响，总氮、水温和有机物污染对水体富营养化产生较大影响；30座水库聚类分为城市工业废水污染源型、生活污水污染源型、农业非点源污染源型和养殖轻污染型4种水库类型。针对水库的污染类型，分别提出了减缓防治措施     

南淝河表层水中重金属空间分布、污染评价及来源

根据南淝河丰水期和枯水期水质的调查数据,采用单因子水质指数法和改进后的模糊综合评价法对水中重金属元素的污染进行了评价,确定了主要污染因子和优先控制断面,并利用主成分分析法对重金属污染进行了溯源分析。结果表明:Cr、Cu、Pb的含量平均值均为枯水期高于丰水期,而As、Cd的含量平均值均为枯水期低于丰水期。单因子水质指数法评价结果显示南淝河重金属污染的主要污染因子是Cd,丰水期和枯水期各采样点Cd的含量均达到地表水Ⅴ类水标准,最高值达到地表水Ⅴ类标准值的2.6倍。改进后模糊综合评价法评价结果显示南淝河水质丰水期基本属于地表水环境质量标准Ⅱ类水标准,潜山北路大桥断面污染最严重,属于优先控制断面,枯水期各断面水质均属于Ⅲ类水标准,整体上南淝河水质达到了水体功能区目标。主成分分析法结果显示,南淝河重金属污染的主要来源是流域内的农药化肥、机械制造和电镀行业的废水以及河道的行船。     

三峡水库水质变化趋势研究

为全面研究三峡水库蓄水之前至175 m蓄水运行期库区水质变化趋势和因蓄水导致水文条件变化后悬浮物、高锰酸盐指数、总磷等主要污染因子变化及其相互关系,通过对2000~2015年三峡水库水体水质状况进行分析,得出如下结论:三峡水库干流水质较好,其受水期及水库蓄水调度影响明显但逐渐减弱。受蓄水导致的水流条件变化、上游来水、支流汇入及沿程点面源污染等因素影响,干流沿程各断面水质变化趋势不完全一致;除清溪场和沱口断面外,从库尾到库首水质评价结果优于Ⅲ类的比例总体呈上升趋势。受蓄水影响,御临河、小江、大宁河及香溪河河口断面水质均呈下降趋势。三峡水库上游来水悬浮物含量变化与水期存在较好相关性,但自2013年开始上游来水各水期悬浮物含量均下降,悬浮物通量较2013年之前平均降低约80%。水库库中、库首断面近年来悬浮物含量在丰水期和平水期下降,其后逐渐趋于稳定,枯水期变化不明显。蓄水后主要支流河口悬浮物含量大部分时段低于库区干流同期,上游支流河口断面悬浮物含量受水期影响较库区中下游支流河口明显。干支流各断面高锰酸盐指数和总磷在各水期变化趋势各异,上游断面丰水期变化较下游断面明显;随着蓄水进程,各断面高锰酸盐指数和总磷在平水期和枯水期之间、断面间差异越来越小。悬浮物含量与高锰酸盐指数、总磷等参数之间存在一定的相关性,但在较长时间范围,不能通过拟合等手段将水样一种状态的测定结果推出样品另一种状态近似检测结果。     

红枫湖水质变化趋势及原因分析

红枫湖是贵阳市重要的饮用水源地,自2007年集中治理以来,水质不断好转,基本达到预期目标。对红枫湖流域7个断面及4条入湖支流水质进行监测,研究2003~2012年10年的水质变化趋势和2013年年内变化趋势,并对引发水质变化的原因进行分析。结果表明,从2003年到2007年红枫湖水质急剧恶化,从Ⅲ类降到劣Ⅴ类;经过6年的集中治理,水质提升至目前的Ⅲ类、局部Ⅱ类,整体处于中营养状态,但受内源污染和外源生活污染等影响,部分断面仍存在TP、NH3-N、COD等超标现象。湖库水质季节性变化明显,受降雨及气温影响,在6月和7月出现轻度富营养化,其余月份均处于中营养状态。红枫湖4条入湖支流水质受到不同程度的污染,2011年后水质状况好转,但支流水体呈现受生活污染源污染的显著特征,主要表现为BOD5、粪大肠菌群超标。因此,对影响水质的污染源还需要增加处理设施,加强管理,以达到水源地水质的要求。     

