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1.
西藏是我国天然草原面积最大的地区,公路为区域最主要的交通运输方式。在公路建设过程中,临时工程的设置将不可避免占用草原,使原地貌和地表植被遭到破坏。当草原生态环境遭受损害后,公路建设单位理应对损害的草原承担一定的赔偿费,以用于被损害草原的修复。以西藏某公路项目为研究对象,提出了基于ENVI和ARCGIS技术的公路占用草原类型和面积识别方法;在对草原价值构成分析的基础上,探讨适于公路建设草原生态赔偿费核算的理论框架与方法,并通过对普兰县、札达县调查发现,部分受偿牧民因两地赔偿标准差异较大而认为赔偿工作有失公平。据此,文章提出草原生态赔偿费核算所采用的标准应在当地草地补偿标准的基础上,同时考虑赔偿主体和受偿客体双方的支付和受偿意愿,增加调整系数,以提高赔偿费的合理性和赔偿工作的可行性。  相似文献   

2.
内蒙古自治区较为完整地传承和保留了草原文化和草原文化遗存,作为草原文化遗产的代表地,通过搜集元上都遗址地的游客游记,采用内容分析法、ROST CM6高频词频分析法和NET DRAW共现关系网络分析法,对草原文化遗产管理与遗产旅游地形象塑造进行了分析,并分析了草原遗产旅游地加强文化遗产管理的意义。结果表明:采用虚拟现实技术,以实现遗产地旅游形象重塑,只有做好文化遗产管理,才能实现遗产旅游地的形象重塑。在研究结论的基础上,主要从三个方面提出建议:提出了自然环境保护是重塑旅游地形象的重要部分,遗址旅游地管理弱化将影响到旅游者对认知形象的识别;遗产旅游地外部需优化交通线路,内部需进行主题整合,提升旅游地形象;遗产地管理者必须以保护和传承草原文化遗产来促进遗产地旅游业发展。  相似文献   

3.
新疆草原面积广阔、类型多样,旅游资源丰富,具有很大的发展潜力,但目前很少对新疆的草原旅游资源进行研究.分析了新疆草原旅游资源规模大、分布广、类型多样、民俗文化多元但自然生态和人文生态都极为脆弱等特征,对目前新疆草原旅游资源开发现状和存在的问题进行了全面和深入的探讨,提出了新疆草原旅游资源可持续开发的思路,以促进新疆草原地区旅游业发展.  相似文献   

4.
以库鲁斯台草原作为研究区,利用80年代到2014年草原范围内生物量、牲畜量、耕地数量及其用水量等数据,对库鲁斯台草原退化现状及原因进行了分析,结果如下:(1)目前库鲁斯台草原退化严重。草原范围内湿地面积从80年代至2014年减少了85.0%、草地可利用面积减少了36.5%、退化草地面积增加了225%、盐碱化面积增加了233%、草地沙漠化面积增加了2350%。(2)库鲁斯台草原退化主要原因,一是农业用水大幅增加。草原范围内总灌溉面积从80年代至2014年增加了186%、草原内机电井数增加了292%;从80年代到90年代到2000年,额敏河流域总用水量呈先增后减的趋势,从2000年又呈大幅增加的趋势,总用水量从80年代至目前增加了36.11%。二是草地牲畜数量大幅增加,引起草地生物量减少,草原范围内牧业户数从80年代至2014年增加了24%,草原内过冬牲畜量增加了45.6%,草地总产量减少了64.43%。  相似文献   

5.
<正>胜境河北,草原资源丰富,全省草原面积达4 266万亩,其中张家口、承德地区就有3 358.4万亩,占全省草原面积的78.7%。坝上草原的清凉无夏,草原天路的美不胜收,与内蒙的乌兰布统自然保护区交相呼应,早已成为河北的靓丽名片。张北草原天路,全长130多公里。秀美草原不仅可以观光游览,更是调节地域生态平衡的重要一环。草原具有保持水土、涵养水源、防风固沙的重要作用,对于维护生态平衡  相似文献   

