932 resultados para BIOLOGICAL DIVERSITY
Resumo:
Coastal and marine ecosystems support diverse and important fisheries throughout the nation’s waters, hold vast storehouses of biological diversity, and provide unparalleled recreational opportunities. Some 53% of the total U.S. population live on the 17% of land in the coastal zone, and these areas become more crowded every year. Demands on coastal and marine resources are rapidly increasing, and as coastal areas become more developed, the vulnerability of human settlements to hurricanes, storm surges, and flooding events also increases. Coastal and marine environments are intrinsically linked to climate in many ways. The ocean is an important distributor of the planet’s heat, and this distribution could be strongly influenced by changes in global climate over the 21st century. Sea-level rise is projected to accelerate during the 21st century, with dramatic impacts in low-lying regions where subsidence and erosion problems already exist. Many other impacts of climate change on the oceans are difficult to project, such as the effects on ocean temperatures and precipitation patterns, although the potential consequences of various changes can be assessed to a degree. In other instances, research is demonstrating that global changes may already be significantly impacting marine ecosystems, such as the impact of increasing nitrogen on coastal waters and the direct effect of increasing carbon dioxide on coral reefs. Coastal erosion is already a widespread problem in much of the country and has significant impacts on undeveloped shorelines as well as on coastal development and infrastructure. Along the Pacific Coast, cycles of beach and cliff erosion have been linked to El Niño events that elevate average sea levels over the short term and alter storm tracks that affect erosion and wave damage along the coastline. These impacts will be exacerbated by long-term sea-level rise. Atlantic and Gulf coastlines are especially vulnerable to long-term sea-level rise as well as any increase in the frequency of storm surges or hurricanes. Most erosion events here are the result of storms and extreme events, and the slope of these areas is so gentle that a small rise in sea level produces a large inland shift of the shoreline. When buildings, roads and seawalls block this natural migration, the beaches and shorelines erode, threatening property and infrastructure as well as coastal ecosystems.
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The St. Croix East End Marine Park (STXEEMP) was established in 2003 as the first multi-use marine park managed by the U.S. Virgin Islands Department of Planning and Natural Resources. It encompasses an area of approximately 155 km2 and is entirely within Territorial waters which extend up to 3 nautical miles from shore. As stated in the 2002 management plan, the original goals were to: protect and maintain the biological diversity and other natural values of the area; promote sound management practices for sustainable production purposes; protect the natural resource base from being alienated for other land use purposes that would be detrimental to the area’s biological diversity; and to contribute to regional and national development (The Nature Conservancy, 2002). At the time of its establishment, there were substantial data gaps in knowledge about living marine resources in the St. Croix, and existing data were inadequate for establishing baselines from which to measure the future performance of the various management zones within the park. In response to these data gaps, National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment, Biogeography Branch (CCMA-BB) worked with territorial partners to characterize and assess the status of the marine environment in and around the STXEEMP and land-based stressors that affect them. This project collected and analyzed data on the distribution, diversity and landscape condition of marine communities across the STXEEMP. Specifically, this project characterized (1) landscape and adjacent seascape condition relevant to threats to coral reef ecosystem health, and (2) the marine communities within STXEEMP zones to increase local knowledge of resources exposed to different regulations and stressors.
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This monograph studies the progress achieved by conservation partners in South Africa on the implementation of the Convention on Biological Diversity (CBD) Programme Element Two components of governance, participation, equity and benefit sharing, from the perspective of small-scale fishing communities. It explores the strategies and mechanisms used by different authorities to create the conditions whereby local communities can benefit from marine protected areas (MPAs), of which South Africa has gazetted 24, highlighting examples of best practice. The monograph will be useful for researchers, scientists, fishworker organizations, environmentalists and anyone interested in the protection of marine biodiversity and the promotion of sustainable fisheries management.
