Effects of eutrophication and exotic crayfish on health status of two Spanish lakes: a joint application of ecological indicators

Lake Sentiz and Lake Chozas are two small water bodies in the Province of León (NW Spain). The former is mesotrophic and the latter went from oligotrophic to turbid in 1997, due to introduction of an invasive allochthonous crayfish Procambarus clarkii (Rodríguez et al., 2003, Rodríguez et al., 2005, Marchi et al., 2011a, Marchi et al., 2011b). We set out to study health status of the two ecosystems by the joint use of different but correlated ecological indicators, supplementing the values obtained by monitoring campaigns. We examine three scenarios: (1) Lake Sentiz, (2) Lake Chozas before and (3) Lake Chozas after the biological invasion. We evaluate eco-exergy, emergy and eco-exergy–empower ratio, three holistic ecological indicators based on the thermodynamics of far-from-equilibrium systems. When structural changes take place in ecosystems it is recommended to apply holistic thermodynamic indicators as presented in Jørgensen et al., 2010a, Jørgensen et al., 2010b. We propose their joint application for a complete overview of the monetary value of natural capital, because they provide information added to statistical analysis and direct measurement. The aim is to determine which of these indicators best represents the effects of eutrophication and perturbations caused by alien species in the two freshwater systems. The eco-exergy–empower ratio gives the best results, since it clearly indicates lake efficiency in transforming direct and indirect solar energy inputs into organization. The eco-exergy (work capacity) results are used to estimate ecosystem services and quantify the economic value of lake natural capital. Calculation of ecosystem services on an eco-exergy basis provides good indications of monetary gains or losses possible in perturbed systems, including eutrophic or invaded ecosystems. This is not surprising, because work capacities include all possible services offered by ecosystems, not only the services actually used by humans. Eco-exergy and the eco-exergy–empower ratio can be guidelines for the calculation of ecosystem services, although they give only a partial indication of the environmental costs and benefits of a given level of information. The present results suggest political and economic considerations and solutions, and are a useful example for organisations involved in environmental management of pollution and biological invasions by exotic species.     

Adjustment of Forest Ecosystem Root Respiration as Temperature Warms

Adjustment of ecosystem root respiration to warmer climatic conditions can alter the autotrophic portion of soil respiration and influence the amount of carbon available for biomass production. We examined 44 published values of annual forest root respiration and found an increase in ecosystem root respiration with increasing mean annual temperature (MAT),but the rate of this cross-ecosystem increase (Q10 = 1.6) is less than published values for short-term responses of root respiration to temperature within ecosystems (Q10 = 2-3). When specific root respiration rates and root biomass values were examined, there was a clear trend for decreasing root metabolic capacity (respiration rate at a standard temperature) with increasing MAT. There also were tradeoffs between root metabolic capacity and root system biomass, such that there were no instances of high growing season respiration rates and high root biomass occurring together. We also examined specific root respiration rates at three soil warming experiments at Harvard Forest, USA, and found decreases in metabolic capacity for roots from the heated plots. This decline could be due to either physiological acclimation or to the effects of co-occurring drier soils on the measurement date. Regardless of the cause, these findings clearly suggest that modeling efforts that allow root respiration to increase exponentially with temperature, with Qt0 values of 2 or more, may over-predict root contributions to ecosystem CO2 efflux for future climates and underestimate the amount of C available for other uses,including net primary productivity.     

Ecological complexity effects on thermal signature of different Madeira island ecosystems

