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From deforestation to forest recovery: perspectives for the Amazon under the rule of the Brazilian Forest Codede Barros Viana Hissa, Leticia 26 May 2021 (has links)
Die anhaltende Entwaldung tropischer Regenwälder und die damit einhergehenden sozialen und ökologischen Folgen finden zunehmend Beachtung nationaler Regierungen und zivilgesellschaftlicher Akteure, die Initiativen zur Verringerung der Entwaldung und Strategien zum Schutz von Lebensräumen und Artenvielfalt entwickelt haben. Die Waldrestaurierung, d.h. die Wiederherstellung von Waldökosystemen, stellt hierbei, neben der Verringerung der Entwaldung, ein entscheidendes Ziel dar. Brasilien spielt in diesem Zusammenhang eine entscheidende Rolle. Der Großteildes Amazonas-Regenwaldes, der größte zusammenhängende tropische Regenwald der Welt, liegt auf brasilianischem Gebiet. Nahezu 18% des brasilianischen Regenwaldes sind bereits gerodet. Landspekulation, Bergbau, und Landwirtschaft stellen die stärkste Bedrohung für die Existenz des Regenwaldes dar. Im Rahmen des Pariser Abkommens hat sich Brasilien dazu verpflichtet die Netto-Entwaldung bis 2030 zu stoppen und 12 Millionen Hektar Waldökosysteme wiederherzustellen. Eine zentrale Rolle für die Umsetzung der Verpflichtung kommt dem brasilianischen Waldschutzgesetz (BFC) zu, der wichtigsten brasilianischen Umweltgesetzgebung, die die Rahmenbedingungen für die Landnutzung auf privatem Landbesitz regelt. Im brasilianischen Amazon verlangt das BFC den Schutz von 80% der natürlichen Vegetation, als sogenanntes Legal Reserves (LRs). In der neusten Gesetzesversion von 2012 wurde erstmals der Umgang mit denjenigen Landbesitzern festgelegt, die den Gesetzesvorgaben nicht entsprechen. Es wird erwartet, dass die Umsetzung des neuen BFCs auf der einen Seite den Schutz der Wälder in den LRs gewährleistet und auf der andern Seite, unter Mitwirkung der Landbesitzer, zu ein großflächige Waldrestaurierung führt. Vor diesem Hintergrund ist das Ziel dieser Dissertation die Potenziale des BFC für den Schutz der Ur- und den nachwachsenden Wäldern zu ermitteln. Im Speziellen habe ich in der vorliegenden Dissertation (i) die Raum-Zeitlichen Veränderungen der Waldflächen im Einflussbereich der Bundesstraße BR-163, zwischen Cuiabá und Santarém, analysiert; (ii) das Potenzial der BFC für den Schutz der des Regenwaldes und für die Waldrestaurierung bewertet; und (iii) prioritäre Gebiete für ein großflächige Waldrestaurierung, unter Einbezug von Kosten, Biodiversität und Kohlenstoffspeicherung, identifiziert. Die Ergebnisse zeigen, dass ein Großteil der massiven Entwaldung in der Region zwischen Cuiabá und Santarém auf privaten Grundstücken stattfand. Dies lässt auf eine weitverbreitete Nichteinhaltung des BFCs schließen. Hohe Netto-Entwaldungsraten und eine rückläufige Verbreitung nachwachsenden Waldes deutet darauf hin, dass die Region weit von einer Trendwende von Netto-Waldverlust, zu Netto-Waldzuwachs entfernt ist. Um eine Ausbreitung der Wälder voranzutreiben, ist es daher notwendig, das Management der Ur- und nachwachsenden Wälder zu verbessern. Die Ergebnisse dieser Dissertation zeigen, dass mehr als 6 Millionen Hektar der derzeitigen Waldregeneration geschützt und ein Drittel der LR-Defizite ausgeglichen werden könnten, wenn die nachwachsenden Wälder in die Schutzzonen der LRs einbezogen werden. Die künftige Regulierung der BFC-Ausgleichsmechanismen wird einen entscheidenden Effekt auf die Waldrestaurierung und den Schutz der Urwälder haben. Die Analyse möglicher Regulierungs-Szenarien hat deutliche Variation zwischen prioritären Gebieten für die Waldrestaurierung in Mato Grosso gezeigt. Die Ergebnisse zeigen, dass die Waldrestaurierung auf privaten Grundstücken entscheidend für den Schutz von Biodiversität ist. Demgegenüber zeigt sich die Wiederherstellung von Waldökosystemen auf öffentlichem Land kostengünstiger und effektiver für die Kohlenstoffspeicherung. Die Ergebnisse demonstrieren die Relevanz detaillierter räumlicher Informationen zu Landbesitz und Landnutzungsänderungen, um die Auswirkungen von neuen rechtlichen Rahmenbedingungen für den Waldschutz und die Waldrestaurierung in tropischen Gebieten zu untersuchen. Die Schätzungen der derzeit nachwachsenden Waldflache, und dessen Schutzstatus, sind entscheidend um die nationalen Ziele der