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Protected areas serve two objectives, biodiversity conservation and securing of ecosystem services. But the recent expansion of human activities around Cameroon’s Rumpi Hills Forest Reserve in this Era of Sustainable Development Goals is a call for concern. This study assesses land use and land cover change around the reserve and their potential impact on its sustainability. A total of 250 household surveys were conducted across 13 villages in four selected sites around the reserve in addition to 11 focus group discussions. Landsat 7 ETM (2000) and Landsat 8 OLI (2014) images and topographic maps were utilized to quantify land use and land cover change.

During the 14-year period, dense forest dropped to 90.2% while settlements increased from 744.6 to 2148.8 hectares in 2014. Also, farmlands increased by 18.25% representing a change from 9400.4 to 11117.16 hectares. Over 98% and 85% of the respondents are engaged in the cultivation of food and cash crops and are dependent on the forests for timber and non-timber forests products. Land and tree-based interventions that improve soil fertility should be promoted among smallholder farmers to ensure the sustainability of protected areas in Cameroon.  相似文献   


3.
A comparison of the management models of protected areas between China and the African south region allows reading and evaluating the similarities and differences in the use of management model as a management tool for protected areas and specifically some positive and negative features of the management approaches in these two regions. Previous to this study it verified the designation of protected areas as increasing at a faster rate than ever before, comparatively much faster now in China than southern Africa regions. With the aim of evaluating similarities and differences in the use of management model as a management tool for protected areas in China and southern Africa Region, both qualitative and quantitative data were collected. Qualitative data were mainly from policy documents, scientific articles and magazine reports, whereas quantitative (secondary data) statistical data from International Union for Conservation of Nature Resources (IUCN) and World Database on Protected Areas (WDPA). In view of the data sources above, the study found that in China all the protected areas are state owned whilst in southern Africa regions there are some protected areas that are privately owned; also that the models or typology of governance applied are successful for the fact that they both combine co-management or collaborative management, community-conserved areas and private protected areas that are subject to greater success and can help design planning and management than those who use exclusively government management. To this, the study concluded that the use of management model is influenced by the type of governance a country applies to its reserved areas.  相似文献   

4.
While early efforts to establish protected areas often excluded local people, modern approaches in many countries now seek to involve local communities in ways that are appropriate to the objectives for the protected area. In the Lao People's Democratic Republic (Lao PDR), a protected area management system was established in 1993. In many cases, the new protected areas had land-use conflicts with inhabitants who depended on the areas for their living. This study was undertaken in a protected area in the northwest of the Lao PDR. The primary objective was to identify and gain experiences from a feasible approach for improvement and implementation of protected area management with a positive interaction between people and the natural environment. An integrated land-use planning approach was adopted. It included participatory methods for data capture and analysis, including the use of a simple simulation model, the ‘Area Production Model’ (APM) aiming at evaluating different options for land use and primary production. The outcome of the study was positive in the sense that this integrated land-use planning approach was found to be well adapted to the needs of the protected area management system.  相似文献   

5.
ABSTRACT

Many forest reserves in Bangladesh have been converted to protected areas (PAs) to conserve the forests resources from further depletion. This study has investigated if such initiatives have improved the state of biodiversity of these PAs amid tremendous anthropogenic pressure on forest resources. We have assessed the phytosociological attributes of the PAs in the country through a case study at Kaptai National Park (KNP) and compared the attributes with those of the adjacent areas and of the tropical forests across the world. We have identified 52 species belonging to 45 genera and 28 families. The most dominant species in KNP was Dipterocarpus spp. and the adjacent area was dominated by Tectona grandis. Unexpectedly, the Shannon-Wiener index of KNP has dropped down from 2.98 in 2000 to 0.90 in 2014. However, in terms of relative density, relative dominance, and relative frequency, KNP was better than the adjacent areas. In contrast, the mean Shannon-Wiener index in KNP (0.90) was smaller than that in the tropical countries (2.99). We recommend strengthening effective comanagement of PAs and enabling nonforestry income generation activities for the forest-dependent people so that the biodiversity of the PAs can be enriched while people’s livelihoods are ensured.  相似文献   

6.
The 170 samples obtained from ligneous investigation in Barkoissi, Galangashi and Oti-Keran protected areas (northern -  相似文献   

