Review: Izsak, Price (2001) Measuring β-diversity using a taxonomic similarity index, and its relation to spatial scale. Marine Ecology Progress Series, 215:69-77.

Feature Paper: DOWNLOAD * Izsak, Price (2001) Measuring β-diversity using a taxonomic similarity index, and its relation to spatial scale. Marine Ecology Progress Series, 215:69-77.

Author Abstract: We present a new similarity index, taxonomic similarity (ΔS), which can be used to measure β-diversity. ΔS utilises species presence/absence data, and incorporates both higher taxon richness and evenness concepts. It is derived from the average taxonomic distance (relatedness) of any 2 species from different sites. Therefore ΔS is analogous to taxonomic distinctness recently developed for biodiversity assessment at α- and γ- (landscape or seascape) scales. ΔS is a new index, although its derivation uses a concept similar to the ‘optimal taxonomic mapping statistic’ developed independently for quantifying structural redundancy in marine macrobenthos. Using echinoderm data, we show that ΔS exhibits smoother behaviour and is less influenced by species richness, and hence sampling effort, than the widely used Jaccard coefficient of species similarity. We also believe ΔS to be a more intuitive and comprehensive measure of similarity than Jaccard and other conventional indices based solely on species held in common. Taxonomic similarity between sites is computed for echinoderms examined over 3 different spatial scales: local/small-scale (<10 km), intermediate-scale (10 to 100s km) and province/oceanic-scale (100s to 1000s km). Taxonomic similarity between sites increases progressively with spatial scale, with significantly lower values and higher β-diversity at small spatial scales. The same pattern is evident for species similarity, using the Jaccard coefficient. Possible explanations for this pattern centre on: (1) the large-scale oceanic area examined (Indo-West Pacific), representing a metapopulation of echinoderms for the 2 other, smaller areas examined within (Pula Wé, Sumatra and Lakshadweeps); (2) greater biophysical instability and unpredictability at small spatial scales. Compared with larger spatial scales, these may be characterised by greater likelihood and influence of species migrations and extinctions on a site’s total species composition. Hence, species composition may be highly changeable at small scales, leading to high β-diversity. These findings are based on 1 set of comparative data for 1 faunal group. Any wider conclusions drawn would be premature, although corals may also show greater β-diversity at small spatial scales. The extent to which patterns observed are evident for other marine species groups is not well known.

Note to Readers: Follow links above for author email, full article text, or the publishing scientific journal. Author notes in my review are in quotes.

Review: Today we will look at a then-new similarity index, called "taxonomic similarity) and how it relates to β-diversity, or beta diversity. According to Wikipedia, β-diversity can be defined as "the rate of change in species composition across habitats or among communities. It gives a quantitative measure of diversity of communities that experience changing environments." Therefore, unlike alpha diversity (or pure species counts for an individual location), β-diversity compares the species diversity between locations and looks at change across locales, while gamma diversity looks at β-diversity across a very large regional or global scale. Like Monday's paper (first paper this week) I encourage readers to download the full article to learn the mathematical formulas for the taxonomic similarity index defined. What I'll do is just look at the basics of the paper and interested readers can follow up with the download link to learn more.

The authors use species presence / absence data (checklists) to derive "the average minimum path length between any 2 species in different sites / areas." They use "path lengths" based on taxonomic relatedness, in the following way: "taxonomic path lengths are 0 (same species), 1 (different species but same genus), 2 (different genus but same family), 3 (different family but same order), etc. However, path length here refers to species in different sites / areas, rather than in only one site / area."

A summary of how the authors look at taxonomic similarity can be seen in their figure, below:

In their paper, the authors also showed the effect of increasing sampling effort and sampling area on taxonomic similarity measurements, but I'll leave it to interested readers to follow up, since the authors go into a very extensive analysis and compare their results and index to the Jaccard similarity index.

