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  <dei:EntityRegistrantName contextRef="Duration_29Nov2011_28Nov2012">BLACKROCK NATURAL RESOURCES TRUST</dei:EntityRegistrantName>
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  <rr:RiskReturnHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">Fund Overview &lt;br/&gt;&lt;br/&gt;&lt;b&gt;Key Facts about BlackRock Natural Resources Trust &lt;/b&gt;</rr:RiskReturnHeading>
  <rr:ObjectiveHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Investment Objective&lt;/b&gt;</rr:ObjectiveHeading>
  <rr:ObjectivePrimaryTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The investment objective of the BlackRock Natural Resources Trust (the &amp;#8220;Fund&amp;#8221;) is to seek long-term growth of capital and to protect the purchasing power of shareholders&amp;#8217; capital by investing in a portfolio of equity securities of domestic and foreign companies with substantial natural resource assets.</rr:ObjectivePrimaryTextBlock>
  <rr:ExpenseHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Fees and Expenses of the Fund&lt;/b&gt;</rr:ExpenseHeading>
  <rr:ExpenseNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the BlackRock-advised fund complex. More information about these and other discounts is available from your financial professional and in the &amp;#8220;Details about the Share Classes&amp;#8221; section on page 17 of the Fund&amp;#8217;s prospectus and in the &amp;#8220;Purchase of Shares&amp;#8221; section on page II-58 of the Fund&amp;#8217;s statement of additional information.</rr:ExpenseNarrativeTextBlock>
  <rr:ExpenseBreakpointDiscounts contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000 in the BlackRock-advised fund complex.</rr:ExpenseBreakpointDiscounts>
  <rr:ExpenseBreakpointMinimumInvestmentRequiredAmount decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_Member" unitRef="USD">25000</rr:ExpenseBreakpointMinimumInvestmentRequiredAmount>
  <rr:ShareholderFeesCaption contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Shareholder Fees&lt;/b&gt;&lt;br/&gt;&lt;b&gt;(fees paid directly from your investment)&lt;/b&gt;</rr:ShareholderFeesCaption>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0525</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice id="Item_2" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice id="Item_3" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.045</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice id="Item_4" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.01</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:MaximumDeferredSalesChargeOverOfferingPrice decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0</rr:MaximumDeferredSalesChargeOverOfferingPrice>
  <rr:OperatingExpensesCaption contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Annual Fund Operating Expenses&lt;br/&gt;(expenses that you pay each year as a percentage of the value of &lt;br/&gt;your investment)&lt;/b&gt;</rr:OperatingExpensesCaption>
  <rr:ManagementFeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.006</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.006</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.006</rr:ManagementFeesOverAssets>
  <rr:ManagementFeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.006</rr:ManagementFeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0025</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.01</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.01</rr:DistributionAndService12b1FeesOverAssets>
  <rr:DistributionAndService12b1FeesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0</rr:DistributionAndService12b1FeesOverAssets>
  <rr:OtherExpensesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.0025</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.0029</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.0029</rr:OtherExpensesOverAssets>
  <rr:OtherExpensesOverAssets decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0027</rr:OtherExpensesOverAssets>
  <rr:AcquiredFundFeesAndExpensesOverAssets id="Item_5" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0001</rr:AcquiredFundFeesAndExpensesOverAssets>
  <rr:AcquiredFundFeesAndExpensesOverAssets id="Item_6" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.0001</rr:AcquiredFundFeesAndExpensesOverAssets>
  <rr:AcquiredFundFeesAndExpensesOverAssets id="Item_7" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.0001</rr:AcquiredFundFeesAndExpensesOverAssets>
  <rr:AcquiredFundFeesAndExpensesOverAssets id="Item_8" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.0001</rr:AcquiredFundFeesAndExpensesOverAssets>
  <rr:ExpensesOverAssets id="Item_9" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0113</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets id="Item_10" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.019</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets id="Item_11" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.019</rr:ExpensesOverAssets>
  <rr:ExpensesOverAssets id="Item_12" decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.0086</rr:ExpensesOverAssets>
  <rr:ExpensesDeferredChargesTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">A contingent deferred sales charge (&amp;#8220;CDSC&amp;#8221;) of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.</rr:ExpensesDeferredChargesTextBlock>
  <rr:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The Total Annual Fund Operating Expenses do not correlate to the ratio of expenses to average net assets given in the Fund&amp;#8217;s most recent annual report, which does not include Acquired Fund Fees and Expenses.</rr:ExpensesNotCorrelatedToRatioDueToAcquiredFundFees>
  <rr:ExpenseExampleHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Example:&lt;/b&gt;</rr:ExpenseExampleHeading>
  <rr:ExpenseExampleNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund&amp;#8217;s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:</rr:ExpenseExampleNarrativeTextBlock>
  <rr:ExpenseExampleYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="USD">634</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">643</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">293</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="USD">88</rr:ExpenseExampleYear01>
  <rr:ExpenseExampleYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="USD">865</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">947</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">597</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="USD">274</rr:ExpenseExampleYear03>
  <rr:ExpenseExampleYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="USD">1115</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">1226</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">1026</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="USD">477</rr:ExpenseExampleYear05>
  <rr:ExpenseExampleYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="USD">1827</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">2022</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">2222</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="USD">1061</rr:ExpenseExampleYear10>
  <rr:ExpenseExampleNoRedemptionByYearCaption contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">You would pay the following expenses if you did not redeem your shares:</rr:ExpenseExampleNoRedemptionByYearCaption>
  <rr:ExpenseExampleNoRedemptionYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">193</rr:ExpenseExampleNoRedemptionYear01>
  <rr:ExpenseExampleNoRedemptionYear01 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">193</rr:ExpenseExampleNoRedemptionYear01>
  <rr:ExpenseExampleNoRedemptionYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">597</rr:ExpenseExampleNoRedemptionYear03>
  <rr:ExpenseExampleNoRedemptionYear03 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">597</rr:ExpenseExampleNoRedemptionYear03>
  <rr:ExpenseExampleNoRedemptionYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">1026</rr:ExpenseExampleNoRedemptionYear05>
  <rr:ExpenseExampleNoRedemptionYear05 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">1026</rr:ExpenseExampleNoRedemptionYear05>
  <rr:ExpenseExampleNoRedemptionYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="USD">2022</rr:ExpenseExampleNoRedemptionYear10>
  <rr:ExpenseExampleNoRedemptionYear10 decimals="INF" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="USD">2222</rr:ExpenseExampleNoRedemptionYear10>
  <rr:PortfolioTurnoverHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Portfolio Turnover&lt;/b&gt;</rr:PortfolioTurnoverHeading>
  <rr:PortfolioTurnoverTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &amp;#8220;turns over&amp;#8221; its portfolio). A higher portfolio turnover may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&amp;#8217;s performance. During the most recent fiscal year, the Fund&amp;#8217;s portfolio turnover rate was 3% of the average value of its portfolio.</rr:PortfolioTurnoverTextBlock>
  <rr:PortfolioTurnoverRate decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_Member" unitRef="pure">0.03</rr:PortfolioTurnoverRate>
  <rr:StrategyHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Principal Investment Strategies of the Fund&lt;/b&gt;</rr:StrategyHeading>
  <rr:StrategyNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The Fund seeks to achieve its objective by investing primarily in equity securities of companies with substantial natural resource assets. Under normal circumstances, the Fund will invest at least 80% of its assets in companies with substantial natural resource assets or in securities the value of which is related to the market value of some natural resource asset. Equity securities include common stock, preferred stock, securities convertible into common stock, rights to subscribe for common stock, and derivative securities or instruments, such as options, the value of which is based on a common stock or group of common stocks. Natural resource assets include materials with economic value that are derived from natural sources, either directly or indirectly, such as precious metals (e.g., gold, silver and platinum), ferrous and nonferrous metals (e.g., iron, aluminum and copper), strategic metals (e.g., uranium and titanium), water, hydrocarbons (e.g., coal, oil and natural gas), timber land, underdeveloped real property and agricultural products (e.g., fertilizers and agricultural chemicals). The Fund normally invests in a