6.
要闻     
《环境教育》2013,(11):5-5
农业部首发《中国草原发展报告》 农业部近日发布《中闫草原发展报告》,首次对我国草原法制建设、政策支持、执法监督等方面的工作和成效进行了系统全而梳理。报告显示,  相似文献   

7.
吉林省白城地区草原位于松嫩草原的中心,是著名的科尔沁大草原的东端部分。辽阔的草原不仅为发展经济提供了丰富的资源,而且对调解生态产生重大影响。六、七十年代,由于人们缺少环境意识,忽视草原生态保护,滥垦、滥收、滥樵、滥挖药材等掠夺式的利用草原资源,加剧了草场的恶化。形成了农田吃草原,风沙吃农田的恶性循环,农业生态系遭受严重破坏。致使水土流失、生态结构失调、草原功能减退,沙化、碱化、风化日趋严重。根据资料统计,1980年全区草原总面积比50年代减少了415万亩,可利用面积减少521万  相似文献   

8.
为了全面了解宁夏草原生态保护与管理政策对宁夏主要草原地区草原生态、草畜产业发展和农牧民生产生活的影响,运用灰色关联度分析农牧民对草原保护与管理政策认知,进行主要影响因素关联度排序。结果表明:农牧民对草原政策的认知,受农牧民文化程度、个人社会身份、家庭草原面积以及是否从事养殖业等多种因素的交互影响。由此提出通过加强草原地区农业技术推广、大力推进草原确权登记工作、加强乡村自治淳化质朴民风等措施进一步巩固生态保护与管理成果,实现草原生态保护、生产发展与农牧民增收相统一协调,提高宁夏草原可持续发展能力。  相似文献   

9.
大气氮沉降增加是全球变化的重要现象之一,草原生态系统对氮沉降增加的响应成为草地生态学的研究热点之一。凋落物分解是草原生态系统养分循环和能量流动的主要途径,氮沉降增加引起草原植物群落结构变化,导致凋落物质量、土壤肥力、土壤微生物和土壤动物的变化,最终影响凋落物的分解。本文综述了氮沉降对草原凋落物结构、化学组成和分解环境的影响等方面的国内外最新研究进展,讨论了需进一步加强研究的内容,以期为进一步拓展该领域研究的广度和深度、为全面分析和评估全球变化对草原生态系统的影响提供参考。  相似文献   

10.
2006年9月3日,天下溪教育咨询中心举行了“草原保护网络”的启动仪式,本次活动进行草原保护主题的参与式讨论和“草原的基本生态学”的专题讨论。活动中,通过团队游戏的方式,和同样关注草原的一群朋友相识,了解彼此。通过共同讨论,明确草原保护网络的定位、目标、产出以及每个机构与个人对于网络的需求与贡献,达成共识,建立协作关系。天下溪宋增明先生对“草原保护网络”的设想做了详细介绍。参与活动的专家、学以及媒体代表分别发表了对草原保护的构想。  相似文献   

11.
沙湾县三个泉子退耕还草项目区的建设,彻底改变了长期以来由于草地在陆地生态系统中的巨大作用和在国民经济发展中的重要地位未被充分认识,加之受传统的重农轻牧,重牧轻草,轻草贱草等社会思想的影响,彻底改变了草地建设等许多措施没有落到实处,尤其是草地生态建设的步伐远远不能适应生态环境发展要求的现状。  相似文献   