The authors further point out that while alpha diversity is quite well known in the marine environment (presence / absence checklists are one of the staples of marine biodiversity studies), beta diversity is less well known and that they hope their similarity index (which "appears to be less influenced by sampling effort than [the] Jaccard [index]") helps contribute to scientific progress. Furthermore, their index also seems to be less influenced by difference in area between localities, though common sense would dictate that one should try to compare relatively similarly sized areas… but sometimes only country-level data are available and at least there is some way to compare such areas.

The authors conclude by mentioning that all taxonomic levels ("not just species") should be considered in biodiversity studies, though many authors have shown that at least for the majority of tropical marine organisms, biodiversity is relatively similar across taxonomic levels (though not for all organisms so one must be careful about drawing comparisons between their group of interest and other groups).

Review: Clarke, Warwick (2001) A further biodiversity index applicable to species lists: variation in taxonomic distinctness. Marine Ecology Progress Series, 216:265-278.

Feature Paper: DOWNLOAD * Clarke, Warwick (2001) A further biodiversity index applicable to species lists: variation in taxonomic distinctness. Marine Ecology Progress Series, 216:265-278.

Author Abstract: A further biodiversity index is proposed, based on taxonomic (or phylogenetic) relatedness of species, namely the ‘variation in taxonomic distinctness’ (VarTD, Λ+) between every pair of species recorded in a study. It complements the previously defined ‘average taxonomic distinctness’ (AvTD, Δ+), which is the mean path length through the taxonomic tree connecting every pair of species in the list. VarTD is simply the variance of these pairwise path lengths and reflects the unevenness of the taxonomic tree. For example, a species list in which there are several different orders represented only by a single species, but also some genera which are very species-rich, would give a high Λ+ by comparison with a list (of equivalent Δ+) in which all species tended to be from different families but the same order. VarTD is shown to have the same desirable sampling properties as AvTD, primarily a lack of dependence of its mean value on the sample size (except for unrealistically small samples). Such unbiasedness is of crucial importance in making valid biodiversity comparisons between studies at different locations or times, with differing or uncontrolled degrees of sampling effort. This feature is emphatically not shared by indices related to species richness and also not by properties of the phylogeny adapted from proposals in other, conservation contexts, such as ‘average phylogenetic diversity’ (AvPD, Φ+). As with AvTD, the VarTD statistic for any local study can be tested for ‘departure from expectation’, based on a master taxonomy for that region, by constructing a simulation distribution from random subsets of the master list. The idea can be extended to summarising the joint distribution of AvTD and VarTD, so that values from real data sets are compared with a fitted simulation ‘envelope’ in a 2 d (Δ+, Λ+) plot. The methodology is applied to 14 species lists of free-living marine nematodes, and related to a master list for UK waters. The combination of AvTD and VarTD picks out, in different ways, some degraded locations (low Δ+, low to normal Λ+) and the pristine island fauna of the Scillies (normal Δ+, high Λ+). The 2 indices are also demonstrated to be measuring effectively independent features of the taxonomic tree, at least for this faunal group (although it is shown theoretically that this will not always be the case). The combination of Δ+ and Λ+ is therefore seen to provide a statistically robust summary of taxonomic (or phylogenetic) relatedness patterns within an assemblage, which has the potential to be applied to a wide range of historical data in the form of simple species lists.

Note to Readers: Follow links above for author email, full article text, or the publishing scientific journal. Author notes in my review are in quotes.

Review: Today is the first of three papers on how measurements of taxonomic similarity between populations are used to determine biogeographic affinities between locations. This paper is a bit complicated in that they introduce specific mathematical formulas for assessing taxonomic similarity. I won't go into the mathematics in my review because I aim to help both laypersons and new graduate students (or advanced undergraduates) understand the reviews. The basics of the mathematical principles are described in the author's abstract above in any event. I encourage those wishing to know more about the subject to follow the download link for a free copy of the complete article.

I also want to point out that prospective or current Master's of Science students should examine this article and others in the journal Marine Ecological Progress Series (MEPS) as one professor once told me that a Master's degree thesis is basically a MEPS-worthy paper. Use MEPS as yore guideline when trying to decide scope of a research project or when determining how much of an advisor's idea you can tackle in about one year of research and one year writing up the results for your thesis. Don't do more… trust me. Save that for your PhD and Postdoc.

