The rising popularity of biodiversity offsetting as a tool for balancing biodiversity losses from development with equivalent gains elsewhere has sparked debate on many fronts. The fundamental questions are the following: is offsetting good, bad, or at least better than the status quo for biodiversity conservation outcomes, and what do we need to know to decide?We present a concise synthesis of the most contentious issues related to biodiversity offsetting, categorized as ethical, social, technical, or governance challenges. In each case, we discuss avenues for reducing disagreement over these issues and identify those that are likely to remain unresolved. We argue that there are many risks associated with the unscrutinized expansion of offset policy. Nevertheless, governments are increasingly adopting offset policies, so working rapidly to clarify and-where possible-to resolve these issues is essential.

Climate change is having a significant impact on ecosystem services and is likely to become increasingly important as this phenomenon intensifies. Future impacts can be difficult to assess as they often involve long timescales, dynamic systems with high uncertainties, and are typically confounded by other drivers of change. Despite a growing literature on climate change impacts on ecosystem services, no quantitative syntheses exist. Hence, we lack an overarching understanding of the impacts of climate change, how they are being assessed, and the extent to which other drivers, uncertainties, and decision making are incorporated. To address this, we systematically reviewed the peer-reviewed literature that assesses climate change impacts on ecosystem services at subglobal scales. We found that the impact of climate change on most types of services was predominantly negative (59% negative, 24% mixed, 4% neutral, 13% positive), but varied across services, drivers, and assessment methods. Although uncertainty was usually incorporated, there were substantial gaps in the sources of uncertainty included, along with the methods used to incorporate them. We found that relatively few studies integrated decision making, and even fewer studies aimed to identify solutions that were robust to uncertainty. For management or policy to ensure the delivery of ecosystem services, integrated approaches that incorporate multiple drivers of change and account for multiple sources of uncertainty are needed. This is undoubtedly a challenging task, but ignoring these complexities can result in misleading assessments of the impacts of climate change, suboptimal management outcomes, and the inefficient allocation of resources for climate adaptation.

Decision makers and land managers are increasingly required to manage landscapes for multiple purposes and benefits. However, despite progress in the development of frameworks linking natural capital to the provision of ecosystem services and human benefits there remains little guidance for how management interventions can improve ecosystem service provision. As ecosystem services cannot be directly influenced, interventions need to be directed toward natural capital stocks. We provide a framework that explicitly links natural capital stocks to ecosystem service provision and identify manageable attributes of natural capital stocks as the critical intervention point. A structured decision making process based on our framing of the ecosystem services concept can facilitate its application on the ground.

35Biodiversity offsetting is a mechanism aimed at achieving biodiversity gains to 36 compensate for the residual impacts of development activities on biodiversity. 37Estimating the ecological equivalence of biodiversity lost to development with that 38 gained by the offset requires a currency that captures the biota of interest and an 39 accounting model to evaluate the exchange. Ecologically robust, and user-friendly 40 decision support tools improve the transparency of biodiversity offsetting and assist in 41 the decision making process. Here we describe a tool developed for the New Zealand 42 Department of Conservation that offers a mechanism to transparently design and 43 evaluate biodiversity offsets intended to deliver no net loss. It is a relatively 44 disaggregated accounting model that balances like-for-like biodiversity trades using a 45 suite of area by condition currencies to calculate net present biodiversity value 46 (NPBV) to account individually for each measured biodiversity element of interest. 47The NPBV is used to evaluate whether a no net loss exchange is likely for each 48 biodiversity attribute. More disaggregated currencies have an advantage over 49 aggregated currencies (which use composite metrics) in that they account for each 50 itemised biodiversity element of concern. The disaggregated model we present can be 51 used to account for a variety of biodiversity types in an offset exchange, and for 52 different scales and complexities of development and impacts within both statutory 53 and voluntary frameworks. 54 55 Keywords biodiversity offsetting; disaggregated currencies; net present biodiversity 56 value 57 58 3

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We estimate public willingness to pay (WTP) for the benefits of carbon farming. Results show that Australians have a positive WTP for increasing native vegetation on farmland. Australians have a positive, but low, WTP for carbon storage in agricultural soils or vegetation. Reducing soil erosion (an intangible co-benefit of carbon farming) was not significant in respondents' preferences. We discuss the implications of our value estimates for climate change mitigation policies.

The planting of riparian margins is a policy option for pastoral farmers in response to land use induced environmental issues such as declining water quality, stream bank erosion, and loss of aquatic and terrestrial habitat. We elicited the views and experiences as to pros and cons of planting riparian margins from two sets of dairy farmers from Taranaki, New Zealand: those who are or have planted riparian margins, and those who have not yet done so. Those farmers who have planted riparian margins identified 21 positive aspects of riparian margin plantings and 11 negative aspects of riparian margin plantings. Perceived benefits identified by this group include water quality, increased biodiversity, the provision of cultural ecosystem services, immediate direct benefits to farm management and the farm system, and in some instances increased productivity on-farm. In contrast, those farmers that had fenced but not planted their riparian margins did not consider that riparian margin plantings could add further benefits to that which could be achieved by excluding stock from waterways, and associated only negative perceptions with riparian margin plantings. Planting riparian margins is not cost neutral and will not deliver anticipated environmental benefits in every situation. However, we argue that riparian margin plantings are an important ecological infrastructure investment that needs to be captured within a wider policy framework, the benefits of which extend beyond the mitigation of a single negative externality generated by land use practices, such as nutrient loss, and contribute to a multifunctional landscape.

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