Resumo:
常绿阔叶林以其富饶的生物资源、丰富的生物多样性和巨大的生态与环境效益引起了人们越来越大的重视,它的研究已成为国际植被科学界关注的主题之一。我国分布着世界上面积最大的亚热带常绿阔叶林,在世界植被中具有重要地位,它的分布表现出明显的地带性差异,存在着多样的植物群系及其对应的气候特征。但是在植物功能性状领域,与全球范围其它生物群系相比,常绿阔叶林物种的研究较少,其功能性状间、功能性状与环境间的关系尚不清晰。 本研究以常绿阔叶林木本植物的当年生小枝为对象,试图从小枝水平上的生物量分配格局、叶片大小与数量的权衡关系、小枝茎的构型效应、叶片元素化学计量学,以及小枝大小的成本与效益分析等方面,较为系统地揭示小枝水平上的植物功能性状间及其与气候间的关系。因此,在华西雨屏带内部的不同纬度设置峨眉-青城-雷波-平武的温度梯度进行比较,并对有降水差异的川西南偏湿性(雷波)与偏干性常绿阔叶林(西昌)进行对比研究,同时在不同山体进行不同海拔梯度的比较研究。 本文主要研究结果如下: (1)小枝生物量分配格局叶水平上,叶片重-叶柄重(Y轴vs.X轴,下同)呈斜率小于1的异速生长关系,表明叶柄对叶内部的生物量分配影响显著。小枝水平上,叶和茎的生物量以及它们与小枝总生物量间基本呈等速生长关系,表明大的小枝或大叶物种不一定在叶生物量的分配上占优势。不同生活型间,在小枝或者茎的生物量一定时,常绿物种叶片的生物量比例较落叶物种稍高。与温度和水分较优越(峨眉及其低海拔)的生境相比,在相对低湿(螺髻)与低温(平武)的生境中的植物会减少对叶的投入而增加对支撑部分的投资比例。 (2)小枝叶片大小与数量的权衡无论是不同气候带还是不同生活型以及不同海拔梯度,叶片大小与出叶强度基本都是呈负的等速生长关系,表明了叶片大小-数量在小枝水平上的权衡。在不同气候梯度的对比中,叶片数量(出叶强度)一定时,高温和高水分生境(峨眉)比低温(平武)和低湿(螺髻山)生境中的物种的叶片大小(质量和面积)更大,表明不同生境的比较中,小的叶片可能具有较高的出叶强度和更高的适合度收益。“出叶强度优势”(Leafingintensitypremium)假说可能不适宜解释不同生境物种叶片大小差异。 (3)小枝茎的构型效应虽然茎长和茎径与叶片大小都呈正相关关系,与出叶强度都呈负相关关系,但茎长/茎径比与叶/茎生物量之比呈负相关关系;与叶片的大小呈负相关关系,与出叶强度呈正相关关系。这说明小枝构型能影响小枝叶/茎生物量分配和叶大小-数量的权衡关系。其影响机制可能是小枝内部的顶端优势。另外,茎长/茎径比在低湿和低温等不利生境中的植物中较高,而在降水和温度较适宜环境中较低。 (4)叶片C、N、P化学计量学N含量和P含量,C/N比和比叶重(LMA,leafmassperarea)呈正的等速生长关系,而N和LMA,P和LMA呈负的等速生长关系。在LMA一定时,C/N比随着生境胁迫压力的增加而降低,N、P含量随着生境压力的增加而增加。在P含量一定时,N含量随着生境压力的增加而降低,即N/P比在生境条件较优(峨眉及其低海拔)时较高。常绿和落叶植物叶片的N/P比没有差异,在LMA一定时,常绿植物的N、P含量较高、C/N比较低。总之,植物的C、N、P化学计量学特征受叶片属性如LMA与气候,及其相互作用的影响。 (5)小枝大小的代价与效益分析、TLA与小枝总重总叶面积(TLA,totalleafarea,Y轴,下同)与总叶重(X轴)均呈斜率小于1的异速生长关系,TLA与小枝横切面积呈斜率为1的等速生长关系。表明叶片面积的增加总是小于叶重和小枝总重的增加,随着小枝的增大,它的叶面积支撑效率下降。在热量和降水优越的生境(峨眉及其低海拔)中,相同小枝重或者相同茎横切面积的小枝,其叶面积支撑效率较低湿与低温环境下(螺髻山、平武及高海拔)的高。 总体上,本文初步研究了小枝水平上可能存在的以下三种权衡关系:叶-茎生物量分配权衡;叶片大小-数量的权衡;小枝茎长-茎径的权衡关系,以及气候要素等对这三种权衡关系的影响。在此基础上,我们还讨论了这些权衡关系的可能形成机制,及其与物种生态适应的联系。本研究丰富了生活史对策中关于权衡关系的研究内容,为我国常绿阔叶林功能生态学研究积累了材料。 Evergreen broad-leaved forests are attracting much more attention from vegetation ecologists than ever before because of their abundant nature resource and biological diversity, and also great ecological benefits. China has the largest distribution of subtropical evergreen broad-leaved forests (temperate rainforests) that are typical and representative in the world. The forests span over more than ten degrees in latitude and more than 30 degrees in longitude, providing an ideal place to study plant functional ecology, i.e., the climatic effect on plant functional traits and the relationship between the traits. However, relative to the other biomes, there are few studies addressing functional ecology of the plant species from subtropical evergreen broad-leaved forests. In this study, I focused on the leaf size-twig size spectrum of the woody species of subtropical evergreen broad-leaved forests in southwestern china. I collected data on leaf size and number, twig size in terms of both mass and volume, and stem architecture from five temperate mountains, and then I analyzed the relationships between leaf and stem biomass and between leaf size and number, the effect of stem length/diameter ratio on biomass allocation and on the relationship between leaf size and number, leaf C:N:P stoichiometry, and the twig efficiency of supporting leaf area in relation to twig size. I also addressed the climate effect on the spectrum. The temperature gradient from warm to cool sites was represented by Emei Mountain, Qingchengshan, Leibo, and Pingwu, and the rainfall gradient was assumed to emerge from the comparison between Leibo (High) and Luojishan (Low). In addition, altitudinal effects were analyzed with comparisons between low and high altitudes for each mountains. My main results are as follows. Isometric relationships were found between leaf mass and twig mass and between lamina mass and twig mass, suggesting that the biomass allocation to leaves or laminas was independent of twig mass. Petiole