Impacts of non-native plants on plant-pollinator interactions.

2020 ◽  
pp. 241-255
Author(s):  
Marcelo A. Aizen ◽  
◽  
Carolina L. Morales ◽  
Keyword(s):  
Invasive Plants ◽  
Native Plants ◽  
Research Field ◽  
Research Approach ◽  
Negative Effects ◽  
Contradictory Evidence ◽  
Pollinator Sharing ◽  
Terrestrial Biodiversity ◽  
Evolutionary Consequences ◽  
Plant Pollinator

There has been growing interest in the consequences of invasive non-native plants for the plant-pollinator mutualism, most likely because of its relevance for the maintenance of terrestrial biodiversity and food production. However, the development of this research field has been thematically uneven and the overall evidence inconclusive. Many studies have focused on how non-native plants interact with native plants via pollinator sharing, which have allowed meta-analytical syntheses, whereas several others have looked at how frequently non-native plants integrate into native plant-pollinator webs and how they affect network structure. However, relatively few studies have addressed the consequences of invasive plants for pollinators. Overall, the research approach in this area has been predominantly phenomenological rather than mechanistic, which has hindered our understanding of apparently contradictory evidence. One key characteristic of invasive non-native plants that seems to mediate negative effects on the pollination mutualism is the high relative abundance that they reach at late stages of invasion. This high dominance is apparently the main trigger of all the disruptive direct and indirect effects that are discussed in this chapter. Finally, we identify several intriguing questions on the ecological and evolutionary consequences of invasive plants for the plant-pollinator mutualism waiting to be answered.

Impacts of non-native plants on plant-pollinator interactions.

2020 ◽  
pp. 241-255
Author(s):  
Marcelo A. Aizen ◽  
Carolina L. Morales
Keyword(s):  
Invasive Plants ◽  
Native Plants ◽  
Research Field ◽  
Research Approach ◽  
Negative Effects ◽  
Contradictory Evidence ◽  
Pollinator Sharing ◽  
Terrestrial Biodiversity ◽  
Evolutionary Consequences ◽  
Plant Pollinator

Abstract There has been growing interest in the consequences of invasive non-native plants for the plant-pollinator mutualism, most likely because of its relevance for the maintenance of terrestrial biodiversity and food production. However, the development of this research field has been thematically uneven and the overall evidence inconclusive. Many studies have focused on how non-native plants interact with native plants via pollinator sharing, which have allowed meta-analytical syntheses, whereas several others have looked at how frequently non-native plants integrate into native plant-pollinator webs and how they affect network structure. However, relatively few studies have addressed the consequences of invasive plants for pollinators. Overall, the research approach in this area has been predominantly phenomenological rather than mechanistic, which has hindered our understanding of apparently contradictory evidence. One key characteristic of invasive non-native plants that seems to mediate negative effects on the pollination mutualism is the high relative abundance that they reach at late stages of invasion. This high dominance is apparently the main trigger of all the disruptive direct and indirect effects that are discussed in this chapter. Finally, we identify several intriguing questions on the ecological and evolutionary consequences of invasive plants for the plant-pollinator mutualism waiting to be answered.

Interactions between invasive plants and heavy metal stresses: a review

2021 ◽  
Author(s):  
Jian Li ◽  
Zhanrui Leng ◽  
Yueming Wu ◽  
Yizhou Du ◽  
Zhicong Dai ◽  
...  
Keyword(s):  
Invasive Species ◽  
Invasive Plants ◽  
Native Plants ◽  
Escape Behavior ◽  
Negative Influence ◽  
Plant Litter ◽  
Global Changes ◽  
Native Plant ◽  
Anthropogenic Contamination ◽  
The Impact

