Conservation Letters最新文献

World forests face many threats, including wildfires, with tremendous ecological, social, and economic implications. Mediterranean ecosystems have evolved in the presence of fire, but changes to fire regimes associated with other global changes pose new challenges to postfire community regeneration. Forest regeneration largely depends on plant adaptations to survive wildfires or on the recolonization of burnt areas through seed dispersal. However, the value of the service provided by wild animals to postfire forest regeneration remains unevaluated. Here, we estimate the economic value of the biotic seed dispersal service in postfire restoration in Portugal. We combine budgeted costs of governmental Emergency Stabilisation Reports with network analysis that estimates the dependency of the Portuguese flora on biotic seed dispersal and on alternative fire regeneration strategies. Replacing the services provided by seed dispersers during postfire regeneration of Portuguese forests would cost 23,061,621€/year, highlighting the need for integrative policies that promote resilient forests.

Negative landscape-scale fragmentation effects are often inferred from negative patch-scale edge effects. I tested this cross-scale extrapolation using two evaluations. First, I searched for studies that estimated the direction of both a patch-scale edge effect and a landscape-scale fragmentation effect. The directions were concordant and discordant in 55% and 45% of cases, respectively. Second, I extracted from the literature a sample of landscape-scale fragmentation effects on individual species. Then, for each species I searched for studies from which I could calculate the slope of its patch-scale edge effect. Species showing negative patch-scale edge effects were nearly equally likely to show negative or positive landscape-scale fragmentation effects, and likewise for species showing positive patch-scale edge effects. The results mean that the efficacy of policies related to habitat fragmentation cannot be inferred from observed patch-scale edge effects. Such policies require landscape-scale evidence, comparing species' responses in landscapes with different levels of fragmentation.

Biological invasions represent one of the major threats to the world's biodiversity. National and international efforts are taken to address the complexity and dynamic of invasions in legislation. However, based on the Polish experience of implementing the European Union's regulation on invasive alien species (IAS), we suggest that an unclear and disorganized process of law implementation results in the regulations being counterproductive. We describe how a well-planned policy can become a burden impeding effective research and, consequently, scientific feedback to improve the policy. The results of our study suggest that there is a large scale of scientists' noncompliance with new legal requirements. For many researchers, the implementation of the new IAS regulation was changing the rules in the middle of the game. Researchers strictly following the new regulations must wait for the relevant permits and may risk the successful completion of their projects. Conversely, researchers who prioritize project completion may be forced to continue their research violating the law. We argue that this example of implementing the new IAS regulation illustrates the need to include some intermediate solutions providing more flexibility and time for researchers to adjust to policy change, thus minimizing the negative impacts of the new legislature on scientific progress.

Offsetting policies have increased worldwide, utilizing a range of biodiversity metrics to compensate for development impacts. We conducted a global analysis of offset legislation by reviewing policies from 108 countries, which have voluntary offsets, or which require offsets by law. We sought to understand how well biodiversity metrics and offset currencies are documented in current policies. Where biodiversity metrics are documented we aimed to understand how metrics were scored, combined, and multiplied to create offset currencies. We found only 22 jurisdictions (from 14 countries) had guidelines documenting how biodiversity should be assessed during offsetting, representing a significant gap in the guidance available for offsets. Of the 22 guidelines, 14 (63%) documented use of aggregated currencies, eight (23%) did not aggregate biodiversity metrics into a single currency, and three (17%) did not specify either approach. Habitat type and condition, as well as area, were widely recommended across policies (>50%). Where species-level metrics were considered, guidelines generally focused on habitat distributions rather than abundance or population metrics. The lack of consistent and clear guidance about how biodiversity should be measured in offsets reduces our ability to determine the effectiveness of offsets in compensating for development impacts long term.