As I researched, I found that the area was discovered by explorers right around Christmas time. These explorers were amazed to find this beautiful area in the middle of the desert thus naming it Las Vegas, translated as "the meadows" or "fertile plains." The fertility was due to the presence of the artesian springs in what otherwise would have been a desert landscape.
It is my hope this year that each volunteer and each guest experiences what would be equal to discovering a spring in the middle of the hot desert. There is life and joy associated with Christmas and for some pain and sorrow. My prayer is that CFTC can be that place for ALL to experience a refreshing, joyful time together, no matter the context of their life. If you have joy, share it and notice (see) those around you. If you need joy, drink it in, be "seen". We are excited about what this year may hold. Join us either as a volunteer or a guest, but join us nonetheless! Let's have a meaningful Christmas experience together!
Streams in the Desert
The Indian Bend Wash (IBW) flood-control project relies on a greenbelt to carry floods through Scottsdale, Arizona, USA. The greenbelt is characterized by a chain of shallow artificial lakes in a larger floodplain of irrigated turf, which has been protected from encroaching urban development. As such, this urban stream-floodplain complex can be divided into three subsystems: artificial lakes, channelized stream segments, and floodplain. We conducted experiments to evaluate which, if any, of these subsystems were important sites of denitrification, and to explore factors controlling denitrification rates. Denitrification enzyme activity (DEA) bioassays were conducted on sediments from eight lake and six stream segments as well as soil samples from eight floodplain transects. Mass-specific potential denitrification rates were significantly higher in lakes than in streams or floodplains. Nutrient limitation bioassays revealed that nitrate (NO3-) limited denitrification in lake sediments, a surprising finding given that NO3(-)-rich groundwater additions frequently raised lake NO3(-) concentration above 1 mg N/L. Experiments on intact lake cores suggested that denitrification was limited by the rate NO3(-) diffused into sediments, rather than its availability in overlying water. Floodplain denitrification was limited by water content, not NO3(-) or C, and irrigation of soils stimulated denitrification. We constructed a N budget for the IBW stream-floodplain complex based on our experimental results. We found that both lakes and floodplains removed large quantities of N, with denitrification removing 261 and 133 kg N ha(-1) yr(-1) from lake sediments and floodplain soils, respectively, indicating that lakes are hotspots for denitrification. Nevertheless, because floodplain area was >4.5 times that of lakes, floodplain soils removed nearly 2.5 times as much N as lake sediments. Given the desert's low annual precipitation, a finding that floodplain soils are active sites of denitrification might seem implausible; however, irrigation is common in urban landscapes, and it elevated annual denitrification in IBW. Based on our results, we conclude that construction of artificial lakes created hotspots while application of irrigation water created hot moments for denitrification in the stream-floodplain complex, demonstrating that management decisions can improve the ability of urban streams to provide critical ecosystem services like N retention.
This chapter is a prediction of the glory and flourishing estate of the Gospel church, and of the blessings received by it from Christ. Its flourishing state is expressed by the fruitfulness of the desert, being made like to Lebanon, Carmel, and Sharon; and by the inhabitants of it seeing the glory and excellency of Christ, Isa 35:1,2 the ministers of the word are directed and exhorted to strengthen the weak, and comfort the feeble minded, by assuring them of the coming of Christ to save them, Isa 35:3,4 when miracles, both in nature and grace, should be wrought; and great alterations should be made in the wilderness, by the power of God, Isa 35:5-7 when a way should be cast up, described; and the persons that should walk in it are pointed at; and the end it should bring them to, everlasting joy and happiness, Isa 35:8-10.
Water streams in the temporary water beds after heavy showers in the extra-arid Mongolian Trans-Altai Gobi Desert kill many coleopterans especially those with the larvae feeding on and in roots in the soil or in the stem/root base. Another impact of the flooding of desert habitats is the development of fungal infections in the stem- or root-mining larvae and adults. In the areas with often draughts, soil-dwelling larvae of cleonines can remain inactive in the air-dry soil for at least 1.5 years and immediately pupate after rainfall which evidently has a function of the signal for completion of premature development. In the desert landscape with low diversity and population densities of insectivorous birds, reptiles, and mammals, rodents (jerboas) may be the main predators of the root-feeding beetle larvae, digging them out of the soil or taking them off the stem base. 2ff7e9595c
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