Gain and loss: Human and environmental wellbeing – drivers of Kilimanjaro’s decreasing biodiversity

There was also a strong negative correlation between number of Red List species and population density, with a clear decreasing trend over time (Fig 9C), resulting in many wards without any endangered species in 2022. IUCN Red List species (26 species in the study area) occurred only in forest and savanna habitats (Table 2), which are ecosystems with a strong decrease since 1976 (Figs 5 and 6). The relatively high number of Red List species at the highest population density of 3500 people/km2 is due to the presence of Rau Forest Reserve located in Moshi Municipal. Introduced invasive species are significant threats to biodiversity worldwide [2] and in Tanzania [73], where 67 inva- sive species have severe negative impacts on local ecosystems habitats and native species. Our dataset records 180 introduced species on Kilimanjaro, including cultivated plants; however, only a few, such as Prosopis juliflora, Tecoma stans, Caesalpinia decapetala, Calliandra houstoniana, Parthenium hysterophorus (causing allergies) and Lantana camara, are invasive and problematic, particularly in disturbed savanna and submontane areas, whereas Acacia mearnsii affects the former half-mile forest strips. A preliminary study (Hemp unpub. data) documented the spread of Prosopis juli- flora since 1990, which now occupies 7% of the area shown in Fig 10 and is spread by livestock [74]. The other mentioned invasive species have (up to now) not significantly impacted Kilimanjaro’s ecosystems. Similarly, Jaureguiberry et al. [14]

noted that, in recent decades, invasive alien species have been less important causes of global biodiversity loss, espe- cially in Africa, compared to land-use change. In this study, neophytes are viewed not as a factor influencing biodiversity, but as a (partly negative) part of it as a consequence of land cover change. Fig 9D shows the positive correlation between population density and neophyte numbers per km2. Our dataset includes 180 introduced species, representing about 9% of the total species. At 1000 people/km2, neophytes numbered approx- imately 109 in 1976, rising to 117 by 2002 and 128 in 2022, reflecting a decline in natural vegetation (Fig 4). The very weak and non-significant correlation in 2022 may be due to more open agriculture being converted into homegardens, which hold the highest number of introduced species on Kilimanjaro, with over 100 cultivated plants originating from out- side Africa [53] (Table 2). Therefore, the density of introduced species peaked in rural areas rather than densely populated urban areas in 2022. The increasing trend of neophytes may be stronger than reported, as our data cannot capture their immigration over time (see “critical remarks” in Supplementary Informations S1 Text). Increased tourism also raises the risk of introducing exotic plant species, especially in Kilimanjaro’s upper zones. One such species, Poa annua, a European-origin weed, is found on roadsides and pastures. Like most other neophytes on Kilimanjaro, Poa annua invades only anthropogenic or

disturbed vegetation, occurring between about 1600 and 4000 m asl. along climbing routes or their vicinity. Its spread has paralleled the rise in climbing tourism over the past 30 years [32], though an invasion of natural vegetation types seems unlikely at present.

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 18 / 23 The importance of nature conservation for the protection of biodiversity The study area includes three forest reserves south of Moshi, with only Rau forest largely intact, while the others face near-total destruction, highlighting the importance of effective management in conservation to mitigate population growth’s negative effects on biodiversity. Rau Forest Reserve is increasingly attracting tourists, providing economic incentives for nature conservation in an area rich in endemic species that are found nowhere else. The value of such reserves is clear from Fig 10, based on Hurskainen et al. [75]. In a 1300 km2 area on Kiliman- jaro’s southern foothills (mainly within the study area, Fig 1), only 29% maintained semi-natural vegetation, with just 3% as forests in 2012. Fig 10, right panel shows species richness at 1-hectare grids; cultivated ecosystems have low species numbers, especially in high-intensity land use types like sugar cane plantations and rice fields. In contrast, Rau Forest and Namalok, a private nature reserve (see below) exhibit high species richness (84–100 species per hectare). Additionally, the critical role of riparian areas in connecting lowlands and highlands as biodiversity “blood vessels” is evident. Another large nature reserve is Namalok. Located in the southern part of the study area (Fig 1), this reserve covers 46 km2 and is owned by the semi-private/state-owned sugarcane company TPC. Initial efforts to conserve this area began in