From a systemic perspective, evolution and natural succession promote the creation of efficient biological structures and processes that capture and dissipate the solar energy, maximizing the entropy production. This ecological complexification results in better ecosystem thermodynamic performance indicated by lower temperature.In a brief period of evolutionary time human-induced disturbance has altered profoundly the structure and functioning of the Earth System, i.e. ecological simplification.The objective is to understand whether remote sensing data can be considered appropriate proxy indicators to test if more mature and complex ecosystems have higher entropy production rates which lead to lower and attenuated ecosystem temperatures.Simple remote sensing measurements of Madeira Island for Thermal Infrared Radiation and Normalized Difference Vegetation Index were used to analyse the surface temperature and biomass cover of Madeira ecosystems spectrum of different states of human-induced disturbance.The findings revealed it was possible to distinguish between ecosystem types using thermodynamic indicators, where older ecosystems with more complex structures exhibit more attenuated lower average temperatures.It was also found that habitat heterogeneity can represent either artificial (human) or natural disturbance with opposite consequences in the ecosystem thermal signature, i.e. lower temperature when natural disturbance and higher if anthropogenic disturbance.Simple thermal remote sensing data can be used as systemic indicator of ecosystem health by reflecting it levels of eco-exergy, i.e the available work energy in the ecosystem.     

Ecosystem services and their values: a case study in the Qinba mountains of China

Terrestrial ecosystem services can provide both direct and indirect economic benefits. In this case study, we estimated the annual economic value of some ecosystem services provided by terrestrial ecosystems in the Qinba mountains of Shaanxi Province of China, using both simulation models and a geographic information system that helps to analyze the effect of ecological factors on ecosystem functions. With respect to differences in vegetation types and their coverage, by combining the latest research, and using theory and methods for the value of terrestrial ecosystem services, we not only calculated goods produced by different types of vegetation but also estimated the value of various terrestrial ecosystem services. We also set up a database and an eco-account of a terrestrial ecosystem. The ecosystem services assessed relate to the following aspects: the vegetations primary productivity, soil and fertility conservation, water conservation, carbon fixation and oxygen supply. The total economic value of terrestrial ecosystem services in the Qinba mountains was estimated to be 968.33 billion renminbi per year, and represents a part of the actual ecosystem services. In addition, we analyzed the spatial distribution of the vegetation based on the economic values of the terrestrial ecosystem services. Our findings can contribute to the conservation of these terrestrial ecosystems and the effective use of these ecosystem services.     

Biomass flow and structure of a tropical upwelling ecosystem in La Guajira, Colombian Caribbean

La Guajira is an exploited tropical upwelling ecosystem in the Colombian Caribbean coast. A trophic model of 27 functional groups was constructed using the ECOPATH 5.0 Beta software to integrate the available information on the ecosystem. The model allowed a comparison with other trophic flow models of upwelling ecosystems. Total system biomass (68 t/km2/year), net system production (1,248.5 t/km2/year), and total system throughput (3,275 t/km2/year) make La Guajira moderate when compared with other systems. The largest amount of energy throughput is achieved from trophic level I to II (68.93 %), although an important proportion of the total flow originates from detritus (32 %). The production/respiration ratio exceeds 1, suggesting that La Guajira is an immature ecosystem and is in development, as determined by its low ascendency (33.7 %) and high development capacity (66.3 %), similar to other upwellings that have values of ascendency between 20 % and 35 %. Although the basic input data were good and covered 1995 to 2000, appropriate information is still not available on some trophic groups such as biomass (for phytoplankton, invertebrates, catfishes and pelagic predator fishes), secondary production data (invertebrates, pelagic predator fishes, and small pelagic fishes), and seabird and mammal populations, which are top trophic levels and an essential part of upwelling ecosystems.     

Integrated ecosystem health assessment based on eco-exergy theory: A case study of the Jiangsu coastal area

The main objective of ecosystem health management is to preserve the capacity of ecosystems to respond to disturbances and future changes. We proposed a set of ecological indicators for coastal ecosystem health assessment using physical stressors such as total suspended matter, chemical stressors including nutrients and heavy metal pollutants, community structure metrics including species richness, diversity and evenness, and ecosystem level eco-exergy indicators. The results of our case study indicate that the health status of the Jiangsu coastal ecosystem is limited by environmental stressors and factors that affect the community species diversity. The health status of nektonic and benthic communities is reflected by water quality and sediment physicochemical properties, respectively. The results of our case study demonstrate that the integrated ecological health indicator system can provide a comprehensive assessment that corresponds with the current health of coastal ecosystems and a reliable theoretical basis for regional coastal management.     

