New research has found that academics are under pressure to award students higher marks, and that plagiarism is rife in universities.

34 per cent of academics questioned felt that 'dumbing down' reports are correct, while 82 per cent felt that lack of resources is affecting academic standards.

Sir Peter Williams, head of university watchdog the Quality Assurance Agency (QAA), wrote in the Times Higher Education Magazine: “Standards will inevitably change over time, reflecting developments in the world at large.

"Whether they are the same as 10, 20 or 30 years ago is irrelevant.

"What is important is that they should be right for today and meet the diverse needs of society as they are now.

"As higher education embraces more and more of the intellectual range of the population, it may need to redefine and expand the concept of academic standards."

The higher education minister, David Lammy, said: "Our higher education system has a well deserved international reputation for excellence, a fact demonstrated by the numbers of students who are attracted to study here each year from around the world, second only to the USA.

"By 2011 we will have increased funding by 30 per cent in real terms since 1997, spending £11 billion a year on higher education."

The Times study findings came as concerns were raised over the falling quality of published academic research.

The ability to publish articles online has caused a massive increase in the number of areas of academic study from which work can be promoted.

Senior academics have claimed that because the selection of publications is so diverse, even the most unusual articles can be published, leading to a 'dilution' of the pool of quality published research.

Journals such as The Journal of Happiness Studies or Archaeoastronomy and Ethnoastronomy News, are giving an increasing number of academics a platform on which to promote their work.

This has caused problems for the more traditional journals. Alex Bentley, an anthropology lecturer at Durham University, said: "There are many high-quality printed journals that a lot of people aren't interested in anymore because their article will be treated critically and then it won't have any impact.

"What they want is an article that can be treated uncritically and have a big impact."

The problem is allegedly compounded by the way in which the impact of online research is measured, with the number of times an article is cited by others becoming a seal of quality.

Mr Bentley added: "When considering what articles to submit for evaluation, you may have this really good one in a low-ranking journal, and then you have something in a high-ranking journal, and you always submit that high-ranking article to the RAE (Research Assessment Exercise) even if you think that what you wrote was much better in the other one."

This focus on popularity is changing the way that scientists work; a study published in Science by James Evans, a US based sociologist, found that articles which are published online cite more recent work than traditional printed journals.

Although the online publications cite more articles, they come from a narrower selection of journals and articles. Evans concludes that research may become narrower and more isolated in the future as a result of this.

Concerns over online journals and the value of university degrees has also coincided with research published at King’s College London, which argues that the intellectual abilities of Britain’s brightest teenagers have decreased rapidly over the past three decades.

Michael Shayer, professor of applied psychology, ran tests on 800 13-14 year-olds’ ability to think logically and analytically. In one of the tests, 24 per cent of the children from 1976 scored high marks, compared to just 11 per cent of teenagers today.

However, the research found a significant improvement in the performance of the average pupil.

Mr Shayer said: "Teachers are concentrating on giving the basic skills to more pupils, so the average ability goes up, but they fail to stretch the brightest, so the high-end ability falls."

The research has fuelled the debate about the difficulty of A-levels. Results in these exams have risen every year for twenty years.