Now, onto the review. As the first paragraph of the authors' article states: 

"Species richness measures have traditionally been the mainstay in assessing the effects of environmental degradation on the biodiversity of natural assemblages of organisms. However, the sampling problems associated with ascertaining true species richness and making comparable assessments with historical data are well-known, and it should be noted that richness is not the only measurable component of community level biodiversity, even when the data consist simply of lists of species presence/absences. The phylogenetic structure of the assemblage is also clearly important, and an assemblage comprising a group of closely related species must be regarded as less ‘biodiverse’ than an assemblage of the same number of more distantly related species, for example all belonging to different phyla. Measures of phylogenetic structure, based on analysis of cladograms of particular groups of organisms, have been proposed by conservation biologists as a means of assigning conservation priorities that preserve the greatest amount of phylogenetic diversity or ‘evolutionary history’ (May 1990, Vane-Wright et al. 1991, Williams et al. 1991, Faith 1992, 1994, Humphries et al. 1995, Nee & May 1997). Little attention, however, has been devoted to analysis of the ways in which environmental degradation affects phylogenetic structure on local or regional scales, and the extent to which properties of this structure can be used as measures of biodiversity for the purposes of biological effects monitoring."

I copied the entire paragraph because not only is it an excellent example of scientific writing, but it clearly states the problem the authors seek to address in their paper. To address the problem at hand (last sentence in the author introduction above), the authors use the concept of "taxonomic distinctness," which they define as "a measure of the average degree to which individuals in an assemblage are related to each other."

Oftentimes when researchers want to conduct global or large-scale analyses of target species, the highest resolution consistent data available are species presence-or-absence lists, also known as checklists. Usually, scientists use such lists to determine taxonomic diversity and total richness, but the authors propose determining "average taxonomic distinctness" of populations, for which they provide formulas (look to the original article).

But in essence, what the authors are trying to point out is that when confronted with only checklists, one needn't be restricted just to total species (or other taxonomic levels) richness. One can determine which locations are related to each other based on species compositions that are shared. Recall last Saturday's review (Week 5 Paper 2) where atolls have characteristic floras and faunas and how rainfall and island elevation can help structure and determine how related those floras and faunas are. 

The authors' taxonomic distinctness levels can be used to aid historical biogeography through determining sources of radiation or speciation events. The authors also use their metric to show how environmental degradation can skew species richness and thus can help determine which species are likely to "drop off" or go locally extinct. Thus, taxonomic distinctness can be used for management purposes, as well as for computer simulations to test various historical biogeography theories.

The authors also state that "Theories of island biogeography have largely been developed from data on species that are easily censused and for which complete inventories can be produced in relation to island size, such as birds, reptiles and certain groups of insects (MacArthur & Wilson 1967). For groups such as free-living nematodes, or other small cryptic taxa, a complete census is rarely possible, except for very small areas. [Taxonomic distinctness measures] therefore offer a useful alternative, and might also help to address longstanding questions concerning island biogeography that cannot be resolved by a count of the number of species alone: for example whether increasing numbers of species are a function of increasing island size per se, or are related to the larger number of habitats."

The authors then conclude with: "Because of the impracticality of routinely attempting comprehensive surveys, surrogacy methods will clearly become the norm in biodiversity estimation (Harper & Hawksworth 1994), and the search for appropriate indicators of marine and coastal biodiversity has become an important research goal (Feral 1999)."

In essence, this is what nearly all fieldwork is: gathering a sample subset of an entire population and hoping that you can sample enough to draw statistically powerful conclusions about the whole population. Furthermore, if certain "keystone" or important species are known to have a tight relationship with other organisms of interest, studying the one will often provide information about the state of the other. 

For example, butterflyfishes are mostly coralivorous, with many being obligate coralivores. This means that many butterflyfish species only eat living coral. Therefore, counting butterflyfishes on a reef and knowing a given reef area can help coral reef biologists determine approximate levels of coral cover needed to sustain such levels of butterflyfishes.