2005 and it was fenced off in 2010. Due to its remoteness, in 1976 78% was still covered by natural vegetation (riverine forests, savanna woodlands and alkaline grasslands) and by 2022 this had increased to 100%. In recent years, antelopes and zebras have been reintroduced and the reserve is now open to tourists. Conclusions The lack of plant abundance data in our approach limits the application of diversity indices such as Shannon and even- ness metrics. Instead, we focus on species richness, the simplest and most appropriate measure of diversity [76,77], but also on species composition. We therefore address a very significant aspect of biodiversity. Fig 10. Land use and related species richness on the southern foothills of Kilimanjaro. Left: LULC map (2012) of the southern foothills of Kiliman- jaro with Moshi in the centre (compiled from Hurskainen et al. 2019 [75]), right: Mean species richness at 1 ha grid. High land use intensity resulted in low diversity, whereas protected areas harboured a high biodiversity. For more details and location of the study area see Supplementary Information S1 Text and Fig 1. https://doi.org/10.1371/journal.pone.0334184.g010

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 19 / 23 Climate change had no apparent impact on biodiversity trends in the densely populated lower regions of Kilimanjaro over the past 40 years. The primary factor negatively affecting biodiversity is land use change driven by rapid population growth and economic development that leads to increased land-use intensity replacing native biodiversity with agricultural species and ecosystems. To our knowledge, this study is the first to link human population densities with plant species densities at a 1 km2 scale in a tropical region, utilizing remote sensing data alongside a comprehensive dataset of the species on the ground. This approach enabled us to analyze various plant groups of different environmental importance and not only simple total species numbers for more ecologically meaningful diversity trends. We also cleaned our dataset to avoid multiple counts of species, requiring sufficient ground data on species composition across the different vegetation types present. For this approach, extensive ecological field data are crucial, often not considered or not available. This makes it difficult to transfer this approach to other tropical regions. Furthermore, it highlights the importance of biological col- lections, which enable the identification and storage of collected specimens. Without the collections and taxonomists of the herbaria in Nairobi, Kew, Paris, Vienna, Oslo, Copenhagen, Berlin, Stockholm, Uppsala and Arusha, this study would not have been possible.

The declining trends in certain natural habitats would have been more pronounced if we could distinguish vegetation types at a finer scale; however, older remote sensing data limited this accuracy. For instance, wetlands – important hab- itats for birds on Kilimanjaro – have probably lost over 90% of their area in recent decades due to illegal water pumping and conversion to rice paddies, often abandoned after a few years due to salinization. Most lower slopes of Kilimanjaro were already converted to anthropogenic land use by 1976, at the start of our detailed evaluation. A century ago, when Kilimanjaro’s population was below 100,000, approximately 98% of its savanna vegeta- tion remained intact, and natural vegetation covered 90% of the lower slopes. Although biodiversity data from that time is limited, extrapolating our population density and species richness trends suggests that in 1911, nearly 700 native plant species existed per km2, whereas today, this number has declined to approximately 180. If we consider population density and economic prosperity as indicators of human well-being [6,78] and the area of natural habitats and species counts as indicators of ecological well-being, we can see significant gains in human well-being alongside strong declines for environ- mental well-being at Kilimanjaro in recent decades. However, land degradation from poor management, such as wetland destruction and invasion by non-native species due to overgrazing former habitats of iconic animals such as elephants, giraffes and lions, threatens both the environment

and long-term human well-being, despite current economic growth. For instance, asthma rates have reportedly increased on Kilimanjaro, possibly due to the replacement of permanent vegetation with fields, raising dust and allergen levels, especially during the dry seasons and exacerbated by the spread of allergenic invasive species such as Parthenium in disturbed areas. On the positive side, as a combination of ecological and human well-being, the development of sustainable traditional agroforestry through the conversion of degraded land, the protection of the Rau forest compared to poorly managed reserves and the establishment of protected areas like Namalok are potential strategies to mitigate drastic changes in land cover. Chagga homegardens stand out as a model for sustainable agricultural practices in tropical regions, showcasing land use without soil degradation or erosion for centuries. Furthermore, effective management of Kilimanjaro National Park, which provides essential ecosystem services, benefits the local population. The Namalok nature reserve, which is since 2010 protected from overgrazing by cattle, also provides space for large animals, while the local population benefits from the renewable forests as they are allowed to collect the now abundant firewood. Kilimanjaro remains a biodiversity hotspot, reflecting both the extraordinary diversity of its flora and vegetation and the challenges posed by demographic and ecological changes, exemplifying broader issues and opportunities for other tropi- cal regions.

