Biodiversity estimates

Tropical forests are known to contain a disproportionately large share of the earth s biodiversity. Estimates of how many kinds of plants and animals inhabit the planet vary considerably, but it is generally agreed upon that, for certain groups, only a small fi action of the probable number of species have been discovered. It is anticipated that most of the species that are yet to be identified inhabit the tropics ( )-... 

An even more streamlined approach scores each stage of the life cycle for impact on a number of environmental indicators. Typical indicators include resource depletion, global warming potential, smog production, acidification, eutrophication, toxic waste production and biodiversity impact. Impact is estimated using a simple numerical scale. The completed matrix is used to focus attention on areas for improvement. 

P cycling, pre chain emissions, animal welfare, economics, biodiversity, product quality, soil quality, and landscape aesthetics [60]. Whole farm model (WFM) uses pasture growth and cow metabolism for predicting CH4 emissions in dairy farms. Also included in the WFM is climate and management information. However, recent reports also suggests that WFMs may incorrectly estimate CH4 emission levels as they do not take into account the DMI and diet composition while predicting the enteric CH4 emission. This low prediction efficiency of WFMs may lead to substantial error in GHG inventories [10,11],... 

For instance, Costanza et al. [24] estimated the value of 17 ecosystem services in 16 biomes to an average US 33 trillion (12 zeroes) globally. This value is almost twice the size of the compared global GDP (or Global Gross National Product to be precise). The ecological economists estimate these values so that ecosystems and biodiversity can be included in new calculations of economic efficiency and economic performance. 

Such losses are potentially serious problems for drug research. Maintaining biodiversity is an essential component of future research efforts to identify possible drugs in the world s plant and marine resources. Scientists have no idea how many species there are in the world, but reasonable estimates place the numbers at about 250,000 plant species and up to 1 million marine species. So far, no more than about 10 percent of all plants and 1 percent of all marine organisms have been studied for possible use as drugs. 

Taking higher taxonomic levels as an estimate of biodiversity (May 1994), more phyla are found in the oceans than on land. Also, with the only exception of the arthropods, phyla with representatives both on lai and in the sea are more speciose in the latter. 

If biodiversity decreases, natural product diversity also decreases, because of a link between the two (Part II). Modem times have seen the greatest natural product diversity. With the increase in plant species from 100,000 before the end-Cretaceous mass extinction to the 250,000 species of modem age, natural product diversity must also have increased. The estimate depends on how natural product diversity is evaluated, i.e. from the molecular skeletons or the actual metabolites. Metabolites of insects, fungi, and bacteria must be added to the list. The present man-made mass extinction may thus result in a larger numerical impact than any previous mass extinction, even if the loss of natiual product diversity occurs at the same percentage of previous catastrophes. 

Based on the rate at which novel microorganisms are being discovered, one can make an estimation of the amount of different organisms that have been identified up to now relative those that remain uncharacterized (Table 5.8). The overwhelming biochemical diversity present in nature makes that the isolation of microorganisms with novel enzymatic activities is worthwhile (reviewed in Bull, Goodfellow Howard Slater, 1992). Preferred sites to find novel enzymes include so-called mega-diversity countries such as Mexico, Colombia, Brazil or India and biodiversity hot spots like rain forest and deep seas. 

As parasites, flatworms have extended their global presence by taking advantage of the adaptations of many diverse invertebrate and vertebrate hosts. Many parasitic forms are host-specific and many of these are site-specific within or on their host. Contemplate on the biodiversity of vertebrates, consider that many platyhelminths use one or more intermediate hosts and one may just begin to grasp the diversity of parasitic flatworms. From the microscopic interstitial free-living species that live between particles of mud to the enormously long tapeworms of blue whales, an estimate of 100,000 extant species, of which only about 20,000 have been formally... 

From the estimates of Stoll-Kleemann and O Riordan (2004), about 70% of the land surface are anthropogenically affected causing changes in biodiversity thousands of times faster than would take place naturally. Global biodiversity cannot be maintained without changing the strategy of human behaviour in the sphere of environmental protection. Therefore, we should expect a crisis in biodiversity, unless international cooperation toward its protection becomes effective. 

A key step in any risk assessment is the collection of data to feed into the extrapolations. The use of an extrapolation method will be possible only with appropriate input data. The data that are needed can be literature data (e.g., laboratory toxicity data) or field data (measured or predicted environmental concentrations), and the extrapolation is then to move these toward common currencies, that is, the estimation of bioavailable concentrations, derived from total concentrations, in both test systems and the field, or species-to-community extrapolation when the concern is the effect of exposure on biodiversity. Step 6 will often be made together with Step 7, because a method without data is as useless as data without a method. 

It is estimated that only 1 % of the total microbial community has been cultured by standard isolation techniques. There is a growing conviction that this observation resulted from the selected media used, as well as incubation time and inoculum size. Additional stimulation factors for growth and sporulation (e.g. gamma-butyrolactones and indole-3-acetic acid) have been reported.41,42 This implies that the majority of microbial biodiversity still remains to be discovered and exploited. 

Fungi are the second largest group of eukaryotic organisms and rank second only to the insects in estimated species biodiversity. There are approximately 72,000 recognised species of fungi of an estimated 1-1.5 million in total. This means that <5% of fungal species have been described to date. 

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