nq022811ccf.htm

% of

Net Assets

Total Investment Portfolio (Cost $43,472,191) †

Other Assets and Liabilities, Net

(10,416,254)

Net Assets

DWS Climate Change Fund

			Shares		Value ($)
	Common Stocks 97.0%
Australia 1.8%
Incitec Pivot Ltd. (Cost $494,244)		152,520			686,547
Brazil 0.6%
Sao Martinho SA (Cost $155,266)		17,500			241,601
Canada 5.1%
Canadian Solar, Inc.* (a)		36,300			527,439
Sino-Forest Corp.* (b)		16,000			357,532
Viterra, Inc.		85,160			1,043,079

(Cost $1,473,457)					1,928,050
China 6.8%
Hanwha SolarOne Co., Ltd. (ADR)*		29,600			253,080
JinkoSolar Holding Co., Ltd. (ADR)* (a)		12,450			350,841
LDK Solar Co., Ltd. (ADR)* (a)		23,863			313,082
Renesola Ltd. (ADR)* (a)		16,100			177,905
Suntech Power Holdings Co., Ltd. (ADR)* (a)		29,300			278,350
Tri-Tech Holding, Inc.* (a)		37,900			477,161
Trina Solar Ltd. (ADR)* (a)		14,798			408,425
Yingli Green Energy Holding Co., Ltd. (ADR)* (a)		27,354			315,665

(Cost $2,467,913)					2,574,509
Denmark 1.5%
Vestas Wind Systems AS* (Cost $757,382)		15,967			549,755
France 5.2%
Saft Groupe SA		18,063			691,478
Suez Environnement Co.		30,600			663,014
Veolia Environnement		19,050			627,243

(Cost $1,752,724)					1,981,735
Germany 13.4%
Centrotherm Photovoltaics AG*		17,770			799,411
Elster Group SE (ADR)* (a)		12,650			201,767
K+S AG		7,798			601,930
SGL Carbon SE*		16,895			629,920
Siemens AG (Registered)		5,680			764,801
SMA Solar Technology AG		3,770			400,717
Solarworld AG		46,509			559,187
Wacker Chemie AG		6,195			1,142,719

(Cost $4,292,600)					5,100,452
Hong Kong 1.6%
China Everbright International Ltd. (b)		592,000			280,270
Coslight Technology International Group Ltd.		128,440			74,081
Tianneng Power International Ltd.		576,973			244,249

(Cost $748,681)					598,600
Netherlands 3.5%
CNH Global NV*		17,480			846,906
Koninklijke Boskalis Westminster NV		8,477			440,692
Wavin NV*		4,056			57,697

(Cost $851,469)					1,345,295
Spain 3.6%
Abengoa SA		33,700			945,617
Gamesa Corp. Tecnologica SA*		48,072			423,676

(Cost $1,202,846)					1,369,293
Switzerland 2.9%
ABB Ltd. (Registered)*		19,600			480,268
Bucher Industries AG (Registered)		2,850			618,367

(Cost $771,080)					1,098,635
Taiwan 0.2%
SemiLEDs Corp.* (a) (Cost $90,100)		5,300			82,945
United Kingdom 0.9%
SIG PLC* (Cost $331,123)		160,427			338,124
United States 49.9%
A123 Systems, Inc.* (a)		81,800			775,464
AGCO Corp.*		8,958			490,719
American Superconductor Corp.* (a)		18,933			502,103
Archer-Daniels-Midland Co.		8,250			306,735
Calgon Carbon Corp.*		40,241			564,984
Capstone Turbine Corp.* (a)		235,555			358,044
Clean Energy Fuels Corp.*		51,190			718,708
Comverge, Inc.* (a)		39,346			200,271
Deltic Timber Corp.		11,200			680,624
Energy Recovery, Inc.* (a)		57,790			195,908
EnerNOC, Inc.* (a)		35,050			675,764
EnerSys*		17,050			605,275
First Solar, Inc.* (a)		1,458			214,895
Flow International Corp.*		73,100			291,669
FMC Corp.		3,000			232,320
Franklin Electric Co., Inc.		5,700			242,250
General Electric Co.		48,000			1,004,160
Hain Celestial Group, Inc.*		27,840			830,189
Headwaters, Inc.*		157,250			797,257
Intrepid Potash, Inc.* (a)		20,000			772,000
Johnson Controls, Inc. (a)		26,000			1,060,800
Lindsay Corp. (a)		7,100			501,331
Maxwell Technologies, Inc.* (a)		18,470			334,492
Mueller Water Products, Inc. "A"		192,020			779,601
MYR Group, Inc.*		26,420			596,035
Nalco Holding Co.		7,150			182,826
Pall Corp.		5,650			307,134
Pentair, Inc.		5,690			210,985
Plum Creek Timber Co., Inc. (REIT) (a)		12,438			521,898
Power Integrations, Inc.		13,535			539,234
Power-One, Inc.* (a)		25,200			207,396
Primo Water Corp.* (a)		7,683			98,189
Quanta Services, Inc.*		30,520			696,161
Rockwood Holdings, Inc.*		6,250			290,938
Tetra Tech, Inc.*		16,613			390,405
Titan International, Inc.		13,300			319,466
Veeco Instruments, Inc.* (a)		14,500			689,910
Weyerhaeuser Co. (REIT)		30,755			750,730

