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1.
The condition of the semi-arid Borana rangeland in southern Ethiopia was assessed by studying different land-use systems (communal land, a government ranch and a traditional grazing reserve enclosure) and along a distance gradient (near, middle and far) from water sources. The assessment incorporated the soil, herbaceous and woody plant layers. Two methods were employed to evaluate the grass layer, viz. ecological condition index (ECI) and weighted palatability composition (WPC). The ECI on the government ranch was 21.7% and 26% greater than that of the traditional reserve and the communal land, respectively. The WPC on the government ranch was 83.3% and 48.6% greater than that of the communal area and the traditional reserve, respectively. Both ECI and WPC values were similar for all distance sites from water. Tree equivalent (TE) density, of all encroaching woody plants combined, was higher on the communal land (504 TE ha(-1)) than the government ranch (373 TE ha(-)1) and traditional grazing reserve (118 TE ha(-1)), but with no marked variations in the distance sites from water. Height class distribution of encroaching woody plants in the study areas showed the largest abundance (range: >50-100%) at the height class >0-2m. Tree equivalents per hectare of encroaching woody plants were negatively correlated (r = -0.60) with ECI and WPC and positively correlated (r=0.87) with percentage bare ground. The correlation (r = 0.50) between percentage bare ground and soil compaction was positive and low. Although the government ranch had a greater composition of highly palatable grass species than the other land uses, the rangeland was not in good condition due to severe bush encroachment. The communal land was generally in poor condition. In the traditional grazing reserve, bush encroachment was not a problem, but the productivity of the grass layer was poor when assessed on the basis of ecological and palatability merits. The negative interaction of TE density of all encroaching woody plants combined with ECI or WPC and the positive interaction with bare ground, may suggest that the abundance of these species is more critical in aggravating deterioration in grassland productivity. Therefore, the priority of any bush control program must be towards minimizing the abundance of these woody plants. 相似文献
2.
The structure and advancement of woody vegetation was studied in a semi-arid rangeland of southern Ethiopia under three land-use systems (communal land, a government ranch and a traditional grazing reserve enclosure) and along a distance gradient (near, middle and far) from water sources. A total of 54 woody plant species were identified. Based on the subjective opinions of the pastoralists, 85% of the identified woody plants have forage values to livestock. Cadaba farinsoa, Ormocarpum trichocarpum, Rhus natalensis, Acacia brevispica, Cordia gharaf and Hibiscus sparseaculeatus were reported to have fair to good palatability. Tree equivalent (TE) density of all woody plants combined was greater (P <0.01) in the government ranch (1) 188 TE ha(-1)) and the communal land (1083 TE ha(-1)) than in the traditional grazing reserve (419 TE ha(-1)), whereas this did not vary significantly (P >0.05) along the distance gradient from water. The most important encroaching woody plant species in the study areas were in descending order: Commiphora africana, Acacia drepanolobium, A. brevispica, Acacia. tortilis, Grewia tembensis and Lannea floccosa. The density of individual encroaching woody plant species along the distance gradient from water was not consistent. All encroaching woody species had the highest TE density in the communal land. The prevalence of these species followed the pattern of intensity of use within the communal grazing area. Most of the woody species had the highest abundance in the height class >0-2m regardless of land use and distance gradient from water. This study investigated the advance of severe woody encroachment in the communal and government sites as well as along the distance gradient from water. Some of the important contributing factors that can be suggested are heavy grazing pressure (in both the communal and government sites), expansion of cultivation and reduced mobility of livestock due to settlement of the pastoralists in the communal land. 相似文献
3.
