Light spectra distributions were measured in two different montane forests: temperate and tropical. Spectral light measurements were made in different sized canopy gaps in the conifer forest at H. J. Andrews Experimental Forest in Oregon, USA. Researchers at Oregon State University created these gaps of 20 m, 30 m, and 50 m in diameter. In the tropical cloud forest, spectral light measurements were made in two plots that were permanently established at La Mucuy Parque Nacional in Venezuela, in collaboration with researchers at Universidad de Los Andes. In both studies, spectra and distributions of physiologically active light were analyzed: red, far-red, R/FR ratio, and blue light.

This study was conducted at the Ailao Mountain National Natural Reserve (NNR) in natural vegetation described as: Lithocarpus xylocarpus/Castanopsis wattii (Oak /Chestnut association) forest. Study sites were located in the Xujiaba area of the reserve at an altitude of ~ 2450 m with slopes of 10-15 degrees. This type of forest is believed to be unique to the NEAR area. The forest is floristically characterized by multiple families and genera. It has two tall tree layers, a well-developed bamboo (Sinarundinaria nitida) layer and evergreen fern species. Bryophyte, ferns and lichen occur and abundant epiphytic bryophyte is present on tree boles.A number of important aspects of nutrient cycling, including patterns of biomass and nutrient accumulation; nutrient return in litterfall and release from decomposing leaf litter; annual nutrient uptake and retention, and nutrient input and output budgets through hydrological flux in natural Lithocarpus/Castanopsis forest in the reserve, were investigated.This natural forest is characterized by high biomass accumulation of living and dead materials. Trees account for >90 % of total biomass. Dead wood comprises a high proportion (9-41 %) of total stand biomass. The sequence of inorganic nutrient element content decreased in the order leave s>b ranche s>roots> stems. Elemental content of the total stand decreased in the order of C>Ca>N>K>AI>Mg>P>Fe>Mn. The elements C, Ca and N were mainly in stems while AI and Fe were mainly in roots.Litterfall was sampled using traps during the period 1991-1999. High variations in litter production between years were associated with masting years of canopy species, and exceptional physical events (strong winds and snow). The mean annual litterfall is 7.12 t ha-1 with a bimodal seasonal pattern in litterfall: the main litterfall peak occurred in April-May and a lesser one in October-November. Woody ++ / litter and reproductive parts contribute relatively high proportions in this natural forest compared with other montane forests. Woody litter had low N and P concentrations compared with the leaf and reproductive parts. Elements return to the soil through small litterfall decreases in the order C>N>Ca>K>Mg>Mn>AI>P>Fe.The standard litter-bag technique was used to determine decomposition of leaf litter from three dominant canopy species (L. xylocarpus, L. chintungensis, C. wattii), one dominant understory species (the bamboo S. nitida) and a mixture of dominant bryophytes between Nov. 1997 and Oct. 1999. In each case, fast initial litter decomposition was followed by lower rates. Decomposition rates of canopy species and bamboo leaf litter appear to be controlled by initial concentration of lignin, N and P more than by morphological features of the leaves. P seemed to limit decomposition of all leaf litter, both initially and later. Nutrient release from decomposing leaf litter is in the order of K>Mg>Ca>N>P>~Fe, except for bamboo (S. nitida) K>Ca> P>N>Mg>Mn>Fe.Nutrient fluxes in bulk precipitation, throughfall and stemflow were measured in the natural forest between Jan. 1998 and Dec. 1999. This forest exhibited low interception by the canopy (13 % of total rainfall). N, P, Ca and S annual throughfall inputs were mainly from precipitation, while most of the K and two thirds of the Mg throughfall input was due to canopy leaching. There were significant effects of epiphytes on the amount and chemical composition of stemflow. Water volume and annual amounts of N, Ca and Mg were reduced, while K, P and S 1 were increased in stemflow after removing epiphytes on boles and branches.Plot- and catchment level approaches were applied to determine nutrient output from the ecosystem during the study period. The results indicated that this catchment has a subsurface flow system. ++ / The amounts of percolation water varied with soil depths. Concentrations of all nutrient elements studied were greater in surface water than in soil solution and stream water. The budgets for all nutrient elements between atmospheric inputs and outputs by both seepage and stream flow were positive, except for calcium (negative).This forest appears to be characterized by relatively high nutrient return (5.6-8.0 % of the total storage) and low nutrient retention (2.0-2.7 % of the total storage). The relative rate of nutrient cycling occupies an intermediate position between temperate evergreen broad-leaved forest and tropical montane rain forest, it is closer to montane rain forests in rates of nutrient circulation.