河流综合水质评价方法比较研究

为探讨综合水质评价结论的科学合理性,对典型的7种河流综合水质评价方法,包括单因子评价法、污染指数法、模糊评价法、灰色系统评价法、层次分析法、人工神经网络法、水质标识指数法,在归类分析其特性的基础上,针对代表性的评价样本,进行了综合水质评价比较研究。主要结论为：①单因子评价法以最差水质指标所属类别作为综合水质类别,评价结论表现为过保护;②污染指数法能够直观判断综合水质是否达到功能区目标,但是不能判断综合水质类别;③对模糊数学法、灰色系统评价法、层次分析法、BP人工神经网络法和水质标识指数法等5种典型评价方法,当综合水质为Ⅰ~Ⅴ类水情形时,这几种方法评价结论基本一致,证明这5种典型评价方法对Ⅰ~Ⅴ类水的评价结论具有科学合理性;④当综合水质为劣Ⅴ类水时,模糊数学法、灰色系统评价法、层次分析法、BP人工神经网络法的评价结论偏保守,而水质标识指数法解决了劣Ⅴ类水质的连续性描述问题,能够对劣Ⅴ类水进行科学合理评价,并对Ⅰ~Ⅴ类水、劣Ⅴ类水不黑臭、劣Ⅴ类水黑臭进行全面、科学合理的定性与定量评价.     

岷江汤坝航电枢纽工程对水环境的影响研究

为研究长江上游岷江航电的开发对水环境带来的影响,选取岷江航电梯级水库中的第二级汤坝航电枢纽工程为研究对象.利用2016年的监测数据,分析了现状年库区渠化河段来流负荷,通过构造MIKE21水动力水质数学模型,对汤坝建成前、汤坝建成后和Ⅲ类来水情况下渠化河段的水质变化进行了数值模拟,分析了支流汇入后的污染带变化,并计算了3种情景下的水环境容量.结果 表明,现状年库区渠化河段来流污染源负荷主要来源于岷江干流.汤坝建成后,坝前CODcr和NH3-N浓度均满足Ⅲ类水质标准,TP浓度属劣Ⅴ类;在Ⅲ类来水情况下,坝前CODcr、NH3-N浓度满足Ⅲ类水质标准,TP浓度属Ⅴ类.支流汇入渠化河段形成的污染带面积较天然状态下发生变化:除镇江河和筒车河NH3-N不形成污染带以及太和河NH3-N的污染带面积减小外,其余支流水质因子污染带面积均较建设前增加.汤坝建成后,坝址处CODcr的水环境容量减少3280 t/a,NH3-N水环境容减少368t/a,TP无剩余水环境容量;Ⅲ类来水情况下,CODcr和NH3-N的水环境相比建设前减少,TP无剩余水环境容量.筒车河三类水质因子水环境容量增加,而镇江河水环境容量减小,建坝前后太和河均无剩余水环境容量.研究可为岷江航电污染源削减及应对措施的指定提供科学依据.     

三峡工程蓄水运用期库区干流水质分析

分析了三峡库区蓄水前后（1998～2009年）干流水质的变化及原因。结果表明，同蓄水前相比，蓄水后库区干流水质变好，库区干流断面月度达标率均值由蓄水前的623%变为蓄水后的783%，库区干流超标污染物主要为高锰酸盐指数、总磷、铅等。蓄水后水质时空分布出现新的特点，近坝水体悬浮物、浑样高锰酸盐指数、总磷、铅等可吸附污染物浓度显著降低。蓄水后年内悬浮物及浑样高锰酸盐指数、总磷和铅浓度仍然是丰水期＞平、枯水期，但近坝水体不同水期间浓度差别比蓄水前明显减小。蓄水后，库区干流浑样高锰酸盐指数、总磷、铅浓度整体上表现为从库尾至库首沿程下降，尤以丰水期沿程下降最为突出。浑样高锰酸盐指数、总磷、铅浓度以上变化特征主要缘于库区水位抬高后，流速减小导致的澄清作用，即高锰酸盐指数所代表污染物、磷、铅等随泥沙发生了不同程度的沉降。蓄水前后清样高锰酸盐指数和总磷未发生明显变化，156 m蓄水后至今，清样铅浓度明显低于蓄水前。     

