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91.
Susan C. Baker Simon J. Grove Lynne Forster Kevin J. Bonham Dick Bashford 《Forest Ecology and Management》2009
The Warra Silvicultural Systems Trial (SST) in Tasmania, Australia provides a framework for investigating the responses of beetles (Order: Coleoptera) to three alternative systems in lowland wet eucalypt forest: aggregated retention; dispersed retention; and understorey islands retained in clearfelled areas. Beetles from three families known to be sensitive to forest management, the families Carabidae (ground-beetles), Curculionidae (weevils) and Leiodidae (fungus-beetles), were collected with pitfall traps prior to harvest, and in the first and third years post-harvest. The retained aggregates in the aggregated retention system maintained beetle assemblages reasonably typical of mature forests, at least in these early years following harvesting. These aggregates appear to provide a stable habitat, with similar species composition in the first and third years post-harvest. In contrast, the harvested areas of the aggregated retention system contained low numbers of beetle species affiliated with mature forest, as did the understorey islands and the dispersed retention system. Relative to clearfelling, all alternative silvicultural systems appeared to be of some benefit to beetles affiliated with mature forest, but aggregated retention retained far greater numbers of these beetles compared to the other systems in Tasmanian wet eucalypt forest. 相似文献
92.
Adoption of rubber-integrated farm-livelihood systems: contrasting empirical evidence from the Indian context 总被引:2,自引:0,他引:2
This paper examines the influence of important socio-economic, institutional/policy level factors in determining the adoption/non-adoption
of rubber-integrated farming systems in traditional and non-traditional rubber-growing regions in India. The empirical analysis
is based on a survey of rubber growers in the traditional rubber regions of Kerala (south India) and the non-traditional rubber
regions of Assam, Meghalaya, and Tripura (north east India). In sharp contrast to Kerala, where smallholder responses toward
adoption of rubber-integrated farming systems have been lukewarm, the emerging rubber economies (most of which are tribal
communities) of north east (NE) India have shown interest in adopting rubber as an integrated farming system along with pre-existing
land-use livelihood activities. The study clearly demonstrates contrasting empirical evidence of adoption of rubber-integrated
farm-livelihood systems in the rubber-growing regions in Kerala and the NE states in India. The contrasting scenarios of adoption
of rubber-integrated farming systems are mostly explained by region-specific factors dominated by socio-economic, institutional
variables, and policy-level constraints, as also revealed by multivariate analysis. By and large, the findings of the study
have significant bearing on the socio-economic outcomes and the existing institutional development paradigm underlying the
rubber-development programmes introduced in India since independence. The study shows that the existing institutional arrangements
and policies, which evolved historically to facilitate rubber area expansion in the traditional regions (including Kerala),
have been highly instrumental in perpetuating rubber farming as a monoculture system. However, such an institutional mechanism
proves to be highly redundant in the context of the NE states which are otherwise diverse in terms of integrated farm-livelihood
systems and shifting cultivation. 相似文献
93.
Worldwide, fruit-tree-based agroforestry systems have been only modestly studied, although they are common on smallholder
farms. Such systems based on apple (Malus spp.), peach (Prunus spp.), and pear (Pyrus spp.) are common in northwest Guatemala as low intensity homegardens and are known to increase total farm productivity in
communities where farm size is a limiting factor. This study investigated the potential for adoption of fruit-tree-based agroforestry
by resource-limited farmers using ethnographic investigation and linear programming simulations of farm activities at the
household level. Two communities with differing demographics, infrastructure, and access to regional markets were selected
based on the presence of extensive fruit-tree-based agroforestry. The influences of family size, land holdings, and tree and
crop yields on the optimal adoption levels of fruit trees were evaluated through a comparative study of the varying social
and physical infrastructure present in the two communities. Fruit-tree-based agroforestry was potentially more attractive
to relatively prosperous families or those with larger land holdings. Improvements in fruit-tree productivity and interspecies
competition were of greater importance where family land holdings were smaller. The inability of families to produce sufficient
food to meet annual needs, poor fruit quality, and lack of market infrastructure were identified as constraints that limit
adoption. The complementarity of production with the dominant maize (Zea mays) crop, home consumption of fruit, and the potential to generate additional cash on limited land holdings were identified
as factors promoting adoption of fruit-tree-based agroforestry. 相似文献
94.
Our study aimed to assess the effect of dual inoculation with the selected Rhizobium strain KWN35 and the arbuscular mycorrhizal isolate BEG 176 (Glomus etunicatum) on the growth of Calliandra
calothyrsus cultivated under irrigation in the field in Senegal (Dakar) over a period of 24 months. Although plants inoculated with both
microsymbionts grew better (height and root collar diameter) than plants from three other inoculation treatments (control,
single inoculation with KWN35 or BEG 176), these results were not statistically different except at 1 and 5 months after field
transplantation. KWN35 was present in a relatively high percentage of nodules harvested from plants inoculated with this rhizobial
strain either alone or with mycorrhiza (approximately 60% and 40% 1 and 2 years after field transplantation respectively).