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 20 / 23 Supporting information S1 Table. Species numbers and reduction factors for all LULC-combinations. (XLSX) S1 Text. Supplementary information for “Drivers of Kilimanjaro’s decreasing biodiversity”. (DOCX) S1 Checklist. Additional information regarding the ethical, cultural, and scientific considerations specific to inclusivity in global research. (DOCX) Acknowledgments We thank the Tanzania Commission for Science and Technology (COSTECH), the Tanzania National Parks (TANAPA) and the Tanzania Wildlife Research Institute (TAWIRI) for permitting research. Author contributions Conceptualization: Andreas Hemp. Data curation: Andreas Hemp. Formal analysis: Andreas Hemp, Mieko Miyazawa, Pekka Hurskainen. Funding acquisition: Andreas Hemp. Investigation: Andreas Hemp. Methodology: Andreas Hemp. Project administration: Andreas Hemp. Writing – original draft: Andreas Hemp, Mieko Miyazawa, Pekka Hurskainen. Writing – review & editing: Andreas Hemp, Mieko Miyazawa, Pekka Hurskainen. References 1. Steffen W, Richardson K, Rockström J, Cornell SE, Fetzer I, Bennett EM, et al. Sustainability. Planetary boundaries: guiding human development on a changing planet. Science. 2015;347(6223):1259855. https://doi.org/10.1126/science.1259855 PMID: 25592418 2. IPBES. Summary for policymakers of the global assessment report on biodiversity and ecosystem services. Bonn: Intergovernmental Science- Policy Platform on Biodiversity and Ecosystem Services; 2019.

Trans R Soc Lond B Biol Sci. 2020;375(1794):20190104. https://doi.org/10.1098/rstb.2019.0104 PMID: 31983329

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 21 / 23 11. Sala OE, Chapin FS 3rd, Armesto JJ, Berlow E, Bloomfield J, Dirzo R, et al. Global biodiversity scenarios for the year 2100. Science. 2000;287(5459):1770–4. https://doi.org/10.1126/science.287.5459.1770 PMID: 10710299 12. Pereira HM, Navarro LM, Martins IS. Global biodiversity change: the bad, the good, and the unknown. Annu Rev Environ Resour. 2012;37(1):25– 50. https://doi.org/10.1146/annurev-environ-042911-093511 13. Maxwell SL, Fuller RA, Brooks TM, Watson JEM. Biodiversity: the ravages of guns, nets and bulldozers. Nature. 2016;536(7615):143–5. https:// doi.org/10.1038/536143a PMID: 27510207 14. Jaureguiberry P, Titeux N, Wiemers M, Bowler DE, Coscieme L, Golden AS, et al. The direct drivers of recent global anthropogenic biodiversity loss. Sci Adv. 2022;8(45):eabm9982. https://doi.org/10.1126/sciadv.abm9982 PMID: 36351024 15. Mottet A, Ladet S, Coqué N, Gibon A. Agricultural land-use change and its drivers in mountain landscapes: a case study in the Pyrenees. Agric Ecosyst Environ. 2006;114:296–310. 16. Bucała A. The impact of human activities on land use and land cover changes and environmental processes in the Gorce Mountains (Western Polish Carpathians) in the past 50 years. J Environ Manage. 2014;138:4–14. https://doi.org/10.1016/j.jenvman.2014.01.036 PMID: 24565936 17. Hemp A. Ecology of the pteridophytes on the southern slopes of Mt. Kilimanjaro. Part II: Habitat Selection. Plant Biol. 2001;3(5):493–523. https:// doi.org/10.1055/s-2001-17729