This study developed a heirarchical approach to improve the efficiency and reliability of surveys for stream-breeding frogs in the montane forests of south-eastern Australia. Areas with suitable climate for some of these species were first determined by bioclimatic modelling. Landscape and habitat preferences were then determined for the four species commonly found in far East Gippsland, along with an assessment of survey techniques from which effective survey protocols were developed. The climate of localities at which five stream-breeding species had been previously found was modelled using BIOCLIM, and maps of the predicted potential distributions having similar climate were developed. Litoria phyllochroa was found to occur in coastal to alpine areas from Melbourne to Nowra, and potentially further inland, in areas with relatively low temperatures and low summer rainfall. Litoria lesueuri had a slightly larger known and predicted distribution, covering a wide range of values for the temperature and precipitation parameters. Both species had predicted areas inland from Melbourne and the Blue Mountains where they had never been recorded, probably largely due to land clearing. The rare Heleioporus australiacus had a slightly more northerly distribution, closer to the coast and adjacent ranges from Central Gippsland to just north of Sydney, with a generally warmer climate and large range of average annual precipitation values. Litoria citropa occupies an even narrower area along the coast, extending slightly further north again, with a climatic profile of few extremes but with relatively high rainfall particularly in summer. The rare Mixophyes balbus had a more northerly known and predicted narrow range along the NSW coast, just extending into Victoria and Queensland, characterised by the subtropical influence of higher summer rainfall. The southern extension into far East Gippsland appears to have an extreme sub-climate, and is hence considered highly susceptible to climate change. Future monitoring sites for these species can now be systematically chosen to include their full climatic range, so that any negative effects of climate change on amphibian populations may have a greater chance of detection. Four species were found commonly enough in the far East Gippsland study area for more detailed study - the three stream-breeding specialist species, L. phyllochroa, L citropa, and L. lesueuri, along with Crinia signifera which was not restricted to streams but commonly found along them. Three species, L. phyllochroa, L citropa and L. lesueuri, were not found at the few higher altitudes sites on the Errinundra Plateau, however they may have been restricted by habitat requirements other than altitude. Litoria phyllochroa was otherwise widespread, but preferred larger in-stream pools and backwaters for breeding with overhanging vegetation for perch and call sites. The other three species preferred stream reaches characterised by wide bedrock outcrops and associated wide break in the tree canopy, which may allow their preferred perch sites on rocky substrates to retain heat after sunset. Litoria lesueuri tadpoles were found in both unconnected and connected pools, and the common association of this species with bedrock outcrops may explain its range being largely restricted to granitic substratum where these outcrops mostly occurred. Litoria citropa preferred reaches with bedrock and boulder outcrops, although frogs used both rocky and vegetative substrates as perch sites, with tadpoles caught in both unconnected pools and backwaters. Crinia signifera tadpoles were mostly restricted to unconnected pools, with frogs generally only detected within or very close beside these. Habitat models varied in their predictive ability, from 67.5% for L. phyllochroa frogs to 92.7% for L. lesueuri tadpoles. Models developed from normally-distributed habitat variables by discriminant function analysis were generally more predictive than those from logistic regression analysis. The occurrence of frogs and tadpoles of L. phyllochroa, L. citropa and L. lesueuri can be predicted by the measurement of five habitat variables along a 50m reach: average width between the banks, average channel width, an average of the maximum depth of channel cross-sections along the reach, channel slope, and proportion of the stream length as pools. The occurrence of C. signifera along reaches can be predicted with the additional measurement of the proportion of the banks covered in ferns, the maximum cross-sectional channel depth along the reach, and the number of unconnected pools. Several different techniques for surveying frogs were compared for the four species commonly found along the streams. Probability of detection models were derived for each species for each technique, which allowed calculation of the statistical confidence of detecting a species that actually occurred at a site for any given number of surveys. For transect-based techniques, models were also developed which allowed determination of the minimum number of surveys required without detecting a species to be 95 percent statistically confident that the species did not occur there, for various transect lengths. This level of confidence can be obtained for the four common species by four surveys using the reliable night encounter technique along 500m stream transects, during the period from Ocotber to March, with air temperatures above 10°C. The application of habitat models to select favourable 50m reaches for survey also generally improved the detectability of each species. Timer-activated tape recorders, which automatically recorded the calls of frogs for many consecutive nights at a site, were very efficient at detecting all species except the quietcalling L. lesueuri. Night encounter surveys along stream transects detected all species from a reasonable effort, and dip-netting for tadpoles was also effective for most species. Active visual encounter surveys were less reliable, and day encounter surveys detected few frogs but provided some additional data when other activities were being performed along the streams. The findings of this study have important implications for future amphibian surveys and monitoring undertaken in East Gippsland and the south coast of New South Wales. If the standardised survey techniques recommended by this study are used in Environmental Impact Assessments, their results can be objectively assessed and defended. The use of habitat modelling and improvement in survey reliability can also be used more efficiently to find sites with populations suitable for monitoring. The likely amount of effort required by a long-term monitoring program can also be determined so as to largely overcome daily variations in the detection of each species.

This project was aimed at investigating behaviour and condition of the Yellow-breasted Boubou, Laniarius atroflavus, in response to habitat differences across core, edge and riparian Afro-montane forest habitats at the Ngel Nyaki Forest Reserve, Nigeria. This species is little known and conservation effort will require direction in identifying the habitat of best quality for their survival. The determination of habitat association using correspondence analysis of census data suggested strongest association with the riparian habitat, even though this habitat held the least overall avian biodiversity as determined from a modified Shannon index. L. atroflavus appeared not to hold territories in the core habitat. Territoriality, vocalisation and time budget showed trends indicating L. atroflavus were more abundant and fared better in the riparian habitat. In this habitat, there was a greater density of territories and a smaller mean territory size, better call quality in frequency bandwidth and duration, and increased displaying and foraging time in the riparian habitat. Difference in size, colour and growth-based measures of condition showed difference between sexes, but did not show a strong habitat effect – males were larger than females, yet females appeared to have better quality of yellow breast feathers for equal carotenoid concentration. The effect of nest predation risk as a predictor of habitat quality revealed nests in the riparian habitat had the greatest daily survival probability, and within this habitat nests established at lower heights survived longest. While the evidence pointed towards the riparian habitat being most suitable for L. atroflavus, this habitat sadly continues to suffer anthropogenic disturbance and this species’ IUCN listing as Least Concern was suspected be an over-estimation.