7.
Changing land uses and cover types influence vegetation composition and health, so understanding the effects of these changes on net primary production (NPP) provides an important tool for monitoring ecosystem responses to environmental change. Using remote-sensing images and precipitation, temperature, and total solar radiation data from 1978, 1987, 2000, and 2005, and a light utilization efficiency model, we studied the effects of changes in these parameters and land use and cover types on NPP in China's Yongding River basin. We determined the NDVI of vegetation in the basin, and used these results to estimate the NPP of vegetation in the basin and the influence of land use and cover type changes on NPP under two climate scenarios: one in which the precipitation and temperature of the previous period remain unchanged into the following period, that is, use the climate in 1978, 1987 and 2000 to analyze NPP data in 1987, 2000 and 2005 respectively, and another in which both parameters remain constant at their 1978 values throughout the study period. With the climate unchanged from the former period, NPP in 1987 decreased compared with the 1978 value by 20–50 gC/m2, and then increased by more than 40 gC/m2 in western and central parts of the basin from 1987 to 2000. From 2000 to 2005, NPP decreased in the northwestern, northern, and eastern parts of the basin. With climate unchanged from 1978 to 2005, NPP increased from 1987 to 2000 by from 10 to 30 gC/m2 in most areas. From 2000 to 2005, some farmland in western and northwestern parts of the basin and some forest land were converted into grassland, decreasing NPP by 40–50 gC/m2.  相似文献   

8.
本研究以清水县为研究区域,以1979年和2008年该区的TM数据为遥感数据源,在遥感数字图像处理系统和GIS支持下,通过提取NDVI值以及NDVI与植被覆盖度之间的关系,对该县植被覆盖变化进行了研究。研究结果表明:1979~2008年清水县整体植被覆盖有所增加,植被指数在138以上的面积从1979年的52488.13hm2增加到2008年的117603.38hm2,净增65115.25hm2,占全县面积的33.80%;低盖度植被类型面积大大减少,其中,Ⅴ级植被面积减少了73780.25hm2,占全县总面积的34.22%,高盖度植被面积增加,其中,Ⅰ级植被增长了33798.07hm2,占全县总面积的17.54%,Ⅱ级、Ⅲ级植被面积均有不同程度的增加,植被盖度等级未变化的面积为62954.75hm2,占全县总面积的32.68%;植被退化面积为11768.25hm2,而植被好转面积多达117926.75hm2,是退化面积的10.02倍。通过综合治理,清水县生态环境得到大大改善。  相似文献   

9.
The Beaver Hills region of central Alberta is located at the interface of the southern boreal mixedwood forest and the aspen parkland, an area now dominated by agriculture, urban and industrial development. Increasing anthropogenic land cover will eventually isolate remaining natural habitats currently protected in parks and reserves. This paper analyzes land cover and land cover change (LCC) in the Beaver Hills moraine and surrounding areas using a structured hierarchical satellite imagery classification applied to Landsat Multi Spectral Scanner and Thematic Mapper from 1977, 1987, and 1998. Our goal was to quantify deforestation and habitat fragmentation trends and then discuss how this information could be used to develop a conservation approach that will protect current areas against further habitat loss. We found that the rate of deforestation in the lands surrounding the moraine was similar to the broad trend at the southern periphery of the Canadian boreal forest region: annual rate of change in forest cover was −0.82%/year. However, in the Beaver Hills there was a net gain of +0.61%/year, due to regeneration of low quality agricultural lands. All fragmentation indices used indicated an increase in forest fragmentation. We designed a network of protected areas and remaining large forest patches, based on the UNESCO-MAB biosphere model. Our results underline concerns regarding the increasing isolation of national parks and biological reserves in Canada.  相似文献   

