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• 1. [Article] Integrating Liana Abundance and Forest Stature into an Estimate of Total Aboveground Biomass for an Eastern Amazonian Forest

  This study provides an estimate of aboveground live biomass for an intact eastern Amazonian forest. An allometric regression biomass equation was developed to estimate the aboveground biomass of live lianas. ...

  Citation × Citation Citation Abstract Copy Title: Integrating Liana Abundance and Forest Stature into an Estimate of Total Aboveground Biomass for an Eastern Amazonian Forest Author: Gerwing, Jeffrey J., Lopes Farias, Damiao Year: 2000 This study provides an estimate of aboveground live biomass for an intact eastern Amazonian forest. An allometric regression biomass equation was developed to estimate the aboveground biomass of live lianas. This equation, together with a previously published equation for trees, was then used to estimate the contributions of lianas and trees to the total biomass of forest patches in four stature classes: gap (openings in the canopy of at least 25 m2 with the dominant vegetation < 3 m high), low (3±15 m canopy height), medium (15±25 m canopy height), and high (> 25 m canopy height). Total stand-level biomass was estimated as the weighted average of the stature classes. In 130 ha of surveyed forest, forest stature classes were found in the following proportions: gap phase 8%; low stature 31%; medium stature 44%; and high stature 17%. Total aboveground biomass was found to be three times higher in high stature forest than in low. Liana biomass, however, showed the opposite result, being three times higher in low stature forest. Stand-level aboveground live biomass was estimated at 314 t ha-1 of which 43 t ha-1 (14%) was lianas. Liana leaf area index (LAI) ranged from 1.3 m m-2 in high stature forest to 5.3 m m-2 in low stature. Abundant lianas are generally interpreted as a sign of past forest disturbance. As forests throughout the Amazon basin are increasingly disturbed through human activities, it is likely that their biomass will be underestimated if the contribution of lianas is ignored. Title: Integrating Liana Abundance and Forest Stature into an Estimate of Total Aboveground Biomass for an Eastern Amazonian Forest Author: Gerwing, Jeffrey J., Lopes Farias, Damiao Year: 2000 This study provides an estimate of aboveground live biomass for an intact eastern Amazonian forest. An allometric regression biomass equation was developed to estimate the aboveground biomass of live lianas. This equation, together with a previously published equation for trees, was then used to estimate the contributions of lianas and trees to the total biomass of forest patches in four stature classes: gap (openings in the canopy of at least 25 m2 with the dominant vegetation < 3 m high), low (3±15 m canopy height), medium (15±25 m canopy height), and high (> 25 m canopy height). Total stand-level biomass was estimated as the weighted average of the stature classes. In 130 ha of surveyed forest, forest stature classes were found in the following proportions: gap phase 8%; low stature 31%; medium stature 44%; and high stature 17%. Total aboveground biomass was found to be three times higher in high stature forest than in low. Liana biomass, however, showed the opposite result, being three times higher in low stature forest. Stand-level aboveground live biomass was estimated at 314 t ha-1 of which 43 t ha-1 (14%) was lianas. Liana leaf area index (LAI) ranged from 1.3 m m-2 in high stature forest to 5.3 m m-2 in low stature. Abundant lianas are generally interpreted as a sign of past forest disturbance. As forests throughout the Amazon basin are increasingly disturbed through human activities, it is likely that their biomass will be underestimated if the contribution of lianas is ignored. Close

• 2. [Article] Reducing Waste During Logging and Log Processing: Forest Conservation in Eastern Amazonia

  This article describes the waste associated with logging and log processing in eastern Amazonia and suggests methods for reducing both waste and forest damage as a result of logging.

  Citation × Citation Citation Abstract Copy Title: Reducing Waste During Logging and Log Processing: Forest Conservation in Eastern Amazonia Author: Gerwing, Jeffrey J., Johns, Jennifer S., Vidal, Edson Year: 1996 This article describes the waste associated with logging and log processing in eastern Amazonia and suggests methods for reducing both waste and forest damage as a result of logging. Title: Reducing Waste During Logging and Log Processing: Forest Conservation in Eastern Amazonia Author: Gerwing, Jeffrey J., Johns, Jennifer S., Vidal, Edson Year: 1996 This article describes the waste associated with logging and log processing in eastern Amazonia and suggests methods for reducing both waste and forest damage as a result of logging. Close

• 3. [Article] Acorn Foraging as a Means to Explore Human Energetics and Forge Connections to Local Forests

  Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed ...