18. Classen A, Peters MK, Ferger SW, Helbig-Bonitz M, Schmack JM, Maassen G, et al. Complementary ecosystem services provided by pest preda- tors and pollinators increase quantity and quality of coffee yields. Proc Biol Sci. 2014;281(1779):20133148. https://doi.org/10.1098/rspb.2013.3148 PMID: 24500173 19. Bianco G, Manning P, Schleuning M. A quantitative framework for identifying the role of individual species in Nature’s Contributions to People. Ecol Lett. 2024;27(2):e14371. https://doi.org/10.1111/ele.14371 PMID: 38361471 20. Hemp A. Climate change‐driven forest fires marginalize the impact of ice cap wasting on Kilimanjaro. Glob Chang Biol. 2005;11(7):1013–23. https://doi.org/10.1111/j.1365-2486.2005.00968.x 21. Hemp A, Hemp C. Broken bridges: the isolation of Kilimanjaro’s ecosystem. Glob Chang Biol. 2018;24(8):3499–507. https://doi.org/10.1111/ gcb.14078 PMID: 29504230 22. Myers N, Mittermeier RA, Mittermeier CG, da Fonseca GA, Kent J. Biodiversity hotspots for conservation priorities. Nature. 2000;403(6772):853–8. https://doi.org/10.1038/35002501 PMID: 10706275 23. Hemp A. Vegetation of Kilimanjaro: hidden endemics and missing bamboo. Afr J Ecol. 2006;44(3):305–28. https://doi. org/10.1111/j.1365-2028.2006.00679.x 24. B JPM. Some aspects of the phytogeography of tropical Africa. Ann Mo Bot Gard. 1978;65(2):437–78. 25. Soini E. Land use change patterns and livelihood dynamics on the slopes of Mt. Kilimanjaro. Agric Syst. 2005;85:306–23.

26. Lambrechts C, Woodley B, Hemp A, Hemp C, Nnyiti P. Aerial survey of the threats to Mt. Kilimanjaro forests. Dar es Salaam: UNDP; 2002. 27. Maeda EE, Hurskainen P. Spatiotemporal characterization of land surface temperature in Mount Kilimanjaro using satellite data. Theor Appl Clima- tol. 2014;118(3):497–509. https://doi.org/10.1007/s00704-013-1082-y 28. Hemp A, Oleson E, Buchroithner MF. Kilimanjaro. Physiographic map with landuse and vegetation, scale 1:100,000. München, Germany: ARGE; 2017. 29. Hemp A, Zimmermann R, Remmele S, Pommer U, Berauer B, Hemp C. Africa’s highest mountain harbours Africa’s tallest trees. Biodivers Conserv. 2017;26:103–13. 30. Hemp C. The Chagga home gardens: relict areas for endemic saltatoria species (Insecta: Orthoptera) on Mt. Kilimanjaro. Biodivers Conserv. 2005;125:203–10. 31. Hemp A. The banana forests of Kilimanjaro. Biodiversity and conservation of the agroforestry system of the Chagga Homegardens. Biodivers Con- serv. 2006;15(4):1193–217. 32. Hemp A. Introduced plants on Kilimanjaro: tourism and its impact. Plant Ecol. 2007;197(1):17–29. https://doi.org/10.1007/s11258-007-9356-z 33. Hemp C, Hemp A. Saltatoria coenoses of high-altitude grasslands on Mt. Kilimanjaro, Tanzania (Orthoptera: Saltatoria). Ecotropica. 2003;9:71–97. 34. Müller MJ. Handbuch ausgewählter Klimastationen der Erde. 3 ed. Mertesdorf, Ruwertal (Trier): Forschungsstelle Bodenerosion der Universität Trier; 1983. 35. Hemp A, Hemp J. Weather or not—global climate databases: reliable on tropical mountains? PLoS ONE. 2024;19(3):e0299363.

36. Otte I, Detsch F, Mwangomo E, Hemp A, Appelhans T, Nauss T. Multidecadal trends and interannual variability of rainfall as observed from five lowland stations at Mt. Kilimanjaro, Tanzania. J Hydrometeorol. 2016;18:349–61. 37. Raum J. Statistisches aus dem Dschaggalande. Evangelisch-lutherisches Missionsblatt. 1914. pp. 124–7. 38. Pesaresi M, Politis P. GHS-BUILT-S R2023A - GHS built-up surface grid, derived from Sentinel2 composite and Landsat, multitemporal (1975- 2030). European Commission Joint Research Centre PID: 2023. http://data.europa.eu/89h/9f06f36f-4b11-47ec-abb0-4f8b7b1d72ea 39. Exavier R, Zeilhofer P. OpenLand: software for quantitative analysis and visualization of land use and cover change. R J. 2020;12(2):359. https:// doi.org/10.32614/rj-2021-021 40. Sprigade P, Moisel M, Verlag ES. Hans Meyer’s Ostafrika-Expedition [map]. 1911. Available from: https://www.loc.gov/item/2009578555/

