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151.
152.
Divya Narain Laura J. Sonter Alex Mark Lechner James E. M. Watson Jeremy S. Simmonds Martine Maron 《Conservation biology》2023,37(4):e14095
Infrastructure development is a major driver of biodiversity loss globally. With upward of US$2.5 trillion in annual investments in infrastructure, the financial sector indirectly drives this biodiversity loss. At the same time, biodiversity safeguards (project-level biodiversity impact mitigation requirements) of infrastructure financiers can help limit this damage. The coverage and harmonization of biodiversity safeguards are important factors in their effectiveness and therefore warrant scrutiny. It is equally important to examine the extent to which these safeguards align with best-practice principles for biodiversity impact mitigation outlined in international policies, such as that of the International Union for Conservation of Nature. We assessed the biodiversity safeguards of public development banks and development finance institutions for coverage, harmonization, and alignment with best practice. We used Institute of New Structural Economics and Agence Française de Développement's global database to identify development banks that invest in high-biodiversity-footprint infrastructure and have over US$500 million in assets. Of the 155 banks, 42% (n = 65) had biodiversity safeguards. Of the existing safeguards, 86% (56 of 65) were harmonized with International Finance Corporation (IFC) Performance Standard 6 (PS6). The IFC PS6 (and by extension the 56 safeguard policies harmonized with it) had high alignment with international best practice in biodiversity impact mitigation, whereas the remaining 8 exhibited partial alignment, incorporating few principles that clarify the conditions for effective biodiversity offsetting. Given their dual role in setting benchmarks and leveraging private finance, infrastructure financiers in development finance need to adopt best-practice biodiversity safeguards if the tide of global biodiversity loss is to be stemmed. The IFC PS6, if strengthened, can act as a useful template for other financier safeguards. The high degree of harmonization among safeguards is promising, pointing to a potential for diffusion of practices. 相似文献
153.
Nicole Basenback Jeremy M. Testa Chunqi Shen 《Journal of the American Water Resources Association》2023,59(2):429-445
The effects of nutrient loading on estuaries are well studied, given the multitude of negative water quality and ecosystem effects that have been attributed to excess nitrogen and phosphorus. A current gap in this knowledge involves the sensitivity of seasonal cycles of estuarine biogeochemical processes to direct (warming) and indirect influences (nutrient load timing) of climate change. We used a coupled hydrologic–biogeochemical model to investigate changes in the phenology of hypoxia and related biogeochemical processes in Chesapeake Bay under three different hydrologic regimes. Shifts to earlier nutrient load timing during idealized simulations reduced the overall annual hypoxic volume, resulting from discernable, but relatively small reductions in phytoplankton biomass and both sediment and water-column respiration. Simulated increases in water temperature caused an increase in spring/early summer hypoxic volume associated with elevated respiration rates, but an associated exhaustion of organic matter in the early summer caused a decrease in late summer/fall hypoxic volume due to lowered respiration. Warming effects on hypoxia were larger than nutrient timing effects in scenarios where warming was restricted to spring and when it was applied to all months of the year. These idealized simulations begin the process of understanding the potential impacts of future climatic changes in the seasonal timing of key biogeochemical processes associated with eutrophication. 相似文献
154.
Sonter Laura J. Gordon Ascelin Archibald Carla Simmonds Jeremy S. Ward Michelle Metzger Jean Paul Rhodes Jonathan R. Maron Martine 《Ambio》2020,49(4):892-902
Ambio - Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most... 相似文献
155.
Bao Ha Leili Zamini Jeremy Monn Samuel Njoroge Laban Thimo Maria Ondeti 《Journal of environmental science and health. Part. B》2018,53(3):161-170
Water quality assessment was conducted on the Ruiru River, a tributary of an important tropical river system in Kenya, to determine baseline river conditions for studies on the aquatic fate of N-methyl carbamate (NMC) pesticides. Measurements were taken at the end of the long rainy season in early June 2013. Concentrations of copper (0.21–1.51 ppm), nitrates (2.28–4.89 ppm) and phosphates (0.01–0.50 ppm) were detected at higher values than in uncontaminated waters, and attributed to surface runoff from agricultural activity in the surrounding area. Concentrations of dissolved oxygen (8–10 ppm), ammonia (0.02–0.22 ppm) and phenols (0.19–0.83 ppm) were found to lie within normal ranges. The Ruiru River was found to be slightly basic (pH 7.08–7.70) with a temperature of 17.8–21.2°C. The half-life values for hydrolysis of three NMC pesticides (carbofuran, carbaryl and propoxur) used in the area were measured under laboratory conditions, revealing that rates of decay were influenced by the electronic nature of the NMCs. The hydrolysis half-lives at pH 9 and 18°C decreased in the order carbofuran (57.8 h) > propoxur (38.5 h) > carbaryl (19.3 h). In general, a decrease in the electron density of the NMC aromatic ring increases the acidity of the N-bound proton removed in the rate-limiting step of the hydrolysis mechanism. Our results are consistent with this prediction, and the most electron-poor NMC (carbaryl) hydrolyzed fastest, while the most electron-rich NMC (carbofuran) hydrolyzed slowest. Results from this study should provide baseline data for future studies on NMC pesticide chemical fate in the Ruiru River and similar tropical water systems. 相似文献
156.