  Citation × Citation Citation Abstract Copy Title: Acorn Foraging as a Means to Explore Human Energetics and Forge Connections to Local Forests Author: Gerwing, Jeffrey J., Lockwood, Pamela, Uhl, Christopher Year: 1999 Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed with an abundant supply of oaks nearby, perhaps other species could be substituted. The exercise is unusual in two ways. It offers a new undergraduate ecology activity, and it offers opportunities for students to relate other disciplines to their science course. In "the good old days" of higher education each discipline offered its menu of courses and expected students to make appropriate connections among the courses of their major, minor, and general education. In today's educational atmosphere of integrated curricula, linked courses, and cross-disciplinary programs, the following exercise may serve as an example of linking an ecology course with sociology, anthropology, English, and mathematics. Title: Acorn Foraging as a Means to Explore Human Energetics and Forge Connections to Local Forests Author: Gerwing, Jeffrey J., Lockwood, Pamela, Uhl, Christopher Year: 1999 Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed with an abundant supply of oaks nearby, perhaps other species could be substituted. The exercise is unusual in two ways. It offers a new undergraduate ecology activity, and it offers opportunities for students to relate other disciplines to their science course. In "the good old days" of higher education each discipline offered its menu of courses and expected students to make appropriate connections among the courses of their major, minor, and general education. In today's educational atmosphere of integrated curricula, linked courses, and cross-disciplinary programs, the following exercise may serve as an example of linking an ecology course with sociology, anthropology, English, and mathematics. Close

• 4. [Article] Manejo De Cipós Na Amazônia

  Levantamentos florestais revelam que os cipós vêm se tornando cada vez mais abundantes em toda a Amazônia, tanto em florestas intactas quanto nas afetadas por atividades humanas, como a exploração de madeira. ...

  Citation × Citation Citation Abstract Copy Title: Manejo De Cipós Na Amazônia Author: Gerwing, Jeffrey J., Vidal, Edson Year: 2005 Levantamentos florestais revelam que os cipós vêm se tornando cada vez mais abundantes em toda a Amazônia, tanto em florestas intactas quanto nas afetadas por atividades humanas, como a exploração de madeira. Nessa atividade, é recomendado o corte dos cipós ligados à árvore escolhida, para reduzir os danos às demais durante a queda. Conhecer a ecologia desse grupo de plantas e seu adequado manejo é essencial para entender as conseqüências do seu corte e para cumprir as metas de conservação da biodiversidade incluídas nos projetos de manejo de florestas tropicais. Title: Manejo De Cipós Na Amazônia Author: Gerwing, Jeffrey J., Vidal, Edson Year: 2005 Levantamentos florestais revelam que os cipós vêm se tornando cada vez mais abundantes em toda a Amazônia, tanto em florestas intactas quanto nas afetadas por atividades humanas, como a exploração de madeira. Nessa atividade, é recomendado o corte dos cipós ligados à árvore escolhida, para reduzir os danos às demais durante a queda. Conhecer a ecologia desse grupo de plantas e seu adequado manejo é essencial para entender as conseqüências do seu corte e para cumprir as metas de conservação da biodiversidade incluídas nos projetos de manejo de florestas tropicais. Close

• 5. [Article] Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon

  The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition ...

  Citation × Citation Citation Abstract Copy Title: Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon Author: Gerwing, Jeffrey J., Uhl, Christopher Year: 2002 The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition in gaps created during conventional and reduced-impact logging in a forest of the eastern Brazilian Amazon. Logging treatments were conducted in side-by-side plots. Shortly following logging, 50-m2 plots were located in the approximate centers of four single treefall and four multiple treefall gaps in each logging area. Six years following logging, there were ∼40% fewer climbing lianas in reduced-impact gaps than in conventional logging gaps. In both logging areas multiple-tree gaps had higher liana densities and a higher proportion of lianas recruiting from seed than single tree gaps, where sprouts from cut or fallen lianas were more common. The mean number of liana species encountered per plot did not differ among treatments nor was there any significant difference in species diversity (Fisher's α) between logging treatments. The results of this study suggest that pre-logging liana cutting can significantly reduce post-logging liana proliferation in gaps, with no discernible negative impact on the species diversity of regenerating lianas. Title: Pre-logging Liana Cutting Reduces Liana Regeneration in Logging Gaps in the Eastern Brazilian Amazon Author: Gerwing, Jeffrey J., Uhl, Christopher Year: 2002 The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition in gaps created during conventional and reduced-impact logging in a forest of the eastern Brazilian Amazon. Logging treatments were conducted in side-by-side plots. Shortly following logging, 50-m2 plots were located in the approximate centers of four single treefall and four multiple treefall gaps in each logging area. Six years following logging, there were ∼40% fewer climbing lianas in reduced-impact gaps than in conventional logging gaps. In both logging areas multiple-tree gaps had higher liana densities and a higher proportion of lianas recruiting from seed than single tree gaps, where sprouts from cut or fallen lianas were more common. The mean number of liana species encountered per plot did not differ among treatments nor was there any significant difference in species diversity (Fisher's α) between logging treatments. The results of this study suggest that pre-logging liana cutting can significantly reduce post-logging liana proliferation in gaps, with no discernible negative impact on the species diversity of regenerating lianas. Close

• 6. [Article] Impactos da exploração madeireira e do fogo em florestas de transição da Amazônia Legal

  A exploração de madeira e os incendios têm causado severos danos a florestas na Amazonia. Faltavam estudos sobre os impactos da exploração e do fogo em florestas de transição entre a floresta ombrófila ...

