Neotropical wetlands: New instruments in ecosystem management

The management of wetland ecosystems in the neotropics is a challenging task due to the ecological, geographical and socio-political complexity of these areas. These difficulties are compounded by an incomplete knowledge of system dynamics and the potential impacts that economic activities may have on wetland ecosystem functioning. There is a growing body of potential tools that can be utilized to study and monitor these large complex ecosystems. These include the use of remote sensing information, in situ hydrological and microclimate sensors with long-term dataloggers, hydrological and ecological modelling approaches based on limited historical data, energy-based models, ecological-economic indicators of wetland resource use and others. We tested some of these approaches in an international research project dedicated to the study of a large Argentine wetland, the Esteros del Ibera (www.unisi.it/wetland). The study focused on examining and developing instruments for the management of Latin American wetlands. Local and regional decision makers are now using project-generated instruments to make decisions for wetland resource management. The creation of innovative decision-making tools for sustainable wetland-resource utilization is an important challenge for the future.This revised version was published online in March 2005 with corrections to the issue cover date.     

Where is the avoidance in the implementation of wetland law and policy?

Many jurisdictions in North America use a “mitigation sequence” to protect wetlands: First, avoid impacts; second, minimize unavoidable impacts; and third, compensate for irreducible impacts through the use of wetland restoration, enhancement, creation, or protection. Despite the continued reliance on this sequence in wetland decision-making, there is broad agreement among scholars, scientists, policymakers, regulators, and the regulated community that the first and most important step in the mitigation sequence, avoidance, is ignored more often than it is implemented. This paper draws on literature published between 1989 and 2010, as well as 33 semi-structured, key-informant interviews carried out in 2009 and 2010 with actors intimately involved with wetland policy in Alberta, Canada, to address key reasons why “avoidance” as a policy directive is seldom effective. Five key factors emerged from the literature, and were supported by interview data, as being central to the failure of decision-makers to prioritize wetland avoidance and minimization above compensation in the mitigation sequence: (1) a lack of agreement on what constitutes avoidance; (2) current approaches to land-use planning do not identify high-priority wetlands in advance of development; (3) wetlands are economically undervalued; (4) there is a “techno-arrogance” associated with wetland creation and restoration that results in increased wetland loss, and; (5) compensation requirements are inadequately enforced. Largely untested but proactive ways to re-institute avoidance as a workable option in wetland management include: watershed-based planning; comprehensive economic and social valuation of wetlands; and long-term citizen-based monitoring schemes.     

粤港澳大湾区湿地遥感监测与评估:现状、挑战及展望

粤港澳大湾区水热丰沛河网密布，岸线曲折峡湾众多，复杂的自然条件孕育了丰富的湿地资源，构成了区域生态安全屏障的重要防线。近几十年来气候变化与区域高强度人类活动的双重胁迫下，大湾区湿地资源面积衰减、质量退化趋势明显，亟需开展湿地资源监测与评估研究，为国家战略提供基础保障。现阶段湿地遥感已实现由最初的湿地面积、形态提取向湿地生物物理参量提取的过程转变，然而粤港澳大湾区特有的气候特征，限制了传统光学影像在湿地遥感领域的应用，大大提升了此区域长时间序列湿地遥感数据获取的难度。此外，如何实现湿地生态价值与生态资产对接与评估，也是现阶段自然资源监测管理面临的重大课题之一。本文基于粤港澳大湾区建设的国家战略需求，讨论湿地资源在构建大湾区生态安全保障体系中的重要地位，厘清大湾区湿地资源保护与利用存在的关键技术瓶颈与核心科学问题，围绕湿地遥感监测、湿地资源生态资产价值评估、湿地生态功能分区与定位等关键问题，指出开展粤港澳大湾区湿地遥感监测与评估面临的挑战，明确构建"天-空-地"湿地遥感监测的综合技术体系实施方案，并展望粤港澳大湾区湿地常态化监测与资产评估的几个重要方向：1构建适用于不同自然环境特征的湿地分类体系；2融合升级现有湿地监测与评估技术手段，发挥"天-空-地"一体化监测平台的技术优势；3全区域监测与重点调查相结合；4从调查监测迈向资源动态监控与演变机制分析；5面向陆海统筹的湿地区划与综合管治；6多学科、跨区域、跨行业协作。     

