Assessing national human footprint and implications for biodiversity conservation in Iran

Abstract

Recent global-scale studies have revealed intense levels of human activities within many protected areas worldwide. However, these analyses rely on coarse global-scale data, making their utility for informing local-scale conservation action limited. We developed a spatially explicit national human footprint index for Iran, a biologically diverse country in west Asia, based on the latest high-resolution datasets available for human pressures. We assessed the extent and intensity of human pressure within Iranian protected areas, and across the biomes and ecoregions of Iran. We found that almost one-quarter (22%) of officially protected land was under intense human pressure, mostly located in north-west and west of the country. Protected areas within temperate grasslands, savannas, and shrublands are most impacted, with two-third of their area under intense pressure. The findings provide valuable information for targeting management strategies to alleviate human pressures within protected areas, and also act as a comprehensive database to track the state of protected areas through time.

Electronic supplementary material

The online version of this article (10.1007/s13280-019-01305-8) contains supplementary material, which is available to authorized users.

Introduction

Human activities negatively impact biodiversity worldwide, driving extinctions (Dirzo and Raven 2003), species population declines (Ceballos et al. 2015), and degradation of ecosystem services and functions (MEA 2003; Di Giulio et al. 2009; Butchart et al. 2010; Hunter et al. 2010; Kuriqi et al. 2017). An increasing human population means that demand for natural resources continues to grow, making the conservation of natural areas challenging (Butchart et al. 2010). Understanding the pattern of human impacts on the natural environment is therefore crucial for targeting management strategies and actions to conserve biodiversity (Venter et al. 2016).

Over the last two decades, there has been substantial effort put into assessing human impact on the environment, through mapping and measuring human influence on species and habitats at different spatial extents (Sanderson et al. 2002; Venter et al. 2016). These approaches generally combine multiple measures of human impacts, such as agriculture, roads, and human population density, into single indices representing human pressure on the environment. The first global human footprint was developed by Sanderson et al. (2002), combining data on multiple human pressures including roads, urban areas, and livestock grazing. Further studies used cumulative global threat maps to assess human impacts on the ocean Halpern et al. (2008), while others assessed how terrestrial human footprint was changing inside conservation areas (Geldmann et al. 2014). Most recently, Venter et al. (2016) used the human footprint framework developed by Sanderson et al. (2002) to calculate how terrestrial human footprint had changed between 1993 and 2009. The findings from the human footprint maps have been directly linked to biodiversity declines (Newbold et al. 2015), increases in species extinction risk (Di Marco et al. 2018), and decreases in species movement (Tucker et al. 2018). As such, human footprint maps are increasingly used to assess the success of conservation efforts such as protected areas, which are intended to prevent or slow the increase of human activities that impact biodiversity.

Protected areas are the cornerstones of biodiversity conservation efforts, and the global protected area estate has roughly doubled in size since the early 1990s to more than 242 400 protected areas covering 15% of the world’s land area (UN WCMC 2019). While there are a number of protected area categories, which vary from strict conservation areas (IUCN category I and II) to areas allowing sustainable resource extraction (category VI), biodiversity conservation is the primary objective of all IUCN protected areas (Dudley et al. 2008). Therefore, it is crucial to monitor the condition of protected areas to ensure they are free of the human pressures that compromise their ability to deliver long-term biodiversity conservation (Convention on Biological Diversity 2010). Previous global studies have revealed that many protected areas are facing substantial levels of human pressure within their boundaries, potentially reducing their ability to preserve the integrity of the ecosystems they contain (Rodrigues et al. 2004; Geldmann et al. 2013; Jones et al. 2018). For instance, Jones et al. (2018) revealed that about one-third of Earth’s protected land is under intense human pressure based on the global footprint framework developed by Venter et al. (2016). In a recent study, Anderson and Mammides (2019) showed intensification of human pressure inside protected areas within some of Earth’s remaining wilderness areas. However, these studies are global in scale and thus limited to the use of coarse, globally available data on human pressure. To provide decision makers with the information needed to make local-scale decisions about protected areas, refined human footprint maps and assessments of human pressure within protected areas are urgently required. There have been some studies conducted to evaluate human footprint at sub-national (Li et al. 2018) and ecoregional levels (Woolmer et al. 2008), but there is no study that focuses on national human footprint assessment and applies the findings to evaluate current protection status at multiple local scales (i.e., biomes, ecoregions, and provinces that shape a country).

