Journal Article

Permanent link for this collectionhttps://hdl.handle.net/10535/5

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Biogeochemical Factors Contributing to Enhanced Carbon Storage Following Afforestation of a Semi-Arid Shrubland
(2007) Grunzweig, J. M.; Gelfand, I.; Yakir, D.
"Ecosystems in dry regions are generally low in productivity and carbon (C) storage. We report, however, large increases in C sequestration following afforestation of a semi-arid shrubland with Pinus halepensis trees. Using C and nitrogen (N) inventories, based in part on site-specific allometric equations, we measured an increase in the −2 −2 standing ecosystem C stock from 2380 g C m in the shrubland to 5840 g C m in the forest after 35 years, with no significant change in N stocks. The total amount of C produced by the forest was estimated as 6250 g Cm. Carbon sequestration following afforestation was associated with increased N use efficiency as reflected by an overall increase in C/N ratio from 7.6 in the shrubland to 16.6 in the forest. The C accumulation−2 rate in the forest was particularly high for soil organic C (SOC; increase of 1760 g C m −2 −1 or 50 g C m yr ), which was associated with the following factors: 1) Analysis of a 13 small C signal within this pure C3 system combined with size fractionation of soil organic matter indicated a significant addition of new SOC derived from forest vegetation (68% of total forest SOC) and a considerable portion of the old original shrubland SOC (53%) still remaining in the forest. 2) A large part of both new and old SOC appeared to be protected from decomposition as about 60% of SOC under both land-use types were in mineral-associated fractions. 3) A short-term decomposition study indicated decreased decomposition of lower-quality litter and SOC in the forest, based on reduced decay rates of up to 90% for forest compared to shrubland litter. 4) Forest soil included a significant component of live and dead roots. Our results showed the considerable potential for C sequestration, particularly in soils, following afforestation in semi-arid regions, which is particularly relevant in light of persistent predictions of drying trends in the Mediterranean and other regions."
Combined Biogeophysical and Biogeochemical Effects of Large-Scale Forest Cover Changes in the MPI Earth System Model
(2010) Bathiany, S.; Claussen, M.; Brovkin, V.; Raddatz, T.; Gayler, V.
"Afforestation and reforestation have become popular instruments of climate mitigation policy, as forests are known to store large quantities of carbon. However, they also modify the fluxes of energy, water and momentum at the land surface. Previous studies have shown that these biogeophysical effects can counteract the carbon drawdown and, in boreal latitudes, even overcompensate it due to large albedo differences between forest canopy and snow. This study investigates the role forest cover plays for global climate by conducting deforestation and afforestation experiments with the earth system model of the Max Planck Institute for Meteorology (MPI-ESM). Complete deforestation of the tropics (18.75 S–15 N) exerts a global warming of 0.4 C due to an increase in CO2 concentration by initially 60 ppm and a decrease in evapotranspiration in the deforested areas."
Cooperation in Forestry between the Northern and Southern Mediterranean
(1999) Malagnoux, Michele; Lanly, Jean-Paul
"A clear distinction exists between the forest situation in northern Mediterranean and that found in southern Mediterranean countries. Urbanization and a decline in farming in northern Mediterranean countries has left the countryside in an abandoned state, more or less unmanaged by landowners who tend to be unaware of good land management practices. Combustible woody materials are left to accumulate, which combine with the region's dry summer weather and strong winds to heighten the risk of fire."
An Evaluation of Farmers’ Participation in Afforestation Programme in Kogi State, Nigeria
(2010) Saliu, O.J.; Alao, J.S.; Oluwagbemi, T.
"Extensive deforestation has reduced the 65 million hectares of intact forest cover of 1897 in Nigeria to the present 4 million hectares. The consequences of this unhealthy development have resulted to environmental degradation and accelerated wind and water erosion of the fertile land that has also left Nigerian soil too poor for sustainable agricultural production. Reforestation through small-scale village based farmers’ participation now form one of the strategies embarked upon by several agencies in Nigeria including Kogi afforestation project. This study attempts to evaluate farmers’ participation in afforestation project in Kogi State. Structured questionnaire was used to interview 120 participants. Descriptive statistics, adoption index and sigma method were used to describe socio-economic characteristics, participation methods and to measure the level of adoption while chi-square was used to find differences between income generated from adoption of the various afforestation technologies. Findings reveal that 67 percent of the farmers had little or no formal education, more than 30 percent of the farmers underwent passive participation in afforestation while adoption of improved seedlings, exotic trees and pure stand technologies received high score of 4.90, 4.74 and 4.44 respectively. Seed scarification and harvesting by chipping technologies received the least adoption score of 2.61 and 2.94. The chi-square test adjudged that there was a significant difference between income generated and type of technology adopted. This study recommends that more pragmatic interactive participation method that will give room for joint analysis of action plan and formation of local institutions should be put in place."
Geospatial Information Technology for Conservation of Coastal Forest and Mangroves Environment in Malaysia
(2008) Jusoff, Kamaruzaman
"Mangrove forests are one of the most productive and bio-diverse wetlands environments on earth. Yet, these unique coastal tropical forests environment are among the most threatened habitats in the world. Growing in the intertidal areas and estuary mouths between land and sea, mangroves provide critical habitat for a diverse marine and terrestrial flora and fauna. The important need of living being is opportunity to continue their life in sustainable environment and suitable conditions. Potential stand is the place that obtains the possibility of germination and establishment of a plant species according to their physical, chemical, biological demands. In many cases are seen that because of unsuitable selection of site and species, afforestation and reforestation projects after spending time, cost and labor are forced to failure. Therefore, it is an obligation by the relevant authorities, especially Forestry Department to ensure that the rate of seedlings survival in the afforestation and reforestation activities is successfully monitored, mapped and quantified. One of the most efficient techniques available is the use of Geospatial Information Technology consisting of Geographical Information Systems (GIS), Global Positioning System (GPS) and remote sensing (RS). Using this technology and integrating the different thematically maps that shows environmental conditions of specific region, suitable and potential positioning of different species for plantation and rehabilitation programs could be well determined and monitored. For mapping and detection of individual mangrove species for reforestation and afforestation purposes, mathematical functions such as Boolean logic, fuzzy logic, and neural network can be easily applied. It is expected that suitable species-site matching for reforestation and afforestation of mangroves could be implemented with such geospatial tools."
