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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Waldmehrungspolitik in der Region Leipzig

Schneider, Hans Hermann 18 January 2013 (has links) (PDF)
Die Gegend um Leipzig stellt sachsenweit die waldärmste Region dar. Vor diesem Hintergrund verwundert es nicht, dass landesweite Pläne und Programme den Schwerpunkt der Waldvermehrung in Sachsen strikt in diese Region lenken, in der mittlerweile seit über 30 Jahren um mehr Wald gerungen wird. Auch die aktuellste Fassung des Landesentwicklungs-plans 2012, gegenwärtig noch als Entwurf vorliegend, verweist auf die Leipziger Region, wenn es darum geht, den im Bundesvergleich unterdurchschnittlichen Waldanteil Sachsens von gegenwärtig 28,5 % auf 30 % der Landesfläche zu erhöhen. Potential wird hierbei vor allem in der sich immer noch in Rekultivierung befindlichen Bergbaufolgelandschaft des Leipziger Südens sowie in der ausgeräumten Agrarlandschaft des ländlich geprägten Raums gesehen. Initiativen und Bestrebungen, den Waldanteil der Region langfristig zu erhöhen, sind tief in der Geschichte verankert und werden von den verschiedensten Akteuren getragen. In den 1970er Jahren waren es die Staatlichen Forstbetriebe, die im Zuge der Sanierung einer devastierten Tagebaulandschaft ausgedehnte Waldgebiete neu entstehen ließen und der Bevölkerung im Ballungsraum Leipzig damit wieder eine attraktive Erholungslandschaft schaffen wollten. Ab Mitte der 90er Jahre ging der Zuwachs neuer Waldgebiete spürbar zurück und beschränkt sich seit dem auf die Aufforstung kleinerer Flächen in Streulagen. Aus der Sicht vieler Forstfachleute wird diese Tatsache als äußerst unbefriedigend eingeschätzt. Mittlerweile besteht dagegen die Vermutung, dass sich der jährliche Waldflächenzuwachs in der Waage mit einem zunehmenden Waldflächenverlust hält und dass das ursprüngliche Ziel der Waldmehrung dem der Erhaltung des vorhandenen Waldes gewichen ist. Aus diesem Grunde haftet der Region um Leipzig zunehmend das Charakteristikum einer planungs-dynamischen Region an, in der in kurzer Zeit Flächennutzungsarten wechseln und Pläne geändert werden. Erschwert wird die Waldvermehrung aber nicht nur durch wirtschaftliche und Gemeinwohlinteressen, sondern vor allem durch naturschutzrechtliche Vorgaben der Europäischen Union, die "runtergebrochen" auf die Regionalebene zu erheblichen Konflikten im Bestreben um mehr Wald führen. Hinzu kommt ein enorm wachsender Flächenverlust, so dass Landwirte der Region zunehmend nicht mehr bereit sind, ihr wertvolles Ackerland für eine Aufforstung bereit zu stellen. Ein eigens dafür konstruiertes, agrarpolitisches Förderinstrument der Europäischen Union, das landwirtschaftliche Flächennutzer zu einer Aufforstung auf ihrem Grund und Boden bewegen und die Waldvermehrung in Sachsen vorantreiben soll, wird kaum in Anspruch genommen.
112

Problems of rehabilitating the Tillamook burn /

Kallander, R. M. January 1953 (has links)
Thesis (M.F.)--Oregon State College, 1953. / Typescript. Includes bibliographical references (leaves 82-83). Also available on the World Wide Web.
113

Instability in plantations of container-grown Scots pine and consequences on stem form and wood properties /

Rune, Göran, January 2003 (has links)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
114

Effects of land use changes on soil quality and native flora degradation and restoration in the highlands of Ethiopia : implications for sustainable land management /

Mulugeta Lemenih, January 2004 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 5 uppsatser.
115

Regeneration methods to reduce pine weevil damage to conifer seedlings /

Petersson, Magnus, January 2004 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.
116

Post-hurricane growth and recruitment of plant species used by birds in northern Puerto Rico /

Sustache Sustache, José A. January 2004 (has links) (PDF)
Thesis (M.S.)--University of Puerto Rico, Mayagüez Campus, 2004. / Tables. Printout. Abstract in English and Spanish. Includes bibliographical references (leaves 30-38).
117

Un essai d'utilisation d'information écologique à l'aide d'un sig dans une perspective d'aménagement intégré d'un territoire forestier : le cas de Girardville /