Refined human footprint analyses are especially imperative in countries like Iran, home to over 100 vertebrate species including the Asiatic Cheetah (Acinonyx jubatus venaticus), the Persian Leopard (Panthera pardus), the Asiatic Black Bear (Ursus thibetanus), the Asiatic Wild Ass (Equus hemionus), and the Persian Fallow Dear (Dama Mesopotamia), all of which are classed as endangered or vulnerable by the IUCN Red List of Threatened Species (Karami et al. 2016). To protect this unique biodiversity, Iran has designated 284 protected areas including 31 national parks (IUCN category II), 38 National Natural Monuments (IUCN category III), 46 Wildlife Refuges (IUCN category IV), and 169 Protected Areas (IUCN Category VI), covering almost 11% of the country (17 800 000 ha) (Department of Environment 2019). Iran has committed to the objectives of Convention on Biological Diversity, and has developed a national strategic plan for biodiversity conservation (Department of Environment 2016). This plan states that Iran’s protected areas should safeguard iconic and endangered species, and their habitats, (e.g., the Asiatic Cheetah and the Persian leopard; Jowkar et al. 2016). However, there have been no assessments of the state of Iran’s protected areas, and thus it is unclear whether human impacts within protected areas may be compromising conservation of these species and their habitat.

In this study, we aimed to (1) develop the first contemporary national-scale human footprint map for Iran, and (2) examine the extent and intensity of human pressure within Iranian protected areas, to assess the effectiveness of conservation efforts at mitigating human impacts. Following the human footprint framework used by previous studies (Sanderson et al. 2002; Venter et al. 2016), we first develop a human footprint map for Iran using the highest resolution, most up-to-date geospatial data available on eight direct and indirect human pressure variables. These human pressures are (1) human population density; (2) extent of built environments; (3) crop lands; (4) pasture lands; (5) roads; (6) night-time lights; (7) railways; and (8) navigable waterways. Pressures were weighted according to their relative impact on the environment, following Venter et al. (2016), and then summed to create a standardized human footprint for Iran. Due to the importance of the methodology used in Venter et al. (2016) to generate a recent global footprint map, we highlight the similarities and differences of our national human footprint results with this global footprint map. To examine the applicability of this national human footprint map, we assessed the level of human pressure across Iran’s protected areas, and examined protection and human pressure levels across Iran’s biomes, ecoregions, and provinces. Our results highlight the need for objective assessments of how protected areas are faring in other countries with growing human pressure levels, and can also can inform conservation and land-use planning at national and regional scales in Iran.

Materials and Methods

Study area

Iran covers an area of 1 648 195 km² and is located in west Asia bordering the Caucasus Mountains and Caspian Sea in the north, and the Persian Gulf and Oman Sea in the south. This country is dominated by the Elburz Mountains in the north, and the Zagros Mountains along its western boundaries. The central and eastern parts of the country are mostly covered by the Plateau of Iran including several desert plains such as Dasht-e Kavir in the center, Dasht-e Lut desert in the south-east (Zehzad et al. 2002; Noroozi et al. 2008).

Iran comprises three different phytogeographic regions; the Hyrcanian and Nabo-sindian regions located in the north and south, respectively, with the rest of the country is occupied by Irano-turanian region (Zehzad et al. 2002). In the north of Iran, biomes such as temperate broadleaf and mixed forests are associated with the Hyrcanian region and temperate coniferous forests are associated with both Hyrcanian and Irano-turanian regions. Temperate broadleaf and mixed forests located in the west are mostly associated with the Irano-turanian region. Deserts and xeric shrublands, montane grasslands, and shrublands are mostly influenced by the Irano-turanian region in the center of the country and both Irano-turanian and Nabo-sindian regions in the south. There are temperate grasslands, savannas and shrublands, and flooded grasslands and savannas located in the west of Iran, mostly associated with the Irano-turanian region (UN WCMC 2017).

