Linking land use inventories to biodiversity impact assessment methods

The International Journal of Life Cycle Assessment - There is generally a mismatch in the land use classification of life cycle inventory (LCI) databases and life cycle impact assessment (LCIA)...     

UNEP-SETAC guideline on global land use impact assessment on biodiversity and ecosystem services in LCA

Purpose

As a consequence of the multi-functionality of land, the impact assessment of land use in Life Cycle Impact Assessment requires the modelling of several impact pathways covering biodiversity and ecosystem services. To provide consistency amongst these separate impact pathways, general principles for their modelling are provided in this paper. These are refinements to the principles that have already been proposed in publications by the UNEP-SETAC Life Cycle Initiative. In particular, this paper addresses the calculation of land use interventions and land use impacts, the issue of impact reversibility, the spatial and temporal distribution of such impacts and the assessment of absolute or relative ecosystem quality changes. Based on this, we propose a guideline to build methods for land use impact assessment in Life Cycle Assessment (LCA).

Results

Recommendations are given for the development of new characterization models and for which a series of key elements should explicitly be stated, such as the modelled land use impact pathways, the land use/cover typology covered, the level of biogeographical differentiation used for the characterization factors, the reference land use situation used and if relative or absolute quality changes are used to calculate land use impacts. Moreover, for an application of the characterisation factors (CFs) in an LCA study, data collection should be transparent with respect to the data input required from the land use inventory and the regeneration times. Indications on how generic CFs can be used for the background system as well as how spatial-based CFs can be calculated for the foreground system in a specific LCA study and how land use change is to be allocated should be detailed. Finally, it becomes necessary to justify the modelling period for which land use impacts of land transformation and occupation are calculated and how uncertainty is accounted for.

Discussion

The presented guideline is based on a number of assumptions: Discrete land use types are sufficient for an assessment of land use impacts; ecosystem quality remains constant over time of occupation; time and area of occupation are substitutable; transformation time is negligible; regeneration is linear and independent from land use history and landscape configuration; biodiversity and multiple ecosystem services are independent; the ecological impact is linearly increasing with the intervention; and there is no interaction between land use and other drivers such as climate change. These assumptions might influence the results of land use Life Cycle Impact Assessment and need to be critically reflected.

Conclusions and recommendations

In this and the other papers of the special issue, we presented the principles and recommendations for the calculation of land use impacts on biodiversity and ecosystem services on a global scale. In the framework of LCA, they are mainly used for the assessment of land use impacts in the background system. The main areas for further development are the link to regional ecological models running in the foreground system, relative weighting of the ecosystem services midpoints and indirect land use.     

The impact of land use and land cover change on biodiversity within and adjacent to Kibasira Swamp in Kilombero Valley,Tanzania

Wetlands are crucial ecosystems with multiple values and functions to a range of different stakeholders. The future of wetlands depends both on the legacy of the past and how they are currently used. Using 48 vegetation survey plots (0.08 ha) combined with Landsat 5 and 7 TM imagery, we assessed the influence of long‐term (1990–2011) land use and land cover change on the biodiversity of the Kibasira Swamp. Information on perceptions of adjacent communities on historical changes and drivers for the changes were also collected. Results showed an increase in the area covered by open water by 1% and forest by 4% between 1990 and 1998 whilst Cyperus papyrus L and cultivated land area decreased by 8% and 3%, respectively on the same period. Between 1998 and 2011, there was a decrease in areas covered by water by 35% and forest by 9% whereas C. papyrus L increased by 40% and cultivated land increased by 8%. These changes have affected the biodiversity of the swamp and adjacent to it as numbers of mammals have declined. However, the Swamp still provides extensive habitat for plants and bird species despite the ongoing human pressure. Interventions may be necessary to maintain biodiversity in Kibasira Swamp to ensure sustainable ecosystem services.     

Reviewing the potential for including habitat fragmentation to improve life cycle impact assessments for land use impacts on biodiversity

Purpose

The biosphere is progressively subjected to a variety of pressures resulting from anthropogenic activities. Habitat conversion, resulting from anthropogenic land use, is considered the dominant factor driving terrestrial biodiversity loss. Hence, adequate modelling of land use impacts on biodiversity in decision-support tools, like life cycle assessment (LCA), is a priority. State-of-the-art life cycle impact assessment (LCIA) characterisation models for land use impacts on biodiversity translate natural habitat transformation and occupation into biodiversity impacts. However, the currently available models predominantly focus on total habitat loss and ignore the spatial configuration of the landscape. That is, habitat fragmentation effects are ignored in current LCIAs with the exception of one recently developed method.