mass disproportionably increase with respect to lamina mass and twig mass, indicating the importance of leaf petioles to the within-twig biomass allocation. In addition, the investigated species tended to have a larger leaf and lamina mass, but a smaller stem mass at a given twig mass at favorable environments including warm and humid sites or at low altitude than unfavorable habitats, which might be due to the large requirements in physical support and transporting safety for the species living at unfavorable conditions. Moreover, the evergreen species invested more in leaves and laminas than the deciduous at given stem or twig biomass within any specified habitats. Negative, isometric scaling relationships between leaf number and size broadly existed in the species regardless of climate, altitude, and life forms, suggesting a leaf size/number trade-off within twigs. Along the climatic gradients, at given leaf number or leafing intensity, the leaves were larger in the favorable environments than the poor habitats. This suggested that the fitness benefit gained by small leaves could be larger than that with high leafing intensity in the stressful sites. I concluded that the “leafing intensity premium” hypothesis was not appropriate to interpreting between-habitat variation in leaf size. Both stem length and diameter were positively correlated to leaf size but negatively correlated to leafing intensity. The ratio of stem length to diameter was negatively correlated to leaf mass fraction, and it was negatively correlated to leaf size but positively correlated to leafing intensity. This suggested that the stem architecture influenced twig biomass allocation and the relationship between leaf size and number. The mechanism underlying the architectural effect might lie in the apical dominance within twig. Moreover, the ratio was greater in unfavorable habitats but smaller in favorable environments. Positive, isometric relationships were found between N and P contents per leaf mass, and between C/N ratio and leaf mass per area (LMA), but N and P contents scaled negatively to LMA. C/N ratio decreased but N and P increased with increasing habitat stress at a given LMA. N content declined with increasing habitat stress at given P content. These indicated that N/P and C/N were higher but LMA was lower in favorable habitats than in the other circumstances. The evergreen and deciduous species were non-heterogeneous in N/P, but the evergreen species have higher N and P contents and lower C/N than the deciduous ones. In general, C:N:P stoichiometry were related to both climatic conditions and other important functional traits like LMA. Total leaf area (TLA) allometricly scaled to leaf mass with a slope shallower than 1, similar to the relationship between TLA and total twig mass (leaf mass plus stem mass), suggesting that TLA failed to keep pace with the increase of leaf mass and twig size. However, TLA scaled isometricly to twig cross-sectional area. Thus, it could be inferred that the twig efficiency of displaying leaf area decreased with increasing twig size. In addition, the efficiency at a given twig size was large in favorable than unfavorable habitats. In general, in this preliminary study, I studied three tradeoff relationships within twigs, i.e., between leaf and stem biomass, between leaf number and size, and between stem length and diameter, as well as the climatic effect on the relationships. I discussed the mechanisms underlying the tradeoff relationships in view of biophysics and eco-physiology of plants. I believe that this study can serve as important materials advancing plant functional ecology of subtropical forest and that it will improve the understanding of life history strategies of plants from this particular biome.
