857 resultados para Restoration and conservation


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拉萨河流域的亚高山落叶阔叶灌丛,以前尚无专门报导。本文对该类灌丛下的土壤、植物区系成份、生活型作了分析、统计,并应用TWINSPAN和DCA方法把野外调查的样地划分为七个群落类型,分别描述它们的群落特征:在将亚高山落叶阔叶灌丛与同其在垂直带中上下相接的其它灌丛分别对比后,对其植被地理学问题作了探讨,并进一步确定了这类灌丛的性质。研究表明.亚高山落叶阔叶灌丛因处于向森林区的过渡地带上,而与之具有一定的联系;在植被分布上表现为拉萨地区的相对偏湿气候与垂直带的产物,因而不能认为是本地区的“高原地带性”植被。关于该类灌丛的来源方面,初步认为包含有原生以及次生类型,还有待于进一步研究。最后,探讨了该类灌丛及群落中经济植物的利用与保护问题:其中着重于充分利用当地的自然条件,增加植被覆盖,进行植被改造。

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从生态地理背景论草地畜牧业产业在黄土高原农业可持续发展中的战略地位 黄土高原要实现生态与生产双赢的目标,契机是退耕还林还草,突破口是建立能兼顾生态生产协调发展的主导产业。从地形地貌、水热分布及自然植被特征的角度分析,黄土高原实施以农为主或农林牧综合发展的方略,均有悖于黄土高原生态地理背景。而草地畜牧业产业的生产要素及其过程在较大程度上吻合了黄土高原的生态地理背景,具有生态的适应性和生产的有效性,应作为黄土高原优化的生态生产范式建制中的主导产业。未来黄土高原产业的发展格局应该是以草地畜牧业为主导,农业和林业作为补充和完善的产业发展体系。此外,未来黄土高原草地畜牧业家畜养殖应以舍饲为主。 黄土高原自然植被演替过程中的物种特征与土壤养分动态研究 在3—149年的时间尺度上,对黄土高原自然植被次生演替过程中物种特征和土壤养分动态进行了研究。结果表明:1)随着演替时间尺度的延伸,土壤全C、全N含量呈增加趋势,而土壤全K、全Na和土壤pH值呈下降趋势,土壤全P变化趋势不明显;此外,表层( 0~10 cm)土壤Ca0含量呈下降趋势,深层( 20-30 cm,40-50 cm)则呈增加趋势。演替过程对土壤养分动态影响的程度随着取样深度的增加而减弱;2)植物群落物种丰富度在演替的中间阶段最高,后者对应于中等土壤养分水平;3)在演替的早期阶段,植物群落优势种往往具有稳定的土壤种子库,CR-生活史对策和S.繁殖对策,在贫瘠的土壤上具有较强的竞争能力;而具有较强的水平扩展能力和克隆繁殖能力,C-生活史对策、对土壤C,N具有较强竞争能力的多年生植物在演替中后期占据群落的优势地位。此外,在所涉及的物种生物学特征中,多年生生活史,C-、CR-、SC-、SR-、S.对策,以及R-、W-、Bs-、VBs-和V-繁殖对策等在非优势物种中有较高的出现频率。4)C-、 SC-对策,克隆能力,多年生生活史,水平扩展能力,种子的动物传播方式,秋季开花,荚果、坚果等特征的比例在一定程度上与土壤全C,全N和全K含量正相关; 而S一、SR-、R-、CR-对策,一、二年生生活史,种子繁殖,S.繁殖对策,以及胞果、蒴果等特征的比例与土壤全Na,Ca0含量和土壤pH正相关。在演替过程中出现的物种均属草本植物生活型,因此,草原可能是黄土高原上受制于大尺度环境条件(显域生境)下的优势植被类型(特别是降雨量不超过550 mm的地区)。 黄土高原植被恢复过程中几种优势植物叶片碳稳定性同位素和氮含量的动态特征 探讨了黄土高原植被恢复过程中六种优势植物叶片碳稳定性同位素(6 13C)和氮含量的季节动态、种间差异及其与植被恢复过程的关系。六种优势植物分别是猪毛蒿( Artemisia scoparia),出现在演替的先锋阶段:达乌里胡枝子( Lespedeza davurica),出现在演替的第二阶段;长芒草(Stipabungeana)、万年蒿(Artemisia gmelinii)和茭蒿(Artemisia giraldii),出现在演替的第三阶段; 白羊草( Bothriochloa ischaemun)出现在演替的顶级阶段。六种优势植物叶片碳稳定性同位素比率分别是-26.89±0.66‰,-26.24±0.48‰, -26.21±0.49‰, -26.86±1.09‰, -27.61±0.39‰和-15 .81±1. 79‰;氮含量分别是2.36±0.63%,2.38±0.29%,2.0±0.29%,2.0±0.25%,1.50±0.37% 和1.24±0.19%。白羊草、长芒草、茭蒿和达乌里胡枝子叶片氮含量季节变化与土壤水分呈正相关.猪毛蒿和铁杆蒿叶片氮含量季节变化与土壤水分呈负相关。白羊草叶片δ 13C与土壤水分呈正相关,而其他5个优势种叶片δ 13C与土壤水分呈负相关。不同演替阶段优势种的δ 13C值和氮含量特征表明:处于演替顶级阶段的优势种具有最高的水分利用效率,净光合产量较低,但光合作用动态对土壤水分的季节波动表现出较强的可塑性;相反,处于先锋阶段的优势种水分利用效率较低,叶片净光合产量较高,光合作用对土壤水分波动的可塑性较低。本文的主要结论是:黄土高原植被恢复过程中处于不同演替阶段的优势种无论是在叶片δ 13C,氮含量均存在差异。优势种叶片δ 13C和氮含量季节动态反映了不同物种在环境(主要指土壤水分)波动条件下的生理生态对策。具有最高的水分利用效率(而非最高光和能力)和最高光合可塑性的物种将成为黄土高原自然植被顶级植物群落中的最终统治者。 黄土高原草地畜牧业产业形成与发展的牧草生产力基础 遵循生产-生态兼顾的原则,在黄土高原197个区县土地利用方式重新规划的基础上,对支撑黄土高原畜牧业产业形成与发展的牧草生产潜力进行了分析预测。结果表明:规划的牧、林、农、果用地占生产用地的比例分别是草地44%、林地22%、基本农田20%、果园14%; 197个县区预测的总牧草生产潜力达1,0488,1028t.y-l,可载畜1,0488,1028个羊单位.y-1。按1999年不变价格计算,黄土高原预测的畜牧业总产值将达到524,4051万元.y-1,是1999年畜牧业总产值的5.3倍,超过1999年黄土高原农业总产值14 %。农业人口人均预测畜牧业产值大于1000元的区县占59%;小于1000元的区县占41%。此外,黄土高原预测的农业总产值将达到1147.2234亿元RMB.yr-1。畜牧业、果业、林业和基本农田产值占农业总产值的比例分别是46%、27%、14%和13%。随着畜牧业产业链的逐步建立与完善,产业发展布局的日趋合理,黄土高原畜牧业生产总值将有较大幅度的提高。黄土高原草地畜牧业蕴藏着巨大的发展潜力,有望成为黄土高原优化的生产.生态范式建制中的主导产业。

