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Expansion and Management Implications of Invasive Alien Spartina alterniflora in Yancheng Salt Marshes, China  [PDF]
Chunyue Liu, Hongxing Jiang, Shuqing Zhang, Chunrong Li, Xin Pan, Jun Lu, Yunqiu Hou
Open Journal of Ecology (OJE) , 2016, DOI: 10.4236/oje.2016.63012
Abstract: Improved understanding of the spatial dynamics of invasive plant species is critical for effective land management and control of future invasion. The Yancheng National Nature Reserve (YNNR), an internationally important wetland, has the largest distribution of alien Spartina alterniflora in China. This alien plant was intentionally introduced for erosion prevention and dike protection in China. However, it became an aggressive competitor with native salt marsh plants in the coastal regions in China. High resolution imagery, SPOT-5, was used to map plant communities including invasive species in the south core zone of YNNR with the natural ecosystem of salt marshes in 2003, 2005 and 2008. The fuzzy set assessment method significantly improved the classification accuracies over the conventional error matrix, i.e., from 73.8%, 73.5% and 81.4% to 91.5%, 91.6% and 93.4% in 2003, 2005 and 2008, respectively. It shows a great potential for mapping invasive plant species. Phragmites australis and S. alterniflora were the most accurately mapped classes, and sparse and dense?Suaeda glauca were the least accurately mapped. From 2003 to 2008, S. alterniflora increased 28.8% from 1664.1 to 2142.6 ha in area size, and more than 2.5 times from 742 to 2608 patches. The highest increase in patch number occurred within the interval between 2001 and 3000 m from the eastern baseline. This increase was dominated by small patches with area less than 200 m2. During the study period, the mean spread width was 405 ± 80.7 m in the original large patch of area over 200 ha. The eastward/seaward spread was distinctively larger than the westward/landward. The results enhance the understanding of alien plant’s invasion patterns and help improve conservation efforts.
The evolution of fire and invasive alien plant management practices in fynbos
B.W. van Wilgen
South African Journal of Science , 2010, DOI: 10.4102/sajs.v105i9/10.106
Abstract: The history and development of fire and invasive alien plant management policies in fynbos during the 20th century are reviewed. Fire was initially condemned outright as a destructive force, but as its vital role became better understood, management policies switched from protection to active burning in 1968. During the 1970s, large, coordinated research programmes were established, resulting in a solid basis of knowledge on which to develop fire management policies. Despite policies of prescribed burning, wild fires remain the dominant feature of the region, fortunately driving a variable fire regime that remains broadly aligned with conservation objectives. The problem of conserving fire-adapted fynbos is complicated by invading alien trees that are also fire-adapted. Research results were used to demonstrate the impacts of these invasions on water yields, leading to the creation of one of the largest alien plant control programmes globally. Despite improvements in control methods, alien trees, notably pines, continue to spread almost unchecked. Biological control offered some hope for controlling pines, but was ruled out as too high a risk for these commercially-important trees. Failure to address this problem adequately will almost certainly result in the severe degradation of remaining fynbos ecosystems.
The distribution and introduction pathway of alien invasive species in China

生物多样性 , 2004,
Abstract: Alien invasive species have become a serious environmental issue throughout the world. It is necessary to launch a nationwide investigation on alien invasive species, so as to obtain baseline data, identify causes of invasion, and put forward effective control strategies and measures. Data on classification, origin, pathway and environmental impacts of alien invasive micro-organisms, invertebrates, amphibians and reptiles, fish, birds, mammals, weeds, trees in terrestrial and aquatic ecosystems and alien invasive species in marine ecosystems of China were analyzed, based on literature research, field survey and consultation. 283 alien invasive species have been identified in China, and the number of species of alien invasive micro-organisms, aquatic plants, terrestrial plants, aquatic invertebrates, terrestrial invertebrates, amphibians and reptiles, fish, and mammals were 19, 18, 170, 25, 33, 3, 10, and 5, respectively. The proportion of alien invasive species originating from America, Europe, Asia, Africa and Oceania were 55.1%, 21.7%, 9.9%, 8.1% and 0.6%, respectively. Many institutions and individuals in China lack adequate knowledge of ecological and environmental consequences caused by alien invasive species, with some blindness in the introduction of alien species. For instance, 50.0% of alien invasive plants were intentionally introduced as pasture, feed stock, ornamental plants, textile plants, medicinal plants, vegetables, or lawn plants. 25% of alien invasive animals were intentionally introduced for cultivation, recreation, or biological control. In addition, much effort has been made on introduction of alien species, and little attention has been paid to the management of introduced alien species, which may allow their escape into natural environments and potential threats to the environment. There are also gaps in the quarantine system in China. All invasive micro-organisms were unintentionally introduced, through timber, seedlings, flowerpots, or soil. 76.3% of alien invasive animals invaded through commodity or transportation facilities because of the failure of quarantine. It is recommended that quarantine measures should be strictly implemented. At the same time, the intentional introduction of alien species should be strictly managed and a system of risk assessment should be implemented.