Iran provides a diverse range of habitats for animal species which mostly belong to the Palearctic region. The first attempts for protecting species and their habitats date back to 1967, when Iran’s first national park—Golestan—was established. Iran’s Department of Environment (DoE) was established in 1972 (Darvishsefat 2006), and the Environmental Protection and Rehabilitation Bill, approved in 1974, made the DoE officials responsible for protection of the entire country’s environment. One of the DoE’s crucial roles is to identify and protect areas with unique ecological characteristics and natural ecosystems, which provide habitat to valuable and endangered animal and plant species. A wide range of protected areas have been designated to do this, including national parks (IUCN category II), National Natural Monuments (IUCN category III), Wildlife Refuges (IUCN category IV), and Protected Areas (IUCN Category VI) (Fig. 1). In addition to IUCN classified protected areas, 13 Biosphere Reserves (under UNESCO Man and Biosphere program) and 25 Wetlands of International Importance (Ramsar Sites) have also been designated. However, Iran’s protected areas, and the unique biodiversity they hold, have been experiencing devastating threats, predominantly caused by human population growth, land conversion, improper management, and conflicts between local communities and protected areas (Makhdum 2008).

Fig. 1.

Iran’ protected areas, located in different terrestrial ecoregions

Human pressure data

The methodological steps undertaken to achieve the research objectives are shown in Fig. 2. In order to generate a national human footprint layer for Iran, we followed the method used by Venter et al. (2016). We considered eight human pressure variables, each of which was assigned a score between 0 and 10 (not all pressures could receive the maximum score of 10). The human pressures considered in our study were as follows: human population density, built environments, crop lands, pasture lands, roads, night-time lights, railways, and navigable waterways. We weighted these pressures according to their relative contributions to human pressures and summed them to generate the standardized human footprint for Iran. Because not all pressures can receive a maximum score of 10, the overall maximum possible human footprint score is 63. All spatial analyses were performed in ArcGIS 10.3 in Lambert projection at 100 m² resolution, so all data sources were resampled to 100 m² before analysis.

Fig. 2.

Methodological steps undertaken to address research objectives

Population density

For the human population density, we used population density data generated by the European Commission for the year 2015 (European Commission 2019b), which maps the number of people per 1 km² cell for the earth’s surface. This dataset uses the distribution and density of built-up areas to accurately map census data spatially (e.g., built-up areas have more population than remote areas). This is more accurate than the population density dataset used in Venter et al. (2016), which mapped census data to administrative units rather than built-up areas. For all locations with more than 1000 people per km², we assigned a pressure score of 10, and for more sparsely populated areas, we followed the methods of Venter et al. (2016) and logarithmically scaled the pressure score using the following equation in ArcGIS (Venter et al. 2016):

$$\text{Pressure score}=3.333\ast log(\text{population density}+1)$$

Built environments

To map built environments, we used data on global human settlements produced by the European Commission for the year 2015 (European Commission 2019a). These data classify human settlements by combining the degree of urbanization and population density at a 1 km² resolution. Following Venter et al. (2016), we assigned a pressure score of 10 to built areas using reclassify function in ArcGIS.

Crop lands

In order to map crop lands, we used global land cover data generated by the European Space Agency Climate Change Initiative (European Space Agency 2015). This dataset provides annual land cover maps from 1992 to 2015 at the resolution of 300 m, based on different satellite images taken by multiple satellites and their associated metadata, including Medium Resolution Imaging Spectrometer (MERIS) and Advanced Synthetic Aperture Radar (ASAR) archives, as two sensors of Environmental Satellite (EnviSat), and time series of Proba-V satellite. Following Venter et al. (2016) study, we assigned a score of 7 to all areas classified as crop lands in the study area.

