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1.
This study aimed to analyze the ecological, socio-economic and policy implications of land-use diversity in a traditional
village landscape (900–1,000 m amsl.) in the Garhwal region of Indian Himalaya. The village landscape was differentiated into three major land-use types viz.,
forests, settled agriculture and shifting agriculture. Settled agriculture was further differentiated into four agroecosystem
types viz., homegarden system (HGS), rainfed agroforestry system (RAS), rainfed crop system (RCS) and irrigated crop system
(ICS), and shifting agriculture system (SAS) was differentiated into different stages of a 4-year long cropping phase and
a 7-year long fallow phase, and forests into Community Forests (CF) and Reserve Forests (RF). HGS is the most productive agroecosystem,
with soil organic carbon and nutrient concentrations significantly higher than all other forest/agricultural land-uses. Farmers
capitalize upon crop diversity to cope with the risks and uncertainties of a monsoon climate and spatial variability in ecological
factors influencing productivity. The SAS, a land-use adopted as a means of acquiring inheritable rights over larger land
holdings provided in the policies during the 1890s, is less efficient in terms of land productivity than the traditional RAS
and HGS but is maintained for its high labour productivity coupled with availability of high-quality fuelwood from fallow
vegetation. Dominance of fodder trees in the RAS seems to derive from policies causing shortage of fodder available from forests.
Cultural norms have favoured equity by allowing hiring of labour only from within the village community and income from non-timber
forest products only to the weaker section of the society. Conversion of rainfed to irrigated cropping, a change facilitated
by the government, improves agricultural productivity but also increases pressure on forests due to higher rates of farmyard
manure input to the irrigated crops. Existing forest management systems are not effective in maintenance of a large basal
area in forests together with high levels of species richness, soil fertility and resistance to invasive alien species Lantana camara. Farmers have to spend huge amount of labour and time in producing manure, managing livestock and other subsidiary farm activities.
Interlinkages among agriculture, forests and rural economy suggest a need of replacing the present policies of treating agricultural
development, forest conservation and economic development as independent sectors by an integrated sustainable development
policy. The policy should promote technological and institutional innovations enabling parallel improvements in agricultural
productivity and functions of forest ecosystems. 相似文献
2.
The Central Himalayan region is suffering from severe ecological problems as a consequence of deforestation and that threatens
the subsistence population of the region. We analyze this problem and propose a plan for ecologically sustainable development
for the region based on an analysis of the interrelationships of various ecosystems, particularly cropland and forest ecosystems,
around which most human activities are concentrated. Each energy unit of agronomic yield leads to expenditure of about 12
energy units of forest/grazing land energy. Because with rapidly declining forest area, this form of agriculture is no longer
sustainable and cannot be converted into a fossil fuel-based agriculture, we propose that agriculture in the mountain region
has to be largely replaced with farm forests to revitalize the environment and to generate the basic needs of the subsistence
economy of the hill population whose food grain needs can be met from the plains. We conclude by describing the advantages
that are likely to accrue to the people for their long-term future. In terms of both energy and money, the value of resources
collected from the forest to support agriculture in the present systems far exceeds the value of food grain that would be
required to enable the proposed farm forest-based systems to function. At regional level, the proposed system would generate
more energy than the existing systems, not only because the productivity of forest is about tenfold greater than that of cropland,
but also because the proposed plan promotes recovery of various ecosystems. 相似文献
3.
Poverty, hunger and demand for agricultural land have driven local communities to overexploit forest resources throughout
Ethiopia. Forests surrounding the township of Humbo were largely destroyed by the late 1960s. In 2004, World Vision Australia
and World Vision Ethiopia identified forestry-based carbon sequestration as a potential means to stimulate community development
while engaging in environmental restoration. After two years of consultation, planning and negotiations, the Humbo Community-based
Natural Regeneration Project began implementation—the Ethiopian organization’s first carbon sequestration initiative. The
Humbo Project assists communities affected by environmental degradation including loss of biodiversity, soil erosion and flooding
with an opportunity to benefit from carbon markets while reducing poverty and restoring the local agroecosystem. Involving
the regeneration of 2,728 ha of degraded native forests, it brings social, economic and ecological benefits—facilitating adaptation
to a changing climate and generating temporary certified emissions reductions (tCERs) under the Clean Development Mechanism.
A key feature of the project has been facilitating communities to embrace new techniques and take responsibility for large-scale
environmental change, most importantly involving Farmer Managed Natural Regeneration (FMNR). This technique is low-cost, replicable,
and provides direct benefits within a short time. Communities were able to harvest fodder and firewood within a year of project
initiation and wild fruits and other non-timber forest products within three years. Farmers are using agroforestry for both
environmental restoration and income generation. Establishment of user rights and local cooperatives has generated community
ownership and enthusiasm for this project—empowering the community to more sustainably manage their communal lands. 相似文献
4.
