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1.
大型野生动物种群数量估算的理想条件是使用数学模型以及严格的实验设计来选择样本。可是,野外条件状况往往违背数学模型假设前提,不可能随机地选择样本。于是,计算的结果不但不可靠,而且很可能没有意义。就野生动物管理来说,不需要获得一个准确的种群数量,只需一个长期的数量趋势,就足以指导相关管理工作。在中国大型哺乳动物长期监测还没有纳入常规。本文报道了位于青海省野牛沟和甘肃省阿克塞县两个野生有蹄类动物种群数量的长期趋势监测项目。我们这些年里一直用相同的方法持续监测,并明确了监测数值结果包含有不确定性。尽管存在不确定性,仍可以发现监测地点野生有蹄类动物种群变化趋势,这些结果可以帮助野生动物管理者据此变化及时作出相应管理计划。  相似文献   

2.
祁慧博  杜萌萌  龙飞  高晓玮 《生态学报》2023,43(9):3607-3624
在林业碳汇项目设计与作业标准基础上,将中国东北地区典型人工林生长与经营相关多源数据融合,运用系统动力学理论与方法,构建人工林生态经济系统模型,通过设计实施主伐/间伐、营造混交林、补植补造等不同生态调控情景,模拟并预测人工林可持续经营的生态—经济收益,以此掌握人工林生态调控机制,并为人工林可持续经营决策提供参考。模拟结果显示:(1)高初植密度能有效增汇,而低初植密度相比基准情景则减少了碳汇;(2)高主伐率使得木材收益大幅提升,而无主伐限制了木材收益,且从长期来看碳汇收益有限;(3)高密度-无主伐情景下的累计碳汇量最大,高密度-高主伐情景下的木材收益净现值和总收益净现值最大;若以可持续经营为目标,平衡生态收益和经济收益,则高密度-高主伐情景为理想选择,该情景的累计碳汇量相比高密度-无主伐情景损失有限,对应碳汇收益净现值为357.9万元,以5%贴现率计算的木材总收益和累计总收益的净现值分别为1219.35万元和1577.25万元。由此证实了以林业碳汇项目为依托,因地制宜地构建将造林、抚育、采伐、再造林更新于一体的人工林可持续经营项目,平衡发挥森林生态系统的综合功能,可纾解因无法采伐所带来的高...  相似文献   

3.
玛可河林区是青海玛可河林区省长江流域大渡河源头最集中的一片天然原始林区,是大渡河流域高山峡谷重点生态公益型林区,具有涵养水源、调节气候、保持水土等重要的生态功能。因此,玛可河林区森林资源的可持续经营成为当前主要任务。本文通过对玛可河林区的现状、可持续发展经营存在的问题以及对解决问题的对策进行了研究。  相似文献   

4.
第二届国际可持续农业会议于9月8—13日在北京蟹岛绿色生态度假村举行。此次会议经国家科技部批准,由中国科学院植物研究所主办,北京蟹岛绿色生态度假村、北京植物园和中国农业工程学会协办,并得到国家自然基金委、中国科学院南南合作基金、意大利环境部、德国信息技术研究所等单位的支持。 会议的主题为:发展可持续  相似文献   

5.
中国经过遗传改良的重要造林树种有100多种,全国年均提供各类林木种子2300万kg,年均生产各类良种壮苗约130亿株。林木良种在生产上的应用产生了明显的综合增益,其中用材林平均生长增益达10%~30%,经济林平均产量增益达15%~68%。中国每年进口林木种子15万kg以上,涉及50多个树种;每年出口林木种子30万kg和苗木400多种。近10年来,中国林木遗传资源的可持续经营和利用已取得了明显的进步,但与一些发达国家相比还存在一定差距。今后,应优先考虑对已保存的林木遗传资源的维护和资金补贴,加强种苗市场监管和信息服务,进一步提高林木良种的基地供种率和良种使用率。  相似文献   

