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Wilcox discusses that study which reveals that wiregrass (Aristida beyrichiana), a fire-dependent foundational species there, can still flower 50 years after its last burn. The findings give hopes to ecologist that these unique ecosystems can be kept alive and brought back through controlled, prescribed burns.

Wildfires are often perceived as destructive disturbances, but we propose that when integrating evolutionary and socioecological factors, fires in most ecosystems can be understood as natural processes that provide a variety of benefits to humankind. Wildfires generate open habitats that enable the evolution of a diversity of shade-intolerant plants and animals that have long benefited humans. There are many provisioning, regulating, and cultural services that people obtain from wildfires, and prescribed fires and wildfire management are tools for mimicking the ancestral role of wildfires in an increasingly populated world.

Prescribed burning is a highly effective way to reduce wildfire risk; however, prescribed fires release harmful pollutants. Quantifying emissions from prescribed fires is valuable for atmospheric modeling and understanding impacts on nearby communities. Emissions are commonly reported as emission factors, which are traditionally calculated cumulatively over an entire combustion event. However, cumulative emission factors do not capture variability in emissions throughout a combustion event. Reliable emission factor calculations require knowledge of the state of the plume, which is unavailable when equipment is deployed for multiple days. In this study, we evaluated two different methods used to detect prescribed fire plumes: the event detection algorithm and a random forest model. Results show that the random forest model outperformed the event detection algorithm, with a detection accuracy of 61% and a 3% false positive rate, compared to 51% accuracy and a 31% false positive rate for the event detection algorithm. Overall, the random forest model provides more robust emission factor calculations and a promising framework for plume detection on future prescribed fires. This work provides a unique approach to fenceline monitoring, as it is one of the only projects to our knowledge using fenceline monitoring to measure emissions from prescribed fire plumes.

This paper investigates the prescribed-time coordination of networked robotic systems subject to complex unknowns including disturbances and actuator faults. A prescribed-time distributed estimator and extended state observer are proposed to acquire the leader’s information and complex unknowns, eliminating the need for prior knowledge of these unknowns and providing a promising approach for handling them within the prescribed time. To ensure the desired transient and steady-state responses, performance criteria are applied to coordination errors using a prescribed performance function. Subsequently, a hierarchical prescribed-time fault-tolerant control scheme is synthesized, consisting of a distributed estimator layer and a local control layer. The distinctive advantage of this hierarchical control scheme is that the coordination problem can be divided into two relatively simple sub-problems, namely coordination estimation and local robust tracking, easing control design and enhancing compatibility. Finally, simulation examples demonstrate the effectiveness of the theoretical results.

The Cerrado is a fire‐dependent savanna requiring a clear and urgent fire management policy. The extensive misuse of fire for deforestation or pasture management in Brazil has created an overall perception that its use is always deleterious. This view, reinforced by threats of global warming and climatic change, has lead to current policies of fire suppression. Cerrado ecosystems depend on the historical fire regime to maintain their structure, biodiversity and functioning. The suppression of fire has transformed savanna vegetation into forests, causing biodiversity losses and drastic changes in ecological processes. Policy implications. The National Fire Policy required by law must be urgently implemented in Brazil, including use of fire for Cerrado conservation in public and private lands on the basis of existing knowledge of indigenous people and scientists. Objective regulations on prescribed burning, land manager training, incentives for fire research and experimentation and a broad campaign to disseminate the benefits of fire for Cerrado conservation should be the cornerstones of the policy. If implemented, the policy can give the biodiversity of the Cerrado a future that has previously been severely threatened by fire suppression.

