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991.
992.
A. Lara R. Urrutia R. Villalba B.H. Luckman D. Soto J.C. Aravena J. Mc Phee A. Wolodarsky L. Pezoa J. Len 《Dendrochronologia》2005,22(3):463-161
Water availability is one of the main limitations for future development and economic activity in many regions of the world. This applies even to areas of relatively high annual rainfall, such as the Valdivian Rainforest eco-region in Chile (35–48°S). Streamflow and water availability are crucial for several economic activities in the eco-region including hydroelectricity, irrigation, salmon farming, sports fishing of introduced trout and tourism. Scientific research focused on the spatial and temporal patterns of streamflow is a key element for planning the future development within the eco-region. In this paper we explore the potential of tree-rings for streamflow reconstruction in this region. Our preliminary results indicate a significant correlation (r=0.59 P<0.001, 1929–2000) between prior summer Río Bueno streamflow (January–April) and the average between a composite tree-ring chronology using Pilgerodendron uviferum from Chile and two composite Austrocedrus chilensis chronologies from Argentinean Patagonia. Similarly, there is a significant correlation (r=0.57, P<0.001, 1943–2002), between the Austrocedrus chronology (40°44′S) at Centinela in Argentinean Patagonia and the previous spring through early autumn (November–April) streamflow for Río Puelo. The tree-ring records used to correlate with Río Bueno and Río Puelo discharges show low-frequency variability and therefore the potential to reconstruct this variability in streamflow for the last 500–780 years. We also found a significant correlation between the composite Pilgerodendron standard ring-width chronology and the current summer water salinity (January–April) at the Reloncavi Estuary (r2=0.60, P<0.01, 1992–2000). Water salinity is a crucial determinant of the carrying capacity of salmon farming. Future research should provide reconstructions of streamflow, water salinity and other water quality attributes from tree-rings. These data will provide inputs to modeling scenarios of future water availability and are crucial to decision-making and planning of resource management and socio-economic development in the Valdivian Rainforest eco-region. 相似文献
993.
Status and prospects for renewable energy using wood pellets from the southeastern United States
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Virginia H. Dale Keith L. Kline Esther S. Parish Annette L. Cowie Robert Emory Robert W. Malmsheimer Raphael Slade Charles Tattersall SMITH Jr Thomas Bently Wigley Niclas S. Bentsen G?ran Berndes Pierre Bernier Miguel Brand?o Helena L. Chum Rocio Diaz‐Chavez Gustaf Egnell Leif Gustavsson J?rg Schweinle Inge Stupak Paul Trianosky Arnaldo Walter Carly Whittaker Mark Brown George Chescheir Ioannis Dimitriou Caspar Donnison Alison Goss Eng Kevin P. Hoyt Jennifer C. Jenkins Kristen Johnson Charles A. Levesque Victoria Lockhart Maria Cristina Negri Jami E. Nettles Maria Wellisch 《Global Change Biology Bioenergy》2017,9(8):1296-1305
The ongoing debate about costs and benefits of wood‐pellet based bioenergy production in the southeastern United States (SE USA) requires an understanding of the science and context influencing market decisions associated with its sustainability. Production of pellets has garnered much attention as US exports have grown from negligible amounts in the early 2000s to 4.6 million metric tonnes in 2015. Currently, 98% of these pellet exports are shipped to Europe to displace coal in power plants. We ask, ‘How is the production of wood pellets in the SE USA affecting forest systems and the ecosystem services they provide?’ To address this question, we review current forest conditions and the status of the wood products industry, how pellet production affects ecosystem services and biodiversity, and what methods are in place to monitor changes and protect vulnerable systems. Scientific studies provide evidence that wood pellets in the SE USA are a fraction of total forestry operations and can be produced while maintaining or improving forest ecosystem services. Ecosystem services are protected by the requirement to utilize loggers trained to apply scientifically based best management practices in planning and implementing harvest for the export market. Bioenergy markets supplement incomes to private rural landholders and provide an incentive for forest management practices that simultaneously benefit water quality and wildlife and reduce risk of fire and insect outbreaks. Bioenergy also increases the value of forest land to landowners, thereby decreasing likelihood of conversion to nonforest uses. Monitoring and evaluation are essential to verify that regulations and good practices are achieving goals and to enable timely responses if problems arise. Conducting rigorous research to understand how conditions change in response to management choices requires baseline data, monitoring, and appropriate reference scenarios. Long‐term monitoring data on forest conditions should be publicly accessible and utilized to inform adaptive management. 相似文献
994.