Abstract Global changes have altered the distribution pattern of the plant communities, including invasive species. Anthropogenic contamination may reduce native plant resistance to the invasive species. Thus, the focus of the current review is on the contaminant biogeochemical behavior among native plants, invasive species and the soil within the plant-soil ecosystem to improve our understanding of the interactions between invasive plants and environmental stressors. Our studies together with synthesis of the literature showed that a) the impacts of invasive species on environmental stress were heterogeneous, b) the size of the impact was variable, and c) the influence types were multidirectional even within the same impact type. However, invasive plants showed self-protective mechanisms when exposed to heavy metals (HMs) and provided either positive or negative influence on the bioavailability and toxicity of HMs. On the other hand, HMs may favor plant invasion due to the widespread higher tolerance of invasive plants to HMS together with the “escape behavior” of native plants when exposed to toxic HM pollution. However, there has been no consensus on whether elemental compositions of invasive plants are different from the natives in the polluted regions. A quantitative research comparing plant, litter and soil contaminant contents between native plants and the invaders in a global context is an indispensable research focus in the future.

scholarly journals Football Spectator Violence During Matches at the Zimbabwe Football Association Division One Level in Gweru District

2021 ◽  
Vol 3 (1) ◽  
pp. 19-23
Author(s):  
Nemerai Pedzisai ◽  
◽  
Edmore Nhamo ◽  
Simbarashe Magonde ◽  
◽  
...  
Keyword(s):  
Quantitative Research ◽  
Survey Design ◽  
Simple Random Sampling ◽  
Total Sample ◽  
Research Approach ◽  
Negative Effects ◽  
Football Clubs ◽  
Entry Points ◽  
Midlands Province ◽  
Spectator Violence

Background: A number of football matches in Gweru district have been characterised by undesirable acts of spectator violence resulting in injury and malicious damage to property. Football spectator violence is a very negative phenomenon in football because it chases away sponsors who do not want their organisations and brands to be associated with hooliganism. Violence also discourages spectators from attending football matches as they fear for their safety. This status quo precipitated the need to identify football stakeholders’ perceptions on the causes of spectator violence during football matches at Division One level in Gweru District. Aims: The primary aim and focus of this study was to investigate spectator violence among football spectators in Gweru district in Zimbabwe. Objectives: The objectives of the study were to identify the main causes of football spectator violence and recommend strategies to mitigate or even eliminate this scourge. Study Setting: The study was conducted in Gweru district in the midlands province of Zimbabwe. Materials and Methods: The study adopted the quantitative research approach utilising the descriptive survey design. Closed questionnaires were used to collect data from, twenty division one footballers from four Gweru division one football clubs, twenty spectators, six football referees and four coaches. This resulted in a total sample of fifty (50) respondents. Simple random sampling (Gold Fish Bowl procedure) was used to select the twenty players and six referees. Purposive sampling was used to select the four coaches and twenty football spectators. Statistics: Data was analysed statistically using simple frequency tables. Results and Conclusion: The study revealed that spectator violence during football matches at division one level in Gweru is mainly a result of hooliganism, controversial refereeing, lack of fair play by footballers in the field of play, outcome of matches, rivalry between clubs and euphoria. Factors such as use of juju, prestige seeking by spectators and reporting of violence by the media were found to be minor contributors towards football spectator violence during football matches in Gweru district. Recommendations: The study recommends that the Zimbabwe republic police who provide security during these violent matches should tighten security at football matches by searching all fans thoroughly for dangerous weapons and alcohol at stadia entry points. ZIFA and PSL should educate all football clubs on the negative effects of violence and punish offending teams severely. The clubs should educate their fans to shun violence. Sponsors should include funds in their sponsorship packages for purposes of educating fans on violence. Soccer players should lead by example and avoid provoking other team’s fans

scholarly journals Societal Expectations and Well-being of Academics: Views from University Lecturers in Ghana

2020 ◽  
pp. 74-84
Author(s):  
Dudley W. Ofori ◽  
Jo Bell
Keyword(s):  
Cultural Beliefs ◽  
Well Being ◽  
University Education ◽  
Research Approach ◽  
Negative Effects ◽  
Mind Set ◽  
And Shifts ◽  
Societal Expectations ◽  
University Lecturers