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The most biological diversity on this planet is probably harbored in soils. Understanding the diversity and function of the microbiological component of soil poses great challenges that are being overcome by the application of molecular biological approaches. This review covers one of many approaches being used: separation of polymerase chain reaction (PCR) amplicons using denaturing gradient gel electrophoresis (DGGE). Extraction of nucleic acids directly from soils allows the examination of a community without the limitation posed by cultivation. Polymerase chain reaction provides a means to increase the numbers of a target for its detection on gels. Using the rRNA genes as a target for PCR provides phylogenetic information on populations comprising communities. Fingerprints produced by this method have allowed spatial and temporal comparisons of soil communities within and between locations or among treatments. Numerous samples can be compared because of the rapid high throughput nature of this method. Scientists now have the means to begin addressing complex ecological questions about the spatial, temporal, and nutritional interactions faced by microbes in the soil environment.
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As one of the most typical wetlands, marsh plays an important role in hydrological and economic aspects, especially in keeping biological diversity. In this study, the definition and connotation of the ecological water storage of marsh is discussed for the first time, and its distinction and relationship with ecological water requirement are also analyzed. Furthermore, the gist and method of calculating ecological water storage and ecological water requirement have been provided, and Momoge wetland has been given as an example of calculation of the two variables. Ecological water use of marsh can be ascertained according to ecological water storage and ecological water requirement. For reasonably spatial and temporal variation of water storage and rational water resources planning, the suitable quantity of water supply to marsh can be calculated according to the hydrological conditions, ecological demand and actual water resources.
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The context: Soil biodiversity and sustainable agriculture; Abstracts - Theme 1: Monitoring and assessment: Bioindicators of soil health: assessment and monitoring for sustainable agriculture; Practical tools to measure soil health and their use by farmers; Biological soil quality from biomass to biodiversity - importance and resilience to management stress and disturbance; Integrated management of plant-parasitic nematodes in maize-bean cropping systems; Microbial quantitative and qualitative changes in soils under different crops and tillage management systems in Brazil; Diversity in the rhizobia associated with Phaseolus vulgaris L: in Ecuador and comparisons with Mexican bean rhizobia; Sistemas integrados ganadería-agricultura en Cuba; Soil macrofauna as bioindicator of soil quality; Biological functioning of cerrado soils; Hydrolysis of fluorescein diacetate as a soil quality indicator in different pasture systems; Soil management and soil macrofauna communities at Embrapa Soybean, Londrina, Brazil; Soil macrofauna in a 24 - year old no-tillage system in Paraná, Brazil; Invertebrate macrofauna of soils inpastures under different forms of management in the cerrado (Brazil); Soil tillage modifies the invertebrate soil macrofauna community; Soil macrofauna in various tillage and land use systems on an oxisols near Londrina, Paraná, Brazil; Interference of agricultural systems on soil macrofauna; Scarab beetle-grub holes in various tillage and crop management systems at Embrapa Soybean, Londrina, Brazil; Biological management of agroecosystems; Soil biota and nutrient dynamics through litterfall in agroforestry system in Rondônia, Amazônia, Brazil; Soil-C stocks and earthworm diversity of native and introduced pastures in Veracruz, Mexico; Theme 2 : Adaptive management: Some thoughts on the effects and implications of the transition from weedy multi-crop to wead-free mono-crop systems in Africa; Towards sustainable agriculture with no-tillage and crop rotation systems in South Brazil; Effect of termites on crusted soil rehabilitation in the Sahel; Management of macrofauna in traditional and conventional agroforestry systems from India with special reference to termites and earthworms; Adaptive management for redeveloping traditional agroecosystems; Conservation and sustainable use of soil biodiversity: learning with master nature!; Convergence of sciences: inclusive technology innovation processes for better integrated crop/vegetation, soil and biodiversity management; Potential for increasing soil biodiversity in agroecosystems; Biological nitrogen fixation and sustainability in the tropics; Theme 3: Research and innovation: Plant flavonoids and cluster roots as modifiers of soil biodiversity; The significance of biological diversity in agricultural soil for disease suppressiveness and nutrient retention; Linking above - and belowground biodiversity: a comparison of agricultural systems; Insect-pests in biologically managed oil and crops: the experience at ICRISAT; Sistemas agricolas micorrizados en Cuba; The effect of velvetbean (Mucuna pruriens) on the tropical earthworm Balanteodrilus pearsei: a management option for maize crops in the Mexican humid tropics; The potential of earthworms and organic matter quality in the rehabilitation of tropical soils; Research and innovation in biological management of soil ecosystems; Application of biodynamic methods in the Egyptian cotton sector; Theme 4: Capacity building and mainstreaming: Soil ecology and biodiversity: a quick scan of its importance for government policy in The Netherlands; Agrotechnological transfer of legume inoculants in Eastern and Southern Africa; Agricultura urbana en Cuba; Soil carbon sequestration for sustaining agricultural production and improving the environment; Conservation and sustainable management of below-ground biodiversity: the TSBF-BGBD network project; The tropical soil biology and fertility institute of CIAT (TSBF); South-South initiative for training and capacity building for the management of soil biology/biodiversity; Strategies to facilititate development and adoption of integrated resource management for sustainable production and productivity improvement; The challenge program on biological nitrogen fixation (CPBNF); Living soil training for farmers: improving knowledge and skills in soil nutrition management; Do we need an inter-governmental panel on land and soil (IPLS)? Protection and sustainable use of biodiversity of soils; Cases Studies -- Plant parasitic nematodes associated with common bean (Phaseolus vulgaris L.) and integrated management approaches; Agrotechnological transfer of legume inoculants in Eastern and Southern Africa; Restoring soil fertility and enhancing productivity in Indian tea plantations with earthworms and organic fertilizers; Managing termites and organic resources to improve soil productivity in the Sahel; Overview and case studies on biological nitrogen fixation: perspectives and limitations; Soil biodiversity and sustainable agriculture: an overview.
