The invention claimed is:1. A lighting fixture, comprising:an aluminum housing;at least one light source mechanically supported by the aluminum housing;at least one copper pipe thermally coupled to the aluminum housing to carry a fluid coolant, wherein during operation of the lighting fixture the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture;a plurality of Power over Ethernet (PoE) ports;at least one Universal Serial Bus (USB) port; andat least one integrated sensor assembly coupled to at least one of the plurality of PoE ports or the at least one USB port, the integrated sensor assembly comprising a plurality of sensors including:an air temperature sensor;a visible light sensor;a near infrared (NIR) sensor;a relative humidity sensor;a camera;a carbon dioxide (CO2) sensor; and/oran infrared (IR) sensor,wherein the at least one integrated sensor assembly is coupled to the at least one of the plurality of PoE ports or the at least one USB port of the lighting fixture via at least one extender.2. The lighting fixture of claim 1, wherein the at least one extender includes at least one cable.3. The lighting fixture of claim 1, wherein the at least one extender includes at least one gooseneck flexible extender.4. The lighting fixture of claim 1, wherein the at least one extender includes at least one adjustable-angle extender.5. The lighting fixture of claim 1, wherein the at least one integrated sensor assembly is coupled to the at least one USB port of the lighting fixture via at least one USB extender.6. The lighting fixture of claim 5, wherein the at least one USB extender includes at least one USB cable.7. The lighting fixture of claim 6, wherein the at least one USB extender further includes at least one adjustable-angle extender coupled to the at least one USB cable and the at least one integrated sensor.8. The lighting fixture of claim 5, wherein the at least one USB extender includes at least one flexible USB extender.9. The lighting fixture of claim 5, wherein the at least one USB extender includes at least one adjustable-angle extender.10. The lighting fixture of claim 1, wherein the integrated sensor assembly further comprises at least one of an air pollution sensor, a pH sensor, or a hyperspectral camera.11. The lighting fixture of claim 1, wherein:the at least one integrated sensor assembly includes at least a first integrated sensor assembly coupled to a first port of the at least one of the plurality of PoE ports or the USB port and a second integrated sensor assembly coupled to a second port of the at least one of the plurality of PoE ports or the USB port.12. The lighting fixture of claim 1, wherein:the at least one integrated sensor assembly includes at least a first integrated sensor assembly coupled to a first port of the at least one of the plurality of PoE ports or the USB port and a second integrated sensor assembly coupled to a second port of the at least one of the plurality of PoE ports or the USB port; andat least one of the first integrated sensor assembly and the second integrated sensor assembly is coupled to a corresponding one of the first port and the second port via the at least one extender.13. A lighting fixture, comprising:an aluminum housing;at least one light source mechanically supported by the aluminum housing;at least one copper pipe thermally coupled to the aluminum housing to carry a fluid coolant, wherein during operation of the lighting fixture the fluid coolant flowing through the at least one copper pipe extracts heat generated by the lighting fixture;a plurality of Power over Ethernet (PoE) ports;at least one Universal Serial Bus (USB) port; andat least one integrated sensor assembly coupled to at least one of the plurality of PoE ports or the at least one USB port, the integrated sensor assembly comprising a plurality of sensors including:an air temperature sensor;a visible light sensor;a near infrared (NIR) sensor;a relative humidity sensor;a camera;a carbon dioxide (CO2) sensor; and/oran infrared (IR) sensor,wherein the at least one integrated sensor assembly comprises:a multiple-piece housing comprising:a housing bottom;a housing top coupled to the housing bottom, the housing top including an aperture; anda lens coupled to the housing top to cover the aperture.14. The lighting fixture of claim 13, wherein:the at least one integrated sensor assembly further comprises a single circuit board disposed in the multiple-piece housing;the circuit board has a top side facing the lens and a bottom side facing the housing bottom; andat least two of the plurality of sensors respectively are disposed on the top side and the bottom side of the circuit board.15. The lighting fixture of claim 14, wherein the circuit board comprises:the visible light sensor disposed on the top side of the circuit board;the carbon dioxide (CO2) sensor disposed on the bottom side of the circuit board; andthe infrared (IR) sensor disposed on the bottom side of the circuit board.16. The lighting fixture of claim 14, wherein the at least one integrated sensor assembly is coupled to the lighting fixture via the at least one USB port, and wherein the circuit board further comprises:a sensor USB port;an air flow sensor disposed on a first protruding portion of the circuit board; anda temperature and RH sensor disposed on a second protruding portion of the circuit board.17. The lighting fixture of claim 16, wherein:the housing bottom of the at least one integrated sensor assembly includes a bottom aperture; andthe CO2 sensor is exposed through the bottom aperture of the housing bottom.18. The lighting fixture of claim 16, wherein:the housing bottom of the at least one integrated sensor assembly includes a bottom aperture; andthe IR temperature sensor is exposed through the bottom aperture of the housing bottom.19. The lighting fixture of claim 16, wherein:the housing bottom of the at least one integrated sensor assembly includes a first aperture and a second aperture;the CO2 sensor is exposed through the first aperture of the housing bottom; andthe IR temperature sensor is exposed through the second aperture of the housing bottom.20. The lighting fixture of claim 16, wherein each of the housing bottom and housing top of the at least one integrated sensor assembly comprises:a first protruding portion on a first side of the multiple-piece housing to partially surround the USB port;a second protruding portion on a second side of the multiple-piece housing, opposite the first side of the multiple-piece housing, to contain the air flow sensor; anda third protruding portion on the second side of the multiple-piece housing, adjacent the second protruding portion, to contain the combined temperature and relative humidity sensor.21. The lighting fixture of claim 20, wherein the air flow sensor is disposed on a first protruding portion of the circuit board positioned within the second protruding portion of the multiple-piece housing.22. The lighting fixture of claim 21, wherein the temperature and RH sensor is disposed on a second protruding portion of the circuit board positioned within the third protruding portion of the multiple-piece housing.23. The lighting fixture of claim 20, wherein the temperature and RH sensor is disposed on a protruding portion of the circuit board positioned within the third protruding portion of the multiple-piece housing.24. A system, comprising:A) at least one fluid-cooled LED-based lighting fixture, comprising:an aluminum frame including at least a first channel, a second channel, and at least one enclosed cavity formed therein, the aluminum frame further including a fin protruding from the frame and having a plurality of holes to facilitate mechanical coupling of the lighting fixture to at least one support structure;at least one LED light source mechanically supported by the aluminum frame;a first copper pipe to carry a fluid coolant to extract heat generated by at least the at least one LED light source during operation of the lighting fixture, wherein the first copper pipe is press-fit into the first channel of the aluminum frame so as to establish a first thermal connection between the first copper pipe and the aluminum frame;a second copper pipe to carry the fluid coolant, wherein the second copper pipe is press-fit into the second channel of the aluminum frame so as to establish a second thermal connection between the second copper pipe and the aluminum frame;control circuitry, disposed in the at least one enclosed cavity of the aluminum frame, to receive AC power and to control the at least one LED light source; anda plurality of ports, electrically coupled to at least some of the control circuitry, to provide DC power to at least one auxiliary device coupled to at least one of the plurality of ports;B) at least one fluid coolant circuit mechanically coupled to the first copper pipe and the second copper pipe of the at least one fluid-cooled LED-based lighting fixture;C) a building structure in which the system is disposed, wherein:the at least one fluid-cooled LED-based lighting fixture includes a plurality of lighting fixtures; andthe copper pipes of respective lighting fixtures of the plurality of lighting fixtures are mechanically coupled together by a plurality of push-to-connect fittings so as to form at least a portion of the fluid coolant circuit;D) at least one support structure arranged in the building structure for supporting the plurality of lighting fixtures, wherein respective lighting fixtures are mechanically coupled to the at least one support structure via corresponding fins of the respective lighting fixtures;E) at least one shelving structure to support a plurality