The percentage of mycorrhizal root infections was around 60% in the inoculated plants after 12 months with significantly higher
N, P and K foliar contents of trees compared with the non-inoculated controls. However, as for nodulation, by 24 months after
transplantation, there were no significant differences between treatments. We conclude that field inoculation of C. calothyrsus with Rhizobium strain KWN35 and arbuscular mycorrhizal isolate BEG 176 did not have a long-lasting effect on the growth of trees, even when
a majority of nodules were occupied by the inoculated rhizobia and the roots infected by the mycorrhiza. Several reasons can
be postulated for these results, such as a possible effect of soil fertility on the efficiency of the nodules. 相似文献
95.
Ciro Abbud Righi Vincent S. J. A. Couderc Carlos Rodrigues Pereira Hilton Thadeu Zarate do Couto Luciana Duque Silva 《Journal of Sustainable Forestry》2013,32(1):75-87
ABSTRACTEucalyptus is widely cultivated in homogeneous monocultures throughout the world alongside plants of the same age. Furthermore, the productivity of forest stands is highly dependent on how solar radiation is intercepted and used. Meanwhile, it is possible to consider cultivating trees of different ages in the same area, and thus under different regimes of available solar radiation, creating a sequence of plantings and harvestings and to develop Eucalyptus-based agroforestry systems. We have examined biomass accumulation of Eucalyptus camaldulensis along a shade gradient. Eucalyptus trees presented power-law responses to increasing irradiance for biomass, indicating it has low plasticity and is unable to maintain growth under lower irradiance levels. Biomass partitioning showed no dependence on available irradiation. Leaf density presented very little increase toward sunnier places meaning that an increment in Eucalyptus biomass would be mostly due to its increase in size and thus higher radiation interception. Careful management of shade will be a key consideration for the integration of Eucalyptus into agroforestry. With knowledge of the growth habits of different species, we will have the potential to propose more perennial ways in which to manage land and reduce anthropogenic disturbances by avoiding clear-cuts of areas that removes all plant structures. 相似文献
96.
《Journal of Sustainable Forestry》2013,32(1-2):245-263
Summary Land managers need vegetation maps to inventory, monitor, and manage ecological resources across multiple spatial and temporal scales. Current vegetation maps usually only describe one vegetation characteristic, such as cover types, across the landscape. Although these maps provide important information for land management, they often fall short of addressing key issues like forest health and ecosystem management. In this paper we present an integrated approach where three different vegetation classifications are used in concert to spatially characterize many ecological attributes such as snag densities, insect susceptibility, and fire behavior across the landscape. Two examples from the Pacific Northwest are used to illustrate how this approach can be used to describe fuel characteristics and resource hazard across multiple scales. 相似文献
97.
W. M. Loker 《Agroforestry Systems》1994,25(3):227-241
Low external input agroforestry systems hold great promise as alternative, sustainable production systems for small-to-medium farmers in the Amazon Basin. The design of such systems is considered essential to stabilize agricultural production and avoid the cycle of continuing destruction of primary forest [Anderson A (1990) In: Anderson A (ed) Alternatives to Deforestation: Steps toward Sustainable Use of the Amazon Rain Forest pp 3–23. Columbia University Press, New York]. In order to be successful, these systems must be compatible with local ecological conditions and adoptable by farmers. Currently, many small-to-medium producers in the Amazon Basin use a slash and burn agricultural strategy that combines annual cropping with cattle grazing in mixed farming systems. While cattle play an important role in household economic survival, grazing-induced land degradation threatens the long-term viability of these farms [Loker W (1993) Human Organization 52(1)14–24]. This paper presents a model of a low external input agroforestry system that incorporates farmer preferences and practices but uses well-adapted grass-legume pastures, rotational grazing and the management of natural forest regeneration to enhance productivity in an ecologically sound manner. This system provides farmers with the benefits of both annual crops and cattle raising, avoids the land degradation that characterizes current practices and effectively incorporates trees into the production system. 相似文献
98.
99.
As a low-tech, labour intensive and supplier-dominated industry, the wooden furniture industry's pattern of innovation is widely acknowledged as business driven. This paper's main objective is to ascertain the roles played by the various innovation actors and their linkages to the process of technological innovations in the wooden furniture industry. Empirical evidence is derived from a narrative case study of the Muar furniture cluster in Malaysia. The main findings from this study indicate that the dynamics of innovation in Malaysia's wooden furniture industry are mainly business-led and are characterised as collective innovation. In this regard, the roles played by the immediate business environment such as suppliers, customers, competitors, and retailers are of paramount importance. These innovation actors have been linked closely to firms in their surge for technological advancement. Universities and government organisations do not feature in the operations of these firms. 相似文献
100.