区域生态保护修复碳汇潜力评估方法与应用——基于第一批山水林田湖草生态保护修复工程的研究

山水林田湖草生态保护修复工程是生态系统恢复的有效措施,借助生态保护与修复提升生态系统固碳潜力,无疑是土地利用碳减排的新路径。基于山水林田湖草沙综合整治视角,从生态系统的格局和质量两个方面评估了第一批山水林田湖草生态保护修复工程的实施效果,并借助InVEST模型定量化地分析了工程实施前后的生态系统碳汇能力。结果如下：(1)山水林田湖草生态保护修复试点工程加速了各类生态系统间的相互转化,主要表现为城镇生态系统的增加、农田生态系统的减少;工程区植被覆盖度整体提高,NDVI值平均水平不断上升、高值区逐步扩大,劣质、低质生态系统改造成果显著,陆地生态系统质量有效提升。(2)试点区生态系统碳汇能力和潜力得到有效改善,工程累积增加碳汇面积22.68%,其中工程实施前期增加碳汇面积18.06%,中后期增加面积4.62%;工程实施后2018年碳汇总量增加32.74 Tg, 2020年碳汇总量增加31.28 Tg,年均碳汇潜力的提升约1.24%;工程在增加生态系统质与量、碳汇潜力的巩固与提升上具有显著成效。分析结果表明,生态保护修复是实现“双碳”目标的必然选项,这也是生态保护修复在实现“双碳”目标中的基本...     

实验增温对陆地生态系统根系生物量的影响

根系是植物吸收土壤水分和养分的重要器官, 驱动着多个生态系统过程, 该研究揭示了实验增温对根系生物量的影响及机制, 可为气候变暖背景下土壤碳动态和生态系统过程的变化提供理论依据。该研究从已发表的151篇国内外研究论文中收集到611组数据, 通过整合分析(meta-analysis)方法研究了实验增温对根系生物量(根系总生物量、粗根生物量、细根生物量、根冠比)的影响, 并探讨了增温幅度、增温年限、增温方式的影响, 以及根系生物量对增温的响应与本底环境条件(生态系统类型、年平均气温、年降水量、干旱指数)的关系。结果表明: (1)模拟增温使细根生物量显著增加8.87%, 而对根系总生物量、粗根生物量、根冠比没有显著影响; (2)中等强度增温(1-2 ℃)使得细根生物量和根冠比分别提高14.57%和23.63%; 中短期增温实验(<5年)对细根生物量具有促进影响, 而长期增温实验(≥5年)使细根生物量有降低的趋势; 开顶箱增温和红外辐射增温分别使细根生物量显著提高了17.50%和12.16%, 而电缆加热增温使细根生物量和粗根生物量显著降低了23.44%和43.23%; (3)不同生态系统类型对于增温响应不一致, 模拟增温使苔原生态系统细根生物量显著提高了21.03%, 细根生物量对增温的响应与本底年平均气温、年降水量、干旱指数均呈显著负相关关系。     

Study on change in value of ecosystem service function of Tarim River

The characteristic of change in value of Tarim River ecosystem service function and its causes are discussed by combining the remote-sensing images with social statistical data related to the change in land utilization of Tarim River Main stream area during 1973–2005 and applying correlation analysis, regressional analysis and principal component analysis methods. The results show a right ascension state in the value of Tarim River ecosystem service function over the past 30 years. Of which, the Cropland ecosystem service function is of the largest increment in the economic value, which is far in excess of other ecosystem systems; the capacity of forest, grassland and wetland in service supply and value attribution show a downward tendency relatively; the area of Cropland and unused land ecosystems increase while that of forest, grassland and wetland ecosystems decrease, which indicates that the integral capacity and balance of the ecosystem in the region investigated has been affected severely and the ecosystem deteriorated; the economic activity of human is the key factor to regulate the change in economic value of Tarim River ecosystem service function and its trend in development.     