The tropical montane forest of Ecuador is one of the ‘hot spots’ of species diversity. Despite this great species diversity, there are forests in our study area, namely in the Zamora-Chinchipe province in southern Ecuador, which are being depleted at an alarming rate. For example, large areas are being permanently deforested for use as ‘pastureland ’. This development is typically characterized by intensive slash and burn activities for vegetation clearance. After clear cut and slash burning, pasture species are planted of which Setaria sphacelata and Melinis minutiflora, are the most common. However, forest clearing by slash burn for pasture production occurs in the region simultaneously with subsequent invasion of bracken fern (Pteridium arachnoideum) and re-colonization of secondary succession vegetation on abandoned pasture land. In this study, we will examine the effects that the above phenomena have on ecosystems, namely the effects associated with the conversion of natural forestland to pasture land, and the succession that occurs as a result. We will also examine how land use change affects the nutrient status of the soil. This study focuses specifically on the area called the ‘San Francisco Valley’, (3°58’ 30”S latitude, 79°4’ 25”W longitude), which lies between Loja and the Zamora-Chinchipe provinces in Ecuador. Field work for this study was carried out at 1,798 and 2,226 m a.s.l in the following sites: 1) the San Francisco Natural Forest (this area refers to the eastern part of Podocarpus National Park); 2) active pastures Type I (this area refers to the pastureland in front of the San Francisco Scientific Station ECSF, and are pastures that have existed for 50 years or more); 3) active pastures Type II (this area refers to the pastureland in Sabanilla sites, and are pastures that have existed for approximately 17 years); and 4) abandoned pastureland (affected by succession over a period of at least twenty years). Each land-use type consists of five plots of approximately 20 x 20m2. Five points in each plot were then chosen and later sampled (two sub-samples) according to the defined horizons and depth units, namely the organic layer and mineral top soil horizons. Organic layer (only on forest and succession sampling plots) were designated as LOf1, Of2/Oh1 and mineral top soil was sampled to a depth of a 0-10, 10-20, 20-30 cm. To quantify the effects of the impact that land use change has on the chemical characteristics of soil in the selected areas, we analyzed the following bio-elements: the pH value, soil organic carbon (SOC), the total nitrogen (TN), the effective cation exchange capacity (ECEC), as well as stocks of total and available macronutrients. In addition, we examined the biological characteristics such as carbon and nitrogen microbial biomass (MBC, MBN), basal respiration (BR), and nitrogen mineralization (Nmin) in organic layers and top mineral soils (0-30 cm) of the following: the San Francisco Natural Forest, ECSF pastureland, Sabanilla pastureland, and abandoned pastures affected by succession. The main results of this study can be summarised as follows: The soil pH value increased after forest-to-pasture conversion and tended to decrease with soil depth. Moreover, pastureland in the study that was fifty years or more, showed evidence of a decrease in pH values. This decrease in pH value of the soil can be attributed to the reduction in exchangeable cations . However, they still remained higher than the pH values for the forest sites in the study. After the abandonment of pastureland, we observed a re-acidification in the soil of succession sites. This resulted in a decrease of base saturation . On the other hand, the total exchangeable base cation stocks were significantly higher for pasture soils compared with forest and succession soils. This was because of the addition of basic cations by ‘slash and burn activity ’. In this study, we observed that the greater values of soil organic carbon stocks occurred in forest sites. This can be explained by their high SOC value in the organic layer (73.9 Mg ha-1). However, the mineral layer (0 to 30 cm depth) of forest had a lower value than pasture and succession sites. This higher SOC stock of the mineral layer of our pasture sites are partly a result of carbon input from the former standing biomass. Likewise, in the mineral layers, we found that MBC content increases in a similar way to the SOC content. For example, when we compared the MBC content of forests with the pasture sites, we observed that pastures had approximately three times as much MBC. The results of nitrogen stored in the Microbial Biomass (MBN) showed the same tendency as the MBC values. Moreover, for organic layers, the total nitrogen stocks of forest were higher compared to succession sites. On the other hand, for mineral soil (0 to 30 cm depth), nitrogen stocks increased after forest to pasture conversion. This increase is partly due to the burning of aboveground biomass and the subsequent death of roots. Furthermore, the values of nitrogen stocks decreased again in succession sites (4.2 Mg N. ha-1), with similar values those of forests (4.4 Mg N. ha-1 ). Our results show that the slash-and-burn practice leads to a significant increase of P stock. We found that stocks of total phosphorus were significantly higher in the mineral topsoil (0–30 cm) of 50 year-old pastures (ECSF) than in the 17 year-old pastures (Sabanilla). It is important to note that the P stocks in the mineral soil of the abandoned pasture (20 year-old pasture sites) tend to return to forest values (399.9. Kg.ha-1). Nevertheless, the results show very low values of available P on both pastures and succession sites compared with forest sites. In the organic layers, our results show significant differences in the values of basal respiration between forest and succession sites. This indicates that the level of CO2 was greater in the selected forestland due to an increase of organic material. This essentially means that there was an increase of micro-organisms in the soil and subsequently an improved nutrient cycle . For the mineral soil, however, the results only showed a significant difference of 0-10 cm depth in the ECSF pastures and forests. In our study, we did not find any significant differences in the net nitrogen mineralization values in the four studied areas. Nevertheless, the results show that net nitrogen mineralization values decrease systematically according to the depth of the land uses. Summarizing, after the conversion of forest to pasture, there was an increase of the value of bio-elements in the mineral layers at both pasture sites. However, this increase was higher in 50 year old pastures (ECSF) than in the 17 year old pastures (Sabanilla). In addition, we noticed that after 20 years of the abandonment of pastures, most measured soil properties returned to the old-growth forest levels. / El bosque montano tropical de Ecuador es uno de los \"puntos calientes\" de diversidad de especies. Pero el bosque primario en el área de investigación (la provincia de Zamora Chinchipe al Sur de Ecuador) se está perdiendo a un ritmo alarmante. Grandes áreas están siendo permanentemente deforestadas para su uso como tierras de pastoreo. Este proceso se caracteriza por el uso intensivo de fuego para desmonte de la vegetación. Después de la quema y roza, se plantan especies de pastos entre las que Setaria sphacelata y Melinis minutiflora son las más comunes. Sin embargo, la quema y tala del bosque para la conversión a zonas de pastos ocurre simultáneamente con la subsecuente invasión del helecho común (Pteridium arachnoideum), produciéndose. La difusión de esta maleza y la decreciente productividad de los pastos (especialmente Setaria spacelata y Melinis minutiflora) conducen a que las tierras se utilizan en pastoreo hasta que la tierra se agota de nutrientes y luego se abandonan. En este estudio, se examinan los efectos que los fenómenos anteriormente mencionados tienen sobre los ecosistemas; a saber, los efectos asociados a la conversión de bosques naturales en tierras de pastoreo y la posterior sucesión de los pastizales; además de cómo el cambio de uso del suelo afecta el estado nutricional de los suelos del sur del Ecuador. El estudio se sitúa en la zona del valle de San Francisco (3°58’ 30”S latitud, 79°4’ 25”W longitud), entre Loja y Zamora Chinchipe, provincias que se encuentran en el sur de Ecuador. El trabajo de campo se llevó a cabo a una altura entre 1,798 y 2,226 m s.n.m.; en: 1) las áreas de bosque natural San Francisco (esta área se refiere a la parte oriental del Parque Nacional Podocarpus); 2) pasto activos Tipo I (esta área se refiere a los pastos en frente de la Estación Científica San Francisco ECSF, y son pastizales que tienen más de 50 años de edad); 3) pastos activos Tipo II (esta área se refiere a los pastos en los sitios de Sabanilla, y son pastizales que existen desde hace aproximadamente 17 años); y 4) pastos abandonados bajo vegetación de sucesión (más de 20 años de edad). Cada tipo de uso de la tierra consistió en cinco parcelas de aproximadamente 20 x 20 m2; se eligieron cinco puntos en cada parcela y se tomaron muestras (dos sub-muestras) de acuerdo con los horizontes orgánico y mineral. Las capas Orgánicas (solo presentes en el bosque y en los sitios de sucesión) se identificaron como LOf1, Of2/Oh1 y las capas minerales se muestrearon hasta los 0-30 cm de profundidad del suelo. Para cuantificar los efectos del impacto del cambio del uso de la tierra en las características químicas del suelo, se analizó los siguientes bio-elementos: pH, carbono orgánico del suelo (COS), nitrógeno total (Nt), la capacidad de intercambio catiónico efectiva (CICE), así como las reservas del contenido total y disponibilidad de los macro nutrientes. Además, las características biológicas, tales como el carbón (MBC) y nitrógeno (MBN) de la biomasa microbiana, la respiración basal (Rb) y la mineralización de nitrógeno (Nmin) en las capas orgánicas y en la capa mineral del suelo (hasta -30 cm) de los bosques naturales, pastos y pastizales abandonados bajo vegetación de sucesión. Los principales resultados del estudio se describen a continuación: El valor de pH del suelo indica una elevada acidez, después de la conversión de bosque a pastos y tiene una tendencia general a disminuir con la profundidad del suelo, cuando los pastos se hacen más viejos (más de 50 años de edad); los valores de pH del suelo disminuye como consecuencia de la lixiviación de cationes intercambiables, pero siguen siendo superiores a los valores de pH de los sitios del bosque. Tras el abandono de los pastos se observó una re-acidificación en el suelo de los sitios de sucesión, lo que resulta en una disminución de la saturación de bases. Los resultados además indican que las capas orgánicas, especialmente en los