of plants, the at least one shelving structure arranged in the building structure with respect to the at least one support structure to facilitate irradiation of the plurality of plants by photosynthetically active radiation (PAR) provided by the plurality of lighting fixtures; andF) at least one integrated sensor assembly coupled to at least a first port of the plurality of ports of the at least one fluid-cooled LED-based lighting fixture in A), the at least one integrated sensor assembly comprising a plurality of sensors to sense a plurality of conditions relating to the plurality of plants supported by the at least one shelving structure in E).25. The system of claim 24, wherein the system does not include an air conditioner comprising an air conditioning condenser, an air conditioning compressor, and/or an air conditioning coil.26. The system of claim 24, wherein the at least one integrated sensor assembly comprises:a multiple-piece housing comprising:a housing bottom;a housing top coupled to the housing bottom, the housing top including an aperture; anda lens coupled to the housing top to cover the aperture.27. The system of claim 24, wherein the plurality of sensors of the at least one integrated assembly comprises:an air temperature sensor;a visible light sensor;a near infrared (NIR) sensor;a relative humidity sensor;a camera;a carbon dioxide (CO2) sensor; and/oran infrared (IR) sensor.28. The system of claim 27, wherein:the at least one integrated sensor assembly comprises a single circuit board;the circuit board has a top side and a bottom side; andat least two of the plurality of sensors respectively are disposed on the top side and the bottom side of the circuit board.29. The system of claim 28, wherein the circuit board comprises:the visible light sensor disposed on the top side of the circuit board;the carbon dioxide (CO2) sensor disposed on the bottom side of the circuit board; andthe infrared (IR) sensor disposed on the bottom side of the circuit board.30. The system of claim 29, wherein the circuit board further comprises:an air flow sensor disposed on a first protruding portion of the circuit board; anda temperature and RH sensor disposed on a second protruding portion of the circuit board.31. The system of claim 27, wherein the integrated sensor assembly further comprises at least one of an air pollution sensor, a pH sensor, or a hyperspectral camera.32. The system of claim 24, wherein:in A), the at least one fluid-cooled LED-based lighting fixture includes:a first fluid-cooled LED-based lighting fixture comprising a first plurality of ports to provide the DC power to at least one first auxiliary device coupled to at least one of the first plurality of ports, the first plurality of ports including the first port in F) and a second port of the first plurality of ports; anda second fluid-cooled LED-based lighting fixture comprising a second plurality of ports to provide the DC power to at least one second auxiliary device coupled to at least one of the second plurality of ports, the second plurality of ports including a first port and a second port of the second plurality of ports;in C), the plurality of lighting fixtures includes the first fluid-cooled LED-based lighting fixture and the second fluid-cooled LED-based lighting fixture;in F), the at least one integrated sensor assembly includes a first integrated sensor assembly coupled to the first port of the first plurality of ports of the first fluid-cooled LED-based lighting fixture, the first integrated sensor assembly comprising a first plurality of sensors to sense a first plurality of conditions relating to the plurality of plants supported by the at least one shelving structure in E); andthe system further comprises:a second integrated sensor assembly, coupled to one of the second port of the first plurality of ports of the first lighting fixture, the first port of the second plurality of ports of the second lighting fixture, or the second port of the second plurality of ports of the second lighting fixture, the second integrated sensor assembly comprising a second plurality of sensors to sense a second plurality of conditions relating to the plurality of plants supported by the at least one shelving structure in E).33. The lighting system of claim 32, wherein at least one of the first integrated sensor assembly and the second integrated sensor assembly is coupled to a corresponding port of one of the first lighting fixture and the second lighting fixture via the at least one extender.34. The lighting system of claim 32, wherein the second integrated sensor assembly is coupled to one of the first port of the second plurality of ports of the second lighting fixture or the second port of the second plurality of ports of the second lighting fixture.35. The lighting system of claim 32, wherein the