Advancing Science for Water Resources Management

Despite the major advances in science to underpin water resources and river management that have taken place over the past two decades, a need remains to establish a unifying framework that will lead to new, appropriate tools for water resources management. In Europe, this need has been highlighted by the promotion of the Water Framework Directive. From a scientific perspective, key questions focus on the ecological significance of flow variability over a range of timescales and the linkage between flow variability, habitat variability and biological population responses, and the biological interactions among these populations. Creation of scientifically sound tools requires development of knowledge at the level of first principles to realize sustainable developments within the context of adaptive management. Similitude analyses provide a mechanism for upscaling from fine ‘research’ scales to the coarser scales of water resource managers. Lack of appropriate data is the major obstacle to the development of these tools, especially those concerned with large rivers.     

An evaluation of ecological information on Australia’s northern tropical rivers and wetlands

The northern tropical river and wetland systems of Australia cover a vast and mostly remote area. Comparably little is known of wetland type, species diversity, ecological processes and ecosystem services. Systematic inventory and classification is lacking and research remains disparate in purpose and coverage. An integrated framework is used to evaluate results from three multidisciplinary studies across various scales to synthesise available knowledge relating to key ecological attributes across both the study region and within focus areas. The utility of geomorphic and hydrological classification at coarse scales is supported but the unavailability of biological data at corresponding and finer spatial and temporal scales constrains the potential for ecological inventory and classification utilising existing information. Future inventory and ecological studies across this and similar vast study areas need to consider the apriori development of a user-driven data framework and the development of specific investigatory tools to overcome technical and other barriers associated with the requirements of multi-scalar ecological studies.     

Community-based Monitoring of Natural Resource Use and Forest Quality in Montane Forests and Miombo Woodlands of Tanzania

A community-based monitoring system that focuses on natural resource use and forest quality in montane evergreen forest and miombo woodland areas was developed and implemented in 23 villages in 2002 as part of a participatory forest management regime in Iringa District, Tanzania. The scheme was developed to suit the needs and capacities of locally-elected natural resource committees managing and monitoring natural forests. Rather than measuring biodiversity, the monitoring is focused on resource extraction and disturbance. High levels of commitment to the monitoring were displayed by village level managers, and the preliminary feed-back indicates that the monitoring scheme provides them with the relevant information needed to suggest appropriate management interventions. While external support has been essential to cover development costs, natural resource revenue generated at village level can provide most of the running costs. Once developed, the scheme can, however, be transferred to similar areas at significantly lower costs that can be met by Tanzanian District budgets. Natural resource revenue generated from montane forests is generally much lower than in woodland areas due to restrictions on resource extraction imposed as a consequence of national and international interests. Opportunities to provide economic incentives for montane forest managers through direct utilisation of the resource are limited and it remains to be seen whether other non-economic incentives can sustain long term commitment in these biodiversity rich areas. Findings indicate that the key elements of this local resource utilisation monitoring scheme are simplicity, incentive mechanisms, transparency and accountability, and autonomy for local managers. However, the methods may not provide sufficient data on changes in biodiversity values in the high value forests and may need to be augmented by conventional monitoring by scientists funded by national or international institutions. Elements of the scheme are now being institutionalised within the forestry sector in Tanzania.     

Science and policy integration issues for stream and wetland jurisdictional determinations in a semi-arid region of the western U.S.

In the semi-arid western U.S., rivers and streams are becoming increasingly stressed and degraded, and wetlands lost, due to human development and associated management policies and actions that are generally ineffective for aquatic resources protection and restoration. There is often a significant disconnect between policy and management with science that leads to continued degradation of surface waters. Recent Supreme Court decisions and subsequent U.S. Army Corps of Engineers and Environmental Protection Agency guidance regarding determination of jurisdiction as ‘waters of the US’ that can be protected under Clean Water Act Section 404 (permitting discharge of dredged and fill materials into wetlands and other waters) is an example of this gap. This study identifies and evaluates key science and policy integration issues for stream and wetland jurisdictional determinations (JDs) in a semi-arid region of the western U.S., including much of the Rocky Mountains, Great Plains and Colorado Plateau. Issues discussed include identification and evaluation of navigable waters, hydrologic permanence/flow duration of perennial and intermittent/ephemeral streams, stream order, significant nexus, aggregation of waters and effects, human impacts and changes, resource inventories and tools, and JD outcomes. Recommendations are also presented to help address the identified issues for more effective management.     