Pasture lands

To map pasture areas, we used data from Gilbert et al. (2018), which maps density of cattle, sheep, goats, buffaloes, horses, chickens, and ducks at 5 arc-minute resolution (approx. 10 km² at the equator). After clipping the global layer to Iran’s boundary, we first aggregated all of these layers to generate a cumulative layer for pasture lands in ArcGIS. We then assigned a score of 4 to any cell above the 95th percentile of livestock density (345 000 animals per cell). For cells below this value, we logarithmically scaled the human pressure score down to zero using the rescaling function of the Spatial Analyst toolbox in ArcGIS.

Roads

To map roads, we used the 2017 Open Street Map database (Open Street Map 2017), extracting all road data except for private roads, tracks, and pedestrian paths because they are inconsistently mapped (Venter et al. 2016). In order to generate an accurate map of human pressure from roads at 100 m² resolution, we followed Woolmer et al. (2008) and applied pressure scores separately to different road classes. We first divided roads into four categories and then varied pressure scores based on distance intervals from different road categories (Table 1). Finally, we calculated an overall road pressure score for each cell by summing scores of roads for that cell.

Table 1.

Pressure scores for different types of roads adapted from (Woolmer et al. 2008)

Roads	0–100 m	100–500 m	500–1000 m	1000–3000 m
Motorways Trunk roads	10	8	6	4
Primary roads Secondary roads	8	6	4	2
Tertiary roads Residential roads	6	4	2	0
Service roads	4	2	1	0

Night-time lights, railways, and navigable waterways

In the absence of recent data on night-time lights, railways, and navigable waterways, we used the pressure layers generated in Venter et al. (2016) for the year 2009. Venter et al. (2016) used a global map of light sources generated using the U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) dataset (Elvidge et al. 2001), capable of detecting light sources from the earth’s surface including human settlements. This map was re-scaled on a 0–10 score to generate the night-time pressure map. To map railways, Venter et al. (2016) used data generated by the U.S. National Imagery and Mapping Agency (NIMA 1997) and assigned a pressure score of 8 for a distance of 0.5 km on either side of the railway. Navigable rivers, coasts, and inland seas layers were combined together to generate a general map for navigable water ways. Then, a score of 4 was assigned to the areas adjacent to the water bodies and then decreased exponentially out to 15 km.

Analyzing human footprint across protected areas, biomes, and ecoregions

In order to assess the current state of protected areas of Iran, we used our human footprint map to examine the level of human pressure within protected areas. We obtained data on protected area location, boundary, IUCN category and year of establishment from Iran’s DoE, and used ArcGIS to calculate mean human pressure levels within protected areas. We also calculated the proportion of protected areas under intense human pressure, defined as a human footprint score of equal to or greater than four (Watson et al. 2014; Jones et al. 2018). We also assessed the level of protection, and the extent and intensity of human pressure across Iran’s biomes and ecoregions. Biome and ecoregion data were taken from the Terrestrial Ecoregions of the World dataset (Olson et al. 2001). To explore how human pressures inside protected areas may compromise Iran’s progress towards global conservation targets, we also calculated biome and ecoregional protection levels when areas of intense human pressure within protected areas are removed from the protected area estate.

Results

Iran’s human footprint map ranges from 0 to 63, with a national mean score of 7.7. Areas of high human pressure are concentrated in the North and North-West of the country, where the major cities and agricultural activities occur (Fig. 3a). Human pressure is generally much lower in the East and South-East of the country, where it is more arid and less suitable for cropping. About 35% (58 million ha) of Iran’s area is under intense human pressure (defined here as a human footprint score ≥ 4), and these areas are again concentrated in the North and North-West. In contrast, only 1 200 000 ha (0.75%) of Iran has a human footprint score of zero, meaning no human pressures were mapped (Fig. 3a).

Fig. 3.

