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《Journal of Asia》2020,23(2):404-410
Wildfire is an important disturbance factor in forest ecosystem and could affect the distribution of insects. Because Monochamus beetles are known vector insects of pine wood nematodes in Korea and burnt pine trees can be used as oviposition habitats for Monochamus beetles, we investigated changes in the spatial (among fire severity classes) and temporal (between years) distributions of M. alternatus and M. saltuarius. From late May 2017 to early October 2018, four multi-funnel traps with pheromone lure were installed in each fire severity class (unburned, light, light-moderate edge, moderate-severe edge, and severe). All traps were replaced fortnightly from May to October for two years. The spatial distribution of the two Monochamus beetles was significantly affected by fire severity. In particular, M. alternatus showed higher catches in the severely burned sites and responded positively to the fire. A similar number of M. saltuarius individuals were observed between 2017 and 2018, while more M. alternatus were caught in 2018 compared to 2017. Consequently, it was confirmed that the dead wood of P. densiflora caused by the wildfire had a great influence on the density of insects, especially M. alternatus.  相似文献   
144.
To address the need for more holistic approaches to ecological management and restoration, we examine ecosystem interventions through the lens of systems thinking and in reference to systems archetypes, as developed in relation to organizational management in the business world. Systems thinking is a holistic approach to analysis that focuses on how a system's constituent parts interrelate and how systems work over time and within the context of larger systems. Systems archetypes represent patterns of behavior that have been observed repeatedly. These archetypes help relate commonly observed responses to environmental problems with their effect on important feedback processes to better anticipate connections between actions and results. They highlight situations where perceived solutions actually result in worse or unintended consequences, and where changing goals may be either appropriate or inappropriate. The archetypes can be applied to practical examples, and can provide guidance to help make appropriate intervention decisions in similar circumstances. Their use requires stepping back from immediately obvious management decisions and taking a more systemic view of the situation. A catalog of archetypes that describe common patterns of systems behavior may inform management by helping to diagnose system dynamics earlier and identifying interactions among them.  相似文献   
145.
Biocrusts are multifunctional communities that are increasingly being used to restore degraded or damaged ecosystems. Concurrently, restoration science is shifting away from the use of purely structural metrics, such as relative abundance, to more functional approaches. Although biocrust restoration technology is advancing, there is a lack of readily available information on how to monitor biocrust functioning and set appropriate restoration goals. We therefore compiled a selection of 22 functional indicators that can be used to monitor biocrust functions, such as CO2 exchange as an indicator of productivity or soil aggregate stability as a proxy for erosion resistance. We describe the functional importance of each indicator and the available protocols with which it may be measured. The majority of indicators can be measured as a functional trait of species by using patches of biocrust or cultures that contain only one species. Practitioners wishing to track the multifunctionality of an entire biocrust community would be advised to choose one indicator from each broad functional group (erosion resistance, nutrient accumulation, productivity, energy balance, hydrology), whereas a targeted approach would be more appropriate for projects with a key function of interest. Because predisturbance data are rarely available for biocrust functions, restoration goals can be based on a closely analogous site, literature values, or an expert elicitation process. Finally, we advocate for the establishment of a global trait database for biocrusts, which would reduce the damage resulting from repeated sampling, and provide a wealth of future research opportunities.  相似文献   
146.
The role of herbivorous fish in threatening marine forests of temperate seas has been generally overlooked. Only recently, the scientific community has highlighted that high fish herbivory can lead to regime shifts from canopy‐forming algae to less complex turf communities. Here, we present an innovative herbivorous fish deterrent device (DeFish), which can be used for conservation and restoration of marine forests. Compared to most traditional fish exclusion systems, such as cages, the DeFish system does not need regular cleaning and maintenance, making it more cost‐efficient. Resistance of DeFish was tested by installing prototypes at different depths in the French Riviera and in Montenegro: more than 60% of the devices endured several years without maintenance, even if most of them were slightly damaged in the exposed site in Montenegro. The efficacy of DeFish in limiting fish herbivory was tested by an exclusion experiment on Cystoseira amentacea in the French Riviera. In a few months, the number of fish bite marks on the seaweed was decreased, causing a consequent increase in algal length. The device here presented has been conceived for Mediterranean canopy‐forming algae, but the same concept can be applied to other species vulnerable to fish herbivory, such as kelps or seagrasses. In particular, the DeFish design could be improved using more robust and biodegradable materials. Innovative engineering systems, such as DeFish, are expected to become useful tools in the conservation and restoration of marine forests, to complement other practices including active reforestation, herbivore regulation, and regular monitoring of their status.  相似文献   
147.