农牧交错带风蚀沙化区农业生态系统服务功能的经济价值评估

运用市场价值法、替代工程法、影子价格法和机会成本法等方法对内蒙古阴山北麓风蚀沙化区农业生态系统服务功能的价值进行了经济评估。结果表明 ,该地区农业生态系统总的服务价值为 4 6 5 4 5 381 0万元 ,其中产品服务价值为 2 9874 1万元 (占 0 0 6 % ) ,水土保持价值为 4 5 70 2 84 2万元 (占 9 7% ) ,涵养水源价值为 4 2 80 2 6万元 (占 0 0 9% ) ,气候调节价值为393411 8万元 (占 0 84 % ) ,营养物质循环价值为 4 1910 6 73 9万元 (占 89 2 7% ) ,从服务功能的价值比例来看 ,系统的环境服务价值要远远大于其产品服务的价值 ,表明该地区农业生产水平落后 ,同时也体现了在当地环境恶劣 ,农业经营粗放的前提下 ,系统环境服务价值是维系其不稳定农业生产的基础     

青藏高原高寒灌丛生态系统草本层生物量分配格局

青藏高原高寒灌丛生态系统生物量分配的研究相对较少,尤其是其草本层。为了探究高寒灌丛生态系统草本层生物量分配特征及其影响因素,分析了青藏高原东北部灌丛生态系统的49个高寒灌丛样地的草本层地上与地下生物量特征及其气候因子之间的关系。结果表明1)草本层地上生物量与地下生物量分别为121.1,342.8 g/m2均大于高寒草地的地上生物量与地下生物量。2)草本层的根冠比为3.6低于高寒草地的根冠比。3)地上生物量与地下生物量之间呈现幂函数的关系y=8.0x0.83(R2=0.48,P0.001)。4)根冠比与年均温度、年均降雨量之间没有显著的相关关系。     

Endangered fishes and economics: intergenerational obligations

Synopsis The diversity of fishes is declining worldwide, largely as the result of habitat alterations created by decisions that foster short-term economic gain. While the best arguments for preserving endangered fishes and ecosystems are non-economic arguments, they have been relatively ineffective. Therefore, it is necessary to provide economic arguments as well. Fish in general have high market values and are a vital source of protein for humans but these values have contributed more to their decline than to their conservation. Fish also have high value as indicators of the health of ecosystems which provide many services to humans, such as clean water. This has not prevented the degradation of aquatic ecosystems, although the value of fisheries has occasionally justified ecosystem protection. Existence values have been developed as a way of putting an economic value on some of the less tangible aspects of fish and ecosystems but they also make it possible to justify extinctions. If the continuous increase in the number of endangered fishes and aquatic ecosystems is to be halted, then the economic costs of environmental degradation to future generations must be included as part of the cost of doing business today (intergenerational value). Political action is needed to protect fishes and aquatic habitats against the day when more benign economic and philosophical systems become predominant.Invited essay     

Valuation of ecosystem services in alternative bioenergy landscape scenarios

Agricultural land in the Midwest is a source of food and fuel, as well as biodiversity. It is also a cause of excess nutrients that make their way to the Mississippi River and the Gulf of Mexico. To address unsustainable changes to biogeochemical cycles and ecosystem functions, a multidisciplinary approach involving social science, natural science, and engineering is often effective. Given the potential of second‐generation biofuels, and capitalizing on the deep‐rooted perennial bioenergy crops capable of thriving in poor soils, we demonstrated an integrated socio‐environmental analysis of the impacts of growing switchgrass within row‐crop landscapes in Illinois. In this study, we model land use scenarios that incorporate switchgrass as a biofuel crop in a Midwest corn‐belt watershed using the Soil Water Assessment Tool coupled with an economic analysis for the Vermilion Basin in Illinois. We estimated the values of ecosystem services under an alternative bioenergy landscape, including commodity and bioenergy crops, changes in biogeochemistry, and recreational services. The estimated annual values of nitrate and sediment reduction attributed to bioenergy crops range from $38 million to $97 million and $16,000 to $197,000, respectively. The annual value of carbon dioxide emission reduction ranges from $1.8 million to $6.1 million based on the initial crop rotation pattern. Estimated average annual values for wildlife viewing, water‐based recreation, and pheasant hunting are $1.24 million, $0.17 million, and $0.3 million, respectively. To our knowledge, this study represents the first effort to comprehensively quantify ecosystem services using a process‐based model, and estimate their value in an alternative bioenergy landscape. The information we generate could aid in understanding the potential for biomass production from marginal land and the total economic value of the landscape at various spatial scales. The framework is useful in fostering alternative bioenergy landscapes with synergies in a food, energy, and conservation nexus.     