suelos de los bosques, almacenan una cantidad importante de potasio, calcio y magnesio. Sin embargo, las reservas totales de cationes básicos intercambiables fueron significativamente mayores en los suelos de los pastizales que en los bosques y que los suelos de sucesión, debido a la adición de cationes básicos producidos por la tala y quema usada en la conversión de bosques a pastizales. En este estudio, se encontró que los mayores valores de reservas de COS se producen en zonas forestales, que se corresponde con un alto valor en la capa orgánica (73,9 Mg C ha-1). Sin embargo, la capa mineral (hasta - 30 cm de profundidad) de los suelos del bosque tiene un valor menor en comparación con los valores de los pastos y sucesión. Este alto contenido de COS en los pastos, se debe en parte al ingreso de carbono desde la biomasa. Asimismo, en las capas minerales, se encontró que el contenido de carbono en biomasa microbiana (CBM) aumenta de una manera similar al contenido de carbono orgánico del suelo (COS). Por ejemplo, cuando comparamos el contenido de CBM de los bosques con los sitios de pastoreo, se observó que los pastos tenían aproximadamente tres veces más MBC. El resultado de nitrógeno almacenado en la biomasa microbiana (NBM) mostró la misma tendencia que los valores de CBM. En las capas orgánicas, las reservas totales de nitrógeno de los bosques fueron mayores en comparación con los sitios de sucesión. Por otro lado, en el suelo mineral (hasta -30 cm de profundidad) las reservas de nitrógeno aumentan después de la conversión de bosques a pastizales. Este incremento es parte debido a la quema de la biomasa superior y de la subsecuente muerte de las raíces. Además, los valores de las reservas de nitrógeno disminuyen de nuevo en los sitios de sucesión (4.2 Mg N. ha-1), a valores similares a las del bosque (4.4 Mg N. ha-1 ). Nuestros resultados muestran que las prácticas de quema y tala incrementan significativamente las reservas de fosforo, encontramos que las reservas de fosforo total fueron significativamente altas en las capas minerales (- 30 cm) de los pastos de 50 años (ECSF), seguido de los pastos de 17 años de edad (Sabanilla). Es importante notar que las reservas de fosforo en las capas minerales de los suelos de pastos abandonados (20 años de edad) tienden a retornar a los valores del bosque (399.9. Kg.ha-1). Sin embargo, los resultados muestran valores muy bajos de fosforo disponible en ambos sitios de pastos y sucesión comparado con el bosque. En las capas orgánicas, los resultados revelan diferencias significativas en los valores de la respiración basal (potencial) entre el bosque y la sucesión. Esto indica que el nivel de CO2 fue mayor en el los sitios de bosque debido a un aumento de la materia orgánica. Esto implica un aumento de los microorganismos en el suelo y, posteriormente, una mejora en el ciclo de nutrientes. En el suelo mineral, los resultados sólo muestran una diferencia significativa en la profundidad de 0-10 cm entre los pastos ECSF con los bosques. En nuestro estudio, no se encontró diferencias significativas en los valores de mineralización neta de nitrógeno entre las cuatro áreas estudiadas. Sin embargo, los resultados muestran que los valores netos de mineralización del nitrógeno disminuyen sistemáticamente con la profundidad en todos los usos de los suelos estudiados. En resumen, después de la conversión de bosques en pastizales, se produjo un incremento del valor de los bio-elementos en las capas minerales de ambos sitios de pastoreo. Sin embargo, este aumento fue mayor en los pastos de 50 años de edad (ECSF) que en los pastos de 17 años de edad (Sabanilla). Además, los resultados muestras que después de 20 años del abandono de los pastos, la mayoría de los parámetros medidos retornan a valores similares a los de los sitios de bosque. / Im globalen Kontext stellt der tropische Bergregenwald in Süd-Ecuador ein „Hotspot“ der Biodiversität dar. Im Untersuchungsgebiet ist die enorme Artenvielfalt durch die massive Zerstörung der natürlichen Waldökosysteme gefährdet. Der Wald wird durch intensive Brandrodung großflächig in Weideland umgewandelt. Im Laufe der Weidenutzung kommt es auf den Weideflächen zu einer zunehmenden Ausbreitung und Dominanz des tropischen Adlerfarns (Pteridium arachnoideum). Die Farnausbreitung und die abnehmende Produktivität der Weidegräser insbesondere von Setaria sphacelata und Melinis minutiflora, führt zum Verlassen der Weiden und zur Etablierung neuer Weideflächen durch fortgesetzte Brandrodung des Naturwaldes. Aufgelassene ehemalige Weideflächen unterliegen einer sekundären Sukzession. Innerhalb dieser Studie wurden die Effekte der Umwandlung des Naturwaldes in Weideland, der Weidenutzung sowie der Wirkungen der sekundären Sukzession nach dem Verlassen unproduktiver Weideflächen auf die Nährstoffsituation der Böden untersucht. Die Untersuchung erfolgte im Gebiet des „San Francisco Tales“, (3°58’ 30”S, 79°4’ 25”W), welches sich zwischen den beiden Provinzen Loja und Zamora-Chinchipe in Ecuador befindet. Feldarbeiten innerhalb dieser Studie wurden in einer Höhe zwischen 1798 und 2225 m NN in den folgenden Bereichen ausgeführt: 1) Naturwald in San Francisco; 2) aktive Weidefläche Typ I (seit circa 50 Jahren in Nutzung); 3) aktive Weidefläche Typ II (seit circa 17 Jahren in Nutzung); und 4) verlassenes Weideland (bestimmt durch sekundäre Sukzession seit mindestens 20 Jahren). Jeder Landnutzungstyp