Next we'll look at how beta-diversity can be measured from another kind of taxonomic similarity index. Download links below as usual.

Review: Stoddart (1992) Biogeography of the tropical Pacific. Pacific Science, 46(2):276-293.

Feature Paper: DOWNLOAD * Stoddart (1992) Biogeography of the tropical Pacific. Pacific Science, 46(2):276-293.  

 

Author Abstract: Many previous biogeographic regionalizations of the islands and reefs of the tropical Pacific are unsatisfactory: the regions as defined are heterogeneous, localities with unlike biotas are grouped together, and those with similar characteristics are placed in separate categories. Often distinctions appear to be based on cultural or political rather than biogeographic considerations. Criteria are defined for the establishment of biogeographic boundaries. lnstead of the hierarchical schemes often utilized, it is proposed that the basis of biogeographic regionalization be typological. A distinction is made between the biogeographic characteristics of atolIs and other reef islands, elevated limestone (makatea) islands, and high (often volcanic) islands. It is concluded that if the first two categories are filtered out, the treatment of the biogeography of the third group and hence the regionalization of the Pacific becomes relatively unproblematical.

Note to Readers: Follow links above for author email, full article text, or the publishing scientific journal. Author notes in my review are in quotes.

Review: Today we'll complete our look at some applications of biogeography aimed at applying global biodiversity analyses towards conservation and management of those resources. 

As mentioned last week, the official download link for the Stoddart article is a TXT file and misses the figures that I believe are an integral part of the article, which aims to provide a visualization of different "schemes" meant to classify the Pacific Ocean islands that tend to be overlooked with many biogeography schemes. In fact, most maps of the world divide the globe through the Pacific, while it would make more sense geographically to divide it through the Atlantic Ocean.

Because of these reasons, I've decided to post every figure from the article in my review, which I hope is acceptable to the publishers for two reasons: 

The publisher (University of Hawaii) has provided a freely-accessible TXT file (lacking figures) of this article on the official download link at the beginning of this review; and 

The article is from 1992 and doesn't provide any "breaking-edge" research, at least now (being nearly 20 years old). 

Okay, on to the review. To illustrate how important the figures are, I won't even discuss the majority of points detailed in the text but rather, I'll provided commentary and summaries about each figure in turn, which should suffice to provide an excellent review of the entire article in any case.

Figure 1. "Biogeographic regionalization of the Pacific (after Gressitt 1956, 1961)." As Stoddart points out, "Gressitt's [biogeographical] scheme involves a hierarchy of regions, subregions, divisions, and subdivisions, though how these are related is not immediately apparent from his map." The major biogeographical divisions that Gressitt uses (islands that he felt were best related to each other in terms of distributions of plants and animals on land and in the water) totaled 12, with major divisions for the main Japanese Islands, the Ryukyus, the South China Sea, Papua New Guinea, eastern Australia, New Zealand, and 6 subregions encompassing the Pacific Islands. He grouped Micronesia together from Palau to Johnston Atoll, and grouped Eastern Polynesia together (the Line Islands, some of the Cook Islands, all of French Polynesia, and Pitcairn and Easter Island), with smaller unique regions set aside for 1) The Hawaiian Islands; 2) Southern Polynesia from the Phoenix Islands south through Samoa to the western Cook Islands; 3) Melanesia east of the Solomon Islands; and 4) New Caledonia. However, as Stoddart mentions, Gressitt placed too much emphasis on human culture and communities in demarcating his divisions (e.g., Polynesian VS Micronesian) rather than just plants, but in Stoddart's view, this stance isn't unique to Gressitt. Rather, "there is a persistent and indeed illogical tradition in Pacific insular biogeography that places weight on the comparatively recent human settlement of the area and the cultural differences between island groups that have resulted." However, sometimes one must be careful when looking at plant and animal checklists for the Pacific, as those cultural aspects (i.e., the habitation of humans) have often resulted in certain animals (and sometimes plants) going extinct through human activities. Thus, one must know (which is impossible with 100% certainty), what the "proto-Pacific" floras and faunas were (i.e., the plant and animal compositions before humans arrived).

