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491.
Ecosystem-based Management (EBM) is an approach that includes different management priorities and requires a balance between
anthropogenic and ecological resource demands. Indicators can be used to monitor ecosystem status and trends, and assess whether
projects and/or programs are leading to the achievement of management goals. As such, the careful selection of a suite of
indicators is a crucial exercise. In this paper we describe an indicator evaluation and selection process designed to support
the EBM approach in Puget Sound. The first step in this process was the development of a general framework for selecting indicators.
The framework, designed to transparently include both scientific and policy considerations into the selection and evaluation
process, was developed and then utilized in the organization and determination of a preliminary set of indicators. Next, the
indicators were assessed against a set of nineteen distinct criteria that describe the model characteristics of an indicator.
A literature review was performed for each indicator to determine the extent to which it satisfied each of the evaluation
criteria. The result of each literature review was summarized in a numerical matrix, allowing comparison, and demonstrating
the extent of scientific reliability. Finally, an approach for ranking indicators was developed to explore the effects of
intended purpose on indicator selection. We identified several sets of scientifically valid and policy-relevant indicators
that included metrics such as annual-7 day low flow and water system reliability, which are supportive of the EBM approach
in the Puget Sound. 相似文献
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L. P. Agulova A. V. Andreevskikh N. P. Bol’shakova L. B. Kravchenko N. G. Suchkova N. S. Moskvitina 《Russian Journal of Ecology》2010,41(6):506-512
The ratios between individuals with different signs of motor asymmetry (right-pawed, left-pawed, and ambidextrous) were estimated
in two urban populations of striped field mice. Right-pawed mice were prevailing in both populations. An increase in the stress
of regulatory system (stress index) in mice from these populations was accompanied by a shift of the asymmetry profile towards
a greater proportion of left-pawed mice. The ratio between the numbers of right-pawed and non-right-pawed animals varied with
time with a period close to that of the population dynamics. Apparently, the changes in the asymmetry profiles reflected population
rearrangement: dominance of animals with a specific set of physiological, ecological, and behavioral characteristics gave
way to an increased proportion of animals with a different set of characteristics. Qualitative differences between right-
and left-pawed animals are evidenced by the specific characteristics of behavior and humoral immunity found in animals differing
in motor lateralization. 相似文献
494.
Ecological features and species composition of leeches were studied in 25 water bodies located in the city of Yekaterinburg and its vicinity. Specific features of their occurrence and distribution in water bodies of various types were analyzed. Dominant, mass, common, and rare species were distinguished. 相似文献
495.
V. V. Martemyanov S. A. Bakhvalov M. J. Rantala I. M. Dubovskiy E. E. Shul’ts I. A. Belousova A. G. Strel’nikov V. V. Glupov 《Russian Journal of Ecology》2009,40(6):434-439
The effects of birch resistance induced by its artificial defoliation on the development of gypsy moth larvae and their sensitivity
to viral infection and on the state of the antioxidant and detoxification systems of the insect midgut were studied. The dynamics
of larval body weight; larval mortality and its etiology; glutathione-S-transferase (GT), nonspecific esterase (NE), and catalase
(CAT) activities; and the ratio between the concentrations of oxidized and reduced thiol-containing compounds (RSSR/RSH) were
estimated. In larvae feeding on the leaves of a previously defoliated plant, body weight was decreased, NE was inhibited,
and the RSSR/RSH ratio was increased. 相似文献
496.
Long-term (≥20 years) application of fertilizers and straw return enhances soil carbon storage: a meta-analysis 总被引:2,自引:0,他引:2
Yu’e Li Shengwei Shi Muhammad Ahmed Waqas Xiaoxia Zhou Jianling Li Yunfan Wan Xiaobo Qin Qingzhu Gao Shuo Liu Andreas Wilkes 《Mitigation and Adaptation Strategies for Global Change》2018,23(4):603-619
Increasing soil carbon (C) storage is crucial to addressing climate change and ensuring food security. The C sequestration potential of the world’s cropland soil is 0.4–0.8 Pg soil C year?1, which may be achieved through the adoption of recommended management practices (RMPs), including fertilizer management. This study aimed to quantitatively evaluate the influence of long-term application of different fertilizers and straw retention on soil organic carbon (SOC) storage, to compare the calculated response ratios with Intergovernmental Panel on Climate Change (IPCC)-recommended default relative stock change factors, and to propose recommendations for enhancing SOC sequestration. The meta-analysis indicated that the long-term application of chemical fertilizers (CF), organic fertilizers (OF), combined chemical and organic fertilizers (CFOF), and straw return (SR) significantly enhanced the SOC storage. Response ratios varied significantly (p < 0.05) across different fertilization measures and climatic zones, and was sensitive to the initial SOC content. The mean response ratio was 0.94 for no fertilizer (NF), 1.08 for CF, 1.48 for OF, 1.38 for CFOF, and 1.28 for SR. When IPCC default values for response ratios were applied, SOC storage with OF and CFOF treatments in warm temperate regions with a dry climate was underestimated by 26%, and in the cool temperate region with a moist climate was overestimated by 25% (p < 0.05). Analysis showed that sustained application of organic fertilizers and straw return could be a beneficial measures to mitigate climate change and ensure food security in China. Our findings highlight the importance of deriving SOC stock change factors for a detailed classification of cropland by fertilizer management, climate, and soil types in order to more accurately reflect the effects of policy measures. 相似文献
497.
A novel humic acid-based polycarboxylic-type (HAP) dispersant for coal–water slurry (CWS) was successfully synthesized in aqueous solution from the copolymerization of HA, acrylic acid and maleic acid. The structure of HAP was characterized by Fourier transform infrared (FTIR), thermogravimetry (TG) and 1H NMR. With HAP as a dispersant for Linfen coal slurry, the effects of the mass ratio of HA and monomer, initiator concentration, reaction temperature and reaction time on the HAP dispersant performance were discussed by examining the apparent viscosity of CWS. The results showed that CWS prepared withHAP dispersant performed excellent dispersity and stability. When the dosage of HAP was up to 0.5 wt.%, the apparent viscosity of CWS was 505 mPa·s. Experiments on the stability of CWS containing 0.5 wt.% HAP demonstrated that the penetration ratio reached 85.45 % after 96 h, which was higher by 12.87 % than that of CWS prepared with HA. And the CWS produced with HAP had lower dewatering rate within the storage time, which was less 1.85 % than that of CWS with HA when the storage time was 72 h. Furthermore, the maximum coal content of CWS with 0.5 wt.% HAP may reached 70 wt.%. This work found a new route for utilizing humic acid and enlarged the selecting range of the dispersant for CWS. It has a positive significance for protection of environment. 相似文献
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