Human Appropriation of Net Primary Production (HANPP)

Figure 1. Development of HANPP and HANPP per capita from 1910 to 2005 in five world regions (from Krausmann et al., 2013).

A recent estimate has quantified global HANPP at 15 GtC per year in 2005, which means that humanity appropriated roughly 25% of the potential NPP in that year, following a robust, but not over-encompassing definition by Haberl et al. (2007, see Haberl et al., 2014). In the last century HANPP has roughly doubled, driven by the growing demand for biomass and the expansion of agriculture. It has, however, been growing in all world regions at a slower rate than population, and all regions experienced a declining significance of land use-induced productivity losses (HANPPluc) and a growing share of harvested NPP in HANPP. Otherwise, the specific patterns of HANPP differ substantially. Asia, Africa, and Latin America experienced very high growth rates in HANPP; as a percentage of NPPpot, HANPP doubled or even tripled in these regions during the last century. With the expansion of agriculture, these regions caught up with or even surpassed the initially high HANPP percentage levels in the Western Industrialized region and the former Soviet Union and Eastern Europe (FSU-EE). In contrast, in the Western Industrialized region, HANPP grew only modestly. It rose from 18% to 23% of NPPpot in the 1980s and has stabilized since then. The development of HANPP in FSU-EE mostly tracked that in the Western Industrial region until 1990, but after the collapse of the Communist system and the disintegration of its agricultural production system, HANPP rapidly declined from 22% to 16% of NPPpot. HANPP as a percentage of NPPpot has converged globally and falls into a relatively narrow range in all regions except Asia (ranging from 16% to 23% in 2005), but per capita HANPP varies greatly. HANPP per capita reflects three key factors: one, the amount and mix of biomass products consumed per capita, which generally increases with income and consumption of more HANPP-intensive products such as meat and milk; two, the efficiency of biomass production relative to NPPpot; and three, net biomass imports or exports.

Evidence is increasing that suggests that decreases in the energy availability in ecosystems, as measured by HANPP, negatively affect biodiversity. The availability of trophic energy is a key ecological parameter determining observed patterns of biodiversity, especially at large scales. The species-energy hypothesis suggests that energy availability in an ecosystem is positively related to species diversity. Indeed, a meta-analysis found a positive relationship between ecological productivity and species richness. A reduction of trophic energy availability in ecosystems resulting from growing HANPP is likely to affect crucial aspects of biodiversity, such as species richness, abundance and composition.

Indicator relationship to Aichi Targets:

Target 4: By 2020, at the latest, Governments, business and stakeholders at all levels have taken steps to achieve or have implemented plans for sustainable production and consumption and have kept the impacts of use of natural resources well within safe ecological limits.

Use of natural resources in terms of biomass is directly linked to and can be quantified by HANPP. A major achievement of the HANPP framework is that it integrates consistently land-use implications due to land cover changes as well as due to land-use intensity changes. In particular the latter is currently under-researched and lacks robust, encompassing indicators, despite the large body of evidence that suggests a strong impact of land-use intensification on biodiversity.

Target 7: By 2020 areas under agriculture, aquaculture and forestry are managed sustainably, ensuring conservation of biodiversity.

Sustainable use of agricultural and forestry areas can be indicated by changes in HANPP.

Target 8: By 2020, pollution, including from excess nutrients, has been brought to levels that are not detrimental to ecosystem function and biodiversity.

Changes in land productivity and land use intensity resulting from fertilizer reduction can be detected by HANPP.

Target 12: By 2020 the extinction of known threatened species has been prevented and their conservation status, particularly of those most in decline, has been improved and sustained.

Pressure changes on habitats of known threatened species can be linked to HANPP.

Target 15: By 2020, ecosystem resilience and the contribution of biodiversity to carbon stocks has been enhanced, through conservation and restoration, including restoration of at least 15 per cent of degraded ecosystems, thereby contributing to climate change mitigation and adaptation and to combating desertification.

HANPP is able to measure changes in biomass flows that are directly linked to carbon stocks via the turn over.

Coverage: Global, Sub-global, Regional, National. Global national (data are available for ca. 150 countries and can aggregated to different world regions and country groupings (e.g. UNEPlive regions) (see Krausmann et al. 2013); Global 2000 (5 arc. min) (see Haberl et al. 2007) Long term national scale studies for a growing number of countries (see Gingrich et al. 2015) Europe (1990, 2000, 2006): 1km Scale (see Plutzar et al. 2015).

Scale: HANPP data are available at different scales from global to national and regional and also as spatially explicit maps (see above).