Waldrestaurierung zu erreichen. Die Ergebnisse verdeutlichen, dass ein besseres Management von nachwachsenden Waldökosystemen durch Bundes- und Landesgesetze notwendig ist, und neue Strategien und Mechanismen, die den Schutz nachwachsenden Wäldern sicherstellen, erarbeitet werden müssen. / Continued tropical forests decline has drawn concerted attention by governments and distinct sectors of the civil society, which have responded with anti-deforestation policies and conservation strategies. Alongside conservation, large-scale forest restoration is crucial for counteracting the negative impacts of deforestation on socio-ecological processes. In this context, Brazil plays a pivotal role. Most of the Amazon, the largest continuous tropical forest in the world, lies within the Brazilian territory. Nearly 18% of the Brazilian Amazon forest cover was already lost, and land speculation, mining, and agricultural expansion continue to threaten the forest. Therefore, cutting back land use change emissions is a major pillar of Brazil’s commitment to the Paris Agreement, which includes the plan to achieve zero net deforestation in the Amazon and restore 12Mha of forests countrywide by 2030. In this thesis I focused on the Brazilian Forest Code (BFC), the flagship environmental legislation governing land use in private lands of Brazil. In forestlands of the Amazon biome, the BFC requires the protection of 80% of the native vegetation as Legal Reserves (LRs). The latest version of the law, from 2012, also established the compliance conditions for past law offenders. Particularly, there are high expectations that the enforcement of the BFC will secure the protection of forests in LRs, and drive large-scale forest restoration. Therefore, my overall goal was to advance the knowledge about the potential of the BFC enforcement for the conservation of old- and regrowing forests in the Brazilian Amazon. Specifically, I (i) investigated the spatio-temporal patterns of net forest cover change for the influence area of the Cuiabá-Santarém highway, crossing the federal states of Pará and Mato Grosso in the Brazilian Amazon; (ii) evaluated the potential of the BFC enforcement for the protection of old and regrowing forests in the Brazilian Amazon, and estimated the contribution of regrowing forests for LRs demarcation; and (iii) applied a multicriteria analysis to map priority areas for large-scale forest restoration in private and public lands of Mato Grosso, contrasting the costs of restoration with the gains for biodiversity and carbon enhancement. Results show that the Cuiabá-Santarém focus region accumulated substantial deforestation, most of which on private lands, indicating a widespread non-compliance to the BFC. High net deforestation rates and decreasing prevalence of forest regrowth on deforested lands, indicates that this region is not near experiencing a turnaround from net forest losses to net forest gains. Hence, to promote forest expansion, it will be necessary to improve old- and regrowing forests governance. In this regard, results showed that if regrowing forests are included in LRs demarcation, over 6Mha of ongoing forest regeneration could be protected, and one third of LRs deficits could be offset. Also, the future regulation of BFC compensation mechanisms will be key for determining the potential of the law for promoting restoration and old-growth forests protection additionality. Finally, a substantial variation in the spatial distribution of priority areas for forest restoration was identified across Mato Grosso, and for different scenarios. Private properties were key to enhance intensively deforested habitats, while restoration in public lands was more effective in reducing restoration costs and mitigating carbon. The findings of this thesis demonstrate the importance of detailed spatial information on land tenure and land use change in tropical areas, to support spatial planning, and address the potential of legal frameworks for promoting forest conservation and restoration. The estimates of legal protection of current regrowing forests have strong implications for Brazil’s restoration targets. They call for an improved treatment of second-growth forests by federal and state legislations, and the creation of policy and mechanisms able to secure the protection of high-value regrowing forests.