12.
Public rangelands in North America are typically managed under a multiple use policy that includes livestock grazing and wildlife management. In this article we report on the landscape level extent of grassland loss to shrub encroachment in a portion of the Rocky Mountain Forest Reserve in southwestern Alberta, Canada, and review the associated implications for simultaneously supporting livestock and wildlife populations while maintaining range health on this diminishing vegetation type. Digitized aerial photographs of 12 km of valley bottom from 1958 and 1974 were co-registered to ortho-rectified digital imagery taken in 1998, and an un-supervised classification used to determine areas associated with grassland and shrubland in each year. Field data from 2002 were over-layed using GPS coordinates to refine the classification using a calibration-validation procedure. Over the 40-year study period, open grasslands declined from 1,111 ha in 1958 to 465 ha in 1998, representing a 58% decrease. Using mean production data for grass and shrub dominated areas we then quantified aggregate changes in grazing capacity of both primary (grassland) and secondary (shrubland) habitats for livestock and wildlife. Total declines in grazing capacity from 1958 to 1998 totaled 2,744 Animal Unit Months (AUMs) of forage (−39%), including a 58% decrease in primary (i.e., open grassland) range, which was only partly offset by the availability of 1,357 AUMs within less productive and less accessible shrubland habitats. Our results indicate shrub encroachment has been extensive and significantly reduced forage availability to domestic livestock and wildlife, and will increase the difficulty of conserving remaining grasslands. Although current grazing capacities remain marginally above those specified by regulated grazing policies, it is clear that continued habitat change and decreases in forage availability are likely to threaten the condition of remaining grasslands. Unless shrub encroachment is arrested or grassland restoration initiated, reductions in aggregate ungulate numbers may be necessary.
Edward W. BorkEmail:
  相似文献   

13.
As woody plants encroach into grasslands, grass biomass, density and cover decline as wood plant biomass, density and cover increase. There is also a shift in location of the biomass from mostly belowground in the grasslands to aboveground in the woodlands. In addition, species richness and diversity change as herbaceous species are replaced by woody species. This is not a new phenomenon, but has been going on continually as the climate of the Planet has changed. However, in the past 160 years the changes have been unparalleled. The process is encroachment not invasion because woody species that have been increasing in density are native species and have been present in these communities for thousands of years. These indigenous or native woody species have increased in density, cover and biomass because of changes in one or more abiotic or biotic factors or conditions. Woody species that have increased in density and cover are not the cause of the encroachment, but the result of changes of other factors. Globally, the orbit of the Earth is becoming more circular and less elliptical, causing moderation of the climate. Additional global climate changing factors including elevated levels of CO2 and parallel increases in temperature are background factors and probably not the principal causes directing the current wave of encroachment. There is probably not a single reason for encroachment, but a combination of factors that are difficult to disentangle. The prime cause of the current and recent encroachment appears to be high and constant levels of grass herbivory by domestic animals. This herbivory reduces fine fuel with a concomitant reduction in fire frequency or in some cases a complete elimination of fire from these communities. Conditions would now favor the woody plants over the grasses. Reduced grass competition, woody plant seed dispersal and changes in animal populations seem to modify the rate of encroachment rather than being the cause. High concentrations of atmospheric CO2 are not required to explain current woody plant encroachment. Changes in these grassland communities will continue into the future but the specifics are difficult to predict. Density, cover and species composition will fluctuate and will probably continue to change. Increased levels of anthropogenic soil nitrogen suggest replacement of many legumes by other woody species. Modification and perhaps reversal of the changes in these former grassland communities will be an arduous, continuing and perhaps impossible management task.  相似文献   