Past approaches and future challenges to the management of fire and invasive alien plants in the new Garden Route National Park
Tineke Kraaij,Richard M. Cowling,Brian W. van Wilgen
South African Journal of Science , 2011, DOI: 10.4102/sajs.v107i9/10.633
Abstract: The recently established Garden Route National Park (GRNP) along the Cape south coast of South Africa occurs in a landscape where indigenous forests, fire-prone fynbos shrublands and fire-sensitive plantations of alien invasive trees are interspersed. We used the area as a case study in the challenges facing conservation managers in the achievement of biodiversity goals in a fire-prone environment. We explored the context within which fire management was practised during the past century by interviewing former catchment managers and reviewing forestry and catchment management policies. Mountain fynbos adjacent to plantations was subjected to burning regimes aimed at the protection of commercial timber resources rather than the preservation of fynbos biodiversity. Prescribed burning of fynbos adjacent to the plantations was typically done in multiple belt systems at rotations of about 4–8 years during spring, summer and autumn, to avoid the winter berg wind season. Such short-rotation and low-intensity fires favour resprouting graminoids over slow-maturing reseeders, and likely account for the compositional impoverishment observed in fynbos near plantations. Current and future challenges faced by the GRNP include (1) balancing conflicting fire management requirements for plantation safety against fynbos conservation; (2) the continual invasion of fynbos by fire-propagated alien pines sourced from plantations; (3) inadequate resources to redress the ‘invasion debt’ caused by the socio-economic legacy and past management neglect; and (4) fragmentation of land use between conservation and forestry threatening the sustainability of the region at large. We provide recommendations for management actions and research priorities to address these challenges.
Preference and Prey Switching in a Generalist Predator Attacking Local and Invasive Alien Pests  [PDF]
Coline C. Jaworski, Ana?s Bompard, Laure Genies, Edwige Amiens-Desneux, Nicolas Desneux
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0082231
Abstract: Invasive pest species may strongly affect biotic interactions in agro-ecosystems. The ability of generalist predators to prey on new invasive pests may result in drastic changes in the population dynamics of local pest species owing to predator-mediated indirect interactions among prey. On a short time scale, the nature and strength of such indirect interactions depend largely on preferences between prey and on predator behavior patterns. Under laboratory conditions we evaluated the prey preference of the generalist predator Macrolophus pygmaeus Rambur (Heteroptera: Miridae) when it encounters simultaneously the local tomato pest Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and the invasive alien pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). We tested various ratios of local vs. alien prey numbers, measuring switching by the predator from one prey to the other, and assessing what conditions (e.g. prey species abundance and prey development stage) may favor such prey switching. The total predation activity of M. pygmaeus was affected by the presence of T. absoluta in the prey complex with an opposite effect when comparing adult and juvenile predators. The predator showed similar preference toward T.?absoluta eggs and B. tabaci nymphs, but T.?absoluta larvae were clearly less attacked. However, prey preference strongly depended on prey relative abundance with a disproportionately high predation on the most abundant prey and disproportionately low predation on the rarest prey. Together with the findings of a recent companion study (Bompard et al. 2013, Population Ecology), the insight obtained on M.?pygmaeus prey switching may be useful for Integrated Pest Management in tomato crops, notably for optimal simultaneous management of B.?tabaci and T.?absoluta, which very frequently co-occur on tomato.
Invasive mechanism and management strategy of Bemisia tabaci (Gennadius) biotype B: Progress report of 973 Program on invasive alien species in China

WAN FangHao,ZHANG GuiFen,LIU ShuSheng,LUO Chen,CHU Dong,ZHANG YouJun,ZANG LianSheng,JIU Min,,ZhiChuang,CUI XuHong,ZHANG LiPing,ZHANG Fan,ZHANG QingWen,LIU WanXue,LIANG Pei,LEI ZhongRen &,ZHANG YongJun,

中国科学C辑(英文版) , 2009,
Abstract: Bemisia tabaci(Gennadius) biotype B,called a "superbug",is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.Th...
