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A MANET is a form of the wireless network among the mobile, wireless nodes. The presence of various significant attributes in MANET like end to end communications, dynamic topology and simple setup, leads to difficulties like routing, security, and clustering. Network security is an important aspect for both wired and wireless communication. This paper, provide a detail review on different security attacks over the MANETs. Further discussion is carried out by providing of prior solutions to overcome the security attacks and gives a bench mark for future study. An extensive survey of existing researches towards security in MANET is addressed. Later on, a research gap in current state of art in MANET security is discussed. Especially, this survey study mainly focus on security problems, challenges and solution strategies for security concerns in mobile ad-hoc networks.

The effects of growing Jatropha in on-farm and on-station degraded lands were evaluated on carbon (C) sequestration and soil properties. Jatropha accumulated and added to soil significant amounts of C (305 kg ha−1 year−1) from the year one itself. Overall, a 3–5-year old plantation added per year around 4000 kg plant biomass equivalent to 1450 kg C ha−1 – 800 kg C through leaves, 150 kg C through pruned twigs, and 495 kg C as deoiled Jatropha cake. Biodiesel C replacement in the fossil fuel was 230 kg ha−1. Besides adding biomass to the soil, and C replacement in fossil fuel; the standing Jatropha rendered ecosystem service by fixing 5100–6100 kg ha−1 C as the aboveground plus belowground biomass. Carbon additions by Jatropha during 4 years increased C content in the degraded surface soil layer by 19%, resulting in about 2500 kg ha−1 C sequestered. Huge C additions and live root activity under Jatropha increased microbial population, respiration rate and microbial biomass C and N in soil. Along with C additions, 4000 kg ha−1 year−1 plant biomass recycled into the soil 85.5 kg nitrogen, 7.67 kg phosphorus, 43.9 kg potassium, 5.20 kg sulphur, 0.11 kg boron, 0.12 kg zinc and other nutrients. The C additions improved water holding capacity of the soil under Jatropha as compared with the adjacent control soil which increased by 35% at 30 kPa and 21% at 1500 kPa soil water potential.