Background: The study aimed to investigate how societal expectation on educational accomplishments can affect workplace well-being of university lecturers. University education is seen by society as the highest level of educational accomplishment in a person’s life and people with such accomplishments are often held in higher esteem by society. In Ghana, this expectation puts pressure on lecturers who are known to have attained higher educational accomplishments. Methods: The study used a qualitative research approach to solicit views from 18 public university lecturers in Ghana. Interpretative Phenomenology Approach (IPA) for data analysis was used to interpret the opinions of lecturers about what society expects of them, how that affects their well-being at work and shifts that are needed to address those expectations. Results: The study found that society indeed expects a lot from university lecturers (core university functions and other cultural and economic issues). Societal expectations have both positive and negative effects on the well-being of lecturers. Findings show that respect that lecturers receive from society provides leverage for positive well-being, while financial pressures placed on them tend to create emotional stresses which impact negatively on their well-being. Conclusion: To our knowledge, this study is the first of its kind to examine the experiences of well-being amongst university academics in Ghana. Results suggest that how the role of university academics is perceived by society can create pressures which affect their well-being negatively. This study highlights the importance of these findings and their impact on well-being. It shows that societal expectations are linked to sociocultural beliefs and economic factors in a developing country context. The authors recommend a mind-set shift amongst society and academics to bring expectations from both sides closer together; through education; engaging community talks on the pressures of societal expectations and demands to create awareness, and observing cultural beliefs that impact the understanding of well-being issues. These initiatives could potentially reduce the pressure of unrealistic expectations on academics and other “knowledge workers”.

scholarly journals Memahami Komunikasi Tumbuhan-Tanah dalam Areal Rhizosfir untuk Optimasi Pengelolaan Lahan

2020 ◽  
Vol 11 (1) ◽  
pp. 33
Author(s):  
Enny Widyati
Keyword(s):  
Invasive Plants ◽  
Root Exudates ◽  
Soil Microbes ◽  
Native Plants ◽  
Chemical Compounds ◽  
Indigenous Plants ◽  
Local Varieties ◽  
Rhizosphere Fungi ◽  
Mycorrhizal Associations ◽  
Mycorrhizal Association

