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1.
通过对猕猴桃果实成熟主要指标的测定,确定了秦美适宜采收期为10月3日至12日,西选1号和海沃德为10月下旬。这时果实可溶性固形物含量为6.5─9%,硬度12─16kg/cm2。猕猴桃贮鲜技术在1992/93年度中试(示范)成功的基础上,1993/94年度在64t果实上的应用又取得了好结果。秦美贮藏157天,果实新鲜,完好果和商品果分别为96.6%和97.4%。果实在贮藏期间硬度逐渐降低,由采收时12─16kg/cm2下降到1.6kg/m2;淀粉在酶的作用下不断转化为可溶性糖,可溶性固形物由采收时6.5─9%增加到13.7%。简易降温库成本低,可利用自然低温设施,果实在箱袋内加保鲜剂后置该库内有利于延长猕猴桃贮藏保鲜期。  相似文献   

2.
西藏墨脱格当乡野生虎捕食家畜现状与保护建议   总被引:8,自引:2,他引:6  
曾经在西藏东南的阔叶林中广泛分布的孟加拉虎,目前仅有一个小种群残留在墨脱县境内。2000年5-6月间,在大型家畜遭受野生虎捕食最严重的墨脱县格当乡展开调查,试图寻找减轻虎害的方法。结果表明:1994-1995年虎的捕食率达到最高,对牛和骡马的捕食率分别是17.9%和9.4%;但1996年后,捕食率分别降低到7.8%和1.8%,这可能与1996年当地曾捕杀过一头虎有关。1993-1999年间,全乡牛的数量下降了11%,但骡马数量上升了23%,这是因为当地为增加运输能力而从别处购得骡马。据反映,目前格当乡境内大约有4-5头虎。1997年和1999年,均见母虎和小虎同行,说明该种群尚有繁殖。在抽样的21户居民家中,1999年4月到2000年5月间,66.6%的人家有大型牲畜遭虎捕杀,共损失牛27头,马12匹,而自1993年以来,21户中共有18户(85.8%),有牲畜被杀记录,共计损失117头。其中对牛的捕食率达19.7%,对马达11.9%,平均每户损失牛1.2头,骡马0.5匹。非法狩猎减少了虎的猎物如野猪、羚牛等的数量,是老虎转向家畜的主要原因之一。虎害已对格当乡群众的经济造成较大负面影响。但格当乡以及周边地区保护着中国最后的野生孟加拉虎种群,为确保虎的长期生存同时减少人-虎冲突,建议改变目前放牧方式,尽可能联合放牧、增加看护;改善放牧地条件,清除牧场周围蕨草丛;减少对羚牛等有蹄类的猎杀,以减少对老虎猎物种群的破坏;对部分家畜移入棚内试行圈养,既保护家畜,又提高乳制品产量和增加农家肥料;实行多种经营方法,建议养一些山羊和家禽;政府应该帮助安置好部分愿意外迁的居民,这样既满足这些居民的需要,同时也减轻对当地野生动物种群的压力。  相似文献   

3.
广西龙虎山猕猴种群生态特征   总被引:5,自引:1,他引:4  
王骏  冯敏 《兽类学报》1996,16(4):264-271
1988~1995年,采用定点观察法和绝对计数与相对计数结合法对龙虎山猕猴种群生态作了调查研究。1990年核心区有猕猴14群,500只左右,猴群密度1.6群/km2,种群密度55.6只/km2.猴群大小平均33.8±23.1(n=6)只。一般每隔4~5年分群一次,猴群群体年均增长率14.8%,种群年均增长率为9.7%。猴群中成年猴性比为7.6±6.5(n=12),1~3岁组的性比为0.74±0.61(n=4),群内未成年猴比例为67.7±3.1%(n=12)。发情交配期最早11月12日,最晚次年1月20日,高峰期12月上旬,持续3个月.产仔期最早4月1日,最晚8月14日,高峰期5月上旬,持续时间4个半月.繁殖率45.5%~100%,平均75.4±13.2%(n=21)。新生猴死亡率较低,新生猴性比(雌:雄)平均0.74±0.34(n=5)。  相似文献   