Incorporating Changes in Albedo in Estimating the Climate Mitigation Benefits of Land Use Change Projects
(2008) Bird, D. N.; Kunda, M.; Mayer, A.; Schlamadinger, B.; Canella, L.; Johnston, M.
"Some climate scientists are questioning whether the practice of converting of non-forest lands to forest land (afforestation or reforestation) is an effective climate change mitigation option. The discussion focuses particularly on areas where the new forest is primarily coniferous and there is significant amount of snow since the increased climate forcing due to the change in albedo may counteract the decreased climate forcing due to carbon dioxide removal. In this paper, we develop a stand-based model that combines changes in surface albedo, solar radiation, latitude, cloud cover and carbon sequestration. As well, we develop a procedure to convert carbon stock changes to equivalent climatic forcing or climatic forcing to equivalent carbon stock changes. Using the model, we investigate the sensitivity of combined affects of changes in surface albedo and carbon stock changes to model parameters. The model is sensitive to amount of cloud, atmospheric absorption, timing of canopy closure, carbon sequestration rate among other factors. The sensitivity of the model is investigated at one Canadian site, and then the model is tested at numerous sites across Canada. In general, we find that the change in albedo reduces the carbon sequestration benefits by approximately 30% over 100 years, but this is not drastic enough to suggest that one should not use afforestation or reforestation as a climate change mitigation option. This occurs because the forests grow in places where there is significant amount of cloud in winter. As well, variations in sequestration rate seem to be counterbalanced by the amount and timing of canopy closure. We close by speculating that the effects of albedo may also be significant in locations at lower latitudes, where there are less clouds, and where there are extended dry seasons. These conditions make grasses light coloured and when irrigated crops, dark forests or other vegetation such as biofuels replace the grasses, the change in carbon stocks may not compensate for the darkening of the surface."
Land-Use Effects on Flood Generation: Considering Soil Hydraulic Measurements in Modelling
(2009) Wahren, A.; Feger, K. H.; Schwarzel, K.; Munch, A.
"The investigation in the catchment of the Mulde (51◦ 0 55 N, 13◦ 15 54 E Saxony, Germany) researches the effect of afforestation measures on the soil hydraulic properties. The concept of a 'false chronosequence' was used to quantify the time-dependent dynamical character of the forest impact. Four adjacent plots were identified at a test location with comparable pedological start conditions and a set of tree stands of different age: (1) arable field (initial state); (2) 6-year-old afforestation; (3) 50-year-old afforestation; (4) ancient natural forest (“target” stocking). Water retention curves and unsaturated conductivities were analysed in the lab. In the field, the undisturbed infiltration capacities were measured quantitatively (hood infiltrometer) and qualitatively (brilliant blue tracer). Pronounced differences between all 4 plots were detected. The afforestation causes an increased infiltration and soil water retention potential. Especially the topsoil layers showed a distinct increase in conductivity and portion of coarse/middle pores. The influence of these changes on rainfall-runoff calculations at the test location was analysed in this study."
Urban Forest and Rural Cities: Multi-sited Households, Consumption Patterns, and Forest Resources in Amazonia
(2008) Padoch, Christine; Brondizio, Eduardo; Costa, Sandra; Pinedo-Vasquez, Miguel; Sears, Robin R.; Siqueira, Andréa D.
"In much of the Amazon Basin, approximately 70% of the population lives in urban areas and urbanward migration continues. Based on data collected over more than a decade in two long-settled regions of Amazonia, we find that rural-urban migration in the region is an extended and complex process. Like recent rural-urban migrants worldwide, Amazonian migrants, although they may be counted as urban residents, are often not absent from rural areas but remain members of multi-sited households and continue to participate in rural-urban networks and in rural land-use decisions. Our research indicates that, despite their general poverty, these migrants have affected urban markets for both food and construction materials. We present two cases: that of acai palm fruit in the estuary of the Amazon and of cheap construction timbers in the Peruvian Amazon. We find that many new Amazonian rural-urban migrants have maintained some important rural patterns of both consumption and knowledge. Through their consumer behavior, they are affecting the areal extent of forests; in the two floodplain regions discussed, tree cover is increasing. We also find changes in forest composition, reflecting the persistence of rural consumption patterns in cities resulting in increased demand for and production of acai and cheap timber species."
Using Farm Trees for Fuelwood
(1983) Poulsen, Gunnar
"One of the foundation stones of forest management is forest mensuration - comprising primarily stocktaking of the standing volume of wood and assessment of the growth rate. The basic data for calculating volume are: diameter at breast-height (dbh), the height of the marketable part of the trunk or measurement to the top of tree, and the number of trees per unit area. The current annual increment is found by combining the volume figures with additional parameters for diameter and height growth. The motive for writing this article and for starting by describing the commonly used method for surveying forest resources is a nagging doubt concerning the suitability of this method for assessing the productive potential (in terms of wood) of farm trees and drawing conclusions on this basis concerning the wood supply situation, the need for afforestation, etc."

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