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城市化是引起生物多样性降低的主要原因之一,因此,应特别注意城市区域和城市化过程中的生物多样性保护。北京近三十年来经历了最为持久的城市化过程,城市的迅速扩张,人口的快速增加和经济的蓬勃发展给北京的生态环境带了巨大的压力,也给生物多样性工作带来了巨大的挑战。为有效开展生物多样性保护工作,迫切需要开展北京生物多样性现状及保护对策的研究。北京市以前在生物多样性方面作过大量工作,但缺乏系统的整理。本文通过深入的现场调查和对已有文献资料的整理,对当前北京市维管植物多样性现状及问题作了分析,并提出相应对策,以期为北京生物多样性保护工作提供参考。主要内容如下: 1.北京市自然生态系统主要有森林生态系统、灌丛生态系统、草甸生态系统和湿地生态系统4种类型。在人类长期干扰下,各生态系统多为次生。目前森林生态系统面积逐步扩大,而草甸生态系统和湿地生态系统受人为活动破坏严重,呈现严重退化趋势。 2.整理关于北京物种新纪录的各种文献,结合野外调查,构建了北京维管植物多样性数据库。北京维管植物多样性比较丰富,已知维管植物有2276种,然而特有性不强,严格属于北京特有维管束植物仅有5种。境内共分布有25种国家重点保护植物,包括野大豆、紫椴、河北梨以及22种野生兰科植物。根据调查资料初步评估,确定40种植物在北京处于受威胁状态。 3.根据北京人口密度、城市人口比例以及建设土地比例,将北京市按城市化程度的高低划分为城区,近郊区、远郊区三个区域。物种丰富度以远郊区最高,城区次之,近郊区最低,而外来物种比例则以城区最高,远郊区最低。城区分布有北京市93%以上的外来种,是其物种丰富度较近郊区为高的原因之一。对北京市特有植物、受危植物、国家保护植物和北京市保护植物的分布的分析表明,远郊区分布有93%以上的上述植物,是北京市生物多样性的重点保护区域,而城区和近郊区也分别分布有近1/4和1/3,说明保护稀有濒危物种方面,城区和近郊区也不容忽视。 4.对北京市外来植物作了分析,认为北京有126种归化植物,其中47种为入侵植物。菊科、禾本科、大戟科和苋科在入侵植物中占优势,美洲为最大起源地,其次为欧洲。园艺苗木引种是入侵物种的主要侵入途径,导致海淀、丰台、西城、朝阳等城区分布有较多的入侵种。 5.对外来物种火炬树的地理分布格局和入侵潜力作了研究。火炬树在人为大力推广下已遍布各风景区,在公路两侧也常见分布并侵入农田,甚至出现在某些自然保护区。火炬树在贫瘠和肥沃生境下均具有较高的繁殖速度,在3年内靠克隆繁殖扩散距离已超过6米,并能行成郁闭度很高的单优群落,其物种丰富度、个体密度以及物种多样性指数均显著低于本地荆条灌丛群落。由于其强阳性生长特性,使其不能侵入森林,然而却能对灌丛生态系统构成危害,其克隆繁殖的特点也使其难以根除,在北京地区具有潜在的入侵能力,不适合继续作为绿化北京的主要树种。 6.北京市生物多样性面临的主要问题包括城区本土生物多样性低、生态系统退化、湿地萎缩、污染严重、强度的旅游开发和外来物种入侵等。本文对这些问题作了分析,提出在城区大力应用本地种构建自然群落,对退化生态系统因势利导结合人工和自然力进行恢复,规范旅游活动向生态旅游方向发展,加强公众教育,促进全社会参与生物多样性保护工作。