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The Census of Marine Life aids practical work of the Convention on Biological Diversity, discovers and tracks ocean biodiversity, and supports marine environmental planning.
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Interactions between natural selection and environmental change are well recognized and sit at the core of ecology and evolutionary biology. Reciprocal interactions between ecology and evolution, eco-evolutionary feedbacks, are less well studied, even though they may be critical for understanding the evolution of biological diversity, the structure of communities and the function of ecosystems. Eco-evolutionary feedbacks require that populations alter their environment (niche construction) and that those changes in the environment feed back to influence the subsequent evolution of the population. There is strong evidence that organisms influence their environment through predation, nutrient excretion and habitat modification, and that populations evolve in response to changes in their environment at time-scales congruent with ecological change (contemporary evolution). Here, we outline how the niche construction and contemporary evolution interact to alter the direction of evolution and the structure and function of communities and ecosystems. We then present five empirical systems that highlight important characteristics of eco-evolutionary feedbacks: rotifer-algae chemostats; alewife-zooplankton interactions in lakes; guppy life-history evolution and nutrient cycling in streams; avian seed predators and plants; and tree leaf chemistry and soil processes. The alewife-zooplankton system provides the most complete evidence for eco-evolutionary feedbacks, but other systems highlight the potential for eco-evolutionary feedbacks in a wide variety of natural systems.
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Claims of injustice in global forest governance are prolific: assertions of colonization, marginalization and disenfranchisement of forest-dependent people, and privatization of common resources are some of the most severe allegations of injustice resulting from globally-driven forest conservation initiatives. At its core, the debate over the future of the world's forests is fraught with ethical concerns. Policy makers are not only deciding how forests should be governed, but also who will be winners, losers, and who should have a voice in the decision-making processes. For 30 years, policy makers have sought to redress the concerns of the world's 1.6 billion forest-dependent poor by introducing rights-based and participatory approaches to conservation. Despite these efforts, however, claims of injustice persist. This research examines possible explanations for continued claims of injustice by asking: What are the barriers to delivering justice to forest-dependent communities? Using data collected through surveys, interviews, and collaborative event ethnography in Laos and at the Tenth Conference of Parties to the Convention on Biological Diversity, this dissertation examines the pursuit of justice in global forest governance across multiple scales of governance. The findings reveal that particular conceptualizations of justice have become a central part of the metanormative fabric of global environmental governance, inhibiting institutional evolution and therewith perpetuating the justice gap in global forest governance.
Ecosystem services, targets, and indicators for the conservation and sustainable use of biodiversity
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After the collective failure to achieve the Convention on Biological Diversity's (CBD's) 2010 target to substantially reduce biodiversity losses, the CBD adopted a plan composed of five strategic goals and 20 “SMART” (Specific, Measurable, Ambitious, Realistic, and Time-bound) targets, to be achieved by 2020. Here, an interdisciplinary group of scientists from DIVERSITAS – an international program that focuses on biodiversity science – evaluates these targets and considers the implications of an ecosystem-services-based approach for their implementation. We describe the functional differences between the targets corresponding to distinct strategic goals and identify the interdependency between targets. We then discuss the implications for supporting research and target indicators, and make several specific suggestions for target implementation.
