Incentive-based strategies such as conservation easements and short-term management agreements are popular tools for conserving biodiversity on private lands. Billions of dollars are spent by government and private conservation organizations to support land conservation. Although much of conservation biology focuses on reserve design, these methods are often ineffective at optimizing the protection of biological benefits for conservation programs. Our review of the recent literature on protected-area planning identifies some of the reasons why. We analyzed the site-selection process according to three important components: biological benefits, land costs, and likelihood of land-use change. We compared our benefit-loss-cost targeting approach with more conventional strategies that omit or inadequately address either land costs or likelihood of land-use change. Our proposed strategy aims to minimize the expected loss in biological benefit due to future land-use conversion while considering the full or partial costs of land acquisition. The implicit positive correlation between the likelihood of land-use conversion and cost of land protection means high-vulnerability sites with suitable land quality are typically more expensive than low-vulnerability sites with poor land quality. Therefore, land-use change and land costs need to be addressed jointly to improve spatial targeting strategies for land conservation. This approach can be extended effectively to land trusts and other institutions implementing conservation programs.Economía y Cambio en el Uso de Suelo en la Priorización de la Conservación de Tierras Privadas Resumen: Las estrategias basadas en incentivos, como los derechos de conservación y los acuerdos de manejo a corto plazo, son herramientas populares para conservar la biodiversidad en tierras privadas. Las organizaciones conservacionistas gubernamentales y privadas gastan billones de dólares para financiar la conservación. Aunque la mayor parte de la biología de la conservación se centra en el diseño de reservas, estos métodos a menudo no son efectivos para laóptima protección de los beneficios biológicos de los programas de conservación. Nuestra revisión de la literatura reciente sobre planificación deáreas protegidas identifica algunas de las razones de lo anterior. Analizamos los procesos de selección de sitios en función de tres componentes importantes: beneficios biológicos, costo de las tierras y la probabilidad de cambio en el uso de suelo. Comparamos nuestro enfoque en el beneficio-pérdida-costo con métodos más tradicionales que omiten, o abordan inadecuadamente, el costo de las tierras y/o la probabilidad de cambio en el uso de suelo. La estrategia que proponemos trata de minimizar la pérdida esperada del beneficio biológico debido a la conversión del uso de suelo en el futuro al tiempo que considera los costos parciales o totales de la adquisición de tierras. La correlación positiva implícita entre la probabilidad de conversión en el uso de suelo y el costo de la protección de tierras signific...

Biofuels are widely touted as viable, albeit not straightforward, alternatives to petroleum-derived fuels. To best determine their utilization, many practitioners turn to life-cycle assessment (LCA) to ascertain the “environmental footprint”. Although parameters such as resource and land use, along with infrastructure, can be incorporated into LCA algorithms, many have noted that the methodological approach still needs careful attention. In this Feature, McKone et al. outline seven grand challenges that need to be engaged and surmounted to provide the best way forward for biofuel use.

The costly interactions between humans and wildfires throughout California demonstrate the need to understand the relationships between them, especially in the face of a changing climate and expanding human communities. Although a number of statistical and process-based wildfire models exist for California, there is enormous uncertainty about the location and number of future fires, with previously published estimates of increases ranging from nine to fifty-three percent by the end of the century. Our goal is to assess the role of climate and anthropogenic influences on the state’s fire regimes from 1975 to 2050. We develop an empirical model that integrates estimates of biophysical indicators relevant to plant communities and anthropogenic influences at each forecast time step. Historically, we find that anthropogenic influences account for up to fifty percent of explanatory power in the model. We also find that the total area burned is likely to increase, with burned area expected to increase by 2.2 and 5.0 percent by 2050 under climatic bookends (PCM and GFDL climate models, respectively). Our two climate models show considerable agreement, but due to potential shifts in rainfall patterns, substantial uncertainty remains for the semiarid inland deserts and coastal areas of the south. Given the strength of human-related variables in some regions, however, it is clear that comprehensive projections of future fire activity should include both anthropogenic and biophysical influences. Previous findings of substantially increased numbers of fires and burned area for California may be tied to omitted variable bias from the exclusion of human influences. The omission of anthropogenic variables in our model would overstate the importance of climatic ones by at least 24%. As such, the failure to include anthropogenic effects in many models likely overstates the response of wildfire to climatic change.

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Two commonly used forms for crop response to inputs are a smooth, differentiable production function and a linear response and plateau (LRP) model. This paper reconciles these two views by showing that smooth functions can be derived by aggregating the effects of heterogenous inputs on LRP functions. Data on com growth are used to test two specific aggregations.