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1.
J Environ Biol ; 31(3): 369-73, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-21047013

RESUMEN

Fire is an important tool in the management of forest ecosystems. Although both prescribed and wildland fires are common in Turkey, few studies have addressed the influence of such disturbances on soil properties and root biomass dynamics. In this study, soil properties and root biomass responses to prescribed fire were investigated in 25-year-old corsican pine (Pinus nigra Arn.) stands in Kastamonu, Turkey. The stands were established by planting and were subjected to prescribed burning in July 2003. Soil respiration rates were determined every two months using soda-lime method over a two-year period. Fine (0-2 mm diameter) and small root (2-5 mm diameter) biomass were sampled approximately bimonthly using sequential coring method. Mean daily soil respiration ranged from 0.65 to 2.19 g Cm(-2) d(-1) among all sites. Soil respiration rates were significantly higher in burned sites than in controls. Soil respiration rates were correlated significantly with soil moisture and soil temperature. Fine root biomass was significantly lower in burned sites than in control sites. Mean fine root biomass values were 4940 kg ha(-1) for burned and 5450 kg ha(-1) for control sites. Soil pH was significantly higher in burned sites than in control sites in 15-35 cm soil depth. Soil organic matter content did not differ significantly between control and burned sites. Our results indicate that, depending on site conditions, fire could be used successfully as a tool in the management of forest stands in the study area.


Asunto(s)
Biomasa , Incendios , Pinus , Raíces de Plantas , Suelo/análisis , Respiración de la Célula , Concentración de Iones de Hidrógeno , Compuestos Orgánicos/análisis
2.
J Environ Biol ; 31(1-2): 15-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20648810

RESUMEN

In this study soil properties and root biomass responses to prescribed fire were investigated in 25-30 year-old calabrian pine (Pinus brutia Ten.) stands in Edirne, Turkey. The stands were established by planting and were subjected to prescribed burning in July 2005. Soil respiration rates were determined every two months using the soda-lime method over a two-year period. Fine (> or = 2 mm diameter) and small root (> 2-5 mm diameter) biomass were sampled approximately bimonthly using the sequential coring method. Soil respiration rates in burned sites were significantly higher than in control sites during the summer season but there was no significant difference in the other seasons. Soil respiration rates were correlated significantly with soil moisture and soil temperature. Fine and small root biomass were significantly lower in burned sites than in control sites. Mean fine root biomass values were 3204 kg ha(-1) for burned and 3772 kg ha(-1) for control sites. Annual soil CO2 releases totaled 515 g Cm(-2) for burned and 418 g C m(-2) for control sites. Our results indicate that, depending on site conditions, fire could be used successfully as a tool in the management of calabrian pine stands in the study area.


Asunto(s)
Incendios , Consumo de Oxígeno , Pinus/fisiología , Raíces de Plantas/fisiología , Microbiología del Suelo , Ecosistema , Factores de Tiempo , Turquía
3.
Environ Monit Assess ; 151(1-4): 93-104, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18496760

RESUMEN

Aforestation activities, silvicultural prescription, forest management decisions and land use planning are based on site information to develop appropriate actions for implementation. Forest site classification has been one of the major problems of Turkish forestry for long time. Both direct and indirect methods can be used to determine forest site productivity. Indirect methods are usually reserved for practical applications as they are relatively simple, yet provide less accurate site estimation. However, direct method is highly time-demanding, expensive and hard to conduct, necessitating the use of information technologies such as Geographic Information Systems (GIS) and Remote Sensing (RS). This study, first of all, generated a forest site map using both direct and indirect methods based on ground measurements in 567.2 ha sample area. Then, supervised classification was conducted on Landsat 7 ETM image using forest site map generated from direct method as ground measurements to generate site map. The classification resulted in moist site of 262.5 ha, very moist site of 122.5 ha and highly moist site of 191.2 ha in direct method; sites I-II cover 38.9 ha, III 289.6 ha, IV-V 143.5 ha and treeless-degraded areas of 104.2 ha in indirect method; moist site of 203.5 ha, very moist site of 232.1 ha and highly moist site of 140.6 ha in remote sensing method. However, 104.2 ha treeless and degraded areas were not determined by indirect method, yet by the other methods. Secondly, forest site map for the whole area (5,980.8 ha) was generated based on the site map generated by the direct method for sampled area. The Landsat 7 ETM image was classified based on the forest site map of sample area. The site index (SI) map for the whole area was generated using conventional inventory measurements. The classification resulted in sites I-II cover 134.1 ha, III 1,643.6 ha, IV-V 1,396.5 ha, treeless-degraded areas of 1,097.3 ha and settlement-agriculture areas of 1,709.3 ha in indirect method; moist site of 1,674.3 ha, very moist site of 853.6 ha, highly moist site of 1,729.6 ha and settlement-agriculture areas 1,723.3 ha in remote sensing method. Again the treeless- degraded areas of 1,097.3 ha were not determined by indirect method but by remote sensing method.


Asunto(s)
Monitoreo del Ambiente/métodos , Sistemas de Información Geográfica , Comunicaciones por Satélite , Árboles , Conservación de los Recursos Naturales , Ecosistema , Humanos , Árboles/clasificación , Turquía
4.
Environ Monit Assess ; 137(1-3): 149-61, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17564804

RESUMEN

The productivity of forest sites has been indirectly determined with solo wood production objective in forest management. Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes; dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate anamorphic site index (SI) equations and three site index classes; good (SI=I-II), medium (SI=III) and low (SI=IV-V) were determined. Some important differences between the methods were realized. The forest sites determined with site index estimation method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest sites of open and degraded areas should be determined according to direct method.


