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2013. Available online at www.internationalscholarsjournals.org © International Scholars Journals 

 

 

Full Length Research Paper 
 

Economic of biodiversity: The importance of studies 
aimed at assessing the economic value of biological 

diversity 

 
Aynur Demir 

 
Aksaray University, Turkey. 

 
Accepted 15 September, 2013 

 
 

Biological diversity has constituted the focal point of environmental economics and public politics 
increasingly over recent years. Ecological and economic approaches guide the determination of 
accurate policies for a sustainable future and in drawing an efficient roadmap. Based on an extensive 
literature review, this study reveals both the importance and limitations of studies aimed at the 
economic value of biological diversity within the descriptive analysis and the method of group 
evaluation. In this study, it is shown directly that, studies which are based solely on biodiversity are 
seen to be insufficient. It is said that, the use values and non-use values of biodiversity to be 
determined as monetary and it is understood that, further policies can be developed on this subject. 
This study targeted an interpretation of the economic valuation concept by approaching key studies 
aimed at building bridges between a nation’s ecology and its economy. Revealing the value of the 
biological diversity both quantitatively and qualitatively, these studies reflect the difficulty in not only 
assessing the accurate evaluation regarding species and genetic differences, but also the ecological 
and economic substitution of possible biological diversity losses. 

 
Key words: Biological diversity, economic valuation, species diversity, ecosystem diversity, bio-prospecting 
value 

 
INTRODUCTION 
 
Biodiversity had been included into the economic policies 
and the sustainable development model as a rising value 
in terms of economy and ecology during the 21st century. 
Biodiversity plays an important role in the global economy 
and sustainable development due to two main reasons.  
“The first is that, it provides a wide range of direct or 
indirect benefits to mankind, which occur on both local 
and global scales. The second relates to how human 
activities have contributed to unprecedented rates of 
biodiversity loss, which threaten the stability and 
continuity of ecosystems as well as their provision of 
goods and services to mankind (Nunes and van den 
Bergh, 2001; Nunes and Nijkamp, 2011). 

 
 

 
Complex biodiversity indicates a healthy environment 
and a process of life-support required for the welfare of 
people through the various goods and services.  

Biodiversity, which is also an important part of 
economical development, is classified as scarce 
resources in the scope of economic goods, with a 
significant strategic power for both local and global 
economies (Pearce and Moran, 1994; Tisdell and Wilson, 
2006). The common and sustainable utilization of this 
power may be possible with the transformation to an 
economical value providing all the components of 
biodiversity (species, genetic, and ecosystem diversity). 
Therefore, attentions have shifted to the marketable 

 



Demir 5377 
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Figure 1. Methodological approach for valuation of biodiversity (Adopted from De Grood et al., 2002). 

 

 
goods and services directly provided from both local and 
global biodiversity together with the analysis and 
evaluation that highlights the negative economic value of 
biodiversity loss.  

The economic valuation studies which are based on an 
entirely human-centered approach take into account 
direct and indirect values of the production, consumption 
and unused values of biodiversity and they provide an 
opportunity to determine the monetary value on the basis 
of income to the mentioned values restricted (Costanza et 
al., 1997; Nunes et al., 2003; Saunders et al., 2006; De 
Groot et al., 2012). This economic valuation allows for a 
monetary evaluation of the value of biodiversity on the 
basis of revenue (Freeman, 2003; L’Opez, 2008). The 
determination of use and non-use values of biodiversity 
employs economical value techniques such as the market 
analysis, the production function, the hedonic pricing, 
travel cost and the conditional valuation (Figure 1) (De 
Groot et al., 2002; Hoffman, 2011).  

Research carried out on the determination of an 
economic value contribute to identifying the role of 
biodiversity on ecological and economic systems, 
providing a way to follow the negative impacts on 
species, ecosystems and related goods and service 
losses. Within an ecosystem the extinction of a species 
has a direct affect on many other species and breaks 
down the previously existing balance (Xepapadeas, 

 

 
2010). As a result of this, it has been observed that, 
certain key functions within the ecosystem are not fulfilled 
both inside and outside the system, together with the 
arrival of new species. It is highly unlikely the incoming 
species will continue to fulfil the exact functions 
performed by the now extinct species, leading to a 
breakdown within the ecosystem and possible habitat 
loss (Tisdell et al., 2006, 2007; Nunes et al., 2006). In 
this way, gradually decreasing biodiversity that has 
material, moral and functional values will disrupt the 
balance of nature and at the same time causing 
economical losses and the further extinction of some 
sectors. Furthermore, these economic valuation studies 
have a significant role in the conservation of biodiversity, 
through increased monitoring and the subsequent 
creation of necessary policies.  