Land-use and resource conflicts in the Okavango Delta, Botswana

This study assesses land-use conflicts in the Okavango wetland ecosystem. A survey of the livelihood activities of a sample of four villages has been carried out and a stakeholder approach used to identify and analyse the key actors involved in resource competition and conflicts in the area. Traditional and emerging stakeholders were identified and found to be in conflict not only with each other but within themselves. Institutional policies on land use in the area are not properly harmonized, and there has been a top-down approach to development planning and implementation of development programmes. As a result, land-use conflicts have escalated in the area. The Okavango Delta Management Plan adopted in 2007 should integrate and harmonize all the land-use policies, and land management in the area.     

Impact and management of purple loosestrife (Lythrum salicaria) in North America

The invasion of non-indigenous plants is considered a primary threat to integrity and function of ecosystems. However, there is little quantitative or experimental evidence for ecosystem impacts of invasive species. Justifications for control are often based on potential, but not presently realized, recognized or quantified, negative impacts. Should lack of scientific certainty about impacts of non-indigenous species result in postponing measures to prevent degradation? Recently, management of purple loosestrife (Lythrum salicaria), has been criticized for (1) lack of evidence demonstrating negative impacts of L. salicaria, and (2) management using biocontrol for lack of evidence documenting the failure of conventional control methods. Although little quantitative evidence on negative impacts on native wetland biota and wetland function was available at the onset of the control program in 1985, recent work has demonstrated that the invasion of purple loosestrife into North American freshwater wetlands alters decomposition rates and nutrient cycling, leads to reductions in wetland plant diversity, reduces pollination and seed output of the native Lythrum alatum, and reduces habitat suitability for specialized wetland bird species such as black terns, least bitterns, pied-billed grebes, and marsh wrens. Conventional methods (physical, mechanical or chemical), have continuously failed to curb the spread of purple loosestrife or to provide satisfactory control. Although a number of generalist insect and bird species utilize purple loosestrife, wetland habitat specialists are excluded by encroachment of L. salicaria. We conclude that (1) negative ecosystem impacts of purple loosestrife in North America justify control of the species and that (2) detrimental effects of purple loosestrife on wetland systems and biota and the potential benefits of control outweigh potential risks associated with the introduction of biocontrol agents. Long-term experiments and monitoring programs that are in place will evaluate the impact of these insects on purple loosestrife, on wetland plant succession and other wetland biota.     

Improving Health in Ucayali,Peru: A Multisector and Multilevel Analysis

We review the key determinants of health in Ucayali, Peru, identified by researchers, and, according to these, propose a set of tools to improve health in this area. Women and indigenous peoples are recognized as two vulnerable groups in the region that face greater health risks, and these are the main focus of the development of tools for health improvement. Also, the growing economic integration in the region facilitates the spread of infectious disease, thus requiring several levels of intervention. The tools discussed to improve health in Ucayali cross several scales and sectors. They include improved natural resource management, education and empowerment of women, integration of traditional and biomedical care, improved health information management, and community mobilization for health. Overall, our conclusions reinforce the limitations of the biomedical approach, which focuses on the treatment of specific pathologies in improving health. Health-system development requires the cooperation of many sectors and many actors across several spatial scales.     

An index of limnological conditions for urban wetlands of Bogotá city,Colombia

The urban wetlands of Bogotá are ecosystems of great importance, yet they are deteriorating. The state of deterioration must be evaluated in order to develop new methods of ecosystem monitoring and conservation. Here we describe the development of an index to assess the ecological health of five urban wetlands and one rural wetland from limnological data. The field phase of this study took place in November 2007 (rainy season) and February 2008 (dry season). Physical and chemical variables of the wetland ecosystems (temperature, dissolved oxygen, pH, conductivity, hardness, chlorides, ammonia, nitrites, nitrates, orthophosphates, and biological oxygen demand) were measured and samples of phytoplankton, periphyton, macroinvertebrates, and aquatic plants (macrophytes) were collected. The indices developed (biotic indices of communities: BI, and limnological conditions index: LICOI) allow classification of wetlands into three categories: those that have “acceptable limnological conditions” (Meridor, Jaboque and Guaimaral), those with “regular limnological conditions” (Santa María del Lago, Juan Amarillo) and those with “poor limnological conditions” (Tibanica). None of the environments studied fit a potential fourth category of “best limnological conditions.” The LICOI is a management tool that can be used to assess changes in wetlands after positive actions (restoration, cleaning, hydraulic management), or negative impacts (depletion, alien species, pollution). It also could allow regular monitoring of wetland evolution and serve as a basis for the development of indices measuring the ecological status of other aquatic environments in Colombia.     