丹江口水质变化及影响因素分析

水库水质变化情况在湖库生态安全的调查与评价中占有重要的地位，同时也为生态安全监测与预警，生态安全保障，以及湖库综合治理方案的发展提供了基础和依据。将高锰酸钾指数，氨氮以及其它一些参数选作为主要的评价因子，并对丹江口水库近年来的水质变化进行分析。同时，对影响水库水质的因素，包括水库的水量，上游来水，农业非点源污染等，以及它们与丹江口水库水质变化的联系也做了探索和分析，并根据分析提出了改善丹江口水库水质的建议。总而言之，丹江口水库的水质近年来通过环境保护和污染控制等逐渐变好，同时也正在向更好的方向改善。丹江口水库水质变化主要与非点源污染相关，另外，水质监测系统需要进一步完善     

WSSD 2002, Latin America and Brazil: Biodiversity and Indigenous People

Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources.     

The Phenomenon of Pseudoviviparity in Alpine and Arctomontane Grasses (DeschampsiaBeauv., FestucaL., and PoaL.)

It is known that pseudoviviparous plant taxa are most numerous in the Arctic and high mountain regions, where they sometimes account for a noticeable part of the local flora and play an important phytocenotic role. The complex of pseudoviviparous taxa is an interesting model for investigating the processes of hybridogenic speciation, as various mechanisms stabilizing the hybrid genetic systems proved to be effective in them. In particular, this concerns vast and taxonomically complex groups such as the genera Deschampsia, Festuca, and Poa.In this paper, published data on the taxonomy, chromosome numbers, and distribution of pseudoviviparous grasses in the Arctic regions and subarctic mountain systems are reviewed.     

Conservation, commercialisation and confusion: harvesting of Ischyrolepis in a coastal forest, South Africa

Harvesting of non-timber forest products is an integral component of rural livelihoods throughout the developing world. At times this is at odds with conservation objectives. Reconciliation of the two requires examination of local level contexts and needs. This paper reports on the harvesting needs for Ischyrolepis by a rural community in South Africa, against the setting that they had recently been prohibited from harvesting by the local conservation officials. Interviews were conducted with conservation officials to understand the reasoning for the prohibition. Local demand for Ischyrolepis was assessed by household surveys, as well as in-depth interviews with traders. The density and size class distribution of Ischyrolepis was determined using transects. The total annual demand for Ischyrolepis was determined to be approximately only 2.7% of the standing crop. The bulk of the annual demand was for small-scale trade, the income from which was a primary source of income for the few harvesters. Very little evidence could be found indicating that harvesting was damaging the resource or its habitat, and local knowledge suggested that the abundance of the species was stimulated by harvesting. Even if market demand were to increase, the size of the shoots required means that less than 20% of the standing crop could be harvested annually. Current regulations around harvesting are in a state of revision, and hence confusion prevails regarding if harvesting is permissible, and if so, under what conditions, which is detrimental to both conservation and livelihoods. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Radionuclide content of building materials and associated gamma dose rates in Egyptian dwellings

Studies have been carried out to determine the natural radioactivity in some building materials (bricks, tiles, marble and ceramics) and their associated radiation hazard. The radioactivity concentrations of ²²⁶Ra ²³²Th and ⁴⁰K were measured using a gamma spectrometer with a Hp–Ge detector. The activities of ²³⁸U and ²³⁴U were measured using an alpha-spectrometer with a surface barrier detector after applying a radiochemical procedure. The ²³⁴U/²³⁸U isotopic ratios were calculated. The radium equivalent activities and the radiation hazard index associated with the natural radionuclides were calculated. A computer program was developed and applied to calculate the dose rate a person will receive from the walls of a room constructed from the studied building materials.     

