Cosmology. Anthropic reasoning     

Livio M  Rees MJ 《Science (New York, N.Y.)》2005,309(5737):1022-1023

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Structural biology. Breaching the barrier     

Locher KP  Bass RB  Rees DC 《Science (New York, N.Y.)》2003,301(5633):603-604

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Biochemistry. Opening the molecular floodgates     

Gandhi CS  Rees DC 《Science (New York, N.Y.)》2008,321(5893):1166-1167

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Metapopulation dynamics, abundance, and distribution in a microecosystem     

A Gonzalez  JH Lawton  FS Gilbert  TM Blackburn  I Evans-Freke 《Science (New York, N.Y.)》1998,281(5385):2045-2047

The experimental fragmentation of landscapes of a natural ecosystem resulted in declines in the abundance and distribution of most species in the multispecies animal community inhabiting the landscapes and the extinction of many species. These declines caused the deterioration of the positive interspecific relation between local population abundance and distributional extent in this community. However, when patches were connected by habitat corridors, an immigration "rescue effect" arrested declines in both abundance and distribution and maintained the observed positive relation between them. These results demonstrate the importance of metapopulation dynamics and landscape connectivity for the persistence of populations in fragmented landscapes.  相似文献   

Carbon sequestration in a temperate grassland; management and climatic controls   总被引：1，自引：0，他引：1  

S. K. Jones    R. M. Rees    D. Kosmas    B. C. Ball  & U. M. Skiba 《Soil Use and Management》2006,22(2):132-142

Soil management practices that result in increased soil carbon (C) sequestration can make a valuable contribution to reducing the increase in atmospheric CO₂ concentrations. We studied the effect of poultry manure, cattle slurry, sewage sludge, NH₄NO₃ or urea on C cycling and sequestration in silage grass production. Soil respiration, net ecosystem exchange (NEE) and methane (CH₄) fluxes were measured with chambers, and soil samples were analysed for total C and dissolved organic C (DOC). Treatments were applied over 2 years and measurements were carried out over 3 years to assess possible residual effects. Organic fertilizer applications increased CO₂ loss through soil respiration but also enhanced soil C storage compared with mineral fertilizer. Cumulative soil respiration rates were highest in poultry manure treatments with 13.7 t C ha^?1 in 2003, corresponding to 1.6 times the control value, but no residual effect was seen. Soil respiration showed an exponential increase with temperature, and a bimodal relationship with soil moisture. The greatest NEE was observed on urea treatments (with a CO₂ uptake of ?4.4 g CO₂ m^?2 h^?1). Total C and DOC were significantly greater in manure treatments in the soil surface (0–10 cm). Of the C added in the manures, 27% of that in the sewage pellets, 32% of that in the cattle slurry and 39% of that in the poultry manure remained in the 0–10 cm soil layer at the end of the experiment. Mineral fertilizer treatments had only small C sequestration rates, although uncertainties were high. Expressed as global warming potentials, the benefits of increased C sequestration on poultry manure and sewage pellet treatments were outweighed by the additional losses of N₂O, particularly in the wet year 2002. Methane was emitted only for 2–3 days on cattle slurry treatments, but the magnitudes of fluxes were negligible compared with C losses by soil respiration.  相似文献   

Tillage erosion within potato production systems in Atlantic Canada: I. Measurement of tillage translocation by implements used in seedbed preparation     

K.H.D. Tiessen  G.R. Mehuys  D.A. Lobb  H.W. Rees 《Soil & Tillage Research》2007,95(1-2):308-319