besteht aus fünf Plots mit einer Ausdehnung von circa 20 x 20 m. Fünf Punkte innerhalb eines jeden Plots wurden zur Beprobung ausgewählt. Die organische Auflage (Naturwald, verlassenes Weideland) wurde nach Auflagehorizonten (LOf1 und Of2/Oh) und der Mineralboden nach Tiefenstufen (0-10 cm, 10-20 und 20-30 cm) getrennt beprobt. Um die Effekte und den Einfluss des Landnutzungswandels auf chemische Bodenkennwerte zu quantifizieren, wurden die folgenden Indikatoren untersucht: pH, organischer Kohlenstoffgehalt des Bodens (SOC), Gesamtstickstoff (TN), effektive Kationenaustauschkapazität (CECeff) sowie Vorräte der gesamten und pflanzenverfügbaren Makronährelemente. Zusätzlich wurden bodenbiologische Indikatoren wie Kohlenstoff und Stickstoff der mikrobiellen Biomasse (MBC, MBN), Basalatmung (BR) und Stickstoffmineralisation (Nmin) in den organischen Auflagehorizonten und dem mineralischen Oberboden (0-30 cm) wie folgt untersucht: Naturwald in San Francisco, ECSF Weideflächen, Sabanilla Weideflächen und aufgelassene, von der Sukzession beeinflusste Weiden. Die hauptsächlichen Resultate der Untersuchung können wie folgt zusammengefasst werden: Der pH-Wert des Bodens erhöhte sich nach der Umwandlung von Wald zu Weide und zeigt mit zunehmender Tiefe einen abnehmenden Trend. Darüber hinaus nahmen die pH-Werte von der 17 Jahre alten zur 50 Jahre alten Weide ab. Diese Abnahme kann auf den Rückgang austauschbarer Kationen zurückgeführt werden. Dennoch verblieb der pH-Wert in den 50 Jahre alten Weiden oberhalb des pH-Wertes der im Wald beprobten Flächen. Nach dem Auflassen der Weiden wurde eine erneute Versauerung des Bodens im Stadium der Sukzession beobachtet. Dieser pH-Rückgang wird durch einen Abnahme der Basensättigung begleitet. Auf der anderen Seite waren die Vorräte an austauschbaren Basen der CECeff auf den Weideflächen signifikant über denen der Wald- und Sukzessionsflächen. Ursächlich dafür war die Freisetzung basischer Kationen während der Brandrodung des Naturwaldes. Innerhalb dieser Studie wurden die höchsten Vorräte an Bodenkohlenstoff im Naturwald ermittelt. Das kann durch hohe Vorräte an SOC in der organischen Auflage (73.9 Mg ha-1) erklärt werden. Allerdings waren die Vorräte im Mineralboden (0-30 cm) des Waldes geringer als auf den Weide- und Sukzessionsflächen. Diese höheren SOC-Vorräte im Mineralboden der Weideflächen sind teilweise das Resultat der höheren Kohlenstoffzufuhr durch Reste der oberirdischen Biomasse. Der Gehalt an mikrobiellem Biomassekohlenstoff nahm in ähnlicher Art und Weise wie der des bodenbürtigen organischen Kohlenstoffs zu. Beispielsweise wurde beim Vergleich von MBC und MBN-Gehalten des Waldes mit denen der Weide der dreifache Gehalt in der Weide gefunden. Außerdem waren die Stickstoffvorräte der organischen Auflagen im Wald höher als auf den Sukzessionsflächen. Andererseits nahmen die Stickstoffvorräte nach der Umwandlung von Wald zu Weide im Mineralboden (0-30 cm) zu. Diese Zunahme beruht zum Teil auf dem Abbrennen der oberirdischen Biomasse und dem anschließenden Absterben der Wurzeln. Des Weiteren verringerten sich die Stickstoffvorräte im Stadium der Sukzession (4.2 Mg N ha-1) und glichen sich wieder denen des Waldes (4.4 Mg N ha-1) an. Die Resultate zeigen, dass die Brandrodung zu einem signifikanten Anstieg der Phosphorvorräte führte. Vorräte des Gesamtphosphors waren in den mineralischen Oberböden (0-30 cm) der 50 Jahre alten Weide, gefolgt von der 17 Jahre alten Weide signifikant am höchsten. Zu betonen ist, dass die P-Vorräte im Mineralboden der aufgelassenen Weide dazu tendieren auf Werte des Waldes abzusinken (399.9 kg ha-1). Trotzdem zeigten die Ergebnisse sehr geringe Werte für pflanzenverfügbaren Phosphor in Weide und Sukzession im Vergleich zum Wald. In den organischen Auflagehorizonten wurden signifikante Unterschiede in der mikrobiellen Aktivität (Basalatmung) zwischen Wald und Weide gefunden. Das zeigt, dass das Niveau an C-Mineralisierung in der ausgewählten Waldfläche größer ist, was auf die erhöhte Verfügbarkeit der organischen Substanz zurückgeführt werden kann. Das bedeutet im Wesentlichen einen Anstieg der Mikroorganismen in den Böden und darauffolgend einen verbesserten Nährstoffkreislauf. Für den Mineralboden zeigten die Ergebnisse jedoch nur einen signifikanten Unterschied in einer Tiefe von 0-10 cm zwischen Wald und Weide. Signifikante Unterschiede in der Nettostickstoffmineralisation der vier untersuchten Gebiete konnten nicht gefunden werden. Nichtsdestotrotz zeigten die Ergebnisse, dass die Nettostickstoffmineralisation mit zunehmender Tiefe in den unterschiedlichen Landnutzungen abnimmt. Zusammenfassend kann festgestellt werden, dass nach der Brandrodung die Gehalte an Bioelementen im Mineralboden beider Weideflächen zunahmen. Dieser Anstieg war in den 50 Jahre alten Weideflächen (ECSF) sogar ausgeprägter als in den 17 Jahre alten Weideflächen (Sabanilla). Zusätzlich zeigte sich in den 20 Jahre alten Sukzessionsflächen, dass durch die Regeneration einer organischen Auflage ein positiver Effekt hinsichtlich erhöhter Vorräte an SOC und pflanzenverfügbarem Phosphor festgestellt werden konnte. Diese allmähliche Zunahme an Nährstoffen im Boden der Sukzession setzte sich fort, bis das Ausgangsniveau des Waldes wieder erreicht war.

Freie Universiẗat, Diplomarbeit u.d.T.: Piechowski, Daniel: Vegetationsstrukturanalyse unterschiedlich beeinflusster submontaner Regenwälder in Ecuador--Berlin, 2003.