4.
黑莓汁的理化特性及贮藏期营养成分的变化   总被引:11,自引:1,他引:10  
对黑莓浓缩汁的理化特性及其营养成分变化进行研究,结果表明:pH3~4,波长511~514nm时,果汁色泽最佳;果汁抗氧化还原能力很弱,但具有很强的光和热的稳定性。0~4℃低温贮藏1年后,6种维生素的损失率都超过50%;含糖量损失407%;SOD活性和氨基酸含量分别损失10%和124%;含酸量略有增加  相似文献   

5.
洞庭湖稻区黑线姬鼠种群数量预测   总被引:17,自引:0,他引:17  
王勇  陈安国 《兽类学报》1997,17(2):125-130
作者于1986年10月至1995年3月对洞庭湖稻区黑线姬鼠的种群数量作了逐月调查。根据1986年10月至1990年5月在湖南省桃源和汉寿县调查的结果,应用逐步回归分析法建立了预测模型并预报了岳阳县1992年6月、10月,1993年3月、6月、10月,1994年3月、6月、10月和1995年3月黑线姬鼠种群的发生数量,发现数量级预测值与实测值吻合程度良好  相似文献   

6.
利用90年代125万和150万的TM遥感影像及GIS获得的数据,结合该区70、80年代遥感调查数据,分析了科尔沁地区6个县的土地覆盖类型和潜在沙漠化动态及敏感因子.结果表明,1980~1990年该区的沙化面积从53%扩大到70%,林地下降10.7%,草地增加8.38%,主要为低覆盖草地.由于10年来人口密度增加了10人·km-2,耕地平均增加了7%,人口增加和活动是土地覆盖变化的敏感性因子.分析该区沙漠化的自然因素表明气候变化导致沙漠化的正逆过程,人类活动是近代该区沙漠化加剧的直接原因.灰色预测表明该地区2000年以后人口增加,而沙漠化呈增加和减少两种趋势  相似文献   

7.
栗喉蜂虎捕食差异   总被引:1,自引:0,他引:1  
程闯  韩联宪  岩道 《四川动物》2012,31(3):439-442
2010年4~5月和2011年4~6月,用焦点动物取样法对云南省保山市潞江镇怒江河谷栗喉蜂虎捕食差异进行了观察。对栗喉蜂虎雌性成年鸟、雄性成年鸟、青年鸟捕食种类、数量、成功率、食物组成、食物资源量、处理食物成功率及处理时间进行了统计。结果表明,栗喉蜂虎捕食种类包括7类昆虫,以膜翅目Hymenoptera、蜻蜓目Odonate、鳞翅目Lepidoptera昆虫为主;成年雄鸟捕食频次高于成年雌鸟和青年鸟;成年鸟与青年鸟处理食物成功率无显著差异,但二者捕食成功率和处理食物时间差异显著。  相似文献   

8.
板齿鼠种群数量中长期预测的时间序列模型   总被引:11,自引:1,他引:10  
何淼  翁文英 《兽类学报》1996,16(4):297-302
本文利用时间序列方法(三次指数平滑法),并结合季节指数法,建立了板齿鼠种群数量中长期预测(6个月~1年)的时间序列模型,依据1991年11月~1993年12月在广东省博罗县石湾镇里波水管理区对板齿鼠种群数量动态的调查数据,分别预测了1994年和1995年板齿鼠种群数量的发生,预测准确率达到了86.56%。  相似文献   

9.
考氏把盾蚧的生物学特性及防治   总被引:2,自引:0,他引:2  
通过1986-1989年室内外饲养观察,该虫在广州1年发生6代,以雌成虫在被害枝上越冬。1月下旬越冬成虫开始产卵。田间若虫于2月上中旬、4月下旬、8月上旬、10月上旬出现5次高峰。该虫捕食性优势种天敌主要有中华草岭、尼氏钝绥螨。寄生性优势种天敌主要为跳小蜂科的一种小蜂(学名特定),对雌成虫的寄虫生率高达63%~76%。加强观赏植物管理,保护和利用自然天敌,适时施用40%氧乐果、25%喹硫磷、40%  相似文献   