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 22 / 23 41. Meyer H. Ostafrikanische Gletscherfahrten. Forschungsreisen im Kilimandscharo-Gebiet. Leipzig: Duncker & Humblot; 1890. 42. Volkens G. Der Kilimandscharo: Darstellung der allgemeineren Ergebnisse eines fünfzehnmonatigen Aufenthalts im Dschaggalande. Berlin: Reimer; 1897. 43. Jaeger F. Forschungen in den Hochregionen des Kilimandscharo. Mitteilungen aus den Deutschen Schutzgebieten. 2023;22(1090):113–46, 161–96. 44. Klute F. Ergebnisse der Forschungen am Kilimandscharo 1912. Berlin; 1920. 45. Arrhenius O. Species and area. J Ecol. 1921;9:95–9. 46. Rosenzweig ML. Species diversity in space and time. Cambridge: Cambridge University Press; 1995. 47. Drakare S, Lennon JJ, Hillebrand H. The imprint of the geographical, evolutionary and ecological context on species-area relationships. Ecol Lett. 2006;9(2):215–27. https://doi.org/10.1111/j.1461-0248.2005.00848.x PMID: 16958886 48. Hemp A, Del Fabbro C, Fischer M. Area modulates the effect of elevation but not of land use or canopy on tropical plant species richness. Biodiv- ers Conserv. 2021;30(14):4265–77. https://doi.org/10.1007/s10531-021-02304-6 49. National Bureau of Statistics Tanzania. General Information. 2024. [cited 2024 Mar 13] Available from: https://www.nbs.go.tz/?utm_source=chatgpt. com 50. United Nations. World Population Prospects 2024: Summary of Results. New York: UN DESA/POP; 2024. 51. World Population Review. Tanzania Population. Available from: http://worldpopulationreview.com/countries/tanzania-population/

52. Swynnerton RJM. Some Problems of the Chagga on Kilimanjaro. East Afr Agric J. 1949;14(3):117–32. https://doi.org/10.1080/03670074.1949.1166 4670 53. Hemp A, Hemp C, Winter JC. Environment and worldview: the Chagga homegardens. Culture, history and identity: landscapes of inhabitation in the Mount Kilimanjaro Area, Tanzania. Essays in honour of Paramount Chief Thomas Lenana Mlanga Marealle II (1915-2007). Oxford: Archaeo- press; 2009. pp. 235–303. 54. Twisa S, Buchroithner MF. Land-Use and Land-Cover (LULC) Change Detection in Wami River Basin, Tanzania. Land. 2019;8(9):136. https://doi. org/10.3390/land8090136 55. IMF. GDP per capita, current prices – Tanzania. IMF Datamapper. 2024. [cited 2024 May 29]. Available from: https://www.imf.org/external/datamap- per/NGDPDPC@WEO/TZA?zoom=TZA&highlight=TZA 56. OECD, Sahel and West Africa Club Secretariat, African Development Bank, United Nations Economic Commission for Africa. Africa’s Urbanisation Dynamics 2025: Planning for Urban Expansion. Paris: OECD Publishing; 2025. 57. Hemp A, Bianco G, Pócs T. Homegardens and coffee plantations on Kilimanjaro: refugium for bryophytes in densely cultivated landscapes. Hatto- ria. 2023;14(1):1–16. 58. IPCC. Climate Change 2014: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the IPCC. Cam- bridge: Cambridge University Press; 2014. 59. Mölg T, Großhauser M, Hemp A, Hofer M, Marzeion B. Limited forcing of glacier loss through land-cover change on Kilimanjaro. Nat Clim Chang. 2012;2:254–8. https://doi.org/10.1038/nclimate1425