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钾是作物生长发育的必需矿质元素,缺钾对大豆产量和营养品质影响显著。硅是植物的有益元素,在低钾胁迫条件下,硅对大豆生长是否有改善作用还未见相关报道,本研究以对低钾敏感的不同基因型大豆品种(铁丰35和铁丰31)为试验材料,在低钾条件下(1 mmol L-1),施加Na2SiO3,通过大豆生物量、根系形态学、生理学和抗氧化物酶活性等参数的变化,研究硅在大豆缺钾胁迫生长中的作用。主要研究结果如下: 1低钾胁迫对大豆生长发育和生理指标形状的影响 与正常钾生长条件(5 mmol L-1)相比,对低钾敏感的基因型大豆品种铁丰35,低钾胁迫使铁丰35品种主根、侧根,过氧化氢 (H2O2)和丙二醛含量(MDA),根系和叶片的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性和光合特性指标等发生显著变化,同样地,铁丰31品种根系的SOD、CAT、POD活性和MDA含量也发生显著变化。相反,铁丰31品种的其它形态学和生理学指标参数受低钾胁迫影响差异不显著。 2 Si和Na+对大豆生长发育和生理过程中低钾胁迫的减缓作用 为探明Si对大豆生长发育和生理过程中低钾胁迫的减缓作用,我们将Na2SiO3分别设立3个浓度处理水平(0.1, 2.0, 5.0 mmol L-1),对照CK0:5.0 mmol/L KNO3+0.0 mmol/L Na2SiO3,副对照CK1:1.0 mmol/L KNO3+4.0mmol/L NaCl,其中以Si2处理是2个品种减缓低钾胁迫效应最好的,对大豆生长发育和促进大豆根、茎和叶内钾浓度含量,低钾胁迫使SOD、POD、CAT活性,H2O2和MDA含量,以及光合特性(Pn, WUE)等指标参数得以显著地改善,但Na2SiO3对低钾敏感品种铁丰35的减缓作用远大于对低钾不敏感的品种铁丰31。为排除Na2SiO3中Na+对低钾大豆的生长作用,用等浓度NaCl进行检验,结果表明,Na+可以部分地减缓低钾胁迫,并且这减缓作用远小于等浓度的Si。本试验结果说明Si通过改变几个关键的生理过程,进而提高低钾胁迫条件下,大豆生长发育的表达活力,以有效地改善低钾对大豆生长的胁迫。 3 Si通过提高抗氧化胁迫进而减缓大豆生长发育中低钾胁迫 低钾胁迫使大豆地上和地下生物产量与对照CK0相比显著减少,增施Na2SiO3前后大豆其根冠比、过氧化氢积累、钾含量、膜质过氧化产物和抗氧化物酶活性变化显著。另外,Na2SiO3显著减缓了低钾胁迫使大豆根冠比、提高了低钾大豆根、茎、叶内钾浓度,Si还减缓了过氧化氢 (H2O2)和丙二醛含量(MDA),这说明Si抑制了低钾的过氧化胁迫,显著地抑制了因低钾胁迫而使超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)等活性的升高,这些酶活性提高效应被施加的Na2SiO3消除,这些结果表明,Si通过提高抗氧化胁迫能力,进而减缓大豆生长发育的低钾胁迫,对低钾胁迫有非常重要的减缓调控作用。

