What conservationists need to know about farming

 

Farming is the basis of our civilization. Though the world’s population is increasing largely and is expected to rise from the present 7 billion people to 9 billion by the year 2050 (UNPD, 2011) thus the demand for farm products increases accordingly. The United Nation’s Food and Agriculture Organization (FAO) estimates that the demand for food will rise 70 percent worldwide between year 2005 and 2050 (FAO, 2009). The great challenge for our civilization is that, although we are dependent on farming, at the same time farming is the most nature damaging sector of human activity to the planet. This is because farms are not closed systems but affect the surrounding environment. Biodiversity and wildlife are often the trade-off for farming. Tackling these issues requires conservationists to explore the many consequences that decisions about agriculture have beyond the farm. While it is important to consider conservation values on farmland, consideration also needs to be given to; what sorts of species are found where, the abundance of each species, agricultural yields, and the relative proportions of intact habitat and high- and low-yielding farming. There is a pressing need to measure how biodiversity varies with farm yield but also to consider other ecosystem services. We need to develop methods for how best to limit the cost of farming across a group of benefits important to society. Also it is important to identify likely “winners” based on data and not ideology when it comes to agricultural methods.  Land-sharing, land-sparing, push-pull, breeding and genetic modification techniques must be considered and evaluated. Further governmental regulation and land-use planning should likewise be considered, but with the market and consumer power in mind.

We discussed the advantages and disadvantages of land-sharing versus land-sparing. A member of the group shared experience of land-sharing not always being the best solution for enhancing ecological processes.  The group agreed that the most sustainable agricultural method in a given situation will be context and scale dependent. With the article’s example of nearly no research existing on chicken farming’s effect on the environment due to required cropland etc., a question on biodiversity was raised; could organic chicken farming be more harmful for the biodiversity than the conventional mass-production? Also discussed was the possibility of offering credit for farming biodiversity in order to motivate farmers to enhance biodiversity on their farms, since some farmers do care and listen to the public reactions of environmental impacts. It was suggested that increased diversity of farming within a landscape will increase biodiversity, though with that comment a discussion arose about agriculture responding to the market and that it is nearly impossible to put a price on biodiversity value. In addition, the issues of the general public only caring about conserving the cute animals and the pictures landscape was brought up with the question of; how can we make biodiversity valuable to the public?

Is the trade-off for biodiversity measurable? Is the bottom-line for a trade-off, between biodiversity and economic wealth? If so, where does that leave conservationists and the science of ecology?  

References

Balmford, Andrew et al., 2012, what conservationists need to know about farming, Proceedings of The Royal Society Journal, Biological Science.

FAO, 2009, Food and Agriculture Organization of the United Nations, State of food insecurity in the world 2009, Rome, Italy.

UNPD, 2011, United Nations Population Division, World population prospects: the 2010 revision. New York, United States.

 

Biodiversity and ecosystem services: Complementary approaches for ecosystem management?

Schneiders et al. (2012)

According to the Millenium Ecosystem Assessment (MA, 2003), ecosystem services (ES) are the benefits humans obtain from ecological systems. They can be classified as providing services, such as food; regulating services, like control of diseases; cultural services, as recreational; and supporting services, such as nutrient cycling. Many surveys are currently being conducted on ES, particularly addressing their economic valuation. These studies are contributing to the evaluation of strategies for alternative uses of land and, most importantly, may aid in demonstrating and justifying the urge for conserving biological diversity (Schneiders et al., 2012).

Furthermore, many researchers have stated that the quality and sustainability of ES could be directly influenced by, or strongly correlated with, the level of biodiversity of an ecosystem (MA, 2003, Cardinale et al., 2012, Schneiders et al., 2012). However, for many ES, the evidence for the effects that biodiversity has on them is mixed or insufficient. In addition, how biodiversity per se contributes to the ES is even less well defined (Cardinale et al., 2012).

This week’s paper aimed to resolve the much-discussed question ´Are biodiversity conservation, with the aim of preserving biodiversity, and ES, with the goal of sustaining human well-being, mutually beneficial or are trade-offs always inevitable?´. In order to address this aim, the authors:

• Analyzed the relations between biodiversity, ES and land use intensity for the region of Flanders through a comparison of their estimated values (generated by expert opinion) in grid maps (4km x 4 km). The researchers found a negative relationship between biodiversity and ES values and land use intensity values. 
• Described the relationships between biodiversity and land use intensity, for the long term future. Here, the authors discussed the importance of establishing a ´safe minimum standard of conservation´ (SMS) that is the ´lowest´ biodiversity level accepted by society. This SMS will help evaluating whether an ecosystem is healthy or not and if the use of ES are being sustainable.
• Applied ecosystem management in order to relate the current and the future target scheme. The researchers recommended different approaches of EM according to the characteristics of the areas: for zones with high levels of biodiversity, they recommended a biodiversity based approach; for zones with multifunctional uses and a good state as a future perspective, an ecosystem service approach was suggested; and for built-up zones and areas with intensive agricultural used, their advice was a technological service based approach. The authors suggested that by using this division of ecosystem management the joint achievement of biodiversity and ES goals would be easier. 