Maps showing a the current state of national human footprint in Iran, b mean HFP in protected areas, and c percent of land under intense pressure in each protected area

In order to compare the results of this study with previous global studies assessing human footprint, we visually compared our human footprint data to the human footprint map from the Venter et al. (2016) study. This comparison revealed a similar overall pattern of intense human footprint in the north and west of the country. However, the quantitative outputs revealed that our map shows lower average human footprint for Iran as a whole (7.7) and its protected areas (5.8), compared with the Venter et al. (2016) human footprint assessment, with the scores of 10.13 for Iran as a whole and 9.13 for its protected areas (Venter et al. 2016; Jones et al. 2018).

Assessing current state of protected areas in comparison with the latest human footprint data

On average, human pressure is lower inside Iran’s protected areas (mean score = 5.8) compared to unprotected land (mean score = 13.3). However, human activities are prevalent across many protected areas, and less than half of all protected areas are totally free from human pressure (Fig. 3b). Of Iran’s 17 500 000 ha protected area estate, 22% (3 850 000 ha) is under intense human pressure, with highly impacted protected areas mainly located in the North and West of the country (Fig. 3c). Around 7% of Iran’s protected areas have 100% of their extent under intense human pressure (HFP ≥ 4), and over 40% have half of their extent experiencing intense human pressure (Fig. 3c). Comparisons of individual human pressure maps and the distribution of protected areas show that the most widespread human pressures inside protected areas are roads, agriculture, and pasturelands.

The level of human pressure varies considerably across protected areas of different management categories. While protection level is theoretically highest in category II, we find that mean human pressure is fairly similar between category II and category VI protected areas, though a greater area is under intense pressure in category VI (Table 2). National parks (category II) have a mean human pressure score of 5.08, and 12.8% of their extent is under intense human pressure, whereas wildlife refuges (category IV) have a mean score of 7.38, with 12% of land under intense human pressure on average. Category VI protected areas have by far the most area under intense human pressure (28%; Table 2).

Table 2.

Mean human footprint score, and area under intense human pressure for protected areas

IUCN category	Area covered by IUCN category (ha)	Mean HFP	Standard deviation	Area under intense pressure (%)
31 National parks (category II)	1 982 560	5.08	5.05	12.8
46 Wildlife refuge (category IV)	5 730 625	7.38	9.05	12
169 Protected areas (category VI)	9 796 600	5.52	3.84	28

We also explored how these results differ when using other thresholds to define intense human pressure, and found that while the total area under intense human pressure changes considerably across different IUCN categories, category II and IV protected areas have similar human pressure levels, and category VI protected areas are more impacted (regardless of the thresholds used to define for intense human pressure) (Table S2).

Protection and human pressure across biomes and ecoregions

Across Iran’s biomes, the proportion of officially protected land ranges from 5% (Montane grasslands and shrublands) to 18.5% (flooded grasslands and savannas), but the level of human pressure in these protected areas varies considerably (Fig. 4). Flooded grasslands and savannas biomes have the largest proportion of their area protected, but more than half of the land protected within this biome (54%) is under intense human pressure (Fig. 4). Montane grasslands and shrublands have the lowest official protection levels (< 5%), but less than 15% of protected land is under intense human pressure (Fig. 4)

Fig. 4.

Proportion of biome areas identified as categories II, IV, VI with low (HFP < 4) and high human pressure (HFP ≥ 4) compared with the area unprotected

Of all biomes, temperate grasslands, savannas, and shrublands have the most impacted protected areas, with almost two-thirds of their protected land (400 000 ha) under intense human pressure (Fig. 4). Deserts and xeric shrublands have the most intact protected areas, with less than 1.4% (1 200 000 ha) under intense pressure. Overall, when area under intense human pressure is removed from the protected area estate, Deserts and Xeric Shrublands have the highest levels of protection (10.2%), despite having only the third-highest official protected area coverage (Fig. 4; Table S3).

At the ecoregional level, official protection varies from 0 to 18.5% (Figs. 5, 6). Tigris–Euphrates alluvial salt marshes have the highest protected area coverage (18.5%), but more than 60% of these protected lands (138 220 ha) are under intense human pressure (Fig. 5). The Zagros Mountains forest steppe have less than 1% of their total extent protected, and over 45% of these protected areas are under intense human pressure. In general, arid ecoregions have protected area estates with low human pressure, such as Central Persian Desert Basins (Fig. 5).