Dead wood (DW) provides critical habitat for thousands of species in forests, but its amount, quality and diversity have been heavily reduced by forestry. Therefore, interventions aiming to increase DW might be necessary to support its associated biodiversity, even in protected forests, which may be former production forests. Our aim was to synthesize the current state of knowledge drawn from replicated experimental studies into solid quantitative evidence of the effects of DW manipulation on forest biodiversity, with a focus on protected forests. We conducted a full systematic review of effects of DW manipulation on forest biodiversity in boreal and temperate regions. We included three intervention types: creation of DW from live trees at the site, addition of DW from outside the site and prescribed burning. Outcomes included abundance and species richness of saproxylic insects, ground insects, wood‐inhabiting fungi, lichens, reptiles and cavity‐nesting birds. In total, we included 91 studies, 37 of which were used in meta‐analyses. Although meta‐analysis outcomes were heterogeneous, they showed that increasing the amount of DW (“DW enrichment”) has positive effects on the abundance and richness of saproxylic insects and fungi. The positive effect on saproxylic pest insect abundance tended to be less than that on saproxylic insects in general. No significant effects were found for ground insects or cavity‐nesting birds. Although reviewed studies were mainly short term, our results support that management that increases DW amounts has the potential to increase the abundance of DW‐dependent species and, in most cases, also their species richness. Studies of burning showed positive effects on the abundance of saproxylic insects similar to those of other interventions, even though burning on average resulted in a smaller enrichment of DW amounts. Policy implications. The findings of the review suggest that manipulating dead wood (DW) can be an effective part of conservation management to support biodiversity in protected areas. The findings also indicate that the diversity of DW types is important, a mix of DW qualities should be favoured. Burning seems to be an effective method to increase biodiversity but to benefit cavity‐nesting birds, snag losses need to be minimized. Sammanfattning Död ved utgör ett viktigt habitat för tusentals skogslevande arter men mängden, kvaliteteten och dess diversitet har kraftigt minskat på grund av skogsbruket. Aktiva åtgärder som ökar mängden död ved kan därför bli nödvändigt för att förbättra situationen för arter kopplade till död ved. Dessa åtgärder kan även bli aktuella i skyddade skogar, varav många områden utgörs av skogar som har en historik av mänsklig påverkan. Vårt syfte med denna studie var att kvantitativt sammanfatta befintlig kunskap som handlar om död ved‐manipulation och dess inverkan på biodiversitet med huvudfokus på skyddade skogar. Vi har genomfört en komplett systematisk översiktssammanfattning om effekterna av död ved‐manipulation på biodoversiteten i tempererade och boreala skogar. Vi inkluderade tre typer av aktiva åtgärder: skapande eller adderande av död ved samt naturvårdsbränning. Vi inkluderade effekterna på förekomst och artmångfald av vedlevande insekter, marklevande insekter, vedlevande svampar, lavar, reptiler och hålhäckande fåglar. Vi hittade relevanta 91 studier och 37 av dessa användes i en meta‐analys. Resultaten från meta‐analysen visade på att en ökning av död ved hade en tydlig positiv effekt på både förekomst och artmångfald av vedlevande insekter och svampar. Förekomsten av vedlevande insekter som klassades som skadegörare ökade också men inte i samma utsträckning som vedlevande insekter totalt sett. Vi hittade ingen signifikant effekt på marklevande insekter eller hålhäckande fåglar. I de flesta studier som ingick i vår studie hade det gått endast en kort tid efter den aktiva åtgärden men resultaten visar ändå på att skötsel som ökar mängden död ved har potential att öka förekomst, samt i de flesta fall, även artförekomst, av arter kopplade till död ved. Även studierna som inkluderade naturvårdsbränning ökade förekomst av vedlevande insekter, trots att mängden död ved denna skötselmetod resulterade i var ungefär hälften jämfört med de övriga åtgärderna. Riktlinjer för praktiker: Denna studie visade på att åtgärder som ökar mängden död ved kan vara en effektiv naturvårdande skötselåtgärd som ökar biodiversiteten i skyddade skogar. Resultaten indikerar även att diversiteten av den döda veden är viktig och att en mix av kvalité bör gynnas. Naturvårdsbränning verkar vara en effektiv metod för att gynna biodiversitet men för att gynna hålhäckande fåglar bör torrakor skyddas.

The extent of wildfires cannot be easily mapped using field-based methods in areas with complex topography, and in those areas the use of remote sensing is an alternative. This study first obtained images from the Sentinel-2 satellites for the period 2015–2020 with the objective of applying multi-temporal spectral indices to assess areas burned in wildfires and prescribed fires in the Margalla Hills of Pakistan using the Google Earth Engine (GEE). Using those images, the Normalized Difference Vegetation Index (NDVI) and the Normalized Burn Ratio (NBR), which are often used to assess the severity of fires, were calculated for wildfires and prescribed fires. For each satellite image, spectral indices values were extracted for the 5th, 20th, 40th, 60th, 80th and 95th percentiles of pixels of each burned area. Then, boxplots representing the distribution of these values were plotted for each satellite image to identify whether the regeneration time subsequent to a fire, also known as the burn scar, and the severity of the fire differed between the autumn and summer wildfires, and with prescribed fires. A statistical test revealed no differences for the regeneration time amongst the three categories of fires, but that the severity of summer wildfires was significantly different from that of prescribed fire, and this, for both indices. Second, SAR images were obtained from the Sentinel-1 mission for the same period as that of the optical imagery. A comparison of the response of 34 SAR variables with official data on wildfires and prescribed fires from the Capital Development Authority revealed that the 95th percentile of the Normalized Signal Ratio (NSR p_95) was found to be the best variable to detect fire events, although only 50% of the fires were correctly detected. Nonetheless, when the occurrence of fire events according to the SAR variable NSR p_95 was compared to that from the two spectral indices, the SAR variable was found to correctly identify 95% of fire events. The SAR variable NSR p_95 is thus a suitable alternative to spectral indices to monitor the progress of wildfires and assess their severity when there are limitations to the use of optical images due to cloud coverage or smoke, for instance.

This paper proposes a new extended state observer-based sliding-mode control strategy with prescribed-time convergence. Firstly, a novel prescribed-time extended state observer is designed, which estimates the disturbance accurately within a prescribed time and effectively solves peaking value problem. Secondly, a new type of second-order prescribed-time sliding-mode controller is designed to ensure system states converge within a prescribed time. Then, the proposed control strategy is applied to the design of partial integrated guidance and control with two-loop controller structure. Finally, the validity of the proposed methodology is verified through numerical simulation.

Prescribed burning is a common strategy for minimizing forest fire risk. Fire is introduced under specific environmental conditions, with explicit duration, intensity, and rate of spread. Such conditions deviate from those encountered during the fire season. Prescribed burns mostly affect surface fuels and understory vegetation, an outcome markedly different when compared to wildfires. Data on prescribed burning are crucial for evaluating whether land management targets have been reached. This research developed a methodology to quantify the effects of prescribed burns using multi-temporal Sentinel-1 Synthetic Aperture Radar (SAR) imagery in the forests of southeastern Australia. C-band SAR datasets were specifically used to statistically explore changes in radar backscatter coefficients with the intensity of prescribed burns. Two modeling approaches based on pre- and post-fire ratios were applied for evaluating prescribed burn impacts. The effects of prescribed burns were documented with an overall accuracy of 82.3% using cross-polarized backscatter (VH) SAR data under dry conditions. The VV polarization indicated some potential to detect burned areas under wet conditions. The findings in this study indicate that the C-band SAR backscatter coefficient has the potential to evaluate the effectiveness of prescribed burns due to its sensitivity to changes in vegetation structure.