What are the ways, other than monetary benefits, which can motivate and increase productivity of employees?

Sometimes a pat on the back is all what it needs! This is my experience.
Giving credit and appreciating an employee for their efforts are good steps in motivating them to perform even better.
Give them an equal opportunity to excel in their job / duties and recognize their efforts.
Everyone craves for recognition and appreciation on their work done well.

One of the ways is to assess the ambitious staff, and chieved through the company's general plan Continuous training and capacity building Monetary stimulus

I do not think that monitary gain alone is the driving force of an employee.
There are many other things which act as a catalyst to improve the performance of an employee.
Appreciation and coplements from the superiors will create a positive impact in the performance of the staff.
All people are tended to receive appreciation for their achievements.
The other thing which help the performance of an employee is the continous evanluation and training sessions which will help to improve the quality of work.
Further better communication will contribute to improve the performance of the employees.
Effective communication will maintain a good relationship between management and staff.
Both formal and informal communication have an important role in the smooth running of an organisatiin.
So monitary benefit is only one of the important ingredients which contribute to imrpve the performance.

Trust, possibility to affect to the content of the job, meaningfullness of the job, investing in strengths, healthy working environment.
Money is perhaps the worst way to motivate and increase productivity and very much short term solution.

Money is one of the worst motivators there are.
Monetary incentives (common in sales and finance) are scientifically proven to be detrimental to performance, motivation and ethics.
Herzberg coined the term KITA (Kick in the Ass) which basically means rewarding and punishing based on performance.
A lot of job sectors are based on this principle and it is a very uneffective method.
*Motivation through incentives -Salary -Performance inventives -Stocks -Better job benefits *Motivation through punishment -Threatening to fire the employee -Assigning a worst desk -Exclusion or bullying These things do not change intrinsic motivation; they only get people on the move.
In the end, motivation comes down to fulfilling needs.
There are a couple of useful models that you should look into.
There is a lot of literature on the subject, so I will only point you in the right direction: Alderfer's ERG Theory -Existence Needs -Relatedness Needs -Growth Needs McClelland's Needs theory -Need for Achievement -Need for Affiliation -Need for Power Skinner's Operant Conditioning Model, Herzberg's Motivation-Hygiene Model, Social information processing theory Frustration-Regression Principle: When an employee cannot fulfill his or her higher needs and has a bad relationship with his manager (frustration), it can lead to an excessive focus on lower needs (salary).
Exclusion/Inclusion: This has major psychological implications.
Research has shown that when you exclude employees from the group, the following things happen: Short term: Regain acceptance in the group by working harder Long term: Negative feelings, depression, less commitment and declining performance Exclusion causes the same areas in the brain to light up when you are enduring physical pain.
A lot of problems stem from the lack of access to informal communication networks.
Bottom-up communication gets cluttered with noise.
Negative information is held back through formal communication lines, or the subordinate distorts information due to fear of consequences.
It's important for managers to have good informal relations not just in his/her own echelon, but also in other echelons.
And lastly, there is a nice TED video from Dan Pink.
His Autonomy, Mastery and Purpose hypothesis makes a compelling case on the subject of human motivation: http://www.ted.com/talks/dan_pink_on_motivation.html

Delegation of power and authority at a certain level.

a good relationship between management amd workers. always create a good work enviornment that the employees must enjoy their work and give their best possible. create trust and support in the mind of employees that they must believe that managment is there for support it helps to motivate them and if employees do well productivity must increase.

Motivation and productivity is closely related to the relationship employees have with their managers and the belief that the firm/company/manager will give them opportunity to progress higher in the careers in the company. Also, recoginition is very important for employees to feel valued in ther roles. This will organically promote motivation and increase productivity