What are the rulings of zakat related to financing agriculture and losses incurred therein, determining the nisab, paying zakat on remaining crops and fodder, and the ruling on giving zakat to relatives who are not obligatory to support, knowing that the invested amount was previously subject to zakat?

The preponderant opinion among scholars is that zakat is obligatory only on what is measurable (by volume) and edible as a staple food. One-tenth of the yield is given as zakat if irrigated without effort, and one-half of one-tenth if irrigated with effort. As for agricultural expenses, some scholars hold the view that they are deducted from the produce before its zakat is calculated, especially if the crop contains items not subject to zakat. In such cases, these expenses are considered in exchange for the yield, and what remains is subject to zakat. The loss from the previous season does not affect the zakat of the current season. The crop is subject to zakat if it reaches the nisab on the day of its harvest, regardless of its past zakat status. Your aunt and her children have a greater right to your zakat, but a poor person should not be given more than what suffices for their year's sustenance.