BackgroundAcute Lymphoblastic Leukemia (ALL) has a high survival rate, but cancer-related late effects in the early post-treatment years need documentation. Hospitalizations are an indicator of the burden of late effects. We identify rates and risk factors for hospitalization from five to ten years after diagnosis for childhood and adolescent ALL survivors compared to siblings and a matched population sample.Methods176 ALL survivors were diagnosed at ≤22 years between 1998 and 2008 and treated at an Intermountain Healthcare facility. The Utah Population Database identified siblings, an age- and sex-matched sample of the Utah population, and statewide inpatient hospital discharges. Sex- and birth year-adjusted Poisson models with Generalized Estimating Equations and robust standard errors calculated rates and rate ratios. Cox proportional hazards models identified demographic and clinical risk factors for hospitalizations among survivors.ResultsHospitalization rates for survivors (Rate:3.76, 95% CI = 2.22–6.36) were higher than siblings (Rate:2.69, 95% CI = 1.01–7.18) and the population sample (Rate:1.87, 95% CI = 1.13–3.09). Compared to siblings and population comparisons, rate ratios (RR) were significantly higher for survivors diagnosed between age 6 and 22 years (RR:2.87, 95% CI = 1.03–7.97 vs siblings; RR:2.66, 95% CI = 1.17–6.04 vs population comparisons). Rate ratios for diagnosis between 2004 and 2008 were significantly higher compared to the population sample (RR:4.29, 95% CI = 1.49, 12.32), but not siblings (RR:2.73, 95% CI = 0.54, 13.68). Survivors originally diagnosed with high-risk ALL did not have a significantly higher risk than siblings or population comparators. However, high-risk ALL survivors (Hazard ratio [HR]:3.36, 95% CI = 1.33–8.45) and survivors diagnosed from 2004 to 2008 (HR:9.48, 95% CI = 1.93–46.59) had the highest risk compared to their survivor counterparts.ConclusionsFive to ten years after diagnosis is a sensitive time period for hospitalizations in the ALL population. Survivors of childhood ALL require better long-term surveillance. 相似文献
995.
Multifunctionality is affected by interactions between green roof plant species,substrate depth,and substrate type
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Yann Dusza Sébastien Barot Yvan Kraepiel Jean‐Christophe Lata Luc Abbadie Xavier Raynaud 《Ecology and evolution》2017,7(7):2357-2369
Green roofs provide ecosystem services through evapotranspiration and nutrient cycling that depend, among others, on plant species, substrate type, and substrate depth. However, no study has assessed thoroughly how interactions between these factors alter ecosystem functions and multifunctionality of green roofs. We simulated some green roof conditions in a pot experiment. We planted 20 plant species from 10 genera and five families (Asteraceae, Caryophyllaceae, Crassulaceae, Fabaceae, and Poaceae) on two substrate types (natural vs. artificial) and two substrate depths (10 cm vs. 30 cm). As indicators of major ecosystem functions, we measured aboveground and belowground biomasses, foliar nitrogen and carbon content, foliar transpiration, substrate water retention, and dissolved organic carbon and nitrates in leachates. Interactions between substrate type and depth strongly affected ecosystem functions. Biomass production was increased in the artificial substrate and deeper substrates, as was water retention in most cases. In contrast, dissolved organic carbon leaching was higher in the artificial substrates. Except for the Fabaceae species, nitrate leaching was reduced in deep, natural soils. The highest transpiration rates were associated with natural soils. All functions were modulated by plant families or species. Plant effects differed according to the observed function and the type and depth of the substrate. Fabaceae species grown on natural soils had the most noticeable patterns, allowing high biomass production and high water retention but also high nitrate leaching from deep pots. No single combination of factors enhanced simultaneously all studied ecosystem functions, highlighting that soil–plant interactions induce trade‐offs between ecosystem functions. Substrate type and depth interactions are major drivers for green roof multifunctionality. 相似文献
996.
Ivan V. Monagan Jr. Jonathan R. Morris Alison R. Davis Rabosky Ivette Perfecto John Vandermeer 《Ecology and evolution》2017,7(7):2193-2203
Our knowledge of ecological interactions that bolster ecosystem function and productivity has broad applications to the management of agricultural systems. Studies suggest that the presence of generalist predators in agricultural landscapes leads to a decrease in the abundance of herbivorous pests, but our understanding of how these interactions vary across taxa and along gradients of management intensity and eco‐geographic space remains incomplete. In this study, we assessed the functional response and biocontrol potential of a highly ubiquitous insectivore (lizards in the genus Anolis) on the world's most important coffee pest, the coffee berry borer (Hypothalemus hampei). We conducted field surveys and laboratory experiments to examine the impact of land‐use intensification on species richness and abundance of anoles and the capacity of anoles to reduce berry borer infestations in mainland and island coffee systems. Our results show that anoles significantly reduce coffee infestation rates in laboratory settings (Mexico, p = .03, F = 5.13 df = 1, 35; Puerto Rico, p = .014, F = 8.82, df = 1, 10) and are capable of consuming coffee berry borers in high abundance. Additionally, diversified agroecosystems bolster anole abundance, while high‐intensity practices, including the reduction of vegetation complexity and the application of agrochemicals were associated with reduced anole abundance. The results of this study provide supporting evidence of the positive impact of generalist predators on the control of crop pests in agricultural landscapes, and the role of diversified agroecosystems in sustaining both functionally diverse communities and crop production in tropical agroecosystems. 相似文献
997.