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Evaluation of a Restoration Approach After One Century – Effects of Admixed European Beech on the Natural Regeneration Potential and Humus Condition in Spruce StandsAxer, Maximilian, Kluckow, Fabian, Wagner, Sven 02 February 2024 (has links)
About 100 years ago, groups of European beech were reintroduced into Norway spruce stands in some parts of Germany as a restoration approach. The aim of this approach was to maintain or rehabilitate the ecological function of soil fertility and the regeneration option of beech for the next generation. The effect of beech groups on surrounding spruce stands was studied in the Ore Mountains by recording natural regeneration of beech and humus layer thickness and form. Point pattern statistics were used to analyse the spread of beech regeneration and to determine factors influencing its establishment. It was found that the density of regeneration decreases with increasing distance from the beech group. However, beech regeneration was found up to distances of 69 m. Furthermore, it becomes evident that PAR radiation (maximum regeneration densities at PAR values of 35 W/m²) and fencing (3.41 times higher regeneration density compared to unfenced areas) against deer have a positive influence on beech regeneration density. Ordered categorical models were used to model humus form and non-linear models were used to model humus layer thickness. It could be proven that the most bioactive humus forms and lowest humus layer thicknesses were found within the beech group. With increasing distance to the beech group, the total humus layer thickness and the proportion of mormoder in the spruce stand increased. The positive influence of the beech group on the humus composition extends to about 40 m from the centre of the beech group. Due to the former arrangement of the beech groups in the terrain, the effects can also extend to the spruce stands in between. The hypotheses on the restoration approach of reintroducing groups of beech into spruce stands formulated by foresters 100 years ago can thus be confirmed. For future restoration approaches of spruce stands, groupwise mixtures of beech should be established with a distance of 40–50 m.
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Biomass and carbon stocks of the natural forests at Me Linh biodiversity station, Vinh Phuc province, Vietnam: Research articleDang, Thi Thu Huong, Do, Huu Thu 09 December 2015 (has links)
Biomass and carbon stock of the natural forests in Vietnam are still not clear due to limitation of knowledge and financial. In this paper, the results of estimating biomass and carbon stocks of the natural forests at Me Linh Biodiversity Station are shown. There are two forest types in this study: the forest vegetation restored after shifting cultivation (vegetation type I) and the forest vegetation restored after clear cutting exploitation (vegetation type II). As the results, the estimated biomass of the forest vegetation restored after shifting cultivation is 86.80 ton.ha-1 and the estimated biomass of the forest vegetation restored after clear cutting exploitation is higher, about 131.59 ton.ha-1. The carbon stock in plants was about 43.40 ton.ha-1 of vegetation type I and 65.79 ton.ha-1 of vegetation type II. The carbon storage in soil of vegetation type I is 79.01 ton.ha-1 and vegetation type II is 99.65 ton.ha-1. Hence, the total of carbon stock in forest vegetation I and II are accounted by 122.41ton.ha-1 and 165.44 ton.ha-1, respectively. In general, it can be pointed out that the naturally recovering secondary forest at Me Linh Station is the secondary young forest with the low economic value due to shortly restored process (about 10-20 years), the flora is not rich and abundant, and there are only commonly pioneer and light demanding tree species. / Sinh khối và trữ lượng các bon của rừng tự nhiên ở Việt Nam vẫn ít được quan tâm của do hạn chế về kiến thức và tài chính. Trong bài báo này, chúng tôi đưa ra kết quả của việc ước lượng sinh khối và tổng hợp các bon của các thảm thực vật rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Sinh học Mê Linh, tỉnh Vĩnh Phúc- Việt Nam, nơi có loại hình thảm thực vật chính, đó là thảm thực vật phục hồi sau nương rẫy (kiểu thảm thục vật I) và thảm thực vật phục hồi sau khai thác kiệt (kiểu thảm thực vật II) nhằm mục đích đánh giá tiềm năng của rừng thứ sinh tại khu vực nghiên cứu. Sinh khối của thảm thực vật phục hồi sau nương rẫy là 86,80 tấn/ha. Sinh khối của thảm thực vật phục hồi sau khai thác cao hơn, đạt 131.59 tấn/ha. Lượng các bon hấp thu trong đất của thảm thực vật I là 79,01 tấn/ha và thảm thực vật II là 99,65 tấn/ha. Như vậy, tổng lượng các bon được hấp thu trong mỗi loại hình thảm thực vật trên là: 122,41 tấn/ha (thảm thực vật I) và 165,14 tấn/ha. Nhìn chung, rừng thứ sinh phục hồi tự nhiên tại Trạm Đa dạng Mê Linh chủ yếu là rừng non thứ sinh, ít có giá trị kinh tế do quá trình phục hồi diễn ra ngắn (khoảng 10-20 năm) nên thành phần thực vật nghèo nàn, không phong phú, thành phần chính chủ yếu là các cây gỗ tiên phong, ưa sáng.
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Transcranial direct current stimulation (tDCS) for improving capacity in activities and arm function after stroke: a network meta-analysis of randomised controlled trialsElsner, Bernhard, Kwakkel, Gert, Kugler, Joachim, Mehrholz, Jan 06 June 2018 (has links) (PDF)
Background:
Transcranial Direct Current Stimulation (tDCS) is an emerging approach for improving capacity in activities of daily living (ADL) and upper limb function after stroke. However, it remains unclear what type of tDCS
stimulation is most effective. Our aim was to give an overview of the evidence network regarding the efficacy and safety of tDCS and to estimate the effectiveness of the different stimulation types.