不同发展模式对城市生态系统调节服务价值的影响

快速城市化加快了城市生态系统格局的改变,导致生态系统服务价值下降,对城市可持续发展造成阻碍。为了探究何种城市发展模式能够创造更高的生态系统服务价值,以深圳为案例,利用2010年、2015年和2020年生态系统类型数据,设置经济、惯性和生态3种不同的发展模式,并使用CA-Markov模型对2025年深圳市各类生态系统变化进行预测。在此基础上创新性地核算了不同模式下的关键生态系统服务价值。结果显示：（1）2015年到2020年,各类生态系统呈现不同变化趋势,人类聚落生态系统快速增长,对各类自然生态系统造成侵占,城区绿地呈现自然减少人工增加趋势。（2）2025年3种发展模式对生态系统类型变化影响显著,惯性发展模式下人类聚落、城区绿地出现扩张,经济发展模式下进一步增长,自然生态系统面积显著减少,生态发展模式下自然生态系统面积得到恢复。（3）3种模式下的生态系统服务价值变化差异显著,惯性和经济发展模式下,生态系统服务价值显著下降,分别较2020年下降2.67%和5.25%。生态发展模式下,生态系统服务价值提高,较经济发展模式提升5.5%,3种模式生态系统调节服务总价值差最高达到38.1亿元。综合来看,未来的发展模式应当选择以生态保护为优先的发展模式,通过制定有效的生态空间保护措施如生态保护红线划定、城市潜在开发区调整,实施生态工程等提高城市生态空间面积和质量,维持和提高生态系统服务价值,实现经济发展与生态保护的协调并行。     

Economic valuation of kelp forests in northern Chile: values of goods and services of the ecosystem

Kelp beds, besides being one of the most important benthic resources in northern Chile, provide a variety of environmental goods and services. In order to evaluate economically the wild kelp populations in northern Chile (26° to 32° S) more than simply their commercial value as a source of raw materials for alginate extraction, we used several economic indicators to holistically assess the value of a group of brown seaweeds of economic importance, Lessonia spp. and Macrocystis pyrifera: (1) market value of biomass as a source of raw material for extraction of alginic acid, (2) market value of associated species of economic importance, (3) value as a source of scientific information, (4) value as a climate buffer (CO₂ capture and release of O₂), (5) value of associated biodiversity (non-commercial species), (6) value as cultural heritage and (7) value as a reservoir of biodiversity. Existence values of kelp beds which estimate the willingness of citizens to pay and work without payment to preserve the ecosystem were calculated using the contingent valuation technique. The results indicate that kelp beds in northern Chile have a total value of US $540 million. Of this total, kelp fishery accounts for 75 % and associated-species fisheries account for 15 %. In this context, the economic value of Chilean kelp beds is mainly associated with the industry of alginate extraction. By contrast, existence value as a source of scientific information or environmental buffer for CO₂ capture or O₂ production represents only 9 % of the total value, representing a very low relative importance to society. The economic valuation of coastal resources and marine ecosystems is a complementary tool for decision making and implementation of public policies related to the conservation and sustainable exploitation of renewable resources and their ecosystems.     