Relationships among multiple aspects of agriculture's environmental impact and productivity: a meta‐analysis to guide sustainable agriculture
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Richard N. German Catherine E. Thompson Tim G. Benton 《Biological reviews of the Cambridge Philosophical Society》2017,92(2):716-738
Given the pressures on land to produce ever more food, doing it ‘sustainably’ is growing in importance. However, ‘sustainable agriculture’ is complex to define, not least because agriculture impacts in many different ways and it is not clear how different aspects of sustainability may be in synergy or trade off against each other. We conducted a meta‐analysis to assess the relationships between multiple measures of sustainability using novel analytical methods, based around defining the efficiency frontier in the relationship between variables, as well as using correlation analysis. We define 20 grouped variables of agriculture's impact (e.g. on soil, greenhouse gas, water, biodiversity) and find evidence of both strong positive and negative correlations between them. Analysis based on the efficiency frontier suggests that trade‐offs can be ‘softened’ by exploiting the natural between‐study variation that arises from a combination of farming best practice and context. Nonetheless, the literature provides strong evidence of the relationship between yields and the negative externalities created by farming across a range of measures. 相似文献
998.
Tropical forests provide a wide range of ecosystem services (ES), and their continuous supply depends on efficient and effective management against deforestation and forest degradation. In Ecuador, indigenous communities are highly dependent on the forest and therefore on forest ES. However, there is a lack of knowledge about their demands concerning ES. In order to better understand how local and indigenous people use the forest and to facilitate its management, this study completed a spatially explicit assessment of ES using participatory mapping in the Sumaco Biosphere Reserve (Napo province, Central-Northern Ecuador). The Biosphere Reserve is suitable as a case study because it is a protected area with high land-use and population pressure and therefore requires the development and monitoring of management plans.First, semi-structured interviews were conducted with experts (n = 15) in order to identify the most important ES used by the communities in the study area. In a second step, members (n = 208) of 24 communities were asked to indicate on a 3-D map where they utilize the different ES (food, wood, water, tourism, hunting). The highlighted localities were digitized and then analyzed with statistical and GIS techniques. The results showed that the ES locations were not randomly distributed, but were most abundant four kilometers or less from roads. Spatial pattern analysis identified hotspots of ES provision, and the evaluation according to administrative units allowed us to identify five municipalities where demand for all assessed ES was high. In conclusion, the combination of participatory mapping of ES and GIS-based analysis can facilitate the identification of priority protection areas, provide guidance for developing specific forest management strategies, and also support monitoring systems to detect forest degradation. 相似文献
999.
The ‘Wild Seafood’ Provisioning Service (WSPS), on which commercial fisheries rely, is probably one of the best studied marine ecosystem services due to its economic relevance and because extensive information sources exist for assessment purposes. Yet, the indicators often proposed are not suitable to describe the capacity of the ecosystem to deliver the WSPS. Therefore this study proposes surplus production (SP), a well-established concept in fisheries science, as the basis to calculate the capacity of marine ecosystems to provide the WSPS. SP is defined as the difference between stock production (through recruitment and body growth) and losses through natural mortality. This is, therefore, the production of the stock that could be harvested sustainably without decreasing the biomass. To assess the sustainability of the exploitation of the WSPS we also developed an indicator for this based on SP and compared it to existing fisheries management indicators. When both SP-based indicators showed a decreasing trend, contrasting with an increasing trend in the existing fisheries management indicators, the calculation of the SP-based indicators was scrutinized revealing that the weighting of the stocks into an aggregated indicator, strongly determines the indicator values, even up to the point that the trend is reversed. The aggregated indicators based on SP-weighted stocks can be considered complementary to existing fisheries management indicators as the former accurately reflect the capacity of the commercial fish to provide the WSPS and the sustainability of the exploitation of this service. In contrast the existing fisheries management indicators primarily reflect the performance of management towards achieving fisheries-specific policy goals. 相似文献
1000.
This study proposes a novel regional sustainability assessment framework for integrated coastal zone management (ICZM). Various ICZM indicators have been developed, but their management insights are not always clear. Our framework integrates three separately developed approaches with an explicit reflection of stakeholders’ values: Satoumi (a Japanese concept of socio-ecological production landscapes, SEPLs), ecosystem services approach (ESA), and inclusive wealth (IW). We suggest that the integration of Satoumi, a uniquely Japanese concept, with the ESA and IW complements each other and increases the effectiveness of all three approaches when applied to ICZM and decision making. Satoumi describes the desired state of a coastal zone. The ESA translates Satoumi into IW and helps explain which changes to ecosystems contribute to the asset quality (i.e., shadow prices). As a sustainability indicator, IW differs from other ecological indicators because it comprises human, natural, and manufactured capital assets and incorporates shadow prices to weigh the contribution of each asset to the present value of social welfare. Shadow prices may capture the quality of capital assets in terms of how much people value them, and can therefore be a direct management target for realizing a desired coastal zone. We propose adding two sustainability criteria, desired state and strong sustainability, to the original IW to make it operational. The framework was tested in Japan’s Seto Inland Sea, and the results were analyzed in depth. Based on the outcomes, we discuss the insights for ICZM and future research. While Satoumi is a Japanese concept, the framework could be applied to other countries where similar SEPLs exist. 相似文献