PhD reform

This week we will be discussing several recent articles calling for reform of the PhD system, which you can find here:

http://dx.doi.org/10.1038/472261a
http://dx.doi.org/10.1038/472276a
http://dx.doi.org/10.1038/472280a
http://dx.doi.org/10.1371/journal.pone.0036307
http://www.scientists.org.nz/files/journal/2012-69/NZSR_69-2.pdf (pp.30-39)

One of our members also suggested watching this video about broader issues of educational reform:

http://www.youtube.com/watch?v=zDZFcDGpL4U

Please feel free to discuss these articles using the comments section of this blog. All relevant contributions are welcome.

Using existing scientific capacity to set targets for ecosystem-based management: A Puget Sound case study

Samhouri¸ J.

Even though it has been more than 20 years since its creation, there is no consensus on the definition of Ecosystem Management (EM) or Ecosystem Based Management (EBM) yet. This has led to scientists and ecosystem managers giving this type of management their own interpretation and implementation (Grumbine, 1994; Simberloff, 1994).

Fundamentally, ecosystem management is a modern, holistic method of managing a biological system at an ecosystem level that explicitly considers humans as part of that system (Grumbine, 1994; Simberloff, 1994). This approach is promoted by major international organizations (i.e. UNEP, IUCN, and others) as the best solution for the current biodiversity loss crisis.

A frequent problem with the EBM approach is a lack of reference levels and indicators (values or range of values) to determine the current and desirable state of an ecosystem when it comes to managing it (Samhouri et al., 2011). Moreover, EBM relies on terms as ‘sustainability’ and ‘ecosystem health’, concepts whose meaning and measurement are still under debate (Simberloff, 1994). Consequently, it is very difficult to determine the success of an EBM program.

In this week’s paper, the authors reviewed five different approaches to establish reference levels to evaluate EBM programs: i) use of existing reference levels (applied to EBM without any modification), ii) reference directions (applied to EBM after a consensus when there are poor data), iii) reference levels based on nonlinear functional relationships (which identifies environmental conditions or management actions that lead either to slight or dramatic changes in the ecosystem), iv) reference levels based on baselines (taking information from three types of ¨pristine¨ ecosystems: prior to human activity, inside protected areas or from remote locations with minimal human pressure), and v) reference levels based on social norms (incorporating social values). Furthermore, the authors make a short analysis of the application of these five approaches in order to evaluate the Puget Sound EBM program, which has become a national model of how EBMs must be implemented in the USA.

The discussion group started by recognizing that even though the 5 approaches proposed by the authors were appropriate scientific methods to evaluate an EBM program, it was not clear if the case study used was successful or not in illustrating how to apply these approaches. Therefore, the paper left us with a sense of lack of information.

The discussion then focused on three major points:

1. People should be more educated in science: management and political decisions should be based on scientific information. Ecology predicts what could happen to the ecosystem if certain actions were taken, so decision makers should take this in consideration in order to reduce biodiversity loss.
2. Science should consider people: there were different comments about the importance of including the social factor into the management, conservation and study of ecosystems. The idea of considering people’s expectations, and how these may change over time, in this social values approach was stated.
3. There is an urgent need for interdisciplinary panels in the decision making process: scientists should be involved in these. The major challenges are having the participation of ecologists and finding a way of helping people from a non- scientific background understand the ecological information.

Regardless of the ambiguity around what EBM involves, many countries have adopted it as their novel mode to manage natural resources and ecosystem services. Therefore, there is a need to answer the following questions:

• Is it appropriate to adopt EBM when its definition and monitoring are not clear enough?
• In the 1990s, Grumbine (1994) and Simberloff (1994) stated that EBM was been criticized by many scientists (i.e., biologists, ecologists, conservationists) because this type of management considers human’s benefit as a leading point for its utilitarian point of view (ecosystem would be managed according to humans needs). In a 2012 context, what are ecologist’s opinions?
• Crow (1994), stated that EBM urges for close relationships between scientists and ecosystem managers. Then, Carpenter (1996) made a call to the ecological science community to get involve in EBM programs. In a 2012 context, how can we encourage this collaboration? 