In the present study, forest biomass (fuelwood, leaf fodder, leaf-litter and non-timber forest products) consumption patterns have been evaluated in the villages of Govind Wildlife Sanctuary, Uttarakhand, Western Himalaya, India. The average fuelwood consumption in the selected villages was estimated at 3.14 kg/capita/day and its energy equivalent was found 52.74 MJ/capita/day. The average leaf fodder and leaf-litter consumption was estimated at 2.70 and 2.40 kg/unit/day, respectively, and the same pattern was estimated for energy equivalent. People's perception on impacts of conservation measures and resources utilization rights were also analysed. Our results emphasized the need for regular assessment of forest resources, particularly in protected areas, where access to natural resources have been denied due to legal restrictions. The study could be a pilot to strengthen the conservation measures across the protected area network by understanding the dynamics of anthropocentric activities and their subsequent impacts on forest resources. 相似文献
5.
John J. Metz 《Environmental management》1994,18(3):371-390
This paper describes forest product use at Chimkhola, an upper elevation village of west central Nepal. Villagers have large
herds of livestock that they use to fertilize agricultural fields by holding the animals on cropland for one to several weeks
prior to planting. Herds are moved sequentially from one group of fields to another until all are planted, and then families
take animals into the forests. Herders, therefore, live in temporary shelters away from the homestead throughout the year,
and for much of the year feed their livestock fodder cut from forest trees. By combining repeated interviews of sample households,
one-time interviews with a large sample of village families, and direct measurements of forest products being used, I found
that livestock maintenance consumes 74% of the hand-harvested wild biomass: 26.4% for green fodder, 32.3% for fuelwood at
the herder's hut, and 13.8% for construction of the herder's hut. Fuelwood burned at the homestead is the next largest consumer,
17.6%. Villagers also use small amounts of forest materials for house construction, charcoal, agricultural implements, and
bamboo for baskets and mats. The large amounts used by herders and livestock at Chimkhola mean that wild vegetation use there
far exceeds the measurements made by previous reliable studies at other communities. This system of forest use is, however,
degrading Chimkhola's forests and gradually converting them to shrublands. 相似文献
6.
Protected areas (PAs) are cornerstones of biodiversity conservation, but small parks alone cannot support wide-ranging species,
such as the tiger. Hence, forest dynamics in the surrounding landscapes of PAs are also important to tiger conservation. Tiger
landscapes often support considerable human population in proximity of the PA, sometimes within the core itself, and thus
are subject to various land use activities (such as agricultural expansion and road development) driving habitat loss and
fragmentation. We synthesize information from 27 journal articles in 24 tiger landscapes to assess forest-cover dynamics in
tiger-range countries. Although 29% of the PAs considered in this study have negligible change in overall forest cover, approximately
71% are undergoing deforestation and fragmentation. Approximately 58% of the total case studies have human settlements within
the core area. Most changes—including agricultural expansion, plantation, and farming (52%), fuelwood and fodder collection
(43%), logging (38%), grazing (38%), and tourism and development (10%)—can be attributed to human impacts largely linked to
the nature of the management regime. This study highlights the need for incorporating new perspectives, ideas, and lessons
learned locally and across borders into management plans to ensure tiger conservation in landscapes dominated by human activities.
Given the increasing isolation of most parks due to agricultural, infrastructural, and commercial developments at the periphery,
it is imperative to conduct planning and evaluation at the landscape level, as well as incorporate multiple actors and institutions
in planning, instead of focusing solely on conservation within the PAs as is currently the case in most tiger parks. 相似文献
7.
Soil erosion is accelerating in developing countries of Asia, Africa, and Latin America. It has threatened the livelihood
of millions of peasants, for agriculture is their economic mainstay. A probe into the forces causing erosion reveals that
the elite’s resolve to accumulate ever more wealth and to maintain, consolidate, or expand their sociopolitical power and
the necessity of the poor to fulfill their requirements of food, fuelwood, and fodder are the two major factors accelerating
soil erosion. Unless the vast masses of poor people are integrated into the national mainstream through the implementation
of equitable and redistributive development policies, it is impossible to control the accelerating rate of soil erosion and
thus to achieve the objective of sustainable development.
In this article, the phenomenon “soil erosion” is studied with the sol e focus on causation through anthropogenic factors. 相似文献
8.
Applying Gap Analysis and a Comparison Index to Evaluate Protected Areas in Thailand 总被引:1,自引:0,他引:1
Trisurat Y 《Environmental management》2007,39(2):235-245
Protected areas in Thailand were first established 40 years ago. The total area of existing protected areas covers 18.2% of
the country’s land area and the Class 1 Watershed, another form of protection, encompasses 18.1%. The government of Thailand
intends to increase protected area systems to 25% of the country in 2006 and 30% in 2016. There are always questions arising
about how much is enough protected areas to effectively protect biodiversity. The objective of this article is to assess the
representation of ecosystems in the protected area network. This article also recommends which underrepresented ecosystems
should be added to fill the gaps in representativeness. The research applies a gap analysis and a comparison index to assess
the representation of ecosystems within the protected area network. The spatial analyses were applied to measure three aspects
of representativeness, namely forest type, altitude, and natural land system. The analyses indicate that the existing protected
area system covers 24.4% of the country’s land area, nearly meeting the 25% target proposed by the National Forest Policy;
and 83.8% of these areas are under forest cover. Most protected areas are situated in high altitudes, where biological diversity
is less than in lowlands. Mangrove forest and riparian floodplain are extremely underrepresented in the existing system. Peat
swamp forest, dry dipterocarp forest, and beach forest are relatively well represented. In addition, these five ecosystems
are threatened by human pressures and natural disasters; therefore, they should be targeted as high priorities for the selection
of new reserves. Future research should incorporate aquatic and marine ecosystems, as well as animal distributions, which
were not included in this research due to data unavailabilities. 相似文献
9.
Quantifying Terrestrial Ecosystem Carbon Dynamics in the Jinsha Watershed, Upper Yangtze, China from 1975 to 2000 总被引:1,自引:0,他引:1
Shuqing Zhao Shuguang Liu Runsheng Yin Zhengpeng Li Yulin Deng Kun Tan Xiangzheng Deng David Rothstein Jiaguo Qi 《Environmental management》2010,45(3):466-475
Quantifying the spatial and temporal dynamics of carbon stocks in terrestrial ecosystems and carbon fluxes between the terrestrial
biosphere and the atmosphere is critical to our understanding of regional patterns of carbon budgets. Here we use the General
Ensemble biogeochemical Modeling System to simulate the terrestrial ecosystem carbon dynamics in the Jinsha watershed of China’s
upper Yangtze basin from 1975 to 2000, based on unique combinations of spatial and temporal dynamics of major driving forces,
such as climate, soil properties, nitrogen deposition, and land use and land cover changes. Our analysis demonstrates that
the Jinsha watershed ecosystems acted as a carbon sink during the period of 1975–2000, with an average rate of 0.36 Mg/ha/yr,
primarily resulting from regional climate variation and local land use and land cover change. Vegetation biomass accumulation
accounted for 90.6% of the sink, while soil organic carbon loss before 1992 led to a lower net gain of carbon in the watershed,
and after that soils became a small sink. Ecosystem carbon sink/source patterns showed a high degree of spatial heterogeneity.
Carbon sinks were associated with forest areas without disturbances, whereas carbon sources were primarily caused by stand-replacing
disturbances. It is critical to adequately represent the detailed fast-changing dynamics of land use activities in regional
biogeochemical models to determine the spatial and temporal evolution of regional carbon sink/source patterns. 相似文献
10.
PUA KUTIEL 《Environmental management》1999,23(3):401-408
area cells (the areas between the tracks) increased geometrically in the unprotected area, while the increase in the protected area
was linear; and (3) most area cells (50%–70%) in the protected area in each of the years analyzed (except 1944) were smaller
than 10 ha in size. However, an area cell greater than 100 ha has always been observed. In contrast, in the unprotected site
the number of area cells increased with time while their area size decreased. Twenty-seven percent of the unprotected area
is composed at present of area cells smaller in size than 1 ha. The development of a track system in the protected site changed
moderately with a few peaks during the past 50 years. This trend is a result of land management policies that actively promote
sustainable ecotourism. However, in the unprotected open area, the track system has changed continuously and drastically due
to a lack of land conservation management. 相似文献
11.
