Articles containing the keyword 'degradation'

• Doi, AFE Building, School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand E-mail: roird@aeiou.pt
• Ranamukhaarachchi, AFE Building, School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand E-mail: slr@nn.th

• Haeussler, C2 Site 81 RR#2 Monckton Rd., Smithers, B.C., Canada V0J 2N0 E-mail: skeena@bulkley.net
• Bedford, B.C. Ministry of Forests, P.O. Box 9513 Stn. Prov. Govt., Victoria, B.C., Canada, V8W 9C2 E-mail: lb@nn.ca
• Leduc, Groupe de recherche en écologie forestière interuniversitaire, Université du Québec à Montréal, CP 8888, Succursale A, Montréal, Québec, Canada, H3C 3P8 E-mail: al@nn.ca
• Bergeron, Groupe de recherche en écologie forestière interuniversitaire, Université du Québec à Montréal, CP 8888, Succursale A, Montréal, Québec, Canada, H3C 3P8 E-mail: yb@nn.ca
• Kranabetter, B.C. Ministry of Forests, Bag 5000, Smithers, B.C., Canada, V0J 2N0 E-mail: jmk@nn.ca

Land degradation is widespread and a serious threat affecting the livelihoods of 1.5 billion people worldwide of which one sixth or 250 million people reside in drylands. Globally, it is estimated that 10–20% of drylands are already degraded and about 12 million ha are degraded each year. Driven by unsustainable land use practices, adverse climatic conditions and population increase, land degradation has led to decline in provision of ecosystem services, food insecurity, social and political instability and reduction in the ecosystem’s resilience to natural climate variability. Several global initiatives have been launched to combat land degradation, including rehabilitation of degraded drylands. This review aimed at collating the current state-of-knowledge about rehabilitation of degraded drylands. It was found that the prospect of restoring degraded drylands is technically promising using a suite of passive (e.g. area exclosure, assisted natural regeneration, rotational grazing) and active (e.g. mixed-species planting, framework species, maximum diversity, and use of nurse tree) rehabilitation measures. Advances in soil reclamation using biological, chemical and physical measures have been made. Despite technical advances, the scale of rehabilitation intervention is small and lacks holistic approach. Development of process-based models that forecast outcomes of the various rehabilitation activities will be useful tools for researchers and practitioners. The concept of forest landscape restoration approach, which operates at landscape-level, could also be adopted as the overarching framework for rehabilitation of degraded dryland ecosystems. The review identified a data gap in cost-benefit analysis of rehabilitation interventions. However, the cost of rehabilitation and sustainable management of drylands is opined to be lower than the losses that accrue from inaction, depending on the degree of degradation. Thus, local communities’ participation, incorporation of traditional ecological knowledge, clear division of tasks and benefits, strengthening local institutions are crucial not only for cost-sharing, but also for the long-term success of rehabilitation activities.

• Yirdaw, Viikki Tropical Resources Institute (VITRI), Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: eshetu.yirdaw@helsinki.fi
• Tigabu, Sveriges Lantbruks Universitet (SLU), Swedish University of Agricultural Sciences, Southern Swedish Forest Research Centre, P.O. Box 49, SE-230 53, Alnarp, Sweden E-mail: Mulualem.Tigabu@slu.se
• Monge, Viikki Tropical Resources Institute (VITRI), Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: adrian.mongemonge@helsinki.fi

Detecting and monitoring forest disturbance from selective logging is necessary to develop effective strategies and polices that conserve tropical forests and mitigate climate change. We assessed the potential of using the remote sensing tool, CLASlite forest monitoring system, to detect disturbance from timber harvesting in four community forests (ejidos) of the Selva Maya on the Yucatan Peninsula, Mexico. Selective logging impacts (e.g. felling gaps, skid trails, logging roads and log landings) were mapped using GPS in the 2014 annual cutting areas (ACAs) of each ejido. We processed and analyzed two pre-harvest Landsat images (2001 and 2013) and one post-harvest image (November 2014) with the CLASlite system, producing maps of degraded, deforested and unlogged areas in each ACA. Based on reference points of disturbed (felling and skidding), deforested (log landings and roads) and unlogged areas in each ACA, we applied accuracy assessments which showed very low overall accuracies (<19.1%). Selective logging impacts, mainly from log landings and new logging road construction, were detected in only one ejido which had the highest logging intensity (7 m³ ha^–1).