6.
可持续发展是一种被人们广泛接受的理念,它能够最大限度地维持经济需求与环境保护之间的平衡。这一理念的提出缓解了目前自然资源稀缺,人口快速增长,环境恶劣的现状,并对森林资源管理提出了一个积极的反思,带领人类更好地接受自然给我们带来的各种挑战。本文围绕可持续经营观下森林资源管理应遵循的原则,及可持续经营观下森林资源管理中存在的问题,基于可持续经营观下森林资源管理的几点建议,三个方面展开讨论,对基于可持续经营观下的森林资源管理进行了研究。  相似文献   

7.
海洋生物资源与可持续利用对策研究   总被引:4,自引:0,他引:4  
海洋生态环境恶化和不合理的开发利用,使我国海洋生物资源严重衰退。开展海洋生物资源学相关基础研究,重点进行海洋环境与生物资源保护,运用海洋生物技术等高新技术,科学、合理地开发利用生物资源,是实现海洋生物资源可持续利用和长久发展的可行策略。着重分析了海洋生物资源状况及其生态环境问题,提出了未来我国海洋生物资源的发展对策。  相似文献   

8.
稻飞虱灾变机理及可持续治理的基础研究   总被引:1,自引:0,他引:1  
娄永根  程家安 《昆虫知识》2011,48(2):231-238
稻飞虱(褐飞虱、白背飞虱和褐飞虱)是威胁我国粮食安全最大的生物灾害。本文基于稻飞虱致害能力的高度变异性、对农药的高适应性、传播病毒病和具有远距离迁飞能力等特点,以及研究中存在的稻飞虱迁飞动态、致害性变异和种间互作关系等灾变机理机制不清楚,提出了稻飞虱迁飞时空动态、致害性变异、稻飞虱传播的病毒病、农药对稻飞虱及其天敌的生态毒理效应、稻飞虱基因组数据分析和稻田生态系统对稻飞虱种群数量调控功能6个研究发展方向以阐明稻飞虱灾变的内在机理,为稻飞虱可持续治理体系建设提供理论依据。  相似文献   

9.
农业生态系统的服务功能与可持续利用对策探讨   总被引:29,自引:0,他引:29  
生态系统服务功能是当今生态学的一个热点研究领域。农业生态系统作为一类特殊的人工 -自然复合生态系统 ,它不仅具有高效的、直接的产品生产功能 ,而且还具有环境服务功能、旅游服务功能以及文化教育与美学功能等。因此 ,需要加强农业生态资源与生物多样性的保护 ,加强生态农业与生态农村建设 ,开展农业生态服务价值评估与生态补偿工作 ,同时要大力开发农业的生态旅游功能和文化教育功能  相似文献   

10.
天保工程实施以来东北阔叶红松林的可持续经营   总被引:2,自引:0,他引:2       下载免费PDF全文
20世纪末以来有两个重要的变化影响着东北温带阔叶红松林资源的可持续性,一是天然林资源保护工程(下称天保工程)的实施,另一个是红松不再作为用材树种被采伐。但森林采伐后的更新造林模式并没有显著改变。以长白山腹地-露水河林业局的阔叶红松林为研究对象,利用森林资源清查(二类)和作业设计调查(三类)资料,评估了这两个重要的变化对当前的森林资源的产生影响。结果表明,天保工程的实施调减了采伐量,间接提高了森林的公顷蓄积量,整体上促进了森林资源的恢复。目前,紫椴,蒙古栎,水曲柳和春榆等占商品材总生产量94.7%(蓄积量)。与此同时,可供采伐的这4个树种年生长量却小于采伐量,而林下补植红松,却忽视阔叶树更新的经营模式势必会逐渐增加红松在阔叶红松林中的比例,使目前商品材资源不足的情况更加恶化。总的来说,天保工程促进了公益林区森林资源的可持续性,但降低了用于木材生产的商品林的面积;红松不采伐增加了红松在商品林中的比例,降低了商品林中用材树种比例和商品材的可持续生产能力,从长期看,必然导致可采伐林木资源的枯竭。据此,建议应根据森林培育的目标,选择合适的森林更新恢复模式。  相似文献   