In Canada, there is growing acceptance that tillage erosion is a serious form of soil degradation and a threat to the sustainability of agriculture across the country. To date, the potential risk for tillage erosion within potato production systems has not been investigated. The objective of this study was to generate tillage translocation values for primary and secondary tillage implements common to seedbed preparation within conventionally and conservation tilled potato production systems in Atlantic Canada. Tillage translocation was measured for each implement by labelling a plot of soil with a tracer. The tracer redistribution along the path of tillage was used to generate a summation curve to calculate mean soil movement in the direction of tillage. The results show that each primary and secondary tillage operation moved vast quantities of soil and is potentially erosive. Maximum displacement distances were considerably larger in this project than those reported in previous studies looking at tillage erosion by primary and/or secondary tillage implements. All four tillage implements tested moved soil at least 3 m, with the greatest translocated distances (5.6 m) observed for the chisel plough (CP) and vibrashank (VS). The mass of translocated soil (T_M) was greatest for the CP, followed by the mouldboard plough (MP), VS and offset disc (OD). In addition, compared to travelling downslope, the upslope speed of tillage was reduced by 38%, 21%, 32% and 12% for the MP, CP, OD and VS, respectively, while the depth of tillage was reduced by 6%, 5%, 35% and 2%, respectively. It is apparent that conservation tillage implements (the CP is generally promoted to reduce water erosion in Atlantic Canada) and secondary tillage implements (OD and VS) can move as much soil as conventional tillage implements such as the mouldboard plough, and must be considered when developing plans to reduce soil erosion within potato fields in Atlantic Canada.  相似文献   

Nitrous oxide and methane emissions from a vetch cropping season are changed by long-term tillage practices in a Mediterranean agroecosystem     

Angela Tellez-Rio  Sonia García-Marco  Mariela Navas  Emilia López-Solanilla  Robert M. Rees  Jose Luis Tenorio  Antonio Vallejo 《Biology and Fertility of Soils》2015,51(1):77-88

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Anthropogenic injury and site fidelity in Maldivian whale sharks (Rhincodon typus)     

Harriet L. Allen  Bryce D. Stewart  Colin J. McClean  James Hancock  Richard Rees 《水产资源保护:海洋与淡水生态系统》2021,31(6):1429-1442

1. Whale sharks collect in predictable seasonal aggregations across the tropics. South Ari Atoll in the Maldives is one of a few aggregation sites where whale sharks can be encountered year-round. Here, areas with high levels of tourism-related boating traffic overlap with the whale shark hotspot, increasing the probability of anthropogenic injury. Whale sharks have been reported to remain faithful to this aggregation site following injury, despite the costs of injury and the risk of re-injury. However, the impacts of injury on site fidelity and residency behaviour are not fully understood.
2. Encounter data on individual sharks from the Maldives Whale Shark Research Programme database (2006–2018) were analysed to assess the relationship between injury and site fidelity in whale sharks. There was no difference in geographic site use, with injured and non-injured individuals being encountered in the same areas. However, there were differences in residency timings: injured resident whale sharks (individuals repeatedly encountered over 6 months or longer) spent significantly more time at the atoll and less time absent, and were seen more consistently than non-injured residents. Increased residency duration, return rate and number of residency periods correlated with increasing injury number.
3. These differences in behaviour imply a cost to injury, with whale sharks potentially remaining at this site to recover. With boat traffic being concentrated at the aggregation site, injured sharks may be more vulnerable to further injury. Alternatively, these individuals may remain at the atoll despite injury because the benefits gained from this area outweigh the potential costs, with more resident individuals facing greater exposure to anthropogenic threats. These findings highlight the importance of this location and emphasize the need for improved management of anthropogenic activities, particularly boating traffic, at aggregation hotspots to reduce injury rates and any subsequent impacts on behaviour and fitness.

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Serological response of vaccinated sheep after challenge with Corynebacterium pseudotuberculosis     

SS SUTHERLAND  TM ELLIS  MJ PATON  AR MERCY 《Australian veterinary journal》1992,69(7):168-169

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Use of magnetic particles to improve the diagnosis of sheep-associated malignant catarrhal fever by polymerase chain reaction     

TM ELLIS  AM MASTERS 《Australian veterinary journal》1997,75(7):520-521

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