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The Shola (Tropical Montane Forest)-Grassland Ecosystem Mosaic of Peninsular India: A Review

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American Journal of Plant Sciences 2012年第11期3卷 1632-1639页

作者： Milind Bunyan Sougata Bardhan shibu jose School of Forest Resources and Conservation Gainesville USA The Center for Agroforestry School of Natural Resources 203 Anheuser-Busch Natural Resources Building University of Missouri Columbia USA.

Tropical montane forests (alternatively called tropical montane cloud forests or simply cloud forests) represent some of the most threatened ecosystems globally. Tropical montane forests (TMF) are characterized and defined by the presence of persistent cloud cover. A significant amount of moisture may be captured through the condensation of cloud-borne moisture on vegetation distinguishing TMF from other forest types. This review examines the structural, functional and distributional aspects of the tropical montane forests of peninsular India, locally known as shola, and the associated grasslands. Our review reveals that small fragments may be dominated by edge effect and lack an “interior” or “core”, making them susceptible to complete collapse. In addition to their critical role in hydrology and biogeochemistry, the shola-grassland ecosystem harbor many faunal species of conservation concern. Along with intense anthropogenic pressure, climate change is also expected to alter the dynamic equilibrium between the forest and grassland, raising concerns about the long-term sustainability of these ecosystems.

关键词： Shola Forests Western Ghats GIS Biodiversity Species Composition Shola Fragments

Nutrient Use Efficiency of Three Fast Growing Hardwood Species across a Resource Gradient

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Open Journal of Forestry 2012年第4期2卷 187-199页

作者： Dawn E. Henderson shibu jose Department of Forestry University of Missouri Columbia USA Open Rivers and Wetlands Field Station Missouri Department of Conservation Jackson USA

Attitudes regarding traditional energy sources have shifted toward renewable resources. Specifically, short-rotation woody crop supply systems have become more prevalent for biomass and biofuel production. However, a number of factors such as environmental and inherent resource availability can limit tree production. Given the intensified demand for wood biomass production, forest and plantation management practices are focusing on increasing productivity. Fertilizer application, while generally one of the least expensive silvicultural tools, can become costly if application rates exceed nutrient uptake or demand of the trees especially if it does not result in additional biomass production. We investigated the effect of water and varying levels of nitrogen application (56, 112, and 224 kg·N·haǃ·yrǃ) on nutrient content, resorption efficiency and proficiency, N:P and the relationship with ANPP, as well as leaf- and canopy-level nutrient use efficiency of nitrogen, phosphorus, and potassium for Populus deltoides, Quercus pagoda, and Platanus occidentalis. P. deltoides and P. occidentalis reached their maximum nitrogen budget with the application of water suggesting old agricultural fields may have sufficient nutrient levels to sustain short-rotation woody crops negating the application of additional nitrogen for these two species. Additionally, for P. deltoides and Q. pagoda application of nitrogen appeared to increase the uptake of phosphorus however, resorption efficiency for these two species were more similar to studies conducted on nutrient poor sites. Nutrient resorption proficiency for all three nutrients and all three species were at levels below the highest rates of nitrogen application. These findings suggest maximum biomass production may not necessarily be tied to maximum nutrient application.

关键词： Nutrient Use Efficiency Resorption N:P Biomass Production

The Ecological Classification of Coastal Wet Longleaf Pine (Pinus palustris) of Florida from Reference Conditions

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American Journal of Plant Sciences 2012年第9期3卷 1205-1218页

作者： George L. McCaskill shibu jose Center for Agroforestry School of Natural Resources University of Missouri Columbia USA Forest Inventory & Analysis Northern Research Station USDA Forest Service Newtown Square USA