Made available in DSpace on 2015-03-26T12:52:47Z (GMT). No. of bitstreams: 1 texto completo.pdf: 5729542 bytes, checksum: 5d7bd2e52fd6129fda123a027c3917dc (MD5) Previous issue date: 2011-06-30 / Protected areas (PAs) of the Caparaó and Itatiaia are in alignment with mountain pronounced northeast-southwest direction of the Serra da Mantiqueira mountains, with the National Park of Itatiaia southwest of Rio de Janeiro and the south of Minas Gerais, and National Park of Caparaó southwest of Espírito Santo and eastern Minas Gerais. These two protected areas represent high mountains ecosystems dominated by altitude fields, where they differ from their surroundings by presenting endemic pedoenvironment, water stress, nutrient content and accumulation of humified organic matter. Because of the major soil and climatic differences between these areas and their surroundings, there are particular vegetation, refuge areas considered environmentally friendly. Given the lack of research of the physical environment, the goal was to study the micromorphological features of the profiles P2 and P6 of National Park of Caparaó-MG and the physical, chemical and mineralogical soil of two toposequence in each of the alignment of National Parks in the Serra Mantiqueira mountains in the portion of Minas Gerais of the Protection Areas (PAs) of Caparaó and Itatiaia, establishing relations between pedogenesis, variations litho-structural, morphology and vegetation cover. The geological foundation of the PAs is formed by syenite (Itatiaia) and migmatized gneiss, migmatite occurrence with amphibolite dikes (Caparaó). The soil toposequence of the two, regardless of the geological matrix, the depth of the solum and vegetation type that grows on them, are poor in nutrients and have high levels of aluminum saturation. The amounts of exchangeable aluminum (exchangeable acidity) are low, even negligible in the subsurface layers. This fact indicates that the action of stable complexes of aluminum and organic matter stabilizes the organic matter and make it more resistant to microbial decomposition in the high mountains environment of Minas Gerais. Poverty chemistry of these soils is mainly due to the geological nature of the matrix dominant in these high mountains environments and, in part, to losses by leaching and erosion that the system presents. These losses are associated with prominent and very busy little thickness of the solum. In these high mountains environments litholic neo soils predominate and humic cambisols, herbaceous vegetation and undergrowth and rocky outcroppings. In two toposequence studied in the area of occurrence of scrub vegetation type and field with candles, the oligotrophic, shallow soils and more exposed position in the landscape are obstacles to the occurrence of a denser forest type. The upper montane and montane forests occupy the western part of the Minas Gerais portion of National Park of Caparaó, and the atlantic fase of Itatiaia. The dominant tree vegetation (montane forest and upper montane) is conditioned by the most effective soil depth and water availability. In PA Caparaó the upper montane forest occurs on steep slopes with deeper soils in amphitheaters, which potentiate the development of denser vegetation. These forms of amphitheaters are conditioned geotectonic by the structure of fractured rocks that form the Maciço do Caparaó meso environments, corresponding to the modeled differential dissection with the deepening of drainage. In these areas of deeper soils, even if a note apparent wealth (arboreal vegetation) predominate extremely nutrient-poor soils. The occurrence of suspended structural valleys in both PAs, morphology abaca (area of sedimentation and clogging) plays a decisive role in the formation of histosols, responsible for strong immobilization of carbon. These areas of peatland in histosols with the National Park of Caparaó are responsible for the immobilization of approximately 1120.50 megagram of carbon per hectare, and 426 megagram of carbon per ha in the National Park of Itatiaia. Despite the importance of environmental and ecotourism of high mountains scenarios of Minas Gerais (Caparaó and Itatiaia), little is known about its physiographic characteristics. / As unidades de conservação (UCs) do Caparaó e Itatiaia encontram-se no alinhamento montanhoso com direção pronunciada nordeste-sudoeste da Serra da Mantiqueira, estando o Parna Itatiaia a sudoeste do Rio de Janeiro e ao sul de Minas Gerais e o Parna Caparaó a sudoeste do Espírito Santo e leste de Minas Gerais. Estas duas UCs representam os ecossistemas altimontanos dominados pelo Campo de Altitude, onde diferem do seu entorno por apresentarem pedoambientes endêmicos, estresse hídrico, oligotrofismo e o acúmulo de matéria orgânica humificada. Em virtude das grandes diferenças edafo-climáticas entre estas áreas e seus entornos, observam-se vegetações particulares, consideradas áreas de refúgio ecológico. Diante da lacuna de estudos do meio físico, o objetivo foi estudar as características micromorfológicas dos perfis P2 e P6 do Parna Caparaó-MG e os atributos físicos, químicos e mineralógicos dos solos de duas topossequências em cada um dos Parques Nacionais no alinhamento da Serra da Mantiqueira, na porção mineira das Unidades de Conservação (UCs) do Caparaó e Itatiaia, estabelecendo as relações entre pedogênese, as variações lito-estruturais, a morfologia e a cobertura vegetal. A base geológica das UCs é formada pelo sienito (Itatiaia) e pelo gnaisse migmatizado, migmatito com ocorrência de diques de anfibolitos (Caparaó). Os solos das duas topossequências, independentemente da matriz geológica, da profundidade do solum e da fitofisionomia que sobre eles se desenvolve, são pobres em nutrientes e apresentam elevados índices de saturação por alumínio. Os valores de alumínio trocável (acidez trocável) são baixos, chegando a negligenciáveis nos horizontes subsuperficiais. Tal fato sinaliza que a ação dos complexos estáveis de alumínio e matéria orgânica estabiliza a MO e a tornam mais resistente à decomposição microbiana nos ambientes altimontanos de Minas Gerais. A pobreza química desses solos é devida principalmente à natureza da matriz geológica dominante nestes ambientes altimontanos e, em parte, às perdas por lixiviação e erosão que o sistema apresenta. Tais perdas estão associadas ao relevo muito movimentado e à pouca espessura do solum. Nestes ambientes altimontanos predominam Neossolos Litólicos e Cambissolos Húmicos, vegetação herbácea e subarbustiva e Afloramentos Rochosos. Nas duas topossequências estudadas, na área de ocorrência da tipologia vegetal, escrubes e campo com candeias, o oligotrofismo, solos mais rasos e a posição mais exposta na paisagem são obstáculos para a ocorrência de uma tipologia florestal mais densa. As Florestas Alto-Montana e Montana ocupam a porção oeste da parte mineira do Parna Caparaó, e a face atlântica do Itatiaia. A vegetação com dominância arbórea (Floresta Montana e Altomontana) está condicionada pela maior profundidade efetiva do solo e disponibilidade de água. Na UC do Caparaó a Floresta Alto-Montana ocorre em encostas íngremes com solos de maior profundidade em anfiteatros, que potencializam o desenvolvimento de cobertura vegetal mais densa. Essas formas em anfiteatros são mesoambientes condicionados pela estrutura geotectônica fraturada das rochas que formam o Maciço do Caparaó, correspondendo aos modelados de dissecação diferencial com o aprofundamento da drenagem. Nestas áreas de solos mais profundos, ainda que se observe uma riqueza aparente (porte arbóreo da vegetação) predominam solos extremamente pobres em nutrientes. A ocorrência de vales estruturais suspensos em ambas as UCs, com morfologia abaciada (área de sedimentação e colmatagem) tem papel primordial na formação dos Organossolos, responsáveis por forte imobilização de carbono. Estas áreas de turfeiras com Organossolos no Parna Caparaó são responsáveis pela imobilização de aproximadamente 1.120,50 megagramas de carbono por hectare e de 426 megagramas de carbono por ha no Parna Itatiaia. Apesar da importância ambiental e ecoturística dos cenários altimontanos de Minas Gerais (Caparaó e Itatiaia), pouco se conhece sobre suas características fisiográficas.