The distribution and compositional pattern of the grass layer, as well as soil quality of southern Ethiopian semi-arid rangelands were examined under three land-use systems (communal land, government ranch and a traditional grazing reserve enclosure) and along a distance gradient (near, middle and far) from water sources. In total, 49 grass species were identified, 65% of which were perennials. Of the most commonly distributed highly desirable species, Chrysopogon aucheri showed the greatest frequency under the traditional grazing reserve (27.6%), and the lowest in the communal land (14.0%). The frequency of Cenchrus ciliaris was similar in all the study sites. The proportion of Lepthotrium senegalensis was low under the land-use systems (3.9%) and increased away from water sources (2.3%). Of the less desirable species, Sporobulus nervosus was extremely more abundant (<0.05) in the communal land (13.3%) than the traditional grazing reserve (3.3%) and the government ranch (1.9%). Sporobolus pyramidalis was dominant in the study sites, with similar (P>0.05) frequency percentages under the land-use systems and along the distance gradients from water. Basal cover was low and similar on all the study sites (3.3%). Concerning the soil texture, sand (71.1%) constituted the largest proportion, followed by silt (21.3%) and lastly, clay (7.7%). With regard to soil exchangeable cations, organic C and total nitrogen were generally low and did not show marked variation in all the study sites. The study showed significant differences for most of the vegetation variables between the communal land and the other land-uses. This suggested that grazing intensity was higher in the communal land and moderate in the government ranch and in the traditional grazing reserves (kallos). The lack of significant differences in most of the studied (vegetation) variables along the distance gradient from water could be ascribed to the fact that grazing disturbance has already exceeded a certain threshold of degradation. Under the present low states of soil nutrients and rainfall, cultivation is neither sustainable nor environmentally friendly and this will lead to further degradation of the soil in these marginal lands. 相似文献
4.
Institutional development for sustainable rangeland resource and ecosystem management in mountainous areas of northern Nepal 总被引:3,自引:0,他引:3
Dong S Lassoie J Shrestha KK Yan Z Sharma E Pariya D 《Journal of environmental management》2009,90(2):994-1003
Rangelands represent one of the most important natural resources in mountainous regions of northern Nepal. However, a poor understanding of the social dimensions of rangeland use has limited their proper management and sustainable development, which represent major challenges for Nepal's resource managers. Institutional development is thought to be a viable solution to this problem and may ultimately lead to improved rangeland management in Nepal. Based on this hypothesis, a study was conduced in the Rasuwa district of northern Nepal to examine the effectiveness of institutional development at the local and national levels in mitigating the problems facing sustainable rangeland management by using an institutional analysis and development (IAD) framework. The information and data were mainly collected from different stakeholders, farmers, professionals and practitioners using a toolkit of participatory rural appraisal (PRA), workshops and literature review. It can be concluded from this case study that a number of institutional development efforts are needed to promote sustainable rangeland management in this region. First, local herders represent a repository of rich indigenous knowledge essential to sustaining sound rangeland management practices; hence, indigenous practices need to be integrated into modern technologies. Second, public services and technical support are currently unavailable or inaccessible to local herders; hence, research, development and extension interventions need to be initiated for marginalized pastoral communities. Third, rangeland institutions are incomplete and ill-organized, so institutional development of various organizations is necessary for promoting sustainable rangeland management. Fourth, the policies and governance necessary for promoting rangeland management are not well-designed; hence, governance reform and policy development need to be formulated through internal and external agencies and organizations. 相似文献
5.
Effects of cattle grazing and haying on wildlife conservation at National Wildlife Refuges in the United States 总被引:1,自引:0,他引:1
Beverly I. Strassmann 《Environmental management》1987,11(1):35-44
The National Wildlife Refuge System is perhaps the most important system of federal lands for protecting wildlife in the United States. Only at refuges has wildlife conservation been legislated to have higher priority than either recreational or commercial activities. Presently, private ranchers and farmers graze cattle on 981,954 ha and harvest hay on 12,021 ha at 123 National Wildlife Refuges. US Fish and Wildlife Service policy is to permit these uses primarily when needed to benefit refuge wildlife. To evaluate the success of this policy, I surveyed grassland management practices at the 123 refuges. The survey results indicate that in fiscal year 1980 there were 374,849 animal unit months (AUMs) of cattle grazing, or 41% more than was reported by the Fish and Wildlife Service. According to managers' opinions, 86 species of wildlife are positively affected and 82 are negatively affected by refuge cattle grazing or haying. However, quantitative field studies of the effect of cattle grazing and haying on wildlife coupled with the survey data on how refuge programs are implemented suggest that these activities are impeding the goal of wildlife conservation. Particular management problems uncovered by the survey include overgrazing of riparian habitats, wildlife mortality due to collisions with cattle fences, and mowing of migratory bird habitat during the breeding season. Managers reported that they spend $919,740 administering cattle grazing and haying; thus refuge grazing and haying programs are also expensive. At any single refuge these uses occupy up to 50% of refuge funds and 55% of staff time. In light of these results, prescribed burning may be a better wildlife management option than is either cattle grazing or haying. 相似文献
6.