Fig. 5.

Maps representing different terrestrial ecoregions and protected areas under low (HFP < 4) and intense human pressure (HFP ≥ 4)

Fig. 6.

Proportion of ecoregion areas with protection under high human pressure compared with the total area protected. Solid line indicates those ecoregions with more than 17% of their areas protected based on convention of biodiversity target

Iran has only 2 ecoregions—Tigris–Euphrates alluvial salt marshes (18.5%) and Azerbaijan shrub desert and steppes (17.8%)- that are currently meeting the 17% protection level required under Aichi target 11 (part of Iran’s obligations under the Convention on Biological Diversity which states 17% of the country’s land should be protected by 2020); Convention on Biological Diversity 2010). These two ecoregions also have highly impacted protected areas, with areas under intense pressure comprising more than 82% of protected land in Azerbaijan shrub desert and 60% of protected land in Tigris–Euphrates alluvial salt marshes (Fig. 6). Both of these ecoregions would drop below the 17% protection target if land under intense human pressure was excluded from the protected area estate (Fig. 6). On average, progress towards Aichi target 11 would drop by 35% if land under intense human pressure was excluded (Fig. 6; Table S1).

Discussion

This is the first study that measures and maps human footprint at the national scale in Iran. Our findings indicate that almost the entire extent of the country (> 99%) is affected by at least one human pressure, and about 35% is subject to intense human pressure (HFP ≥ 4). Furthermore, many of Iran’s protected areas are facing high levels of human pressures, meaning they are failing to halt the human activities that drive biodiversity decline.

Although Iran is reported as being on track to meet global requirements for Aichi target 11 (UN WCMC 2017), our findings show that 22% of Iran’s protected land is under intense human pressure. This has considerable implications for Iran’s progress towards global conservation commitments. Iran’s current protected area estate covers around 10.78% of the country’s land, but if the area under intense human pressure was excluded from calculations, progress towards Aichi target 11 would drop from 10.78 to 8.50%. Furthermore, if protected areas under intense human pressure were excluded, none of Iran’s ecoregions would meet the 17% protection goal under Aichi target 11. Iran strives to meet its 2020 conservation commitments, and its 2030 national target to protect 20% of its land area (Department of Environment 2016). Our findings indicate that protected area expansion should be prioritized towards ecoregions with low protection levels, such as Azerbaijan shrub desert and steppe, Tigris–Euphrates alluvial salt marsh, Eastern Anatolian montane steppe, and Caspian Hyrcanian mixed forests. Iran’s conservation authorities could nominate the areas which are not officially protected in these ecoregions, such as no-hunting areas, forest reserves, national natural forests, and nature parks and list them as new protected areas. At the same time, there is also a need to more strictly manage protected areas, improve engagement with local communities to identify their demands, and implement recovery and restoration programs for degraded protected areas (Pringle 2017; Jones et al. 2018).

Our findings corroborate recent global studies which also show widespread human pressures within protected areas (Geldmann et al. 2014; Jones et al. 2018). These studies highlight the importance of considering biodiversity conservation performance when setting and measuring progress towards global targets, instead of relying on proxies such as area (Chauvenet and Barnes 2016). Although the proportion of protected lands across the world’s biogeographic regions has increased in the last few decades, recent studies argue that many parts of large and intact regions of terrestrial biomes are still substantially influenced by human activities (Watson et al. 2014; Anderson and Mammides 2019). Focusing only on protected area, expansion is unlikely to be sufficient to achieve conservation goals, especially if many protected areas are failing to stop the human activities which harm biodiversity. Consequently, we echo Tilman et al. (2017) in their call for the need to complement protected area expansion with other conservation actions (e.g., community/indigenous reserves), especially considering that protected areas often cause conflict with local communities (Watson et al. 2014). Incorporating local community’s opinions and preferences into policy and decision making, whether they are complementary or conflicting to conservation, may lead to more effective conservation actions in practice (Campbell et al. 2010; Karimi et al. 2017).

