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151.
Alan E. Haberstock Henry G. Nichols Mark P. DesMeules Jed Wright Jon M. Christensen Daniel H. Hudnut 《Journal of the American Water Resources Association》2000,36(6):1271-1286
ABSTRACT: Successful restoration of declining anadromous species is dependent upon effective riparian buffer zone management. Natural resource managers, policy developers and local conservation groups require science‐based information concerning the width at which a given buffer will be effective for its stated purpose. This paper summarizes a method developed in 1999 to determine effective riparian buffer widths for Atlantic salmon habitat protection as part of the Atlantic Salmon Conservation Plan for Seven Maine Rivers. A major assumption of the method is that no two buffers are alike with respect to their effectiveness and that various buffer characteristics dictate the required width for a given level of effectiveness. The method uses a predictive model that generates suggested riparian buffer widths as a function of specific, measurable buffer characteristics (such as slope, soil characteristics, and plant community structure and density) that affect buffer function. The method utilizes a variable‐width, two‐zone approach and specifies land uses that are consistent with desired buffer function within the two zones. 相似文献
152.
The case described in this article regards 4.7 km of beach in Ferring, situated approx. 5 km south to the mouth of the Limfjord
strait on the west coast of Denmark. In 2005, this section of the beach was nourished with 721,000 m3 of material in order to protect backshore properties, natural heritages and the recreational value of the beach. After the
nourishment, the beach was monitored by levelling profiles on four dates to monitor and track the evolution of the nourished
material. Furthermore, laboratory tests involving different gradations of nourishment material are shown which indicate solutions
to different kinds of coastal protection strategies, estimate the time in between two nourishments and evaluate the cost of
maintaining a beach with a high recreational value for the public. 相似文献
153.
Clarifying the role of fire in the deciduous forests of eastern North America: reply to Matlack
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154.
Spatial patterns of carbon,biodiversity, deforestation threat,and REDD+ projects in Indonesia
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Josil P. Murray Richard Grenyer Sven Wunder Niels Raes Julia P.G. Jones 《Conservation biology》2015,29(5):1434-1445
There are concerns that Reduced Emissions from Deforestation and forest Degradation (REDD+) may fail to deliver potential biodiversity cobenefits if it is focused on high carbon areas. We explored the spatial overlaps between carbon stocks, biodiversity, projected deforestation threats, and the location of REDD+ projects in Indonesia, a tropical country at the forefront of REDD+ development. For biodiversity, we assembled data on the distribution of terrestrial vertebrates (ranges of amphibians, mammals, birds, reptiles) and plants (species distribution models for 8 families). We then investigated congruence between different measures of biodiversity richness and carbon stocks at the national and subnational scales. Finally, we mapped active REDD+ projects and investigated the carbon density and potential biodiversity richness and modeled deforestation pressures within these forests relative to protected areas and unprotected forests. There was little internal overlap among the different hotspots (richest 10% of cells) of species richness. There was also no consistent spatial congruence between carbon stocks and the biodiversity measures: a weak negative correlation at the national scale masked highly variable and nonlinear relationships island by island. Current REDD+ projects were preferentially located in areas with higher total species richness and threatened species richness but lower carbon densities than protected areas and unprotected forests. Although a quarter of the total area of these REDD+ projects is under relatively high deforestation pressure, the majority of the REDD+ area is not. In Indonesia at least, first‐generation REDD+ projects are located where they are likely to deliver biodiversity benefits. However, if REDD+ is to deliver additional gains for climate and biodiversity, projects will need to focus on forests with the highest threat to deforestation, which will have cost implications for future REDD+ implementation. 相似文献
155.
Alan Watson Steve Martin Neal Christensen Gregg Fauth Dan Williams 《Environmental management》2015,56(3):653-663
156.
Abigail Bennett Xavier Basurto John Virdin Xinyan Lin Samantha J. Betances Martin D. Smith Edward H. Allison Barbara A. Best Kelly D. Brownell Lisa M. Campbell Christopher D. Golden Elizabeth Havice Christina C. Hicks Peter J. Jacques Kristin Kleisner Niels Lindquist Rafaella Lobo Grant D. Murray Michelle Nowlin Pawan G. Patil Douglas N. Rader Stephen E. Roady Shakuntala H. Thilsted Sarah Zoubek 《Ambio》2021,50(5):981
The international development community is off-track from meeting targets for alleviating global malnutrition. Meanwhile, there is growing consensus across scientific disciplines that fish plays a crucial role in food and nutrition security. However, this ‘fish as food’ perspective has yet to translate into policy and development funding priorities. We argue that the traditional framing of fish as a natural resource emphasizes economic development and biodiversity conservation objectives, whereas situating fish within a food systems perspective can lead to innovative policies and investments that promote nutrition-sensitive and socially equitable capture fisheries and aquaculture. This paper highlights four pillars of research needs and policy directions toward this end. Ultimately, recognizing and working to enhance the role of fish in alleviating hunger and malnutrition can provide an additional long-term development incentive, beyond revenue generation and biodiversity conservation, for governments, international development organizations, and society more broadly to invest in the sustainability of capture fisheries and aquaculture.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01451-4) contains supplementary material, which is available to authorized users. 相似文献
157.
