1 . For future humans to survive long periods on Mars, growing food on the planet is a must. It would be too costly and risky to rely upon rocket deliveries to meet the food needs of settlers. With this in mind, scientists are exploring ways to improve space farming.

Researchers work in a controlled greenhouse. They have identified a way that could improve crop production in simulated (模拟的) Martian soil, with different crops grown together. The method is called “intercropping”, invented by ancient Maya farmers in what is now Central America.

In their experiments, the researchers grew cherry tomatoes, peas and carrots together in small, round containers. Tomatoes grown in this way produced about double the amount of tomatoes grown alone—or “monocropped”—in the same simulated Martian soil. The tomatoes were also bigger. They flowered and matured earlier, gave more fruit per plant and had thicker stems. The amounts of peas and carrots did not increase with intercropping.

Rebeca Goncalves, an astrobiologist and lead writer of the study, said the research is the first time the intercropping technique was used in space soil, and that it was a big find—one that they could now build further research on. The crops were grown in simulated Martian regolith, a soil with no organic matter —a near-perfect physical and chemical match to real Martian soil.

The researchers added useful bacteria and nutrients. They also controlled the gases, temperature and humidity inside the greenhouse to match conditions expected in a Martian greenhouse. Intercropping involves growing plants with properties that could help each other grow. The method makes the best use of resources including water and nutrients.

The researchers said the tomato plants in intercropping may have benefited from being close to the pea plants. That is because the peas are good at turning nitrogen from the air, with the help of bacteria introduced into the soil, into an important nutrient. Overall, the tomatoes, peas and carrots grew well, though not as well as in Earth soil in the same greenhouse.

1. What is the benefit of intercropping mentioned in the article?

A．Increasing crop yield.	B．Preventing soil pollution.
C．Decreasing sunlight exposure.	D．Reducing water consumption.

2. What role did the peas play in the process of intercropping?

A．Enhancing growth of carrots.

B．Increasing fruit production in tomatoes.

C．Transforming nitrogen into a crucial nutrient.

D．Improving the variety of bacteria introduced into the soil.

3. What was the key finding of the research?

A．Carrots benefited the most from intercropping.

B．The crops grew as well as they would in Earth soil.

C．The presence of peas helped tomatoes produce more fruit.

D．Peas and carrots showed significant growth improvement in intercropping.

4. What is the main idea of the article?

A．Intercropping is developed for growing crops in space.

B．The study found Intercropping resulted in higher tomato yields.

C．Scientists are struggling to find ways to improve crop production in space.

D．Researchers successfully grew some plants in imitated Martian soil using intercropping.

2 . The rapid pace of global warming and its effects on habitats raise the question of whether species are able to keep up so that they remain in suitable living conditions. Some animals can move fast to adjust to a swiftly changing climate. Plants, being less mobile, rely on means such as seed dispersal(传播) by animals, wind or water to move to new areas, but this redistribution typically occurs within one kilometre of the original plant.

When the climate in a plant’s usual range becomes hotter than it can tolerate, it must find new, cooler areas that might lie many kilometres away. One explanation for long-distance seed dispersal is through transport by migratory (迁徙的) birds. Such birds swallow seeds when eating fruit and can move them tens or hundreds of kilometres outside the range of a plant species.

Gonzáiez-Vary and colleagues report how plants might be able to keep pace with rapid climate change with the help of migratory birds. The authors analysed the fruiting times of plants, patterns of bird migration and the interactions between fruit-eating birds and fleshy-fruited plants across Europe. Plants with fleshy fruits were chosen for this study because most of their seed transport is by migratory birds, and because fleshy-fruited plants are an important part of the woody-plant community in Europe. The common approach until now has been to predict plant dispersal using models fitted to abiotic (非生物的) factors such as the current climate. Gonzáiez-Vary instead analysed an impressive data set of 949 different seed-dispersal interactions between bird and plant communities, together with data on entire fruiting times and migratory patterns of birds across Europe. The researchers also analysed DNA traces from bird wastes to identify the plants and birds responsible for seed dispersal.

1. How do species adapt to climate changes when it’s too hot?

A．All animals will move away across great distanced.

B．Some plants depend on migratory birds to carry seeds.

C．Some plants depend on animals, wind or water to move.

D．Plants’ seeds disperse to cooler places of several kilometres away.

2. Why did researchers mainly study fleshy-fruited plants?

A．Most of these can’t fit rapid climate change

B．Migratory birds like making nests in them

C．Migratory birds transport their seeds.

D．They are favoured by most birds.

3. Why does the author mention “fleshy fruits” and “fruiting times” in paragraph 3?

A．To explain relations between fruit plants and migratory birds.

B．To clarify the reason why birds migrate in fruiting times.

C．To present a fact that migratory bird eats flesh fruits.

D．To show that fruits depend on migratory birds.

4. What is the text mainly about?

A．The advantage of fruit plants.

B．The destination of the bird migration.

C．The adaptation of fruit plants to the climate change.

D．The influence of climate change on plants and animals.

3 . Many people like to plant different plants. Whether sowing seeds (种子) indoors, or directly into your garden, you may want the seeds to germinate (发芽) early.     1    .

A good garden needs good seeds. In order to achieve good germination rates, you need quality seeds. Of course, you can save your own seeds from heritage crops. But if you are buying seeds, you always need to consider the source.    2    . That can make you choose the seeds suitable for growing in your area.

    3    . Once you have your seeds, remember that you will also have to store them correctly. Then you will have to make sure that you provide the seeds with environmental conditions they need to germinate successfully. Increasing germination rates by improving conditions can increase the production.

Seeds require water for germination. Mature seeds take on significant amounts of water before they can begin the germination process. As the seeds take in water, they begin to break down the food stored within the seed. The amount of water required will depend on the type of seed you sow.     4     , germination cannot take place. But watering too much can also cause a range of issues.

Seeds require oxygen for germination. Before seeds develop leaves, they need oxygen from their environment for metabolic (新陈代谢) processes to take place. So it is important to make sure that seeds are buried to the right depth.     5    , you may find it more difficult for oxygen to reach them. Some seeds also need light for germination, so they must be placed on the surface of the soil.

A．If you water too little

B．Just believe in yourself

C．If seeds are buried too deep

D．When too much water is supplied

E．Make sure you choose seeds from an honest supplier

F．Good germination rates depend on environmental conditions

G．These simple tips can help your seeds improve germination rates