14.
Phosphorus leaching from cow manure patches on soil columns   总被引:2,自引:0,他引:2  
The loss of P in overland flow or leachate from manure patches can impair surface water quality. We studied leaching of P from 10-cm-high lysimeters filled with intact grassland soil or with acid-washed sand. A manure patch was created on two grassland and two sand-filled lysimeters, and an additional two grass lysimeters served as blanks. Lysimeters were leached in the laboratory during 234 d with a diluted salt solution, and column effluent was passed through a 0.45-microm filter, analyzed for pH, dissolved reactive P (DRP), and total dissolved P (TDP). At the end of the experiment lysimeter soil was sampled and analyzed for pH, available P, and oxalate-extractable P, Fe, and Al. The concentration of TDP in the effluent from the sand column increased to 25 mg L-1 during the first weeks and remained above 10 mg L-1 during the rest of the percolation. In effluent from grass + patch lysimeters TDP gradually increased to 4 mg L-1. Both in the manure and in the effluent of the sand lysimeter P was found mainly in the form of DRP, but in the effluent from the grass lysimeters was found mainly as dissolved unreactive P (DUP=TDP-DRP). Earthworm activity was responsible for decomposition of the manure patch on the grass lysimeters. Manure patches and their remains were found to be a long-term source of high concentrations of P in leachates. Spreading of patches after a grazing period could reduce their possible negative impacts on the environment.  相似文献   

15.
塔里木河干流区退耕还林(草)改善生态措施探讨   总被引:11,自引:0,他引:11  
在国家实施西部大开发战略,提出退耕还林(草),再造山川秀美的历史机遇面前,针对塔里木河干流区尤其是下游绿色走廊生态环境恶化的现实问题,分析产生问题的具体原因,阐明在合理开发、利用和配置水资源的前提下,退耕还林(草)是改善生态环境的有力措施以及实施退耕还林(草)对改善该区域生态环境的作用和意义,论述退耕还林(草)应掌握和处理好改善生态与经济发展、改善生态与农业结构调整、现代技术应用与传统方式的关系,探讨退耕还林(草)中合理的林草比例及科学的林草结合方式。  相似文献   

16.
The semi-private property rights arrangement called the Household Production Responsibility System (HPRS) was started in the early 1980s in Xilingol pasture of Inner Mongolia (China), and stimulated the development of stockbreeding. The grassland has been degrading severely with increasing numbers of livestock. Based on a historical review of property rights regimes in Inner Mongolia and empirical surveys in Xilingol pasture during 2001-2003, this paper assesses the implementation of HPRS and its impacts on incomes of households as well as the environmental impact on the grassland. It was found that HPRS does not mitigate the "Tragedy of the Commons", instead it has exacerbated the situation. It was also found that co-management of grassland and livestock among a few households presents a sustainable use of grassland to develop livestock breeding. We conclude with the recommendation that small-scale collective property rights systems should be encouraged in Xilingol pasture of Inner Mongolia.  相似文献   

17.
Aeration has been promoted as improving infiltration of rainfall and extending grass or forage productivity, but research on the impact of this practice on P losses from grasslands has had mixed results. We designed a study to determine at the field scale, using a paired watershed approach, the impact of slit aeration on runoff volume and P losses in runoff from fescue (Festuca arundinacea Schreb.)/bermudagrass (Cynodon dactylon L.) hay fields fertilized with broiler litter. Three pairs of 0.8-ha fields, each with similar soils (Typic Kanhapludults, Aquic Hapludults, and Aquultic Hapludalfs), were fertilized with broiler litter and monitored under similar management from 1995 through 1998, then one field in each pair received aeration treatment from 2001 through 2003. In the field with mostly well-drained soils, grassland aeration reduced surface runoff volume and mass losses of dissolved reactive P (DRP) in runoff by approximately 35%. In contrast, when poorly drained soils dominated, grassland aeration increased runoff volume (4.8 mm/runoff event) and mass losses of DRP and total P (0.25 kg TP ha-1 per runoff event). This implies that aeration of well-drained soils in the top poultry-producing counties of Georgia (0.2 million ha) could decrease dissolved phosphorus losses by more than 500 Mg P each year. This is not the case if soils are poorly drained.  相似文献   