10.
Land use/land cover change is an important driver of global change and changes in carbon stocks. Estimating the changes in carbon stocks due to tropical deforestation has been difficult, mainly because of uncertainties in estimating deforestation rates and the biomass in the forest that have been cut. In this study, we combined detailed land-use change over a 27-year period based on satellite images and forest inventory data to estimate changes in biomass carbon stocks in the Xishuangbanna prefecture (1.9 million ha) of China. Xishuangbanna is located in southwestern China in the upper watershed of the Mekong River, and the major forest types are tropical seasonal rain forest, mountain rain forest, and subtropical evergreen broadleaf forest. In the past when the region was completely forested the total biomass carbon would have been approximately 212.65 ± 8.75 Tg C. By 1976 forest cover had been reduced to 70%, and in addition many forests had been degraded resulting in a large decrease in the total biomass carbon stocks (86.97 ± 3.70 Tg C). From 1976 to 2003, the mean deforestation rate was 13 722 ha year−1 (1.12%), and this resulted in the loss of 370,494 ha of forest, and by 2003 total biomass carbon stocks had been reduced to 80.85 ± 2.64 Tg C. The annual carbon emissions due to land-use change, mainly forest conversion to agriculture and rubber plantations, were 0.37 ± 0.03 Tg C year−1 between 1976 and 1988 and 0.13 ± 0.04 Tg C year−1 between 1988 and 2003. During the next 20 years, if rubber plantations expand into forests outside of reserves, shrublands, grasslands, and shifting cultivation below 1500 m the total biomass carbon stocks of Xishuangbanna will decrease to 76.45 ± 1.49 Tg C in 2023. This would reflect a loss of 4.13 ± 1.14 Tg C between 2003 and 2023, or an annual loss of 0.21 ± 0.06 Tg C year−1. Alternatively, if rubber plantations only expand into areas of shifting cultivation below 1500 m, and all areas presently in shrublands and grasslands are allowed to recover into secondary forests, total biomass carbon stock of the region would increase to 92.65 ± 3.80 Tg C in 2023. Under this scenario, the growth of existing forests and the expansion of new forests would result in a net sequestration of 0.60 ± 0.06 Tg C year−1. This study demonstrates that the uncertainty of biomass estimates can be greatly reduced if detailed land-use analyses are combined with forest inventory data, and that slight changes in future land-use practices can have large implications for carbon fluxes.  相似文献   

11.
Protected areas are necessary for the conservation and enhancement of biodiversity.Wildfires are major threats to forests and other natural areas,because they may cause irreversible damages.The aim of this study was to analyze the perspective of experts(N=284),from six countries of the Black Sea,on the current status and problems of protected areas and wildfires.Understanding their points of view could enhance future management on these issues in the region.Data collection was carried out for 9 months,using a web-based questionnaire.Wildfires were perceived as a serious problem in Turkey,Armenia and Greece but as a substantially less serious problem in Romania,Ukraine and Moldova.In Greece,Armenia,and especially Ukraine,the current designated protected areas are considered sufficient to maintain biodiversity,while in Romania,Turkey,and especially Moldova,more areas should be designated as protected.A major need in all countries(except for Turkey)is the increased use of information and communication technologies for both wildfire suppression and protected area management.Experts were divided on whether wildfire suppression and management of protected areas are interconnected.However,there is growing awareness of the adverse impacts of climate change in protected areas and the frequency of wildfires in the future.The most frequently suggested measures to alleviate these impacts were:changes in forest management and increasing public awareness for wildfire suppression,along with changes in forest management and increased staff training to enhance protected area conservation.  相似文献   

12.
During the past few decades, China has implemented several large-scale forestation programs that have increased forest cover from 16.0% in the 1980s to 20.4% in 2009. In northern China, water is the most sensitive and limiting ecological factor. Understanding the dynamic interactions between forest ecosystems and water in different regions is essential for maximizing forest ecosystem services. We examined forest cover and runoff relationships in northern China using published data from a variety of sources. In the Loess Plateau region, forest cover is not correlated with annual precipitation (r = 0.08, p > 0.05) at micro (<50 km2) and meso scales (50-1000 km2), while they are positively correlated at macro (>1000 km2) scale (r = 0.77, p < 0.05). Moreover, forest cover is negatively correlated with the runoff coefficient (r = −0.64, p < 0.05). In Northwest China, natural forest distribution is highly correlated with annual precipitation (r = 0.48, p < 0.05) but not with the runoff coefficient (r = −0.09, p > 0.05). In Northeast China, we found a positive relationship between forest cover and the runoff coefficient (r = 0.77, p < 0.05), but the correlation between forest cover and precipitation was not significant (r = 0.28, p > 0.05). The multiple stepwise regression analysis indicated that runoff was influenced by altitude, annual precipitation, forest cover, and PET (potential evapotranspiration) in Northeast China. We concluded that geographic differences could mask the true role of forests in the partitioning of rainfall into runoff and evapotranspiration (ET) in a catchment. In determining the forest-water relationship, one must consider climatic controls on ET in addition to forest cover. Forests could potentially enhance the complementary relationship between ET and PET. Therefore, a greater amount of ET in forested areas may decrease the PET on a regional scale.  相似文献   