Invasive mechanism and management strategy of Bemisia tabaci (Gennadius) biotype B: Progress report of 973 Program on invasive alien species in China
FangHao Wan,GuiFen Zhang,ShuSheng Liu,Chen Luo,Dong Chu,YouJun Zhang,LianSheng Zang,Min Jiu,ZhiChuang Lü,XuHong Cui,LiPing Zhang,Fan Zhang,QingWen Zhang,WanXue Liu,Pei Liang,ZhongRen Lei,YongJun Zhang
Science China Life Sciences , 2009, DOI: 10.1007/s11427-008-0135-4
Abstract: Bemisia tabaci (Gennadius) biotype B, called a “superbug”, is one of the most harmful biotypes of this species complex worldwide. In this report, the invasive mechanism and management of B. tabaci biotype B, based on our 5-year studies, are presented. Six B. tabaci biotypes, B, Q, ZHJ1, ZHJ2, ZHJ3 and FJ1, have been identified in China. Biotype B dominates the other biotypes in many regions of the country. Genetic diversity in biotype B might be induced by host plant, geographical conditions, and/or insecticidal application. The activities of CarE (carboxylesterase) and GSTs (glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants, which might have increased its resistance to insecticides. The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants. Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes. The indigenous B. tabaci biotypes were displaced by the biotype B within 225 d. The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes. B. tabaci biotype B displaced Trialeurodes vaporariorum (Westwood) after 4–7 generations under glasshouse conditions. Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T. vaporariorum. Greater ability of the biotype B to switch to different host plants may enrich its host plants, which might enable it to better compete with T. vaporariorum. Native predatory natural enemies possess greater ability to suppress B. tabaci under field conditions. The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids. The present results provide useful information in explaining the mechanisms of genetic diversity, evolution and molecular eco-adaptation of biotype B. Furthermore, it provides a base for sustainable management of B. tabaci using biological and ecological measures.
Determining a charge for the clearing of invasive alien plant species (IAPs) to augment water supply in South Africa
JN Blignaut, C Marais, JK Turpie
Water SA , 2007,
Abstract: South Africa is running out of water supply options. One option, however, is to control invasive alien plant species (IAPs) within water catchment areas and in riparian zones. The National Water Act and subsequent documentation provide a guide for the use of economic instruments to manage invasive alien plant species at a national, but also at a water management area level. This paper determines the method and level of such an invasive alien plant control charge as part of the water resource management charge.
BIOTROPIA : the Southeast Asian Journal of Tropical Biology , 2005,
Abstract: An inventory of the alien plant species in Indone sia based on the existing references and herbarium specimens concluded that 1936 alien plant species ar e found in Indonesia which belong to 187 families. Field studies should be done to get the complete figur es of alien plant species in Indonesia. Based on the existing figures of the plant species, the invasive alien plant species can be iden tified, followed by studies on the assessment of losses, biology, management and their possible utilizations. Alien plant species are imported to Indonesia for cultivation, collection of the botanical garden, as experimental plants or other curiosities. Aside from plants purposely imported, there are also introduced plant propagules conta-minating imported agricultural products. These alien plant species can be beneficial or have a potential of being invasive. The alien cultivated species consisted of 67% of the total number. More than half of the cultivated plants are ornamental plants. Some of th e species are naturalized or escaped from cultivation and become wild and invasive. Some other natura lized species, adapted well without any problems of invasion. There are 339 species or 17% of the species r ecorded as weeds. The highest record of weeds is found in the family of Poaceae (57 species), follo wed by Asteraceae (53 species) and Cyperaceae (35 species). There are 6 families having more than 10 species of weeds: Amaranthaceae, Asteraceae, Cyperaceae, Euphorbiaceae, Poaceae, and Rubiaceae. Three families have more than 100 species: Asteraceae 162 species, Poaceae 120 species, and Papillionaceae 103 species. Five species of aquatic and 20 species of terrestrial plants considered as important alien plant species in Indonesia were identified and some of their distributions noted
Damage and Management of Alien Species in China  [cached]
Xidong Mu,Yinchang Hu,Hongmei Song,Peixin Wang
Journal of Agricultural Science , 2010, DOI: 10.5539/jas.v2n1p188
Abstract: Alien invasive species have been a seriously environment issue in the whole world. The ecological damages and economic influences of alien invasive species are analyzed in this article, and the government is suggested to strengthen the quarantine services, strictly manage the intentional introduction of alien species, and implement the risk supervision system for the introduction of alien species.
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