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We present the first remotely operated vehicle investigation of megabenthic communities (1004-1695 m water depth) on the Hebrides Terrace Seamount (Northeast Atlantic). Conductivity-temperature-depth casts showed rapid light attenuation below the summit and an oceanographic regime on the flanks consistent with an internal tide, and high short-term variability in water temperature, salinity, light attenuation, aragonite and oxygen down to 1500 m deep. Minor changes in species composition (3-14%) were explained by changes in depth, substratum and oceanographic stability, whereas environmental variability explained substantially more variation in species richness (40-56%). Two peaks in species richness occurred, the first at 1300-1400 m where cooler Wyville Thomson Overflow Water (WTOW) mixes with subtropical gyre waters and the second at 1500-1600 m where WTOW mixes with subpolar mode waters. Our results suggest that internal tides, substrate heterogeneity and oceanographic interfaces may enhance biological diversity on this and adjacent seamounts in the Rockall Trough.
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The degree of development and operability of the indicators for the Marine Strategy Framework Directive (MSFD) using Descriptor 1 (D1) Biological Diversity was assessed. To this end, an overview of the relevance and degree of operability of the underlying parameters across 20 European countries was compiled by analysing national directives, legislation, regulations, and publicly available reports. Marked differences were found between countries in the degree of ecological relevance as well as in the degree of implementation and operability of the parameters chosen to indicate biological diversity. The best scoring EU countries were France, Germany, Greece and Spain, while the worst scoring countries were Italy and Slovenia. No country achieved maximum scores for the implementation of MSFD D1. The non-EU countries Norway and Turkey score as highly as the top-scoring EU countries. On the positive side, the chosen parameters for D1 indicators were generally identified as being an ecologically relevant reflection of Biological Diversity. On the negative side however, less than half of the chosen parameters are currently operational. It appears that at a pan-European level, no consistent and harmonized approach currently exists for the description and assessment of marine biological diversity. The implementation of the MSFD Descriptor 1 for Europe as a whole can therefore at best be marked as moderately successful.
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Ecosystem services provided by the marine environment are fundamental to human health and well-being. Despite this, many marine systems are being degraded to an extent that may reduce their capacity to provide these ecosystem services. The ecosystem approach is a strategy for the integrated management of land, water and living resources that promotes conservation and sustainable use in an equitable way (UN Convention on Biological Diversity, 2000). Its application to marine management and spatial planning has been proposed as a means of maintaining the economic and social value of the oceans, not only in the present but for generations to come. Characterising the susceptibility of services (and combinations of services) to particular human activities based on knowledge of impacts on biodiversity and ecosystem functioning (as described in preceding chapters) is a challenge for future management of the oceans. In this chapter, we highlight the existing, but limited knowledge of how ecosystem services may be impacted by different human activities. We discuss how impacts on one service can impact multiple services and explore how the impacts on services can vary both spatially and temporally and according to context. We focus particularly on the effects on ecosystem services of activities whose impacts on biodiversity and ecosystem functioning have already been considered in previous chapters. Some of these activities are associated with poor management of ecosystem benefits, for example, from provisioning services (aquaculture and fisheries), or with excessive input of wastes, fertilisers and contaminants into the system overburdening the waste treatment and assimilation services. Other impacts are associated with the construction of structures or use of space designed to generate benefits from environmental services such as the presence of water as a carrier for shipping, or sources of wind, wave and tidal power. We discuss the trade-offs that are made, consciously or otherwise, between different ecosystem services, which arise from human activities to optimise or manage specific ecosystem services.
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Despite plant secondary metabolites being major determinants of species interactions and ecosystem processes, their role in the maintenance of biodiversity has received little attention. In order to investigate the relationship between chemical and biological diversity in a natural ecosystem, we considered the impact of chemical diversity in individual Scots pine trees (Pinus sylvestris) on species richness of associated ground vegetation. Scots pine trees show substantial genetically determined constitutive variation between individuals in concentrations of a group of secondary metabolites, the monoterpenes. When the monoterpenes of particular trees were assessed individually, there was no relationship with species richness of associated ground flora. However, the chemical diversity of monoterpenes of individual trees was significantly positively associated with the species richness of the ground vegetation beneath each tree, mainly the result of an effect among the non-woody vascular plants. This correlation suggests that the chemical diversity of the ecosystem dominant species has an important role in shaping the biodiversity of the associated plant community. The extent and significance of this effect, and its underlying processes require further investigation.