Effect of fertilization rate and ploughing time on nitrous oxide emissions in a long-term cereal trail in south east Norway     

Shahid Nadeem  Trond Børresen  Peter Dörsch 《Biology and Fertility of Soils》2015,51(3):353-365

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Setting the net lower: A potential low-cost mitigation method to reduce cetacean bycatch in drift gillnet fisheries     

Jeremy J. Kiszka  Muhammad Moazzam  Germain Boussarie  Umair Shahid  Babar Khan  Rab Nawaz 《水产资源保护:海洋与淡水生态系统》2021,31(11):3111-3119

1. Bycatch is the most significant threat to marine megafauna (sea turtles, marine mammals, elasmobranchs, seabirds) worldwide, and the leading cause of the decline of several cetacean species. The bycatch issue in the Indian Ocean is poorly understood, but high bycatch levels in gillnet fisheries have been documented for the past two decades, in both small-scale and semi-industrial fisheries. Unfortunately, methods to reduce bycatch are often unavailable, financially non-viable or socially unacceptable to fishermen.
2. Using a network of trained boat captains in the tuna drift gillnet fishery in the Arabian Sea, targeted catch and bycatch data were collected from 2013 to 2017 off the coast of Pakistan (northern Indian Ocean). Two fishing methods using multifilament gillnets were used: surface deployment and subsurface deployment (i.e. headline of net set below 2 m depth).
3. Predicted catch rates for targeted species did not differ significantly between the two fishing practices, although a drop in tuna (6.2%) and tuna-like (10.9%) species captures was recorded in subsurface sets. The probability of cetacean bycatch, however, was 78.5% lower in subsurface than in surface sets.
4. Cetacean bycatch in tuna drift gillnet fisheries has the potential to be significantly reduced at a relatively low cost for fishers. However, further research with an appropriate sampling design and a large sample size is required to confirm the efficacy of the proposed mitigation method. The acceptability and adoption of subsurface setting by fishers also needs to be further investigated. Despite some limitations, this preliminary study also highlights the importance of crew-based observer data as an alternative source of data when observers cannot be deployed on fishing vessels.

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Species loss and aboveground carbon storage in a tropical forest   总被引：1，自引：0，他引：1  

Bunker DE  Declerck F  Bradford JC  Colwell RK  Perfecto I  Phillips OL  Sankaran M  Naeem S 《Science (New York, N.Y.)》2005,310(5750):1029-1031

Tropical forest biodiversity is declining, but the resulting effects on key ecosystem services, such as carbon storage and sequestration, remain unknown. We assessed the influence of the loss of tropical tree species on carbon storage by simulating 18 possible extinction scenarios within a well-studied 50-hectare tropical forest plot in Panama, which contains 227 tree species. Among extinction scenarios, aboveground carbon stocks varied by more than 600%, and biological insurance varied by more than 400%. These results indicate that future carbon storage in tropical forests will be influenced strongly by future species composition.  相似文献   

Independently evolved virulence effectors converge onto hubs in a plant immune system network     

Mukhtar MS  Carvunis AR  Dreze M  Epple P  Steinbrenner J  Moore J  Tasan M  Galli M  Hao T  Nishimura MT  Pevzner SJ  Donovan SE  Ghamsari L  Santhanam B  Romero V  Poulin MM  Gebreab F  Gutierrez BJ  Tam S  Monachello D  Boxem M  Harbort CJ  McDonald N  Gai L  Chen H  He Y;European Union Effectoromics Consortium  Vandenhaute J  Roth FP  Hill DE  Ecker JR  Vidal M  Beynon J  Braun P  Dangl JL 《Science (New York, N.Y.)》2011,333(6042):596-601

Plants generate effective responses to infection by recognizing both conserved and variable pathogen-encoded molecules. Pathogens deploy virulence effector proteins into host cells, where they interact physically with host proteins to modulate defense. We generated an interaction network of plant-pathogen effectors from two pathogens spanning the eukaryote-eubacteria divergence, three classes of Arabidopsis immune system proteins, and ~8000 other Arabidopsis proteins. We noted convergence of effectors onto highly interconnected host proteins and indirect, rather than direct, connections between effectors and plant immune receptors. We demonstrated plant immune system functions for 15 of 17 tested host proteins that interact with effectors from both pathogens. Thus, pathogens from different kingdoms deploy independently evolved virulence proteins that interact with a limited set of highly connected cellular hubs to facilitate their diverse life-cycle strategies.  相似文献