10.
济南市社会经济发展与儿童少年生长的长期变化   总被引:6,自引:2,他引:4  
本文分析了1956-1995年济南市7-18岁儿童少年生长发育的变化趋势。39年间,男女生身高平均增长值分别为10.83cm的9.47cm,平均每10年增长2.768cm和2.43cm;男一体重增长值分别为9.19kg和5.12kg,平均每10年增长2.36kg和1.31kg。将不同年代人均工业总产值作对数转换后发现,与各年龄儿童少年身高、体重的发育水平呈明显的直线正相关,不同年代人均工业总产值的  相似文献   

11.
西藏东南部金珠藏布流域虎的数量和分布现状   总被引:5,自引:1,他引:4  
张明  李寿昌 《兽类学报》1998,18(2):81-86
采用F检验和t检验的方法,对西藏东南部金珠藏布流域野外收集的孟加拉虎足迹数据进行数理统计,统计结果得到虎的6个个体样本,结合在当地的大量访查工作,确证了该流域至少有5只虎的分布。另外嘎隆藏布流域发现1只虎的踪迹。金珠藏布流域虎的活动小区有一定重叠,说明它们可能存在一定的亲缘关系。对金珠藏布流域及邻近地区虎的活动情况也进行了调查,调查结果表明虎的分布和数量自70年代以来呈减少趋势。  相似文献   

12.
Very little is known about prey selection by the Indian tiger Panthera tigris tigris in tropical dry deciduous forests or in wild herbivore-depleted habitats with high livestock pressures. We undertook a short-term study in a large south Indian tiger reserve and examined two intensive study areas (SA's) from October 1998 – June 1999. In each area, herbivore sightings were recorded, scats were collected, and wild prey and livestock kills documented. Chital, wild boar and sambar were the most abundant among the wild herbivores in the study area. Scat analysis revealed wild boar (Sus scrofa) being the most common prey followed by chital (Axis axis) and sambar (Rusa unicolor). Livestock comprised less than 7% of diet intake. Here, the tigers consumed a lower mean prey mass (56.3 kg) than in other reserves. Our study suggests that in tropical dry deciduous forests with low natural prey density, smaller prey species, and high livestock biomass, tigers preferentially kill smaller prey and generally avoid livestock predation.  相似文献   

13.
吉林珲春自然保护区东北虎捕食家畜研究   总被引:1,自引:0,他引:1  
东北虎在中国已经极度濒危,随着位于中俄朝三国边境地区的吉林珲春自然保护区在2001年底的建成,对虎的保护初见成效.然而保护区内虎频繁捕食家畜,引发了当地居民的不满.为了减缓人虎冲突,寻找东北虎捕食家畜的有关规律,作者开展了东北虎捕食家畜的相关研究. 从2001年12月至2007年底,共计有126起,204头家养动物被虎袭击,且呈现逐年上升的趋势.家畜被袭击主要发生在每年的4~9月,没有发现明显的对家畜种的偏好.利用GIS和回归分析表明:1)虎通常不袭击离开村庄小于1 km的家畜;2)人为干扰对家畜的被食用率和虎移动家畜尸体的行为都有显著影响;3)共计有约16 079 kg的家养动物肉被虎食用,造成损失76 084美元;4)对虎袭击地点生态变量的分析表明,东向和南向有更多的家畜被袭击;5)此外,虎多在较低的海拔和坡度、较高的郁闭度,靠近村庄和河流,远离道路等区域捕食家畜.清除套子和防止下套以增加有蹄类的密度对于减少虎捕食家畜非常重要.此外,减少虎袭击地点的人为干扰和改善对家畜的看护也非常关键.  相似文献   