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During the reporting period, NaFIRRI realigned its projects under ARTP II extension to focus on: 1. Determination of appropriate technologies and methods for harvesting and conservation of fish species in the Albert and Kyoga Systems 2. Impact of policies and technologies on livelihoods 3. Generation of knowledge for the management of aquatic invasive weeds and their hot spots in Lakes Albert and Kyoga 5. Determination of environmental factors influencing productivity for fisheries in Lakes Albert and Kyoga Systems 6. MSI - Nile perch project 7. Adaptation and Facilitating Dissemination of Appropriate technologies for harvesting Commercial Species 8. Identification of fish species suitable for culture and marketing, and promotion of their commercial culture in the Eastern AEZ.

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The annual report presents present activities and achievements for the reporting year 2011/2012. The Objectives of NaFIRRI are highlighted below: a) Generation of knowledge and technologies of strategic importance for the management, development and conservation of fisheries resources and water quality. b) Establishment and management of the human, physical and financial resources of the National Fisheries Resources Research Institute. c) Provision of technical backstopping and capacity building to the Ministry of Agriculture, Animal Industry and Fisheries (MAAIF), Zonal Agricultural Research and Development Institutes (ZARDIs) and other agencies dealing in fisheries research and water quality. d) Development and management of fisheries research information and ensuring collaboration with stakeholders. e) Planning, monitoring and evaluation of all fisheries research programmes undertaken by the institute to ensure conformity with national research strategy. f) Ensuring the quality of knowledge and technologies developed, multiplied and disseminated through uptake pathways. g) Generation of periodic reports on fisheries and water quality research programmes to National Agricultural Research Council (NARC) and other stakeholders. h) Establishment of sustainable linkages and partnerships with local, regional and international research bodies.

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The demand for brooders of Penaeus monodon by the hatcheries, which are solely dependant on wild brooders for their seed production, has resulted in a vigorous fishery and trade for this species, especially along the Visakhapatnam coast. More than three hundred brooders are brought in per day for trading during the peak landing season from December to March every year. The price of gravid brooders has been declining over the years but on an average is about Rs. 30,000 per brooder. The total length of male brooders ranged from 190 to 246 mm during the three years under study and for females it varied between 210 and 330 mm. A specialized methodology for transportation, storage and trade of P. monodon brooders has been evolved over the years at Visakhapatnam Fishing Harbour. Concentrated exploitation of brooders from the wild and presence of pathogens in them makes a strong case for development of specific pathogen free brooders and conservation of wild stock.

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The diversity indices can be used as a good measure for studying the effect of industrial pollution because industrial wastes and sewage almost always reduce the diversity of natural systems into which they are discharged. A measurement of diversity often provides a better index of pollution than a direct measurement of pollutants. The assessment of macrobenthos diversity with respect to diversity indices reflects the marine population and habitat disturbance, and also serves as an important indicator of environmental conditions. The present study was designed to investigate the diversity indices of selected macrobenthos at two ecologically distinct locations on the Karanja creek (District - Raigad), Maharashtra, west coast of India. Results on various diversity indices like Index of Frequency (F) or Importance Probability (Pi), Index of Dominance (c), Rarity Index (R), Shannon's Index of General Diversity (H¹) Margaf’s Richness Index (R sub(1)) and Evenness Index (e) did not vary significantly. This demonstrates that at present, Karanja creek harbours varied forms of macrobenthic community showing no effect of human disturbance, but in future, measures must be taken for the protection and conservation of macrobenthic community of the creek.