The restoration community continues to discuss what constitutes good environmental stewardship. One area of tension is the extent to which the well‐being of wild animals should inform restoration efforts. We discuss three ways that the perspective of wild animal welfare can augment restoration ecology: strengthening people's relationship with nature, reinforcing biotic integrity, and reducing mechanistic uncertainty. The animal welfare movement elevates sentient animals as stakeholders and explores how environmental context directly impacts the well‐being of individuals. Viewing wild animals through this lens may encourage people to think and act with empathy and altruism. Second, we incorporate animal welfare into the concept of biotic integrity for ecological and ethical reasons. Restoring ecosystem processes may enhance animal welfare, and vice versa. Alternatively, there may be a trade‐off between these factors, requiring local decision‐makers to prioritize between restoring ecosystem function and promoting individuals' well‐being. We conclude by discussing how welfare can impact population recovery, thereby adding insights about mechanisms underpinning restoration objectives. Ultimately, restoration ecologists and proponents of wild animal welfare could enjoy a productive union.  相似文献   
148.
Sea water temperature affects all biological and ecological processes that ultimately impact ecosystem functioning. In this study, we examine the influence of temperature on global biomass transfers from marine secondary production to fish stocks. By combining fisheries catches in all coastal ocean areas and life‐history traits of exploited marine species, we provide global estimates of two trophic transfer parameters which determine biomass flows in coastal marine food web: the trophic transfer efficiency (TTE) and the biomass residence time (BRT) in the food web. We find that biomass transfers in tropical ecosystems are less efficient and faster than in areas with cooler waters. In contrast, biomass transfers through the food web became faster and more efficient between 1950 and 2010. Using simulated changes in sea water temperature from three Earth system models, we project that the mean TTE in coastal waters would decrease from 7.7% to 7.2% between 2010 and 2100 under the ‘no effective mitigation’ representative concentration pathway (RCP8.5), while BRT between trophic levels 2 and 4 is projected to decrease from 2.7 to 2.3 years on average. Beyond the global trends, we show that the TTEs and BRTs may vary substantially among ecosystem types and that the polar ecosystems may be the most impacted ecosystems. The detected and projected changes in mean TTE and BRT will undermine food web functioning. Our study provides quantitative understanding of temperature effects on trophodynamic of marine ecosystems under climate change.  相似文献   
149.
Numerous studies have demonstrated that fertilization with nutrients such as nitrogen, phosphorus, and potassium increases plant productivity in both natural and managed ecosystems, demonstrating that primary productivity is nutrient limited in most terrestrial ecosystems. In contrast, it has been demonstrated that heterotrophic microbial communities in soil are primarily limited by organic carbon or energy. While this concept of contrasting limitations, that is, microbial carbon and plant nutrient limitation, is based on strong evidence that we review in this paper, it is often ignored in discussions of ecosystem response to global environment changes. The plant‐centric perspective has equated plant nutrient limitations with those of whole ecosystems, thereby ignoring the important role of the heterotrophs responsible for soil decomposition in driving ecosystem carbon storage. To truly integrate carbon and nutrient cycles in ecosystem science, we must account for the fact that while plant productivity may be nutrient limited, the secondary productivity by heterotrophic communities is inherently carbon limited. Ecosystem carbon cycling integrates the independent physiological responses of its individual components, as well as tightly coupled exchanges between autotrophs and heterotrophs. To the extent that the interacting autotrophic and heterotrophic processes are controlled by organisms that are limited by nutrient versus carbon accessibility, respectively, we propose that ecosystems by definition cannot be ‘limited’ by nutrients or carbon alone. Here, we outline how models aimed at predicting non‐steady state ecosystem responses over time can benefit from dissecting ecosystems into the organismal components and their inherent limitations to better represent plant–microbe interactions in coupled carbon and nutrient models.  相似文献   
150.
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation.  相似文献   
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