Matrix Based Forest Management
An emerging paradigm for biodiversity conservation
Forest patches must be taken care of
A land area of more than 0.5 ha, with a canopy cover of more than 10 percent and trees able to reach a minimum height of 2-5 metres at maturity in situ can be called a forest. It includes areas with rattans, bamboos and palms provided that height and canopy cover criteria are met. Forest also includes forest roads, firebreaks, meadows, other small open areas, windbreaks, shelterbelts, corridors of trees, national parks, nature reserves and other protected areas which have specific scientific, historical, cultural or spiritual interest. According to Lindemayer & Franklin (2002), matrix comprises landscape areas that are not designated primarily for conservation of natural ecosystems, ecological processes, and biodiversity regardless of their current condition (natural or developed). Massive deforestation has led to striking fragmentation of natural forests throughout the world. Fragmented forests are composed of small patches. Usually human-fragmented forests maintain some degree of terrestrial connectivity via the matrix of modified habitats surrounding fragments. Biodiversity is impacted by the sizes of forest patches, remaining continuous forest, and the intervening matrix. The matrix is important in the evolution of fragment dynamics for several reasons. The forest matrix often acts as a corridor for the movements of species across the landscape. It exerts a strong influence on remnant community dynamics. Species associated with the matrix alters the species composition of some taxonomic groups. Matrix influences the edge effects of forest fragments. The matrix surrounding matrix has pervasive effects on vertebrate communities in forest fragments. A substantial number of nominally primary-forest species are capable of using matrix habitats, at least when large forest tracts which provide potential sources of immigrants are nearby. Some primary-forest species use matrix habitats for movement and/or reproduction in the tropical forests. The vulnerability of species in fragments is related to their ability to use matrix. A disappeared species from the fragments may be colonized in the matrix. Structural diversity of both habitat remnants and surrounding matrix is an important factor for explaining plant population dynamics and ecosystem functions in human-impacted landscapes. Forest fragmentation severely threatens the maintenance of biodiversity and the functioning of ecosystem worldwide. Small population size due to habitat loss, collapsed metapopulation by habitat isolation, and decreased individual potentiality due to edge effects are pivotal processes that frequently lead to the extinction of species in fragmented landscapes. These adverse effects are mainly reported in landscapes where remaining habitat fragments are embedded in a highly contrasting, inhospitable matrix of degraded habitat. In the tropics and subtropics most of the natural forests are characterized by a continuum mosaic of patches with different degrees of degradation and structural disparity. Matrix has a greater influence on biodiversity patterns in landscape mosaics and on plant-animal relationship. Forest fragmentation disrupts mutualisms due to habitat loss or increased isolation, and increased antagonisms due to edge effects. The surrounding matrix of the remnant habitats support part of the populations of seed dispersers, serve as temporary habitats, and even favour their individual movements when moving across the whole landscape. The matrix habitats influence ecological processes such as plant-animal interactions within remnant habitat patches in fragmented landscapes. The matrix offers food resources and even breeding areas to frugivores, leading them to tolerate, exploit food resources, and even increase in abundance in matrix habitats. The presence of scattered trees enriches the structure of pasture matrix. Scattered trees not only provide fleshy-fruited resources for avian frugivores, but resting sites when flying through the landscape. As a result, landscape connectivity is enhanced through seed dispersion. Scattered trees act as bridge between the patches. The matrix habitats lead frugivorous birds to perceive the landscape as a continuum rather than as discrete habitat patches. Seeds within unconnected patches suffer stronger predation than those located within connected patches. Recruitment rates are lower in unconnected patches, thus collapsing regeneration. The biodiversity conservation has to involve maintenance of habitat at multiple spatial scales, from the scale of centimeters to that of thousands of hectares. For example, critical habitat for some species may be the provision of an individual structure, such as a standing dead tree or a log on the forest floor, in an otherwise human-modified environment. For other species it may be the provision of a large natural reserve, with a diversity of habitat conditions. Resource management practices that maintain or improve the suitability of the matrix are fundamental to the conservation of biodiversity. In fact, approaches to matrix management have major implications for fundamental tenets of conservation biology as reserve design, metapopulation processes, extinction proneness, and connectivity and species persistence in human-modified landscapes. The future of the vast majority of the earth's species will depend on how the matrix is managed -- including not only the human-perceived habitat patches, but also the extensive areas that surround them. It is highly important to give major attention to the matrix if programmes to conserve the world's biological diversity are to succeed. This includes facilitating the multiple roles of the matrix in management programmes, including provision of habitat and facilitation of movement. Improving matrix quality may lead to higher conservation returns than manipulating the size and configuration of remnant patches for many of the species that persist in the aftermath of habitat destruction. The policy makers and the conservation scientists must realize that conservation of biological diversity is not primarily a set-aside issue that can be dealt with by reserving or modifying management on huge landscape; rather, it is a pervasive issue that must be considered on every acre of land that they manage. For the matrix management we should consider the following points: 1) the importance of the matrix in key areas of ecology such as metapopulation dynamics, habitat fragmentation, and landscape connectivity; 2) general principles for matrix management; 3) using natural disturbance regimes to guide human disturbance; 4) landscape-level and stand-level elements of matrix management; 5) the role of adaptive management and monitoring; 6) social dimensions and tensions in implementing matrix-based forest management; and 7) the relationship among patch occupancy, patch area and isolation. We need effective models of our forest management, based on locally appropriate paradigms and application, in which the concept of sustainability is set in the broader context of managing production forests. Albeit a network of protected areas is necessary for conserving natural forests and their biodiversity. High forest fragmentations will be vulnerable for the biodiversity to sustain. Woodlot Plantation forests, therefore, need to be managed for more than just timber production -- also for objectives such as supporting local livelihoods, biodiversity conservation, and environmental services, including carbon capture and storage. For conserving biodiversity, this may require thinking in terms of managing the landscape as continuum of patches, corridors, and matrices.
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