• Hernández-Gómez, Facultad de Ciencias Agrícolas, Universidad Veracruzana. Circuito Gonzalo Aguirre Beltrán, Isleta, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: urielxal@gmail.com
• Cerdán, Facultad de Ciencias Agrícolas, Universidad Veracruzana. Circuito Gonzalo Aguirre Beltrán, Isleta, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: ccerdan@uv.mx
• Navarro-Martínez, El Colegio de la Frontera Sur Av. Centenario km 5.5, Col. Pacto Obrero Campesino s/n. Chetumal, Quintana Roo. C.P. 77014, Mexico E-mail: manavaster@gmail.com
• Vázquez-Luna, Facultad de Ingeniería en Sistemas de Producción Agropecuaria, Universidad Veracruzana. Carretera Costera del Golfo Km. 220, C. Agrícola y Ganadera Michapan, Acayucan, Veracruz. C.P. 96000, Mexico E-mail: divazquez@uv.mx
• Armenta-Montero, Centro de Investigaciones Tropicales (CITRO), Universidad Veracruzana. Morelos No. 44 y 46, Zona Centro, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: samaria.am@gmail.com
• Ellis, Centro de Investigaciones Tropicales (CITRO), Universidad Veracruzana. Morelos No. 44 y 46, Zona Centro, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: eellis@uv.mx

Saprotrophic wood-decaying abilities of Rigidoporus microporus (Polyporales, Basidiomycota) syn. Rigidoporus lignosus and the structural alterations induced in wood blocks of Hevea brasiliensis Muell. Arg were studied. Mass loss of wood blocks was analyzed after 3 and 6 months respectively and the patterns of decay by pathogenic and endophytic isolates of this fungus were investigated using light microscopy. Effects of temperature on growth of the isolates on malt extract agar were also investigated. The R. microporus isolated from a non-H. brasiliensis host caused the highest percentage mass loss (27.2% after 6 months), followed by isolates ED310 (21.1%) and M13 (15.7%), both collected from diseased H. brasiliensis plantations. The isolate initially identified as an endophyte showed very low saprotrophic wood decay capability (4.3% after 6 months). The optimal temperature for growth of the isolates was 30 °C; except for the endophytic isolate which showed highest growth at 25 °C. Wood samples degraded by the R. microporus isolates showed simultaneous attack of wood cell walls, typical of white rot fungi. Results of the study indicate variability in the wood degrading abilities of the isolates and the potential differences in their physiology are discussed. Our findings further support the need for a taxonomical revision of the Rigidoporus genus.

• Oghenekaro, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: abbot.oghenekaro@helsinki.fi
• Daniel, Department of Forest Products/Wood Science, Swedish University of Agricultural Sciences, P.O. Box 7008, SE-75007 Uppsala, Sweden E-mail: geoffrey.daniel@slu.se
• Asiegbu, Department of Forest Sciences, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: fred.asiegbu@helsinki.fi

• Yirdaw, Viikki Tropical Resources Institute (VITRI), Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: eshetu.yirdaw@helsinki.fi
• Kanninen, Viikki Tropical Resources Institute (VITRI), Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: markku.kanninen@helsinki.fi
• Elfadl, Viikki Tropical Resources Institute (VITRI), Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland E-mail: mohamed.elfadl@helsinki.fi
• Tsegai, UNCCD Secretariat, Platz der Vereinten Nationen 1, 53113 Bonn, Germany E-mail: dtsegai@unccd.int