Examining those socioeconomic factors which contribute to intensifying human footprint within protected areas is a crucial future research direction (Rands et al. 2010; Sloan and Sayer 2015). Many countries are experiencing large increases in human pressures, poor infrastructure, and inadequate management budgets in their protected areas (Tilman et al. 2017) and Iran is not an exception. As such, a better understanding of when and how these human activities are most likely to impact protected areas will allow conservationists to design strategies to combat them. This will require nations to move beyond reporting only on the extent of protected areas, and conduct robust assessments of the effectiveness of their protected areas at halting the human activities which harm biodiversity, as we have done here for Iran.

When doing so, it is important that nations recognize the accuracy limitations of global human pressure datasets (Woolmer et al. 2008). We found large differences between our Iran-specific human footprint map, and the global human footprint map from Venter et al. (2016), so we urge other countries to consider generating country-specific maps on which to make conservation decisions. Global human footprint maps, which measure change over time, are limited to using data that are collected consistently over time and hence, they cannot use the most up-to-date or high-resolution data. In this study, we were not limited to using input data that measure change over time and this enabled us to map human pressure at a spatial resolution ten times greater than previous studies. To be able to further examine the differences between national-scale human footprints and existing global results, future studies could try to select the same databases as used in global studies for developing their national footprint maps, while ensuring that appropriate resolutions are applied. This can reveal the possible trade-offs researchers should consider between improving accuracy and spatial resolution of human footprint maps and being able to statistically compare the national-scale human footprint with the global results.

One reason for widespread human pressure within Iran’s protected areas is that a lack of land-use planning has resulted in the allocation of various land-uses with no consideration of the conflicting nature of uses (e.g., agriculture, grazing or industrial development occurring on the boundary of or inside protected areas). This is the case for many countries worldwide (Jones et al. 2018). Given the widespread and numerous conflicts between human development activities (e.g., agriculture) and conservation activities (e.g., protected areas), it is clear that effective conservation will require national conservation agencies to undertake land-use planning analyses to address trade-offs between conservation and development. Better allocating land-uses at local scales will improve overall biodiversity conservation at a landscape scale. The identification of public interests and potential conflicts can support planners to select effective strategies to reconcile conservation and other types of land-uses (Campbell et al. 2010; Sayer et al. 2013).

The findings of this study provide valuable information to conservation authorities concerned with whether proposed national policies are effectively being implemented to meet global and national targets. Iran has released national biodiversity strategies and action plans for biodiversity for the period of 2016–2030, which is aligned with the CBD’s Strategic Plan for Biodiversity 2011–2020 and Target 17 of the Aichi Biodiversity Targets. The goal of this agenda is to increase the participation of both the Iranian government and society in biodiversity conservation and restoration, by raising public awareness on the importance of biodiversity for human well-being, and improving the conservation status of Iran’s species, habitats, and genetic resources (Department of Environment 2016). With more than half of all protected lands under the influence of human activities (HFP ≥ 1), we urge authorities to review current policies and ensure that action plans are relevant to the current conditions of protected areas.

Our results highlight one of the long-term threats facing Iran’s protected areas and their biodiversity. Because herding has been practiced in Iran since the 11th century (Amanat 2016), grazing on the remaining native pastures still occurs based on herders’ historical right of access. This grazing reduces the ecological capacity of pastures to produce forage, and also prevents effective regeneration/restoration from occurring. A lack of effective control on livestock overgrazing in protected areas and their surroundings has led to increase in human-induced mortality rates of iconic species such as Asiatic Cheetahs (Farhadinia et al. 2017). Iran’s government recognized this overgrazing problem in a 2016 revision of its conservation strategies and actions plans, but the report lacks practical guidance on which actions should be implemented to combat it. For instance, the report suggests the revising management plans in areas facing overuse and overexploitation of natural resources (Department of Environment 2016). However, it is unclear how this could be implemented on the ground. Our findings can augment the country’s national conservation strategies and actions by providing authorities with information on the spatial distribution and intensity of human pressures (e.g., overgrazing) in protected areas. A valuable next step will be to define effective policies to control grazing patterns and intensity, which should be informed by rigorous studies that determine real carrying capacity of native pastures, including those inside protected areas.