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Figure 2. "Biogeographic regionalization of the Pacific (after Thorne 1963)." Comparing this scheme to Figure 1 above, one can see that a lot of the southwest Pacific biogeography remains the same (with a few shifts of boundaries) but that the central Pacific is more generalized. Otherwise, it follow the same methodology and downfalls of Figure 1.

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Figure 3. "Biogeographic regionalization of the Pacific based on the distribution of the Cypraeidae (Mollusca) (after Shilder 1961)." In this Figure, Shilder only looked at one group of mollusks, the cowries. Based purely on the distributions of various taxa of cowries, Shilder created the following biogeographic divisions of the Pacific, with all islands within a given division relatively related to each other in terms of cowry species than islands in another division.

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Figure 4. "Biogeographic regionalization of the Pacific based on Udvardy (1975)." The main criticism Stoddart brings up is how heterogenous Udvardy's scheme was, especially in division VI where the equatorial Phoenix islands are grouped with the subtropical Kermadec Islands. Likewise, New Caledonia is grouped with Norfolk Island and Lord Howe, quite dissimilar areas.

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Figure 5. "Biogeographic provinces of the area covered by the South Pacific Commission (after Dahl 1979, 1980)." Dahl's scheme seems to be based significantly on political units (because the regionalization was limited to a political division in the first place, the South Pacific Commission. However, Stoddart notes that a few islands that transcend political boundaries are grouped together reasonably (e.g., Lord Howe, Norfolk, and the Kermadec islands).

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Figure 6. "Distribution of atolls and reef islands in the tropical Pacific. Numbers refer to mean annual rainfall distribution in meters (dashed lines). Black circles are treeless dry islands." This scheme avoids all biological components and purely looks at physical characteristics of island elevation. The boundaries of atolls and low reef islands are circled and rainfall data are plotted within the region noted.

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Figure 7. "Mean annual rainfall and Fosberg zones in the west-central Pacific (Marshalls, Kiribati, and Tuvalu). Rainfall data from Taylor (1973)." This figure details how various islands from 20ºN to 20ºS fall on a range of rainfall data, with the resulting curve being divided into zones named after Fosberg, meant to delineate the similarity of islands based on rainfall coupled with latitude. As Stoddart notes, "the main controls on atoll biota in the Pacific are ecological. Atoll vegetation responds asymmetrically to rainfall extremes: it is more sensitive to drought than to wetness." Starting in Fosberg zone 1, there is insufficient rainfall to support coconuts. In zone 2, Pisonia forests begin. "In zone 3 there is Cordia, Pemphis, mixed forest, and coconuts. In zone 4 ther is Neisosperma forest and breadfruit; in zone 5 coconuts and breadfruit; and in zone 6 dense forest. Zones 7, 8, and 9 mirror zones 5, 4, and 3 to the south."

I'm skipping Figure 8, which deals with numbers of plans in the Marshall Islands based on rainfall because I think Figures 6 and 7 make it clear that rainfall is important in determining animal and plant compositions on islands. Stoddart does note that "atoll floras are unresponsive to land area (and indeed distance from presumed source area) but instead reflect rainfall [with very few exceptions]."

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Figure 9. "Raised makatea islands in the tropical Pacific. These islands are abundant west of the solid line (i.e., in the Solomon, New Guinea, Palau, Marianas, Fiji, and Tonga); black circles show makatea islands or volcanic islands with substantial raised limestone in the open Pacific." Again, this scheme merely maps out the geography of the Pacific irregardless of biota, with high limestone islands  (called makatea in various Polynesian tongues) and high volcanic islands and atolls noted.