13.
Seabuckthorn (Hippophae rhamnoides) planting areas in the three northern areas (north, northeast and northwest) of China are divided into five planting zones: the semi-humid forest prairie climate zone for ecological and economic types of seabuckthorn plantations in the southern part of the Loess Plateau; the semi-arid steppe climate zone for similar types of plantations in the central part of the Loess Plateau; the arid desert steppe climate zone for ecological type of seabuckthorn plantations in the northern part of the Loess Plateau; the semi-arid and semi-humid steppe climate zone again for ecological and economic types of plantations in northern Hebei and western Liaoning and the cold humid steppe climate zone for economic types of plantations in the northern part of northeast China. The aim of this demarcation is to avoid a random introduction of seabuckthorn. In each of the five zones, objectives should be set and suitable seabuckthorn species, subspecies and varieties should be planted according to site conditions, seed sources and methods of tree breeding. The cultivation centers, bases, stations, or units should be established and successful models of seedling and planting methods should be encouraged. The principle of matching trees with suitable site conditions and adjusting measures to local conditions should be practiced. From a strategic viewpoint of solving ecological and economic problems of seabuckthorn development in the three northern areas, every seabuckthorn center must have its own germplasm nursery, standard plantation for popularizing, excellent seed and seedling nurseries and sufficient afforestation areas for demonstration and propaganda purposes. These measures would improve the ecological environment and promote economic and social development in the three northern areas of China.  相似文献   

14.
Protected areas in tourist hot spots are under increasing pressure from growing commercial tourism and wild plants utilization. However, few studies of tourists’ behaviors and attitudes towards eating wild edible plants in protected areas have been conducted. This study presents the results of an investigation conducted on 202 tourists and 334 households in the Qinling Mountains in China to examine relationships between harvest/eating wild edible plants and the tourism experience. According to the results, there is a high demand for wild edible plants by tourists and local people because of traditions and the desire for green food. Tourists with a higher level of education, maturity, or environmental awareness eat wild edible plants to a lesser extent. However, higher income may encourage greater utilization of wildland resources. Analytical results indicate significant inconsistency between tourists’ perceptions of wildland resource conservation and their actual behavior. Besides, the respondents perceive a low level of environmental responsibility in spite of their stated environmental awareness. This study highlights the need to fulfill ecological responsibility when tourism occurs in protected areas to achieve species conservation and sustainability.  相似文献   

15.
Land use plays a much more important role than other factors, such as climate, soil properties, topographic features, vegetation coverage, human activities and others, in affecting soil erosion and sediment discharge. In order to understand the effects of changes in land use on sediment discharge and to provide a theoretical basis for land use planning, management and ecological restoration, we used the controlled Qiaozidong watershed and the uncontrolled Qiaozixi watershed in the third sub-region of the Loess Plateau as examples and analyzed the effects of land use and land cover on the discharge of sediments. The results show that the impact of land use and land cover on the annual amount of sediment discharge is significant. Compared with the uncontrolled watershed during similar periods, the amount of sediment discharged from the controlled watershed was reduced by 44%, 75% and 86%, respectively, in wet, normal and dry years. In the controlled watershed, compared with the period from 1986 to 1994, the amount of sediments discharged was less during the period from 1995 to 2004. The impact of land use and land cover on sediment discharge demonstrated characteristics of seasonal fluctuation. The effects of sediment reduction in the controlled watershed were greater than those in the uncontrolled watershed in May and September. In the controlled watershed, the reduction effect coincided with the distribution of rainfall. The amount of discharged flood sediments is closely correlated with rainfall, rainfall intensity in a 60 min period and the volume of flood. The rainstorm-runoff process and the rainstorm-sediment discharge process demonstrate that land cover has a strong regulatory and control function in the flood process and sediment discharge in rainstorms. For the controlled watershed, given the same precipitation frequency distribution, the average amount of sediment discharged during the land use period from 1995 to 2004 was less than that during the earlier land use period from 1986 to 1994 under every recurrent period. __________ Translated from Journal of Beijing Forestry University, 2007, 29(6): 115–122 [译自: 北京林业大学学报]  相似文献   

16.
Contests over scarce and shared natural resources continue to headline conflicts across the world’s geographic regions. The transfrontier conservation areas (TFCAs) concept gained widespread acceptance as one of the promising conflict management strategies. However, following the establishment of TFCAs by various countries, questions about their contribution to conflict management and resolution are emerging. Motivated by the institutional work concept, the contribution of TFCAs and their institutional framework for peace and cooperation efforts was assessed. Using field experience and the archival method, 131 journal articles, books and reports on natural resources and conflict management were reviewed between 2010 and 2016. The review process focused mainly, but not limited to TFCAs and their institutional frameworks in the Southern African Development Community (SADC). Findings indicate that TFCAs and their institutional frameworks are relevant to peace and cooperation efforts in SADC provided the stakeholders at various levels are committed to the actions agreed upon. However, making conclusive statements without further comprehensive studies on the contribution of other peace-promoting interventions within the SADC region besides TFCAs may be ill conceived. Governments and other key stakeholders are recommended to further harmonize conservation legislation, institutions and management practices to promote cooperation at the local and regional level.  相似文献   