18.
The majority of research on organic farming has considered arable and grassland farming systems in Central and Northern Europe, whilst only a few studies have been carried out in Mediterranean agro-systems, such as vineyards, despite their economic importance. The main aim of the study was to test whether organic farming enhances local plant species richness in both crop and non-crop areas of vineyard farms located in intensive conventional landscapes. Nine conventional and nine organic farms were selected in an intensively cultivated region (i.e. no gradient in landscape composition) in northern Italy. In each farm, vascular plants were sampled in one vineyard and in two non-crop linear habitats, grass strips and hedgerows, adjacent to vineyards and therefore potentially influenced by farming. We used linear mixed models to test the effect of farming, and species longevity (annual vs. perennial) separately for the three habitat types. In our intensive agricultural landscapes organic farming promoted local plant species richness in vineyard fields, and grassland strips while we found no effect for linear hedgerows. Differences in species richness were not associated to differences in species composition, indicating that similar plant communities were hosted in vineyard farms independently of the management type. This negative effect of conventional farming was probably due to the use of herbicides, while mechanical operations and mowing regime did not differ between organic and conventional farms. In grassland strips, and only marginally in vineyards, we found that the positive effect of organic farming was more pronounced for perennial than annual species.  相似文献   

19.
/ Land condition trend analysis (LCTA) is a long-term monitoring program used on military training lands to identify ecological changes that result from training and management activities. We initiated LCTA at the Kansas Army National Guard Training Facility (KANGTF) in Saline County, Kansas, in March 1998. This paper evaluates the LCTA methodology for birds by comparing LCTA results with a modified methodology designed to place sampling transects in field-identified rather than satellite-identified land-cover types. In the satellite-identified land-cover types developed at the site, grassland habitats included a large component of woody vegetation, which resulted in poor resolution of bird assemblages associated with the different land-cover types. Using these cover classes, mixed grass prairie included five grass/forb (g/f) and 10 woody-dependent species; old-field included four g/f and four woody-dependent species; and riparian included one g/f and six woody-dependent species. LCTA sampling was too limited in the ecologically important riparian woodland habitat with the result that bird species were not adequately sampled there. In the alternate sampling strategy, we identified three land-cover classes (grassland, hedgerow, and riparian woodland) by field reconnaissance and increased sampling in the riparian woodland. Grassland included six g/f and three woody-dependent species; hedgerow included six g/f and 20 woody-dependent species, and riparian included two g/f and 19 woody-dependent species. The modifications greatly improved the resolution of bird assemblages associated with land-cover classes at the KANGTF. Use of the alternative sampling method should improve the ability to detect long-term trends in the bird communities.  相似文献   

20.
Grass vegetation has been recommended for use in the prevention and control of soil erosion because of its dense sward characteristics and stabilizing effect on the soil. A general assumption is that grassland environments suffer from minimal soil erosion and therefore present little threat to the water quality of surface waters in terms of sediment and sorbed contaminant pollution. Our data question this assumption, reporting results from one hydrological year of observations on a field-experiment monitoring overland flow, drain flow, fluxes of suspended solids, total phosphorus (TP), and molybdate-reactive phosphorus (<0.45 mum) in response to natural rainfall events. During individual rainfall events, 1-ha grassland lysimeters yield up to 15 kg of suspended solids, with concentrations in runoff waters of up to 400 mg L(-1). These concentrations exceed the water quality standards recommended by the European Freshwater Fisheries Directive (25 mg L(-1)) and the USEPA (80 mg L(-1)) and are beyond those reported to have caused chronic effects on freshwater aquatic organisms. Furthermore, TP concentrations in runoff waters from these field lysimeters exceeded 800 mug L(-1). These concentrations are in excess of those reported to cause eutrophication problems in rivers and lakes and contravene the ecoregional nutrient criteria in all of the USA ecoregions. This paper also examines how subsurface drainage, a common agricultural practice in intensively managed grasslands, influences the hydrology and export of sediment and nutrients from grasslands. This dataset suggests that we need to rethink the conceptual understanding of grasslands as non-erosive landscapes. Failure to acknowledge this will result in the noncompliance of surface waters to water quality standards.  相似文献   

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