O trabalho foi realizado no Parque Estadual da Serra do Mar - Núcleo Santa Virginia,coordenadas geográficas são: 45 30 a 45 11 O e 23 17 a 23 24 S, com o objetivo de avaliar as diferentes respostas da comunidade de palmeiras em dois escorregamentos ocorridos no verão de 1996 devido a um evento atmosférico (Zona de Convergência do Atlântico Sul). Um dos escorregamentos situado em área de floresta preservada e o outro situado em área de vegetação secundária. Por meio de parcelas circulares de 100m2 alocadas nas bordas das cicatrizes dos escorregamentos e no interior da vegetação do entorno de cada cicatriz, em três cotas altitudinais: base, meio e alto. A comunidade de palmeiras foi representada por cinco espécies em três estádios ontogenéticos (plântulas, jovens e adultos), sendo as espécies: Attalea dúbia, Euterpe edulis, Geonoma gamiova, G. pohliana e G. schottiana. A perturbação causou alterações na comunidade de palmeiras de maneira que as espécies como Euterpe edulis e G. schottiana foram estimuladas pelo aporte de luminosidade provocado pelo deslizamento, enquanto G. gamiova diminuiu drasticamente nestas condições em todos estádios de desenvolvimento. Dentre as quais E. edulis, G. gamiova e G. schottiana apresentaram alteração na estrutura de suas populações com aumento da porcentagem de freqüência dos indivíduos jovens. O padrão de regeneração observado indica que espécies de diferentes estratos florestais respondem de modos diferentes a este tipo de perturbação, entretanto não é possível fazer generalizações para outras áreas.

Meadows are crucial components to larger river watersheds because of their unique hydrologic and ecological functions. Due to climate change, over grazing, and fire suppression, conifer encroachment into meadows has accelerated. In some western regions, nearly half of all meadow habitat has been loss due to conifer encroachment. Restoration of these hydrologic systems requires tree removal. Many studies exist that address the issue of conifer encroachment in montane meadows, however, few studies focus on the role that conifer removal plays on the encroaching meadow. Furthermore, few studies exist that document the hydrologic change from conifer removal and further restoration steps, if any, to take after the removal. The overall research goal is to understand the efficacy of removal of encroached conifers from an encroached meadow (Marian Meadow) for successful meadow restoration. The objectives of this study are to determine (i) quantify the meadow hydrology following removal of encroached conifers, (ii) determine if forest tree removal adjacent to the meadow influences the meadow’s hydrology, and (iii) test three common revegetation techniques for a formerly encroached montane meadow.. Marian Meadow is in Plumas County, CA at an elevation of 4,900 feet. This 45-acre meadow enhancement project is part of a 2,046-acre timber harvest plan implemented by the Collins Pine Company. Soil moisture sensors at one foot below the ground and water table depth sensors at four feet below ground were installed in Marian Meadow and a control meadow in September 2013, with additional soil moisture sensors at three-foot depth installed August 2015. The removal of encroaching conifers from Marian Meadow occurred in June 2015. Electrical Resistivity Tomography (ERT) was used to determine maximum water table depths and climatic variables were measured from a weather station as inputs for the water budget. A groundwater recession curve equation was used to model water table depths between water table depth sensor measurements and ERT measurements. A general linear model was used to determine any statistical significant difference in soil moisture and water table depths prior to and after conifer removal. Revegetation plots were installed at the start of the 2017 growing season to determine the establishment rate for three different techniques (BARE, WOOD, and EXISTING) and three different species of meadow plant. Technique BARE, which removes approximately 10 cm of top soil and disperses seed was statistically significant, yielding the highest population count. Another growing season data collection and control plot is required to draw further conclusions and recommendations. The water balance indicated that the majority of Marian Meadow and the Control Meadow’s water storage can be attributed to precipitation and not upland sources. This hydrologic characteristic is common in dry meadows. The statistical analysis indicated that measured water table depths increased on average by 0.62 feet following conifer removal. The first year following restoration and the second year following restoration yielded statistically significantly different water levels than pre-restoration water levels. The third year following restoration is inconclusive until the end of the 2018 WY data set is available. On average, soil moisture increased by 6.43% following conifer removal and was statistically significantly different in all three post restoration years when compared to pre-restoration volumetric soil moisture content. Additionally, growing season (April through September) water table depths indicated that meadow vegetation communities could be supported in Marian Meadow following conifer removal. The removal of conifers from an encroached meadow appears to promote soil moisture and water table depth conditions indicative of a meadow and meadow plant community types.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20586号 / 農博第2238号 / 新制||農||1052(附属図書館) / 学位論文||H29||N5075(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 神﨑 護, 教授 北島 薫, 教授 井鷺 裕司 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM