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51.
Contributing to the debate on the causes of Himalayan environmental degradation, the status and management of four watersheds
in the Upper Pokhara Valley were studied using information available from land use analysis, household surveys conducted in
1989 and 1992, deliberations held with villagers, and field observations. Accordingly, areas under forests and grazing lands
were found being depleted at relatively high rates between 1957 and 1978 due mainly to the government policy of increasing
national revenue by expansion of agricultural lands, nationalization of forests, steadily growing population, and dwindling
household economy. Despite the steady growth of population, this process had remarkably slackened since 1978, owing primarily
to remaining forests being located in very, steep slopes and implementation of the community forestry program. Forests with
relatively sparase tree density, however, and grazing lands in the vicinity of settlements have been undergoing degradation
due to fuelwood and fodder collection and livestock grazing. In many instances, this is aggravated by weak resource management
institutions. Being particularly aware of the economic implication of land degradation, farmers have adopted assorted land
management practices. Still a substantial proportion ofbari lands in the hill slopes is vulnerable to accelerating degradation, as the arable cropping system is being practiced there
as well. The perpetuation of the local subsistence economy is certain to lead, to a further deterioration of the socioeconomic
and environmental conditions of watersheds. To facilitate environmental conservation and ecorestructuring for sustainable
development, a broad watershed management strategy is outlined with focus on alleviating pressure on natural resources. 相似文献
52.
Enhancing Conservation,Ecosystem Services,and Local Livelihoods through a Wildlife Premium Mechanism
Eric Dinerstein Keshav Varma Eric Wikramanayake George Powell Susan Lumpkin Robin Naidoo Mike Korchinsky Christian Del Valle Shubash Lohani John Seidensticker Dirk Joldersma Thomas Lovejoy Andrey Kushlin 《Conservation biology》2013,27(1):14-23
We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance‐based payment scheme would allow stakeholders in lower‐income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co‐occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long‐term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here. Mejora de la Conservación, Servicios del Ecosistema y Calidad de Vida Local Mediante un Mecanismo de Compensación de Vida Silvestre 相似文献
53.
Jeffrey Hoelle 《Journal of Land Use Science》2018,13(1-2):166-181
This study analyzes the distribution of cultural values associated with forest and non-forest landscapes among stakeholder groups shaping land use and land cover change (LULCC) in an agricultural/forest frontier in the western Brazilian Amazon. The study addresses theoretical and methodological obstacles to the integration of cultural data and social science research into the study of LULCC, providing a simple, systematic, and more accurate way of understanding this missing feature of land change. The findings offer insights on elusive cultural features that influence how diverse actors make land use decisions and respond to drivers, and can thus contribute to enhancing the predictive capacity of land change research. 相似文献
54.
Land Degradation: A Challenge to Ethiopia 总被引:11,自引:3,他引:8
Taddese G 《Environmental management》2001,27(6):815-824
Land degradation is a great threat for the future and it requires great effort and resources to ameliorate. The major causes
of land degradation in Ethiopia are the rapid population increase, severe soil loss, deforestation, low vegetative cover and
unbalanced crop and livestock production. Inappropriate land-use systems and land-tenure policies enhance desertification
and loss of agrobiodiversity. Utilization of dung and crop residues for fuel and other uses disturbs the sustainability of
land resources. The supply of inputs such as fertilizer, farm machinery and credits are very low. The balance between crop,
livestock, and forest production is disturbed, and the farmer is forced to put more land into crop production. For environmentally
and socially sustainable development, there is an urgent need to promote awareness and understanding of the interdependence
of natural, socioeconomic, and political systems at local and national levels. Understanding the current status and causes
of land degradation is very important. This paper reveals the important elements of land degradation in Ethiopia and suggests
possible solutions that may help to ameliorate the situation. 相似文献
55.
B. Bowonder 《Environmental management》1986,10(5):599-609
Environmental problems are becoming serious in India because of the interacting effects of increasing population density, industrialization and urbanization, and poor environmental management practices. Unless stringent regulatory measures are taken, environmental systems will be irreversibly degraded. Lack of political commitment, lack of a comprehensive environmental policy, poor environmental awareness, functional fragmentation of the public administration system, poor mass media concern, and prevalence of poverty are some of the major factors responsible for increasing the severity of the problems. Environmental problems in India are highly complex, and management procedures have to be developed to achieve coordination between various functional departments, and for this, political leaders have to be convinced of the need to initiate environmental protection measures. 相似文献
56.
Joanne Heckman 《Environmental management》1985,9(2):141-149
The Cape Verde Islands originally supported a limited island ecology which, since the arrival of settlers 500 years ago, has been steadily altered or destroyed. Today, deforestation and overfarming, combined with the natural conditions of aridity and strong winds, have rendered the islands barren and eroded. The current government of the Republic of Cape Verde is attempting to alter traditional attitudes and customs of environmental neglect and mismanagement, while at the same time striving to restore or create self-sustaining ecosystems. The introduction of plants, animals, and physical structures enhancing soil and water conservation may create a more viable total ecosystem than existed before humans arrived. 相似文献
57.
This paper describes the relevant text of the Kyoto Protocol and its implications for land-use change and forestry (LUCF) activities and addresses some of the technical issues that merit further consideration and clarification before the treaty comes into force. Although the phrasing of the Protocol is sometimes ambiguous and the opportunities limited, the Protocol does provide for some selected forest-related activities to be used to meet national commitments for the reduction of greenhouse gas emissions. To implement the forest-related portions of the Protocol, most importantly: (1) a clear definition for the word ‘reforestation' is required, (2) contradictory wording in Article 3.3 needs to be clarified to establish how credits are to be measured, (3) further thought should be given to the sentence in Article 3.7 which provides that countries with a net carbon sink in LUCF in 1990 cannot include emissions from land-use change in their 1990 baseline, whereas countries with a net carbon source in LUCF can include those emissions in their 1990 baseline, (4) the rules and baseline issues for joint implementation and the clean development mechanism need to be clarified and (5) inclusion of additional forest management activities needs to be considered. 相似文献
58.
N. Farella R. Davidson M. Lucotte S. Daigle 《Agriculture, ecosystems & environment》2007,120(2-4):449-462
In the Brazilian Amazon, colonization is modifying the landscape at an exceedingly fast pace. Recently established households practice slash-and-burn agriculture and participate in the overall deforestation of the Amazon. Near the Transamazon highway, these family agricultural practices are the main cause of deforestation. The study presented here is oriented toward a better understanding of the impacts of farming practices on soil chemical composition. This study used a sampling design based on soil samples taken on farm plots, which had been submitted to a wide range of spatial and temporal sequential land-uses, including soils that were only recently denuded. The data shows that soil responses (organic matter (OM) content, fertility and mercury (Hg) retention) to these varied land-uses were relatively similar, suggesting that the most important event determining the responses was deforestation itself. This is well illustrated by the Hg content of soils, which changed immediately after deforestation and then only slightly thereafter. This phenomenon could also be seen in the base cation (calcium (Ca), potassium (K) and magnesium (Mg)) content which rose drastically after deforestation and tended to stay high for a period up to 10 years of cropping and pasture. This lasting cation rise is reflected by ammonium (NH4) displacement from surface soils. Indeed, inorganic nitrogen (N) is the most important nutrient loss upon deforestation. Nonetheless, when time spent in fallow was greater than 15 years, base cations (Ca, Mg, K), available N and phosphorus (P) contents tended to go back to initial forest soil values and in some cases to exceed them. Soil type was seen to mediate responses to land-use. Clay-sandy soils showed a lower content of available N and carbon (C) than clayey soils at the soil surface, a difference that was accentuated by deforestation. Conversely, the higher initial content of Hg in clayey soils was associated with a more important Hg loss from the soil's surface. By shedding light on the consequences of family practices for OM, nutrient status and Hg depletion, this paper gives a new perspective on soil responses to agricultural practices. These conclusions need to be addressed in a strategy plan to limit family land-use impacts on soils and the surrounding ecosystems. Recommendations for more sustainable land uses are proposed based on what has been learned about soil responses to local agricultural practices. 相似文献
59.
From 1935 to 2000, the net open water area of Inle Lake in Central Shan State, Myanmar decreased from 69.10 to 46.69 km2, a loss of 32.4% during this 65-year period. Local beliefs are that losses in lake area have been even greater within the
last 100–200 years. Various activities, including timber removal, shifting agriculture in the uplands by various ethnic groups,
and unsustainable cultivation practices on the low- and mid-level hillslopes around the lake, have been blamed for both historical
and ongoing sedimentation. We take issue with attributing loss of lake area to these activities, and propose instead that
ongoing “in-lake” and “near-lake” agricultural practices are the main sources of contemporary sediment and loss of open water
area. About 93% (i.e., 20.84 km2) of the recent loss in open water area of the lake is due to the development of floating garden agriculture, largely along
the west side of the lake. Direct environmental impacts associated with this practice and with other agriculture activities
within the wetlands and margins of the lake include sedimentation, eutrophication, and pollution. Whilst the sustainability
of hillslope agriculture and past forestry practices can indeed be questioned, a more urgent need is to address these "in-lake"
and "near-lake" practices. 相似文献
60.
To find a principal component (PC) that quantifies the degree of soil degradation, we analyzed various physicochemical characteristics of soils over a land degradation gradient related to aboveground vegetation in the Sakacrat Environmental Research Station (SERS), Thailand. The aboveground vegetative types representing the degradation gradient were bare ground (BG, highly degraded), dry dipterocarp forest (DDF, moderately disturbed) and dry evergreen forest (DEF, the original vegetation). Soils under these vegetative types were sampled in February (dry season). March just after temporal precipitation) and June (rainy season) 2001. Through the period of this research, the degradation was consistently explained by sandy texture, high bulk density, lower pH, high exchangeable acidity, poor mineral and organic nutrients and dryness. Principal component analysis (PCA) was applied to determine significant principal components (PCs) that clarify the differences in soil properties between the vegetative types and between the timing of soil sampling. The PC loadings suggested that the first PC was the component that indicates total fertility of soil in the site, while the fifth PC indicates the dry to wet seasonal transition. The first PC was named the total fertility component (TFC). The linear regression between the TFC score and recently proposed indexes, the soil fertility index (SFI) or the soil evaluation factor (SEF), was highly significant (p < 0.001), indicating that the SFI and the SEF are applicable to measuring total fertility of soils in the SERS. 相似文献