<p><strong>Abstrak.</strong> Seperti halnya dunia manusia, tumbuhan juga mengembangkan sistem komunikasi untuk mencapai kesejahteraan hidupnya. Bahasa yang digunakan adalah senyawa kimia yang diproduksi oleh eksudat akar. Tumbuhan merupakan inisiator karena mereka yang memiliki tujuan untuk apa komunikasi dibangun. Tumbuhan mengeluarkan eksudat akar untuk memanggil atau untuk mengusir mikroba yang diinginkan. Tumbuhan mengirim surat undangan pada beberapa mikroba dengan mensekresikan eksudat akar. Untuk membangun asosiasi mikoriza tumbuhan mengeluarkan gula, asam amino dan strigolakton. Hal tersebut akan dibalas oleh fungi dengan mengeluarkan senyawa flavonoid yang menunjukkan spesifikasi jenis inang-mikoriza. Hadirnya senyawa flavonoid merupakan undangan bagi rhizobium pada tanaman legum untuk membangun asosiasi. Tumbuhan akan menyeleksi rhizobium yang akan diajak berasosiasi dengan mensekresikan senyawa kanavanin yang bersifat toksik. Kesalahan dalam mengeluarkan eksudat akar merupakan surat undangan yang keliru bagi tumbuhan. Dosis senyawa stigolakton yang terlalu rendah tidak akan dapat membentuk asosiasi mikoriza tetapi yang berkembang adalah patogen. Walaupun tumbuhan menghasilkan senyawa fitoantisipin untuk mencegah serangan patogen dan fitoaleksin ketika patogen sudah menginfeksi. Komunikasi akar dengan akar tumbuhan lain dilakukan dengan menghasilkan senyawa alelopati untuk membatasi pertumbuhan akar di sekelilingnya yang dianggap sebagai pesaing. Tanaman invasif atau gulma umumnya selain menghasilkan alelopati juga memproduksi katekin yang dapat membunuh mikroba menguntungkan pada tumbuhan setempat. Akibatnya tumbuhan lokal akan rentan terhadap serangan penyakit dan berujung pada kematian. Selain alelopati, untuk merespon kehadiran tetangganya tumbuhan juga menghasilkan senyawa glukosinolat yang jumlahnya makin meningkat sejalan dengan tingginya biodiversitas vegetasi. Senyawa ini merupakan senyawa beracun bagi patogen, sehingga tumbuhan yang dibudidayakan dengan pola monokultur menjadi rentan terhadap penyakit. Oleh karena itu agar tanah tetap memiliki kandungan senyawa glukosinolat yang memadai serta tetap memelihara kondisi rhizosfir yang dinamis perlu dilakukan pergiliran tanaman varietas lokal setelah beberapa rotasi tanaman.</p><p><em><strong>Abstract.</strong> Similar to human, plants also develop a communication system to achieve their prosperity. Plants utilize chemical compounds of their root exudates as the “languange”. Plants are the initiator of communications, since they define the purposes of building communication. Root exudates are released either to attract or to demenish the soil microbes target as an “invitation letter” to some microbes. To build a mycorrhizal association, for examples, plants issue sugars, amino acids and strygolactones to the rhizosphere. Fungi will reply the invitation by secreting flavonoid compounds that determine host-mycorrhizal specifications. The presence of flavonoids is another invitation to rhizobia to establish association in legume rhizosphere. Plants will select attracted bacteria to build the most host-specific rhizobium association by secreting canavanine compounds that are toxic to non-target rhizobia. Occasionally, an error happened in issuing invitation. When plant release strygolactone in a very low dosages, it will be failure to build mycorrhizal associations otherwise pathogen colonizations, although plants produce either phytoantisipine to prevent pathogens infection or phytoalexin to counter infected pathogens. Communication among roots of neighboring plants is conducted by producing allellopathy compound to limit root growth of the competitors. Invasive plants or weeds generally also produce catechine compounds over the allellophaty that will eliminate soil beneficial microbes of the indigenous plants. As a result, the native plants will be vulnerable to disease and lead to distinct. Responding to the presence of neighboring roots, plants also produce glucosinolate compounds. Glucocynolate consentration will be increased in line with the richness of vegetation biodiversity. These compounds are toxic to the pathogen, which is why plants cultivated in monoculture become more susceptible to disease. Furthermore, to improve soil glucocynolate and to manage the dynamics in the rhizosphere, need to a shift cultivation after several rotations of a commodity with the local varieties.</em></p>

Several Research Topics of Carbon Footprint Order Quantity

2014 ◽  
Vol 1073-1076 ◽  
pp. 2734-2739
Author(s):  
Zhi Yong Tian ◽  
Feng Zheng
Keyword(s):  
Carbon Footprint ◽  
Social Economy ◽  
Influence Factors ◽  
Basic Research ◽  
Research Field ◽  
Research Approach ◽  
Low Carbon ◽  
Order Quantity ◽  
New Research ◽  
Research Assumptions

Research on order quantity plays an important role in logistics and supply chain (SC) whether for traditional economy objective or for low carbon objective. The paper summarizes the research framework of economic order quantity (EOQ) in brief. It also introduces and reviews the new research field carbon footprint order quantity (COQ). Comparing with the research of EOQ, it finds that the research on COQ is just beginning and the research assumptions still remain at the case of the “Square Root” era of EOQ a century ago. Based on some related literatures, the paper analyzes the effect of low carbon on social economy especially some influence factors related to order quantity. And it refers some important market forces affected by low carbon that are ignored by the literatures of COQ currently. Then the paper purposes the basic research approach of COQ. Finally, it provides several important topics of COQ for further research.