17.
In many parts of Central America long fallow periods are no longer feasible due to increasing land pressures. Farmers in northern Honduras have developed and diffused from farmer-to-farmer a maize cropping system using velvetbean (Mucuna spp.) as a short-term fallow. High total annual rainfall in a bimodal distribution is favorable to the system because it allows the completion of two rainfed cropping cycles annually. The first season is dedicated to the production of the mucuna crop and the second season is dedicated to maize. Soil pH and exchangeable Ca were not reduced during a 15-year period of continuous mucuna use. Soil organic matter, infiltration, and porosity increased with continuous mucuna use. Maize yields in fields with continuous rotation of mucuna were on average double those obtained without mucuna. The mucuna system was more profitable than the existing alternative bush-fallow system due to higher returns to land and labor resulting from higher yields, lower weeding and land preparation costs, and reduced risk of drought stress. The relative profitability of the mucuna system was also enhanced by seasonally high maize prices during the second season when maize is harvested in the mucuna system. Relatively easy access to land through inexpensive land ownership and land rental markets has made it possible for even small-scale farmers to dedicate land to the mucuna system. Land-use intensity is increasing in the region, however, as land is converted to pastures for cattle production. The opportunity costs of keeping land in the mucuna system, while also accessing land for first-season maize and other crops, are also increasing. These experiences remind us that a viable livelihood is the primary factor in farmers' decision making about adoption particular components of farming systems.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

18.
Provision of accurate carbon (C) measurements and analysis are critical components in quantification of C stocks. The objectives of this review were to (1) compile and synthesise current knowledge of available methods for C stock estimation, (2) examine socio-economic drivers of land-use and land-cover change and their influence on woodland C stocks and (3) identify gaps of knowledge and methodological inadequacies in understanding factors affecting C stocks of major C pools for miombo woodlands of southern Africa. The review shows that quantification of forest C is a challenging task, mainly associated with knowledge gaps and methodological challenges. This has brought about a high level of uncertainty and inconsistencies, mainly due to the accounting methods applied. Furthermore, it is necessary to consider the inherent spatial heterogeneity of the landscape and stand density in order to ensure development of accurate C estimation methodologies when developing C models. Ultimately, developing widely applicable biomass models for southern Africa will require detailed assessments, including different aspects of wood C fractions. It is evident from the review that a comprehensive understanding of socio-economic drivers of land-use and land-cover change is necessary to ensure better-informed sustainable forest management policy direction, strategy and practice to deliver C and livelihood options.  相似文献   

19.
松华坝水库水质下降的原因主要是库区村庄生产生活污水未经处理直接排入水库所致,依据对松华坝水源保护区移民搬迁后的土地调查结果,提出了移民搬迁土地生态恢复、水源涵养林和水土保持林营造、防护林带建设等生态恢复措施以及生态环境保护措施。  相似文献   

20.
We mapped the forest cover of Khadimnagar National Park (KNP) of Sylhet Forest Division and estimated forest change over a period of 22 years (1988-2010) using Landsat TM images and other GIS data. Supervised classification and Normalized Difference Vegetation Index (NDVI) image classification approaches were applied to the images to produce three cover classes, viz. dense forest, medium dense forest, and bare land. The change map was produced by differencing classified imageries of 1988 and 2010 as before image and after image, respectively, in ERDAS IMAGINE. Error matrix and kappa statistics were used to assess the accuracy of the produced maps. Overall map accuracies resulting from supervised classification of 1988 and 2010 imageries were 84.6% (Kappa 0.75) and 87.5% (Kappa 0.80), respec- tively. Forest cover statistics resulting from supervised classification showed that dense forest and bare land declined from 526 ha (67%) to 417 ha (59%) and 105 ha (13%) to 8 ha (1%), respectively, whereas medium dense forest increased from 155 ha (20%) to 317 ha (40%). Forest cover change statistics derived from NDVI classification showed that dense forest declined from 525 ha (67%) to 421 ha (54%) while medium dense forest increased from 253 ha (32%) to 356 ha (45%). Both supervised and NDVI classification approaches showed similar trends of forest change, i.e. decrease of dense forest and increase of medium dense forest, which indicates dense forest has been converted to medium dense forest. Area of bare land was unchanged. Illicit felling, encroachment, and settlement near forests caused the dense forest decline while short and long rotation plantations raised in various years caused the increase in area of medium dense forest. Protective measures should be undertaken to check further degradation of forest at KNP.  相似文献   

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