Methods

Here, we review how habitat fragmentation may affect biodiversity. In addition, we investigate how land use impacts on biodiversity are currently modelled in LCIA and how missing fragmentation impacts can influence the LCIA model results. Finally, we discuss fragmentation literature to evaluate possible methods to include habitat fragmentation into advanced characterisation models.

Results and discussion

We found support in available ecological literature for the notion that habitat fragmentation is a relevant factor when assessing biodiversity loss. Moreover, there are models that capture fragmentation effects on biodiversity that have the potential to be incorporated into current LCIA characterisation models.

Conclusions and recommendations

To enhance the credibility of LCA biodiversity assessments, we suggest that available fragmentation models are adapted, expanded and subsequently incorporated into advanced LCIA characterisation models and promote further efforts to capture the remaining fragmentation effects in LCIA characterisation models.

     

Coupling GIS and LCA for biodiversity assessments of land use

Purpose  

Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California.     

Coupling GIS and LCA for biodiversity assessments of land use

Purpose  

Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California.     

The impact of land conversion on plant biodiversity in the forest zone of Cameroon

Floristic surveys were carried out in different land use systems(primary and secondary forest, fallows of different ages, cocoa plantations,crop fields) within the forest zone of Cameroon, to assess the impact of landconversion on above-ground plant biodiversity. Beside various diversity studies,plant density was measured and diameter at breast height was estimated.The results showed that the forest areas, which represent thehistoric biodiversity of the region, preserve the greatest number of species(160 species in primary forest and 171 in secondary forest). Our resultsindicate the relatively great importance of secondary forests as refuge areasfor primary forest plant species that may function as a starting point forpossible regeneration of original biodiversity. Species richness is reducedprogressively from the original forest (160 spp.) and secondary forests (171spp.), to Chromolaena odorata (Asteraceae) fallow fields(149 spp.), to an old fallow field (139 spp.), to a cocoa plantation (116 spp.)and to the farmland (64 spp.), where only weeds and crops contribute essentiallyto plant biodiversity. Also the number of species that are used for non-timberproducts (construction, food and medicines) decreased with increased landconversion.     

Assessment of land use impacts on the natural environment

Goal, Scope and Background  

Land use is an economic activity that generates large benefits for human society. One side effect, however, is that it has caused many environmental problems throughout history and still does today. Biodiversity, in particular, has been negatively influenced by intensive agriculture, forestry and the increase in urban areas and infrastructure. Integrated assessment such as Life Cycle Assessment (LCA), thus, incorporate impacts on biodiversity. The main objective of this paper is to develop generic characterization factors for land use types using empirical information on species diversity from Central Europe, which can be used in the assessment method developed in the first part of this series of paper.     

Scale‐dependent impact of land management on above‐ and belowground biodiversity

1. Land management is known to have consequences for biodiversity; however, our synthetic understanding of its effects is limited due to highly variable results across studies, which vary in the focal taxa and spatial grain considered, as well as the response variables reported. Such synthetic knowledge is necessary for management of agroecosystems for high diversity and function.
2. To fill this knowledge gap, we investigated the importance of scale‐dependent effects of land management (LM) (pastures vs. meadows), on plant and soil microbe diversity (fungi and bacteria) across 5 study sites in Central Germany. Analyses included diversity partitioning of species richness and related biodiversity components (i.e., density of individuals, species‐abundance distribution, and spatial aggregation) at two spatial grains (α‐ and γ‐scale, 1 m² and 16 km², respectively).
3. Our results show scale‐dependent patterns in response to LM to be the norm rather than the exception and highlight the importance of measuring species richness and its underlying components at multiple spatial grains.
4. Our outcomes provide new insight to the complexity of scale‐dependent responses within and across taxonomic groups. They suggest that, despite close associations between taxa, LM responses are not easily extrapolated across multiple spatial grains and taxa. Responses of biodiversity to LM are often driven by changes to evenness and spatial aggregation, rather than by changes in individual density. High‐site specificity of LM effects might be due to a variety of context‐specific factors, such as historic land management, identity of grazers, and grazing regime.
5. Synthesis and applications: Our results suggest that links between taxa are not necessarily strong enough to allow for generalization of biodiversity patterns. These findings highlight the importance of considering multiple taxa and spatial grains when investigating LM responses, while promoting management practices that do the same and are tailored to local and regional conditions.

