The FTSE 100 opened in positive territory on Monday morning, albeit only slightly, as markets made a tentative start to the new week following the dramatic sell-off seen over recent sessions.London's benchmark index closed Friday's session at just 6,116 following a number of steep declines since the Federal Reserve last week confirmed its intention to taper its stimulus programme if economic data continues to improve. Since hitting a 13-year high on May 22nd, the Footsie has now dropped nearly 11%."There is no doubt that the markets are still in the process of pricing in the Federal Reserve's plan to tone down its stimulus drive later this year," said Financial Sales Trader Max Cohen from Spreadex this morning.He said that after recent steep falls, "investors will be hesitant to enter at current levels consider the volatility".Limiting gains this morning will be the news that Goldman Sachs has joined a growing list of brokers to cut its growth forecast for China for this year and the next. The investment bank now expects China to grow by only 7.4% in 2013 compared to the previous 7.8% estimate. For 2014, Goldman now anticipates a 7.7% expansion compared to the prior 8.4% forecast."The liquidity tightening is another indication that the new government has put priorities on tackling the structural problems," Goldman said. "These policies help to foster more sustainable medium-term growth, but will test the government's tolerance for a cyclical downturn," the broker said.Miners hit by China concerns; ENRC drops on offer from foundersMining stocks were under pressure this morning on concerns over slowing growth in China and the effect this will have on the demand for commodities. ENRC, Antofagasta, Vedanta, Glencore Xstrata, Rio Tinto and Anglo American were among the worst performers early on.ENRC was one of the worst hit after its founding shareholders and the Kazakhstan government launched a 234.3p-a-share (£3.03bn) offer for the miner. 26%-owner Kazakhmys - which would only receive $0.89bn for its stake in ENRC - dropped sharply this morning after saying that while the offer undervalues ENRC, it is the best option for shareholders given that the risks of further erosion of its stake are "considerable".Rio Tinto meanwhile underwhelmed this morning with the decision to keep hold of its diamonds business, saying that market fundamentals remain robust with growing demand for luxury goods in Asia and continued strong demand in the US. Vodafone was in demand after confirming its intention to acquire Kabel Deutschland, Germany's biggest cable company, for more than £8.5bn. Supermarket peers Sainsbury and Morrison were under the weather today after Citigroup downgraded its ratings on the stocks to 'sell' and 'neutral', respectively. Tesco, immune from a downgrade given that the broker already rates it as a 'sell', edged higher.FTSE 100 - RisersG4S (GFS) 235.40p +1.47%Severn Trent (SVT) 1,637.00p +1.43%Tullow Oil (TLW) 1,037.00p +1.37%Vodafone Group (VOD) 177.85p +1.14%Experian (EXPN) 1,116.00p +1.09%Wood Group (John) (WG.) 791.00p +1.09%United Utilities Group (UU.) 656.00p +1.08%Royal Bank of Scotland Group (RBS) 284.70p +1.06%Serco Group (SRP) 591.50p +0.94%GKN (GKN) 292.50p +0.86%FTSE 100 - FallersVedanta Resources (VED) 1,058.00p -3.56%Eurasian Natural Resources Corp. (ENRC) 213.00p -1.80%Antofagasta (ANTO) 823.50p -1.79%Rolls-Royce Holdings (RR.) 1,138.00p -1.47%Anglo American (AAL) 1,336.00p -1.18%Glencore Xstrata (GLEN) 283.75p -1.12%Fresnillo (FRES) 901.00p -1.10%Rio Tinto (RIO) 2,646.50p -1.03%International Consolidated Airlines Group SA (CDI) (IAG) 258.10p -1.00%Diageo (DGE) 1,825.50p -0.98%FTSE 250 - RisersKenmare Resources (KMR) 25.69p +5.72%Interserve (IRV) 497.80p +2.83%Alent (ALNT) 340.00p +2.50%Afren (AFR) 122.90p +2.50%Computacenter (CCC) 419.20p +2.49%Essar Energy (ESSR) 121.90p +2.44%Drax Group (DRX) 546.50p +1.67%Pennon Group (PNN) 639.50p +1.19%Halfords Group (HFD) 306.00p +1.19%Balfour Beatty (BBY) 223.60p +1.18%FTSE 250 - FallersKazakhmys (KAZ) 244.40p -9.28%Centamin (DI) (CEY) 33.80p -5.08%Perform Group (PER) 560.00p -4.60%Fidelity China Special Situations (FCSS) 81.70p -4.44%Barr (A.G.) (BAG) 515.50p -3.73%Countrywide (CWD) 495.50p -2.84%Sports Direct International (SPD) 523.00p -2.70%Dixons Retail (DXNS) 41.67p -2.69%African Barrick Gold (ABG) 118.00p -2.64%Imagination Technologies Group (IMG) 302.80p -2.42%