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Figure 10. "High islands in the tropical Pacific. These islands are frequent west of the continuous line; possible biogeographic boundaries within this area are indicated. East of the line individual islands or clusters of high islands are indicated. Numbers refer to mean annual sea-level rainfall in meters, though this may vary widely according to topographic situation (rainfall data from Brookfield and Hart 1966 and Taylor 1973)." Stoddart, in recognizing how the Pacific is dotted with islands but having vast water barriers between, and how atolls are different from high islands, has produced the map below to note only high islands (circled) with rainfall data provided, and some attempt at biogeographic scheming from Samoa west to New Guinea and north to Japan.

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Figure 11. "Distribution of native land bird species in the tropical Pacific (excluding the easternmost Pacific). Data from Pratt et al. (1987) and other sources." The numbers below merely show land bird (non-flying and non-migratory birds) taxonomic abundance throughout the Pacific islands, showing that New Guinea has the most species (325) followed by some other Melanesian islands (Fiji, Santa Cruz Islands) and then other scattered pockets of medium diversity elsewhere (Hawaii, Galapagos, Tonga, Samoa, Palau).

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Figure 12. "Pacific limits of the seagrass genera Thalassea (TH), Enhalus (EN), Halophila (HA), and Syringodium (SY). Data from Den Hartog (1970), with additions." The figure is self-explanatory, as is the next one.

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Figure 13. "Pacific limits of the mangrove genera Rhizophora (RH), Avicennia (AV), and Excoecaria (EX). Data from various sources."

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Figure 14. "Generic diversity of scleractinian corals in the tropical Pacific (after Coudray and Montaggioni 1983)." Since Stoddardt's day, Veron's (2000, with additions) Corals of the World treatise has refined Coudray and Montaggioni's figure below, especially in the Indo-West Pacific (barely shown below). Still, what is key to note is how diversity scales or drops off from west to east, with highest diversity around Papua New Guinea and least in the Eastern Pacific.

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Figure 15. "Distribution of numbers of taxa in the genus Strombus (Mollusca, Gastropoda); the solid line shows the eastern limits of Strombus labiatus (after Abbott 1960)." Like the cowries, the figure below notes another mollusk, the conchs, though they are less abundant than cowries both in terms of species numbers (overall diversity) and distribution.

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Figure 16. "Distribution of families of warm-water marine shorefishes in the tropical Pacific (after Springer 1982)." Of particular note is how the shorefishes (or reef fish) diversity is similar in pattern to Figure 14, coral generic diversity.

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Figure 17. "Distribution of species of damselfish (Pomacentridae) in the tropical Pacific; the solid line shows the eastern limits of Amphiprion clarkii (after Allen 1975 in Briggs 1984 and Springer 1982)." This figure refines Figure 16 above by looking only at damselfishes, one of the most diverse reef fish families, with the most widespread clownfish species marked off with the solid line. Note how the Great Barrier Reef and Papua New Guinea have the highest diversities.

To conclude, one must take Stoddart's paper with an understanding of the state of knowledge in 1992 when it was written. Nowadays, biogeographers use powerful databases to quickly generate hundreds of maps tailored to individual species or taxonomic groups in their ever-refined quest of determining global biogeography patterns. Stoddart's attempt to consolidate all relatively recent views of Pacific Island biogeography while lacking a lot of the computer tools of biogeographers today should be applauded and there are still gems to be found in his paper nearly 20 years later.

For while the modern biogeographic figures have been refined here and there for individual groups since Stoddart's day, the same basic principles Stoddart pointed out remain true: many tropical organisms have similar diversity patterns in the Pacific, but that atolls should be separated from high islands in data sets for terrestrial faunas and floras. Also, diversity tends to be greater in the tropics compared to temperate waters.

While I've skimmed over the figures above I hope that everyone spends just as much time as you did reading this review as for reviewing the figures and making your own conclusions based on the numbers and patterns shown.

I hope everyone's enjoyed this review. Next we'll look at taxonomic similarity indices, which have grown out of the need to analyze ever-vaster species checklists globally and determine how the floras and faunas of such regions are related. In other words, we'll see what biogeographers are doing now to address Stoddart's question.