On ecosystem production

We have discussed some aspects of the production and efficiency of energy use in aquatic ecosystems. Ecosystem production is defined as the difference between the gross total primary production and total expenditures for metabolic processes in all organisms of the ecosystem. We have obtained equations showing the dependence of ecosystem production on the average depth of a waterbody and the share of the primary production of phytoplankton in the total production. The mean value of the coefficient of ecosystem efficiency in some waterbodies (53%) indicates that aquatic ecosystems use energy efficiently. The efficiency of the energy use increases with an increase in the biomass turnover rate. High production in the ecosystem can be obtained if its structure is simpler.     

基于能值分析和生态用地分类的中国生态系统生产总值核算研究

生态系统生产总值是生态系统为人类提供的产品与服务价值的总和,研究与建立一个独立的核算一个国家或地区的生态系统生产总值的方法与体系,对科学评价与合理利用自然资源、助推生态文明建设等具有重要意义。将生态系统生产总值分为供给价值、文化价值、承载价值与调节价值等四大类,基于能值分析方法和生态用地分类体系,计算得出全国及各地区生态系统生产总值,并将其与国内生产总值进行比较,为自然资源资产负债核算和综合生态系统管理等研究提供理论和方法借鉴。研究结果表明:(1)生态用地分类体系包括湿地、森林、草地和其他生态土地4个一级类型、19个二级类型。其中,湿地、森林、草地可统称为基础性生态用地。2008年,中国生态用地总量为763.95万km2,约占陆域国土面积的80%,其中基础性生态用地约为530.8万km2。(2)2008年,中国国土生态系统生产总值约为19万亿美元,是当年国内生产总值4.71万亿美元的4倍,人均生态系统总值约为1.45万美元/人。从生态系统生产总值来看,广东、山东、河南位居前三,西藏最低;从人均生态系统生产总值来看,西藏和内蒙古居前,甘肃最低。     

海岛生态系统服务价值评估及其时空变化——以浙江舟山金塘岛为例

生态系统服务价值研究是目前生态学研究的热点之一,海岛生态系统的特殊性令其更易受人类活动和环境变化的影响。文章在海岛生态系统服务价值当量修订的基础上,对典型海岛金塘岛1986—2014年的生态系统服务价值进行评估,分析了金塘岛近30年来生态系统服务价值的时空动态变化。结果表明:城镇生态系统面积持续增加,其他生态系统类型面积不同程度减少,减少的生态系统类型大多数转化为城镇。1986—2014年金塘岛的生态系统服务总价值呈下降趋势,共减少了1.08亿元,减少了30.23%,其中湿地与森林的生态系统服务价值量减少最多,城镇的价值变化率最大。空间上表现为价值极低区域沿着人类活动方向呈现急剧扩大趋势。生态系统提供的产品与服务在数量和质量上逐步下降,不利于海岛的可持续发展。该研究为海岛地区生态系统服务价值当量修订提供参考,同时对转变海岛经济发展方式,促进海岛可持续发展提供基础信息与决策依据。     

The relationship between biodiversity and ecosystem functioning in food webs

Recent theoretical and experimental work provides clear evidence that biodiversity loss can have profound impacts on functioning of natural and managed ecosystems and the ability of ecosystems to deliver ecological services to human societies. Work on simplified ecosystems in which the diversity of a single trophic level is manipulated shows that diversity can enhance ecosystem processes such as primary productivity and nutrient retention. Theory also strongly suggests that biodiversity can act as biological insurance against potential disruptions caused by environmental changes. However, these studies generally concern a single trophic level, primary producers for the most part. Changes in biodiversity also affect ecosystem functioning through trophic interactions. Here we review, through the analysis of a simple ecosystem model, several key aspects inherent in multitrophic systems that may strongly affect the relationship between diversity and ecosystem processes. Our analysis shows that trophic interactions have a strong impact on the relationships between diversity and ecosystem functioning, whether the ecosystem property considered is total biomass or temporal variability of biomass at the various trophic levels. In both cases, food-web structure and trade-offs that affect interaction strength have major effects on these relationships. Multitrophic interactions are expected to make biodiversity–ecosystem functioning relationships more complex and non-linear, in contrast to the monotonic changes predicted for simplified systems with a single trophic level.