portfolio consisting of companies in a variety of natural resource related sectors, such as energy, chemicals, oil, gas, paper, mining, steel or agricultural products. Under certain circumstances, however, the Fund may concentrate its investments in one or more of these sectors or in one or more issuers in the natural resources related industries. The Fund focuses on investments in companies that provide exposure to commodities where existing, and projected, capacity is forecast to approach levels that represent full utilization of that capacity based upon supply and demand forecasts for the commodity. The Fund is a non-diversified fund, which means that it can invest more of its assets in fewer companies than a diversified fund. The Fund will normally invest in both U.S. and non-U.S. companies, including companies located in emerging markets, and in securities denominated in both U.S. dollars and foreign currencies. The Fund may invest in securities of issuers with any market capitalization.</rr:StrategyNarrativeTextBlock>
  <rr:RiskHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Principal Risks of Investing in the Fund&lt;/b&gt;</rr:RiskHeading>
  <rr:RiskNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of principal risks of investing in the Fund.&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Commodities Market Risk&lt;/b&gt; &amp;#8212; Stocks of companies engaged in commodities related industries are especially affected by variations in the commodities markets (that may be due to market events, regulatory developments or other factors that the Fund cannot control) and these companies may lack the resources and the broad business lines to weather hard times.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Emerging Markets Risk&lt;/b&gt; &amp;#8212; Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Equity Securities Risk&lt;/b&gt; &amp;#8212; Stock markets are volatile. The price of equity securities fluctuates based on changes in a company&amp;#8217;s financial condition and overall market and economic conditions.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Foreign Securities Risk&lt;/b&gt; &amp;#8212; Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include:&lt;/li&gt;&lt;/ul&gt;&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight.&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt; &lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 6px"&gt;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;Changes in foreign currency exchange rates can affect the value of the Fund&amp;#8217;s portfolio.&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt; &lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 6px"&gt;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position. &lt;/td&gt;&lt;/tr&gt;&lt;/table&gt; &lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 6px"&gt;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;The governments of certain countries may prohibit or impose substantial restrictions on foreign investments in their capital markets or in certain industries.&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt; &lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 6px"&gt;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws. &lt;/td&gt;&lt;/tr&gt;&lt;/table&gt; &lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 6px"&gt;&lt;/p&gt; &lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt; &lt;tr&gt; &lt;td width="4%"&gt;&lt;/td&gt; &lt;td valign="top" width="3%" align="left"&gt;&amp;#8212;&lt;/td&gt; &lt;td valign="top" align="left"&gt;Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments. &lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Investment Style Risk&lt;/b&gt; &amp;#8212; Under certain market conditions, value investments have performed better during periods of economic recovery. Therefore, this investment style may over time go in and out of favor. At times when the investment style used by the Fund is out of favor, the Fund may underperform other equity funds that use different investment styles.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Market Risk and Selection Risk&lt;/b&gt; &amp;#8212; Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Mid Cap Securities Risk&lt;/b&gt; &amp;#8212; The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Natural Resource Related Assets Risk&lt;/b&gt; &amp;#8212; Because the Fund concentrates its investments in natural resource related assets, the Fund is subject to the risks associated with natural resource investments in addition to the general risk of the stock market. This means the Fund is more vulnerable to the price movements of natural resources and factors that particularly affect the oil, gas, mining, energy, chemicals, paper, steel or agriculture sectors than a more broadly diversified fund. Because the Fund invests primarily in companies with natural resource assets, there is the risk that the Fund will perform poorly during a downturn in natural resource prices.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Non-Diversification Risk&lt;/b&gt; &amp;#8212; The Fund is a non-diversified fund. Because the Fund may invest in securities of a smaller number of issuers, it may be more exposed to the risks associated with and developments affecting an individual issuer than a fund that invests more widely.