Does deal size moderate the effects of board faultlines? Evidence from acquisitions

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Daniel Tidbury ◽  
Steven F. Cahan ◽  
Li Chen
Keyword(s):  
Fixed Effects ◽  
Quantitative Research ◽  
Future Research ◽  
Research Approach ◽  
Strategic Decisions ◽  
Negative Effects ◽  
Content Type ◽  
Instrumental Variable Analysis

Purpose Board faultlines, which reflect intrinsic divisions of board members into relatively homogeneous subgroups, are associated with poor firm performance. This paper aims to extend the existing board faultline research by examining how acquisition deal size moderates the negative implications of board faultlines. Design/methodology/approach This paper uses a sample of acquisitions and a quantitative research approach to conduct statistical analysis. Findings Using a sample of acquisitions announced between 2007 and 2016, this paper finds evidence suggesting that strong faultlines are associated with poorer acquisition outcomes in the long-term, but not in the short term. Further, this paper finds that the effect of faultline strength on long-term acquisition outcomes is weaker for larger acquisition deals than smaller acquisition deals. The findings are consistent with deal size moderating the relation between faultlines and acquisition outcomes. Research limitations/implications This paper addresses possible endogeneity through firm fixed effects and instrumental variable analysis. Although this paper provides evidence on the moderating role of deal size in the context of faultlines, future research could examine the role of additional moderators, such as pro-diversity, trust, board leadership and board and task characteristics. Practical implications The findings suggest that boards need to be aware of situations where the negative effects of faultlines are more likely to come to the fore. For example, faultlines are more likely to play a role in more routine, obscure monitoring than for high-profile strategic decisions. Originality/value The study is multidisciplinary as it draws on the management, organizational behaviour and psychology and finance literature. It contributes to the developing literature on faultlines in several important ways. First, this paper supports their view that faultlines have adverse effects on board performance by showing that faultlines negatively impact discrete strategic investment decisions. Second, this paper provides evidence that deals size moderates the faultline-acquisition performance relation, indicating that the role of faultlines is contextual. Third, this paper finds evidence that suggests investors do not factor in board faultlines when responding to acquisition announcements.

scholarly journals Understanding and evaluating the impact of integrated problem-oriented research programmes: Concepts and considerations

2020 ◽  
Author(s):  
Brian M Belcher ◽  
Karl Hughes
Keyword(s):  
Impact Assessment ◽  
Agricultural Research ◽  
Conservation Status ◽  
Research Impact ◽  
Research Field ◽  
Research Quality ◽  
Research Approach ◽  
Quasi Experimental ◽  
Systems Transformation ◽  
The Impact

Abstract Researchers and research organizations are under increasing pressure to demonstrate that their work contributes to positive change and helps solve pressing societal challenges. There is a simultaneous trend towards more engaged transdisciplinary research that is complexity-aware and appreciates that change happens through systems transformation, not only through technological innovation. Appropriate evaluation approaches are needed to evidence research impact and generate learning for continual improvement. This is challenging in any research field, but especially for research that crosses disciplinary boundaries and intervenes in complex systems. Moreover, evaluation challenges at the project scale are compounded at the programme scale. The Forest, Trees and Agroforestry (FTA) research programme serves as an example of this evolution in research approach and the resulting evaluation challenges. FTA research is responding to the demand for greater impact with more engaged research following multiple pathways. However, research impact assessment in the CGIAR (Consultative Group on International Agricultural Research) was developed in a technology-centric context where counterfactual approaches of causal inference (experimental and quasi-experimental) predominate. Relying solely on such approaches is inappropriate for evaluating research contributions that target policy and institutional change and systems transformation. Instead, we propose a multifaceted, multi-scale, theory-based evaluation approach. This includes nested project- and programme-scale theories of change (ToCs); research quality assessment; theory-based outcome evaluations to empirically test ToCs and assess policy, institutional, and practice influence; experimental and quasi-experimental impact of FTA-informed ‘large n’ innovations; ex ante impact assessment to estimate potential impacts at scale; and logically and plausibly linking programme-level outcomes to secondary data on development and conservation status.

Sign in / Sign up

Export Citation Format

Share Document