Lotte Hatt Katarina Ravn Line Dahl Jeppesen Bolette Hestbek Nicolaisen Inga Baasch Christensen Ripudaman Singh Palle Schelde Simon Horsholt Thomsen Rikke Christensen Marianne Sinding Laura Vase Marianne Oestergaard Marie Bender Ruggard Hanne S. Jensen Helle Mogensen Niels Uldbjerg Naja Becher Sara Markholt Puk Sandager Lars Henning Pedersen Ida Vogel 《黑龙江环境通报》2023,43(7):854-864
Objectives
We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS) and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT).Material and Methods
Study 1: Women (N = 92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Samples were analyzed with chromosomal microarray (CMA). Study 2: Women (N = 282) who accepted cfNIPT were recruited for cbNIPT. cfNIPT was analyzed using sequencing and cbNIPT by CMA.Results
Study 1: cbNIPT detected all aberrations (32/32) found in CVS: trisomies 13, 18 and 21 (23/23), pathogenic copy number variations (CNVs) (6/6) and sex chromosome aberrations (3/3). cbNIPT detected 3/8 cases of mosaicism in the placenta. Study 2: cbNIPT detected all trisomies found with cfNIPT (6/6) and had no false positive (0/246). One of the three CNVs called by cbNIPT was confirmed by CVS but was undetected by cfNIPT, two were false positives. cbNIPT detected mosaicism in five samples, of which two were not detected by cfNIPT. cbNIPT failed in 7.8% compared to 2.8% in cfNIPT.Conclusion
Circulating trophoblasts in the maternal circulation provide the potential of screening for aneuploidies and pathogenic CNVs covering the entire fetal genome. 相似文献158.
The number of environmental impact assessment (EIA) screenings in Denmark has increased dramatically since 2000. This is a consequence of increased pig production as well as the concentration of production on larger farms. In the same period, EIA rules have developed primarily due to an increased focus on the protection of groundwater and Natura 2000 sites. In particular, the implementation of Natura 2000 in Danish legislation has increased the demands on many farms. In its rulings on appealed cases, the Nature Protection Board of Appeal has strengthened its demands, and this is mirrored in screening practices. In this paper, the demands formulated in the guidelines of local authorities were analysed in order to investigate how the protection of groundwater, coastal waters, lakes and Natura 2000 sites develops through EIA screening. It is concluded that the level of protection has improved, and that the main cause for this is not EIA regulations as such, but the positive role which the implementation of the Natura 2000 objectives has played in this development. However, it was also found that the formulation of demands varies greatly between the counties, thus often resulting in ambiguity and leaving room for quite different practices in different counties. 相似文献
159.
Runoff coefficients are usually considered in isolation for each drainage area with resulting large uncertainties in the areas
and coefficients. Accurate areas and coefficients are obtained here by optimizing runoff coefficients for characteristic Geographic
Information Systems (GIS) subareas within each drainage area so that the resulting runoff coefficients of each drainage area
are consistent with those obtained from runoff and rainfall volumes. Lack of fit can indicate that the ArcGIS information
is inaccurate or more likely, that the drainage area needs adjustment. Results for 18 drainage areas in Milwaukee, WI for
2000–2004 indicate runoff coefficients ranging from 0.123 for a mostly residential area to 0.679 for a freeway-related land,
with a standard error of 0.047. Optimized runoff coefficients are necessary input parameters for monitoring, and for the analysis
and design of in situ stormwater unit operations and processes for the control of both urban runoff quantity and quality. 相似文献
160.
Ceri J. Vincent Niels E. Poulsen Zeng Rongshu Dai Shifeng Li Mingyuan Ding Guosheng 《International Journal of Greenhouse Gas Control》2011,5(3):598-603
The storage potential of selected sites within the Bohai Basin was assessed for the COACH project. The Gangdong oilfield is considered to have a small potential storage capacity (23 Mt) and to be possibly suitable for an enhanced oil recovery or small-scale storage pilot rather than large-scale storage. The Shengli oilfield province is considered to have a great potential storage capacity (472 Mt in eight selected fields), however, these fields, like those of the Gangdong oilfield province, are compartmentalised by faulting and stratigraphy and likely to be quite challenging for injection. Unmineable coal seams in the Kailuan mining area were also considered for storage, the estimated capacity is 504 Gt adsorbed onto the coal and 38,100 Mt void storage capacity. However, the coals have low porosity and permeability, so they would be expected to have poor injectivity. This is also an active mining area and so any storage site would have to be chosen carefully to avoid affecting future energy resources. The Huimin sub-basin within the Jiyang Depression was identified for consideration as an aquifer storage site; the Guantao Formation has good porosity and permeability in this region, and the regional-level storage capacity of these areas was estimated to be 0.7 Gt. The aquifers in the Huimin sub-basin appear promising for storage, however, less data are available than for the oilfields and the sealing formations are not directly proven to trap buoyant fluids, though in adjacent oilfield in the Shengli oilfield province, the Minghuazhen Formation forms a regional seal for the Guantao Formation. 相似文献