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Precious Metal Related Securities&lt;/b&gt; &amp;#8212; Prices of precious metals and of precious metal related securities historically have been very volatile. The high volatility of precious metal prices may adversely affect the financial condition of companies involved with precious metals. The production and sale of precious metals by governments or central banks or other larger holders can be affected by various economic, financial, social and political factors, which may be unpredictable and may have a significant impact on the prices of precious metals. Other factors that may affect the prices of precious metals and securities related to them include changes in inflation, the outlook for inflation and changes in industrial and commercial demand for precious metals.&lt;/li&gt;&lt;/ul&gt;&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Sector Risk&lt;/b&gt; &amp;#8212; Sector risk is the risk that the Fund&amp;#8217;s concentration in the securities of companies in a specific market sector or industry will cause the Fund to be more exposed to the price movements of companies in and developments affecting that sector than a more broadly diversified fund. Because the Fund invests primarily in one sector, there is the risk that the Fund will perform poorly during a downturn in that sector.&lt;/li&gt;&lt;/ul&gt;</rr:RiskNarrativeTextBlock>
  <rr:RiskLoseMoney contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments.</rr:RiskLoseMoney>
  <rr:RiskNondiversifiedStatus contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;ul type="square"&gt;&lt;li style="margin-left:-20px"&gt;&lt;b&gt;Non-Diversification Risk&lt;/b&gt; &amp;#8212; The Fund is a non-diversified fund. Because the Fund may invest in securities of a smaller number of issuers, it may be more exposed to the risks associated with and developments affecting an individual issuer than a fund that invests more widely.&lt;/li&gt;&lt;/ul&gt;</rr:RiskNondiversifiedStatus>
  <rr:BarChartAndPerformanceTableHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Performance Information&lt;/b&gt;&lt;/font&gt;</rr:BarChartAndPerformanceTableHeading>
  <rr:PerformanceNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The information shows you how the Fund&amp;#8217;s performance has varied year by year and provides some indication of the risks of investing in the Fund. The table compares the Fund&amp;#8217;s performance to that of the Standard &amp;amp; Poor&amp;#8217;s (S&amp;amp;P) 500&lt;sup style="POSITION: relative; BOTTOM: 0.8ex; VERTICAL-ALIGN: baseline"&gt;&amp;#174;&lt;/sup&gt; Index and the MSCI Natural Resources Index, which are relevant to the Fund because they have characteristics similar to the Fund&amp;#8217;s investment strategies. As with all such investments, past performance (before and after taxes) is not an indication of future results. Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown. However, the table includes all applicable fees and sales charges. If the Fund&amp;#8217;s investment manager and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund&amp;#8217;s returns would have been lower. Updated information on the Fund&amp;#8217;s performance can be obtained by visiting http://www.blackrock.com/funds or can be obtained by phone at 800-882-0052.</rr:PerformanceNarrativeTextBlock>
  <rr:PerformanceInformationIllustratesVariabilityOfReturns contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">The information shows you how the Fund&amp;#8217;s performance has varied year by year and provides some indication of the risks of investing in the Fund.</rr:PerformanceInformationIllustratesVariabilityOfReturns>
  <rr:PerformanceAvailabilityPhone contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">800-882-0052</rr:PerformanceAvailabilityPhone>
  <rr:PerformanceAvailabilityWebSiteAddress contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">http://www.blackrock.com/funds</rr:PerformanceAvailabilityWebSiteAddress>
  <rr:PerformancePastDoesNotIndicateFuture contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">As with all such investments, past performance (before and after taxes) is not an indication of future results.</rr:PerformancePastDoesNotIndicateFuture>
  <rr:BarChartDoesNotReflectSalesLoads contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">Sales charges are not reflected in the bar chart. If they were, returns would be less than those shown.</rr:BarChartDoesNotReflectSalesLoads>
  <rr:PerformanceTableDoesReflectSalesLoads contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">However, the table includes all applicable fees and sales charges.</rr:PerformanceTableDoesReflectSalesLoads>
  <rr:BarChartHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;Investor A Shares ANNUAL TOTAL RETURNS BlackRock Natural Resources Trust As of 12/31 &lt;/b&gt;</rr:BarChartHeading>
  <rr:AnnualReturn2002 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0078</rr:AnnualReturn2002>
  <rr:AnnualReturn2003 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.317</rr:AnnualReturn2003>
  <rr:AnnualReturn2004 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.3068</rr:AnnualReturn2004>
  <rr:AnnualReturn2005 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.5143</rr:AnnualReturn2005>
  <rr:AnnualReturn2006 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.07</rr:AnnualReturn2006>
  <rr:AnnualReturn2007 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.4262</rr:AnnualReturn2007>
  <rr:AnnualReturn2008 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">-0.4774</rr:AnnualReturn2008>
  <rr:AnnualReturn2009 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.5141</rr:AnnualReturn2009>
  <rr:AnnualReturn2010 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.1876</rr:AnnualReturn2010>
  <rr:AnnualReturn2011 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">-0.0953</rr:AnnualReturn2011>
  <rr:BarChartClosingTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">During the ten-year period shown in the bar chart, the highest return for a quarter was 26.54% (quarter ended September 30, 2005) and the lowest return for a quarter was &amp;#8211;34.47% (quarter ended December 31, 2008). The year-to-date return as of September 30, 2012 was 4.07%.</rr:BarChartClosingTextBlock>
  <rr:YearToDateReturnLabel contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">year-to-date return</rr:YearToDateReturnLabel>
  <rr:BarChartYearToDateReturnDate contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">2012-09-30</rr:BarChartYearToDateReturnDate>
  <rr:BarChartYearToDateReturn decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0407</rr:BarChartYearToDateReturn>
  <rr:HighestQuarterlyReturnLabel contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">highest return</rr:HighestQuarterlyReturnLabel>
  <rr:BarChartHighestQuarterlyReturnDate contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">2005-09-30</rr:BarChartHighestQuarterlyReturnDate>
  <rr:BarChartHighestQuarterlyReturn decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.2654</rr:BarChartHighestQuarterlyReturn>
  <rr:LowestQuarterlyReturnLabel contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">lowest return</rr:LowestQuarterlyReturnLabel>
  <rr:BarChartLowestQuarterlyReturnDate contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member">2008-12-31</rr:BarChartLowestQuarterlyReturnDate>
  <rr:BarChartLowestQuarterlyReturn decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">-0.3447</rr:BarChartLowestQuarterlyReturn>
  <rr:PerformanceTableHeading contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;b&gt;As of 12/31/11&lt;br/&gt;Average Annual Total Returns&lt;/b&gt;</rr:PerformanceTableHeading>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">-0.1428</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributions_MemberS000002176_MemberC000005583_Member" unitRef="pure">-0.1437</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributionsAndSales_MemberS000002176_MemberC000005583_Member" unitRef="pure">-0.0928</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">-0.1426</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">-0.1113</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">-0.093</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberStandardAndPoorsFiveHundredIndex_Member" unitRef="pure">0.0211</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear01 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberMsciNaturalResourcesIndex_Member" unitRef="pure">-0.0698</rr:AverageAnnualReturnYear01>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.0282</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributions_MemberS000002176_MemberC000005583_Member" unitRef="pure">0.0261</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributionsAndSales_MemberS000002176_MemberC000005583_Member" unitRef="pure">0.0239</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.0278</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.0311</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.0421</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberStandardAndPoorsFiveHundredIndex_Member" unitRef="pure">-0.0025</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear05 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberMsciNaturalResourcesIndex_Member" unitRef="pure">0.0264</rr:AverageAnnualReturnYear05>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberMsciNaturalResourcesIndex_Member" unitRef="pure">0.104</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberStandardAndPoorsFiveHundredIndex_Member" unitRef="pure">0.0292</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005586_Member" unitRef="pure">0.1334</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005585_Member" unitRef="pure">0.1217</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005584_Member" unitRef="pure">0.1235</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributionsAndSales_MemberS000002176_MemberC000005583_Member" unitRef="pure">0.1118</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012AfterTaxesOnDistributions_MemberS000002176_MemberC000005583_Member" unitRef="pure">0.1222</rr:AverageAnnualReturnYear10>
  <rr:AverageAnnualReturnYear10 decimals="4" contextRef="Duration_29Nov2011_28Nov2012S000002176_MemberC000005583_Member" unitRef="pure">0.1244</rr:AverageAnnualReturnYear10>
  <rr:PerformanceTableNarrativeTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor&amp;#8217;s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C and Institutional Shares will vary.</rr:PerformanceTableNarrativeTextBlock>
  <rr:PerformanceTableUsesHighestFederalRate contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">After-tax returns are calculated using the historical highest individual Federal marginal income tax rates and do not reflect the impact of state and local taxes.</rr:PerformanceTableUsesHighestFederalRate>
  <rr:PerformanceTableNotRelevantToTaxDeferred contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">Actual after-tax returns depend on the investor&amp;#8217;s tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.</rr:PerformanceTableNotRelevantToTaxDeferred>
  <rr:PerformanceTableOneClassOfAfterTaxShown contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">After-tax returns are shown for Investor A Shares only, and the after-tax returns for Investor B, Investor C and Institutional Shares will vary.</rr:PerformanceTableOneClassOfAfterTaxShown>
  <rr:ShareholderFeesTableTextBlock contextRef="Duration_29Nov2011_28Nov2012S000002176_Member">&lt;div style="display:none"&gt;~ http://www.blackrock.com/role/ScheduleShareholderFeesBLACKROCKNATURALRESOURCESTRUST column period compact * ~&lt;/div&gt;

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  <dei:AmendmentFlag contextRef="Duration_29Nov2011_28Nov2012">false</dei:AmendmentFlag>
  <link:footnoteLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">
    <link:loc xlink:type="locator" xlink:href="#Item_2" xlink:label="MaximumDeferredSalesChargeOverOfferingPrice" />
    <link:footnote xlink:type="resource" xlink:label="footnote_MaximumDeferredSalesChargeOverOfferingPrice" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US" id="footnote_MaximumDeferredSalesChargeOverOfferingPrice">A contingent deferred sales charge ("CDSC") of 1.00% is assessed on certain redemptions of Investor A Shares made within 18 months after purchase where no initial sales charge was paid at time of purchase as part of an investment of $1,000,000 or more.</link:footnote>
    <link:footnoteArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote" xlink:from="MaximumDeferredSalesChargeOverOfferingPrice" xlink:to="footnote_MaximumDeferredSalesChargeOverOfferingPrice" />
    <link:loc xlink:type="locator" xlink:href="#Item_3" xlink:label="MaximumDeferredSalesChargeOverOfferingPrice_2" />
    <link:footnote xlink:type="resource" xlink:label="footnote_MaximumDeferredSalesChargeOverOfferingPrice_2" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US" id="footnote_MaximumDeferredSalesChargeOverOfferingPrice_2">The CDSC is 4.50% if shares are redeemed in less than one year. The CDSC for Investor B Shares decreases for redemptions made in subsequent years. After six years there is no CDSC on Investor B Shares. (See the section "Details about the Share Classes - Investor B Shares" in the Fund's prospectus for the complete schedule of CDSCs.)</link:footnote>
    <link:footnoteArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote" xlink:from="MaximumDeferredSalesChargeOverOfferingPrice_2" xlink:to="footnote_MaximumDeferredSalesChargeOverOfferingPrice_2" />
    <link:loc xlink:type="locator" xlink:href="#Item_4" xlink:label="MaximumDeferredSalesChargeOverOfferingPrice_3" />
    <link:footnote xlink:type="resource" xlink:label="footnote_MaximumDeferredSalesChargeOverOfferingPrice_3" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US" id="footnote_MaximumDeferredSalesChargeOverOfferingPrice_3">There is no CDSC on Investor C Shares after one year.</link:footnote>
    <link:footnoteArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote" xlink:from="MaximumDeferredSalesChargeOverOfferingPrice_3" xlink:to="footnote_MaximumDeferredSalesChargeOverOfferingPrice_3" />
    <link:loc xlink:type="locator" xlink:href="#Item_5" xlink:label="AcquiredFundFeesAndExpensesOverAssets" />
    <link:footnote xlink:type="resource" xlink:label="footnote_AcquiredFundFeesAndExpensesOverAssets" xlink:role="http://www.xbrl.org/2003/role/footnote" xml:lang="en-US" id="footnote_AcquiredFundFeesAndExpensesOverAssets">The Total Annual Fund Operating Expenses do not correlate to the ratio of expenses to average net assets given in the Fund's most recent annual report, which does not include Acquired Fund Fees and Expenses.</link:footnote>
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    <link:loc xlink:type="locator" xlink:href="#Item_7" xlink:label="Item_7_lbl" />
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    <link:loc xlink:type="locator" xlink:href="#Item_8" xlink:label="Item_8_lbl" />
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    <link:loc xlink:type="locator" xlink:href="#Item_9" xlink:label="Item_9_lbl" />
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    <link:loc xlink:type="locator" xlink:href="#Item_10" xlink:label="Item_10_lbl" />
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    <link:loc xlink:type="locator" xlink:href="#Item_11" xlink:label="Item_11_lbl" />
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    <link:loc xlink:type="locator" xlink:href="#Item_12" xlink:label="Item_12_lbl" />
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