Review: Sherman, Duda (1999) An ecosystem approach to global assessment and management of coastal waters. Marine Ecology Progress Series, 190:271-287.

Feature Paper: DOWNLOAD * Sherman, Duda (1999) An ecosystem approach to global assessment and management of coastal waters. Marine Ecology Progress Series, 190:271-287.

Author Abstract: Since the Rio Summit in 1992 the public has become increasingly aware that coastal ecosystems are under signficant threat from pollution, overexploitation, and habitat loss. However, little progress has been made in sustained global actions to reverse their degraded state. It has been no small feat for the world community to come to agreement on international instruments identifying environmental and resource problems, but it is another matter altogether to muster the scientific community and the political will to enact necessary policy reforms and devote necessary funding to restore and protect valuable marine ecosystems. An ecosystems approach is emerging for the assessment and management of coastal waters around the globe utilizing modular strategies for linking science-based assessments of the changing states of large marine ecosystems to socioeconomic benefits expected from achieving long-term sustainability of their resources. To assist developing countries in implementing the ecosystems approach to marine resources development and sustainability in international waters, the Global Environment Facility and its $2 billion trust fund has been opened to universal participation that builds on partnerships with the United Nations Development Programme, the United Nations Environmental Programme, and the World Bank.

Note to Readers: Follow links above for author email, full article text, or the publishing scientific journal. Author notes in my review are in quotes.

Review: This week we'll look at some applications of biogeography aimed at applying global biodiversity analyses  towards conservation and management of those resources.

This week's paper was borne out of the 1992 Rio de Janeiro International Summit on Biological Diversity (variously called the Rio Convention, Rio Summit, or 1992 Biodiversity Convention) and a need to develop management strategies on a global level for cooperating countries bound by the Rio Summit. The three main goals of the Summit were:

    1)    "Conservation of biological diversity / biodiversity"
    2)    "Sustainable use of [biological] components [in ecosystems]"
    3)    "Fair and equitable sharing of benefits arising from genetic resources"

This paper was written to note that while many governments worldwide agreed in 1992 to protect biological diversity around the world, that by 1999 little had been done to find the "political will to enact necessary policy reforms and devote necessary funding to restore and protect valuable marine ecosystems."

The authors focus mainly on coastal marine ecosystems, which are being degraded more every year. The authors proposed a method to "link [modular] science-based assessments of the changing states of large marine ecosystems to socioeconomic benefits expected from achieving long-term sustainability of their resources."

The method specifically notes "paradigm shifts" are needed in the following ways: changing the focus from "individual species to ecosystems, small spatial scales to multiple scales, short-term perspectives to long-term perspectives, [the idea of] humans independent of ecosystems to [an understanding that] humans are integral parts of ecosystems, management divorced from research to adaptive management, and managing commodities to sustaining production potential for goods and services."

The authors noted that before the Rio Summit there was the "Global Environment Facility" program to note 4 focus challenges for environmental managers globally:

    1)    Climate change
    2)    Biodiversity conservation
    3)    Ozone depletion
    4)    International waters

In switching to a more global approach, the authors created a map of 50 "large marine ecosystems" worldwide, shown below:

This paper is the first of many that have come since its publication with the aim at mesosystem analyses and determining boundaries of large marine ecosystems. If you note the figure above, though, many isolated island nations (particularly in the Pacific Ocean) are missing from such schemes, but this can be explained for this paper with the understanding that the authors were mainly concerned with coastal marine ecosystems and thus the authors focused mainly on continental coastlines. The authors' criteria for defining LME boundaries focus on "ecosystem (1) productivity, (2) fish and fisheries, (3) pollution and ecosystem health, (4) socioeconomic conditions, and (5) governance."