References:

• Carpenter, R.A. (1996). Ecology should apply to ecosystem management: A comment. Ecological Applications, 6(4), 1373-1377.
• Crow, T. (1994). Ecosystem Management. Bulletin of the Ecological Society of America, 75(1), 33-35. Retrieved from: http://www.jstor.org/stable/20167817. 
• Grumbine, R.E. (1994). What Is Ecosystem Management?. Conservation Biology, 8(1), 27-38). doi:10.1046/j.1523-1739.1994.08010027.x  
• Samhouri, J., Levin, P., James, A., Kershner, J. & Williams, G. (2011). Using existing scientific capacity to set targets for ecosystem-based management: A Puget Sound case of study. Marine Policy, 35, 508-518. doi:10.1016/j.marpol.2010.12.002
• Simberloff, D. (1998). Flagships, umbrellas, and keystones: is single-species management passi in the landscape era?. Biological Conservation, 83(3), 247-257. doi:10.1016/S0006-3207(97)00081-5

Plant-herbivore coevolution in a changing world

Human impacts on the environment, such as habitat destruction and fragmentation, climate change, invasive species, over-exploitation and pollution are causing a rapid loss of biodiversity. We only have limited knowledge on the impacts of biodiversity loss on ecological and evolutionary processes. Much of what we know of current diversity loss is on single species level and little is known about the impact on species interactions (Leimu et al. 2012).

Coevolution as proposed by Ehrlich and Raven (1964) in their classic paper was responsible for much of the fantastic diversity found in modern insects. Plants evolved chemical defenses to protect themselves from herbivore damage and consequently insects evolved adaptions to these chemicals. Coevolution is seen to be a dominant process that has shaped much of the biodiversity on the planet.

Human induced environmental changes such as habitat fragmentation reduce populations sizes. Climate change may reduce the size of optimal habitat available for populations therefore contributing to population reduction. Small populations can lead to inbreeding and reduced genetic variation. These factors are likely to influence plant-herbivore coevoluntionary processes by affecting a species ability to respond to selection pressure (Leimu et al 2012).

The ability of some plants to become weeds in a non-native habitat has been attributed to their release from their coevolved natural enemy allowing reallocation of resources from chemical defense into growth and reproduction (Zangerl and Berenbaum, 2005). The introduction of biocontrol agent, generally a species that has coevolved with the invasive species may control the pest. Zangerl and Berenbaum (2005) give an example how a plant weed become more toxic after its natural enemy was released as a biocontrol agent. In the absence of its natural enemy the toxicity of the plant reduced but when the coevolutionary relationship was re-introduced the plant again began producing toxic chemicals. As shown by this example there is a need to consider the coevolutionary history of interacting species when proposing biocontrol of an invasive species.

The group discussion queried how would it be possible to determine if plant-herbivore coevolution had been conserved or even if it is possible to conserve such relationships.

The paper discussed concludes with Leimu et al. (2012) determining that urgent study is needed to investigate the interactive effects of the major drivers of biodiversity loss. A criticism of this continuing wish for more study was brought up by a member of the discussion group. How much investigation is needed before conservation action is taken? Martin et al. (2012) document the demise of a small insectivorous bat endemic to Christmas Island. The decline of the bat was documented from 1986 and the species has been monitored intensively since 2004. Sadly the bat is now extinction because of a lack of action even though it was very obvious that this species was in trouble with only 20 individuals left.

Is it possible to conserve plant-herbivore coevolution? Does it really matter whether or not ALL coevolving relationships are conserved? New Zealand plant species evolved without browsing mammals, can they or are they already coevolving with these new herbivores?

References

Ehrlich, P. R., & Raven, P. H. (1964). Butterflies and Plants: A Study in Coevolution? Evolution, 18, 586-608.