This paper examines the factors that affect the adoption of best management practices (BMPs) in Southern Ontario watersheds
using both qualitative and quantitative techniques. A sample of 164 farmers was analyzed and triangulated with the results
from in-depth interviews. The results suggest that farm and personal characteristics affect the adoption rate of BMPs and
there should be financial incentives in order to create an enabling environment that will encourage the adoption of BMPs. 相似文献
7.
Sebastian Chakeredza Lewis Hove Festus K. Akinnifesi Steven Franzel Oluyede C. Ajayi Gudeta Sileshi 《Natural resources forum》2007,31(4):286-296
Livestock production is an integral part of smallholder farming systems in southern Africa. While goats and sheep play some role in the smallholder farmer household economy, cattle are the predominant livestock species supplying draught power, milk, manure and meat. Production of cattle is based on range grazing. However, the nutritive value of the range is generally low depending on vegetation type and season. With the rapid increase in human population in southern Africa and the increasing need to produce staple food on a sustainable basis, smallholder farmers are increasingly encroaching onto lands formerly reserved for livestock grazing. Therefore, livestock subsisting on the range require supplementation. Conventional bought‐in supplements are expensive. Fodder trees and shrubs have been integrated within some farming systems of southern Africa as fodder banks with varying degrees of success. Work carried out in Tanzania, Malawi and Zimbabwe is reviewed to provide evidence on how the fodder tree technology has impacted on livestock production with special reference to smallholder dairy production, human food production and smallholder farmers’ income. For the wider adoption of the technology, a synopsis of the different scaling up pathways and approaches adopted by research and development agencies is presented. 相似文献
8.
In this paper, the implementation of effective waste management practices in construction projects and sites is analyzed, using data from a survey answered by 74 Spanish construction companies based in Catalonia. Most commonly implemented practices were found to be on-site cleanliness and order, correct storage of raw materials, and prioritization of the nearest authorized waste managers. The least widespread practices were the use of a mobile crusher on site, the creation of individualized drawings for each construction site, and the dissemination of the contents of the waste management plan to all workers, to help them to meet its requirements. Waste regulations for construction and demolition, and the corresponding construction waste management facilities, were designed before the recession in the Spanish construction sector. Current waste generation rates are still below predicted levels, and the infrastructure was designed for five times more waste generation. Even so, the percentage of reused and recycled waste currently amounts to 43%. Survey respondents highlighted various instruments and measures that would make the management of construction and demolition waste more sustainable. Most of the opportunities identified by construction firms are within the scope of government and related to a combined system of bonus and penalties and the establishment of environmental awareness and training programmes for all the stakeholders. Within the scope of authorized waste managers, firms suggested improvements such as the standardization of fees, a reduction of the time until the issue of waste management certificates, a higher number of inspections, and a change in the current model of a few large construction waste management facilities. This research is useful to better understand the current status of construction and demolition waste management in construction projects and sites. Thus, the results of this research will guide policy makers and relevant stakeholders such as contractors, clients, architects and engineers to achieve the EU target of recovering 70% of construction and demolition waste in 2020. In this sense, reliable information can help governments and professional associations to set future C&D waste management regulations, training programmes and dissemination tools, inspections, etc. 相似文献
9.
Over the last two decades, mining and mineral exploration companies have adopted various environmental management practices in response to society’s pressure for better environmental protection. The literature highlights a number of benefits and challenges for companies adopting environmental management practices with the Greek Mining and Mineral Industry (GMMI) facing similar issues. In order to analyze the challenges faced by the GMMI, a Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis was conducted, which examined the strengths, weaknesses, opportunities and threats faced by the industry when adopting environmental management practices. The analysis prescribes policy recommendations both for the government and industry which, if adopted, could facilitate improved environmental performance. 相似文献
10.