The paper also outlines a United Nations trust fund developed to aid poorer nations in gathering the resources necessary to apply the agreements of the Rio Summit (funded by 161 countries worldwide at rates depending upon GDP of donor nations, whereby richer nations help subsidize poorer nations). This fund was developed because for most organisms, as we've seen in the past weeks, biodiversity is higher in tropical waters compared to temperate waters. And since many tropical nations are poor (in Asia, Africa, and Latin America) compared to temperate nations (in Europe and North America), some system must be developed to help manage resources where their management hasn't been a priority. In the authors' words "subsistence fishing for protein and income must be sustained for the support of coastal societies that have few economic alternative."

Once the framework is developed (large marine ecosystems), the authors developed various metrics, or "experimental measures of changing ecosystem states and health," noted below:

    1)    Biodiversity
    2)    Stability
    3)    Yields
    4)    Productivity
    5)    Resilience

The authors note that samples aimed at determining ecosystem health should be "focused on parameters relating to the resources at risk from overexploitation, species protected by legislative authority (marine mammals), and other key biological and physical components at the lower end of the food chain (plankton, nutrients, hydrography), including zooplankton composition, zooplankton biomass, water column structure, PAR, transparency, chlorophyll a, NO2, NO3, primary production, pollution, marine mammal biomass, marine mammal composition, runoff, wind stress, seabird community structure, seabird counts, finish composition, finish biomass, domain acid, saxitoxin, and paralytic shellfish poisoning."

The authors also note that "special consideration should be given to improved knowledge of how the natural system generates economic values" and that the interconnectedness of ecosystems should be focused upon, such as how "coastal wetlands [act] as nurseries for fisheries, natural pollution filters, and storm buffers" rather than having managers of individual ecosystems not share knowledge across areas of interest. In other words, if you have a specialist in a certain field, they will be excited and interested and knowledgeable about all aspects in their field, but they may be ignorant of other ecosystems or fields that don't concern their area of focus. However, scientists and specialists in other fields may know, for instance, that their ecosystem of focus is related to another ecosystem in ways that other specialists may not.

The authors also point out that while focus should be made on protecting ecosystems rather than individual species, that "keystone species in a valuable ecosystem" should not be "sacrificed through ignorance" and lack of management. A keystone species, as defined by Paine (1995), is "a species that has a disproportionate effect on its environment relative to its biomass."

The authors summarize their view by noting that managers should "include a generalized characterization of the ways in which human activities affect the natural marine system and the expected 'sensitivity' of these forcing functions to various types and levels of human activity." The authors also note that "natural and social scientists should concentrate further on resolving apparent effects that are confounded by cycles or complex dynamics in the natural system itself."

At the core of such a collaboration, the authors note that at the minimum there should be:

    1)    Integrated waste management
    2)    Water pollution abatement
    3)    Habitat improvement
    4)    Conservation of stressed mangrove and coral reef areas
    5)    Coastal tourism development
    6)    Improvements of the municipal fisheries

In creating such a collaboration, the authors note that their must be "complementarity among international agreements" and that "detailed rules and standards at the global level exist to control pollution from ships, including at-sea disposal of sates, and for whales."
The authors state that from best practices experience, there are several lessons that have been learned to help address ecosystem-level problems:

1. "Donor-driven rather than country-driven institutional arrangements have proved ineffective and recipient countries must take ownership of activities"
2. "Water quality must be considered together with water quantity and ecological considerations in any sectoral development project if sustainable development is to be achieved"
3. "Ecosystem-based approaches, which encompass overfishing, habitat loss, and biological diversity issues in addition to water quality / pollution abatement, are needed for improving management of transboundary water systems"
4. "Interministerial and subnational government involvement is necessary in these joint, multi-country regional initiatives if actual changes in sectoral activities causing the transboundary problems are to be achieved."

The authors conclude their paper with a good summary figure aimed at describing the main problems facing coastal marine ecosystems across political boundaries, noted below:

And while this paper is more than 10 years old now, the recommendations and problems outlined by the paper are just as relevant today as when first published.

Next we'll look at a classic paper on pacific island biogeography. Because the online version that I have a link to (below) is missing figures, and the figures are such an integral part of the paper, I think it is fair for me to host the images from the paper, particularly since the paper text is provided by the publisher (University of Hawaii) freely.