According to the Seventh National Forest Inventory (2004–2008), China’s forests cover an area of 195.45 million ha, or 20.36%
of the total land area. China has the most rapidly increasing forest resources in the world. However, China is also a country
with serious forest pest problems. There are more than 8,000 species of potential forest pests in China, including insects,
plant diseases, rodents and lagomorphs, and hazardous plants. Among them, 300 species are considered as economically or ecologically
important, and half of these are serious pests, including 86 species of insects. Forest management and utilization have a
considerable influence on the stability and sustainability of forest ecosystems. At the national level, forestry policies
always play a major role in forest resource management and forest health protection. In this paper, we present a comprehensive
overview of both achievements and challenges in forest management and insect pest control in China. First, we summarize the
current status of forest resources and their pests in China. Second, we address the theories, policies, practices and major
national actions on forestry and forest insect pest management, including the Engineering Pest Management of China, the National
Key Forestry Programs, the Classified Forest Management system, and the Collective Forest Tenure Reform. We analyze and discuss
three representative plantations—Eucalyptus, poplar and Masson pine plantations—with respect to their insect diversity, pest problems and pest management measures. 相似文献
12.
Smith PG 《Environmental management》2007,39(3):338-352
Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28
urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and
natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land
use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent
surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small
(<20 g) and insectivorous species. Natural area size (ha) was related to higher species richness, lower evenness and higher
percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher
number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with
higher species richness. Common, resident bird species dominated small areas (<6.5 ha), while less common non-residents increased
with area, indicative of a nested distribution. Areas at least 6.5 ha and more generally >20 ha start to support some area-sensitive
species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and <5% alien
species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along
a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation
in urban landscapes. 相似文献
13.
The Spatio-Temporal Dynamic Pattern of Rural Residential Land in China in the 1990s Using Landsat TM Images and GIS 总被引:2,自引:0,他引:2
Through interpreting Landsat TM images, this study analyzes the spatial distribution of rural settlements in China in 2000.
It calculates rural residential land percentage for every 1-km2 cell. The entire country is divided into 33 regions to investigate the spatio-temporal dynamic patterns of rural residential
land during the 1990s. According to the remote sensing survey, the rural residential land increased by 7.88 × 105 ha in the 1990s. The increment of rural residential land was 0.55 million ha in 1990–1995 and 0.23 million ha in 1995–2000.
In 1990–1995, rural residential land increased dramatically in the eastern regions such as the Yangtze River Delta, Pearl
River Delta, and North China Plain, accounting for 80.80% of the national growth; the expansion in the western regions was
much more moderate. In 1995–2000, the expansion of rural residential land in eastern regions slowed, accounting for only 58.54%
of the increase at the national level, whereas the expansion in the western regions accelerated. Rapid rural residential development
resulted from increasing home construction and the limited control on rural land. The great regional disparity reflected the
regional economic development and land-use policy change. Our finding shows that nearly 60% of the rural residential area
came from cropland. 相似文献
14.
This article begins by summarizing the importance of the forestry sector in the Philippine economy It provides an overview of the multiplicity of Philippine governmental institutions involved in forestry in 1982 Then it discusses forestry laws in the country and concludes by examining fifteen critical forest policy issues: sustained yield management; area-specific logging bans; increased use of wood wastes; revision of forest charges; unprocessed log export ban; rationalization of the forest industry, acceleration of reforestation; protection of watersheds; recognition of the social dimensions of slash- and-burn agriculture; fuelwood supply; public land classification for forestry and agriculture, development of plantations for dendrothermal electricity; multiple-use management; preservation of mangrove areas, and improvements in administration and implementation.Research for this paper was supported by the East-West Center Environment and Policy Institute. The author would like to acknowledge the assistance of the Natural Resources Management Center of the Philippine Ministry of Natural Resources. 相似文献
15.
Nepal's economic activity is dominated by agriculture. The volume of exports is small. About a quarter of the foreign exchange earned from export is required to cover costs of imported fossil fuels. Fossil fuels supply less than 7% of total energy consumption. More than 90% of primary energy consumption is supplied by biomass resources, and forests are the major source of biomass. The sustainable fuelwood yield of forest is far less than the total consumption, which has caused severe forest denudation. Consumption of crop residues and animal dung for fuel are increasing because of fuelwood shortage. The paper outlines the consequences of biomass consumption in Nepal and past efforts at biomass resources management and indicates their effectiveness. A few major practical policy measures have been suggested to correct the situation. The experiences and measures for biomass resources management explained in this paper are expected to be useful to other countries facing a similar situation. 相似文献
16.
17.
Comparative studies on plant species richness, endemism, floristic composition, and structure between protected and unprotected
forests are few in the Eastern Arc Mountains, one of the most biodiverse ecosystems in Africa. This study from one mountain
range, the East Usambaras, examines floristic and structural tree data from 41–0.5 ha plots in four types of Eastern Arc forest:
active agroforests, recently abandoned agroforests, mature secondary forest, and natural forest. Active agroforests had significantly
lower tree species richness, endemic species richness, and stand density compared to natural and mature secondary forest.