Tropical storms, fire, and urbanization have produced a heavily fragmented forested landscape along Florida’s Gulf coast. The longleaf pine forest, one of the most threatened ecosystems in the US, makes up a major part of this fragmented landscape. These three disturbance regimes have produced a mosaic of differently-aged pine patches of single or two cohort structures along this coastline. The major focus of our study was to determine reference ecosystem conditions by assessing the soil biochemical properties, overstory stand structure, and understory plant species richness along a patch-derived 110-year chronosequence in order to accurately evaluate on-going longleaf pine restoration projects. This ecological dataset was also used to classify each reference patch as mesic flatwoods, wet flatwoods, or wet savanna. All of the reference locations were found to have similar soil types with no significant differences in their soil biogeochemistry. Mean diameter-at-breast height (DBH), tree height, and patch basal area increased as mean patch age increased. Stand growth reached a plateau around 80-90 years. Shrub cover was significantly higher in the matureaged patches (86-110 years) than in the young (6-10 years) or mid-aged (17-52 years) patches, despite prescribed fire. Plant species diversity as indicated by the Shannon-Wiener index decreased with patch age. Soil biogeochemical properties, forest structure, and understory species composition were effective for ecologically classifying our pine patches as 55 % mesic flatwoods, 20% wet flatwoods, and 25% wet savanna. Florida’s Gulf coastal wet longleaf pine flatwoods attain a structural and plant species equilibrium between 80-90 years.

关键词： Forest Structure Species Richness Restoration Pine Patches Shannon-Wiener Soil Biogeochemistry

Edge Effects in Small Forest Fragments: Why More Is Better?

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American Journal of Plant Sciences 2012年第7期3卷 869-878页

作者： Milind Bunyan shibu jose Robert Fletcher Department of Wildlife Ecology and Conservation University of Florida Gainesville USA. School of Forest Resources and Conservation University of Florida Gainesville USA The Center for Agroforestry School of Natural Resources University of Missouri Columbia USA

Edge to interior gradients in forest fragments can influence the species composition and community structure as a result of variations in microenvironment and edaphic variables. We investigated the response of microenvironment and edaphic variables to distance from a tropical montane forest (locally known as shola)-grassland edge using one-edge and multiple-edge models. The edpahic variables did not show any differences between the grassland and shola soils. We observed that conventional one-edge models sufficiently explained variation trends in microenvironment along the edge to interior gradient in large fragments. As with other studies on small fragments though, we observed no edge effects with the use of a conventional one-edge model. However, the inclusion of multiple edges in small fragments signifycantly improved model fit. We can conclude that small fragments dominated by edge habitat may in fact resemble larger fragments with the inclusion of multiple edges. Our models did not evaluate non-linear effects which often better explain patterns in edge-interior gradients. The incorporation of such non-linear models in the system might further improve model fit.

关键词： Edge-Interior Gradients Multiple Edges Microenvironment Tropical Montane Forests Shola-Grassland Ecosystem Western Ghats India

A Global Analysis of Temperature Effects on Populus Plantation Production Potential

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American Journal of Plant Sciences 2015年第1期6卷 23-33页

作者： Natalya K. Kutsokon shibu jose Eric Holzmueller The Center for Agroforestry University of Missouri Columbia MO USA Institute of Cell Biology and Genetic Engineering NAS of Ukraine Kiev Ukraine Department of Forestry Southern Illinois University Carbondale IL USA

The genus Populus contains some of the most economically important tree species and hybrids in the world. We compared productivity of short and long-rotation poplar plantations using published data from 23 countries to determine if climate, particularly temperature, had any effect on the observed patterns of productivity. We discovered that climate factors (related to temperature) and clone origin (pure species or hybrids) slightly influenced productivity of long rotation forests more than short rotation plantations. While long rotation plantation productivity exhibited positive correlations with increasing temperature during winter and decreasing heat during summer, short rotation plantations showed weak positive relationship among productivity and increasing yearly temperature and the number of hot days. It was apparent that short rotation plantations productivity was less dependent on regional climatic variables or origin of clone. However, it appears that overall, regardless of the system, Populus species are generally adapted to a range of climatic conditions where they are planted.

关键词： Poplar Populus sp. Hybrids Fast-Growing Plantations Intensive Forestry Short and Long Rotation Plantations Stem Volume Climate