Enabling tools for tissue engineering

Tissue engineering is a multidisciplinary field that combines engineering, physical sciences, biology, and medicine to restore or replace tissues and organs functions. In this review, enabling tools for tissue engineering are discussed in the context of four key areas or pillars: prediction, production, performance, and preservation. Prediction refers to the computational modeling where the ability to simulate cellular behavior in complex three-dimensional environments will be essential for design of tissues. Production refer imaging modalities that allow high resolution, non-invasive monitoring of the development and incorporation of tissue engineered constructs. Lastly, preservation includes biochemical tools that permit cryopreservation, vitrification, and freeze-drying of cells and tissues. Recent progress and future perspectives for development in each of these key areas are presented.     

广西黑水河湿地生物多样性现状与保护对策

广西黑水河湿地属于珠江水系,上游河段流经越南,系国际性河流,是中国17个生物多样性保护的关键地区之一,属于中越边境生物区,生态位保护具有跨国意义。2021年1月,采用路线法对黑水河湿地的生物多样性保护现状进行全流域实地考察,结果表明:黑水河湿地的生境类型多样,不仅汇集了繁多的生物种类,还孕育着生境交错地带特有的生物类群;湿地鱼类和鸟类物种多样性水平较高,湿地生物多样性等级属于一般水平,具有一定典型性和稀有性;黑水河湿地生物多样性保护和利用受到水质下降、生态环境污染、生物入侵及资源管理不到位等不利因素的影响,应该加强流域生境修复,健全相关法律法规,建立生物资源数据库,以湿地公园为依托,有效管理、合理开发利用湿地生物资源。     

Harmful algal blooms: causes,impacts and detection

Blooms of autotrophic algae and some heterotrophic protists are increasingly frequent in coastal waters around the world and are collectively grouped as harmful algal blooms (HABs). Blooms of these organisms are attributed to two primary factors: natural processes such as circulation, upwelling relaxation, and river flow; and, anthropogenic loadings leading to eutrophication. Unfortunately, the latter is commonly assumed to be the primary cause of all blooms, which is not the case in many instances. Moreover, although it is generally acknowledged that occurrences of these phenomena are increasing throughout the world's oceans, the reasons for this apparent increase remain debated and include not only eutrophication but increased observation efforts in coastal zones of the world. There is a rapidly advancing monitoring effort resulting from the perception of increased impacts from these HABs, manifested as expanding routine coastal monitoring programs, rapid development and deployment of new detection methods for individual species, toxins, and toxicities, and expansion of coastal modeling activities towards observational forecasts of bloom landfall and eventually bloom prediction. Together, these many efforts will provide resource managers with the tools needed to develop effective strategies for the management and mitigation of HABs and their frequently devastating impacts on the coastal environment.     

湿地退化研究进展

受经济发展、城市扩张、气候变化的影响,湿地退化已经成为全球性现象,是当前国际湿地科学前沿领域的热点。从湿地退化标准、退化特征、退化分级、退化过程、退化机理、退化监测体系、退化评价指标与指标体系、退化监测新技术及其生态恢复理论与技术9个方面系统地介绍了当前湿地退化研究进展。结果表明湿地退化过程、退化机理、退化评价指标体系和退化湿地监测、恢复与重建研究是当前研究的重点,在未来相当长的时间内,全球气候变化、湿地退化的微观过程与机理、湿地生态系统的可持续利用将会是重要的研究方向。最后就我国当前湿地退化研究存在的问题进行了分析,并提出近期湿地退化研究亟待开展的11项研究工作,供我国湿地退化研究工作者参考。     

The development of an assessment system to evaluate the ecological status of rivers in the Hindu Kush-Himalayan region: introduction to the special feature