11.
Environmental conditions significantly affect production, but are often ignored in studies analysing productivity and efficiency leading to biased results. In this study, we examine the influence of selected environmental factors on productivity and efficiency in wheat farming in Bangladesh. Results reveal that environmental production conditions significantly affect the parameters of the production function and technical efficiency, as well as correlates of inefficiency. Controlling for environmental production conditions improves technical efficiency by 4 points (p<0.01) from 86% to 90%. Large farms are more efficient relative to small and medium sized farms (p<0.01 and 0.05), with no variation among regions. Policy implications include soil fertility improvement through soil conservation and crop rotation, improvement in managerial practices through extension services and adoption of modern technologies, promotion of education, strengthening the research-extension link, and development of new varieties that have higher yield potential and are also suitable for marginal areas. 相似文献
12.
Building future scenarios and uncovering persisting challenges of participatory forest management in Chilimo Forest, Central Ethiopia 总被引:1,自引:0,他引:1
Kassa H Campbell B Sandewall M Kebede M Tesfaye Y Dessie G Seifu A Tadesse M Garedew E Sandewall K 《Journal of environmental management》2009,90(2):1004-1013
We examined the changes in forest status and people's livelihoods through building future scenarios for Chilimo Forest in Central Ethiopia where participatory forest management (PFM) is being implemented. Participatory methods were employed to collect data, and a dynamic modeling technique was applied to explore trends over time. By integrating the more quantitative model outputs with qualitative insights, information on forests and livelihoods was summarized and returned to users, both to inform them and get feedback. A scenario of open access without PFM provides higher income benefits in the short term but not over the longer term, as compared to a scenario with PFM. Follow up meetings were organized with national decision makers to explore the possibility of new provisions in the national forest proclamation related to joint community-state ownership of forests. Project implementers must constantly work towards improving short term incentives from PFM, as these may be insufficient to garner support for PFM. Other necessary elements for PFM to succeed include: ensuring active participation of the communities in the process; and, clarifying and harmonizing the rules and regulations at different levels. 相似文献
13.
A tsunami, triggered by a massive undersea earthquake off Sumatra in Indonesia, greatly devastated the lives, property and infrastructure of coastal communities in the coastal states of India, Andaman and Nicobar Islands, Indonesia, Sri Lanka, Malaysia and Thailand. This event attracted the attention of environmental managers at all levels, local, national, regional and global. It also shifted the focus from the impact of human activities on the environment to the impacts of natural hazards. Recovery/reconstruction of these areas is highly challenging. A clear understanding of the complex dynamics of the coast and the types of challenges faced by the several stakeholders of the coast is required. Issues such as sustainability, equity and community participation assume importance. The concept of ICZM (integrated coastal zone management) has been effectively used in most parts of the world. This concept emphasizes the holistic assessment of the coast and a multidisciplinary analysis using participatory processes. It integrates anthropocentric and eco-centric approaches. This paper documents several issues involved in the recovery of tsunami-affected areas and recommends the application of the ICZM concept to the reconstruction efforts. 相似文献
14.
Daniela A. Guitart Catherine M. Pickering 《Journal of Environmental Planning and Management》2015,58(2):189-212
While claims about the environmental benefits of community gardens abound, few researchers have systematically assessed the ecological integrity of gardening practices. This study investigated gardening practices in 50 community gardens in Brisbane and Gold Coast cities, Australia. The study aimed to better understand how gardening practices might affect the ecological viability of community gardens. Factors investigated included: garden bio-physical characteristics, operators’ motivations, gardeners’ socio-demographic backgrounds, garden facilities and types of plants grown. Two broad types of gardens were identified: permaculture (21 gardens) and non-permaculture (29 gardens). Permaculture gardens used lower-impact gardening practices. Findings have policy implications for environmental planning and management. 相似文献
15.