Leimu, R., Muola, A., Laukkanen, L., Kalske, A., Prill, N., & Mutikainen, P. (2012). Plant-herbivore coevolution in a changing world. Entomologia Experimentalis et Applicata, 144, 3-13.

Martin, T. G., Nally, S., Burbidge, A. A., Arnall, S., Garnett, S. T., Hayward, M. W., et al. (2012).

Acting fast helps avoid extinction. Conservation Letters, 0, 1-7.

Zangerl, A. R., & Berenbaum, M. R. (2005). Increase in toxicity of an invasive weed after reassociation with its coevolved hervivore. Proceedings of the National Academy of Sciences of the United States of America, 102(43), 15529-15532.

Global food security, biodiversity conservation and the future of agricultural intensification

The rapid increasing human population challenges our food supply in terms of achieving efficient and productive agricultural land use, while also conserving biodiversity. The debate whether land for nature and for production should be segregated (sparing) or integrated (sharing) with wildlife is ongoing. Inappropriate agricultural management can lead to environmental degradation and conventional agriculture intensification often results in contamination by pesticides and fertilizers, which can affect human health and create non-target effects on wildlife and functional agro biodiversity (Meehan et al., 2011).

Tscharntke et al. (2012) argues that implementing agro-ecological principals in agriculture, i.e. adopting eco-efficient and environmentally friendly management with a focus on more diversified cropping systems can greatly improve productivity and contribute to closing yield gaps. Further, Tscharntke et al. (2012) states that linking agricultural intensification with biodiversity conservation requires well-informed, regional solutions and the challenge is more complex that first assumed.

The paradox of scale is the phenomenon whereby small and diversified farmers, rather than large monocultures, show greater productivity per area (Horlings and Marsden, 2011). Community-managed forests suffer from lower deforestation rates than protected forests (Porter-Bolland et al., 2012), which highlights the importance of participation and involvement of rural communities.

We discussed the complexities of linking global food security, biodiversity and agricultural intensification. Food security is needed where the hungry live, which is often within a landscape matrix of ecosystems that are rich in biodiversity. Thus, the intensification of agriculture will necessarily be different from one place to another and from one country to another all depending on conditions, agricultural culture and history. This led to thoughts about interpretations of terms as environment, sustainability and organic farming.

To ecologists the issue is about land sparing versus land sharing, but for the average consumer it may be simpler; the choice of conventional versus organic products. Consumers are a part of the driving market power that determines whether the food is produced conventionally or organic. Pure and Green’s promotion for organic products gives a simplified suggestion of what organic means. Check out link for YouTube video (4:29 minutes). http://www.youtube.com/watch?v=BebNsezt6r0&feature=related

Is it that simple? Should we as scientists involve the general population more in the details on the consequences of agriculture? Is it important and possible to engage consumers in biodiversity and the effect of agricultural management?

References

Meehan, T.D., Werling, B.P., Landis, D.A., Gratton, C., 2011. Agricultural landscape simplification and insecticide use in the Midwestern United States. Proc. Natl. Acad. Sci. USA. doi:10.1073/pnas.1100751108.

Horlings, L.G., Marsden, T.K., 2011. Towards the real green revolution? Exploring the conceptual dimensions of a new ecological modernization of agriculture that could ‘feed the world’. Global Environ. Change.

Porter-Bolland, L., Ellis, E.A., Guaruiguata, M.R., Ruiz-Mallen, I., Negrete- Yankelevich, S., Reyes-Garcia, V., 2012. Community managed forests and forest protected areas: an assessment of their conservation effectiveness across the tropics. Forest Ecol. Manage. 268, 6–17.

 Tscharntke, T., Clough, Y., Wanger, T.C., Jackson, L., Motzke, I., Perfecto, I. Vandermeer, J., Whitbread, A. Global food security, biodiversity conservation and the future of agricultural intensification, Biological Conservation 151 (2012) 53–59.