Historically, the bulk of research into biodiversity has 
been limited to species determination, identification and 
characterization, classification studies. Only recently this 
research turned towards highlighting the potential 
economic value of biodiversity. In recent years, research 
focus has been directed towards the transformation to 
the economic value of biodiversity by biologists, 
environmentalists and economists. This research 
stresses that, to transform the natural world and its 
biodiversity with all its components to a purely economic 
value, it must be supported by a multidisciplinary 



168       Afr. J. Environ. Econ. Manage. 
 
 

 
approach, while taken into consideration conservation 
and sustainable use. Under these conditions, it is seen 
that, economic valuation studies have become 
increasingly important for developing countries which 
have a rich biodiversity. Such approaches underline the 
relevance of policies all set to be transformed to the 
economical value of biological scarce resources. 
Therefore, stricter implementation of both local and 
international economic policies must be maintained to 
ensure the sustainable use of biologically scarce 
resources and the conservation of a regions biodiversity 
for future generations.  

In this context, this research has analysed and 
displayed some key economic valuation studies 
emphasizing the importance of biodiversity with 
qualitative and quantitative sizes. It is clear that, the 
paucity of economic valuation studies plays a limited role 
in the determination of the direct and indirect using value 
of biodiversity, in the determination of the goods and 
services real value is offered by ecosystems and in the 
market analyses. It is important that, the expression of 
total economic value of biodiversity remains stable 
through the use of various economic valuation techniques 
and can thus, be employed in the development of 
applicable economic policies. This research is necessary 
in highlighting where there is a lack of relevant data and 
what manner of economic valuation studies have been 
done so far. It therefore targets which areas and in which 
sectors the valuation of biodiversity is significant.  

Additionally, this research paper focuses on the 
analysis of biodiversity rather than merely natural 
resources, whilst looking into the use of experimental 
studies and the implementable evaluation methods and 
analysis the role played by recent biodiversity policy and 
the management of biodiversity indicators and the value 
information. In this sense, this research will help to 
resolve this relative dearth of valuations within 
biodiversity studies. It is noted that, certain measures be 
taken to allow for the understanding of the economic 
importance of biodiversity and overcoming of this limited 
situation. 
 
 
METHOD 

 
This research is based on an extensive literature evaluation. Some 
published data were collected through the internet from between 
1992 to 2012. The compiled literature was evaluated systematically 
and analytically and classified according to several factors, namely 
goods and service functions of biodiversity, value categories, 
economic valuation methods, the author and year of study, species, 
etc. In the evaluation studies a systematic elimination between the 
similar and consecutive studies was performed.  

The data set obtained was interpreted using “group evaluation 
and descriptive analysis methods”. These value categories are 
used in the measurement of economic value of the provided benefit 
from biodiversity. 
 
(i) The studies that were evaluated according to ecosystem 
functions to the biodiversity; the studies were evaluated regarding 

 
 
 

 
ecosystem functions and services 
(ii) The studies relating to genetic diversity and bio-prospecting   
(iii) The sample research describing biodiversity and the species 
protection; research evaluated a single species in the fauna and 
flora diversity   
(iv) The sample studies that evaluated the protection of natural 
habitat and many species  

 
The identified value categories are shown in tables. These value 
categories are interpreted and discussed analytically and 
systematically in accordance with the results and conclusions 
subsequently reached. 
 
 
FINDINGS AND DISCUSSION 
 
Data related to the findings obtained from the group 
assessment and descriptive analyses, based on the 
literature review, are shown in tables under main titles. 
Further results were obtained through discussion. 
 
Measurement of economic value of the provided 
benefit from biodiversity 
 
Studies and methodologies that were evaluated 
according to ecosystem functions 
 
Within existing economic valuation studies, it is unclear 
whether the focus is towards ecosystems and natural 
sources, and if they refer to biodiversity subjects or not. 
This is primarily due to the fact that, biodiversity is often 
associated with complex ecosystem functions and 
processes and how these can be linked to human 
welfare. Giving an economic valuation to biodiversity has 
proven to be a very difficult issue. Modelling and 
economic analysis of biodiversity comprehends the 
information and indicators of relations between the 
dynamics of ecosystems and the human economic 
activities. Therefore, there is a socio-economic 
relationship with the geographical differentiation of the 
economic valuation studies in biodiversity which further 
complicates implementation. As a result, “the source 
evaluation” and “the biodiversity evaluation” have been 
misused and this situation has led to paucity in research 
on the economic value of biodiversity.  