The Western Forest Complex (WEFCOM) of Thailand is comprised of many protected areas and has one of the highest wildlife populations in the country. Populations of wildlife in the WEFCOM have decreased dramatically over recent years. Rapid economic development has resulted in the conversion of forest into agricultural and pastoral land, which has directly and indirectly impacted the wildlife community. This research aimed to evaluate populations of domesticated cattle (Bos indicus) and buffalo (Bubalus bubalis) in the WEFCOM and their possible impacts on the wildlife community. Domesticated cattle and buffalo keepers from 1561 (or 3.3%) of houses in and near WEFCOM were interviewed. The average number of animals per household was 15.6 cattle and 8.5 buffalo. Most villagers released domesticated cattle and buffalo to forage in the protected areas. This tended to have a high impact on the wildlife community in Huai Kha Khaeng Wildlife Sanctuary and Tungyai Naresuan Wildlife Sanctuary. The least impacted areas were Luam Khlong Ngu National Park, Thong Pha Phum National Park and Chaleam Ratanakosin National Park. With a high risk to the wildlife community, law enforcement should be used in combination with a certain level of co-management with local communities. 相似文献
16.
Sustainability of farmers' soil fertility management practices: a case study in the North China Plain 总被引:8,自引:0,他引:8
To ensure regional self-sufficiency and adequate rural livelihoods in the North China Plain (NCP), tremendous efforts were made over the last two decades by the Chinese government to raise the productivity of crops, despite increasing pressure on the land caused by a growing population. Emphasis was placed on high external input use, especially for wheat, maize and cotton, ignoring the particularities and limitations of the natural resource base. This study assesses the sustainability of current soil fertility management practices on the basis of selected location-specific indicators, such as fertilizer use, soil pH, soil organic matter content, levels of nitrogen (N), phosphorus (P) and potassium (K) in the soil, and identifies determining factors of the yield and environmental impacts of inputs use. Data used for the analysis were gathered from soil tests, groundwater and chive plant tests, household surveys, and statistical yearbooks. Stepwise multiple regression analysis is applied to determine factors affecting the yields. The study revealed unbalanced use of nutrients. Organic fertilizers (manure, crop residues) and K are insufficiently applied, whereas N and P are considerably overused in comparison with recommended doses. The intensive cropping in the area using high-input technologies -particularly fertilizer- has resulted in a remarkable general enhancement of crop productivity and improvement of soil fertility over the years. The yield of wheat and maize has increased 173 and 180 kg ha(-1) annually from 1982 to 2000, respectively and soil fertility status also improved over the years and the values of the selected indicators are within the borderline for sustainability. Irrigation water, FYM application, and total labor used during the cultivation season (with the exception of cotton and chive) for production are the main factors determining the yields of four major crops under study, while popularly and overly used N did not appear to be a significant factor affecting the yield. Its overuse, however, leads to leaching of nitrate into groundwater and nitrate enrichment of vegetables. Of 20 groundwater samples, 16 showed nitrate levels between 55 and 180 mg l(-1), which exceeds recommendations for drinking water (相似文献
17.
The integration of local harvesters' knowledge of attitudes and practices toward the resources they harvest with scientific information is essential to natural resources management. However, the development and implementation of management policies have, in most cases, not been effective because of a failure to use all available sources of information and knowledge. In fisheries management, local knowledge is usually not collected in a systematic format and little published literature has discussed the use of local knowledge data collection and analysis methods. This paper describes the implementation of geographic information systems to systematize, analyze, and display traditional and scientific information to support fisheries management in the Patos Lagoon Estuary, southern Brazil. Artisanal fishing data were documented through a series of interviews conducted during and after fishing trips at harvest spots, and scientific data on environmental variables were obtained from different research institutions. A multi-layer GIS database integrating local fishers' and scientific knowledge information was developed with ArcGIS 8.3 ArcView tools to integrate and translate information into an accessible and interpretable format. The geo-spatial database interface allowed the selection of specific data characteristics by target species, harvest areas, fishers' communities, fishing gear, catch-per-unit of effort (CPUE), and monthly landings. The observed fishing spatial dynamics presented among the fishers' communities shows that, in most cases, artisanal fishermen tend to concentrate in shallow estuarine waters surrounding their villages. 相似文献
18.