14.
吉林珲春自然保护区野生东北虎捕食家畜的状况   总被引:1,自引:0,他引:1  
2002年5月至2004年10月通过跟踪调查,我们搜集到野生东北虎捕食珲春自然保护区居民家畜的数据,共计38起捕食事件,有51头家畜遭到捕食。这些数据包括捕食事件发现时间、被捕食家畜的数量、类型、年龄、性别、虎痕迹照片和捕食点的GPS数据。运用Mann-WhitneyU检验对数据的差异性进行了检验;结合ArcViewGIS和MapInfo分析,对捕食点的空间属性进行了量化,用多个生态因子对其进行了表征;运用PCA分析了多因子中的主要成分。这些数据表明在珲春,东北虎主要捕食牛和马,对猪和羊没有捕食,对牛和马的捕食也不存在偏好。东北虎倾向捕食成年个体,并且,大多数情况下只捕食1~2个个体。成功的捕食事件中,多为1头遭捕食;该捕食策略为虎权衡后的选择。捕食家畜事件多发生在3~11月的非冰冻期。影响捕食地的生态变量重要性排序为距最近居民区距离>海拔>距最近道路距离>土地利用(Ⅱ型)类型>坡度>坡向>距最近水源距离>植被类型>道路类型>土地利用(I型)类型。距最近居民区距离为3666±2308m,极显著地近于休息卧迹、警戒卧迹和刨痕。该距离更多地集中在4000m以下区域。海拔为280±114m,极显著地低于休息卧迹,显著低于警戒卧迹和刨痕。由于当地居民区多集中在海拔较低的区域,因此,这种显著的不同可以看成是一个伴生的结果。距最近道路距离为522±543m,极显著地近于刨痕,显著近于休息卧迹和警戒卧迹。上述2个人为干扰因子,对捕食的影响具有相似性。对上述3个生态因子的详细研究说明,虎并不愿意有意识地如此接近人类聚居区,而是家畜食物的诱惑,令虎冒险前往。在26个捕食点中,14个在用材林,6个在特护林,3个在农田,2个在灌木林,1个在居民区。被调查的当地居民共损失了11851kg家畜,合人民币116126元。  相似文献   

15.
Innovative conservation tools are greatly needed to reduce livelihood losses and wildlife declines resulting from human–carnivore conflict. Spatial risk modeling is an emerging method for assessing the spatial patterns of predator–prey interactions, with applications for mitigating carnivore attacks on livestock. Large carnivores that ambush prey attack and kill over small areas, requiring models at fine spatial grains to predict livestock depredation hot spots. To detect the best resolution for predicting where carnivores access livestock, we examined the spatial attributes associated with livestock killed by tigers in Kanha Tiger Reserve, India, using risk models generated at 20, 100, and 200‐m spatial grains. We analyzed land‐use, human presence, and vegetation structure variables at 138 kill sites and 439 random sites to identify key landscape attributes where livestock were vulnerable to tigers. Land‐use and human presence variables contributed strongly to predation risk models, with most variables showing high relative importance (≥0.85) at all spatial grains. The risk of a tiger killing livestock increased near dense forests and near the boundary of the park core zone where human presence is restricted. Risk was nonlinearly related to human infrastructure and open vegetation, with the greatest risk occurring 1.2 km from roads, 1.1 km from villages, and 8.0 km from scrubland. Kill sites were characterized by denser, patchier, and more complex vegetation with lower visibility than random sites. Risk maps revealed high‐risk hot spots inside of the core zone boundary and in several patches in the human‐dominated buffer zone. Validation against known kills revealed predictive accuracy for only the 20 m model, the resolution best representing the kill stage of hunting for large carnivores that ambush prey, like the tiger. Results demonstrate that risk models developed at fine spatial grains can offer accurate guidance on landscape attributes livestock should avoid to minimize human–carnivore conflict.  相似文献   

16.
In the Web Valley of the Bale Mountains National Park, the pastoral people suffer from livestock predation by wild carnivores. A total of 704 livestock were reported to be killed by wild carnivores over a 3‐year period, causing a loss of potential revenue of 12 USD per year per household. Reported annual predation rates equated to 1.4% of the livestock population of the study area. Spotted hyaenas were responsible for most livestock predation (57%), followed by leopards (18%), common jackals (16%) and servals (9%). Hyaenas killed all livestock types (horses, donkeys, mules, cattle, goats and sheep) whilst leopards, common jackals and servals killed mostly goats and sheep. A survey of 362 households revealed that the pastoral people keep dogs to protect livestock from carnivores. During 250 nights of observation in the ten settlements, pastoralists were alerted to the presence of hyaenas on 80 occasions by the barking of their dogs. Such tradition of keeping dogs presents a threat to the persistence of the endangered Ethiopian wolf through diseases transmission. Given the frequency of carnivore attacks on livestock, it is desirable to develop alternative livestock protection methods that both minimize livestock losses and reduce the risk of disease transmission to Ethiopian wolves.  相似文献   