  Citation × Citation Citation Abstract Copy Title: Impactos da exploração madeireira e do fogo em florestas de transição da Amazônia Legal Author: Silva Monteiro, André Luiz, Moreira de Souza Jr., Carlos, Barreto, Paulo Gonçalves, Pantoja, Frank Leone de Sousa, Gerwing, Jeffrey J. Year: 2004 A exploração de madeira e os incendios têm causado severos danos a florestas na Amazonia. Faltavam estudos sobre os impactos da exploração e do fogo em florestas de transição entre a floresta ombrófila densa e florestas de cerrado. Neste estudo, foram quantificados os impactos de várias intensidades de exploração madeireira e fogo na estrutura e composição de florestas de transição -- em termos de densidade de árvores e de cipós, cobertura do dossel e perturbação do solo e da biomassa acima do solo -- na regiao de Claudia, Mato Grosso. O estudo foi conduzido em 12 propriedades, através de inventários de campo (transectos de 10 m x 500 m). A composição e estrutura das florestas variaram em função da intensidade da exploração e do fogo e do tempo decorrido após tais eventos. Em relação à floresta nativa, a biomassa viva acima do solo foi 15% menor na floresta explorada e queimada (cuja intensidade de extração foi de 10 m³ ha-1) e 49% menor na floresta intensamente explorada e queimada (extração de 25 m³ ha). A densidade de árvores com DAP ≥ 10 cm em cada classe de floresta degradada foi menor que na floresta nativa. Por outro lado, indivíduos pioneiros desta categoria de diâmetro alcançaram densidade máxima na floresta intensamente explorada e queimada (37 caules ha-1), comparado afloresta nativa (12 caules ha-1). A densidade total de cipós foi substancialmente maior em função da degradação da floresta: 6.115 caules ha-1 na floresta intensamente explorada e queimada contra 2.685 caules ha-1 na floresta nativa. Observou-se uma redugao de 69% da cobertura do dossel e um aumento de 39% de resíduos na floresta explorada e intensamente queimada. Finalmente, o estoque de madeira de espécies comerciais nas florestas perturbadas foi significativamente menor do que na floresta intacta. Title: Impactos da exploração madeireira e do fogo em florestas de transição da Amazônia Legal Author: Silva Monteiro, André Luiz, Moreira de Souza Jr., Carlos, Barreto, Paulo Gonçalves, Pantoja, Frank Leone de Sousa, Gerwing, Jeffrey J. Year: 2004 A exploração de madeira e os incendios têm causado severos danos a florestas na Amazonia. Faltavam estudos sobre os impactos da exploração e do fogo em florestas de transição entre a floresta ombrófila densa e florestas de cerrado. Neste estudo, foram quantificados os impactos de várias intensidades de exploração madeireira e fogo na estrutura e composição de florestas de transição -- em termos de densidade de árvores e de cipós, cobertura do dossel e perturbação do solo e da biomassa acima do solo -- na regiao de Claudia, Mato Grosso. O estudo foi conduzido em 12 propriedades, através de inventários de campo (transectos de 10 m x 500 m). A composição e estrutura das florestas variaram em função da intensidade da exploração e do fogo e do tempo decorrido após tais eventos. Em relação à floresta nativa, a biomassa viva acima do solo foi 15% menor na floresta explorada e queimada (cuja intensidade de extração foi de 10 m³ ha-1) e 49% menor na floresta intensamente explorada e queimada (extração de 25 m³ ha). A densidade de árvores com DAP ≥ 10 cm em cada classe de floresta degradada foi menor que na floresta nativa. Por outro lado, indivíduos pioneiros desta categoria de diâmetro alcançaram densidade máxima na floresta intensamente explorada e queimada (37 caules ha-1), comparado afloresta nativa (12 caules ha-1). A densidade total de cipós foi substancialmente maior em função da degradação da floresta: 6.115 caules ha-1 na floresta intensamente explorada e queimada contra 2.685 caules ha-1 na floresta nativa. Observou-se uma redugao de 69% da cobertura do dossel e um aumento de 39% de resíduos na floresta explorada e intensamente queimada. Finalmente, o estoque de madeira de espécies comerciais nas florestas perturbadas foi significativamente menor do que na floresta intacta. Close