Education for Sustainable Development: The Johannesburg Summit and Beyond

The World Summit on Sustainable Development (WSSD), held in Johannesburg during 26 August and 4 September 2002, was a truly remarkable event, not least because it identified and committed the world community to what has to be done to realise Agenda 21 objectives. Discussion begins with the "means of implementation" of the Johannesburg Plan of Implementation (JPI). Education for, and raising awareness of, sustainable development are the key commitments in the "means of implementation". The issues central to these commitments are discussed. The crucial role of moral philosophy in education for sustainable development is then discussed. Defining the "problem" as lack of progress (in fact negative progress between Rio and Johannesburg) towards global sustainable development, a cause–effect relationship of the "problem" is developed based on a systematic and logical analysis. It shows that the "cause" is West's profoundly materialistic, environment-degrading and exploitative attitude and activities to satisfy grossly unsustainable, hedonistic and insatiably avaricious Western life-styles – life-styles that are held up by the West as "ideal" fruits of economic "development" to be aspired by all. The "effects" are pollution of air, water and soil; mounting loss of biodiversity, ecosystems and species; relentlessly widening north–south divide, etc. It is argued that while science and technology can address some of the "effects", they cannot address the "cause". Only moral philosophy can by fundamentally re-orienting moral values genuinely to respect nature and the environment. Based on sound and tested principles of Educational Psychology, a proposal is then made for including moral philosophy in the formal curricula (content and pedagogy) of primary, secondary and higher education for instilling in children and young people genuinely environment-respecting moral values. To this end a generic syllabus for the secondary level is proposed. Finally, it is argued that if the scientific community really believes that science or technology alone can radically change the pervasive environment-degrading moral values to those that genuinely respect the environment, thus paving the way to real global sustainability, then it must demonstrate how this could be done and explain why, despite their abundant science and technology, the developed nations are the biggest polluters and consumers with grossly unsustainable life-styles. Certainly, examples would be much more convincing than rhetoric or tired old clichés about how science and technology alone could deliver global sustainable development.     

Do nanoparticles present ecotoxicological risks for the health of the aquatic environment?

Nanotechnology is a major innovative scientific and economic growth area, which may present a variety of hazards for environmental and human health. The surface properties and very small size of nanoparticles and nanotubes provide surfaces that may bind and transport toxic chemical pollutants, as well as possibly being toxic in their own right by generating reactive radicals. There is a wealth of evidence for the harmful effects of nanoscale combustion-derived particulates (ultrafines), which when inhaled can cause a number of pulmonary pathologies in mammals and humans. However, release of manufactured nanoparticles into the aquatic environment is largely an unknown. This review addresses the possible hazards associated with nanomaterials and harmful effects that may result from exposure of aquatic animals to nanoparticles. Possible nanoparticle association with naturally occurring colloids and particles is considered together with how this could affect their bioavailability and uptake into cells and organisms. Uptake by endocytotic routes are identified as probable major mechanisms of entry into cells; potentially leading to various types of toxic cell injury. The higher level consequences for damage to animal health, ecological risk and possible food chain risks for humans are also considered based on known behaviours and toxicities for inhaled and ingested nanoparticles in the terrestrial environment. It is concluded that a precautionary approach is required with individual evaluation of new nanomaterials for risk to the health of the environment. Although current toxicity testing protocols should be generally applicable to identify harmful effects associated with nanoparticles, research into new methods is required to address the special properties of nanomaterials.     

Household water in rural asia: a case study of the construction of a piped water system in Bangui,Ilocos Norte,Philippines

In early 1980 an extension agent was assigned to the rural municipality of Bangui, Ilocos Norte, Philippines to work on development projects – in particular the improvement of the supply of safe water for drinking and sanitation. After many months of visiting spring sites and meeting with community leaders, a small part of the municipality was selected to build a gravity fed piped water system. Although the system took many months to plan, identify funding and construct, the 600 community members were ultimately rewarded with house to house connections that enabled them to achieve per capita water consumption levels above the minimum levels recommended by the World Health Organization. Of course, money was critical to ensure the project’s success, but many other factors played an equally critical role. For instance, without the active participation of the community and the unwavering support of the community leadership the project would not have survived the initial planning stage. Also, the extension agent played a critical role by acting as a conduit between funding agencies, the Bureau of Public Works and the community. The primary lesson to be learned from this experience is that the success of rural development projects is largely driven by the synergy between the community, technical support, financial support, and agents of change such as extension agents. If any of these ingredients had been lacking, the project result would likely have been far different.