17.
In areas bordering wildlife reserves in Zimbabwe, agro-pastoralists suffer livestock depredation by wild carnivores. However, the economic value of these losses, and therefore the levels of compensation required has never been calculated. Between January 1993 and June 1996 in a 33-km2 area of Gokwe communal land bordering the Sengwa Wildlife Research Area, 241 livestock were killed by wild carnivores. Baboons ( Papio ursinus Kerr), lions ( Panthera leo Linnaeus) and leopards ( P. pardus Linnaeus) were the most serious predators, contributing 52%, 34% and 12% of kills, respectively. Baboons only killed young goats ( Capra hircus Linnaeus) and sheep ( Ovis aries Linnaeus) by day, while lions and leopards jumped into fortified kraals at night and killed cattle ( Bos indicus Linnaeus), donkeys ( Equus asinus Linnaeus) and smallstock. In 1995, predators killed 5% of livestock holdings, double that recorded by other African studies. The annual total value of losses depended upon the degree of lion predation on the most valuable species, cattle and donkeys. The average annual loss per livestock-owning household was US$13, or 12% of each household's net annual income. Losses could be reduced by improving kraal defences against lion and leopard predation in the dry season, when attacks were most common.  相似文献   

18.
Abstract: Problem Animal Control Registers, where farmers report livestock losses due to predators as a prerequisite for financial compensation, allow quantifying the human-predator conflict. We analyzed such registers from the Kweneng District of Botswana to assess the impact of native predators on livestock over 3 years. Leopards (Panthera pardus), lions (Panthera leo), wild dogs (Lycaon pictus), brown hyenas (Hyaena brunnea), and cheetahs (Acinonyx jubatus) altogether claimed 2,272 head of livestock. During 2002, the year with the highest impact, the number of animals reported depredated (954) represented 0.34% of the livestock in the district. Leopards and lions caused 64% of the losses. Leopard livestock predation mainly affected calves and was consistent over the district and over time. In contrast, lion predation concentrated on adult cattle, was characterized by local hot spots close to reserve borders, decreased with increasing distance to a reserve, and increased during 2002, an unusually dry year. Interviews with 60 farmers and herders within 30 km of Khutse and Central Kalahari Game Reserves revealed an annual loss of 2.2% of their livestock to predators. Here, small farms (max. 100 domestic animals) suffered relatively higher losses than large, commercial farms, not only due to predation (small farms: 11.7%; large farms: 1.0%) but also from other causes (small: 12.6%; large: 2.8%), even though herders on large farms guarded 5 times more livestock per person than those on small farms. To reduce livestock predation in most of the district where lions are absent, we recommend maternity corrals for pregnant females and calves to better protect vulnerable calves during day and night. In areas close to a reserve where lions roam, herders' incentives to keep all livestock protected in a corral at night have to be enhanced because, according to the registers, only 3 predation cases were reported to have happened inside a corral.  相似文献   

19.
The Sundarban of India and Bangladesh is the only mangrove reserve forest in the world inhabited by the tiger (Panthera tigris). Tigers in the Sundarban mangrove are widely known for frequently straying into the surrounding reclaimed areas. Data collected from household village survey and documents of the Forest Department show that tiger straying incidents happen throughout the year, but most of them occurred during 3 months (Dec–Feb) of the winter season (42%) followed by 3 months (July–Sept) of the monsoon season (31%). 84.22% of cases have been reported from 21 villages of five affected blocks of Sundarban. In most cases, tigers resorted to cattle lifting or poultry feeding. Only in 8.9% of the cases were human beings attacked or killed. Majority of the straying tigers (68.46%) were male. In most cases (78.9%) strayed tigers were aged and 22% of these were partly injured. 96.05% straying occurs during night. This study also aims at exploring the causes of frequent straying, livestock and human casualties as a result of conflict and retaliation killing of tigers. Straying frequency is correlated negatively with the width of the creeks or rivers in the village side and no relationship is identified with the area of the forest block as well as natural prey abundance. Overall, improved nylon fencing, increased patroling, establishment of the Forest Protection Committee (FPC) and the Eco Development Committee (EDC) are not associated with reduction of straying frequency as well as livestock losses to tiger straying.  相似文献   

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