11.
Hunting by Iban forest farmers in West Kalimantan, Indonesia, is an important part of their subsistence economy, and as such became a focus of study as part of a conservation project in the Danau Sentarum Wildlife Reserve. In this paper, we examine Iban hunting of nonhuman primates with comparison to other large mammals. We analyze rates of encounter and capture, comparing encounters, hunting trips, and animal numbers. Information on habitats hunted shows the importance of secondary and old growth forest. Also examined are Iban attitudes, game preferences, and taboos. The significance of these findings is discussed with regard to the threats to wildlife from increases in the use of shotguns, human population, and habitat destruction, showing that conservation may be aided by promoting or enhancing certain aspects of the traditional Iban agroforestry system.  相似文献   

12.
This article describes the hunting tactics and prey selection of the Valley Bisa, a matrilineal, subsistence-oriented society in the Luangwa Valley of Zambia. Although Valley Bisa hunters explain their behavior in their own idioms, many of their tactics, including the stimuli for and timing of hunts, the circular morphology of their hunting patterns, and randomized searches, appear functionally related to the behavior and ecology of their prey. The effects of outlawing traditional harvest techniques and the imposition and enforcement of external constraints on Valley Bisa hunting patterns are discussed. Data on habitats, density of cover, wind direction, species, and initial distance to prey from 50 hunts, in which 16 mammals were killed, are compared and related to success and failure of stalking attempts. Graphs, comparing the numbers of observations for each of four variables with the frequency of stalking attempts, illustrate the cultural style of predation for this group of hunters.This article was initially presented as part of my contribution to a graduate seminar, Public Management of the African Environment, African Studies Program, Indiana University, October 9, 1975. I wish to thank Professor J. Gus Liebenow for extending the invitation to participate in this program.  相似文献   

13.
区域生态系统持续利用管理初探--以青岛市为例   总被引:1,自引:0,他引:1  
运用生态系统管理的相关理念,对青岛市的生态系统进行了分析。在此基础上,构建了结构合理、功能完备的区域生态系统持续利用发展的框架。该构架由4类生态空间组成:①由林木植被及山体等构成的主体生态结构区;②以河流、湖泊、水库等为重点控制区;③城市生态廊道如城市绿色通道、蓝色通道和绿色海岸线等;④以广大农田等为开阔腹地的非控制性组分。最后探讨了区域生态系统持续管理的对策建议:①维护和强化区域整体山水格局的连续性;②保护和恢复区域湿地生态系统;③以循环经济理念推行工业生态化策略;④基于环境友好的空间整合;⑤资源的可持续利用与环境保护工程;⑥实施城市生物多样性保护规划。  相似文献   

14.
15.
甘肃省国际盘羊狩猎场的管理与综合评估   总被引:5,自引:0,他引:5  
甘肃省的肃北、阿克塞、马鬃山同际盘羊狩猎场已开猎运作10年,共狩猎33次,猎获盘羊只,其现状令人关注。本文通过对猎场的多次考究分析,确定了10个反映猎场优劣的因子并赋值,对盘羊猎场进行了综合评估。对3个猎场现状的评估表明,猎场的综合善良好,如果在防范盗猎及管理上加大力度,猎场可望进入优级水平。文中还对猎场的资源和管理进行了研究。  相似文献   

16.
辽西油松纯林可持续经营途径探讨   总被引:9,自引:1,他引:9  
可持续发展自提出以来一直是国际社会在环境与发展领域广泛关注的焦点,已被确立为人类未来新的发展模式,它是指特定区域的需要不危害和削弱其它区域满足其需求能力,同时当代人的需要不对后代人满足其需求能力构成危害的发展[22]。实现可持续发展是全人类的共同心愿,林业可持续发展是整个社会可持续发展的重要组成部分,如何在可持续发展理论的指导下实现林业可持续发展,已成为当今国际社会在林业发展问题上研究的前沿课题和最新趋势。对于如何经营改造辽西大面积的低效益油松纯林,赵荣慧、刘琪王景、郑希伟、李久平、李德民、雷启…  相似文献   