The discussion started with the statement that considering the main objective of ES is human well-being, conservation focusing on ES would focus mainly on species that make those kinds of services possible. Then, the group recognized the risk of this type of conservation for we only know few species and even less about their functions and the ES they are involved with. Therefore, it was stated that conservation efforts should focus on preserving as much as possible (the precautionary principle), except in those ecosystems where a specific ES is needed. 

Later, the discussion moved into ES being a buzzword. In the past, it helped to gather people from different disciplines together to talk about conserving biodiversity. Sadly, now ES is mainly being used as a tool for valuing how much money society can get from nature. The group recognized that the lack of environmental education and an emotional connection with nature would have predisposed societies to having an ‘I-only-care-about-having-money’ attitude. This lack of attachment to nature could be one of the causes that makes new generations insensitive to what happens around them and in their environment because they only care about getting the maximum profit from it. 

As for the paper itself, the group claimed that even though the findings obtained by the papers were not novel and they did not actually measure ES nor present any solution, the method of grid maps used was a good contribution for a spatial analysis and could be helpful in determining what type of management is appropriate according to the features of an area. The group also questioned the used of ´experts opinion´ in establishing the values for land use type (Appendix A of the paper).

Questions:

1. How can ecologists help current and future generations consider the importance of biodiversity and actually care about nature? A member of the group proposed including some ecology courses in the curricula. Will this be enough to change students´mentality?  
2. Considering that we cannot conserve all species, should conservation programs focus on species that provide ES? Will this actually help the conservation of the ecosystem and its functions? What about the other species?

 References:

1. Cardinale, B.J., Duffy, J.E., Gonzalez, A., Hooper, D.U., Perrings, C., Venail, P., Narwani, A., Mace, G.M., Tilman, D., Wardle, D.A., Kinzig, A.P., Daily, G.C., Loreau, M., Grace, J.B., Larigauderie, A., Srivastava, D.S., & Naeem, S. (2012). Biodiversity loss and its impact on humanity. Nature, 486(7401), 59–67. doi:10.1038/nature11148
2. MA. (2003). Millenium Ecosystem Assessment: Ecosystems and human well-being - a framework for assessment. Washington, U.S.A.: Island Press.
3. Schneiders, A., van Daele, T., van Landuyt, W., & van Reeth, W. (2012). Biodiversity and ecosystem services: complementary approaches for ecosystem management?. Ecological Indicators, 21(SI), 123-133. doi:10.1016/j.ecolind.2011.06.021

Why are metapopulations so rare?

Levins (1970) introduced the term 'metapopulation' to describe the concept of a population of populations. A metapopulation describes a set of subpopulations linked by rare dispersal events allowing for recolonizations after extinctions (Fronhofer et al. 2012). Interest in the metapopulation concept has increased substantially since the 1980s and since the mid-2000s c.400 articles relating to metapopulations have been published each year.

The metapopulation theory as defined by Levin (1969) has been frequently applied to conservation biology because two of its basic parameters are extinctions and recolonizations. The term has been used in a broad sense and despite the application to conservation biology very few empirical examples conform to the strict classical metapopulation model (CM) defined by Levins (Fronhofer et al. 2012).

Fronhofer et al. (2012) use the term spatially structured populations (SSP) to encompass metapopulations and other population structures such as mainland-island systems, source-sink and patchy populations. The group discussed the use of this terminology in ecology and how terms can be picked up by other disciplines and used in such a way that their meaning becomes vague or too broad. Hanski & Gilpin (1991) stated that ecology is afflicted with inconsistencies in the use of terms and concepts. Vague use of terms leads to grouping or splitting of ecological phenomena and can hinder attempts at understanding the real world.

Interestingly there was a lag phase in the uptake of the metapopulation theory. The theory of island biogeography dominated ecological thinking up to the late 1980s. The theory of island biogeography is related to the metapopulation concept in having the same fundamental processes: colonization and extinction (Hanski & Gilpin, 1991). The island biogeography theory looks at communities whereas the metapopulation theory relates to single species. One reason put forward for this lag by the discussion was that early work done on metapopulations were model driven. Empirical studies were difficult and time consuming to do. Social changes in the late 1980s brought environmental issues such as rainforest destruction to the fore. Metapopulation theory research was seen as a way of determining the consequences of habitat fragmentation. It also came to the forefront in the discussions on reserve design.