Recently abandoned agroforests contained a higher tree species richness, density, and tree height than active agroforests.
Active and abandoned agroforests were dominated by an invasive tree, Maesopsis eminii. This tree species makes up a large percentage of the stems in active agroforests (26%), recently abandoned agroforests (32%),
and in the canopy of mature secondary forests ∼ 30 years post logging (30%). Through time the increasing dominance of this
non-native tree in active agroforests is a concern when considering the role of agroforests in a landscape scale conservation
strategy. 相似文献
18.
Land use change and population growth in the Morobe Province of Papua New Guinea between 1975 and 2000 总被引:1,自引:0,他引:1
The relation between human population growth and land use change is much debated. Here we present a case study from Papua New Guinea where the population has increased from 2.3 million in 1975 to 5.2 million in 2000. Since 85% of the population relies on subsistence agriculture, population growth affects agricultural land use. We assessed land use change in the Morobe province (33,933 km2) using topographic maps of 1975 and Landsat TM images of 1990 and 2000. Between 1975 and 2000, agricultural land use increased by 58% and population grew by 99%. Most new agricultural land was taken from primary forest and the forest area decreased from 9.8 ha person(-1) in 1975 to 4.4 ha person(-1) in 2000. Total population change and total land use change were strongly correlated. Most of the agricultural land use change occurred on Inceptisols in areas with high rainfall (>2500 mm year(-1)) on moderate to very steep slopes (10-56%). Agricultural land use changes in logged-over areas were in the vicinity of populated places (villages), and in close proximity to road access. There was considerable variation between the districts but districts with higher population growth also had larger increases in agricultural areas. It is concluded that in the absence of improved farming systems the current trend of increased agriculture with rapid population growth is likely to continue. 相似文献
19.
The Cache River of southernmost Illinois is used as a case study for developing and demonstrating an approach to quantitatively
link (1) national agricultural policy and global agricultural markets, (2) landowner's decisions on land use, (3) spatial
patterns of land use at a watershed scale, and (4) hydrologic impacts, thus providing a basis to predict, under a certain
set of circumstances, the environmental consequences of economic and political decisions made at larger spatial scales. The
heart of the analysis is an estimation, using logistic regression, of the affect of crop prices and Conservation Reserve Program
(CRP) rental rates on farmland owner's decisions whether to reenroll in the CRP or return to crop production. This analysis
shows that reasonable ranges for crop prices (80%–150% of 1985–1995 values) and CRP rental rates (0–125% of 1985–1995 rates)
result in a range of 3%–92% of CRP lands being returned to crop production, with crop prices having a slightly greater effect
than CRP rental rates. Four crop price/CRP rental rate scenarios are used to display resulting land-use patterns, and their
effect on sediment loads, a critical environmental quality parameter in this case, using the agricultural non point source
(AGNPS) model. These scenarios demonstrate the importance of spatial pattern of land uses on hydrological and ecological processes
within watersheds. The approach developed can be adapted for use by local governments and watershed associations whose goals
are to improve watershed resources and environmental quality. 相似文献
20.
Landscapes of Protection: Forest Change and Fragmentation in Northern West Bengal,India 总被引:1,自引:0,他引:1
Harini Nagendra Somajita Paul Sajid Pareeth Sugato Dutt 《Environmental management》2009,44(5):853-864
In the tropics and sub-tropics, where high levels of biodiversity co-exist with some of the greatest levels of population
density, achieving complete exclusion in protected area contexts has proved close to impossible. There is a clear need to
recognize that parks are significantly impacted by human–environment interactions in the larger landscape within which they
are embedded, and to move the frontier of research beyond the boundaries of protected areas in order to examine larger landscapes
where multiple forms of ownership and access are embedded. This research evaluates forest change and fragmentation between
1990 and 2000, in a landscape surrounding the Mahananda Wildlife Sanctuary in the Indian state of West Bengal. This protected
forest is bounded to the south by a less intensively protected area, the Baikunthapur Reserve Forest, and surrounded by a
mosaic of unprotected, largely private land holdings. Results indicate differences in the extent and spatial pattern of forest
cover change in these three zones, corresponding to different levels of government protection, access and monitoring. The
two protected areas experience a trend toward forest regrowth, relating to the cessation of commercial logging by park management
during this period. Yet, there is still substantial clearing toward peripheral areas that are well connected to illegal timber
markets by transportation networks. The surrounding landscape, although experiencing some forest regrowth within less intensively
cultivated tea plantations, is also becoming increasingly fragmented, with potentially critical impacts on the maintenance
of effective wildlife corridors in this ecologically critical region. 相似文献