The findings of this study also highlight the profound challenges Iran’s government faces in terms of appropriately funding and equipping protected areas to support the necessary conservation actions within protected areas (Watson et al. 2014). The protected area management system in Iran lacks comprehensive studies to quantify the return on investment that well-managed protected areas provide, through the provision of natural resources to local people, increased economic benefits resulting from tourism activities, and safeguarding the capacity of natural ecosystems to provide essential services [e.g., clean water, climate regulation, flood, and soil erosion control (Balmford et al. 2002)]. Systemic underfunding of protected areas has also resulted in a lack of information regarding how well a given protected area is being managed. All of these challenges mean government authorities are unable to assess how effective their current management strategies are at halting national biodiversity loss. Therefore, conducting periodic comprehensive assessments of the benefits that protected areas provide may help justify local conservation decisions. Further, implementing incentives through tax reduction or payments for ecosystem services may help reduce conflicts between conservation and local communities (Campbell et al. 2010). Reviewing existing IUCN management categories and designating flexible management categories (e.g., VI) as buffers around stricter categories (II), where possible, can also help reduce conflicts as local people are allowed to sustainably use natural resources of these buffer areas.

While we developed the most up-to-date map of human pressure for Iran, our work is subject to some limitations. First, while we assumed those areas under intense human pressure do not contribute towards conservation targets, they may still contain some elements of biodiversity (Jones et al. 2018). Second, we were not able to consider all human pressures on the environment, as we were unable to consider illegal hunting, climate change, or invasive species (Venter et al. 2016). Third, by mapping human footprint, we measured the pressures human activities place on nature, not the realized states or impacts on natural systems or their biodiversity. Fourth, while the findings of this study enable conservation authorities to assess the current status of protected areas, they do not allow for comparisons through time. Assessing the effectiveness of protected areas in reducing human pressures on biodiversity through multiple time periods using geospatial data from similar data sources would be a valuable future research direction. To further examine the effects of human pressures on protected areas, future studies could compare the extent to which different animal species and plant communities are affected within protected areas.

Conclusion

With increasing human population growth, threats to biodiversity will continue to grow into the future. The maintenance of biodiversity and ecosystem function in the face of these threats will depend on the success of actions taken by countries to meet their global conservation commitments (e.g., to the Convention on Biological Conservation).

While Iran is on track to meet its 2020 protected area commitments under the CBD, our results show that human pressure occurring inside protected areas may be compromising their ability to deliver conservation outcomes. We found that about 35% of Iran’s terrestrial area, and about 22% of its legally protected lands are facing intense human pressure. There is thus a clear need to not only expand the protected area estate, but also to improve protected area management to prevent or remove the threats that impact biodiversity. The findings of this study can inform Iran’s national conservation policies and actions (e.g., the National Biodiversity Strategy and Action Plan), and highlight the need for Iran’s conservation agencies to (1) implement an effective land-use plan aimed at reducing the conflicts between protected areas and other land-uses (e.g., agriculture, grazing), (2) negotiate with local communities and accommodate their needs through relevant policies, and (3) allocate protected areas resources based on the extent and the intensity of human pressures affecting them. By developing a national-scale human footprint map based on the methodology proposed by previous studies, we also demonstrate a repeatable high-resolution approach which can be applied to assess human pressure across individual nations and their protected areas worldwide.

Electronic supplementary material

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Biographies

Azadeh Karimi

is the corresponding author of this paper. She is an Assistant Professor at the Ferdowsi University of Mashhad, Iran. Her research interests include spatial prioritization, landscape planning, conservation planning and public participation.

Kendall Jones

is a Spatial Planning Specialist at Wildlife Conservation Society. His research interests include spatial prioritization, Conservation Biology and Climate change.