Introduction Article –
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 meta-population 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, meta-population 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 meta-population 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.
“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.”
Interview with Mizanur by Willi
Define sustainability for us?
Thank you Willi Paul! Sustainability is the meeting of present needs without compromising the ability of future generations to meet their own needs. In the conservation biology, sustainability describes how biological systems remain diverse and productive over time. FAO defines sustainable forest management as: The stewardship and use of forests and forest lands in a way, and at a rate, that maintains their biodiversity, productivity, regeneration capacity, vitality and their potential to fulfill, now and in the future, relevant ecological, economic and social functions, at local, national, and global levels, and that does not cause damage to other ecosystems. I define sustainable forest management as keeping balance between the demands of forest products and biodiversity conservation.
Is forest management now in the hands of scientists or the law makers?
Forestry is always both an arena of scientific investigation and a method for how forests should be managed. In forest management, managers define the nature of the problems at first, the second the scientist does the same but from the scientific point of view and finally the law makers take the bucket of facts from the scientists. So, forest management is a joint effort of forest managers, scientists and the law makers. Obviously, scientists are the play makers of this game.
Is subsistence the same as sustainability?
No, it is not the same; rather there is no significant difference between the subsistence and commercial forest. A subsistence forest addresses the subsistence needs of local people and keeps them gainfully employed. A subsistence forest can be a sustainable forest through reconciling the subsistence needs of people with conservation.
What is a “production forest?” What else “lives there?”
The forests which are used for the production of different commodities like timber, non timber products and other services are termed as production forests. The level of biodiversity depends on the forest type, location and management practices. Usually production forests offer less habitat diversity and support fewer species than do natural protected forests.
How do you propose to heal inhospitable sections of degraded habitat?
• Protecting the degraded habitats from further destructions
• Rebuilding connectivity among small adjacent protected areas by including intervening habitat and promoting reforestation of the landscape
• Protecting forest edges against structural damage
• Stopping colonization of exotics
• Near natural management of the buffer zones
• Managing forest matrix
• Facilitating natural regeneration
• Initiating rehabilitation and restoration programme
• Making wildlife corridors through connecting areas of remnant forest to provide wider ranges and more protection for native plants and animals
• Arresting the inevitable decline of the gene pool in isolated areas
• Re-colonizing the wildlife species into their original habitat
• Ex-situ conservation of gene pools of very rare species
“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.”
How does the forest become a matrix of scars and remnants? Who are the culprits?
A forest becomes a remnant in two ways:
1.ecosystem is partially removed, creating ‘islands’ surrounded by farmland; and
2. ecosystems is degraded by the loss of species and disruption of their ecological processes. The natural forest degradation occurs in different patterns, like in patches (e.g.), in waves (e.g. by urbanization) or as linear (e.g. by construction of roads).
The following factors are involved for the habitat destruction in the tropics:
• faulty land ownership pattern
• shifting cultivation
• illegal and commercial logging
• high demand of timber
• scarcity of fuel wood
• destruction of natural vegetation
• soil disturbances
• inadequate valuation of forests as resources, inadequate protection
• establishment of infrastructures and transport networks
• extractive activities
• inappropriate interventions
• construction of dams for hydropower sources
• poverty, excessive extraction of non-timbering plants
• lack of philosophical and ethical attitudes
• animal grazing
• litter sweeping
• encroachment and land grabbing
• economic attitudes
• greed and corruption
• social structures
• wars and social conflicts
• introduction of exotic species
• over-exploitation and
• brick field.
Why the people are not responsible for the damage paying to fix it?
State is the owner of the forests in most of the third world countries. Sometimes the responsible authority does not try to sue the culprits due to several reasons: land disputes, ethnic conflicts, muscle power of the culprits, moving of illegal land-grabbers and loggers into the forest far ahead of the government, corruption of the forest authority, insufficient staffs and weakness of existing laws. Unlike most criminal organizations, the mafia has wide popular support in the Amazonian Rain Forests territory. So, it is very difficult to make the culprits responsible and fix the damage to pay.
There are many voices and opinions on “biodiversity.” What is your definition?
Biodiversity is the variety; intra and interrelationships; and interactions of or among all floras, faunas and microorganisms living on this planet. It includes the variety of their genomes, richness, structures, habitats, natures and ecosystems.
Isn’t biodiversity different to a logger vs. an eco-conservationist?
A logger defines biodiversity as the diversity of merchantable, quality, vital and valuable timbering plants in the forests. .:D
An eco-conservationist defines biodiversity as the diversity within species, between species and of ecosystems.
What are the leading resource management practices in this field?
I strongly believe that ‘People Centered Conservation and Development’ is the best management practice in the natural resource management. This is community based natural resource management, which reduces human pressures on biodiversity, leading to improved conservation; and aspires to combine social development with conservation goals. It deals with biodiversity conservation objectives through the use of socio-economic investment tools.
Are you advocating growing crops on all forest patches?
Not at all, growing crops on forest patches destroys the characteristics of the forests, makes the habitats inhospitable for natural regenerations and affects the biodiversity adversely.
Please define localization.
In the conservation biology, localization may be defined as the process of adopting conservation programme for a particular habitat in accordance with desired local “look-and-feel’.
How can the local population assist in fighting against clear-cutting?
• Land based resistance
• Awareness development against clear cut
• Public relations campaigning for environmental sustainability
• Helping law enforcing agencies to capture the illegal loggers and land grabbers
• Forest Love Movement
• Boycotting the illegal loggers within the social structure
* * * * * * *
Dr. Md. Mizanur Rahman’s Bio-
• Bachelor of Science in Agriculture from Bangladesh Agricultural University
• Master of Science in Entomology from Bangladesh Agricultural University
• PhD on Biodiversity Science from the University of Natural Resources and Life Sciences, Vienna
• An environmentalist
• A biodiversity specialist
• A researcher
• A columnist
• A journal reviewer
• A civil servant of Bangladesh
• An Executive Magistrate
Dr. Md. Mizanur Rahman , Biodiversity Specialist
Senior Assistant Commissioner
Mizan_peroj at yahoo.com
entomol_mizan at yahoo.com
mizan.rahman at boku.ac.at