Methods:
We performed a systematic review of randomised trials using network meta-analysis (NMA), searching the following databases until 5 July 2016: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, AMED, Web of Science, and four other databases. We included studies with adult people with stroke. We compared any kind of active tDCS (anodal, cathodal, or dual, that is applying anodal and cathodal tDCS concurrently) regarding improvement of our primary outcome of ADL capacity, versus control, after stroke.
PROSPERO ID: CRD42016042055.
Results:
We included 26 studies with 754 participants. Our NMA showed evidence of an effect of cathodal tDCS in improving our primary outcome, that of ADL capacity (standardized mean difference, SMD = 0.42; 95% CI 0.14 to 0.70). tDCS did not improve our secondary outcome, that of arm function, measured by the Fugl-Meyer upperextremity assessment (FM-UE). There was no difference in safety between tDCS and its control interventions, measured by the number of dropouts and adverse events.
Conclusion:
Comparing different forms of tDCS shows that cathodal tDCS is the most promising treatment option to improve ADL capacity in people with stroke.
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Transcranial direct current stimulation (tDCS) for improving capacity in activities and arm function after stroke: a network meta-analysis of randomised controlled trialsElsner, Bernhard, Kwakkel, Gert, Kugler, Joachim, Mehrholz, Jan 06 June 2018 (has links)
Background:
Transcranial Direct Current Stimulation (tDCS) is an emerging approach for improving capacity in activities of daily living (ADL) and upper limb function after stroke. However, it remains unclear what type of tDCS
stimulation is most effective. Our aim was to give an overview of the evidence network regarding the efficacy and safety of tDCS and to estimate the effectiveness of the different stimulation types.
Methods:
We performed a systematic review of randomised trials using network meta-analysis (NMA), searching the following databases until 5 July 2016: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, AMED, Web of Science, and four other databases. We included studies with adult people with stroke. We compared any kind of active tDCS (anodal, cathodal, or dual, that is applying anodal and cathodal tDCS concurrently) regarding improvement of our primary outcome of ADL capacity, versus control, after stroke.
PROSPERO ID: CRD42016042055.
Results:
We included 26 studies with 754 participants. Our NMA showed evidence of an effect of cathodal tDCS in improving our primary outcome, that of ADL capacity (standardized mean difference, SMD = 0.42; 95% CI 0.14 to 0.70). tDCS did not improve our secondary outcome, that of arm function, measured by the Fugl-Meyer upperextremity assessment (FM-UE). There was no difference in safety between tDCS and its control interventions, measured by the number of dropouts and adverse events.
Conclusion:
Comparing different forms of tDCS shows that cathodal tDCS is the most promising treatment option to improve ADL capacity in people with stroke.
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Testing of set recovery of unmodified and furfurylated densified wood by means of water storage and alternating climate testsBuchelt, Beate, Dietrich, Tobias, Wagenführ, André 23 June 2020 (has links)
Densification is a well-known method for improving the mechanical properties of wood. In the present study, unmodified and furfurylated wood samples were densified and submitted to cyclic water storage tests and cyclic alternating climate tests. Swelling coefficients and spring-back data were determined for the evaluation of the quality of densification. The study shows that results depend on the test method applied. Simple water storage tests do not reflect the behavior of densified wood in the high humidity range. The spring-back data of unmodified samples are more influenced by the testing method than those of the furfurylated ones.
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Stochastic Delay Cost Functions to Estimate Delay Propagation Under UncertaintyEvler, Jan, Schultz, Michael, Fricke, Hartmut, Cook, Andrew 20 March 2024 (has links)
We provide a mathematical formulation of flight-specific delay cost functions that enables a detailed tactical consideration of how a given flight delay will interact with all downstream constraints in the respective aircraft rotation. These functions are reformulated into stochastic delay cost functions to respect conditional probabilities and increasing uncertainty related to more distant operational constraints. Conditional probabilities are learned from historical operations data, such that typical delay propagation patterns can support the flight prioritization process as a part of tactical airline schedule recovery. A case study compares the impact of deterministic and stochastic cost functions on optimal recovery decisions during an airport constraint. We find that deterministic functions systematically overestimate potential disruption costs as well as optimal schedule recovery costs in high delay situations. Thus, an optimisation based on stochastic costs outperforms the deterministic approach by up to 15%, as it reveals ‘hidden’ downstream recovery potentials. This results in different slot allocations and in fewer passengers missing their connections.
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