Boucher, Brigitte, January 1996 (has links)
Mémoire (M.Ress.Renouv.)--Université du Québec à Chicoutimi, 1996. / Document électronique également accessible en format PDF. CaQCU
118

Evaluation of willow oak acorn production and the effects of midstory control and flooding on underplanted willow oak seedlings in two Arkansas greentree reservoirs

Thornton, Rory Owen, January 2009 (has links)
Thesis (M.S.)--Mississippi State University. Department of Forestry. / Title from title screen. Includes bibliographical references.
119

Evolução da área florestada na região de Botucatu-SP no período de 1996 a 2008 visando à implantação da reserva legal

Cataneo, Pedro Fernando [UNESP] 20 May 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-20Bitstream added on 2014-06-13T20:42:08Z : No. of bitstreams: 1 cataneo_pf_dr_botfca.pdf: 450727 bytes, checksum: ced9415722d79c8365a2f81f996d9e7f (MD5) / A região de Botucatu tem tradição na indústria de exploração madeireira e possui grandes áreas de mata natural e de reflorestamento. Devido às atuais discussões sobre a Reserva Legal, este trabalho tem por objetivo conhecer a distribuição das áreas agrícolas da região em suas variadas explorações, com especial ênfase às áreas de mata natural, comparar os valores municipais com aqueles dispostos no Código Florestal Brasileiro, de forma a analisar o processo de implantação dos 20% de área de florestas em relação à área total agrícola, em nível macro municipal e regional, sem considerar as áreas de cada uma das propriedades agrícolas e nem a bacia hidrográfica às quais pertencem. Os resultados do trabalho, desenvolvido com dados secundários do projeto LUPA da Secretaria da Agricultura do Estado de São Paulo, relativos aos anos 1995/1996 e 2007/2008, mostram que todos os municípios pertencentes à região não possuem áreas de mata natural iguais ou superiores aos 20% da área total e que portanto terão que reflorestar sem finalidade exploratória, a não ser cumprir os preceitos da legislação; que o município de Pereiras apresentou no período de 1996 a 2008 leve involução na área de mata natural; que não levando em consideração possíveis incrementos futuros na área total agrícola, os municípios de Areiópolis e, em seguida, Pratânia, terão de aumentar a taxa de reflorestamento em relação à taxa de regeneração da mata natural efetiva entre 1996 e 2008, visando a atingir os 20% da área total com matas naturais ou com florestas que não venham a ser exploradas e que dentre estas, a maior velocidade deverá ser implementada pelo município de Areiópolis; que o município de Itatinga e, em menor magnitude o de Pardinho terão que empregar taxas de implantação... / The region of Botucatu, Brazil, is traditionally known for its logging industries and has large natural and reforested forests. Due to the considerations on the Legal Forest Reserve, the aim of this paper is to show the distribution of the farming areas in the region and their application – especially natural forests. Also, to compare the municipal values with those stated in the Brazilian Forestry Code in order to analyze the process of implementing 20% of forest area in relation to the total farming area, at municipal and regional levels, not considering the areas of each of the farms nor the watershed to which they belong. The work results – developed from secondary data from the LUPA Project of the State of São Paulo Department of Agriculture, years of 1995/1996 and 2007/2008 – show that all municipalities in the region of Botucatu do not have forest areas equal to or greater than 20% of total area. Therefore, a non-exploratory reforestation procedure will have to be implemented to follow legal requirements. The results also show that the municipality of Pereiras presented – from 1996 to 2008 – a slight regression in the area of natural forest; that the municipalities of Areiópolis and Pratânia will have to increase the reforestation rate over the regeneration rate of the effective natural forest area between 1996 and 2008 in order to achieve the 20% of total area with natural forests or forests which will not be explored – not taking into consideration, though, future farming increments. Still, Areiópolis will have to implement it the fastest. The results also show that the municipality of Itatinga – and, to a lesser extent, the municipality of Pardinho – will need to employ a lower implementation rate than the one verified in the effective regeneration of forests between... (Complete abstract click electronic access below)
120

Lodo de Estação de Tratamento de Água na composição de substratos para produção de mudas de plantas da Caatinga