Time series available: A global database exists which provides HANPP data for 1960, 1970, 1980, 1990, 2000 and 2005. National long term time series provide information on HANPP development during the last one or two centuries.

Next planned update: An update of the global spatially explicit HANPP map is planned for 2019.

Methodology: HANPP is the sum of productivity changes resulting from land conversion and land use (HANPPluc) and harvest (HANPPharv). From an ecological perspective it is the difference between potential (NPPpot) and current (NPPeco) NPP, where NPPeco is the NPP of the actual vegetation (NPPact) minus HANPPharv. Whereas some studies focus on estimating HANPPluc based on land-use data, others use these data together with remotely sensed information to directly estimate NPPact and calculate HANPPluc by subtracting NPPact from NPPpot. In both cases, an estimate of NPPpot is required that can be derived by vegetation models of varying complexity: Empirical models use correlations between climate and measured productivity at individual sites, using data sets collected during the International Biological Program. Dynamic vegetation models are stock-flow models that simulate a plethora of ecological processes, including the exchanges between plants and atmosphere such as GPP and plant respiration, using spatially explicit climate data. HANPPharv is derived from agricultural and forestry statistics combined with material and energy flow methods, land-use data, and simple models based on a large array of statistical data combined with basic physiological knowledge and thermodynamic considerations to close data gaps. Different approaches are used to estimate NPPact. NPPact on cropland can be extrapolated from data on crop harvest, using appropriate coefficients for the share of crop harvest in aboveground biomass (harvest indices) and ratios of aboveground to belowground biomass. NPP on forestland and grassland is usually derived with a vegetation model taking information on soil degradation and irrigation into account. Deriving land-use data sets suitable for robust HANPP calculations involves substantial efforts because a closed-budget approach is required to be able to consistently combine data from remote sensing, vegetation modelling, and statistical data sets in spatially explicit (geographic information systems, or GIS) databases. Closed budget means that for each pixel, the sum of land-use classes (e.g., infrastructure, cropland, forestry, grazing, and wilderness) must total 100% and that national totals can be related to national totals of the respective land-use classes as reported in agriculture and forestry statistics. See Haberl et al. 2014 for details.

Figure 2. Definition of HANPP and different HANPP parameters. Source: Haberl et al. 2014

Producing this indicator nationally: A rough estimate of HANPP for a national economy based on data on land use and biomass harvest, using standard procedures can be compiled in a few weeks, given that detailed high quality data are available. Spatially explicit HANPP maps are more difficult to establish and require resources for research.

Use of the global method and data at the national level: A global HANPP database contains national HANPP data for selected years between 1960 to 2005. The indicator methodology can be applied with in-country data to develop a national indicator. This requires comprehensive data on land use and agriculture and forestry harvest and access to NPP data from a global vegetation model or data on temperature and precipitation to estimate NPPpot.

Examples of national use:

• South Africa
• Spain
• Phillipines
• Europe
• Germany
• Italy
• Czech Republic
• Africa
• New Zealand
• Canada

Publications and reports

Erb et al 2009 - Embodied HANPP: Mapping the Spatial Disconnect between Global Biomass Production and Consumption

Haberl et al 2007 - Quantifying and Mapping the Human Appropriation of Net Primary Production in Earth’s Terrestrial Ecosystems

Haberl et al 2014 - Human Appropriation of Net Primary Production: Patterns, Trends, and Planetary Boundaries

Haberl et al - Changes in Ecosystem Processes Induced by Land Use: Human Appropriation of Aboveground NPP and Its Influence on Standing Crop in Austria

Haberl et al 2012 - Global Effects of National Biomass Production and Consumption: Austria’s Embodied HANPP Related to Agricultural Biomass in the Year 2000

Haberl et al 2005 - Human Appropriation of Net Primary Production as Determinant of Avifauna Diversity in Austria

Haberl et al 2004 - Human Appropriation of Net Primary Production and Species Diversity in Agricultural Landscapes

Krausmann et al 2013 - Global Human Appropriation of Net Primary Production Doubled in the 20th Century

Krausmann et al 2009 - What Determines Geographical Patterns of the Global Human Appropriation of Net Primary Production

Plutzar et al 2016 - Changes in the Spatial Patterns of Human Appropriation of Net Primary Production (HANPP) in Europe 1990–2006

Vitousek et al 1986 - Human Appropriation of the Products of Photosynthesis

Krausmann et al., 2012. Long-term trajectories of the human appropriation of net primary production: Lessons from six national case studies

Daly 1992 - From empty-world to full-world economics: Recognizing an historical turning point in economic development