Ecological restoration is widely used to reverse the environmental degradation caused by human activities. However, the effectiveness of restoration actions in increasing provision of both ...biodiversity and ecosystem services has not been evaluated systematically. A meta-analysis of 89 restoration assessments in a wide range of ecosystem types across the globe indicates that ecological restoration increased provision of biodiversity and ecosystem services by 44 and 25%, respectively. However, values of both remained lower in restored versus intact reference ecosystems. Increases in biodiversity and ecosystem service measures after restoration were positively correlated. Results indicate that restoration actions focused on enhancing biodiversity should support increased provision of ecosystem services, particularly in tropical terrestrial biomes.
Cultivation and cropping are major causes of destruction and degradation of natural ecosystems throughout the world. We face the challenge of maintaining provisioning services while conserving or ...enhancing other ecosystem services and biodiversity in agricultural landscapes. There is a range of possibilities within two types of intervention, namely "land sharing" and "land separation"; the former advocates the enhancement of the farmed environment, but the latter a separation between land designated for farming versus conservation. Land sharing may involve biodiversity-based agricultural practices, learning from traditional farming, changing from conventional to organic agriculture and from "simple" crops and pastures to agro-forestry systems, and restoring or creating specific elements to benefit wildlife and particular services without decreasing agricultural production. Land separation in the farmland context involves restoring or creating non-farmland habitat at the expense of field-level agricultural production—for example, woodland on arable land. Restoration by land sharing has the potential to enhance agricultural production, other ecosystem services and biodiversity at both the field and landscape scale; however, restoration by land separation would provide these benefits only at the landscape scale. Although recent debate has contrasted these approaches, we suggest they should be used in combination to maximize benefits. Furthermore, we suggest "woodland islets", an intermediate approach between land abandonment and farmland afforestation, for ecological restoration in extensive agricultural landscapes. This approach allows reconciliation of farmland production, conservation of values linked to cultural landscapes, enhancement of biodiversity, and provision of a range of ecosystem services. Beyond academic research, restoration projects within agricultural landscapes are essential if we want to halt environmental degradation and biodiversity loss.
Ferrierite zeolites with nanosized crystals and external surface areas higher than 250 m2 g−1 have been prepared at relatively low synthesis temperature (120 °C) by means of the collaborative effect ...of two organic structure directing agents (OSDA). In this way, hierarchical porosity is achieved without the use of post‐synthesis treatments that usually involve leaching of T atoms and solid loss. Adjusting the synthesis conditions it is possible to decrease the crystallite size in the directions of the 8‐ and 10‐ring channels, 010 and 001 respectively, reducing their average pore length to 10–30 nm and increasing the number of pores accessible. The small crystal size of the nano‐ferrierites results in an improved accessibility of reactants to the catalytic active centers and enhanced product diffusion, leading to higher conversion and selectivity with lower deactivation rates for the oligomerization of 1‐pentene into longer‐chain olefins.
Short channels: Nanocrystalline ferrierites with reduced crystal dimensions along the 10‐ring channels are synthesized. They are efficient and stable catalysts for the oligomerization of 1‐pentene to diesel as a result of the decreased diffusional path lengths.
Restoration and repair of Earth’s damaged ecosystems Jones, Holly P.; Jones, Peter C.; Barbier, Edward B. ...
Proceedings - Royal Society. Biological sciences/Proceedings - Royal Society. Biological Sciences,
02/2018, Volume:
285, Issue:
1873
Journal Article
Peer reviewed
Open access
Given that few ecosystems on the Earth have been unaffected by humans, restoring them holds great promise for stemming the biodiversity crisis and ensuring ecosystem services are provided to ...humanity. Nonetheless, few studies have documented the recovery of ecosystems globally or the rates at which ecosystems recover. Even fewer have addressed the added benefit of actively restoring ecosystems versus allowing them to recover without human intervention following the cessation of a disturbance. Our metaanalysis of 400 studies worldwide that document recovery from large-scale disturbances, such as oil spills, agriculture and logging, suggests that though ecosystems are progressing towards recovery following disturbances, they rarely recover completely. This result reinforces conservation of intact ecosystems as a key strategy for protecting biodiversity. Recovery rates slowed down with time since the disturbance ended, suggesting that the final stages of recovery are the most challenging to achieve. Active restoration did not result in faster or more complete recovery than simply ending the disturbances ecosystems face. Our results on the added benefit of restoration must be interpreted cautiously, because few studies directly compared different restoration actions in the same location after the same disturbance. The lack of consistent value added of active restoration following disturbance suggests that passive recovery should be considered as a first option; if recovery is slow, then active restoration actions should be better tailored to overcome specific obstacles to recovery and achieve restoration goals.We call for a more strategic investment of limited restoration resources into innovative collaborative efforts between scientists, local communities and practitioners to develop restoration techniques that are ecologically, economically and socially viable.