Li S Elliott JA Tiessen KH Yarotski J Lobb DA Flaten DN 《Journal of environmental quality》2011,40(5):1627-1642
Most beneficial management practices (BMPs) recommended for reducing nutrient losses from agricultural land have been established and tested in temperate and humid regions. Previous studies on the effects of these BMPs in cold-climate regions, especially at the small watershed scale, are rare. In this study, runoff and water quality were monitored from 1999 to 2008 at the outlets of two subwatersheds in the South Tobacco Creek watershed in Manitoba, Canada. Five BMPs-a holding pond below a beef cattle overwintering feedlot, riparian zone and grassed waterway management, grazing restriction, perennial forage conversion, and nutrient management-were implemented in one of these two subwatersheds beginning in 2005. We determined that >80% of the N and P in runoff at the outlets of the two subwatersheds were lost in dissolved forms, ≈ 50% during snowmelt events and ≈ 33% during rainfall events. When all snowmelt- and rainfall-induced runoff events were considered, the five BMPs collectively decreased total N (TN) and total P (TP) exports in runoff at the treatment subwatershed outlet by 41 and 38%, respectively. The corresponding reductions in flow-weighted mean concentrations (FWMCs) were 43% for TN and 32% for TP. In most cases, similar reductions in exports and FWMCs were measured for both dissolved and particulate forms of N and P, and during both rainfall and snowmelt-induced runoff events. Indirect assessment suggests that retention of nutrients in the holding pond could account for as much as 63 and 57%, respectively, of the BMP-induced reductions in TN and TP exports at the treatment subwatershed outlet. The nutrient management BMP was estimated to have reduced N and P inputs on land by 36 and 59%, respectively, in part due to the lower rates of nutrient application to fields converted from annual crop to perennial forage. Overall, even though the proportional contributions of individual BMPs were not directly measured in this study, the collective reduction of nutrient losses from the five BMPs was substantial. 相似文献
19.
河南省畜禽粪便污染及耕地负荷时空变化特征分析 总被引:2,自引:0,他引:2
为了解河南省畜禽养殖废弃物对环境污染的影响,根据河南省2006年~ 2012年统计数据,以各地级市为单位,分析了2006年~ 2012年河南省主要畜禽粪便产生总量及养分总量、单位耕地面积粪便负荷量及其污染风险预警.结果表明:河南省畜禽粪便产生总量约为28627万吨,猪粪和牛粪占粪便总量的84.5%以上,畜禽粪便还田后,粪便中的养分含量将对该省的水环境造成污染;河南省耕地畜禽粪便负荷预警级别在I级与Ⅳ级之间,风险较高的地市主要集中在漯河、鹤壁等市,尤其是鹤壁市,负荷量最高达59t/hm2.因此,这些地级市应该加强畜禽粪便的风险管理和综合治理工作. 相似文献
20.
《Journal of Environmental Policy & Planning》2012,14(2):163-175
In this paper, we explore the dissemination potential of organic farming in Andalucía, using the case of Olivarera de los Pedroches, a small farmer cooperative. This will be done in the search for an agroecological strategy in the olive tree organic agricultural sector. A comparative analysis of organic and conventional olive oil production is made: both in economic terms, and regarding employment creation, taking into account its environmental benefits. This will permit us to shed light on certain elements necessary in the design of rural policies linked to this economic sector, and in the family farming social stratum. After a brief analysis of the Andalucían inequality structure in rural areas—both historically and at present times—this work presents the following issues: (i) a systematic characterization of European olive cultivation, with special reference to the Spanish and Andalucían situations; (ii) an exploration of the socio-economic impact of the case study within the context of the major actors involved, and their relations in terms of its reproducibility, taking into account their relationships with institutional and policy arrangements. Organic agriculture in Spain has developed slowly since 1995—the year in which aid towards this type of production began to be established—and, at present, begins to show an exponential increase. Many farmers began the transition to ecological handling of olive groves. Consequently, the organic management of the olive groves and the sale of organic olive oil can be a stimulus to farmers to increase their profits. Hence, it can be a fundamental pillar on which to establish rural development in areas with a high level of importance concerning this crop. In this work, data clearly show that, in spite of high costs, organic olive farming has advantages over conventional agriculture in terms of incomes and employment. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献