The importance of using the correct term was questioned: Does it matter if the term metapopulation or spatially structured population is used? The paper we discussed did address this question by suggesting assumptions may lead to resources being invested incorrectly leading to biodiversity loss. Management decisions for conservation have been based on the metapopulation theory but examples of the CM are rare in nature. The paper discussed states the CM concept is applicable to populations which are on the brink of extinction. These populations may already be too far down the track of extinction to save. The emphasis is on determining the type of SSP that is being conserved so the correct management decisions can be made (Fronhofer et al. 2012).

Does ecology need a system to create consistent definitions for ecological terminology?

Is the metapopulation concept relevant to applied areas such as conservation biology?

Is the individual-based modelling approach a useful tool for determining management strategies for conservation?

References

Fronhofer, E. A., Kubisch, A., Hilker, F. M., Hovestadt, T., & Poethke, H. J. (2012). Why are metapopulations so rare? Ecology, 93(8), 1967-1978.

Hanski, I., & Gilpin, M. (1991). Metapopulation dynamics: brief history and conceptual domain. Biological Journal of the Linnean Society, 42, 3-16.

Levins, R. (1969). Some demographic and genetic consequences of environmental heterogeneity for biological control. Bulletin of the Entomological Society of America, 15, 237-240.

Levins, R. (1970). Extinction. In M. Gerstenhaber (Ed.), Lectures on mathematics in the life sciences (Vol. 2). Providence, Rhode Island: American Mathematical Society.

Biodiversity for food and nutrition

Estimated 90 % of the world’s dietary energy supply is obtained from only 30 plant species, although more than 700 species through time have been cultivated for food (FAO, 1997). The forces behind this monocultural approach to agriculture are mainly economics, production volumes and market power of consumers. There is a great deal of variety in nutrient values even from the same species of fruit, grain or vegetable. The compositional difference among varieties or cultivars can be very significant for macronutrients, micronutrients and bioactive components. Different food species and a variety within species provides energy, nutrients thus contributes to food and nutrition security (Toledo & Burlingame, 2006). Data on the nutrient content of foods is very limited and this variation has been an ignored area of research, despite data on nutrient contents at the level of the genetic resource being important for the sectors of health, agriculture, trade and the environment. These sectors have different approaches for the use of such data, though some consensus can be reached towards a healthier population and healthier ecosystems. With agriculture of great variety in cultivars, the biodiversity in the ecosystems the agriculture exists in will accordingly be greater. According to the authors of the article; “food composition activities continue to improve the evidence base, which in turn gives value to ecosystems, the food species they contain, and the within-species diversity” (Burlingame et al. 2009).

We discussed the possibilities of using native species agriculture at larger scales; however, it is clear that the trade and economics are the determinant of agricultural cultivar use. Local communities might grow native species, such as potatoes in Peru, for their own use, but use high yield species for trade and export. In addition, we discussed the difference between the survival needs of local community farmers in comparison with the target of large scale agriculture to feed the world, and thus the pros and cons for the two sizes regarding profit and biodiversity. A member of the group even questioned the profit value of big scale agriculture versus loss of biodiversity.

From large scale agriculture to global money we also discussed the difference in ability to digest and absorb nutrients between world populations and continents. Nowadays people travel and move around the world, trends and advertisement follows thus the consumer behavior, demands and wanting follows too. The matching of physiological needs and abilities with the physical environment is being challenged in the attempt to make the world adapt to us. We further discussed the value of food and concluded it to be much more than only nutrition and physical needs, but also a social and cultural matter. With the example of children believing that eggs comes from Wal-Mart, the issues of respect and responsibility for agriculture and nature was raised.  

If our world is ruled by global money and trading, how can scientists make a difference in conserving nature, wildlife, biodiversity, etc.? How can different sciences cooperate in terms of reaching a common goal? And do we all have the same goal?

 

References:

Burlingame, B., 2009. Food composition is fundamental to the cross-cutting initiative on biodiversity for food and nutrition. Journal of Food Composition and Analysis, 22, 361-365.

FAO, 1997. State of world’s plant genetic resources for food and agriculture. FAO, Rome.

Toledo, A. & Burlingame, B., 2006. Biodiversity and nutrition: a common path toward global food security and sustainable development. Journal of Food Composition and Analysis 19, 477-483.