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The inadequate planning and inefficient management of coastal aquaculture has resulted into serious socioeconomic consequences. These are the displacement of rural communities which traditionally depended on mangroves due to large-scale mangrove conversion for shrimp and fish farming, land subsidence caused by excessive pumping of groundwater for use in aquaculture, financial losses due to disease outbreaks, and public health consequences due to red tide. In order to maximize the socioeconomic benefits of coastal aquaculture the adoption of the principles of sustainable development is recommended. Sustainable development is the management and conservation of natural resource base and the orientation of technological and institutional change in such a manner to ensure the attainment and continued satisfaction of human needs for present and future generations.

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The article discusses some strategies in the establishment of a mangrove genetic garden where species could be maintained. The genetic garden is a sustainable way to prevent further damage of the remaining mangroves. Its prime function is the protection and conservation of mangroves for sustainable use.

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黑长臂猿(H y lobates concolor) 是现生11 种长臂猿中其系统地位最低的灵长类。历史时期 长臂猿曾广泛分布在我国南部的大部省区。自公元4 世纪以来, 它们的分布发生了很大变化。分 布区从北到南, 从东到西急剧缩小, 现黑长臂猿缩小到只在海南岛、云南南部和越南北部, 已 分化为6 个亚种。分布于我国的5 亚种中, 海南亚种(H. c. hainanus) 现今仅20 余只, 是最 濒危的一个亚种; . 北部湾亚种(H. c. nasu tus) 50 年代曾在广西西南部发现, 60- 70 年代已绝 迹; 指名亚种(H. c. concolor) 主要分布于越南北部、滇南和滇中哀牢山。滇南约有100 余只, 滇中哀牢山可能有40- 60 群, 180- 240 只; 景东亚种(H. c. j ing d ong ensis) 为滇中无量山的 特有亚种, 现有100- 116 群, 430- 500 只; 滇西亚种(H. c. f u rvog aster) , 只分布在滇西南的 沧源、镇康、云县和耿马等地, 约有26- 42 群, 100- 150 只。现今, 黑长臂猿的分布区已不足 1 000Km 2, 总数量约1 000 只, 为高度濒危的灵长类动物。造成黑长臂猿濒危的主要原因是: 热 带和南亚热带原始森林的被破坏和缩小、人类活动的干扰使生境破碎和恶化、过度猎捕和长臂 猿自身的生物学弱点。目前, 中国的黑长臂猿已在9 个自然保护区中得到保护。

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Crocodiles have a long breeding life, which ranges from 25-30 years. There are 27 species and subspecies of crocodiles throughout the world, 18 of which are in danger of extinction, the rest being threatened with declining population due to overhunting and habitat destruction. Two known crocodile species exist in the Philippines: Crocodylus mindorensis (freshwater crocodile) and C. porosus (saltwater crocodile). Killing adult crocodiles, as is being done now, drastically reduces the potential population. Moreover, toxic wastes from mines, destruction of marshes and riverine habitats, and the conversion of their natural habitats for fishponds additionally threaten their populations. Estimates indicate that there are only about 100 Philippine crocodiles in the wild now. The Crocodile Farming Institute (CFI) was established in Palawan, in 1987, in order to save the crocodiles from extinction in the Philippines. It is now one of the components of the Palawan Wildlife and Conservation Center, and aims to conserve the 2 endangered species in the Philippines and also to develop and introduce a suitable crocodile farming technology that will help uplift the socio-economic well-being of the Filipino people. CFI believes in the potential of commercial utilization of crocodiles as a dollar-generating industry for the Philippines. It is a very profitable business and could be a multi-million dollar industry. A brief outline is given of the economic and marketing potentials of farming crocodiles in the Philippines.

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Kisinja (Barbus altianalis)is an indigenous omnivorous fish, of high economic value in Uganda. It was widely distributed in most lakes and rivers in the country but its stocks were depleted due to overfishing and degradation of its natural habitat. 1t can grow up to a maximum length of 120m and a weight of 15kg in the wild and grows faster, attains larger size than commonly farmed fishes in Uganda, including the Nile tilapia, the African catfish, and mirror carp. Kisinja is a highly valuable table fish with good taste and aroma especially when smoked. Increased production of Kisinja is therefore necessary to meet economic and nutritional benefits of the communities and conservation of the spedes.

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The Annual report presents activities carried out by the Organization during the period 1973. It presents scientific work of the Organization which include: Tissue specificity of malate dehydrogenase in Astatoreochromis and two species of haplochromis, report on LaKe Babati Fishery, Observations on Engraulicypris orgenteus (PELLEGRIN) 1904 from Lake Victoria, Commercial trawl fishing on Lake Victoria: Fisheries development and conservation, Lunar periodicity and the breeding of Tilapia nilotica in the Northern part of Lake Victoria.