Development of an Assessment System to Evaluate the Ecological Status of Rivers in the Hindu Kush-Himalayan Region (ASSESS-HKH) was a 3-year research project funded by the European Union (Contract number: INCO-CT-2005-003659). This article provides an overview of this research project by summarising the objectives, the approaches and the main achievements. The main objective was to develop and apply a biological assessment system to evaluate the river’s ecological quality and to provide a scientific basis for the identification of sustainable water policy options and management strategies. The assessment tools were jointly developed by European partners, who provided their experience from recent research activities (STAR, AQEM) and Asian partners, who provided the knowledge about Asian river catchments and management necessities. The project was organised into eight work packages defining the time line for all phases, such as establishment of a stream typology and definition of reference conditions and stages of impairment classes for the rivers in the Asian countries, including a review of existing policies for water management. A specific part of the project was dedicated to increasing the overall poor knowledge of benthic invertebrates in the region and their value to the classification of the river’s ecological quality. All activities were accompanied by information events for local residents, universities and water managers. A total of 396 multi-habitat samples, from 115 rivers in five different ecoregions, were taken in two different seasons and accompanied by information on 95 parameters describing river and catchment characteristics. The benthic invertebrates in the samples were taxonomically identified based on keys generated within the project. Taxalists, with abundances per site, and field protocol information were entered into a specifically developed software tool. This dataset was the basis for developing ecological river assessment methods, called HKHscreening (Rapid Field Assessment), HKHbios (HKH Biotic Score) and HKHindex (Multimetric Index). Furthermore, a software tool (ECODAT) for using these methods was developed. The monitoring tools will serve citizens and scientists of the Hindu Kush-Himalayan region and will provide a scientific basis for policy recommendations, mitigation strategies, transnational water resource planning and sustainable ecosystem management. Additional outputs, including all sampling and laboratory protocols and project deliverables, together with the freely downloadable software, are available at the following website: http://www.assess-hkh.at.     

Cross-fertilizing weed science and plant invasion science to improve efficient management: A European challenge

Both weed science and plant invasion science deal with noxious plants. Yet, they have historically developed as two distinct research areas in Europe, with different target species, approaches and management aims, as well as with diverging institutions and researchers involved. We argue that the strengths of these two disciplines can be highly complementary in implementing management strategies and outline how synergies were created in an international, multidisciplinary project to develop efficient and sustainable management of common ragweed, Ambrosia artemisiifolia. Because this species has severe impacts on human health and is also a crop weed in large parts of Europe, common ragweed is one of the economically most important plant invaders in Europe. Our multidisciplinary approach combining expertise from weed science and plant invasion science allowed us (i) to develop a comprehensive plant demographic model to evaluate and compare management tools, such as optimal cutting regimes and biological control for different regions and habitat types, and (ii) to assess benefits and risks of biological control. It further (iii) showed ways to reconcile different stakeholder interests and management objectives (health versus crop yield), and (iv) led to an economic model to assess invader impact across actors and domains, and effectiveness of control measures. (v) It also led to design and implement management strategies in collaboration with the various stakeholder groups affected by noxious weeds, created training opportunities for early stage researchers in the sustainable management of noxious plants, and actively promoted improved decision making regarding the use of exotic biocontrol agents at the national and European level. We critically discuss our achievements and limitations, and list and discuss other potential Old World (Afro-Eurasian) target species that could benefit from applying such an integrative approach, as typical invasive alien plants are increasingly reported from crop fields and native crop weeds are invading adjacent non-crop land, thereby forming new source populations for further spread.     

Development of community metrics to evaluate recovery of Minnesota wetlands

Monitoring wetland recovery requires assessment tools that efficiently and reliably discern ecosystem changes in response to changes in land use. The biological indicator approach pioneered for rivers and streams that uses changes in species assemblages to interpret degradation levels may be a promising monitoring approach for wetlands. We explored how well metrics based on species assemblages related to land use patterns for eight kinds of wetlands in Minnesota. We evaluated land use on site and within 500 m,1000 m, 2500 m and 5000 m of riverine, littoral, and depressional wetlands (n = 116) in three ecoregions. Proportion of agriculture, urban, grassland, forest,and water were correlated with metrics developed from plant, bird, fish, invertebrate, and amphibian community data collected from field surveys. We found79 metrics that relate to land use, including five that may be useful for many wetlands: proportion of wetland birds, wetland bird richness, proportion of insectivorous birds, importance of Carex, importance of invasive perennials. Since very few metrics were significant for even one-half of the wetland types surveyed, our data suggest that monitoring recovery in wetlands with community indicators will likely require different metrics,depending on type and ecoregion. In addition, wetlands within extensively degraded ecoregions may be most problematic for indicator development because biotic degradation is historic and severe. This revised version was published online in July 2006 with corrections to the Cover Date.