second integrated sensor assembly is coupled to the second port of the first plurality of ports of the first lighting fixture.36. A method for controlling an agricultural environment, the method comprising:A) flowing a fluid coolant in a coolant circuit, wherein the coolant circuit comprises:at least one LED-based lighting fixture from which the fluid coolant extracts fixture-generated heat as the fluid coolant flows in the coolant circuit through the at least one LED-based lighting fixture, andat least one hydronics loop, coupled to the at least one LED-based lighting fixture, to facilitate temperature regulation in at least a portion of the agricultural environment;B) irradiating a plurality of plants with photosynthetically active radiation (PAR) output by at least one LED-based lighting fixture; andC) sensing a plurality of conditions in the agricultural environment via at least one integrated sensor assembly communicatively coupled to the at least one LED-based lighting fixture, wherein in C), the at least one integrated sensor assembly includes:an air temperature sensor;a visible light sensor;a near infrared (NIR) sensor;a relative humidity sensor;a camera;a carbon dioxide (CO2) sensor; and/oran infrared (IR) sensor, further comprising:D) controlling at least one of 1) the PAR output by the at least one LED lighting fixture and 2) a flow of the fluid coolant in at least one of the at least one LED lighting fixture and the hydronics loop, based at least in part on the plurality of conditions sensed in C) by the at least one integrated sensor assembly.37. The method of claim 36, wherein in C), the at least one integrated sensor assembly is coupled to the at least one LED-based lighting fixture via at least one extender, wherein the at least one extender includes:at least one cable;at least one gooseneck flexible extender; and/orat least one adjustable-angle extender.38. The method of claim 36, wherein the at least one integrated sensor assembly comprises:a multiple-piece housing comprising:a housing bottom;a housing top coupled to the housing bottom, the housing top including an aperture; anda lens coupled to the housing top to cover the aperture,a single circuit board disposed in the multiple-piece housing, the circuit board having a top side facing the lens and a bottom side facing the housing bottom, the circuit board comprising:a visible light sensor disposed on the top side of the circuit board;a carbon dioxide (CO2) sensor disposed on the bottom side of the circuit board;an infrared (IR) temperature sensor disposed on the bottom side of the circuit board;an air flow sensor disposed on a first protruding portion of the circuit board; anda temperature and RH sensor disposed on a second protruding portion of the circuit board.39. The method of claim 36, wherein the at least one LED-based lighting fixture includes a plurality of LED-based lighting fixtures coupled together in a daisy-chain configuration, each LED-based lighting fixture of the plurality of LED-based lighting fixtures comprising the at least one integrated sensor assembly, and wherein A) comprises:flowing the fluid coolant in the coolant circuit through the daisy-chain configuration to extract the fixture-generated heat from respective lighting fixtures of the plurality of LED-based lighting fixtures.40. The method of claim 39, wherein C) comprises:C1) sensing the plurality of conditions in the agricultural environment via the at least one integrated sensor assembly coupled to multiple lighting fixtures of the plurality of LED-based lighting fixtures, wherein for at least a first lighting fixture of the multiple lighting fixtures, the at least one integrated sensor assembly is coupled to the first lighting fixture via at least one extender, wherein the at least one extender includes:at least one cable;at least one gooseneck flexible extender; and/orat least one adjustable-angle extender.41. The method of claim 40, further comprising:D) controlling at least one of 1) the PAR output by at least one lighting fixture of the plurality of LED-based lighting fixtures and 2) a flow of the fluid coolant in at least one of the daisy-chain configuration and the hydronics loop, based at least in part on the plurality of conditions sensed in C) by the at least one integrated sensor assembly.42. An integrated sensor assembly comprising:a multiple-piece housing comprising:a housing bottom;a housing top coupled to the housing bottom, the housing top including an aperture; anda lens coupled to the housing top to cover the aperture,a single circuit board disposed in the multiple-piece housing, the circuit board having a top side facing the lens and a bottom side facing the housing bottom, the circuit board comprising:a visible light sensor disposed on the top side of the circuit board;a carbon dioxide (CO2) sensor