Scrambling is the process by which information stored in local degrees of freedom spreads over the many-body degrees of freedom of a quantum system, becoming inaccessible to local probes and ...apparently lost. Scrambling and entanglement can reconcile seemingly unrelated behaviors including thermalization of isolated quantum systems and information loss in black holes. Here, we demonstrate that fidelity out-of-time-order correlators (FOTOCs) can elucidate connections between scrambling, entanglement, ergodicity and quantum chaos (butterfly effect). We compute FOTOCs for the paradigmatic Dicke model, and show they can measure subsystem Rényi entropies and inform about quantum thermalization. Moreover, we illustrate why FOTOCs give access to a simple relation between quantum and classical Lyapunov exponents in a chaotic system without finite-size effects. Our results open a path to experimental use FOTOCs to explore scrambling, bounds on quantum information processing and investigation of black hole analogs in controllable quantum systems.
Interacting spin systems are of fundamental relevance in different areas of physics, as well as in quantum information science and biology. These spin models represent the simplest, yet not fully ...understood, manifestation of quantum many-body systems. An important outstanding problem is the efficient numerical computation of dynamics in large spin systems. Here, we propose a new semiclassical method to study many-body spin dynamics in generic spin lattice models. The method is based on a discrete Monte Carlo sampling in phase space in the framework of the so-called truncated Wigner approximation. Comparisons with analytical and numerically exact calculations demonstrate the power of the technique. They show that it correctly reproduces the dynamics of one- and two-point correlations and spin squeezing at short times, thus capturing entanglement. Our results open the possibility to study the quantum dynamics accessible to recent experiments in regimes where other numerical methods are inapplicable.
We investigate collective emission from coherently driven ultracold (88)Sr atoms. We perform two sets of experiments using a strong and weak transition that are insensitive and sensitive, ...respectively, to atomic motion at 1 μK. We observe highly directional forward emission with a peak intensity that is enhanced, for the strong transition, by >10(3) compared with that in the transverse direction. This is accompanied by substantial broadening of spectral lines. For the weak transition, the forward enhancement is substantially reduced due to motion. Meanwhile, a density-dependent frequency shift of the weak transition (∼10% of the natural linewidth) is observed. In contrast, this shift is suppressed to <1% of the natural linewidth for the strong transition. Along the transverse direction, we observe strong polarization dependences of the fluorescence intensity and line broadening for both transitions. The measurements are reproduced with a theoretical model treating the atoms as coherent, interacting radiating dipoles.
Two billion ha have been identified globally for forest restoration. Our meta-analysis encompassing 221 study landscapes worldwide reveals forest restoration enhances biodiversity by 15-84% and ...vegetation structure by 36-77%, compared with degraded ecosystems. For the first time, we identify the main ecological drivers of forest restoration success (defined as a return to a reference condition, that is, old-growth forest) at both the local and landscape scale. These are as follows: the time elapsed since restoration began, disturbance type and landscape context. The time elapsed since restoration began strongly drives restoration success in secondary forests, but not in selectively logged forests (which are more ecologically similar to reference systems). Landscape restoration will be most successful when previous disturbance is less intensive and habitat is less fragmented in the landscape. Restoration does not result in full recovery of biodiversity and vegetation structure, but can complement old-growth forests if there is sufficient time for ecological succession.
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