     

The origins of modern biodiversity on land

Comparative studies of large phylogenies of living and extinct groups have shown that most biodiversity arises from a small number of highly species-rich clades. To understand biodiversity, it is important to examine the history of these clades on geological time scales. This is part of a distinct 'phylogenetic expansion' view of macroevolution, and contrasts with the alternative, non-phylogenetic 'equilibrium' approach to the history of biodiversity. The latter viewpoint focuses on density-dependent models in which all life is described by a single global-scale model, and a case is made here that this approach may be less successful at representing the shape of the evolution of life than the phylogenetic expansion approach. The terrestrial fossil record is patchy, but is adequate for coarse-scale studies of groups such as vertebrates that possess fossilizable hard parts. New methods in phylogenetic analysis, morphometrics and the study of exceptional biotas allow new approaches. Models for diversity regulation through time range from the entirely biotic to the entirely physical, with many intermediates. Tetrapod diversity has risen as a result of the expansion of ecospace, rather than niche subdivision or regional-scale endemicity resulting from continental break-up. Tetrapod communities on land have been remarkably stable and have changed only when there was a revolution in floras (such as the demise of the Carboniferous coal forests, or the Cretaceous radiation of angiosperms) or following particularly severe mass extinction events, such as that at the end of the Permian.     

Land use and biodiversity indicators for life cycle impact assessment

Background  The primary purpose of environmental assessment is to protect biological systems. Data collected over the last several decades indicates that the greatest impacts on biological resources derive from physical changes in land use. However, to date there is no consensus on indicators of land use that could be applicable worldwide at all scales. This has hampered the assessment of land use in the context of LCA. Objectives  The Institute for Environmental Research and Education and its partner Defenders of Wildlife have begun an effort to develop the necessary consensus. Methods  In July 2000, they held a workshop attended by a diverse group of interested parties and experts to develop a preliminary list of life cycle indicators for land use impacts. Results  Their preliminary list of impact indicators includes: protection of priority habitats/species; soil characteristics: soil health; proximity to & protection of high priority vegetative communities; interface between water and terrestrial habitats/buffer zones; assimilative capacity of water and land; hydrological function; percent coverage of invasive species within protected areas; road density; percent native-dominated vegetation; restoration of native vegetation; adoption of Best Management Practices linked to biodiversity objectives; distribution (patchiness; evenness, etc.); and connectivity of native habitat. Conclusion  The list of indicators conforms well to other efforts in developing indicators. There appears to be convergence among experts in the field and in related fields on the appropriate things to measure. Future Prospects  These indicators are currently being tested in the United States. Further workshops and testing is planned towards developing internationally recognized indicators for land use.     

Assessing conservation values: biodiversity and endemicity in tropical land use systems

Despite an increasing amount of data on the effects of tropical land use on continental forest fauna and flora, it is debatable whether the choice of the indicator variables allows for a proper evaluation of the role of modified habitats in mitigating the global biodiversity crisis. While many single-taxon studies have highlighted that species with narrow geographic ranges especially suffer from habitat modification, there is no multi-taxa study available which consistently focuses on geographic range composition of the studied indicator groups. We compiled geographic range data for 180 bird, 119 butterfly, 204 tree and 219 understorey plant species sampled along a gradient of habitat modification ranging from near-primary forest through young secondary forest and agroforestry systems to annual crops in the southwestern lowlands of Cameroon. We found very similar patterns of declining species richness with increasing habitat modification between taxon-specific groups of similar geographic range categories. At the 8 km(2) spatial level, estimated richness of endemic species declined in all groups by 21% (birds) to 91% (trees) from forests to annual crops, while estimated richness of widespread species increased by +101% (trees) to +275% (understorey plants), or remained stable (-2%, butterflies). Even traditional agroforestry systems lost estimated endemic species richness by -18% (birds) to -90% (understorey plants). Endemic species richness of one taxon explained between 37% and 57% of others (positive correlations) and taxon-specific richness in widespread species explained up to 76% of variation in richness of endemic species (negative correlations). The key implication of this study is that the range size aspect is fundamental in assessments of conservation value via species inventory data from modified habitats. The study also suggests that even ecologically friendly agricultural matrices may be of much lower value for tropical conservation than indicated by mere biodiversity value.     