Augusto, José 18 March 2013 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2017-07-19T13:51:18Z No. of bitstreams: 1 arquivototal.pdf: 2295083 bytes, checksum: e20fa5c46199252b1023df7551ab39d9 (MD5) / Made available in DSpace on 2017-07-19T13:51:18Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2295083 bytes, checksum: e20fa5c46199252b1023df7551ab39d9 (MD5) Previous issue date: 2013-03-18 / The water treatment process creates a high amount of sludge. Because of that, sludge disposal alternatives should be studied based on technical, economic, environmental, social and political aspects. The present study aimed to evaluate the use of water treatment plant sludge in the composition of substrates for production of seedlings from typical plants of the Caatinga vegetation. Experiments composed of angico, aroiera and sabiá seedling production were carried out at the Experimental Farm of the Federal Institute of Education, Science and Technology of Paraiba (IFPB) - Sousa campus, state of Paraíba, Brazil, between February and May 2015. For each plant species, an experiment using randomized block design was performed. Each experiment consisted of 5 substrates (S1: 70% soil + 30% bovine manure + 0% WTP sludge; S2: 65% soil + 25% bovine manure + 10 % WTP sludge; S3: 60% soil + 20% bovine manure + 20% WTP sludge; S4: 55% soil + 15% bovine manure + 30% WTP sludge and S5: 50% soil + 10% bovine manure + 40% WTP sludge) and 4 repetitions. The evaluated characteristics were: germination (G), stem diameter (SD), shoot height (H), length of the main root (LMR), dry weight of shoot (DWS), dry mass of roots (DMR) total dry matter (TDM), ratio between shoot height and stem diameter (H/SD), ratio between dry weight of shoot and dry mass of roots (DWS/DMR) and Quality Dickson Index (QDI). For the angico seedlings, it was found high values of SD, H, DWS, TDM and H/SD when the substrates 2, 3, 4 and 5 were used. For the other variables, similar results were observed. The aroeira seedlings presented high values of SD when substrates 3, 4 and 5 were used, which is similar to the other studied characteristics. With regard to the sabiá seedlings, there was not substrate influence over the variables. The studied water treatment plant sludge can be used as part of substrates for angico, aroeira and sabiá seedlings production, composing up to 40%. / O processo de tratamento de água gera elevada quantidade de lodo, cuja disposição deve ser estudada em função de aspectos técnicos, econômicos, ambientais, sociais e políticos. Objetivou-se avaliar a utilização do lodo de Estação de Tratamento de Água na composição de substratos para produção de mudas de plantas da Caatinga. Na Fazenda Experimental do Instituto Federal de Educação, Ciência e Tecnologia da Paraíba - Campus Sousa (6° 50‟ 33” S e 38° 17‟ 54” W, 264 m de altitude), no período de fevereiro a maio de 2015, realizou-se experimentos consistindo da produção de mudas de angico (Anadenanthera macrocarpa (Benth) Brenan), aroeira (Myracrodruon urundeuva Allemão) e sabiá (Mimosa caesalpiniaefolia Benth). Foi realizado para cada uma dessas espécies, um experimento em Delineamento de Blocos Casualizados, constituído por 5 substratos (S1: 70% solo + 30% esterco bovino + 0% lodo de ETA; S2: 65% solo + 25% esterco bovino + 10% lodo de ETA; S3: 60% solo + 20% esterco bovino + 20% lodo de ETA; S4: 55% solo + 15% esterco bovino + 30% lodo de ETA e S5: 50% solo + 10% esterco bovino + 40% lodo de ETA) e 4 repetições. As características avaliadas foram: Emergência (E), Diâmetro do Coleto (DC), Altura da Parte Aérea (H), Comprimento da Raiz Principal (CRP), Massa Seca da Parte Aérea (MSPA), Massa Seca das Raízes (MSR), Massa Seca Total (MST), Relação Altura da Parte Aérea/Diâmetro do Coleto (H/DC), Relação Massa Seca da Parte Aérea/Massa Seca das Raízes (MSPA/MSR) e Índice de Qualidade de Dickson (IQD). Constatou-se para mudas de angico, resultados superiores de DC, H, MSPA, MST e H/DC, quando utilizou-se os substratos 2, 3, 4 e 5, enquanto nas demais variáveis observou-se resultados semelhantes. Nas mudas de aroeira, verificou-se resultados superiores de DC ao utilizar os substratos 3, 4 e 5, sendo semelhante as demais características estudadas. Já em relação às mudas de sabiá, não houve influência dos substratos em nenhuma variável. O lodo da Estação de Tratamento de Água estudado pode ser utilizado na composição do substrato, compondo até 40%, para produção de mudas de angico, aroeira e sabiá.

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