Asunto(s)
Monitoreo del Ambiente/métodos , Sistemas de Información Geográfica , Árboles/clasificación , Ecosistema , Estudios de Casos Organizacionales , Turquía
5.
J Environ Biol ; 26(2): 179-85, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16161970

RESUMEN

In this study, some heavy metal concentrations (Pb, Zn, Fe, Cr, Cu), suspended sediment, chemical oxygen demand (COD), biological oxygen demand (BOD), cyanide, phenol, fecal coliform and total coliform water parameters were determined in the streams (Kucuk Melen, Asarsuyu, Ugursuyu, Buyuk Melen and Aksu) of Buyuk Melen Watershed that provides drinking water to Istanbul in Western Black Sea Region of Turkey. Measurements of water quality parameters were done monthly in eleven separate stations (4 in Kucuk Melen Stream, 1 in Asarsuyu Stream, 1 in Ugur Stream, 1 in Aksu Stream and 4 in Buyuk Melen Stream) from August 2001 to August 2002. The seasonal changes in water quality parameters were evaluated statistically. The results, the parameters, COD, BOD, Pb, Zn, Fe, Cr, Cu, cyanide, fecal coliform, total coliform and suspended sediment showed significant differences among seasons and streams (ANOVA; P <0.05). According to Turkish Standarts (TS) 266, European Union (EU) and World Health Organization (WHO) criteria, the maximum values of each parameter in streams within the Buyuk Melen watershed are recorded and evaluated in this study.


Asunto(s)
Cianuros/análisis , Metales Pesados/análisis , Fenol/análisis , Microbiología del Agua , Contaminantes Químicos del Agua/análisis , Recuento de Colonia Microbiana , Enterobacteriaceae/aislamiento & purificación , Monitoreo del Ambiente , Oxígeno/análisis , Ríos/química , Ríos/microbiología , Estaciones del Año , Turquía
6.
J Environ Biol ; 25(2): 125-34, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15529867

RESUMEN

Deltas, as macro and micro biological systems at high productive levels, are the natural reserve areas of the world. Those in Turkey present the international importance landscapes as to the various ecosystem characteristics and land use patterns. Nevertheless, these areas are currently facing many problems such as biodiversity loss and environmental degradation owing to coastal settlements and pollution factors. This paper describes the factors responsible for the main features and degradation types of the Deltaic landscapes and their impact for future land use. It also deals with : an overview of the Kizilirmak Delta, one of the most important Deltas along the central part of Black Sea Region (Turkey); presents major ecosystem of it; identifies land use pattern and discusses the threats by environmental and human induced disturbances. The most considering feature of this Delta is to show the largest and most significant wetland area of Turkey which has been able to protect its natural beauties on the Black Sea Coasts. A Delta plain of 56000 hectares extends through the area at the north of the Samsun-Sinop highway. The ecological system of the Delta is extremely rich in terms of its biological variety as well as its fauna (especially number of bird species). But, the Delta including terrestrial areas close to the water resources and the vegetation between aquatic and terrestrial systems, has been constantly modified by human activities. Consequently, some considerations for environmental conservation and sustainable management were put forward for the future generations.


Asunto(s)
Conservación de los Recursos Naturales , Planificación Ambiental , Abastecimiento de Agua , Ecosistema , Humanos , Plantas , Ríos , Turquía
7.
J Environ Biol ; 24(4): 415-22, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15248656

RESUMEN

The Degirmendere and Galyan (Degirmendere tributary) Rivers that discharge their water into the Black Sea are important watersheds in the northeastern part of Turkey. Water quality parameters were sampled from 1997 through 2001 for each year at five sites (three for Galyan, two for Degirmendere) along 29 and 42 km gradients, respectively covering all seasons. Surface water was collected from the sites and analyzed for temperature, total alkaline (MAAL), total dissolved solids (TDS), dissolved oxygen (DO), pH, conductivity (EC), nitrate (NO3), nitrite (NO2), total hardness (TH), phenolphthalein alkalinities (PAL) and organic matter (PV). Seasonal changes of water quality were analyzed statistically for both Rivers and evaluated according to the TS 266, EU and WHO standards. The analysis of variance results showed that Ca, Mg, MAL, NO3, pH, TDS and TH parameters of the Degirmendere River and Ca, DO, EC, MAL, NO3, pH and TH parameters of the Galyan River showed seasonal differences (p<0.05). The maximum values of the water pollution parameters for the two Rivers were below the threshold values throughout the study period. When both Rivers were compared, the mean values of the pollution parameters of the Degirmendere River were higher than those of the Galyan River and very close the limits. The results indicate that both Rivers can be used for the production of potable water during all seasons but only with an advanced treatment in the Degirmendere and a moderate treatment in the Galyan River, and for indirect and non-contact recreational activities.


Asunto(s)
Monitoreo del Ambiente/estadística & datos numéricos , Ríos/química , Estaciones del Año , Contaminación del Agua/análisis , Análisis de Varianza , Conductividad Eléctrica , Concentración de Iones de Hidrógeno , Oxígeno/análisis , Temperatura , Turquía
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