According to the data gleaned from the literature, 
biodiversity creates various value categories within the 
ecosystem, including the regulation and production of 
habitats and formation function (Table 1). While the 
regulation and habitat value categories constitute indirect 
using values, the production and information function are 
direct use values. Likewise, while such ecosystem 
functions as a gas regulation, climate regulation, water 
reserve, soil control, and biological control constitute 
indirect use values. Value functions such as nutritional 
value, value for use as raw material, genetic and medical 
resource value and aesthetic value constitute the indirect 
using values. Both direct and indirect using values of 
ecosystem functions are evaluated through various 
approaches, including abstention cost, production 



Demir 5379 
Demir              169 
 
 

 
Table 1. Relationship between value functions of biodiversity, value and valuation techniques (Costanzabet al., 1997; White et al., 2004; 
Nunes and Schokkaert, 2003; De Groot et al., 2002, 2010a,b, 2012). 
 

S/N Ecosystem function 
Economic Analysis method 

Values Possible methods  

value $/ha/year that was used  

    
 

 Regulation function     
 

1 Gas regulation 7-265 AC Indirect use RC/CV/GV/FI 
 

2 Climate regulation 88-223 AC Indirect use RC/CV/GV/FI 
 

3 Disruption value 2-7240 AC/RC Indirect use FI/HP/GV 
 

4 Water regulation 2-5445 PD /AC/ FI Indirect use RC/HP/GV 
 

5 Water reserve 3-7600 PD/RC Indirect use AC/FI/TC/HP/CV 
 

6 Soil conservation 29-243 AC/RC Indirect use FI/HP/CV/GV 
 

7 Soil composition 1-10 AC Indirect use RC/FI/CV/GV 
 

8 Nutritional cycle 87-21100 RC Indirect use AC/FI/CV/GV 
 

9 Waste control 58-6696 RC/CV Indirect use AC/FI/HP/GV 
 

10 Pollination 14-25 RC/FI Indirect use DM/CV/GV 
 

11 Biological control 142-195 RC/FI Indirect use AC/CV/GV 
 

 Habitat function     
 

12 Shelter function 3-1523 PD/CV Indirect use, existence value RC/FI/HP/GV 
 

13 Breeding function 142-195 PD Indirect use AC/RC/FI/HP/CV 
 

 Production function     
 

14 Nutritional value 6-2761 PD/ FI/CV Direct consump./option value RC/GV 
 

15 Raw material value 6-1014 PD/ FI/CV Direct consump/option value RC/GV 
 

16 Genetic resource value 6-112 PD/ FI Direct consump/option value RC/CV/GV 
 

17 Medical value 203-3248 PD/ FI Direct consump/option value AC/RC/CV/GV 
 

18 Decorative value 3-145 PD/ FI Direct consumptive use RC/TC/CV/GV 
 

 Information function     
 

19 Aesthetic information 7-1760 HP Direct non-consump use, RC/TC/CV/GV 
 

 function   existence value  
 

20 Recreation and 3-6000 PD/FI/TC/HP Direct non-consump use, RC 
 

 tourism value   existence value  
 

21 Cultural and artistic +++ CV Direct non-consump use DMP/FI/TC/HP/GV 
 

 value     
 

22 Moral and historical 1-25 CV Direct non-consump use, TC/HP/GV 
 

 value   existence value  
 

23 Value of use in +++ CV Direct non-consump use FI/TC/CV/GV 
 

 science/education     
 

 
DMP, Direct market pricing; FI/PF, factor income/production function; AC, avoided cost; RC, replacement cost; HP, hedonic pricing, TC, travel cost; 
CV, contingent valuation; GV, group valuation. 

 

 
function, substitution function, travel cost, conditional 
valuation, and group assessment. As seen in Table 1, the 
quality of the ecosystem, the goods and service function 
and whether ecosystem services have direct market 
value are important factors in determining the method to 
be used in valuation.  

One of the earliest studies to address biodiversity 
according to the value functions of the ecosystem is the 
study conducted by Costanza et al. (1997). Costanza et 
al. (1997) estimated the total value of 23 ecological 
functions to be $33 trillion/year for 17 ecosystems and 16 

 

 
biomes through the use of various valuation techniques. 
It was estimated in the research conducted that, the 
value of the contribution of biodiversity to the nutritional 
cycle was $87 to 21,100/ha/year within the regulation 
function and it was foreseen the most important value 
element was medical resource value within the 
production function value category, which was 203 to 
$3,248/ha/year (Table 1). This shows that, species and 
genetic diversity constitutes a significantly potential value 
in terms of biodiversity. In addition, the value of 
recreation and eco-tourism, which are important value 



170       Afr. J. Environ. Econ. Manage. 
 
 
 

Table 2. Ecosystem functions and service valuation. 
 

Author Value category Study Value ($) 
 
Crossman and Bryan 

Carbon regulation  

(2009)  

 
 

Crossman et al. (2011) Recreation and amenity 
 

value  

 
 

Mullan and Kontoleon Multiple Watershed 
 

(2008) services 
 

Brander et al. (2007) Reef recreation 
 

Costello and Ward (2006) Bioprospecting value 
 

Ricketts et al. (2004) Pollination service 
 

Kaiser and Roumasset 
Watershed conservation  

(2002)  

 
 

Emerton (1999) Water regulation/ 
 

Watershed conservation  

 
 

Laughland et al. (1996) Water reserve value 
 

Turner et al. (1995) Life support value 
 

 
15.8 million-ha study area 
agricultural areas of South 
Australia. 

 
Australia 
 
 
 
 
 
 
 
 
 

 
Tropical forests for coffee 
production in Costa Rica 
 
Mangroes and Wetlands in 
Malaysia and Hawaii 

 
Tropical forest in Mount Kenya 
 

 
Milesburg Pennsylvania 
 
 
Well-watered ecosystems, 
Swedish island 

 
$ 6–120/ha/year 
 

 
$ 1.5-10.2 /ha/year 
 
 
From $ 200/ ha/year to $ 
1,000 /ha/year 
 
$ 184 per visit/year 
 
$ 14/ha -$ 65/ha 

 
$ 361/ha/year 
 
 
$ 845 ha /year-$ 1,022/ 
ha/year 

 
$ 273 ha /year 
 
 
From $ 14 households to 
$ 36 households 

 
From $ 0,4 million to $ 2 
million 

 
Pina (1994) Ecotourism value Mexico From $ 60/day to $ 100/ day 

 
 
 
elements of information function, was estimated to be $3 
to 6,000/ha/year (Table 1). The total of these values is 
defined as the maximization of social benefit obtained 
from biodiversity. The valuation studies in question allow 
for assessing and using biodiversity in an economically 
rational manner as well as better understanding the 
systematic relationships between the ecosystem 
functions.  

The diversity which in the goods and services mobility 
of ecosystem provides the life support systems needed 
for living beings and thus, occurs a critical 
interdependence. This essential interdependence is the 
phenomenon underlying the sustainable development 
approach. This situation plays a vital role in the sharing of 
benefit and to be maximized for social benefits that are 
provided from the goods and services mobility of 
ecosystem. Mullan and Kontoleon (2008) calculated the 
value of the benefit obtained from various watershed 
services to be $200 ha/year and $1,000 ha/year. Costello 
and Ward (2006) evaluated bio-chemicals, natural 
medicine and pharmaceutics ecosystem service flows in 
tropical forests. Marginal value was estimated to range 

 
 
 
between 14/ha to $65/ha. Ricketts et al. (2004), 
calculated the pollination value for coffee production in 
tropical forests as $361 ha/year (Table 2). These figures 
indicate that, the transformation to the economic value of 
ecosystem services allows a clear link to the goods and 
service mobility of biological sources, and to the 
evaluation the ecological, the economic benefit and the 
benefit sharing processes. Thus, the profit and loss 
analysis is done correctly in these subjects. In addition, 
this research gives an evaluation of ecological 
destruction which in turn may cause potential losses to 
ecosystem services. Realization of this situation will 
create an awareness of the biological scarce resources 
which are providing positive added value and 
encouraging sustainable usage. 
 

 
Evaluation of studies into genetic diversity and bio-
prospecting 
 
Bio-prospecting is generally defined as research 
conducted into the genetic codes of living organisms 



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Demir              171 

 
 
 
Table 3. Value of bioprospecting agreements (Nunes and Schokkaert, 2003; Nunes and Nijkamp, 2011). 
 
Parties Study Value 

 

Novartis and Bioamazonia (2007) 10,000 samples of micro-organisms in Brazil $ 4 million 
 

Brazilian Extracta and Glaxo 
30,000 samples from special area of Brazil $ 3,2 million  

Wellcome (1999)  

  
 

Yellowstone National Park and Heat-resistant enzyme; Taq polymerase and bacteria; 
$175, 000  

Diversa (1998) Thermus aqyqticus  

 
 

Inbio and Merck (1991) 2,000 samples from genetic pool of Costa Rica $1 million 
 

 
 

 
(Ding et al., 2007). Genetic diversity which is the input of 
commercial products reflects the willingness of the drug 
industry to finance this research. Marginal value of such 
an input where genetic information is transformed for 
medical purposes corresponds to the added value that it 
brings to the development of health services (Ding et al., 
2007; Costello and Ward, 2006). For instance, effective 
anti-cancer and anti-leukaemia drugs were discovered 
during research conducted on plants by the U.S. National 
Cancer Institute (Craft and Simpson 2001; Nunes et al., 
2003).  

Bio-prospecting agreements concluded between 
governments and drug industries imply the importance of 
financial indicators for such biodiversity values (Artuso, 
2002). The most remarkable of these agreements was 
the incentive launched between Merck and Co. Ltd., the 
biggest drug company of the world, and Instituto National 
de Biodiversidad (INBio) in Costa Rica. When the 
contract was signed in 1991, Merck paid $1 000 000 and 
accepted to pay a royalty fee with the discovery of each 
new product. Subsequently, INBio Bristol-Myers Squibb 
signed contracts with other companies and non-
governmental organisations obtaining genetic resources 
(Ten and Laird, 1999; Nunes et al., 2003; Ding et al., 
2007; Costello and Ward, 2006). A similar agreement 
was signed between Diversa, a biotechnology company 
based in San Dieago, and the U.S. based Yellowstone 
National Park. Diversa accepted to pay $175,000 to 
Yellowstone to conduct bio-technological studies within 
national park spas on heat-resistant micro-organisms 
(Sonner, 1998; Macilwain, 1998; Nunes and Nijkamp, 
2011). Likewise, Brazilian Extracta accepted to pay $3.2 
000 000 to Glaxo Wellcome Company annually for 
30,000 samples consisting of bacteria, fungi, and plants 
(Bonalume and Dixon, 1999; Nunes and Nijkamp, 2011) 
(Table 3). These agreements and the related studies 
indicate that, the economic value of genetic diversity is 
positive.  

In the last century, biological genetic resources have 
become extremely popular with research and 
development laboratories in biotechnology for life science 
and medical companies. Companies, especially big multi-
national corporations are forced to sign up to bio- 

 
 

 
prospecting agreements with many obvious benefits, 
such as the decrease of production process cost, the 
easy process of genetic material, the acceleration of 
production process, and buying power. Particularly, 
modern bio-technology organisms are not evaluated as a 
whole, only being evaluated down to the level of gene. It 
is remarkable that the willingness of the individual to pay 
(WTP) rise of bio-technology and medical companies for 
each gene source and process. From this perspective, all 
living organisms have an economic value and will be 
turned into a commodity. In this respect, gene diversity 
has created the added value and benefit economically. 
However, the WTP values of these companies have 
ignored the potential effect of genetic diversity in the new 
medicine and product development, in the use of plant 
and animal materials. The ethical values and indirect 
values of genetic diversity are not included in the market 
value of contracts. It would therefore be more realistic to 
interpret as the minimum of economic value of genetic 
diversity changing. 
 

 
Case studies on biodiversity and species 
conservation 
 
This study shows that, the economic value of species can 
be measured with all aspects. However, it is determined 
that, the study of species protection is perceived as a 
vital part of the forest ecosystems and wildlife 
ecosystems conservation and it is seen that, the 
economic valuation studies are limited solely to 
biodiversity. The limitation of these studies should be 
perceived as a big problem for the examination of 
biodiversity at the species level (single/multiple). This 
situation is made more difficult with the addition of value 
and indicator information, and understanding ecosystem 
processes and relationships with other species, the 
presentation of real economic value of biodiversity. This 
research has repeatedly stressed that, previous studies 
about this subject have been largely insufficient in their 
scope and conclusions. As research into the economic 
valuation of biodiversity goes into private biodiversity 
areas directly and looks at all factors and components 



172       Afr. J. Environ. Econ. Manage. 
 
 
 

Table 4. Single species valuation in fauna diversity. 
 

Author Study Average WTP calculations 
 

(household/year)  

  
  

Stanley (2005)  
Bandara and Tisdell (2005, 2003) and  
Bandara (2004) 
 
Tisdell et al. (2005a, b) 

Tisdell and Wilson (2004)  
Hsee and Rottenstreich (2004), 

Kontoleon and Swanson (2003) 
 
Horne and Pet¨ajist¨o (2003)  
Cicia et al. (2003)  
Bosetti and Pearce (2003)  
Giraud et al. (2002)  
Macmillan et al. (2002)  
White et al. (2001)  
Bowker and Stoll (1998) 
 
Stevens et al. (1997) 
 
Jakobsson and Dragun (1996)  
Bostedt and Bomen (1996)  
Loomis and Larson (1994) 
 
Loomis and Helfand (1993) 

 
Van Kooten (1993) 

  
Streptocephalus woottoni $24,85 

 

Elephas maximus $ 1,94 
 

Petaurus gracilis $29.88 
 

Dendrolagus bennettianus $53.10 
 

Ailuropoda melanoleuca $ 13.81 
 

Alces alces $145,49 
 

Equus caballus $33,89 
 

Halichoerus grypus $12,83 
 

Eumetopias jubatus $73,83 
 

Anser sp $11,91 
 

Sciurus vulgaris $2,87 
 

Whooping crane conservation From $ 21 to $141 
 

Atlantic salmon restoration in a river, 
From $14,38 to $21,40  

Massachusetts  

 
 

Leadbeater’s possum, Australia $ 29 
 

Wolf conservation in Sweden From 700 SEK to 900 SEK 
 

Gray whale conservation, US From $16 to $18 
 

Conservation of different single $ 13 for sea turtles to $ 25 
 

species, US for Bald eagle 
 

Conservation of water bird’s habitat Sometimes from $ 50 to $ 
 

in wetland, Canada 60 (per ha) 
 

 
 

 
influencing this subject, this insufficiency problem will be 
overcome.  

As the economic valuation studies on plant and animal 
species are collated, it is seen that, the economic value 
studies are more focused on single animal species (Table 
4), whereas single plant species studies have been more 
limited (Table 5). The studies listed with only one animal 
species evaluated are seen on Table 4. The calculations 
were derived from the contingent valuation (CV) practices 
and WTP) was determined to avoid the loss of some 
special species (Venkatachalam, 2004; Stanley, 2005). 
For instance, while Van Kooten (1993) calculated the 
WTP of a water bird living in a wetland in Canada to 
range between 50 and $60 per ha, Stevens et al. (1997) 
determined the restoration value of the Atlantic salmon 
living in a river in Massachusetts to range between 14.38 
and $21.40. In the same way, Stanley (2005), calculated 
that for Streptocephalus woottoni WTP value is 
$24.85/year, Tisdell et al. (2005a, b), for Petaurus gracilis 
WTP value is $29.88/year and Tisdell and Wilson (2004), 
for Dendrolagus bennettianus WTP value is $53.10/year. 
It can be understood and seen from the given examples 
that, the protection value of single species as economical 
is very high in the fauna diversity. 

 
 

 
Table 5 lists the economic valuation studies conducted 

on a single plant species. It is seen that, the economic 
valuation studies on single or multiple species of flora are 
limited both qualitatively and quantitatively in the flora 
diversity which form the first key stage of the ecological 
cycle. Besides, it is evaluated with goods and services as 
a source of timber within the forest ecosystems. This is 
derived from the complex structure of gene sources.  

In studies where various analysis methods were 
employed, functional valuation of single species plant 
diversity was carried out. For instance, Lee (2002) 
analysed the value of orchid production in production 
farms in Taiwan through the method of production 
function and calculated a value of $112,615/year for each 
farmer. In Turkey, Demir (2009) calculated the total value 
for ecosystem functions of Galanthus elwesii as $68/per 
unit/year. The methods of market value, production 
function and conservation prevention cost were used in 
the analysis. Demir (2012) also calculated the medical 
resource value of summer snowflake in Turkey through 
the methods of production function and market analysis 
and estimated medical resource value as $4.5/per 
unit/year for each summer snowflake. When the social 
benefit to gain from the end product to be obtained with 



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Demir              173 

 
 
 
Table 5. Valuation of single species in flora diversity. 
 

Author Study Value  
Demir (2012) 
 
Demir (2009) 

 
Erdem (2006) 
 
Lee (2002) 

 
Medical value in summer snowflake, Turkey  
Total economic value of goods and services related to  
Galanthus elwesii, Turkey 
 
Conservation value of orchid, Turkey  
Economic analysis of orchid production of Taiwan 
production plants, Taiwan 

 
$ 4,5/per unit/year 
 
$ 68 /per unit/year 

 
$ 7 /household/year  
$377,231 / per farm/year and 
$112,615 /per farmer/year 

 

 
Table 6. Studies on conservation of natural habitat and valuation of multiple species. 
 

Author Study Average WTP Calculations (per 
 

household/year)  

  
 

 
Aruoba (2007) 

 
Başak (2003) 

 
Turpie (2003) 
 
Nunes (2002) 
 
Roosen et al. (2001), 
Région Wallonne (2001) 
 
Wiestra (1996) 
 
Jakobsson and Dragun (1996b)  
Richer (1995)  
Brouwer (1995) 
 
Carson et al. (1994) 

 
Hoevenagel (1994) 

 
Value of Ecological Services of Yumurtalık Wetland,  
Turkey 
 
Tuz Lake Specially Protected Area, Central Anatolia,  
Turkey 
 
Conservation of South African biodiversity, fynbos 
biome in the Western Cape, for national biodiversity 
 
Conservation of natural parks and wilderness areas 
 
Conservation value for Rouge de Belgique Cattle 
breeds and 5 different sheep breeds, Belgium 
 
Conservation of ecological agricultural fields, the 
Netherlands 
 
Conservation of all endangered species in 
Victoria Desert conservation in California  
Conservation of marshy pasture areas 
 
Kakadu conservation region and natural 
park conservation, Australia 
 
Improving wild life habitat in marshy pasture areas in 
Germany, the Netherlands 

 
$ 738 /ha/year 

 
$ 678,33/ha/year (Total value) 

 
$ 8,4 million /year, $ 3,3 
million/year,$ 58 million/year 
 
From  $ 40 to $ 51  
€ 120 /Subsidy/animal/year and   
€ 20 /Subsidy/animal/year  

 
NLG 35 (single-limited) 

 
$118 

$101  
From NLG 28 to NLG 72  
$ 52 (little influence scenario) 
$ 80 (big influence scenario) 
 
From NLG 16 to NLG 46 

 
Desvousges et al. (1993) 

Whitehead (1993) 
 
Duffield and Patterson (1992) 

 
Halstead et al. (1992) 

 
Conservation of immigrant water birds in Central Flyway From $ 59 to $ 71  
Nongame wild life conservation program $ 15 

 

Fishery conservation in Montana Rivers From $ 2 to $ 4 (for the residents), 
 

from $ 12 to $17 (for nonresidents)  

 
 

Conservation of bald eagle, jackal and wild turkey in 
$ 15  

England  

 
 

 
 
 
the processing of these plants is included in these values, 
the resulting added value will be even higher. The 
increase in the quality and quantity of studies of this area 
will be a guide to a more holistic understanding of the 
roles of plant species within an ecosystem. 

 
Case studies on conservation of natural habitat and 
on evaluation multiple species 
 
Some studies prefer associating the value of biodiversity to 

 
 
 
the value of conservation of natural habitat. Case studies 
conducted in this respect are given in Table 6. For 
instance, Nunes (2002) conducted the first national CV 
application in Portugal, carried out a WTP evaluation for 
the conservation of natural parks and wilderness areas 
and obtained an average WTP ranging between 40 and 
$51. Besides, a CV study was conducted by Bateman et 
al. (1992) to evaluate the financial value of conserving 
the Norfolk Broads. The results showed that, the 
residents of the Norfolk Broads had a WTP value of 



174       Afr. J. Environ. Econ. Manage. 
 
 

 
£12 while those living in different regions of UK had a 
WTP value of £4 (Table 6). Hoevenagl (1994) carried out 
a WTP research by telling 127 farmers in the pasture 
areas in Germany that they would receive grants from the 
government on condition that they used their fields in a 
manner benefitting the habitat of wild animals. The 
assessment revealed an average WTP ranging between 
NLG 16 and NLG 45. Kealy and Turner (1993) calculated 
the WTP value of the benefit obtained from conserving 
Adirondack aquatic system to range between 12 and $18. 
Siberman et al. (1992) examined the current value of 
coast ecosystems for users and non-users of New Jersey 
coasts. The average WTP was found as $15.1 for users 
while it was found as $9.26 for non-users. Lastly, 
Halstead et al. (1992) calculated the WTP value for 
conserving Bald eagle, jackal and wild turkey in New 
England as $15.  

When comparing multi-species and single species 
research, multi-species WTP values are significantly 
higher. The problem in the value account interpretation of 
species or habitat conservation is the missing connection 
between a special species or habitat and habitats in need 
of conservation. This is the primary difficulty in the 
economic value analysis of species and habitats. 

 
Conclusion 
 
In this study biodiversity was analyzed at different levels: 
the ecosystem and its functions, genetic diversity and bio-
prospecting, species and habitats showing that, 
biodiversity should be evaluated using an interdisciplinary 
approach. In this way, biodiversity has been formulated 
with the other different components and has been 
transformed to an economic value using the various 
valuation methodologies.  

In addition, the economic value of biodiversity is 
Affected and changed according to the level of diversity in 
habitat, the type of value, the applied valuation method, 
the geographic location and socio-economic structure. 
 

The main question which needed answering through 
this research was ‘how can we use the present research 
to formulate an integrated and effective framework to 
determinate the value of biodiversity?’ The answer to this 
question requires that, a clear life diversity level be 
chosen, a concrete biodiversity changing scenario to be 
formulated, the biodiversity within certain boundaries, and 
at last, having a particular perspective on the value of 
biodiversity. It was shown that, most economical studies, 
using the monetary valuation have actually confused 
biodiversity with biological resources. This situation has 
lead to a dearth of studies focused principally on 
biodiversity. Additionally, it seems clear that in our 
assessment of economic valuation studies, the evaluation 
of biodiversity values does not give a stable or clear 
monetary value for biodiversity. Therefore, it should be 
accepted that, the economic valuation studies have an 

 
 
 

 
inadequate perspective for the unknown value of 
biodiversity changes and obtained economic values and 
indicators are considered as a lower limit.  

To reiterate, the economic valuation estimates should 
be regarded as providing a very incomplete perspective 
on, and at the best lower bounds to the unknown value of 
biodiversity changes. However, it should be given a place 
to “the integrated ecological and economic models”. The 
integrated models can bring out several biological and 
economic (possibly monetary) indicators which are 
collected via the multi-criteria analysis techniques. It is 
possible to provide for a closer, innovative connection 
between modelling and valuation, among other methods, 
by generating conditional values for specific 
environmental-economic scenarios; using scenario-
modelling outcomes such as tables and graphs in 
valuation experiments (e.g., contingent valuation) and 
using spatial models to aggregate monetary values 
related to specific areas.  

To date, most studies lack a uniform and clear 
perspective on biodiversity as a distinct, univocal 
concept. This situation is explained by many reasons. 
First reason is that, insufficient information exists on the 
quantity of species and the genetic variations within 
species. Secondly, it is not known exactly the population 
analysis and the genetic variation value of species in a 
population. Thirdly, the numerous functions among 
ecosystems and the value of interrelation diversity that 
occurs in the different ecosystems have not been fully 
taken into account. Finally, the significant differing degree 
in the similar assets on the global level, the biodiversity 
values because of the unequal international income 
distribution. In order to determine unequivocally the total 
economic value of biodiversity, we should remove these 
obstacles.  

In conclusion, the available economic valuation 
estimates should be considered, at best, as a lower 
bound to an unknown value of biodiversity, and are 
always contingent upon the available scientific 
information as well as their global socio-economic 
context. As we have seen, biodiversity can be dealt with 
at different levels: genetic, species, ecosystem, and 
functional diversity. For the analysis and valuation of 
biodiversity at the ecosystem and functional levels, which 
may be regarded as the cornerstone of the analysis and 
valuation of biodiversity, an active interdisciplinary 
dialogue is necessary, with emphasis on the complex 
interface between natural science and social science 
disciplines.  

A comprehensive assessment of ecosystem 
biodiversity characteristics, structure, and functioning 
requires the analyst to take various important steps. 
Firstly, the socio-economic causes and consequences of 
biodiversity degradation or loss should be determined. 
Secondly, the negative impacts on biodiversity caused by 
human activities should be assessed. The range and 
degree of biodiversity functioning should be estimated, 



Demir              175 
 
 

 
especially in terms of ecosystem-functional relationships. 
Finally, alternative biodiversity management strategies 
should be ranked and a joint spatial and temporal 
systems analysis of each policy scenario should be 
undertaken. However, the physical assessment of the 
functions performed by biodiversity is an essential 
prerequisite to any ecological evaluation. Thus, simply 
identifying functions will be insufficient if we want to 
present resource managers and policymakers with 
relevant policy response options. Valuation criteria for the 
function evaluations of species such as computer 
modelling, geographical information systems (GIS), Red 
Data Species Lists and the biological value indexes must 
be further developed. This in turn will lead to evaluations 
in terms of the value of biodiversity, providing input to the 
production process, the effects on the regulation of 
human welfare and ecological functions. This approach to 
ecological evaluation allows for a direct comparison of 
management or conservation strategies.  

Economists, the ecologists, and other vested interests 
must work together using integrated approaches for a 
clearer understanding of the importance of these studies. 
Only in this way can we expect full social benefit-sharing, 
together with effective and useful policy implementation. 
The significance of these studies is far greater for those 
responsible countries that strive to protect the rich 
biological diversity that remains. 
 
 
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