Sather ME Mathew J Nguyen N Lay J Golod G Vet R Cotie J Hertel T Aaboe E Callison R Adam J Keese D Freise J Hathcoat A Sakizzie B King M Lee C Oliva S San Miguel G Crow L Geasland F 《Journal of environmental monitoring : JEM》2008,10(11):1319-1325
Ambient ammonia monitoring using Ogawa passive samplers was conducted in the Four Corners area and eastern Oklahoma, USA during 2007. The resulting data will be useful in the multipollutant management of ozone, nitrogen oxides, and visibility (atmospheric regional haze) in the Four Corners area, an area with growing oil/gas production and increasing coal-based power plant construction. The passive monitoring data also add new ambient ammonia concentration information for the U.S. and will be useful to scientists involved in present and future visibility modeling exercises. Three week integrated passive ammonia samples were taken at five sites in the Four Corners area and two sites in eastern Oklahoma from December, 2006 through December, 2007 (January, 2008 for two sites). Results show significantly higher regional background ammonia concentrations in eastern Oklahoma (1.8 parts per billion (ppb) arithmetic mean) compared to the Four Corners area (0.2 ppb arithmetic mean). Annual mean ammonia concentrations for all Four Corners area sites for the 2007 study ranged from 0.2 ppb to 1.5 ppb. Peak ambient ammonia concentrations occurred in the spring and summer in both areas. The passive samplers deployed at the Stilwell, Oklahoma site compared favorably with other passive samplers and a continuous ammonia monitoring instrument. 相似文献
157.
Most agricultural information is reported by government sources on a state or county basis. The purpose of this study was
to demonstrate use of geospatial data, the 2002 Agricultural Cropland Data Layer (CDL) for the mid-Atlantic region, to characterize
agricultural, environmental, and other scientific parameters for the Chincoteague Bay subbasin using geographic information
systems. This study demonstrated that agriculture can be characterized accurately on subbasin and subwatershed bases, thus
complimenting various assessment technologies. Approximately 28% of the dry land of the subbasin was cropland. Field corn
was the largest crop. Soybeans, either singly or double-cropped with wheat, were the second most predominant crop. Although
the subbasin is relatively small, cropping practices in the northern part were different from those in the southern portion.
Other crops, such as fresh vegetables and vegetables grown for processing, were less than 10% of the total cropland. A conservative
approximation of the total pesticide usage in the subbasin in 2002 was over 277,000 lbs of active ingredients. Herbicides
represented the most frequently used pesticides in the subbasin, both in number (17) and in total active ingredients (over
261,000 lbs). Ten insecticides predominated in the watershed, while only small quantities of three fungicides were used. Total
pesticide usage and intensity were estimated using the CDL. Nutrient inputs to cropland from animal manure, chemical fertilizer,
and atmospheric deposition were modeled at over 30 million pounds of nitrogen and over 7 million pounds of phosphorous. Crops
under conservation tillage had the largest input of both nutrients. 相似文献
158.
159.
Warren Y. Brockelman Ulrich Reichard Uthai Treesucon Jeremy J. Raemaekers 《Behavioral ecology and sociobiology》1998,42(5):329-339
We report observations on reproduction, natal dispersal, pair formation, and group structure based on longitudinal observations
of several white-handed gibbon (Hylobates lar) groups spanning 18 years. Our observations are at odds with the traditional view that gibbons live in nuclear family groups
consisting of a pair of adults and their offspring, and that parents exclude young from the family territory when they reach
adult size. In the relatively dense Khao Yai study population, dispersing young usually obtain mates by replacing adults in
existing territories, which creates non-nuclear families. Six subadults, five males and one female, matured and dispersed
at an average age of 10 years, or about 2 years after reaching adult size. Average natal dispersal distance was 710 m, or
between one and two territories away. At least two dispersing males replaced adults in neighboring groups. In one case, forcible
displacement of the resident male resulted in a group which included a young juvenile presumably fathered by the previous
male, two younger juveniles (probably brothers) from the new male's original group, and (later) offspring of the new pair.
Social relations within this heterogeneous group remained harmonious: the adults groomed all the young and play occurred between
all preadult members. In only two out of a total of seven cases of dispersal seen did two subadults pair and disperse into
new territorial space. Nonreproducing subadults which delay dispersal may be tolerated by the adults provided that they contribute
benefits to the adults or their offspring. Possible benefits include behaviors such as grooming, social play with juveniles,
and support of the adult male in defending the territory. Delayed dispersal is probably advantageous in a saturated environment
where there is no room for floaters, but subadults may also gain indirect fitness benefits by aiding siblings and other relatives.
Received: 24 January 1997 / Accepted after revision: 12 January 1998 相似文献
160.
During the last two decades, the importance of sulphur dioxide as a pollutant has moved away from its association with suspended particulate matter, to it being a precursor of SO
4
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aerosol (acidic e.g. sulphuric acid, or neutralised e.g. ammonium sulphate). Co-located concentration data of sulphur dioxide and SO
4
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, at nine monitoring sites situated in predominantly rural areas in the United Kingdom, collected over the time period 1979–1995, have been analysed. The time series for both species are discussed for the sites. Further analysis has shown that there is a degree of correlation between sulphur dioxide and SO
4
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for most of the sites considered. This correlation is of approximately the same level for most of the sites taken independently and together, and in most cases the slopes and intercepts associated with the simple empirical model equations arising from the correlation analysis, are of the same order of magnitude. The implementation of these site-dependent model equations within dispersion models for the prediction of the concentration of airborne sulphate aerosol from knowledge of sulphur dioxide concentration is discussed. Furthermore, the correlation analysis revealed the influence of transported sulphate aerosol on the local concentration, especially during high concentration episodes. 相似文献