disposed on the bottom side of the circuit board;an infrared (IR) temperature sensor disposed on the bottom side of the circuit board;a USB port;an air flow sensor disposed on a first protruding portion of the circuit board; anda temperature and RH sensor disposed on a second protruding portion of the circuit board.43. The integrated sensor assembly of claim 42, wherein:the housing bottom includes a bottom aperture; andthe CO2 sensor is exposed through the bottom aperture of the housing bottom.44. The integrated sensor assembly of claim 42, wherein:the housing bottom includes a bottom aperture; andthe IR temperature sensor is exposed through the bottom aperture of the housing bottom.45. The integrated sensor assembly of claim 42, wherein:the housing bottom includes a first aperture and a second aperture;the CO2 sensor is exposed through the first aperture of the housing bottom; andthe IR temperature sensor is exposed through the second aperture of the housing bottom.46. The integrated sensor assembly of claim 42, wherein each of the housing bottom and housing top comprises:a first protruding portion on a first side of the multiple-piece housing to partially surround the USB port;a second protruding portion on a second side of the multiple-piece housing, opposite the first side of the multiple-piece housing, to contain the air flow sensor; anda third protruding portion on the second side of the multiple-piece housing, adjacent the second protruding portion, to contain the combined temperature and relative humidity sensor.47. The integrated sensor assembly of claim 46, wherein the air flow sensor is disposed on a first protruding portion of the circuit board positioned within the second protruding portion of the multiple-piece housing.48. The integrated sensor assembly of claim 47, wherein the temperature and RH sensor is disposed on a second protruding portion of the circuit board positioned within the third protruding portion of the multiple-piece housing.49. The integrated sensor assembly of claim 46, wherein the temperature and RH sensor is disposed on a protruding portion of the circuit board positioned within the third protruding portion of the multiple-piece housing.50. The integrated sensor assembly of claim 42, wherein the housing is at least one of substantially water tight or substantially air tight.51. The integrated sensor assembly of claim 42, wherein the visible light sensor is spectrally sensitive to at least one of photosynthetically active radiation (PAR) or ultraviolet (UV) radiation.52. The integrated sensor assembly of claim 42, wherein the visible light sensor detects light at a viewing angle of up to 160 degrees.53. The integrated sensor assembly of claim 42, further comprising at least one of an air pollution sensor, a pH sensor, or a hyperspectral camera.54. The integrated sensor assembly of claim 42, wherein the integrated sensor assembly has a length less than about 75 mm, a width less than about 36 mm, and a height less than about 19 mm.55. A controlled environment agriculture (CEA) system comprising the integrated sensor assembly of claim 42.56. An integrated sensor assembly comprising:a multiple-piece housing comprising:a housing bottom having a first aperture and a second aperture;a housing top coupled to the housing bottom, the housing top including a third aperture; anda lens coupled to the housing top to cover the third aperture,wherein each of the housing bottom and housing top comprises:a first protruding portion on a first side of the multiple-piece housing to partially surround a USB port;a second protruding portion on a second side of the multiple-piece housing, opposite the first side of the multiple-piece housing, to contain an air flow sensor; anda third protruding portion on the second side of the multiple-piece housing, adjacent the second protruding portion, to contain a combined temperature and relative humidity (RH) sensor;a single circuit board disposed in the multiple-piece housing, the circuit board having a top side facing the lens and a bottom side facing the housing bottom, the circuit board comprising:a visible light sensor disposed on the top side of the circuit board;a carbon dioxide (CO2) sensor disposed on the bottom side of the circuit board, the CO2 sensor exposed through the first aperture of the housing bottom;an infrared (IR) temperature sensor disposed on the bottom side of the circuit board, the IR temperature sensor exposed through the second aperture of the housing bottom;the USB port;the air flow sensor disposed on a first protruding portion of the circuit board positioned within the second protruding portion of the multiple-piece housing; andthe temperature and RH sensor disposed on a second protruding portion of the circuit board positioned within the third protruding portion of the multiple-piece housing.