17.
Hunting by Bubi villages around Moka, Bioko, and their impact on the local prey fauna was studied during July–August, 1992. Questionnaires were sent to 45 known hunters in the region in order to find out their techniques and hunting procedures. Hunting trips were also followed (a total of 204 km covered) and counts of animals brought to the villages from 103 recorded trips were also made. There were two main hunting methods employed: trapping and shooting. Most commonly used was snare trapping. At least five different types were used during the study. Guns were less commonly employed. Both techniques are efficient and productive but prey caught by each method differed. Most animals caught by snares were large rodents (Atherurus africanus, Cricetomys emini) and small antelopes (Cephalophus monticola) whereas those shot were usually antelopes (C. monticola and C. ogilbyi), monkeys (Cercopithecus spp.) and, when accompanied by dogs, drills (Mandrillus leucophaeus). The effects of hunting in the region is acute especially since they incur upon the proclaimed protected areas in the south of the island. Hunting trips are gradually being lengthened and areas which were originally unaffected by this activity are now part of the villages' hunting zones.  相似文献   

18.
Abstract

A postal survey of 8639 licensed firearm owners in 1989 indicated that an estimated 117 200 ± 6300 New Zealanders (3.5% of the total population) did some hunting in 1988. An estimated 33 100 former hunters did not hunt in 1988 but thought it likely that they would hunt again in future. The survey provided useful estimates of 1988 national totals for hunting effort (4.4 million hunter days), gross expenditure ($NZ100 million), and harvest (6.5 million animals).

Small-game hunting dominated, involving 81% of hunters, 59% of total hunting effort, and 86% of total numerical harvest: rabbits (Oryctolagus cuniculus) and possums (Trichosurus vulpecula) each comprised 40% of the national bag. Gamebird hunting involved 48% of hunters, 19% of effort, and 11% of total harvest: ducks comprised 73% of the gamebird harvest. Although big-game hunting attracted the fewest hunters (42%) it ranked second for hunting effort (21%). Big game formed 3% of the total numerical harvest: pigs (Sus scrofa), goats (Capra hircus), and red deer (Cervus elaphus scoticus) were the most commonly taken. Big-game were estimated to comprise 49% of total harvest biomass, followed by small-game (47%), and gamebirds (4%). Most deer (nearly 60%) were taken for recreation, with helicopter-based hunting accounting for only one-third the total deer harvest.

A quarter of those people hunting in 1988 hunted on five or fewer days that year, and a relatively small group of mainly professional hunters accounted for a disproportionately large share of the overall harvest Hunters reported spending an average of $851 each on hunting in 1988. Expenditure on big-game comprised 44% of the total, small-game 23%, and gamebirds 33%. Expenditure per animal harvested or per day hunted was greater for big-game animals (other than goats) than for gamebirds, which were more expensive to hunt than small-game. Total hunting effort was inversely related to the average expenditure per animal harvested, regardless of the type of game.  相似文献   

19.
Sensilla on the labial and maxillary palp of Carabus lefebvrei Dejean, 1826 larvae were investigated using scanning and transmission electron microscopy. Two identical sets of sensilla were present on the tips of both palp pairs, and four morphological types of sensilla were identified: sensilla basiconica types 1 and 2, sensilla coeloconica and sensilla digitiformia. Ultrastructure indicates that the sensilla basiconica type 1 and coeloconica have a chemical role as gustatory and olfactory receptors, respectively, while sensilla basiconica type 2 are mechanoreceptors and the sensilla digitiformia are probably thermo‐ and hygroreceptors. Their function is discussed in relation to specialized prey detection and habitat adaptations.  相似文献   

20.
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