60. Hemp A. The impact of fire on diversity, structure, and composition of the vegetation on Mt. Kilimanjaro. Land use change and mountain biodiver- sity. Boca Raton: CRC Press; 2005. pp. 51–68. 61. Abera TA, Heiskanen J, Maeda EE, Muhammed MA, Bhandari N, Vakkari V, et al. Deforestation amplifies climate change effects on warming and cloud level rise in African montane forests. Nat Commun. 2024;15(1):6992. https://doi.org/10.1038/s41467-024-51324-7 PMID: 39143071 62. Pepin NC, Duane WJ, Hardy DR. The montane circulation on Kilimanjaro, Tanzania and its relevance for the summit ice fields: Compari- son of surface mountain climate with equivalent reanalysis parameters. Glob Planet Change. 2010;74(2):61–75. https://doi.org/10.1016/j. gloplacha.2010.08.001 63. Cardinale BJ, Duffy JE, Gonzalez A, Hooper DU, Perrings C, Venail P, et al. Biodiversity loss and its impact on humanity. Nature. 2012;486(7401):59–67. https://doi.org/10.1038/nature11148 PMID: 22678280 64. Marques A, Martins IS, Kastner T, Plutzar C, Theurl MC, Eisenmenger N, et al. Increasing impacts of land use on biodiversity and carbon seques- tration driven by population and economic growth. Nat Ecol Evol. 2019;3(4):628–37. https://doi.org/10.1038/s41559-019-0824-3 PMID: 30833755 65. Tscharntke T, Klein AM, Kruess A, Steffan-Dewenter I, Thies C. Landscape perspectives on agricultural intensification and biodiversity–ecosystem service management. Ecol Lett. 2005;8:857–74.

66. Jetz W, Wilcove DS, Dobson AP. Projected impacts of climate and land-use change on the global diversity of birds. PLoS Biol. 2007;5(6):e157. https://doi.org/10.1371/journal.pbio.0050157 PMID: 17550306 67. Lovett JC, Hemp A. Is climate change making plants go up mountains? Front Biogeogr. 2010;2(1):4−5. 68. Peters MK, Hemp A, Appelhans T, Behler C, Classen A, Detsch F, et al. Predictors of elevational biodiversity gradients change from single taxa to the multi-taxa community level. Nat Commun. 2016;7:13736. https://doi.org/10.1038/ncomms13736 PMID: 28004657 69. Mollel NP, Fischer M, Hemp A. Usable wild plant species in relation to elevation and land use at Mount Kilimanjaro, Tanzania. Alp Botany. 2017;127(2):145–54. https://doi.org/10.1007/s00035-017-0187-9

PLOS One | https://doi.org/10.1371/journal.pone.0334184 October 29, 2025 23 / 23 70. UNDP, UNEP, World Bank, WRI. A guide to world resources 2000–2001: People and ecosystems: the fraying web of life. Washington, DC: UNDP, UNEP, World Bank, WRI; 2000. 71. Zhou Y. Smallholder mapping II: Trends in demographics and driving forces. Basel: Syngenta Foundation for Sustainable Agriculture; 2011. 72. Hedberg O. The phytogeographical position of the afroalpine flora. Recent Adv Bot. 1961;1:914–9. 73. United Republic of Tanzania. Fifth national report on the implementation of the Convention on Biological Diversity. Dar es Salaam: Vice President’s Office, Division of Environment; 2014. 74. Alvarez M, Heller G, Malombe I, Matheka KW, Choge S, Becker M. Classification of Prosopis juliflora invasion in the Lake Baringo basin and envi- ronmental correlations. Afr J Ecol. 2019;57:296–303. 75. Hurskainen P, Adhikari H, Siljander M, Pellikka PKE, Hemp A. Auxiliary datasets improve accuracy of object-based land use/land cover classifica- tion in heterogeneous savanna landscapes. Rem Sens Environ. 2019;233:111354. https://doi.org/10.1016/j.rse.2019.111354 76. Whittaker RH. Evolution of species diversity in land communities. Evol Biol. 1977;10:1–87. 77. Gentry AH. Changes in plant community diversity and floristic composition on environmental and geographical gradients. Ann Mo Bot Gard. 1988;75:1–34. 78. Jordan SJ, Hayes SE, Yoskowitz D, Smith LM, Summers JK, Russell M, et al. Accounting for natural resources and environmental sustainability:

linking ecosystem services to human well-being. ACS Publications; 2010.