(Cost $16,589,457)					18,936,870

Total Common Stocks (Cost $31,978,342)				36,832,411
	Participatory Notes 1.8%
India
Mahindra & Mahindra Ltd. (issuer Merrill Lynch International & Co.), Expiration Date 5/3/2011*		28,570			388,644
McLeod Russel India Ltd. (issuer Merrill Lynch International & Co.), Expiration Date 3/10/2015*		63,200			293,696

Total Participatory Notes (Cost $635,068)				682,340
	Securities Lending Collateral 26.7%
Daily Assets Fund Institutional, 0.23% (c) (d) (Cost $10,152,835)		10,152,835			10,152,835
	Cash Equivalents 1.9%
Central Cash Management Fund, 0.17% (c) (Cost $705,946)		705,946			705,946

For information on the Fund's policies regarding the valuation of investments and other significant accounting policies, please refer to the Fund's most recent semi-annual or annual financial statements.
*	Non-income producing security.
†	The cost for federal income tax purposes was $45,648,775. At February 28, 2011, net unrealized appreciation for all securities based on tax cost was $2,724,757. This consisted of aggregate gross unrealized appreciation for all securities in which there was an excess of value over tax cost of $6,756,591 and aggregate gross unrealized depreciation for all securities in which there was an excess of tax cost over value of $4,031,834.
(a)	All or a portion of these securities were on loan. The value of all securities loaned at February 28, 2011 amounted to $9,684,575 which is 25.5% of net assets.
(b)	Security is listed in country of domicile. Significant business activities of company are in China.
(c)	Affiliated fund managed by Deutsche Investment Management Americas Inc. The rate shown is the annualized seven-day yield at period end.
(d)	Represents collateral held in connection with securities lending. Income earned by the Fund is net of borrower rebates.
ADR: American Depositary Receipt
REIT: Real Estate Investment Trust
As of February 28, 2011, the Fund had the following open forward foreign currency exchange contracts:

Contracts to Deliver

In Exchange For

Settlement

Date

Unrealized

Depreciation ($)

Counterparty

EUR

5,788,292

USD

7,850,000

3/7/2011

(133,295

)

Brown Brothers Harriman & Co.

Currency Abbreviations

EUR	Euro
USD	United States Dollar

At February 28, 2011 the DWS Climate Change Fund had the following sector diversification:

Sector	Market Value ($)		As a % of Common Stocks & Participatory Notes
Industrials		16,010,045		42.7	%
Information Technology		6,855,012		18.3	%
Materials		6,309,677		16.8	%
Consumer Staples		2,887,570		7.7	%
Utilities		1,767,418		4.7	%
Consumer Discretionary		1,693,693		4.5	%
Financials		1,272,628		3.4	%
Energy		718,708		1.9	%
Total		37,514,751		100.0	%

Fair Value Measurements

Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in three broad levels. Level 1 includes quoted prices in active markets for identical securities. Level 2 includes other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, and credit risk). Level 3 includes significant unobservable inputs (including the Fund's own assumptions in determining the fair value of investments). The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

The following is a summary of the inputs used as of February 28, 2011 in valuing the Fund's investments.

	Level 1		Level 2			Level 3		Total
Assets
Common Stocks
Australia	$	—	$	686,547		$	—	$	686,547
Brazil		241,601		—			—		241,601
Canada		1,928,050		—			—		1,928,050
China		2,574,509		—			—		2,574,509
Denmark		—		549,755			—		549,755
France		—		1,981,735			—		1,981,735
Germany		201,767		4,898,685			—		5,100,452
Hong Kong		—		598,600			—		598,600
Netherlands		846,906		498,389			—		1,345,295
Spain		—		1,369,293			—		1,369,293
Switzerland		—		1,098,635			—		1,098,635
Taiwan		82,945		—			—		82,945
United Kingdom		—		338,124			—		338,124
United States		18,936,870		—			—		18,936,870
Participatory Notes		—		682,340			—		682,340
Short-Term Investments(e)		10,858,781		—			—		10,858,781
Total	$	35,671,429	$	12,702,103		$	—	$	48,373,532
Liabilities
Derivatives(f)	$	—	$	(133,295	)	$	—	$	(133,295	)
Total	$	—	$	(133,295	)	$	—	$	(133,295	)

There have been no significant transfers between Level 1 and Level 2 fair value measurements during the period ended February 28, 2011.
(e)	See Investment Portfolio for additional detailed categorizations.
(f)	Derivatives include unrealized appreciation (depreciation) on forward foreign currency exchange contracts.

Derivatives

The following table presents, by major type of derivative contract, the unrealized appreciation (depreciation) of the Fund's derivative instruments as of February 28, 2011 categorized by the primary underlying risk exposure.

Primary Underlying Risk Disclosure		Forward Currency Contracts
Foreign Exchange Contracts		$	(133,295	)

ITEM 2.	CONTROLS AND PROCEDURES

	(a) The Chief Executive and Financial Officers concluded that the Registrant’s Disclosure Controls and Procedures are effective based on the evaluation of the Disclosure Controls and Procedures as of a date within 90 days of the filing date of this report.

	(b) There have been no changes in the registrant’s internal control over financial reporting that occurred during the registrant’s last fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal controls over financial reporting.

ITEM 3.	EXHIBITS

	Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.

Registrant:	DWS Climate Change Fund, a series of DWS Securities Trust

By:	/s/Michael G. Clark Michael G. Clark President

Date:	April 18, 2011

By:	/s/Michael G. Clark Michael G. Clark President

Date:	April 18, 2011



By:	/s/Paul Schubert Paul Schubert Chief Financial Officer and Treasurer

Date:	April 18, 2011