土地利用变化对土壤真菌群落结构的影响

应用PCR-RFLP和测序分析对川西亚高山米亚罗林区不同土地利用类型的土壤真菌18S rDNA基因进行了多样性和系统发育研究,探讨了土地利用变化对土壤真菌群落结构的影响。在20a龄云杉(Picea likiandensis var balfourianan)人工林和菜地两种类型土壤中,共得到238个阳性克隆,限制性内切酶MspI和RsaI进行RFLP分析后得到56个不同的分类操作单元(OTUs),其中20a龄云杉人工林样地获得137个阳性克隆和37个OTUs,而菜地样地获得101个阳性克隆和19个OTUs。在两类样地中具有不同的优势种群,其中20a龄云杉人工林样地有1个明显优势种群,占总克隆数的20.4%;菜地样地有2个明显优势种群,分别占总克隆数的25.7%和21.8%。对14个克隆进行了序列测定,序列的相似性在86%~99%之间,与GenBank数据库中的序列进行比对,与已知序列的相似性在92%~100%之间。系统发育分析表明,所有的18SrDNA基因被分为3个主要的簇,其中20a龄云杉人工林样地的克隆都聚集在第一和第三簇中,而菜地样地的克隆都聚集在第二簇中。结果说明,两类土壤中具有较为丰富的真菌多样性,而土地利用变化引起了土壤真菌群落结构的明显变化。     

Impact of land use changes on water resources and biodiversity of Lake Nakuru catchment basin, Kenya

Lake Nakuru, Kenya, is one of a series of saline–alkaline closed basin lakes in the eastern arm of the Rift Valley. The lake has been variously described as ' the lake of a million flamingos' and 'the Worlds greatest ornithological spectacle' and is bedrock to the areas' tourism. The lake was designated a bird sanctuary in 1960, a National Park in 1968, first rhino sanctuary in 1987, first Kenyan Ramsar site in 1990, an Important Bird Area in 1999 and a world-class national park in 2005. Over the last 40 years, its basin has been heavily settled, extensively cultivated, urbanized and industrialized. Environmental problems include poor agricultural practices, human encroachment, pollution, wildlife mortality/morbidity, human/wildlife conflicts, poverty, ethnic tensions and land clashes and lack of adequate legal and policy framework. Approaches to conservation have been initiated against identified existing problems and constraints. These approaches are (i) organizational and institutional development; (ii) hot spots and pollution loads management and (iii) catchment and park management. Constraints have been identified as unclear demarcation of responsibilities, lack of budget, skilled staff and know-how and lack of environmental standards and regulations. The impacts of ecosystem changes on people's lives and livelihoods are discussed.     

The impact of beech thickets on biodiversity

Beech bark disease has dramatically altered hardwood forest structure and composition across northeastern North America. Extensive overstory mortality has resulted in prolific root-sprouting in some stands leading to the development of understory thickets of clonal small-stemmed beech. Beech thickets may impact local forest biodiversity, but this has not been adequately evaluated. We hypothesized significant differences in diversity of groundcover flora, craneflies, amphibians, and small mammals between plots with and without beech thickets. Paired plots were established in uneven-aged northern hardwood forest stands with no recent management history at two sites in the Adirondack Mountains of New York State. Groundcover plants, terrestrial craneflies, amphibians and small mammals were sampled on twenty paired plots. Discriminant analysis showed a significant difference between thicket and non-thicket (control) areas; significant variables in plot type separation were beech sapling abundance, leaf litter depth, and coarse woody debris volume. Groundcover plant cover, richness, and diversity were significantly lower in thicket compared to non-thicket plots, while beech sapling density explained 17–38 % in groundcover plant species diversity. There were no significant differences between the diversity of cranefly, amphibian and small mammal communities of each plot type. Beech thickets are important determinants of local biodiversity.